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mbedtls/library/ssl_tls.c
Manuel Pégourié-Gonnard c40b685837 Fix bug in record decompression 
ssl_decompress_buf() was operating on data from the ssl context, but called at
a point where this data is actually in the rec structure. Call it later so
that the data is back to the ssl structure.
2020-01-24 10:44:13 +01:00

12976 lines
418 KiB
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/*
* SSLv3/TLSv1 shared functions
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
* The SSL 3.0 specification was drafted by Netscape in 1996,
* and became an IETF standard in 1999.
*
* http://wp.netscape.com/eng/ssl3/
* http://www.ietf.org/rfc/rfc2246.txt
* http://www.ietf.org/rfc/rfc4346.txt
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_SSL_TLS_C)
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
#include "mbedtls/ssl.h"
#include "mbedtls/ssl_internal.h"
#include "mbedtls/debug.h"
#include "mbedtls/error.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/version.h"
#include <string.h>
#if defined(MBEDTLS_USE_PSA_CRYPTO)
#include "mbedtls/psa_util.h"
#include "psa/crypto.h"
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#include "mbedtls/oid.h"
#endif
static void ssl_reset_in_out_pointers( mbedtls_ssl_context *ssl );
static uint32_t ssl_get_hs_total_len( mbedtls_ssl_context const *ssl );
/* Length of the "epoch" field in the record header */
static inline size_t ssl_ep_len( const mbedtls_ssl_context *ssl )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
return( 2 );
#else
((void) ssl);
#endif
return( 0 );
}
/*
* Start a timer.
* Passing millisecs = 0 cancels a running timer.
*/
static void ssl_set_timer( mbedtls_ssl_context *ssl, uint32_t millisecs )
{
if( ssl->f_set_timer == NULL )
return;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "set_timer to %d ms", (int) millisecs ) );
ssl->f_set_timer( ssl->p_timer, millisecs / 4, millisecs );
}
/*
* Return -1 is timer is expired, 0 if it isn't.
*/
static int ssl_check_timer( mbedtls_ssl_context *ssl )
{
if( ssl->f_get_timer == NULL )
return( 0 );
if( ssl->f_get_timer( ssl->p_timer ) == 2 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "timer expired" ) );
return( -1 );
}
return( 0 );
}
static void ssl_update_out_pointers( mbedtls_ssl_context *ssl,
mbedtls_ssl_transform *transform );
static void ssl_update_in_pointers( mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
static int ssl_parse_record_header( mbedtls_ssl_context const *ssl,
unsigned char *buf,
size_t len,
mbedtls_record *rec );
int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char *buf,
size_t buflen )
{
int ret = 0;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "=> mbedtls_ssl_check_record" ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "record buffer", buf, buflen );
/* We don't support record checking in TLS because
* (a) there doesn't seem to be a usecase for it, and
* (b) In SSLv3 and TLS 1.0, CBC record decryption has state
* and we'd need to backup the transform here.
*/
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_STREAM )
{
ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
goto exit;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
else
{
mbedtls_record rec;
ret = ssl_parse_record_header( ssl, buf, buflen, &rec );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 3, "ssl_parse_record_header", ret );
goto exit;
}
if( ssl->transform_in != NULL )
{
ret = mbedtls_ssl_decrypt_buf( ssl, ssl->transform_in, &rec );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 3, "mbedtls_ssl_decrypt_buf", ret );
goto exit;
}
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
exit:
/* On success, we have decrypted the buffer in-place, so make
* sure we don't leak any plaintext data. */
mbedtls_platform_zeroize( buf, buflen );
/* For the purpose of this API, treat messages with unexpected CID
* as well as such from future epochs as unexpected. */
if( ret == MBEDTLS_ERR_SSL_UNEXPECTED_CID ||
ret == MBEDTLS_ERR_SSL_EARLY_MESSAGE )
{
ret = MBEDTLS_ERR_SSL_UNEXPECTED_RECORD;
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "<= mbedtls_ssl_check_record" ) );
return( ret );
}
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
#define SSL_DONT_FORCE_FLUSH 0
#define SSL_FORCE_FLUSH 1
#if defined(MBEDTLS_SSL_PROTO_DTLS)
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* Top-level Connection ID API */
int mbedtls_ssl_conf_cid( mbedtls_ssl_config *conf,
size_t len,
int ignore_other_cid )
{
if( len > MBEDTLS_SSL_CID_IN_LEN_MAX )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( ignore_other_cid != MBEDTLS_SSL_UNEXPECTED_CID_FAIL &&
ignore_other_cid != MBEDTLS_SSL_UNEXPECTED_CID_IGNORE )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
conf->ignore_unexpected_cid = ignore_other_cid;
conf->cid_len = len;
return( 0 );
}
int mbedtls_ssl_set_cid( mbedtls_ssl_context *ssl,
int enable,
unsigned char const *own_cid,
size_t own_cid_len )
{
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->negotiate_cid = enable;
if( enable == MBEDTLS_SSL_CID_DISABLED )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Disable use of CID extension." ) );
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Enable use of CID extension." ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "Own CID", own_cid, own_cid_len );
if( own_cid_len != ssl->conf->cid_len )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "CID length %u does not match CID length %u in config",
(unsigned) own_cid_len,
(unsigned) ssl->conf->cid_len ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
memcpy( ssl->own_cid, own_cid, own_cid_len );
/* Truncation is not an issue here because
* MBEDTLS_SSL_CID_IN_LEN_MAX at most 255. */
ssl->own_cid_len = (uint8_t) own_cid_len;
return( 0 );
}
int mbedtls_ssl_get_peer_cid( mbedtls_ssl_context *ssl,
int *enabled,
unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ],
size_t *peer_cid_len )
{
*enabled = MBEDTLS_SSL_CID_DISABLED;
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ||
ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* We report MBEDTLS_SSL_CID_DISABLED in case the CID extensions
* were used, but client and server requested the empty CID.
* This is indistinguishable from not using the CID extension
* in the first place. */
if( ssl->transform_in->in_cid_len == 0 &&
ssl->transform_in->out_cid_len == 0 )
{
return( 0 );
}
if( peer_cid_len != NULL )
{
*peer_cid_len = ssl->transform_in->out_cid_len;
if( peer_cid != NULL )
{
memcpy( peer_cid, ssl->transform_in->out_cid,
ssl->transform_in->out_cid_len );
}
}
*enabled = MBEDTLS_SSL_CID_ENABLED;
return( 0 );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
/* Forward declarations for functions related to message buffering. */
static void ssl_buffering_free( mbedtls_ssl_context *ssl );
static void ssl_buffering_free_slot( mbedtls_ssl_context *ssl,
uint8_t slot );
static void ssl_free_buffered_record( mbedtls_ssl_context *ssl );
static int ssl_load_buffered_message( mbedtls_ssl_context *ssl );
static int ssl_load_buffered_record( mbedtls_ssl_context *ssl );
static int ssl_buffer_message( mbedtls_ssl_context *ssl );
static int ssl_buffer_future_record( mbedtls_ssl_context *ssl,
mbedtls_record const *rec );
static int ssl_next_record_is_in_datagram( mbedtls_ssl_context *ssl );
static size_t ssl_get_current_mtu( const mbedtls_ssl_context *ssl );
static size_t ssl_get_maximum_datagram_size( mbedtls_ssl_context const *ssl )
{
size_t mtu = ssl_get_current_mtu( ssl );
if( mtu != 0 && mtu < MBEDTLS_SSL_OUT_BUFFER_LEN )
return( mtu );
return( MBEDTLS_SSL_OUT_BUFFER_LEN );
}
static int ssl_get_remaining_space_in_datagram( mbedtls_ssl_context const *ssl )
{
size_t const bytes_written = ssl->out_left;
size_t const mtu = ssl_get_maximum_datagram_size( ssl );
/* Double-check that the write-index hasn't gone
* past what we can transmit in a single datagram. */
if( bytes_written > mtu )
{
/* Should never happen... */
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
return( (int) ( mtu - bytes_written ) );
}
static int ssl_get_remaining_payload_in_datagram( mbedtls_ssl_context const *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t remaining, expansion;
size_t max_len = MBEDTLS_SSL_OUT_CONTENT_LEN;
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
const size_t mfl = mbedtls_ssl_get_max_frag_len( ssl );
if( max_len > mfl )
max_len = mfl;
/* By the standard (RFC 6066 Sect. 4), the MFL extension
* only limits the maximum record payload size, so in theory
* we would be allowed to pack multiple records of payload size
* MFL into a single datagram. However, this would mean that there's
* no way to explicitly communicate MTU restrictions to the peer.
*
* The following reduction of max_len makes sure that we never
* write datagrams larger than MFL + Record Expansion Overhead.
*/
if( max_len <= ssl->out_left )
return( 0 );
max_len -= ssl->out_left;
#endif
ret = ssl_get_remaining_space_in_datagram( ssl );
if( ret < 0 )
return( ret );
remaining = (size_t) ret;
ret = mbedtls_ssl_get_record_expansion( ssl );
if( ret < 0 )
return( ret );
expansion = (size_t) ret;
if( remaining <= expansion )
return( 0 );
remaining -= expansion;
if( remaining >= max_len )
remaining = max_len;
return( (int) remaining );
}
/*
* Double the retransmit timeout value, within the allowed range,
* returning -1 if the maximum value has already been reached.
*/
static int ssl_double_retransmit_timeout( mbedtls_ssl_context *ssl )
{
uint32_t new_timeout;
if( ssl->handshake->retransmit_timeout >= ssl->conf->hs_timeout_max )
return( -1 );
/* Implement the final paragraph of RFC 6347 section 4.1.1.1
* in the following way: after the initial transmission and a first
* retransmission, back off to a temporary estimated MTU of 508 bytes.
* This value is guaranteed to be deliverable (if not guaranteed to be
* delivered) of any compliant IPv4 (and IPv6) network, and should work
* on most non-IP stacks too. */
if( ssl->handshake->retransmit_timeout != ssl->conf->hs_timeout_min )
{
ssl->handshake->mtu = 508;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "mtu autoreduction to %d bytes", ssl->handshake->mtu ) );
}
new_timeout = 2 * ssl->handshake->retransmit_timeout;
/* Avoid arithmetic overflow and range overflow */
if( new_timeout < ssl->handshake->retransmit_timeout ||
new_timeout > ssl->conf->hs_timeout_max )
{
new_timeout = ssl->conf->hs_timeout_max;
}
ssl->handshake->retransmit_timeout = new_timeout;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "update timeout value to %d millisecs",
ssl->handshake->retransmit_timeout ) );
return( 0 );
}
static void ssl_reset_retransmit_timeout( mbedtls_ssl_context *ssl )
{
ssl->handshake->retransmit_timeout = ssl->conf->hs_timeout_min;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "update timeout value to %d millisecs",
ssl->handshake->retransmit_timeout ) );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
/*
* Convert max_fragment_length codes to length.
* RFC 6066 says:
* enum{
* 2^9(1), 2^10(2), 2^11(3), 2^12(4), (255)
* } MaxFragmentLength;
* and we add 0 -> extension unused
*/
static unsigned int ssl_mfl_code_to_length( int mfl )
{
switch( mfl )
{
case MBEDTLS_SSL_MAX_FRAG_LEN_NONE:
return ( MBEDTLS_TLS_EXT_ADV_CONTENT_LEN );
case MBEDTLS_SSL_MAX_FRAG_LEN_512:
return 512;
case MBEDTLS_SSL_MAX_FRAG_LEN_1024:
return 1024;
case MBEDTLS_SSL_MAX_FRAG_LEN_2048:
return 2048;
case MBEDTLS_SSL_MAX_FRAG_LEN_4096:
return 4096;
default:
return ( MBEDTLS_TLS_EXT_ADV_CONTENT_LEN );
}
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
int mbedtls_ssl_session_copy( mbedtls_ssl_session *dst,
const mbedtls_ssl_session *src )
{
mbedtls_ssl_session_free( dst );
memcpy( dst, src, sizeof( mbedtls_ssl_session ) );
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
if( src->peer_cert != NULL )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
dst->peer_cert = mbedtls_calloc( 1, sizeof(mbedtls_x509_crt) );
if( dst->peer_cert == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
mbedtls_x509_crt_init( dst->peer_cert );
if( ( ret = mbedtls_x509_crt_parse_der( dst->peer_cert, src->peer_cert->raw.p,
src->peer_cert->raw.len ) ) != 0 )
{
mbedtls_free( dst->peer_cert );
dst->peer_cert = NULL;
return( ret );
}
}
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if( src->peer_cert_digest != NULL )
{
dst->peer_cert_digest =
mbedtls_calloc( 1, src->peer_cert_digest_len );
if( dst->peer_cert_digest == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( dst->peer_cert_digest, src->peer_cert_digest,
src->peer_cert_digest_len );
dst->peer_cert_digest_type = src->peer_cert_digest_type;
dst->peer_cert_digest_len = src->peer_cert_digest_len;
}
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
if( src->ticket != NULL )
{
dst->ticket = mbedtls_calloc( 1, src->ticket_len );
if( dst->ticket == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( dst->ticket, src->ticket, src->ticket_len );
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
return( 0 );
}
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
int (*mbedtls_ssl_hw_record_init)( mbedtls_ssl_context *ssl,
const unsigned char *key_enc, const unsigned char *key_dec,
size_t keylen,
const unsigned char *iv_enc, const unsigned char *iv_dec,
size_t ivlen,
const unsigned char *mac_enc, const unsigned char *mac_dec,
size_t maclen ) = NULL;
int (*mbedtls_ssl_hw_record_activate)( mbedtls_ssl_context *ssl, int direction) = NULL;
int (*mbedtls_ssl_hw_record_reset)( mbedtls_ssl_context *ssl ) = NULL;
int (*mbedtls_ssl_hw_record_write)( mbedtls_ssl_context *ssl ) = NULL;
int (*mbedtls_ssl_hw_record_read)( mbedtls_ssl_context *ssl ) = NULL;
int (*mbedtls_ssl_hw_record_finish)( mbedtls_ssl_context *ssl ) = NULL;
#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
/*
* Key material generation
*/
#if defined(MBEDTLS_SSL_PROTO_SSL3)
static int ssl3_prf( const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
int ret = 0;
size_t i;
mbedtls_md5_context md5;
mbedtls_sha1_context sha1;
unsigned char padding[16];
unsigned char sha1sum[20];
((void)label);
mbedtls_md5_init( &md5 );
mbedtls_sha1_init( &sha1 );
/*
* SSLv3:
* block =
* MD5( secret + SHA1( 'A' + secret + random ) ) +
* MD5( secret + SHA1( 'BB' + secret + random ) ) +
* MD5( secret + SHA1( 'CCC' + secret + random ) ) +
* ...
*/
for( i = 0; i < dlen / 16; i++ )
{
memset( padding, (unsigned char) ('A' + i), 1 + i );
if( ( ret = mbedtls_sha1_starts_ret( &sha1 ) ) != 0 )
goto exit;
if( ( ret = mbedtls_sha1_update_ret( &sha1, padding, 1 + i ) ) != 0 )
goto exit;
if( ( ret = mbedtls_sha1_update_ret( &sha1, secret, slen ) ) != 0 )
goto exit;
if( ( ret = mbedtls_sha1_update_ret( &sha1, random, rlen ) ) != 0 )
goto exit;
if( ( ret = mbedtls_sha1_finish_ret( &sha1, sha1sum ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md5_starts_ret( &md5 ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md5_update_ret( &md5, secret, slen ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md5_update_ret( &md5, sha1sum, 20 ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md5_finish_ret( &md5, dstbuf + i * 16 ) ) != 0 )
goto exit;
}
exit:
mbedtls_md5_free( &md5 );
mbedtls_sha1_free( &sha1 );
mbedtls_platform_zeroize( padding, sizeof( padding ) );
mbedtls_platform_zeroize( sha1sum, sizeof( sha1sum ) );
return( ret );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
static int tls1_prf( const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
size_t nb, hs;
size_t i, j, k;
const unsigned char *S1, *S2;
unsigned char *tmp;
size_t tmp_len = 0;
unsigned char h_i[20];
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_md_init( &md_ctx );
tmp_len = 20 + strlen( label ) + rlen;
tmp = mbedtls_calloc( 1, tmp_len );
if( tmp == NULL )
{
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto exit;
}
hs = ( slen + 1 ) / 2;
S1 = secret;
S2 = secret + slen - hs;
nb = strlen( label );
memcpy( tmp + 20, label, nb );
memcpy( tmp + 20 + nb, random, rlen );
nb += rlen;
/*
* First compute P_md5(secret,label+random)[0..dlen]
*/
if( ( md_info = mbedtls_md_info_from_type( MBEDTLS_MD_MD5 ) ) == NULL )
{
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto exit;
}
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
{
goto exit;
}
mbedtls_md_hmac_starts( &md_ctx, S1, hs );
mbedtls_md_hmac_update( &md_ctx, tmp + 20, nb );
mbedtls_md_hmac_finish( &md_ctx, 4 + tmp );
for( i = 0; i < dlen; i += 16 )
{
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, 4 + tmp, 16 + nb );
mbedtls_md_hmac_finish( &md_ctx, h_i );
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, 4 + tmp, 16 );
mbedtls_md_hmac_finish( &md_ctx, 4 + tmp );
k = ( i + 16 > dlen ) ? dlen % 16 : 16;
for( j = 0; j < k; j++ )
dstbuf[i + j] = h_i[j];
}
mbedtls_md_free( &md_ctx );
/*
* XOR out with P_sha1(secret,label+random)[0..dlen]
*/
if( ( md_info = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 ) ) == NULL )
{
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto exit;
}
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
{
goto exit;
}
mbedtls_md_hmac_starts( &md_ctx, S2, hs );
mbedtls_md_hmac_update( &md_ctx, tmp + 20, nb );
mbedtls_md_hmac_finish( &md_ctx, tmp );
for( i = 0; i < dlen; i += 20 )
{
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, tmp, 20 + nb );
mbedtls_md_hmac_finish( &md_ctx, h_i );
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, tmp, 20 );
mbedtls_md_hmac_finish( &md_ctx, tmp );
k = ( i + 20 > dlen ) ? dlen % 20 : 20;
for( j = 0; j < k; j++ )
dstbuf[i + j] = (unsigned char)( dstbuf[i + j] ^ h_i[j] );
}
exit:
mbedtls_md_free( &md_ctx );
mbedtls_platform_zeroize( tmp, tmp_len );
mbedtls_platform_zeroize( h_i, sizeof( h_i ) );
mbedtls_free( tmp );
return( ret );
}
#endif /* MBEDTLS_SSL_PROTO_TLS1) || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
static psa_status_t setup_psa_key_derivation( psa_key_derivation_operation_t* derivation,
psa_key_handle_t slot,
psa_algorithm_t alg,
const unsigned char* seed, size_t seed_length,
const unsigned char* label, size_t label_length,
size_t capacity )
{
psa_status_t status;
status = psa_key_derivation_setup( derivation, alg );
if( status != PSA_SUCCESS )
return( status );
if( PSA_ALG_IS_TLS12_PRF( alg ) || PSA_ALG_IS_TLS12_PSK_TO_MS( alg ) )
{
status = psa_key_derivation_input_bytes( derivation,
PSA_KEY_DERIVATION_INPUT_SEED,
seed, seed_length );
if( status != PSA_SUCCESS )
return( status );
if( slot == 0 )
{
status = psa_key_derivation_input_bytes(
derivation, PSA_KEY_DERIVATION_INPUT_SECRET,
NULL, 0 );
}
else
{
status = psa_key_derivation_input_key(
derivation, PSA_KEY_DERIVATION_INPUT_SECRET,
slot );
}
if( status != PSA_SUCCESS )
return( status );
status = psa_key_derivation_input_bytes( derivation,
PSA_KEY_DERIVATION_INPUT_LABEL,
label, label_length );
if( status != PSA_SUCCESS )
return( status );
}
else
{
return( PSA_ERROR_NOT_SUPPORTED );
}
status = psa_key_derivation_set_capacity( derivation, capacity );
if( status != PSA_SUCCESS )
return( status );
return( PSA_SUCCESS );
}
static int tls_prf_generic( mbedtls_md_type_t md_type,
const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
psa_status_t status;
psa_algorithm_t alg;
psa_key_handle_t master_slot = 0;
psa_key_derivation_operation_t derivation =
PSA_KEY_DERIVATION_OPERATION_INIT;
if( md_type == MBEDTLS_MD_SHA384 )
alg = PSA_ALG_TLS12_PRF(PSA_ALG_SHA_384);
else
alg = PSA_ALG_TLS12_PRF(PSA_ALG_SHA_256);
/* Normally a "secret" should be long enough to be impossible to
* find by brute force, and in particular should not be empty. But
* this PRF is also used to derive an IV, in particular in EAP-TLS,
* and for this use case it makes sense to have a 0-length "secret".
* Since the key API doesn't allow importing a key of length 0,
* keep master_slot=0, which setup_psa_key_derivation() understands
* to mean a 0-length "secret" input. */
if( slen != 0 )
{
psa_key_attributes_t key_attributes = psa_key_attributes_init();
psa_set_key_usage_flags( &key_attributes, PSA_KEY_USAGE_DERIVE );
psa_set_key_algorithm( &key_attributes, alg );
psa_set_key_type( &key_attributes, PSA_KEY_TYPE_DERIVE );
status = psa_import_key( &key_attributes, secret, slen, &master_slot );
if( status != PSA_SUCCESS )
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
status = setup_psa_key_derivation( &derivation,
master_slot, alg,
random, rlen,
(unsigned char const *) label,
(size_t) strlen( label ),
dlen );
if( status != PSA_SUCCESS )
{
psa_key_derivation_abort( &derivation );
psa_destroy_key( master_slot );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
status = psa_key_derivation_output_bytes( &derivation, dstbuf, dlen );
if( status != PSA_SUCCESS )
{
psa_key_derivation_abort( &derivation );
psa_destroy_key( master_slot );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
status = psa_key_derivation_abort( &derivation );
if( status != PSA_SUCCESS )
{
psa_destroy_key( master_slot );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
if( master_slot != 0 )
status = psa_destroy_key( master_slot );
if( status != PSA_SUCCESS )
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
return( 0 );
}
#else /* MBEDTLS_USE_PSA_CRYPTO */
static int tls_prf_generic( mbedtls_md_type_t md_type,
const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
size_t nb;
size_t i, j, k, md_len;
unsigned char *tmp;
size_t tmp_len = 0;
unsigned char h_i[MBEDTLS_MD_MAX_SIZE];
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_md_init( &md_ctx );
if( ( md_info = mbedtls_md_info_from_type( md_type ) ) == NULL )
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
md_len = mbedtls_md_get_size( md_info );
tmp_len = md_len + strlen( label ) + rlen;
tmp = mbedtls_calloc( 1, tmp_len );
if( tmp == NULL )
{
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto exit;
}
nb = strlen( label );
memcpy( tmp + md_len, label, nb );
memcpy( tmp + md_len + nb, random, rlen );
nb += rlen;
/*
* Compute P_<hash>(secret, label + random)[0..dlen]
*/
if ( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
goto exit;
mbedtls_md_hmac_starts( &md_ctx, secret, slen );
mbedtls_md_hmac_update( &md_ctx, tmp + md_len, nb );
mbedtls_md_hmac_finish( &md_ctx, tmp );
for( i = 0; i < dlen; i += md_len )
{
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, tmp, md_len + nb );
mbedtls_md_hmac_finish( &md_ctx, h_i );
mbedtls_md_hmac_reset ( &md_ctx );
mbedtls_md_hmac_update( &md_ctx, tmp, md_len );
mbedtls_md_hmac_finish( &md_ctx, tmp );
k = ( i + md_len > dlen ) ? dlen % md_len : md_len;
for( j = 0; j < k; j++ )
dstbuf[i + j] = h_i[j];
}
exit:
mbedtls_md_free( &md_ctx );
mbedtls_platform_zeroize( tmp, tmp_len );
mbedtls_platform_zeroize( h_i, sizeof( h_i ) );
mbedtls_free( tmp );
return( ret );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#if defined(MBEDTLS_SHA256_C)
static int tls_prf_sha256( const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
return( tls_prf_generic( MBEDTLS_MD_SHA256, secret, slen,
label, random, rlen, dstbuf, dlen ) );
}
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
static int tls_prf_sha384( const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
return( tls_prf_generic( MBEDTLS_MD_SHA384, secret, slen,
label, random, rlen, dstbuf, dlen ) );
}
#endif /* MBEDTLS_SHA512_C */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
static void ssl_update_checksum_start( mbedtls_ssl_context *, const unsigned char *, size_t );
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
static void ssl_update_checksum_md5sha1( mbedtls_ssl_context *, const unsigned char *, size_t );
#endif
#if defined(MBEDTLS_SSL_PROTO_SSL3)
static void ssl_calc_verify_ssl( const mbedtls_ssl_context *, unsigned char *, size_t * );
static void ssl_calc_finished_ssl( mbedtls_ssl_context *, unsigned char *, int );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
static void ssl_calc_verify_tls( const mbedtls_ssl_context *, unsigned char *, size_t * );
static void ssl_calc_finished_tls( mbedtls_ssl_context *, unsigned char *, int );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
static void ssl_update_checksum_sha256( mbedtls_ssl_context *, const unsigned char *, size_t );
static void ssl_calc_verify_tls_sha256( const mbedtls_ssl_context *,unsigned char *, size_t * );
static void ssl_calc_finished_tls_sha256( mbedtls_ssl_context *,unsigned char *, int );
#endif
#if defined(MBEDTLS_SHA512_C)
static void ssl_update_checksum_sha384( mbedtls_ssl_context *, const unsigned char *, size_t );
static void ssl_calc_verify_tls_sha384( const mbedtls_ssl_context *, unsigned char *, size_t * );
static void ssl_calc_finished_tls_sha384( mbedtls_ssl_context *, unsigned char *, int );
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) && \
defined(MBEDTLS_USE_PSA_CRYPTO)
static int ssl_use_opaque_psk( mbedtls_ssl_context const *ssl )
{
if( ssl->conf->f_psk != NULL )
{
/* If we've used a callback to select the PSK,
* the static configuration is irrelevant. */
if( ssl->handshake->psk_opaque != 0 )
return( 1 );
return( 0 );
}
if( ssl->conf->psk_opaque != 0 )
return( 1 );
return( 0 );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */
#if defined(MBEDTLS_SSL_EXPORT_KEYS)
static mbedtls_tls_prf_types tls_prf_get_type( mbedtls_ssl_tls_prf_cb *tls_prf )
{
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( tls_prf == ssl3_prf )
{
return( MBEDTLS_SSL_TLS_PRF_SSL3 );
}
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( tls_prf == tls1_prf )
{
return( MBEDTLS_SSL_TLS_PRF_TLS1 );
}
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA512_C)
if( tls_prf == tls_prf_sha384 )
{
return( MBEDTLS_SSL_TLS_PRF_SHA384 );
}
else
#endif
#if defined(MBEDTLS_SHA256_C)
if( tls_prf == tls_prf_sha256 )
{
return( MBEDTLS_SSL_TLS_PRF_SHA256 );
}
else
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
return( MBEDTLS_SSL_TLS_PRF_NONE );
}
#endif /* MBEDTLS_SSL_EXPORT_KEYS */
int mbedtls_ssl_tls_prf( const mbedtls_tls_prf_types prf,
const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
mbedtls_ssl_tls_prf_cb *tls_prf = NULL;
switch( prf )
{
#if defined(MBEDTLS_SSL_PROTO_SSL3)
case MBEDTLS_SSL_TLS_PRF_SSL3:
tls_prf = ssl3_prf;
break;
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
case MBEDTLS_SSL_TLS_PRF_TLS1:
tls_prf = tls1_prf;
break;
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_SSL_TLS_PRF_SHA384:
tls_prf = tls_prf_sha384;
break;
#endif /* MBEDTLS_SHA512_C */
#if defined(MBEDTLS_SHA256_C)
case MBEDTLS_SSL_TLS_PRF_SHA256:
tls_prf = tls_prf_sha256;
break;
#endif /* MBEDTLS_SHA256_C */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
default:
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
return( tls_prf( secret, slen, label, random, rlen, dstbuf, dlen ) );
}
/* Type for the TLS PRF */
typedef int ssl_tls_prf_t(const unsigned char *, size_t, const char *,
const unsigned char *, size_t,
unsigned char *, size_t);
/*
* Populate a transform structure with session keys and all the other
* necessary information.
*
* Parameters:
* - [in/out]: transform: structure to populate
* [in] must be just initialised with mbedtls_ssl_transform_init()
* [out] fully populated, ready for use by mbedtls_ssl_{en,de}crypt_buf()
* - [in] ciphersuite
* - [in] master
* - [in] encrypt_then_mac
* - [in] trunc_hmac
* - [in] compression
* - [in] tls_prf: pointer to PRF to use for key derivation
* - [in] randbytes: buffer holding ServerHello.random + ClientHello.random
* - [in] minor_ver: SSL/TLS minor version
* - [in] endpoint: client or server
* - [in] ssl: optionally used for:
* - MBEDTLS_SSL_HW_RECORD_ACCEL: whole context
* - MBEDTLS_SSL_EXPORT_KEYS: ssl->conf->{f,p}_export_keys
* - MBEDTLS_DEBUG_C: ssl->conf->{f,p}_dbg
*/
static int ssl_populate_transform( mbedtls_ssl_transform *transform,
int ciphersuite,
const unsigned char master[48],
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
int encrypt_then_mac,
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
int trunc_hmac,
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
#if defined(MBEDTLS_ZLIB_SUPPORT)
int compression,
#endif
ssl_tls_prf_t tls_prf,
const unsigned char randbytes[64],
int minor_ver,
unsigned endpoint,
const mbedtls_ssl_context *ssl )
{
int ret = 0;
#if defined(MBEDTLS_USE_PSA_CRYPTO)
int psa_fallthrough;
#endif /* MBEDTLS_USE_PSA_CRYPTO */
unsigned char keyblk[256];
unsigned char *key1;
unsigned char *key2;
unsigned char *mac_enc;
unsigned char *mac_dec;
size_t mac_key_len;
size_t iv_copy_len;
unsigned keylen;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
const mbedtls_cipher_info_t *cipher_info;
const mbedtls_md_info_t *md_info;
#if !defined(MBEDTLS_SSL_HW_RECORD_ACCEL) && \
!defined(MBEDTLS_SSL_EXPORT_KEYS) && \
!defined(MBEDTLS_DEBUG_C)
ssl = NULL; /* make sure we don't use it except for those cases */
(void) ssl;
#endif
/*
* Some data just needs copying into the structure
*/
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) && \
defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
transform->encrypt_then_mac = encrypt_then_mac;
#endif
transform->minor_ver = minor_ver;
#if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
memcpy( transform->randbytes, randbytes, sizeof( transform->randbytes ) );
#endif
/*
* Get various info structures
*/
ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( ciphersuite );
if( ciphersuite_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "ciphersuite info for %d not found",
ciphersuite ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
cipher_info = mbedtls_cipher_info_from_type( ciphersuite_info->cipher );
if( cipher_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "cipher info for %d not found",
ciphersuite_info->cipher ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
md_info = mbedtls_md_info_from_type( ciphersuite_info->mac );
if( md_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "mbedtls_md info for %d not found",
ciphersuite_info->mac ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* Copy own and peer's CID if the use of the CID
* extension has been negotiated. */
if( ssl->handshake->cid_in_use == MBEDTLS_SSL_CID_ENABLED )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Copy CIDs into SSL transform" ) );
transform->in_cid_len = ssl->own_cid_len;
memcpy( transform->in_cid, ssl->own_cid, ssl->own_cid_len );
MBEDTLS_SSL_DEBUG_BUF( 3, "Incoming CID", transform->in_cid,
transform->in_cid_len );
transform->out_cid_len = ssl->handshake->peer_cid_len;
memcpy( transform->out_cid, ssl->handshake->peer_cid,
ssl->handshake->peer_cid_len );
MBEDTLS_SSL_DEBUG_BUF( 3, "Outgoing CID", transform->out_cid,
transform->out_cid_len );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
/*
* Compute key block using the PRF
*/
ret = tls_prf( master, 48, "key expansion", randbytes, 64, keyblk, 256 );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "prf", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite = %s",
mbedtls_ssl_get_ciphersuite_name( ciphersuite ) ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "master secret", master, 48 );
MBEDTLS_SSL_DEBUG_BUF( 4, "random bytes", randbytes, 64 );
MBEDTLS_SSL_DEBUG_BUF( 4, "key block", keyblk, 256 );
/*
* Determine the appropriate key, IV and MAC length.
*/
keylen = cipher_info->key_bitlen / 8;
#if defined(MBEDTLS_GCM_C) || \
defined(MBEDTLS_CCM_C) || \
defined(MBEDTLS_CHACHAPOLY_C)
if( cipher_info->mode == MBEDTLS_MODE_GCM ||
cipher_info->mode == MBEDTLS_MODE_CCM ||
cipher_info->mode == MBEDTLS_MODE_CHACHAPOLY )
{
size_t explicit_ivlen;
transform->maclen = 0;
mac_key_len = 0;
transform->taglen =
ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
/* All modes haves 96-bit IVs;
* GCM and CCM has 4 implicit and 8 explicit bytes
* ChachaPoly has all 12 bytes implicit
*/
transform->ivlen = 12;
if( cipher_info->mode == MBEDTLS_MODE_CHACHAPOLY )
transform->fixed_ivlen = 12;
else
transform->fixed_ivlen = 4;
/* Minimum length of encrypted record */
explicit_ivlen = transform->ivlen - transform->fixed_ivlen;
transform->minlen = explicit_ivlen + transform->taglen;
}
else
#endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C || MBEDTLS_CHACHAPOLY_C */
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
if( cipher_info->mode == MBEDTLS_MODE_STREAM ||
cipher_info->mode == MBEDTLS_MODE_CBC )
{
/* Initialize HMAC contexts */
if( ( ret = mbedtls_md_setup( &transform->md_ctx_enc, md_info, 1 ) ) != 0 ||
( ret = mbedtls_md_setup( &transform->md_ctx_dec, md_info, 1 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_setup", ret );
goto end;
}
/* Get MAC length */
mac_key_len = mbedtls_md_get_size( md_info );
transform->maclen = mac_key_len;
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
/*
* If HMAC is to be truncated, we shall keep the leftmost bytes,
* (rfc 6066 page 13 or rfc 2104 section 4),
* so we only need to adjust the length here.
*/
if( trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_ENABLED )
{
transform->maclen = MBEDTLS_SSL_TRUNCATED_HMAC_LEN;
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC_COMPAT)
/* Fall back to old, non-compliant version of the truncated
* HMAC implementation which also truncates the key
* (Mbed TLS versions from 1.3 to 2.6.0) */
mac_key_len = transform->maclen;
#endif
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
/* IV length */
transform->ivlen = cipher_info->iv_size;
/* Minimum length */
if( cipher_info->mode == MBEDTLS_MODE_STREAM )
transform->minlen = transform->maclen;
else
{
/*
* GenericBlockCipher:
* 1. if EtM is in use: one block plus MAC
* otherwise: * first multiple of blocklen greater than maclen
* 2. IV except for SSL3 and TLS 1.0
*/
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if( encrypt_then_mac == MBEDTLS_SSL_ETM_ENABLED )
{
transform->minlen = transform->maclen
+ cipher_info->block_size;
}
else
#endif
{
transform->minlen = transform->maclen
+ cipher_info->block_size
- transform->maclen % cipher_info->block_size;
}
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
minor_ver == MBEDTLS_SSL_MINOR_VERSION_1 )
; /* No need to adjust minlen */
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_2 ||
minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
transform->minlen += transform->ivlen;
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto end;
}
}
}
else
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "keylen: %u, minlen: %u, ivlen: %u, maclen: %u",
(unsigned) keylen,
(unsigned) transform->minlen,
(unsigned) transform->ivlen,
(unsigned) transform->maclen ) );
/*
* Finally setup the cipher contexts, IVs and MAC secrets.
*/
#if defined(MBEDTLS_SSL_CLI_C)
if( endpoint == MBEDTLS_SSL_IS_CLIENT )
{
key1 = keyblk + mac_key_len * 2;
key2 = keyblk + mac_key_len * 2 + keylen;
mac_enc = keyblk;
mac_dec = keyblk + mac_key_len;
/*
* This is not used in TLS v1.1.
*/
iv_copy_len = ( transform->fixed_ivlen ) ?
transform->fixed_ivlen : transform->ivlen;
memcpy( transform->iv_enc, key2 + keylen, iv_copy_len );
memcpy( transform->iv_dec, key2 + keylen + iv_copy_len,
iv_copy_len );
}
else
#endif /* MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_SSL_SRV_C)
if( endpoint == MBEDTLS_SSL_IS_SERVER )
{
key1 = keyblk + mac_key_len * 2 + keylen;
key2 = keyblk + mac_key_len * 2;
mac_enc = keyblk + mac_key_len;
mac_dec = keyblk;
/*
* This is not used in TLS v1.1.
*/
iv_copy_len = ( transform->fixed_ivlen ) ?
transform->fixed_ivlen : transform->ivlen;
memcpy( transform->iv_dec, key1 + keylen, iv_copy_len );
memcpy( transform->iv_enc, key1 + keylen + iv_copy_len,
iv_copy_len );
}
else
#endif /* MBEDTLS_SSL_SRV_C */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto end;
}
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
if( mac_key_len > sizeof( transform->mac_enc ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto end;
}
memcpy( transform->mac_enc, mac_enc, mac_key_len );
memcpy( transform->mac_dec, mac_dec, mac_key_len );
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 )
{
/* For HMAC-based ciphersuites, initialize the HMAC transforms.
For AEAD-based ciphersuites, there is nothing to do here. */
if( mac_key_len != 0 )
{
mbedtls_md_hmac_starts( &transform->md_ctx_enc, mac_enc, mac_key_len );
mbedtls_md_hmac_starts( &transform->md_ctx_dec, mac_dec, mac_key_len );
}
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
goto end;
}
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_init != NULL )
{
int ret = 0;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_init()" ) );
if( ( ret = mbedtls_ssl_hw_record_init( ssl, key1, key2, keylen,
transform->iv_enc, transform->iv_dec,
iv_copy_len,
mac_enc, mac_dec,
mac_key_len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_init", ret );
ret = MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
goto end;
}
}
#else
((void) mac_dec);
((void) mac_enc);
#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
#if defined(MBEDTLS_SSL_EXPORT_KEYS)
if( ssl->conf->f_export_keys != NULL )
{
ssl->conf->f_export_keys( ssl->conf->p_export_keys,
master, keyblk,
mac_key_len, keylen,
iv_copy_len );
}
if( ssl->conf->f_export_keys_ext != NULL )
{
ssl->conf->f_export_keys_ext( ssl->conf->p_export_keys,
master, keyblk,
mac_key_len, keylen,
iv_copy_len,
randbytes + 32,
randbytes,
tls_prf_get_type( tls_prf ) );
}
#endif
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Only use PSA-based ciphers for TLS-1.2.
* That's relevant at least for TLS-1.0, where
* we assume that mbedtls_cipher_crypt() updates
* the structure field for the IV, which the PSA-based
* implementation currently doesn't. */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
ret = mbedtls_cipher_setup_psa( &transform->cipher_ctx_enc,
cipher_info, transform->taglen );
if( ret != 0 && ret != MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup_psa", ret );
goto end;
}
if( ret == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Successfully setup PSA-based encryption cipher context" ) );
psa_fallthrough = 0;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Failed to setup PSA-based cipher context for record encryption - fall through to default setup." ) );
psa_fallthrough = 1;
}
}
else
psa_fallthrough = 1;
#else
psa_fallthrough = 1;
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
if( psa_fallthrough == 1 )
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if( ( ret = mbedtls_cipher_setup( &transform->cipher_ctx_enc,
cipher_info ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup", ret );
goto end;
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Only use PSA-based ciphers for TLS-1.2.
* That's relevant at least for TLS-1.0, where
* we assume that mbedtls_cipher_crypt() updates
* the structure field for the IV, which the PSA-based
* implementation currently doesn't. */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
ret = mbedtls_cipher_setup_psa( &transform->cipher_ctx_dec,
cipher_info, transform->taglen );
if( ret != 0 && ret != MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup_psa", ret );
goto end;
}
if( ret == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Successfully setup PSA-based decryption cipher context" ) );
psa_fallthrough = 0;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Failed to setup PSA-based cipher context for record decryption - fall through to default setup." ) );
psa_fallthrough = 1;
}
}
else
psa_fallthrough = 1;
#else
psa_fallthrough = 1;
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
if( psa_fallthrough == 1 )
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if( ( ret = mbedtls_cipher_setup( &transform->cipher_ctx_dec,
cipher_info ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup", ret );
goto end;
}
if( ( ret = mbedtls_cipher_setkey( &transform->cipher_ctx_enc, key1,
cipher_info->key_bitlen,
MBEDTLS_ENCRYPT ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setkey", ret );
goto end;
}
if( ( ret = mbedtls_cipher_setkey( &transform->cipher_ctx_dec, key2,
cipher_info->key_bitlen,
MBEDTLS_DECRYPT ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setkey", ret );
goto end;
}
#if defined(MBEDTLS_CIPHER_MODE_CBC)
if( cipher_info->mode == MBEDTLS_MODE_CBC )
{
if( ( ret = mbedtls_cipher_set_padding_mode( &transform->cipher_ctx_enc,
MBEDTLS_PADDING_NONE ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_set_padding_mode", ret );
goto end;
}
if( ( ret = mbedtls_cipher_set_padding_mode( &transform->cipher_ctx_dec,
MBEDTLS_PADDING_NONE ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_set_padding_mode", ret );
goto end;
}
}
#endif /* MBEDTLS_CIPHER_MODE_CBC */
/* Initialize Zlib contexts */
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( compression == MBEDTLS_SSL_COMPRESS_DEFLATE )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Initializing zlib states" ) );
memset( &transform->ctx_deflate, 0, sizeof( transform->ctx_deflate ) );
memset( &transform->ctx_inflate, 0, sizeof( transform->ctx_inflate ) );
if( deflateInit( &transform->ctx_deflate,
Z_DEFAULT_COMPRESSION ) != Z_OK ||
inflateInit( &transform->ctx_inflate ) != Z_OK )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Failed to initialize compression" ) );
ret = MBEDTLS_ERR_SSL_COMPRESSION_FAILED;
goto end;
}
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
end:
mbedtls_platform_zeroize( keyblk, sizeof( keyblk ) );
return( ret );
}
/*
* Set appropriate PRF function and other SSL / TLS 1.0/1.1 / TLS1.2 functions
*
* Inputs:
* - SSL/TLS minor version
* - hash associated with the ciphersuite (only used by TLS 1.2)
*
* Outputs:
* - the tls_prf, calc_verify and calc_finished members of handshake structure
*/
static int ssl_set_handshake_prfs( mbedtls_ssl_handshake_params *handshake,
int minor_ver,
mbedtls_md_type_t hash )
{
#if !defined(MBEDTLS_SSL_PROTO_TLS1_2) || !defined(MBEDTLS_SHA512_C)
(void) hash;
#endif
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
handshake->tls_prf = ssl3_prf;
handshake->calc_verify = ssl_calc_verify_ssl;
handshake->calc_finished = ssl_calc_finished_ssl;
}
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 )
{
handshake->tls_prf = tls1_prf;
handshake->calc_verify = ssl_calc_verify_tls;
handshake->calc_finished = ssl_calc_finished_tls;
}
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA512_C)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
hash == MBEDTLS_MD_SHA384 )
{
handshake->tls_prf = tls_prf_sha384;
handshake->calc_verify = ssl_calc_verify_tls_sha384;
handshake->calc_finished = ssl_calc_finished_tls_sha384;
}
else
#endif
#if defined(MBEDTLS_SHA256_C)
if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
handshake->tls_prf = tls_prf_sha256;
handshake->calc_verify = ssl_calc_verify_tls_sha256;
handshake->calc_finished = ssl_calc_finished_tls_sha256;
}
else
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
{
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
return( 0 );
}
/*
* Compute master secret if needed
*
* Parameters:
* [in/out] handshake
* [in] resume, premaster, extended_ms, calc_verify, tls_prf
* (PSA-PSK) ciphersuite_info, psk_opaque
* [out] premaster (cleared)
* [out] master
* [in] ssl: optionally used for debugging, EMS and PSA-PSK
* debug: conf->f_dbg, conf->p_dbg
* EMS: passed to calc_verify (debug + (SSL3) session_negotiate)
* PSA-PSA: minor_ver, conf
*/
static int ssl_compute_master( mbedtls_ssl_handshake_params *handshake,
unsigned char *master,
const mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/* cf. RFC 5246, Section 8.1:
* "The master secret is always exactly 48 bytes in length." */
size_t const master_secret_len = 48;
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
unsigned char session_hash[48];
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
/* The label for the KDF used for key expansion.
* This is either "master secret" or "extended master secret"
* depending on whether the Extended Master Secret extension
* is used. */
char const *lbl = "master secret";
/* The salt for the KDF used for key expansion.
* - If the Extended Master Secret extension is not used,
* this is ClientHello.Random + ServerHello.Random
* (see Sect. 8.1 in RFC 5246).
* - If the Extended Master Secret extension is used,
* this is the transcript of the handshake so far.
* (see Sect. 4 in RFC 7627). */
unsigned char const *salt = handshake->randbytes;
size_t salt_len = 64;
#if !defined(MBEDTLS_DEBUG_C) && \
!defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) && \
!(defined(MBEDTLS_USE_PSA_CRYPTO) && \
defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED))
ssl = NULL; /* make sure we don't use it except for those cases */
(void) ssl;
#endif
if( handshake->resume != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no premaster (session resumed)" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
if( handshake->extended_ms == MBEDTLS_SSL_EXTENDED_MS_ENABLED )
{
lbl = "extended master secret";
salt = session_hash;
handshake->calc_verify( ssl, session_hash, &salt_len );
MBEDTLS_SSL_DEBUG_BUF( 3, "session hash for extended master secret",
session_hash, salt_len );
}
#endif /* MBEDTLS_SSL_EXTENDED_MS_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if( handshake->ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK &&
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
ssl_use_opaque_psk( ssl ) == 1 )
{
/* Perform PSK-to-MS expansion in a single step. */
psa_status_t status;
psa_algorithm_t alg;
psa_key_handle_t psk;
psa_key_derivation_operation_t derivation =
PSA_KEY_DERIVATION_OPERATION_INIT;
mbedtls_md_type_t hash_alg = handshake->ciphersuite_info->mac;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "perform PSA-based PSK-to-MS expansion" ) );
psk = ssl->conf->psk_opaque;
if( handshake->psk_opaque != 0 )
psk = handshake->psk_opaque;
if( hash_alg == MBEDTLS_MD_SHA384 )
alg = PSA_ALG_TLS12_PSK_TO_MS(PSA_ALG_SHA_384);
else
alg = PSA_ALG_TLS12_PSK_TO_MS(PSA_ALG_SHA_256);
status = setup_psa_key_derivation( &derivation, psk, alg,
salt, salt_len,
(unsigned char const *) lbl,
(size_t) strlen( lbl ),
master_secret_len );
if( status != PSA_SUCCESS )
{
psa_key_derivation_abort( &derivation );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
status = psa_key_derivation_output_bytes( &derivation,
master,
master_secret_len );
if( status != PSA_SUCCESS )
{
psa_key_derivation_abort( &derivation );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
status = psa_key_derivation_abort( &derivation );
if( status != PSA_SUCCESS )
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
else
#endif
{
ret = handshake->tls_prf( handshake->premaster, handshake->pmslen,
lbl, salt, salt_len,
master,
master_secret_len );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "prf", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_BUF( 3, "premaster secret",
handshake->premaster,
handshake->pmslen );
mbedtls_platform_zeroize( handshake->premaster,
sizeof(handshake->premaster) );
}
return( 0 );
}
int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
const mbedtls_ssl_ciphersuite_t * const ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> derive keys" ) );
/* Set PRF, calc_verify and calc_finished function pointers */
ret = ssl_set_handshake_prfs( ssl->handshake,
ssl->minor_ver,
ciphersuite_info->mac );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_set_handshake_prfs", ret );
return( ret );
}
/* Compute master secret if needed */
ret = ssl_compute_master( ssl->handshake,
ssl->session_negotiate->master,
ssl );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_compute_master", ret );
return( ret );
}
/* Swap the client and server random values:
* - MS derivation wanted client+server (RFC 5246 8.1)
* - key derivation wants server+client (RFC 5246 6.3) */
{
unsigned char tmp[64];
memcpy( tmp, ssl->handshake->randbytes, 64 );
memcpy( ssl->handshake->randbytes, tmp + 32, 32 );
memcpy( ssl->handshake->randbytes + 32, tmp, 32 );
mbedtls_platform_zeroize( tmp, sizeof( tmp ) );
}
/* Populate transform structure */
ret = ssl_populate_transform( ssl->transform_negotiate,
ssl->session_negotiate->ciphersuite,
ssl->session_negotiate->master,
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
ssl->session_negotiate->encrypt_then_mac,
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
ssl->session_negotiate->trunc_hmac,
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
#if defined(MBEDTLS_ZLIB_SUPPORT)
ssl->session_negotiate->compression,
#endif
ssl->handshake->tls_prf,
ssl->handshake->randbytes,
ssl->minor_ver,
ssl->conf->endpoint,
ssl );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_populate_transform", ret );
return( ret );
}
/* We no longer need Server/ClientHello.random values */
mbedtls_platform_zeroize( ssl->handshake->randbytes,
sizeof( ssl->handshake->randbytes ) );
/* Allocate compression buffer */
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( ssl->session_negotiate->compression == MBEDTLS_SSL_COMPRESS_DEFLATE &&
ssl->compress_buf == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Allocating compression buffer" ) );
ssl->compress_buf = mbedtls_calloc( 1, MBEDTLS_SSL_COMPRESS_BUFFER_LEN );
if( ssl->compress_buf == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed",
MBEDTLS_SSL_COMPRESS_BUFFER_LEN ) );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
}
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= derive keys" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
void ssl_calc_verify_ssl( const mbedtls_ssl_context *ssl,
unsigned char hash[36],
size_t *hlen )
{
mbedtls_md5_context md5;
mbedtls_sha1_context sha1;
unsigned char pad_1[48];
unsigned char pad_2[48];
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc verify ssl" ) );
mbedtls_md5_init( &md5 );
mbedtls_sha1_init( &sha1 );
mbedtls_md5_clone( &md5, &ssl->handshake->fin_md5 );
mbedtls_sha1_clone( &sha1, &ssl->handshake->fin_sha1 );
memset( pad_1, 0x36, 48 );
memset( pad_2, 0x5C, 48 );
mbedtls_md5_update_ret( &md5, ssl->session_negotiate->master, 48 );
mbedtls_md5_update_ret( &md5, pad_1, 48 );
mbedtls_md5_finish_ret( &md5, hash );
mbedtls_md5_starts_ret( &md5 );
mbedtls_md5_update_ret( &md5, ssl->session_negotiate->master, 48 );
mbedtls_md5_update_ret( &md5, pad_2, 48 );
mbedtls_md5_update_ret( &md5, hash, 16 );
mbedtls_md5_finish_ret( &md5, hash );
mbedtls_sha1_update_ret( &sha1, ssl->session_negotiate->master, 48 );
mbedtls_sha1_update_ret( &sha1, pad_1, 40 );
mbedtls_sha1_finish_ret( &sha1, hash + 16 );
mbedtls_sha1_starts_ret( &sha1 );
mbedtls_sha1_update_ret( &sha1, ssl->session_negotiate->master, 48 );
mbedtls_sha1_update_ret( &sha1, pad_2, 40 );
mbedtls_sha1_update_ret( &sha1, hash + 16, 20 );
mbedtls_sha1_finish_ret( &sha1, hash + 16 );
*hlen = 36;
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_md5_free( &md5 );
mbedtls_sha1_free( &sha1 );
return;
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
void ssl_calc_verify_tls( const mbedtls_ssl_context *ssl,
unsigned char hash[36],
size_t *hlen )
{
mbedtls_md5_context md5;
mbedtls_sha1_context sha1;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc verify tls" ) );
mbedtls_md5_init( &md5 );
mbedtls_sha1_init( &sha1 );
mbedtls_md5_clone( &md5, &ssl->handshake->fin_md5 );
mbedtls_sha1_clone( &sha1, &ssl->handshake->fin_sha1 );
mbedtls_md5_finish_ret( &md5, hash );
mbedtls_sha1_finish_ret( &sha1, hash + 16 );
*hlen = 36;
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_md5_free( &md5 );
mbedtls_sha1_free( &sha1 );
return;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
void ssl_calc_verify_tls_sha256( const mbedtls_ssl_context *ssl,
unsigned char hash[32],
size_t *hlen )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
size_t hash_size;
psa_status_t status;
psa_hash_operation_t sha256_psa = psa_hash_operation_init();
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> PSA calc verify sha256" ) );
status = psa_hash_clone( &ssl->handshake->fin_sha256_psa, &sha256_psa );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash clone failed" ) );
return;
}
status = psa_hash_finish( &sha256_psa, hash, 32, &hash_size );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash finish failed" ) );
return;
}
*hlen = 32;
MBEDTLS_SSL_DEBUG_BUF( 3, "PSA calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= PSA calc verify" ) );
#else
mbedtls_sha256_context sha256;
mbedtls_sha256_init( &sha256 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc verify sha256" ) );
mbedtls_sha256_clone( &sha256, &ssl->handshake->fin_sha256 );
mbedtls_sha256_finish_ret( &sha256, hash );
*hlen = 32;
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_sha256_free( &sha256 );
#endif /* MBEDTLS_USE_PSA_CRYPTO */
return;
}
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
void ssl_calc_verify_tls_sha384( const mbedtls_ssl_context *ssl,
unsigned char hash[48],
size_t *hlen )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
size_t hash_size;
psa_status_t status;
psa_hash_operation_t sha384_psa = psa_hash_operation_init();
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> PSA calc verify sha384" ) );
status = psa_hash_clone( &ssl->handshake->fin_sha384_psa, &sha384_psa );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash clone failed" ) );
return;
}
status = psa_hash_finish( &sha384_psa, hash, 48, &hash_size );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash finish failed" ) );
return;
}
*hlen = 48;
MBEDTLS_SSL_DEBUG_BUF( 3, "PSA calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= PSA calc verify" ) );
#else
mbedtls_sha512_context sha512;
mbedtls_sha512_init( &sha512 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc verify sha384" ) );
mbedtls_sha512_clone( &sha512, &ssl->handshake->fin_sha512 );
mbedtls_sha512_finish_ret( &sha512, hash );
*hlen = 48;
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, *hlen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_sha512_free( &sha512 );
#endif /* MBEDTLS_USE_PSA_CRYPTO */
return;
}
#endif /* MBEDTLS_SHA512_C */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex )
{
unsigned char *p = ssl->handshake->premaster;
unsigned char *end = p + sizeof( ssl->handshake->premaster );
const unsigned char *psk = ssl->conf->psk;
size_t psk_len = ssl->conf->psk_len;
/* If the psk callback was called, use its result */
if( ssl->handshake->psk != NULL )
{
psk = ssl->handshake->psk;
psk_len = ssl->handshake->psk_len;
}
/*
* PMS = struct {
* opaque other_secret<0..2^16-1>;
* opaque psk<0..2^16-1>;
* };
* with "other_secret" depending on the particular key exchange
*/
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if( key_ex == MBEDTLS_KEY_EXCHANGE_PSK )
{
if( end - p < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( psk_len >> 8 );
*(p++) = (unsigned char)( psk_len );
if( end < p || (size_t)( end - p ) < psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memset( p, 0, psk_len );
p += psk_len;
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
if( key_ex == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
{
/*
* other_secret already set by the ClientKeyExchange message,
* and is 48 bytes long
*/
if( end - p < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
*p++ = 0;
*p++ = 48;
p += 48;
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
if( key_ex == MBEDTLS_KEY_EXCHANGE_DHE_PSK )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len;
/* Write length only when we know the actual value */
if( ( ret = mbedtls_dhm_calc_secret( &ssl->handshake->dhm_ctx,
p + 2, end - ( p + 2 ), &len,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_calc_secret", ret );
return( ret );
}
*(p++) = (unsigned char)( len >> 8 );
*(p++) = (unsigned char)( len );
p += len;
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( key_ex == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t zlen;
if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &zlen,
p + 2, end - ( p + 2 ),
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_calc_secret", ret );
return( ret );
}
*(p++) = (unsigned char)( zlen >> 8 );
*(p++) = (unsigned char)( zlen );
p += zlen;
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Z );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/* opaque psk<0..2^16-1>; */
if( end - p < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( psk_len >> 8 );
*(p++) = (unsigned char)( psk_len );
if( end < p || (size_t)( end - p ) < psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( p, psk, psk_len );
p += psk_len;
ssl->handshake->pmslen = p - ssl->handshake->premaster;
return( 0 );
}
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(MBEDTLS_SSL_PROTO_SSL3)
/*
* SSLv3.0 MAC functions
*/
#define SSL_MAC_MAX_BYTES 20 /* MD-5 or SHA-1 */
static void ssl_mac( mbedtls_md_context_t *md_ctx,
const unsigned char *secret,
const unsigned char *buf, size_t len,
const unsigned char *ctr, int type,
unsigned char out[SSL_MAC_MAX_BYTES] )
{
unsigned char header[11];
unsigned char padding[48];
int padlen;
int md_size = mbedtls_md_get_size( md_ctx->md_info );
int md_type = mbedtls_md_get_type( md_ctx->md_info );
/* Only MD5 and SHA-1 supported */
if( md_type == MBEDTLS_MD_MD5 )
padlen = 48;
else
padlen = 40;
memcpy( header, ctr, 8 );
header[ 8] = (unsigned char) type;
header[ 9] = (unsigned char)( len >> 8 );
header[10] = (unsigned char)( len );
memset( padding, 0x36, padlen );
mbedtls_md_starts( md_ctx );
mbedtls_md_update( md_ctx, secret, md_size );
mbedtls_md_update( md_ctx, padding, padlen );
mbedtls_md_update( md_ctx, header, 11 );
mbedtls_md_update( md_ctx, buf, len );
mbedtls_md_finish( md_ctx, out );
memset( padding, 0x5C, padlen );
mbedtls_md_starts( md_ctx );
mbedtls_md_update( md_ctx, secret, md_size );
mbedtls_md_update( md_ctx, padding, padlen );
mbedtls_md_update( md_ctx, out, md_size );
mbedtls_md_finish( md_ctx, out );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
/* The function below is only used in the Lucky 13 counter-measure in
* mbedtls_ssl_decrypt_buf(). These are the defines that guard the call site. */
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC) && \
( defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2) )
/* This function makes sure every byte in the memory region is accessed
* (in ascending addresses order) */
static void ssl_read_memory( unsigned char *p, size_t len )
{
unsigned char acc = 0;
volatile unsigned char force;
for( ; len != 0; p++, len-- )
acc ^= *p;
force = acc;
(void) force;
}
#endif /* SSL_SOME_MODES_USE_MAC && ( TLS1 || TLS1_1 || TLS1_2 ) */
/*
* Encryption/decryption functions
*/
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* This functions transforms a DTLS plaintext fragment and a record content
* type into an instance of the DTLSInnerPlaintext structure:
*
* struct {
* opaque content[DTLSPlaintext.length];
* ContentType real_type;
* uint8 zeros[length_of_padding];
* } DTLSInnerPlaintext;
*
* Input:
* - `content`: The beginning of the buffer holding the
* plaintext to be wrapped.
* - `*content_size`: The length of the plaintext in Bytes.
* - `max_len`: The number of Bytes available starting from
* `content`. This must be `>= *content_size`.
* - `rec_type`: The desired record content type.
*
* Output:
* - `content`: The beginning of the resulting DTLSInnerPlaintext structure.
* - `*content_size`: The length of the resulting DTLSInnerPlaintext structure.
*
* Returns:
* - `0` on success.
* - A negative error code if `max_len` didn't offer enough space
* for the expansion.
*/
static int ssl_cid_build_inner_plaintext( unsigned char *content,
size_t *content_size,
size_t remaining,
uint8_t rec_type )
{
size_t len = *content_size;
size_t pad = ( MBEDTLS_SSL_CID_PADDING_GRANULARITY -
( len + 1 ) % MBEDTLS_SSL_CID_PADDING_GRANULARITY ) %
MBEDTLS_SSL_CID_PADDING_GRANULARITY;
/* Write real content type */
if( remaining == 0 )
return( -1 );
content[ len ] = rec_type;
len++;
remaining--;
if( remaining < pad )
return( -1 );
memset( content + len, 0, pad );
len += pad;
remaining -= pad;
*content_size = len;
return( 0 );
}
/* This function parses a DTLSInnerPlaintext structure.
* See ssl_cid_build_inner_plaintext() for details. */
static int ssl_cid_parse_inner_plaintext( unsigned char const *content,
size_t *content_size,
uint8_t *rec_type )
{
size_t remaining = *content_size;
/* Determine length of padding by skipping zeroes from the back. */
do
{
if( remaining == 0 )
return( -1 );
remaining--;
} while( content[ remaining ] == 0 );
*content_size = remaining;
*rec_type = content[ remaining ];
return( 0 );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
/* `add_data` must have size 13 Bytes if the CID extension is disabled,
* and 13 + 1 + CID-length Bytes if the CID extension is enabled. */
static void ssl_extract_add_data_from_record( unsigned char* add_data,
size_t *add_data_len,
mbedtls_record *rec )
{
/* Quoting RFC 5246 (TLS 1.2):
*
* additional_data = seq_num + TLSCompressed.type +
* TLSCompressed.version + TLSCompressed.length;
*
* For the CID extension, this is extended as follows
* (quoting draft-ietf-tls-dtls-connection-id-05,
* https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05):
*
* additional_data = seq_num + DTLSPlaintext.type +
* DTLSPlaintext.version +
* cid +
* cid_length +
* length_of_DTLSInnerPlaintext;
*/
memcpy( add_data, rec->ctr, sizeof( rec->ctr ) );
add_data[8] = rec->type;
memcpy( add_data + 9, rec->ver, sizeof( rec->ver ) );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( rec->cid_len != 0 )
{
memcpy( add_data + 11, rec->cid, rec->cid_len );
add_data[11 + rec->cid_len + 0] = rec->cid_len;
add_data[11 + rec->cid_len + 1] = ( rec->data_len >> 8 ) & 0xFF;
add_data[11 + rec->cid_len + 2] = ( rec->data_len >> 0 ) & 0xFF;
*add_data_len = 13 + 1 + rec->cid_len;
}
else
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
{
add_data[11 + 0] = ( rec->data_len >> 8 ) & 0xFF;
add_data[11 + 1] = ( rec->data_len >> 0 ) & 0xFF;
*add_data_len = 13;
}
}
int mbedtls_ssl_encrypt_buf( mbedtls_ssl_context *ssl,
mbedtls_ssl_transform *transform,
mbedtls_record *rec,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
mbedtls_cipher_mode_t mode;
int auth_done = 0;
unsigned char * data;
unsigned char add_data[13 + 1 + MBEDTLS_SSL_CID_OUT_LEN_MAX ];
size_t add_data_len;
size_t post_avail;
/* The SSL context is only used for debugging purposes! */
#if !defined(MBEDTLS_DEBUG_C)
ssl = NULL; /* make sure we don't use it except for debug */
((void) ssl);
#endif
/* The PRNG is used for dynamic IV generation that's used
* for CBC transformations in TLS 1.1 and TLS 1.2. */
#if !( defined(MBEDTLS_CIPHER_MODE_CBC) && \
( defined(MBEDTLS_AES_C) || \
defined(MBEDTLS_ARIA_C) || \
defined(MBEDTLS_CAMELLIA_C) ) && \
( defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2) ) )
((void) f_rng);
((void) p_rng);
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> encrypt buf" ) );
if( transform == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no transform provided to encrypt_buf" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
if( rec == NULL
|| rec->buf == NULL
|| rec->buf_len < rec->data_offset
|| rec->buf_len - rec->data_offset < rec->data_len
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
|| rec->cid_len != 0
#endif
)
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad record structure provided to encrypt_buf" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
data = rec->buf + rec->data_offset;
post_avail = rec->buf_len - ( rec->data_len + rec->data_offset );
MBEDTLS_SSL_DEBUG_BUF( 4, "before encrypt: output payload",
data, rec->data_len );
mode = mbedtls_cipher_get_cipher_mode( &transform->cipher_ctx_enc );
if( rec->data_len > MBEDTLS_SSL_OUT_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Record content %u too large, maximum %d",
(unsigned) rec->data_len,
MBEDTLS_SSL_OUT_CONTENT_LEN ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/*
* Add CID information
*/
rec->cid_len = transform->out_cid_len;
memcpy( rec->cid, transform->out_cid, transform->out_cid_len );
MBEDTLS_SSL_DEBUG_BUF( 3, "CID", rec->cid, rec->cid_len );
if( rec->cid_len != 0 )
{
/*
* Wrap plaintext into DTLSInnerPlaintext structure.
* See ssl_cid_build_inner_plaintext() for more information.
*
* Note that this changes `rec->data_len`, and hence
* `post_avail` needs to be recalculated afterwards.
*/
if( ssl_cid_build_inner_plaintext( data,
&rec->data_len,
post_avail,
rec->type ) != 0 )
{
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
rec->type = MBEDTLS_SSL_MSG_CID;
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
post_avail = rec->buf_len - ( rec->data_len + rec->data_offset );
/*
* Add MAC before if needed
*/
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
if( mode == MBEDTLS_MODE_STREAM ||
( mode == MBEDTLS_MODE_CBC
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
&& transform->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED
#endif
) )
{
if( post_avail < transform->maclen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Buffer provided for encrypted record not large enough" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( transform->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
unsigned char mac[SSL_MAC_MAX_BYTES];
ssl_mac( &transform->md_ctx_enc, transform->mac_enc,
data, rec->data_len, rec->ctr, rec->type, mac );
memcpy( data + rec->data_len, mac, transform->maclen );
}
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( transform->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 )
{
unsigned char mac[MBEDTLS_SSL_MAC_ADD];
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
mbedtls_md_hmac_update( &transform->md_ctx_enc, add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_enc,
data, rec->data_len );
mbedtls_md_hmac_finish( &transform->md_ctx_enc, mac );
mbedtls_md_hmac_reset( &transform->md_ctx_enc );
memcpy( data + rec->data_len, mac, transform->maclen );
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "computed mac", data + rec->data_len,
transform->maclen );
rec->data_len += transform->maclen;
post_avail -= transform->maclen;
auth_done++;
}
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
/*
* Encrypt
*/
#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER)
if( mode == MBEDTLS_MODE_STREAM )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t olen;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of padding",
rec->data_len, 0 ) );
if( ( ret = mbedtls_cipher_crypt( &transform->cipher_ctx_enc,
transform->iv_enc, transform->ivlen,
data, rec->data_len,
data, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( rec->data_len != olen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* MBEDTLS_ARC4_C || MBEDTLS_CIPHER_NULL_CIPHER */
#if defined(MBEDTLS_GCM_C) || \
defined(MBEDTLS_CCM_C) || \
defined(MBEDTLS_CHACHAPOLY_C)
if( mode == MBEDTLS_MODE_GCM ||
mode == MBEDTLS_MODE_CCM ||
mode == MBEDTLS_MODE_CHACHAPOLY )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char iv[12];
size_t explicit_iv_len = transform->ivlen - transform->fixed_ivlen;
/* Check that there's space for both the authentication tag
* and the explicit IV before and after the record content. */
if( post_avail < transform->taglen ||
rec->data_offset < explicit_iv_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Buffer provided for encrypted record not large enough" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
/*
* Generate IV
*/
if( transform->ivlen == 12 && transform->fixed_ivlen == 4 )
{
/* GCM and CCM: fixed || explicit (=seqnum) */
memcpy( iv, transform->iv_enc, transform->fixed_ivlen );
memcpy( iv + transform->fixed_ivlen, rec->ctr,
explicit_iv_len );
/* Prefix record content with explicit IV. */
memcpy( data - explicit_iv_len, rec->ctr, explicit_iv_len );
}
else if( transform->ivlen == 12 && transform->fixed_ivlen == 12 )
{
/* ChachaPoly: fixed XOR sequence number */
unsigned char i;
memcpy( iv, transform->iv_enc, transform->fixed_ivlen );
for( i = 0; i < 8; i++ )
iv[i+4] ^= rec->ctr[i];
}
else
{
/* Reminder if we ever add an AEAD mode with a different size */
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (internal)",
iv, transform->ivlen );
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (transmitted)",
data - explicit_iv_len, explicit_iv_len );
MBEDTLS_SSL_DEBUG_BUF( 4, "additional data used for AEAD",
add_data, add_data_len );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including 0 bytes of padding",
rec->data_len ) );
/*
* Encrypt and authenticate
*/
if( ( ret = mbedtls_cipher_auth_encrypt( &transform->cipher_ctx_enc,
iv, transform->ivlen,
add_data, add_data_len, /* add data */
data, rec->data_len, /* source */
data, &rec->data_len, /* destination */
data + rec->data_len, transform->taglen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_auth_encrypt", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "after encrypt: tag",
data + rec->data_len, transform->taglen );
rec->data_len += transform->taglen + explicit_iv_len;
rec->data_offset -= explicit_iv_len;
post_avail -= transform->taglen;
auth_done++;
}
else
#endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */
#if defined(MBEDTLS_CIPHER_MODE_CBC) && \
( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) || defined(MBEDTLS_ARIA_C) )
if( mode == MBEDTLS_MODE_CBC )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t padlen, i;
size_t olen;
/* Currently we're always using minimal padding
* (up to 255 bytes would be allowed). */
padlen = transform->ivlen - ( rec->data_len + 1 ) % transform->ivlen;
if( padlen == transform->ivlen )
padlen = 0;
/* Check there's enough space in the buffer for the padding. */
if( post_avail < padlen + 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Buffer provided for encrypted record not large enough" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
for( i = 0; i <= padlen; i++ )
data[rec->data_len + i] = (unsigned char) padlen;
rec->data_len += padlen + 1;
post_avail -= padlen + 1;
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
/*
* Prepend per-record IV for block cipher in TLS v1.1 and up as per
* Method 1 (6.2.3.2. in RFC4346 and RFC5246)
*/
if( transform->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
if( f_rng == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "No PRNG provided to encrypt_record routine" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
if( rec->data_offset < transform->ivlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Buffer provided for encrypted record not large enough" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
/*
* Generate IV
*/
ret = f_rng( p_rng, transform->iv_enc, transform->ivlen );
if( ret != 0 )
return( ret );
memcpy( data - transform->ivlen, transform->iv_enc,
transform->ivlen );
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of IV and %d bytes of padding",
rec->data_len, transform->ivlen,
padlen + 1 ) );
if( ( ret = mbedtls_cipher_crypt( &transform->cipher_ctx_enc,
transform->iv_enc,
transform->ivlen,
data, rec->data_len,
data, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( rec->data_len != olen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1)
if( transform->minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 )
{
/*
* Save IV in SSL3 and TLS1
*/
memcpy( transform->iv_enc, transform->cipher_ctx_enc.iv,
transform->ivlen );
}
else
#endif
{
data -= transform->ivlen;
rec->data_offset -= transform->ivlen;
rec->data_len += transform->ivlen;
}
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if( auth_done == 0 )
{
unsigned char mac[MBEDTLS_SSL_MAC_ADD];
/*
* MAC(MAC_write_key, seq_num +
* TLSCipherText.type +
* TLSCipherText.version +
* length_of( (IV +) ENC(...) ) +
* IV + // except for TLS 1.0
* ENC(content + padding + padding_length));
*/
if( post_avail < transform->maclen)
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Buffer provided for encrypted record not large enough" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using encrypt then mac" ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "MAC'd meta-data", add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_enc, add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_enc,
data, rec->data_len );
mbedtls_md_hmac_finish( &transform->md_ctx_enc, mac );
mbedtls_md_hmac_reset( &transform->md_ctx_enc );
memcpy( data + rec->data_len, mac, transform->maclen );
rec->data_len += transform->maclen;
post_avail -= transform->maclen;
auth_done++;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
}
else
#endif /* MBEDTLS_CIPHER_MODE_CBC &&
( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C || MBEDTLS_ARIA_C ) */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/* Make extra sure authentication was performed, exactly once */
if( auth_done != 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= encrypt buf" ) );
return( 0 );
}
int mbedtls_ssl_decrypt_buf( mbedtls_ssl_context const *ssl,
mbedtls_ssl_transform *transform,
mbedtls_record *rec )
{
size_t olen;
mbedtls_cipher_mode_t mode;
int ret, auth_done = 0;
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
size_t padlen = 0, correct = 1;
#endif
unsigned char* data;
unsigned char add_data[13 + 1 + MBEDTLS_SSL_CID_IN_LEN_MAX ];
size_t add_data_len;
#if !defined(MBEDTLS_DEBUG_C)
ssl = NULL; /* make sure we don't use it except for debug */
((void) ssl);
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> decrypt buf" ) );
if( rec == NULL ||
rec->buf == NULL ||
rec->buf_len < rec->data_offset ||
rec->buf_len - rec->data_offset < rec->data_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad record structure provided to decrypt_buf" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
data = rec->buf + rec->data_offset;
mode = mbedtls_cipher_get_cipher_mode( &transform->cipher_ctx_dec );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/*
* Match record's CID with incoming CID.
*/
if( rec->cid_len != transform->in_cid_len ||
memcmp( rec->cid, transform->in_cid, rec->cid_len ) != 0 )
{
return( MBEDTLS_ERR_SSL_UNEXPECTED_CID );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER)
if( mode == MBEDTLS_MODE_STREAM )
{
padlen = 0;
if( ( ret = mbedtls_cipher_crypt( &transform->cipher_ctx_dec,
transform->iv_dec,
transform->ivlen,
data, rec->data_len,
data, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( rec->data_len != olen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* MBEDTLS_ARC4_C || MBEDTLS_CIPHER_NULL_CIPHER */
#if defined(MBEDTLS_GCM_C) || \
defined(MBEDTLS_CCM_C) || \
defined(MBEDTLS_CHACHAPOLY_C)
if( mode == MBEDTLS_MODE_GCM ||
mode == MBEDTLS_MODE_CCM ||
mode == MBEDTLS_MODE_CHACHAPOLY )
{
unsigned char iv[12];
size_t explicit_iv_len = transform->ivlen - transform->fixed_ivlen;
/*
* Prepare IV from explicit and implicit data.
*/
/* Check that there's enough space for the explicit IV
* (at the beginning of the record) and the MAC (at the
* end of the record). */
if( rec->data_len < explicit_iv_len + transform->taglen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < explicit_iv_len (%d) "
"+ taglen (%d)", rec->data_len,
explicit_iv_len, transform->taglen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
#if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CCM_C)
if( transform->ivlen == 12 && transform->fixed_ivlen == 4 )
{
/* GCM and CCM: fixed || explicit */
/* Fixed */
memcpy( iv, transform->iv_dec, transform->fixed_ivlen );
/* Explicit */
memcpy( iv + transform->fixed_ivlen, data, 8 );
}
else
#endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */
#if defined(MBEDTLS_CHACHAPOLY_C)
if( transform->ivlen == 12 && transform->fixed_ivlen == 12 )
{
/* ChachaPoly: fixed XOR sequence number */
unsigned char i;
memcpy( iv, transform->iv_dec, transform->fixed_ivlen );
for( i = 0; i < 8; i++ )
iv[i+4] ^= rec->ctr[i];
}
else
#endif /* MBEDTLS_CHACHAPOLY_C */
{
/* Reminder if we ever add an AEAD mode with a different size */
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/* Group changes to data, data_len, and add_data, because
* add_data depends on data_len. */
data += explicit_iv_len;
rec->data_offset += explicit_iv_len;
rec->data_len -= explicit_iv_len + transform->taglen;
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
MBEDTLS_SSL_DEBUG_BUF( 4, "additional data used for AEAD",
add_data, add_data_len );
/* Because of the check above, we know that there are
* explicit_iv_len Bytes preceeding data, and taglen
* bytes following data + data_len. This justifies
* the debug message and the invocation of
* mbedtls_cipher_auth_decrypt() below. */
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used", iv, transform->ivlen );
MBEDTLS_SSL_DEBUG_BUF( 4, "TAG used", data + rec->data_len,
transform->taglen );
/*
* Decrypt and authenticate
*/
if( ( ret = mbedtls_cipher_auth_decrypt( &transform->cipher_ctx_dec,
iv, transform->ivlen,
add_data, add_data_len,
data, rec->data_len,
data, &olen,
data + rec->data_len,
transform->taglen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_auth_decrypt", ret );
if( ret == MBEDTLS_ERR_CIPHER_AUTH_FAILED )
return( MBEDTLS_ERR_SSL_INVALID_MAC );
return( ret );
}
auth_done++;
/* Double-check that AEAD decryption doesn't change content length. */
if( olen != rec->data_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */
#if defined(MBEDTLS_CIPHER_MODE_CBC) && \
( defined(MBEDTLS_AES_C) || defined(MBEDTLS_CAMELLIA_C) || defined(MBEDTLS_ARIA_C) )
if( mode == MBEDTLS_MODE_CBC )
{
size_t minlen = 0;
/*
* Check immediate ciphertext sanity
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( transform->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
/* The ciphertext is prefixed with the CBC IV. */
minlen += transform->ivlen;
}
#endif
/* Size considerations:
*
* - The CBC cipher text must not be empty and hence
* at least of size transform->ivlen.
*
* Together with the potential IV-prefix, this explains
* the first of the two checks below.
*
* - The record must contain a MAC, either in plain or
* encrypted, depending on whether Encrypt-then-MAC
* is used or not.
* - If it is, the message contains the IV-prefix,
* the CBC ciphertext, and the MAC.
* - If it is not, the padded plaintext, and hence
* the CBC ciphertext, has at least length maclen + 1
* because there is at least the padding length byte.
*
* As the CBC ciphertext is not empty, both cases give the
* lower bound minlen + maclen + 1 on the record size, which
* we test for in the second check below.
*/
if( rec->data_len < minlen + transform->ivlen ||
rec->data_len < minlen + transform->maclen + 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < max( ivlen(%d), maclen (%d) "
"+ 1 ) ( + expl IV )", rec->data_len,
transform->ivlen,
transform->maclen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
/*
* Authenticate before decrypt if enabled
*/
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if( transform->encrypt_then_mac == MBEDTLS_SSL_ETM_ENABLED )
{
unsigned char mac_expect[MBEDTLS_SSL_MAC_ADD];
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using encrypt then mac" ) );
/* Update data_len in tandem with add_data.
*
* The subtraction is safe because of the previous check
* data_len >= minlen + maclen + 1.
*
* Afterwards, we know that data + data_len is followed by at
* least maclen Bytes, which justifies the call to
* mbedtls_ssl_safer_memcmp() below.
*
* Further, we still know that data_len > minlen */
rec->data_len -= transform->maclen;
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
/* Calculate expected MAC. */
MBEDTLS_SSL_DEBUG_BUF( 4, "MAC'd meta-data", add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_dec, add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_dec,
data, rec->data_len );
mbedtls_md_hmac_finish( &transform->md_ctx_dec, mac_expect );
mbedtls_md_hmac_reset( &transform->md_ctx_dec );
MBEDTLS_SSL_DEBUG_BUF( 4, "message mac", data + rec->data_len,
transform->maclen );
MBEDTLS_SSL_DEBUG_BUF( 4, "expected mac", mac_expect,
transform->maclen );
/* Compare expected MAC with MAC at the end of the record. */
if( mbedtls_ssl_safer_memcmp( data + rec->data_len, mac_expect,
transform->maclen ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "message mac does not match" ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
auth_done++;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
/*
* Check length sanity
*/
/* We know from above that data_len > minlen >= 0,
* so the following check in particular implies that
* data_len >= minlen + ivlen ( = minlen or 2 * minlen ). */
if( rec->data_len % transform->ivlen != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) %% ivlen (%d) != 0",
rec->data_len, transform->ivlen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
/*
* Initialize for prepended IV for block cipher in TLS v1.1 and up
*/
if( transform->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
/* Safe because data_len >= minlen + ivlen = 2 * ivlen. */
memcpy( transform->iv_dec, data, transform->ivlen );
data += transform->ivlen;
rec->data_offset += transform->ivlen;
rec->data_len -= transform->ivlen;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
/* We still have data_len % ivlen == 0 and data_len >= ivlen here. */
if( ( ret = mbedtls_cipher_crypt( &transform->cipher_ctx_dec,
transform->iv_dec, transform->ivlen,
data, rec->data_len, data, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
/* Double-check that length hasn't changed during decryption. */
if( rec->data_len != olen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1)
if( transform->minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 )
{
/*
* Save IV in SSL3 and TLS1, where CBC decryption of consecutive
* records is equivalent to CBC decryption of the concatenation
* of the records; in other words, IVs are maintained across
* record decryptions.
*/
memcpy( transform->iv_dec, transform->cipher_ctx_dec.iv,
transform->ivlen );
}
#endif
/* Safe since data_len >= minlen + maclen + 1, so after having
* subtracted at most minlen and maclen up to this point,
* data_len > 0 (because of data_len % ivlen == 0, it's actually
* >= ivlen ). */
padlen = data[rec->data_len - 1];
if( auth_done == 1 )
{
correct *= ( rec->data_len >= padlen + 1 );
padlen *= ( rec->data_len >= padlen + 1 );
}
else
{
#if defined(MBEDTLS_SSL_DEBUG_ALL)
if( rec->data_len < transform->maclen + padlen + 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < maclen (%d) + padlen (%d)",
rec->data_len,
transform->maclen,
padlen + 1 ) );
}
#endif
correct *= ( rec->data_len >= transform->maclen + padlen + 1 );
padlen *= ( rec->data_len >= transform->maclen + padlen + 1 );
}
padlen++;
/* Regardless of the validity of the padding,
* we have data_len >= padlen here. */
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( transform->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
if( padlen > transform->ivlen )
{
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad padding length: is %d, "
"should be no more than %d",
padlen, transform->ivlen ) );
#endif
correct = 0;
}
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( transform->minor_ver > MBEDTLS_SSL_MINOR_VERSION_0 )
{
/* The padding check involves a series of up to 256
* consecutive memory reads at the end of the record
* plaintext buffer. In order to hide the length and
* validity of the padding, always perform exactly
* `min(256,plaintext_len)` reads (but take into account
* only the last `padlen` bytes for the padding check). */
size_t pad_count = 0;
size_t real_count = 0;
volatile unsigned char* const check = data;
/* Index of first padding byte; it has been ensured above
* that the subtraction is safe. */
size_t const padding_idx = rec->data_len - padlen;
size_t const num_checks = rec->data_len <= 256 ? rec->data_len : 256;
size_t const start_idx = rec->data_len - num_checks;
size_t idx;
for( idx = start_idx; idx < rec->data_len; idx++ )
{
real_count |= ( idx >= padding_idx );
pad_count += real_count * ( check[idx] == padlen - 1 );
}
correct &= ( pad_count == padlen );
#if defined(MBEDTLS_SSL_DEBUG_ALL)
if( padlen > 0 && correct == 0 )
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad padding byte detected" ) );
#endif
padlen &= correct * 0x1FF;
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/* If the padding was found to be invalid, padlen == 0
* and the subtraction is safe. If the padding was found valid,
* padlen hasn't been changed and the previous assertion
* data_len >= padlen still holds. */
rec->data_len -= padlen;
}
else
#endif /* MBEDTLS_CIPHER_MODE_CBC &&
( MBEDTLS_AES_C || MBEDTLS_CAMELLIA_C || MBEDTLS_ARIA_C ) */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_BUF( 4, "raw buffer after decryption",
data, rec->data_len );
#endif
/*
* Authenticate if not done yet.
* Compute the MAC regardless of the padding result (RFC4346, CBCTIME).
*/
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
if( auth_done == 0 )
{
unsigned char mac_expect[MBEDTLS_SSL_MAC_ADD];
/* If the initial value of padlen was such that
* data_len < maclen + padlen + 1, then padlen
* got reset to 1, and the initial check
* data_len >= minlen + maclen + 1
* guarantees that at this point we still
* have at least data_len >= maclen.
*
* If the initial value of padlen was such that
* data_len >= maclen + padlen + 1, then we have
* subtracted either padlen + 1 (if the padding was correct)
* or 0 (if the padding was incorrect) since then,
* hence data_len >= maclen in any case.
*/
rec->data_len -= transform->maclen;
ssl_extract_add_data_from_record( add_data, &add_data_len, rec );
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( transform->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
ssl_mac( &transform->md_ctx_dec,
transform->mac_dec,
data, rec->data_len,
rec->ctr, rec->type,
mac_expect );
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( transform->minor_ver > MBEDTLS_SSL_MINOR_VERSION_0 )
{
/*
* Process MAC and always update for padlen afterwards to make
* total time independent of padlen.
*
* Known timing attacks:
* - Lucky Thirteen (http://www.isg.rhul.ac.uk/tls/TLStiming.pdf)
*
* To compensate for different timings for the MAC calculation
* depending on how much padding was removed (which is determined
* by padlen), process extra_run more blocks through the hash
* function.
*
* The formula in the paper is
* extra_run = ceil( (L1-55) / 64 ) - ceil( (L2-55) / 64 )
* where L1 is the size of the header plus the decrypted message
* plus CBC padding and L2 is the size of the header plus the
* decrypted message. This is for an underlying hash function
* with 64-byte blocks.
* We use ( (Lx+8) / 64 ) to handle 'negative Lx' values
* correctly. We round down instead of up, so -56 is the correct
* value for our calculations instead of -55.
*
* Repeat the formula rather than defining a block_size variable.
* This avoids requiring division by a variable at runtime
* (which would be marginally less efficient and would require
* linking an extra division function in some builds).
*/
size_t j, extra_run = 0;
unsigned char tmp[MBEDTLS_MD_MAX_BLOCK_SIZE];
/*
* The next two sizes are the minimum and maximum values of
* in_msglen over all padlen values.
*
* They're independent of padlen, since we previously did
* data_len -= padlen.
*
* Note that max_len + maclen is never more than the buffer
* length, as we previously did in_msglen -= maclen too.
*/
const size_t max_len = rec->data_len + padlen;
const size_t min_len = ( max_len > 256 ) ? max_len - 256 : 0;
memset( tmp, 0, sizeof( tmp ) );
switch( mbedtls_md_get_type( transform->md_ctx_dec.md_info ) )
{
#if defined(MBEDTLS_MD5_C) || defined(MBEDTLS_SHA1_C) || \
defined(MBEDTLS_SHA256_C)
case MBEDTLS_MD_MD5:
case MBEDTLS_MD_SHA1:
case MBEDTLS_MD_SHA256:
/* 8 bytes of message size, 64-byte compression blocks */
extra_run =
( add_data_len + rec->data_len + padlen + 8 ) / 64 -
( add_data_len + rec->data_len + 8 ) / 64;
break;
#endif
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_MD_SHA384:
/* 16 bytes of message size, 128-byte compression blocks */
extra_run =
( add_data_len + rec->data_len + padlen + 16 ) / 128 -
( add_data_len + rec->data_len + 16 ) / 128;
break;
#endif
default:
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
extra_run &= correct * 0xFF;
mbedtls_md_hmac_update( &transform->md_ctx_dec, add_data,
add_data_len );
mbedtls_md_hmac_update( &transform->md_ctx_dec, data,
rec->data_len );
/* Make sure we access everything even when padlen > 0. This
* makes the synchronisation requirements for just-in-time
* Prime+Probe attacks much tighter and hopefully impractical. */
ssl_read_memory( data + rec->data_len, padlen );
mbedtls_md_hmac_finish( &transform->md_ctx_dec, mac_expect );
/* Call mbedtls_md_process at least once due to cache attacks
* that observe whether md_process() was called of not */
for( j = 0; j < extra_run + 1; j++ )
mbedtls_md_process( &transform->md_ctx_dec, tmp );
mbedtls_md_hmac_reset( &transform->md_ctx_dec );
/* Make sure we access all the memory that could contain the MAC,
* before we check it in the next code block. This makes the
* synchronisation requirements for just-in-time Prime+Probe
* attacks much tighter and hopefully impractical. */
ssl_read_memory( data + min_len,
max_len - min_len + transform->maclen );
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_BUF( 4, "expected mac", mac_expect, transform->maclen );
MBEDTLS_SSL_DEBUG_BUF( 4, "message mac", data + rec->data_len, transform->maclen );
#endif
if( mbedtls_ssl_safer_memcmp( data + rec->data_len, mac_expect,
transform->maclen ) != 0 )
{
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_MSG( 1, ( "message mac does not match" ) );
#endif
correct = 0;
}
auth_done++;
}
/*
* Finally check the correct flag
*/
if( correct == 0 )
return( MBEDTLS_ERR_SSL_INVALID_MAC );
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
/* Make extra sure authentication was performed, exactly once */
if( auth_done != 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( rec->cid_len != 0 )
{
ret = ssl_cid_parse_inner_plaintext( data, &rec->data_len,
&rec->type );
if( ret != 0 )
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= decrypt buf" ) );
return( 0 );
}
#undef MAC_NONE
#undef MAC_PLAINTEXT
#undef MAC_CIPHERTEXT
#if defined(MBEDTLS_ZLIB_SUPPORT)
/*
* Compression/decompression functions
*/
static int ssl_compress_buf( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *msg_post = ssl->out_msg;
ptrdiff_t bytes_written = ssl->out_msg - ssl->out_buf;
size_t len_pre = ssl->out_msglen;
unsigned char *msg_pre = ssl->compress_buf;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> compress buf" ) );
if( len_pre == 0 )
return( 0 );
memcpy( msg_pre, ssl->out_msg, len_pre );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before compression: msglen = %d, ",
ssl->out_msglen ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "before compression: output payload",
ssl->out_msg, ssl->out_msglen );
ssl->transform_out->ctx_deflate.next_in = msg_pre;
ssl->transform_out->ctx_deflate.avail_in = len_pre;
ssl->transform_out->ctx_deflate.next_out = msg_post;
ssl->transform_out->ctx_deflate.avail_out = MBEDTLS_SSL_OUT_BUFFER_LEN - bytes_written;
ret = deflate( &ssl->transform_out->ctx_deflate, Z_SYNC_FLUSH );
if( ret != Z_OK )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "failed to perform compression (%d)", ret ) );
return( MBEDTLS_ERR_SSL_COMPRESSION_FAILED );
}
ssl->out_msglen = MBEDTLS_SSL_OUT_BUFFER_LEN -
ssl->transform_out->ctx_deflate.avail_out - bytes_written;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "after compression: msglen = %d, ",
ssl->out_msglen ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "after compression: output payload",
ssl->out_msg, ssl->out_msglen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= compress buf" ) );
return( 0 );
}
static int ssl_decompress_buf( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *msg_post = ssl->in_msg;
ptrdiff_t header_bytes = ssl->in_msg - ssl->in_buf;
size_t len_pre = ssl->in_msglen;
unsigned char *msg_pre = ssl->compress_buf;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> decompress buf" ) );
if( len_pre == 0 )
return( 0 );
memcpy( msg_pre, ssl->in_msg, len_pre );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before decompression: msglen = %d, ",
ssl->in_msglen ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "before decompression: input payload",
ssl->in_msg, ssl->in_msglen );
ssl->transform_in->ctx_inflate.next_in = msg_pre;
ssl->transform_in->ctx_inflate.avail_in = len_pre;
ssl->transform_in->ctx_inflate.next_out = msg_post;
ssl->transform_in->ctx_inflate.avail_out = MBEDTLS_SSL_IN_BUFFER_LEN -
header_bytes;
ret = inflate( &ssl->transform_in->ctx_inflate, Z_SYNC_FLUSH );
if( ret != Z_OK )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "failed to perform decompression (%d)", ret ) );
return( MBEDTLS_ERR_SSL_COMPRESSION_FAILED );
}
ssl->in_msglen = MBEDTLS_SSL_IN_BUFFER_LEN -
ssl->transform_in->ctx_inflate.avail_out - header_bytes;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "after decompression: msglen = %d, ",
ssl->in_msglen ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "after decompression: input payload",
ssl->in_msg, ssl->in_msglen );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= decompress buf" ) );
return( 0 );
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_RENEGOTIATION)
static int ssl_write_hello_request( mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static int ssl_resend_hello_request( mbedtls_ssl_context *ssl )
{
/* If renegotiation is not enforced, retransmit until we would reach max
* timeout if we were using the usual handshake doubling scheme */
if( ssl->conf->renego_max_records < 0 )
{
uint32_t ratio = ssl->conf->hs_timeout_max / ssl->conf->hs_timeout_min + 1;
unsigned char doublings = 1;
while( ratio != 0 )
{
++doublings;
ratio >>= 1;
}
if( ++ssl->renego_records_seen > doublings )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "no longer retransmitting hello request" ) );
return( 0 );
}
}
return( ssl_write_hello_request( ssl ) );
}
#endif
#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_RENEGOTIATION */
/*
* Fill the input message buffer by appending data to it.
* The amount of data already fetched is in ssl->in_left.
*
* If we return 0, is it guaranteed that (at least) nb_want bytes are
* available (from this read and/or a previous one). Otherwise, an error code
* is returned (possibly EOF or WANT_READ).
*
* With stream transport (TLS) on success ssl->in_left == nb_want, but
* with datagram transport (DTLS) on success ssl->in_left >= nb_want,
* since we always read a whole datagram at once.
*
* For DTLS, it is up to the caller to set ssl->next_record_offset when
* they're done reading a record.
*/
int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> fetch input" ) );
if( ssl->f_recv == NULL && ssl->f_recv_timeout == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Bad usage of mbedtls_ssl_set_bio() "
"or mbedtls_ssl_set_bio()" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
if( nb_want > MBEDTLS_SSL_IN_BUFFER_LEN - (size_t)( ssl->in_hdr - ssl->in_buf ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "requesting more data than fits" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
uint32_t timeout;
/* Just to be sure */
if( ssl->f_set_timer == NULL || ssl->f_get_timer == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "You must use "
"mbedtls_ssl_set_timer_cb() for DTLS" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/*
* The point is, we need to always read a full datagram at once, so we
* sometimes read more then requested, and handle the additional data.
* It could be the rest of the current record (while fetching the
* header) and/or some other records in the same datagram.
*/
/*
* Move to the next record in the already read datagram if applicable
*/
if( ssl->next_record_offset != 0 )
{
if( ssl->in_left < ssl->next_record_offset )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl->in_left -= ssl->next_record_offset;
if( ssl->in_left != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "next record in same datagram, offset: %d",
ssl->next_record_offset ) );
memmove( ssl->in_hdr,
ssl->in_hdr + ssl->next_record_offset,
ssl->in_left );
}
ssl->next_record_offset = 0;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
/*
* Done if we already have enough data.
*/
if( nb_want <= ssl->in_left)
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= fetch input" ) );
return( 0 );
}
/*
* A record can't be split across datagrams. If we need to read but
* are not at the beginning of a new record, the caller did something
* wrong.
*/
if( ssl->in_left != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* Don't even try to read if time's out already.
* This avoids by-passing the timer when repeatedly receiving messages
* that will end up being dropped.
*/
if( ssl_check_timer( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "timer has expired" ) );
ret = MBEDTLS_ERR_SSL_TIMEOUT;
}
else
{
len = MBEDTLS_SSL_IN_BUFFER_LEN - ( ssl->in_hdr - ssl->in_buf );
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
timeout = ssl->handshake->retransmit_timeout;
else
timeout = ssl->conf->read_timeout;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "f_recv_timeout: %u ms", timeout ) );
if( ssl->f_recv_timeout != NULL )
ret = ssl->f_recv_timeout( ssl->p_bio, ssl->in_hdr, len,
timeout );
else
ret = ssl->f_recv( ssl->p_bio, ssl->in_hdr, len );
MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_recv(_timeout)", ret );
if( ret == 0 )
return( MBEDTLS_ERR_SSL_CONN_EOF );
}
if( ret == MBEDTLS_ERR_SSL_TIMEOUT )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "timeout" ) );
ssl_set_timer( ssl, 0 );
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
if( ssl_double_retransmit_timeout( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "handshake timeout" ) );
return( MBEDTLS_ERR_SSL_TIMEOUT );
}
if( ( ret = mbedtls_ssl_resend( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_resend", ret );
return( ret );
}
return( MBEDTLS_ERR_SSL_WANT_READ );
}
#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_RENEGOTIATION)
else if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING )
{
if( ( ret = ssl_resend_hello_request( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_resend_hello_request", ret );
return( ret );
}
return( MBEDTLS_ERR_SSL_WANT_READ );
}
#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_RENEGOTIATION */
}
if( ret < 0 )
return( ret );
ssl->in_left = ret;
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
while( ssl->in_left < nb_want )
{
len = nb_want - ssl->in_left;
if( ssl_check_timer( ssl ) != 0 )
ret = MBEDTLS_ERR_SSL_TIMEOUT;
else
{
if( ssl->f_recv_timeout != NULL )
{
ret = ssl->f_recv_timeout( ssl->p_bio,
ssl->in_hdr + ssl->in_left, len,
ssl->conf->read_timeout );
}
else
{
ret = ssl->f_recv( ssl->p_bio,
ssl->in_hdr + ssl->in_left, len );
}
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_recv(_timeout)", ret );
if( ret == 0 )
return( MBEDTLS_ERR_SSL_CONN_EOF );
if( ret < 0 )
return( ret );
if ( (size_t)ret > len || ( INT_MAX > SIZE_MAX && ret > SIZE_MAX ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1,
( "f_recv returned %d bytes but only %lu were requested",
ret, (unsigned long)len ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl->in_left += ret;
}
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= fetch input" ) );
return( 0 );
}
/*
* Flush any data not yet written
*/
int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *buf;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> flush output" ) );
if( ssl->f_send == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Bad usage of mbedtls_ssl_set_bio() "
"or mbedtls_ssl_set_bio()" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Avoid incrementing counter if data is flushed */
if( ssl->out_left == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= flush output" ) );
return( 0 );
}
while( ssl->out_left > 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "message length: %d, out_left: %d",
mbedtls_ssl_out_hdr_len( ssl ) + ssl->out_msglen, ssl->out_left ) );
buf = ssl->out_hdr - ssl->out_left;
ret = ssl->f_send( ssl->p_bio, buf, ssl->out_left );
MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_send", ret );
if( ret <= 0 )
return( ret );
if( (size_t)ret > ssl->out_left || ( INT_MAX > SIZE_MAX && ret > SIZE_MAX ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1,
( "f_send returned %d bytes but only %lu bytes were sent",
ret, (unsigned long)ssl->out_left ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl->out_left -= ret;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->out_hdr = ssl->out_buf;
}
else
#endif
{
ssl->out_hdr = ssl->out_buf + 8;
}
ssl_update_out_pointers( ssl, ssl->transform_out );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= flush output" ) );
return( 0 );
}
/*
* Functions to handle the DTLS retransmission state machine
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/*
* Append current handshake message to current outgoing flight
*/
static int ssl_flight_append( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_flight_item *msg;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> ssl_flight_append" ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "message appended to flight",
ssl->out_msg, ssl->out_msglen );
/* Allocate space for current message */
if( ( msg = mbedtls_calloc( 1, sizeof( mbedtls_ssl_flight_item ) ) ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc %d bytes failed",
sizeof( mbedtls_ssl_flight_item ) ) );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
if( ( msg->p = mbedtls_calloc( 1, ssl->out_msglen ) ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc %d bytes failed", ssl->out_msglen ) );
mbedtls_free( msg );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
/* Copy current handshake message with headers */
memcpy( msg->p, ssl->out_msg, ssl->out_msglen );
msg->len = ssl->out_msglen;
msg->type = ssl->out_msgtype;
msg->next = NULL;
/* Append to the current flight */
if( ssl->handshake->flight == NULL )
ssl->handshake->flight = msg;
else
{
mbedtls_ssl_flight_item *cur = ssl->handshake->flight;
while( cur->next != NULL )
cur = cur->next;
cur->next = msg;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= ssl_flight_append" ) );
return( 0 );
}
/*
* Free the current flight of handshake messages
*/
static void ssl_flight_free( mbedtls_ssl_flight_item *flight )
{
mbedtls_ssl_flight_item *cur = flight;
mbedtls_ssl_flight_item *next;
while( cur != NULL )
{
next = cur->next;
mbedtls_free( cur->p );
mbedtls_free( cur );
cur = next;
}
}
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
static void ssl_dtls_replay_reset( mbedtls_ssl_context *ssl );
#endif
/*
* Swap transform_out and out_ctr with the alternative ones
*/
static void ssl_swap_epochs( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_transform *tmp_transform;
unsigned char tmp_out_ctr[8];
if( ssl->transform_out == ssl->handshake->alt_transform_out )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip swap epochs" ) );
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "swap epochs" ) );
/* Swap transforms */
tmp_transform = ssl->transform_out;
ssl->transform_out = ssl->handshake->alt_transform_out;
ssl->handshake->alt_transform_out = tmp_transform;
/* Swap epoch + sequence_number */
memcpy( tmp_out_ctr, ssl->cur_out_ctr, 8 );
memcpy( ssl->cur_out_ctr, ssl->handshake->alt_out_ctr, 8 );
memcpy( ssl->handshake->alt_out_ctr, tmp_out_ctr, 8 );
/* Adjust to the newly activated transform */
ssl_update_out_pointers( ssl, ssl->transform_out );
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_activate != NULL )
{
if( ( ret = mbedtls_ssl_hw_record_activate( ssl, MBEDTLS_SSL_CHANNEL_OUTBOUND ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_activate", ret );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
}
/*
* Retransmit the current flight of messages.
*/
int mbedtls_ssl_resend( mbedtls_ssl_context *ssl )
{
int ret = 0;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> mbedtls_ssl_resend" ) );
ret = mbedtls_ssl_flight_transmit( ssl );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= mbedtls_ssl_resend" ) );
return( ret );
}
/*
* Transmit or retransmit the current flight of messages.
*
* Need to remember the current message in case flush_output returns
* WANT_WRITE, causing us to exit this function and come back later.
* This function must be called until state is no longer SENDING.
*/
int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> mbedtls_ssl_flight_transmit" ) );
if( ssl->handshake->retransmit_state != MBEDTLS_SSL_RETRANS_SENDING )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "initialise flight transmission" ) );
ssl->handshake->cur_msg = ssl->handshake->flight;
ssl->handshake->cur_msg_p = ssl->handshake->flight->p + 12;
ssl_swap_epochs( ssl );
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_SENDING;
}
while( ssl->handshake->cur_msg != NULL )
{
size_t max_frag_len;
const mbedtls_ssl_flight_item * const cur = ssl->handshake->cur_msg;
int const is_finished =
( cur->type == MBEDTLS_SSL_MSG_HANDSHAKE &&
cur->p[0] == MBEDTLS_SSL_HS_FINISHED );
uint8_t const force_flush = ssl->disable_datagram_packing == 1 ?
SSL_FORCE_FLUSH : SSL_DONT_FORCE_FLUSH;
/* Swap epochs before sending Finished: we can't do it after
* sending ChangeCipherSpec, in case write returns WANT_READ.
* Must be done before copying, may change out_msg pointer */
if( is_finished && ssl->handshake->cur_msg_p == ( cur->p + 12 ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "swap epochs to send finished message" ) );
ssl_swap_epochs( ssl );
}
ret = ssl_get_remaining_payload_in_datagram( ssl );
if( ret < 0 )
return( ret );
max_frag_len = (size_t) ret;
/* CCS is copied as is, while HS messages may need fragmentation */
if( cur->type == MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC )
{
if( max_frag_len == 0 )
{
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
return( ret );
continue;
}
memcpy( ssl->out_msg, cur->p, cur->len );
ssl->out_msglen = cur->len;
ssl->out_msgtype = cur->type;
/* Update position inside current message */
ssl->handshake->cur_msg_p += cur->len;
}
else
{
const unsigned char * const p = ssl->handshake->cur_msg_p;
const size_t hs_len = cur->len - 12;
const size_t frag_off = p - ( cur->p + 12 );
const size_t rem_len = hs_len - frag_off;
size_t cur_hs_frag_len, max_hs_frag_len;
if( ( max_frag_len < 12 ) || ( max_frag_len == 12 && hs_len != 0 ) )
{
if( is_finished )
ssl_swap_epochs( ssl );
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
return( ret );
continue;
}
max_hs_frag_len = max_frag_len - 12;
cur_hs_frag_len = rem_len > max_hs_frag_len ?
max_hs_frag_len : rem_len;
if( frag_off == 0 && cur_hs_frag_len != hs_len )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "fragmenting handshake message (%u > %u)",
(unsigned) cur_hs_frag_len,
(unsigned) max_hs_frag_len ) );
}
/* Messages are stored with handshake headers as if not fragmented,
* copy beginning of headers then fill fragmentation fields.
* Handshake headers: type(1) len(3) seq(2) f_off(3) f_len(3) */
memcpy( ssl->out_msg, cur->p, 6 );
ssl->out_msg[6] = ( ( frag_off >> 16 ) & 0xff );
ssl->out_msg[7] = ( ( frag_off >> 8 ) & 0xff );
ssl->out_msg[8] = ( ( frag_off ) & 0xff );
ssl->out_msg[ 9] = ( ( cur_hs_frag_len >> 16 ) & 0xff );
ssl->out_msg[10] = ( ( cur_hs_frag_len >> 8 ) & 0xff );
ssl->out_msg[11] = ( ( cur_hs_frag_len ) & 0xff );
MBEDTLS_SSL_DEBUG_BUF( 3, "handshake header", ssl->out_msg, 12 );
/* Copy the handshake message content and set records fields */
memcpy( ssl->out_msg + 12, p, cur_hs_frag_len );
ssl->out_msglen = cur_hs_frag_len + 12;
ssl->out_msgtype = cur->type;
/* Update position inside current message */
ssl->handshake->cur_msg_p += cur_hs_frag_len;
}
/* If done with the current message move to the next one if any */
if( ssl->handshake->cur_msg_p >= cur->p + cur->len )
{
if( cur->next != NULL )
{
ssl->handshake->cur_msg = cur->next;
ssl->handshake->cur_msg_p = cur->next->p + 12;
}
else
{
ssl->handshake->cur_msg = NULL;
ssl->handshake->cur_msg_p = NULL;
}
}
/* Actually send the message out */
if( ( ret = mbedtls_ssl_write_record( ssl, force_flush ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
}
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
return( ret );
/* Update state and set timer */
if( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER )
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_FINISHED;
else
{
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_WAITING;
ssl_set_timer( ssl, ssl->handshake->retransmit_timeout );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= mbedtls_ssl_flight_transmit" ) );
return( 0 );
}
/*
* To be called when the last message of an incoming flight is received.
*/
void mbedtls_ssl_recv_flight_completed( mbedtls_ssl_context *ssl )
{
/* We won't need to resend that one any more */
ssl_flight_free( ssl->handshake->flight );
ssl->handshake->flight = NULL;
ssl->handshake->cur_msg = NULL;
/* The next incoming flight will start with this msg_seq */
ssl->handshake->in_flight_start_seq = ssl->handshake->in_msg_seq;
/* We don't want to remember CCS's across flight boundaries. */
ssl->handshake->buffering.seen_ccs = 0;
/* Clear future message buffering structure. */
ssl_buffering_free( ssl );
/* Cancel timer */
ssl_set_timer( ssl, 0 );
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == MBEDTLS_SSL_HS_FINISHED )
{
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_FINISHED;
}
else
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_PREPARING;
}
/*
* To be called when the last message of an outgoing flight is send.
*/
void mbedtls_ssl_send_flight_completed( mbedtls_ssl_context *ssl )
{
ssl_reset_retransmit_timeout( ssl );
ssl_set_timer( ssl, ssl->handshake->retransmit_timeout );
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == MBEDTLS_SSL_HS_FINISHED )
{
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_FINISHED;
}
else
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_WAITING;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/*
* Handshake layer functions
*/
/*
* Write (DTLS: or queue) current handshake (including CCS) message.
*
* - fill in handshake headers
* - update handshake checksum
* - DTLS: save message for resending
* - then pass to the record layer
*
* DTLS: except for HelloRequest, messages are only queued, and will only be
* actually sent when calling flight_transmit() or resend().
*
* Inputs:
* - ssl->out_msglen: 4 + actual handshake message len
* (4 is the size of handshake headers for TLS)
* - ssl->out_msg[0]: the handshake type (ClientHello, ServerHello, etc)
* - ssl->out_msg + 4: the handshake message body
*
* Outputs, ie state before passing to flight_append() or write_record():
* - ssl->out_msglen: the length of the record contents
* (including handshake headers but excluding record headers)
* - ssl->out_msg: the record contents (handshake headers + content)
*/
int mbedtls_ssl_write_handshake_msg( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
const size_t hs_len = ssl->out_msglen - 4;
const unsigned char hs_type = ssl->out_msg[0];
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write handshake message" ) );
/*
* Sanity checks
*/
if( ssl->out_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->out_msgtype != MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC )
{
/* In SSLv3, the client might send a NoCertificate alert. */
#if defined(MBEDTLS_SSL_PROTO_SSL3) && defined(MBEDTLS_SSL_CLI_C)
if( ! ( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 &&
ssl->out_msgtype == MBEDTLS_SSL_MSG_ALERT &&
ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT ) )
#endif /* MBEDTLS_SSL_PROTO_SSL3 && MBEDTLS_SSL_SRV_C */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
/* Whenever we send anything different from a
* HelloRequest we should be in a handshake - double check. */
if( ! ( ssl->out_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
hs_type == MBEDTLS_SSL_HS_HELLO_REQUEST ) &&
ssl->handshake == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL &&
ssl->handshake->retransmit_state == MBEDTLS_SSL_RETRANS_SENDING )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#endif
/* Double-check that we did not exceed the bounds
* of the outgoing record buffer.
* This should never fail as the various message
* writing functions must obey the bounds of the
* outgoing record buffer, but better be safe.
*
* Note: We deliberately do not check for the MTU or MFL here.
*/
if( ssl->out_msglen > MBEDTLS_SSL_OUT_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Record too large: "
"size %u, maximum %u",
(unsigned) ssl->out_msglen,
(unsigned) MBEDTLS_SSL_OUT_CONTENT_LEN ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* Fill handshake headers
*/
if( ssl->out_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE )
{
ssl->out_msg[1] = (unsigned char)( hs_len >> 16 );
ssl->out_msg[2] = (unsigned char)( hs_len >> 8 );
ssl->out_msg[3] = (unsigned char)( hs_len );
/*
* DTLS has additional fields in the Handshake layer,
* between the length field and the actual payload:
* uint16 message_seq;
* uint24 fragment_offset;
* uint24 fragment_length;
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Make room for the additional DTLS fields */
if( MBEDTLS_SSL_OUT_CONTENT_LEN - ssl->out_msglen < 8 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "DTLS handshake message too large: "
"size %u, maximum %u",
(unsigned) ( hs_len ),
(unsigned) ( MBEDTLS_SSL_OUT_CONTENT_LEN - 12 ) ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
memmove( ssl->out_msg + 12, ssl->out_msg + 4, hs_len );
ssl->out_msglen += 8;
/* Write message_seq and update it, except for HelloRequest */
if( hs_type != MBEDTLS_SSL_HS_HELLO_REQUEST )
{
ssl->out_msg[4] = ( ssl->handshake->out_msg_seq >> 8 ) & 0xFF;
ssl->out_msg[5] = ( ssl->handshake->out_msg_seq ) & 0xFF;
++( ssl->handshake->out_msg_seq );
}
else
{
ssl->out_msg[4] = 0;
ssl->out_msg[5] = 0;
}
/* Handshake hashes are computed without fragmentation,
* so set frag_offset = 0 and frag_len = hs_len for now */
memset( ssl->out_msg + 6, 0x00, 3 );
memcpy( ssl->out_msg + 9, ssl->out_msg + 1, 3 );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* Update running hashes of handshake messages seen */
if( hs_type != MBEDTLS_SSL_HS_HELLO_REQUEST )
ssl->handshake->update_checksum( ssl, ssl->out_msg, ssl->out_msglen );
}
/* Either send now, or just save to be sent (and resent) later */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
! ( ssl->out_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
hs_type == MBEDTLS_SSL_HS_HELLO_REQUEST ) )
{
if( ( ret = ssl_flight_append( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_flight_append", ret );
return( ret );
}
}
else
#endif
{
if( ( ret = mbedtls_ssl_write_record( ssl, SSL_FORCE_FLUSH ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write handshake message" ) );
return( 0 );
}
/*
* Record layer functions
*/
/*
* Write current record.
*
* Uses:
* - ssl->out_msgtype: type of the message (AppData, Handshake, Alert, CCS)
* - ssl->out_msglen: length of the record content (excl headers)
* - ssl->out_msg: record content
*/
int mbedtls_ssl_write_record( mbedtls_ssl_context *ssl, uint8_t force_flush )
{
int ret, done = 0;
size_t len = ssl->out_msglen;
uint8_t flush = force_flush;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write record" ) );
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( ssl->transform_out != NULL &&
ssl->session_out->compression == MBEDTLS_SSL_COMPRESS_DEFLATE )
{
if( ( ret = ssl_compress_buf( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_compress_buf", ret );
return( ret );
}
len = ssl->out_msglen;
}
#endif /*MBEDTLS_ZLIB_SUPPORT */
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_write != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_write()" ) );
ret = mbedtls_ssl_hw_record_write( ssl );
if( ret != 0 && ret != MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_write", ret );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
if( ret == 0 )
done = 1;
}
#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
if( !done )
{
unsigned i;
size_t protected_record_size;
/* Skip writing the record content type to after the encryption,
* as it may change when using the CID extension. */
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->conf->transport, ssl->out_hdr + 1 );
memcpy( ssl->out_ctr, ssl->cur_out_ctr, 8 );
ssl->out_len[0] = (unsigned char)( len >> 8 );
ssl->out_len[1] = (unsigned char)( len );
if( ssl->transform_out != NULL )
{
mbedtls_record rec;
rec.buf = ssl->out_iv;
rec.buf_len = MBEDTLS_SSL_OUT_BUFFER_LEN -
( ssl->out_iv - ssl->out_buf );
rec.data_len = ssl->out_msglen;
rec.data_offset = ssl->out_msg - rec.buf;
memcpy( &rec.ctr[0], ssl->out_ctr, 8 );
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->conf->transport, rec.ver );
rec.type = ssl->out_msgtype;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* The CID is set by mbedtls_ssl_encrypt_buf(). */
rec.cid_len = 0;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
if( ( ret = mbedtls_ssl_encrypt_buf( ssl, ssl->transform_out, &rec,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_encrypt_buf", ret );
return( ret );
}
if( rec.data_offset != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/* Update the record content type and CID. */
ssl->out_msgtype = rec.type;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID )
memcpy( ssl->out_cid, rec.cid, rec.cid_len );
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->out_msglen = len = rec.data_len;
ssl->out_len[0] = (unsigned char)( rec.data_len >> 8 );
ssl->out_len[1] = (unsigned char)( rec.data_len );
}
protected_record_size = len + mbedtls_ssl_out_hdr_len( ssl );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/* In case of DTLS, double-check that we don't exceed
* the remaining space in the datagram. */
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ret = ssl_get_remaining_space_in_datagram( ssl );
if( ret < 0 )
return( ret );
if( protected_record_size > (size_t) ret )
{
/* Should never happen */
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* Now write the potentially updated record content type. */
ssl->out_hdr[0] = (unsigned char) ssl->out_msgtype;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "output record: msgtype = %d, "
"version = [%d:%d], msglen = %d",
ssl->out_hdr[0], ssl->out_hdr[1],
ssl->out_hdr[2], len ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "output record sent to network",
ssl->out_hdr, protected_record_size );
ssl->out_left += protected_record_size;
ssl->out_hdr += protected_record_size;
ssl_update_out_pointers( ssl, ssl->transform_out );
for( i = 8; i > ssl_ep_len( ssl ); i-- )
if( ++ssl->cur_out_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == ssl_ep_len( ssl ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "outgoing message counter would wrap" ) );
return( MBEDTLS_ERR_SSL_COUNTER_WRAPPING );
}
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
flush == SSL_DONT_FORCE_FLUSH )
{
size_t remaining;
ret = ssl_get_remaining_payload_in_datagram( ssl );
if( ret < 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_get_remaining_payload_in_datagram",
ret );
return( ret );
}
remaining = (size_t) ret;
if( remaining == 0 )
{
flush = SSL_FORCE_FLUSH;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Still %u bytes available in current datagram", (unsigned) remaining ) );
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
if( ( flush == SSL_FORCE_FLUSH ) &&
( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flush_output", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write record" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static int ssl_hs_is_proper_fragment( mbedtls_ssl_context *ssl )
{
if( ssl->in_msglen < ssl->in_hslen ||
memcmp( ssl->in_msg + 6, "\0\0\0", 3 ) != 0 ||
memcmp( ssl->in_msg + 9, ssl->in_msg + 1, 3 ) != 0 )
{
return( 1 );
}
return( 0 );
}
static uint32_t ssl_get_hs_frag_len( mbedtls_ssl_context const *ssl )
{
return( ( ssl->in_msg[9] << 16 ) |
( ssl->in_msg[10] << 8 ) |
ssl->in_msg[11] );
}
static uint32_t ssl_get_hs_frag_off( mbedtls_ssl_context const *ssl )
{
return( ( ssl->in_msg[6] << 16 ) |
( ssl->in_msg[7] << 8 ) |
ssl->in_msg[8] );
}
static int ssl_check_hs_header( mbedtls_ssl_context const *ssl )
{
uint32_t msg_len, frag_off, frag_len;
msg_len = ssl_get_hs_total_len( ssl );
frag_off = ssl_get_hs_frag_off( ssl );
frag_len = ssl_get_hs_frag_len( ssl );
if( frag_off > msg_len )
return( -1 );
if( frag_len > msg_len - frag_off )
return( -1 );
if( frag_len + 12 > ssl->in_msglen )
return( -1 );
return( 0 );
}
/*
* Mark bits in bitmask (used for DTLS HS reassembly)
*/
static void ssl_bitmask_set( unsigned char *mask, size_t offset, size_t len )
{
unsigned int start_bits, end_bits;
start_bits = 8 - ( offset % 8 );
if( start_bits != 8 )
{
size_t first_byte_idx = offset / 8;
/* Special case */
if( len <= start_bits )
{
for( ; len != 0; len-- )
mask[first_byte_idx] |= 1 << ( start_bits - len );
/* Avoid potential issues with offset or len becoming invalid */
return;
}
offset += start_bits; /* Now offset % 8 == 0 */
len -= start_bits;
for( ; start_bits != 0; start_bits-- )
mask[first_byte_idx] |= 1 << ( start_bits - 1 );
}
end_bits = len % 8;
if( end_bits != 0 )
{
size_t last_byte_idx = ( offset + len ) / 8;
len -= end_bits; /* Now len % 8 == 0 */
for( ; end_bits != 0; end_bits-- )
mask[last_byte_idx] |= 1 << ( 8 - end_bits );
}
memset( mask + offset / 8, 0xFF, len / 8 );
}
/*
* Check that bitmask is full
*/
static int ssl_bitmask_check( unsigned char *mask, size_t len )
{
size_t i;
for( i = 0; i < len / 8; i++ )
if( mask[i] != 0xFF )
return( -1 );
for( i = 0; i < len % 8; i++ )
if( ( mask[len / 8] & ( 1 << ( 7 - i ) ) ) == 0 )
return( -1 );
return( 0 );
}
/* msg_len does not include the handshake header */
static size_t ssl_get_reassembly_buffer_size( size_t msg_len,
unsigned add_bitmap )
{
size_t alloc_len;
alloc_len = 12; /* Handshake header */
alloc_len += msg_len; /* Content buffer */
if( add_bitmap )
alloc_len += msg_len / 8 + ( msg_len % 8 != 0 ); /* Bitmap */
return( alloc_len );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static uint32_t ssl_get_hs_total_len( mbedtls_ssl_context const *ssl )
{
return( ( ssl->in_msg[1] << 16 ) |
( ssl->in_msg[2] << 8 ) |
ssl->in_msg[3] );
}
int mbedtls_ssl_prepare_handshake_record( mbedtls_ssl_context *ssl )
{
if( ssl->in_msglen < mbedtls_ssl_hs_hdr_len( ssl ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "handshake message too short: %d",
ssl->in_msglen ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
ssl->in_hslen = mbedtls_ssl_hs_hdr_len( ssl ) + ssl_get_hs_total_len( ssl );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "handshake message: msglen ="
" %d, type = %d, hslen = %d",
ssl->in_msglen, ssl->in_msg[0], ssl->in_hslen ) );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned int recv_msg_seq = ( ssl->in_msg[4] << 8 ) | ssl->in_msg[5];
if( ssl_check_hs_header( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid handshake header" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
if( ssl->handshake != NULL &&
( ( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER &&
recv_msg_seq != ssl->handshake->in_msg_seq ) ||
( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER &&
ssl->in_msg[0] != MBEDTLS_SSL_HS_CLIENT_HELLO ) ) )
{
if( recv_msg_seq > ssl->handshake->in_msg_seq )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "received future handshake message of sequence number %u (next %u)",
recv_msg_seq,
ssl->handshake->in_msg_seq ) );
return( MBEDTLS_ERR_SSL_EARLY_MESSAGE );
}
/* Retransmit only on last message from previous flight, to avoid
* too many retransmissions.
* Besides, No sane server ever retransmits HelloVerifyRequest */
if( recv_msg_seq == ssl->handshake->in_flight_start_seq - 1 &&
ssl->in_msg[0] != MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "received message from last flight, "
"message_seq = %d, start_of_flight = %d",
recv_msg_seq,
ssl->handshake->in_flight_start_seq ) );
if( ( ret = mbedtls_ssl_resend( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_resend", ret );
return( ret );
}
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "dropping out-of-sequence message: "
"message_seq = %d, expected = %d",
recv_msg_seq,
ssl->handshake->in_msg_seq ) );
}
return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING );
}
/* Wait until message completion to increment in_msg_seq */
/* Message reassembly is handled alongside buffering of future
* messages; the commonality is that both handshake fragments and
* future messages cannot be forwarded immediately to the
* handshake logic layer. */
if( ssl_hs_is_proper_fragment( ssl ) == 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "found fragmented DTLS handshake message" ) );
return( MBEDTLS_ERR_SSL_EARLY_MESSAGE );
}
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* With TLS we don't handle fragmentation (for now) */
if( ssl->in_msglen < ssl->in_hslen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "TLS handshake fragmentation not supported" ) );
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
return( 0 );
}
void mbedtls_ssl_update_handshake_status( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER && hs != NULL )
{
ssl->handshake->update_checksum( ssl, ssl->in_msg, ssl->in_hslen );
}
/* Handshake message is complete, increment counter */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL )
{
unsigned offset;
mbedtls_ssl_hs_buffer *hs_buf;
/* Increment handshake sequence number */
hs->in_msg_seq++;
/*
* Clear up handshake buffering and reassembly structure.
*/
/* Free first entry */
ssl_buffering_free_slot( ssl, 0 );
/* Shift all other entries */
for( offset = 0, hs_buf = &hs->buffering.hs[0];
offset + 1 < MBEDTLS_SSL_MAX_BUFFERED_HS;
offset++, hs_buf++ )
{
*hs_buf = *(hs_buf + 1);
}
/* Create a fresh last entry */
memset( hs_buf, 0, sizeof( mbedtls_ssl_hs_buffer ) );
}
#endif
}
/*
* DTLS anti-replay: RFC 6347 4.1.2.6
*
* in_window is a field of bits numbered from 0 (lsb) to 63 (msb).
* Bit n is set iff record number in_window_top - n has been seen.
*
* Usually, in_window_top is the last record number seen and the lsb of
* in_window is set. The only exception is the initial state (record number 0
* not seen yet).
*/
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
static void ssl_dtls_replay_reset( mbedtls_ssl_context *ssl )
{
ssl->in_window_top = 0;
ssl->in_window = 0;
}
static inline uint64_t ssl_load_six_bytes( unsigned char *buf )
{
return( ( (uint64_t) buf[0] << 40 ) |
( (uint64_t) buf[1] << 32 ) |
( (uint64_t) buf[2] << 24 ) |
( (uint64_t) buf[3] << 16 ) |
( (uint64_t) buf[4] << 8 ) |
( (uint64_t) buf[5] ) );
}
static int mbedtls_ssl_dtls_record_replay_check( mbedtls_ssl_context *ssl, uint8_t *record_in_ctr )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *original_in_ctr;
// save original in_ctr
original_in_ctr = ssl->in_ctr;
// use counter from record
ssl->in_ctr = record_in_ctr;
ret = mbedtls_ssl_dtls_replay_check( (mbedtls_ssl_context const *) ssl );
// restore the counter
ssl->in_ctr = original_in_ctr;
return ret;
}
/*
* Return 0 if sequence number is acceptable, -1 otherwise
*/
int mbedtls_ssl_dtls_replay_check( mbedtls_ssl_context const *ssl )
{
uint64_t rec_seqnum = ssl_load_six_bytes( ssl->in_ctr + 2 );
uint64_t bit;
if( ssl->conf->anti_replay == MBEDTLS_SSL_ANTI_REPLAY_DISABLED )
return( 0 );
if( rec_seqnum > ssl->in_window_top )
return( 0 );
bit = ssl->in_window_top - rec_seqnum;
if( bit >= 64 )
return( -1 );
if( ( ssl->in_window & ( (uint64_t) 1 << bit ) ) != 0 )
return( -1 );
return( 0 );
}
/*
* Update replay window on new validated record
*/
void mbedtls_ssl_dtls_replay_update( mbedtls_ssl_context *ssl )
{
uint64_t rec_seqnum = ssl_load_six_bytes( ssl->in_ctr + 2 );
if( ssl->conf->anti_replay == MBEDTLS_SSL_ANTI_REPLAY_DISABLED )
return;
if( rec_seqnum > ssl->in_window_top )
{
/* Update window_top and the contents of the window */
uint64_t shift = rec_seqnum - ssl->in_window_top;
if( shift >= 64 )
ssl->in_window = 1;
else
{
ssl->in_window <<= shift;
ssl->in_window |= 1;
}
ssl->in_window_top = rec_seqnum;
}
else
{
/* Mark that number as seen in the current window */
uint64_t bit = ssl->in_window_top - rec_seqnum;
if( bit < 64 ) /* Always true, but be extra sure */
ssl->in_window |= (uint64_t) 1 << bit;
}
}
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) && defined(MBEDTLS_SSL_SRV_C)
/* Forward declaration */
static int ssl_session_reset_int( mbedtls_ssl_context *ssl, int partial );
/*
* Without any SSL context, check if a datagram looks like a ClientHello with
* a valid cookie, and if it doesn't, generate a HelloVerifyRequest message.
* Both input and output include full DTLS headers.
*
* - if cookie is valid, return 0
* - if ClientHello looks superficially valid but cookie is not,
* fill obuf and set olen, then
* return MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED
* - otherwise return a specific error code
*/
static int ssl_check_dtls_clihlo_cookie(
mbedtls_ssl_cookie_write_t *f_cookie_write,
mbedtls_ssl_cookie_check_t *f_cookie_check,
void *p_cookie,
const unsigned char *cli_id, size_t cli_id_len,
const unsigned char *in, size_t in_len,
unsigned char *obuf, size_t buf_len, size_t *olen )
{
size_t sid_len, cookie_len;
unsigned char *p;
/*
* Structure of ClientHello with record and handshake headers,
* and expected values. We don't need to check a lot, more checks will be
* done when actually parsing the ClientHello - skipping those checks
* avoids code duplication and does not make cookie forging any easier.
*
* 0-0 ContentType type; copied, must be handshake
* 1-2 ProtocolVersion version; copied
* 3-4 uint16 epoch; copied, must be 0
* 5-10 uint48 sequence_number; copied
* 11-12 uint16 length; (ignored)
*
* 13-13 HandshakeType msg_type; (ignored)
* 14-16 uint24 length; (ignored)
* 17-18 uint16 message_seq; copied
* 19-21 uint24 fragment_offset; copied, must be 0
* 22-24 uint24 fragment_length; (ignored)
*
* 25-26 ProtocolVersion client_version; (ignored)
* 27-58 Random random; (ignored)
* 59-xx SessionID session_id; 1 byte len + sid_len content
* 60+ opaque cookie<0..2^8-1>; 1 byte len + content
* ...
*
* Minimum length is 61 bytes.
*/
if( in_len < 61 ||
in[0] != MBEDTLS_SSL_MSG_HANDSHAKE ||
in[3] != 0 || in[4] != 0 ||
in[19] != 0 || in[20] != 0 || in[21] != 0 )
{
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
}
sid_len = in[59];
if( sid_len > in_len - 61 )
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
cookie_len = in[60 + sid_len];
if( cookie_len > in_len - 60 )
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
if( f_cookie_check( p_cookie, in + sid_len + 61, cookie_len,
cli_id, cli_id_len ) == 0 )
{
/* Valid cookie */
return( 0 );
}
/*
* If we get here, we've got an invalid cookie, let's prepare HVR.
*
* 0-0 ContentType type; copied
* 1-2 ProtocolVersion version; copied
* 3-4 uint16 epoch; copied
* 5-10 uint48 sequence_number; copied
* 11-12 uint16 length; olen - 13
*
* 13-13 HandshakeType msg_type; hello_verify_request
* 14-16 uint24 length; olen - 25
* 17-18 uint16 message_seq; copied
* 19-21 uint24 fragment_offset; copied
* 22-24 uint24 fragment_length; olen - 25
*
* 25-26 ProtocolVersion server_version; 0xfe 0xff
* 27-27 opaque cookie<0..2^8-1>; cookie_len = olen - 27, cookie
*
* Minimum length is 28.
*/
if( buf_len < 28 )
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
/* Copy most fields and adapt others */
memcpy( obuf, in, 25 );
obuf[13] = MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST;
obuf[25] = 0xfe;
obuf[26] = 0xff;
/* Generate and write actual cookie */
p = obuf + 28;
if( f_cookie_write( p_cookie,
&p, obuf + buf_len, cli_id, cli_id_len ) != 0 )
{
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
*olen = p - obuf;
/* Go back and fill length fields */
obuf[27] = (unsigned char)( *olen - 28 );
obuf[14] = obuf[22] = (unsigned char)( ( *olen - 25 ) >> 16 );
obuf[15] = obuf[23] = (unsigned char)( ( *olen - 25 ) >> 8 );
obuf[16] = obuf[24] = (unsigned char)( ( *olen - 25 ) );
obuf[11] = (unsigned char)( ( *olen - 13 ) >> 8 );
obuf[12] = (unsigned char)( ( *olen - 13 ) );
return( MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED );
}
/*
* Handle possible client reconnect with the same UDP quadruplet
* (RFC 6347 Section 4.2.8).
*
* Called by ssl_parse_record_header() in case we receive an epoch 0 record
* that looks like a ClientHello.
*
* - if the input looks like a ClientHello without cookies,
* send back HelloVerifyRequest, then
* return MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED
* - if the input looks like a ClientHello with a valid cookie,
* reset the session of the current context, and
* return MBEDTLS_ERR_SSL_CLIENT_RECONNECT
* - if anything goes wrong, return a specific error code
*
* mbedtls_ssl_read_record() will ignore the record if anything else than
* MBEDTLS_ERR_SSL_CLIENT_RECONNECT or 0 is returned, although this function
* cannot not return 0.
*/
static int ssl_handle_possible_reconnect( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len;
if( ssl->conf->f_cookie_write == NULL ||
ssl->conf->f_cookie_check == NULL )
{
/* If we can't use cookies to verify reachability of the peer,
* drop the record. */
return( 0 );
}
ret = ssl_check_dtls_clihlo_cookie(
ssl->conf->f_cookie_write,
ssl->conf->f_cookie_check,
ssl->conf->p_cookie,
ssl->cli_id, ssl->cli_id_len,
ssl->in_buf, ssl->in_left,
ssl->out_buf, MBEDTLS_SSL_OUT_CONTENT_LEN, &len );
MBEDTLS_SSL_DEBUG_RET( 2, "ssl_check_dtls_clihlo_cookie", ret );
if( ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED )
{
/* Don't check write errors as we can't do anything here.
* If the error is permanent we'll catch it later,
* if it's not, then hopefully it'll work next time. */
(void) ssl->f_send( ssl->p_bio, ssl->out_buf, len );
ret = 0;
}
if( ret == 0 )
{
/* Got a valid cookie, partially reset context */
if( ( ret = ssl_session_reset_int( ssl, 1 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "reset", ret );
return( ret );
}
return( MBEDTLS_ERR_SSL_CLIENT_RECONNECT );
}
return( ret );
}
#endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE && MBEDTLS_SSL_SRV_C */
static int ssl_check_record_type( uint8_t record_type )
{
if( record_type != MBEDTLS_SSL_MSG_HANDSHAKE &&
record_type != MBEDTLS_SSL_MSG_ALERT &&
record_type != MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC &&
record_type != MBEDTLS_SSL_MSG_APPLICATION_DATA )
{
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
return( 0 );
}
/*
* ContentType type;
* ProtocolVersion version;
* uint16 epoch; // DTLS only
* uint48 sequence_number; // DTLS only
* uint16 length;
*
* Return 0 if header looks sane (and, for DTLS, the record is expected)
* MBEDTLS_ERR_SSL_INVALID_RECORD if the header looks bad,
* MBEDTLS_ERR_SSL_UNEXPECTED_RECORD (DTLS only) if sane but unexpected.
*
* With DTLS, mbedtls_ssl_read_record() will:
* 1. proceed with the record if this function returns 0
* 2. drop only the current record if this function returns UNEXPECTED_RECORD
* 3. return CLIENT_RECONNECT if this function return that value
* 4. drop the whole datagram if this function returns anything else.
* Point 2 is needed when the peer is resending, and we have already received
* the first record from a datagram but are still waiting for the others.
*/
static int ssl_parse_record_header( mbedtls_ssl_context const *ssl,
unsigned char *buf,
size_t len,
mbedtls_record *rec )
{
int major_ver, minor_ver;
size_t const rec_hdr_type_offset = 0;
size_t const rec_hdr_type_len = 1;
size_t const rec_hdr_version_offset = rec_hdr_type_offset +
rec_hdr_type_len;
size_t const rec_hdr_version_len = 2;
size_t const rec_hdr_ctr_len = 8;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
uint32_t rec_epoch;
size_t const rec_hdr_ctr_offset = rec_hdr_version_offset +
rec_hdr_version_len;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
size_t const rec_hdr_cid_offset = rec_hdr_ctr_offset +
rec_hdr_ctr_len;
size_t rec_hdr_cid_len = 0;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#endif /* MBEDTLS_SSL_PROTO_DTLS */
size_t rec_hdr_len_offset; /* To be determined */
size_t const rec_hdr_len_len = 2;
/*
* Check minimum lengths for record header.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
rec_hdr_len_offset = rec_hdr_ctr_offset + rec_hdr_ctr_len;
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
{
rec_hdr_len_offset = rec_hdr_version_offset + rec_hdr_version_len;
}
if( len < rec_hdr_len_offset + rec_hdr_len_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "datagram of length %u too small to hold DTLS record header of length %u",
(unsigned) len,
(unsigned)( rec_hdr_len_len + rec_hdr_len_len ) ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
/*
* Parse and validate record content type
*/
rec->type = buf[ rec_hdr_type_offset ];
/* Check record content type */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
rec->cid_len = 0;
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->conf->cid_len != 0 &&
rec->type == MBEDTLS_SSL_MSG_CID )
{
/* Shift pointers to account for record header including CID
* struct {
* ContentType special_type = tls12_cid;
* ProtocolVersion version;
* uint16 epoch;
* uint48 sequence_number;
* opaque cid[cid_length]; // Additional field compared to
* // default DTLS record format
* uint16 length;
* opaque enc_content[DTLSCiphertext.length];
* } DTLSCiphertext;
*/
/* So far, we only support static CID lengths
* fixed in the configuration. */
rec_hdr_cid_len = ssl->conf->cid_len;
rec_hdr_len_offset += rec_hdr_cid_len;
if( len < rec_hdr_len_offset + rec_hdr_len_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "datagram of length %u too small to hold DTLS record header including CID, length %u",
(unsigned) len,
(unsigned)( rec_hdr_len_offset + rec_hdr_len_len ) ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
/* configured CID len is guaranteed at most 255, see
* MBEDTLS_SSL_CID_OUT_LEN_MAX in check_config.h */
rec->cid_len = (uint8_t) rec_hdr_cid_len;
memcpy( rec->cid, buf + rec_hdr_cid_offset, rec_hdr_cid_len );
}
else
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
{
if( ssl_check_record_type( rec->type ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "unknown record type %u",
(unsigned) rec->type ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
}
/*
* Parse and validate record version
*/
rec->ver[0] = buf[ rec_hdr_version_offset + 0 ];
rec->ver[1] = buf[ rec_hdr_version_offset + 1 ];
mbedtls_ssl_read_version( &major_ver, &minor_ver,
ssl->conf->transport,
&rec->ver[0] );
if( major_ver != ssl->major_ver )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "major version mismatch" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
if( minor_ver > ssl->conf->max_minor_ver )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "minor version mismatch" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
/*
* Parse/Copy record sequence number.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Copy explicit record sequence number from input buffer. */
memcpy( &rec->ctr[0], buf + rec_hdr_ctr_offset,
rec_hdr_ctr_len );
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
{
/* Copy implicit record sequence number from SSL context structure. */
memcpy( &rec->ctr[0], ssl->in_ctr, rec_hdr_ctr_len );
}
/*
* Parse record length.
*/
rec->data_offset = rec_hdr_len_offset + rec_hdr_len_len;
rec->data_len = ( (size_t) buf[ rec_hdr_len_offset + 0 ] << 8 ) |
( (size_t) buf[ rec_hdr_len_offset + 1 ] << 0 );
MBEDTLS_SSL_DEBUG_BUF( 4, "input record header", buf, rec->data_offset );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "input record: msgtype = %d, "
"version = [%d:%d], msglen = %d",
rec->type,
major_ver, minor_ver, rec->data_len ) );
rec->buf = buf;
rec->buf_len = rec->data_offset + rec->data_len;
if( rec->data_len == 0 )
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
/*
* DTLS-related tests.
* Check epoch before checking length constraint because
* the latter varies with the epoch. E.g., if a ChangeCipherSpec
* message gets duplicated before the corresponding Finished message,
* the second ChangeCipherSpec should be discarded because it belongs
* to an old epoch, but not because its length is shorter than
* the minimum record length for packets using the new record transform.
* Note that these two kinds of failures are handled differently,
* as an unexpected record is silently skipped but an invalid
* record leads to the entire datagram being dropped.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
rec_epoch = ( rec->ctr[0] << 8 ) | rec->ctr[1];
/* Check that the datagram is large enough to contain a record
* of the advertised length. */
if( len < rec->data_offset + rec->data_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Datagram of length %u too small to contain record of advertised length %u.",
(unsigned) len,
(unsigned)( rec->data_offset + rec->data_len ) ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
/* Records from other, non-matching epochs are silently discarded.
* (The case of same-port Client reconnects must be considered in
* the caller). */
if( rec_epoch != ssl->in_epoch )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "record from another epoch: "
"expected %d, received %d",
ssl->in_epoch, rec_epoch ) );
/* Records from the next epoch are considered for buffering
* (concretely: early Finished messages). */
if( rec_epoch == (unsigned) ssl->in_epoch + 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Consider record for buffering" ) );
return( MBEDTLS_ERR_SSL_EARLY_MESSAGE );
}
return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD );
}
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
/* For records from the correct epoch, check whether their
* sequence number has been seen before. */
else if( mbedtls_ssl_dtls_record_replay_check( (mbedtls_ssl_context *) ssl,
&rec->ctr[0] ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "replayed record" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD );
}
#endif
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
return( 0 );
}
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) && defined(MBEDTLS_SSL_SRV_C)
static int ssl_check_client_reconnect( mbedtls_ssl_context *ssl )
{
unsigned int rec_epoch = ( ssl->in_ctr[0] << 8 ) | ssl->in_ctr[1];
/*
* Check for an epoch 0 ClientHello. We can't use in_msg here to
* access the first byte of record content (handshake type), as we
* have an active transform (possibly iv_len != 0), so use the
* fact that the record header len is 13 instead.
*/
if( rec_epoch == 0 &&
ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER &&
ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->in_left > 13 &&
ssl->in_buf[13] == MBEDTLS_SSL_HS_CLIENT_HELLO )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "possible client reconnect "
"from the same port" ) );
return( ssl_handle_possible_reconnect( ssl ) );
}
return( 0 );
}
#endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE && MBEDTLS_SSL_SRV_C */
/*
* If applicable, decrypt record content
*/
static int ssl_prepare_record_content( mbedtls_ssl_context *ssl,
mbedtls_record *rec )
{
int ret, done = 0;
MBEDTLS_SSL_DEBUG_BUF( 4, "input record from network",
rec->buf, rec->buf_len );
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_read != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_read()" ) );
ret = mbedtls_ssl_hw_record_read( ssl );
if( ret != 0 && ret != MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_read", ret );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
if( ret == 0 )
done = 1;
}
#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
if( !done && ssl->transform_in != NULL )
{
unsigned char const old_msg_type = rec->type;
if( ( ret = mbedtls_ssl_decrypt_buf( ssl, ssl->transform_in,
rec ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_decrypt_buf", ret );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( ret == MBEDTLS_ERR_SSL_UNEXPECTED_CID &&
ssl->conf->ignore_unexpected_cid
== MBEDTLS_SSL_UNEXPECTED_CID_IGNORE )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ignoring unexpected CID" ) );
ret = MBEDTLS_ERR_SSL_CONTINUE_PROCESSING;
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
return( ret );
}
if( old_msg_type != rec->type )
{
MBEDTLS_SSL_DEBUG_MSG( 4, ( "record type after decrypt (before %d): %d",
old_msg_type, rec->type ) );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "input payload after decrypt",
rec->buf + rec->data_offset, rec->data_len );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* We have already checked the record content type
* in ssl_parse_record_header(), failing or silently
* dropping the record in the case of an unknown type.
*
* Since with the use of CIDs, the record content type
* might change during decryption, re-check the record
* content type, but treat a failure as fatal this time. */
if( ssl_check_record_type( rec->type ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "unknown record type" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
if( rec->data_len == 0 )
{
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3
&& rec->type != MBEDTLS_SSL_MSG_APPLICATION_DATA )
{
/* TLS v1.2 explicitly disallows zero-length messages which are not application data */
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid zero-length message type: %d", ssl->in_msgtype ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
ssl->nb_zero++;
/*
* Three or more empty messages may be a DoS attack
* (excessive CPU consumption).
*/
if( ssl->nb_zero > 3 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "received four consecutive empty "
"messages, possible DoS attack" ) );
/* Treat the records as if they were not properly authenticated,
* thereby failing the connection if we see more than allowed
* by the configured bad MAC threshold. */
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
}
else
ssl->nb_zero = 0;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
; /* in_ctr read from peer, not maintained internally */
}
else
#endif
{
unsigned i;
for( i = 8; i > ssl_ep_len( ssl ); i-- )
if( ++ssl->in_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == ssl_ep_len( ssl ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "incoming message counter would wrap" ) );
return( MBEDTLS_ERR_SSL_COUNTER_WRAPPING );
}
}
}
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
mbedtls_ssl_dtls_replay_update( ssl );
}
#endif
/* Check actual (decrypted) record content length against
* configured maximum. */
if( ssl->in_msglen > MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
return( 0 );
}
static void ssl_handshake_wrapup_free_hs_transform( mbedtls_ssl_context *ssl );
/*
* Read a record.
*
* Silently ignore non-fatal alert (and for DTLS, invalid records as well,
* RFC 6347 4.1.2.7) and continue reading until a valid record is found.
*
*/
/* Helper functions for mbedtls_ssl_read_record(). */
static int ssl_consume_current_message( mbedtls_ssl_context *ssl );
static int ssl_get_next_record( mbedtls_ssl_context *ssl );
static int ssl_record_is_in_progress( mbedtls_ssl_context *ssl );
int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl,
unsigned update_hs_digest )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> read record" ) );
if( ssl->keep_current_message == 0 )
{
do {
ret = ssl_consume_current_message( ssl );
if( ret != 0 )
return( ret );
if( ssl_record_is_in_progress( ssl ) == 0 )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
int have_buffered = 0;
/* We only check for buffered messages if the
* current datagram is fully consumed. */
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl_next_record_is_in_datagram( ssl ) == 0 )
{
if( ssl_load_buffered_message( ssl ) == 0 )
have_buffered = 1;
}
if( have_buffered == 0 )
#endif /* MBEDTLS_SSL_PROTO_DTLS */
{
ret = ssl_get_next_record( ssl );
if( ret == MBEDTLS_ERR_SSL_CONTINUE_PROCESSING )
continue;
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_get_next_record" ), ret );
return( ret );
}
}
}
ret = mbedtls_ssl_handle_message_type( ssl );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ret == MBEDTLS_ERR_SSL_EARLY_MESSAGE )
{
/* Buffer future message */
ret = ssl_buffer_message( ssl );
if( ret != 0 )
return( ret );
ret = MBEDTLS_ERR_SSL_CONTINUE_PROCESSING;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
} while( MBEDTLS_ERR_SSL_NON_FATAL == ret ||
MBEDTLS_ERR_SSL_CONTINUE_PROCESSING == ret );
if( 0 != ret )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ssl_handle_message_type" ), ret );
return( ret );
}
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
update_hs_digest == 1 )
{
mbedtls_ssl_update_handshake_status( ssl );
}
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "reuse previously read message" ) );
ssl->keep_current_message = 0;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= read record" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static int ssl_next_record_is_in_datagram( mbedtls_ssl_context *ssl )
{
if( ssl->in_left > ssl->next_record_offset )
return( 1 );
return( 0 );
}
static int ssl_load_buffered_message( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
mbedtls_ssl_hs_buffer * hs_buf;
int ret = 0;
if( hs == NULL )
return( -1 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> ssl_load_buffered_messsage" ) );
if( ssl->state == MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC ||
ssl->state == MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC )
{
/* Check if we have seen a ChangeCipherSpec before.
* If yes, synthesize a CCS record. */
if( !hs->buffering.seen_ccs )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "CCS not seen in the current flight" ) );
ret = -1;
goto exit;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Injecting buffered CCS message" ) );
ssl->in_msgtype = MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC;
ssl->in_msglen = 1;
ssl->in_msg[0] = 1;
/* As long as they are equal, the exact value doesn't matter. */
ssl->in_left = 0;
ssl->next_record_offset = 0;
hs->buffering.seen_ccs = 0;
goto exit;
}
#if defined(MBEDTLS_DEBUG_C)
/* Debug only */
{
unsigned offset;
for( offset = 1; offset < MBEDTLS_SSL_MAX_BUFFERED_HS; offset++ )
{
hs_buf = &hs->buffering.hs[offset];
if( hs_buf->is_valid == 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Future message with sequence number %u %s buffered.",
hs->in_msg_seq + offset,
hs_buf->is_complete ? "fully" : "partially" ) );
}
}
}
#endif /* MBEDTLS_DEBUG_C */
/* Check if we have buffered and/or fully reassembled the
* next handshake message. */
hs_buf = &hs->buffering.hs[0];
if( ( hs_buf->is_valid == 1 ) && ( hs_buf->is_complete == 1 ) )
{
/* Synthesize a record containing the buffered HS message. */
size_t msg_len = ( hs_buf->data[1] << 16 ) |
( hs_buf->data[2] << 8 ) |
hs_buf->data[3];
/* Double-check that we haven't accidentally buffered
* a message that doesn't fit into the input buffer. */
if( msg_len + 12 > MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Next handshake message has been buffered - load" ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "Buffered handshake message (incl. header)",
hs_buf->data, msg_len + 12 );
ssl->in_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->in_hslen = msg_len + 12;
ssl->in_msglen = msg_len + 12;
memcpy( ssl->in_msg, hs_buf->data, ssl->in_hslen );
ret = 0;
goto exit;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Next handshake message %u not or only partially bufffered",
hs->in_msg_seq ) );
}
ret = -1;
exit:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= ssl_load_buffered_message" ) );
return( ret );
}
static int ssl_buffer_make_space( mbedtls_ssl_context *ssl,
size_t desired )
{
int offset;
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Attempt to free buffered messages to have %u bytes available",
(unsigned) desired ) );
/* Get rid of future records epoch first, if such exist. */
ssl_free_buffered_record( ssl );
/* Check if we have enough space available now. */
if( desired <= ( MBEDTLS_SSL_DTLS_MAX_BUFFERING -
hs->buffering.total_bytes_buffered ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Enough space available after freeing future epoch record" ) );
return( 0 );
}
/* We don't have enough space to buffer the next expected handshake
* message. Remove buffers used for future messages to gain space,
* starting with the most distant one. */
for( offset = MBEDTLS_SSL_MAX_BUFFERED_HS - 1;
offset >= 0; offset-- )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Free buffering slot %d to make space for reassembly of next handshake message",
offset ) );
ssl_buffering_free_slot( ssl, (uint8_t) offset );
/* Check if we have enough space available now. */
if( desired <= ( MBEDTLS_SSL_DTLS_MAX_BUFFERING -
hs->buffering.total_bytes_buffered ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Enough space available after freeing buffered HS messages" ) );
return( 0 );
}
}
return( -1 );
}
static int ssl_buffer_message( mbedtls_ssl_context *ssl )
{
int ret = 0;
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
if( hs == NULL )
return( 0 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> ssl_buffer_message" ) );
switch( ssl->in_msgtype )
{
case MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Remember CCS message" ) );
hs->buffering.seen_ccs = 1;
break;
case MBEDTLS_SSL_MSG_HANDSHAKE:
{
unsigned recv_msg_seq_offset;
unsigned recv_msg_seq = ( ssl->in_msg[4] << 8 ) | ssl->in_msg[5];
mbedtls_ssl_hs_buffer *hs_buf;
size_t msg_len = ssl->in_hslen - 12;
/* We should never receive an old handshake
* message - double-check nonetheless. */
if( recv_msg_seq < ssl->handshake->in_msg_seq )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
recv_msg_seq_offset = recv_msg_seq - ssl->handshake->in_msg_seq;
if( recv_msg_seq_offset >= MBEDTLS_SSL_MAX_BUFFERED_HS )
{
/* Silently ignore -- message too far in the future */
MBEDTLS_SSL_DEBUG_MSG( 2,
( "Ignore future HS message with sequence number %u, "
"buffering window %u - %u",
recv_msg_seq, ssl->handshake->in_msg_seq,
ssl->handshake->in_msg_seq + MBEDTLS_SSL_MAX_BUFFERED_HS - 1 ) );
goto exit;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffering HS message with sequence number %u, offset %u ",
recv_msg_seq, recv_msg_seq_offset ) );
hs_buf = &hs->buffering.hs[ recv_msg_seq_offset ];
/* Check if the buffering for this seq nr has already commenced. */
if( !hs_buf->is_valid )
{
size_t reassembly_buf_sz;
hs_buf->is_fragmented =
( ssl_hs_is_proper_fragment( ssl ) == 1 );
/* We copy the message back into the input buffer
* after reassembly, so check that it's not too large.
* This is an implementation-specific limitation
* and not one from the standard, hence it is not
* checked in ssl_check_hs_header(). */
if( msg_len + 12 > MBEDTLS_SSL_IN_CONTENT_LEN )
{
/* Ignore message */
goto exit;
}
/* Check if we have enough space to buffer the message. */
if( hs->buffering.total_bytes_buffered >
MBEDTLS_SSL_DTLS_MAX_BUFFERING )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
reassembly_buf_sz = ssl_get_reassembly_buffer_size( msg_len,
hs_buf->is_fragmented );
if( reassembly_buf_sz > ( MBEDTLS_SSL_DTLS_MAX_BUFFERING -
hs->buffering.total_bytes_buffered ) )
{
if( recv_msg_seq_offset > 0 )
{
/* If we can't buffer a future message because
* of space limitations -- ignore. */
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffering of future message of size %u would exceed the compile-time limit %u (already %u bytes buffered) -- ignore\n",
(unsigned) msg_len, MBEDTLS_SSL_DTLS_MAX_BUFFERING,
(unsigned) hs->buffering.total_bytes_buffered ) );
goto exit;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffering of future message of size %u would exceed the compile-time limit %u (already %u bytes buffered) -- attempt to make space by freeing buffered future messages\n",
(unsigned) msg_len, MBEDTLS_SSL_DTLS_MAX_BUFFERING,
(unsigned) hs->buffering.total_bytes_buffered ) );
}
if( ssl_buffer_make_space( ssl, reassembly_buf_sz ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Reassembly of next message of size %u (%u with bitmap) would exceed the compile-time limit %u (already %u bytes buffered) -- fail\n",
(unsigned) msg_len,
(unsigned) reassembly_buf_sz,
MBEDTLS_SSL_DTLS_MAX_BUFFERING,
(unsigned) hs->buffering.total_bytes_buffered ) );
ret = MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;
goto exit;
}
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "initialize reassembly, total length = %d",
msg_len ) );
hs_buf->data = mbedtls_calloc( 1, reassembly_buf_sz );
if( hs_buf->data == NULL )
{
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto exit;
}
hs_buf->data_len = reassembly_buf_sz;
/* Prepare final header: copy msg_type, length and message_seq,
* then add standardised fragment_offset and fragment_length */
memcpy( hs_buf->data, ssl->in_msg, 6 );
memset( hs_buf->data + 6, 0, 3 );
memcpy( hs_buf->data + 9, hs_buf->data + 1, 3 );
hs_buf->is_valid = 1;
hs->buffering.total_bytes_buffered += reassembly_buf_sz;
}
else
{
/* Make sure msg_type and length are consistent */
if( memcmp( hs_buf->data, ssl->in_msg, 4 ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Fragment header mismatch - ignore" ) );
/* Ignore */
goto exit;
}
}
if( !hs_buf->is_complete )
{
size_t frag_len, frag_off;
unsigned char * const msg = hs_buf->data + 12;
/*
* Check and copy current fragment
*/
/* Validation of header fields already done in
* mbedtls_ssl_prepare_handshake_record(). */
frag_off = ssl_get_hs_frag_off( ssl );
frag_len = ssl_get_hs_frag_len( ssl );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "adding fragment, offset = %d, length = %d",
frag_off, frag_len ) );
memcpy( msg + frag_off, ssl->in_msg + 12, frag_len );
if( hs_buf->is_fragmented )
{
unsigned char * const bitmask = msg + msg_len;
ssl_bitmask_set( bitmask, frag_off, frag_len );
hs_buf->is_complete = ( ssl_bitmask_check( bitmask,
msg_len ) == 0 );
}
else
{
hs_buf->is_complete = 1;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "message %scomplete",
hs_buf->is_complete ? "" : "not yet " ) );
}
break;
}
default:
/* We don't buffer other types of messages. */
break;
}
exit:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= ssl_buffer_message" ) );
return( ret );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static int ssl_consume_current_message( mbedtls_ssl_context *ssl )
{
/*
* Consume last content-layer message and potentially
* update in_msglen which keeps track of the contents'
* consumption state.
*
* (1) Handshake messages:
* Remove last handshake message, move content
* and adapt in_msglen.
*
* (2) Alert messages:
* Consume whole record content, in_msglen = 0.
*
* (3) Change cipher spec:
* Consume whole record content, in_msglen = 0.
*
* (4) Application data:
* Don't do anything - the record layer provides
* the application data as a stream transport
* and consumes through mbedtls_ssl_read only.
*
*/
/* Case (1): Handshake messages */
if( ssl->in_hslen != 0 )
{
/* Hard assertion to be sure that no application data
* is in flight, as corrupting ssl->in_msglen during
* ssl->in_offt != NULL is fatal. */
if( ssl->in_offt != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* Get next Handshake message in the current record
*/
/* Notes:
* (1) in_hslen is not necessarily the size of the
* current handshake content: If DTLS handshake
* fragmentation is used, that's the fragment
* size instead. Using the total handshake message
* size here is faulty and should be changed at
* some point.
* (2) While it doesn't seem to cause problems, one
* has to be very careful not to assume that in_hslen
* is always <= in_msglen in a sensible communication.
* Again, it's wrong for DTLS handshake fragmentation.
* The following check is therefore mandatory, and
* should not be treated as a silently corrected assertion.
* Additionally, ssl->in_hslen might be arbitrarily out of
* bounds after handling a DTLS message with an unexpected
* sequence number, see mbedtls_ssl_prepare_handshake_record.
*/
if( ssl->in_hslen < ssl->in_msglen )
{
ssl->in_msglen -= ssl->in_hslen;
memmove( ssl->in_msg, ssl->in_msg + ssl->in_hslen,
ssl->in_msglen );
MBEDTLS_SSL_DEBUG_BUF( 4, "remaining content in record",
ssl->in_msg, ssl->in_msglen );
}
else
{
ssl->in_msglen = 0;
}
ssl->in_hslen = 0;
}
/* Case (4): Application data */
else if( ssl->in_offt != NULL )
{
return( 0 );
}
/* Everything else (CCS & Alerts) */
else
{
ssl->in_msglen = 0;
}
return( 0 );
}
static int ssl_record_is_in_progress( mbedtls_ssl_context *ssl )
{
if( ssl->in_msglen > 0 )
return( 1 );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static void ssl_free_buffered_record( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
if( hs == NULL )
return;
if( hs->buffering.future_record.data != NULL )
{
hs->buffering.total_bytes_buffered -=
hs->buffering.future_record.len;
mbedtls_free( hs->buffering.future_record.data );
hs->buffering.future_record.data = NULL;
}
}
static int ssl_load_buffered_record( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
unsigned char * rec;
size_t rec_len;
unsigned rec_epoch;
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM )
return( 0 );
if( hs == NULL )
return( 0 );
rec = hs->buffering.future_record.data;
rec_len = hs->buffering.future_record.len;
rec_epoch = hs->buffering.future_record.epoch;
if( rec == NULL )
return( 0 );
/* Only consider loading future records if the
* input buffer is empty. */
if( ssl_next_record_is_in_datagram( ssl ) == 1 )
return( 0 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> ssl_load_buffered_record" ) );
if( rec_epoch != ssl->in_epoch )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffered record not from current epoch." ) );
goto exit;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Found buffered record from current epoch - load" ) );
/* Double-check that the record is not too large */
if( rec_len > MBEDTLS_SSL_IN_BUFFER_LEN -
(size_t)( ssl->in_hdr - ssl->in_buf ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
memcpy( ssl->in_hdr, rec, rec_len );
ssl->in_left = rec_len;
ssl->next_record_offset = 0;
ssl_free_buffered_record( ssl );
exit:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= ssl_load_buffered_record" ) );
return( 0 );
}
static int ssl_buffer_future_record( mbedtls_ssl_context *ssl,
mbedtls_record const *rec )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
/* Don't buffer future records outside handshakes. */
if( hs == NULL )
return( 0 );
/* Only buffer handshake records (we are only interested
* in Finished messages). */
if( rec->type != MBEDTLS_SSL_MSG_HANDSHAKE )
return( 0 );
/* Don't buffer more than one future epoch record. */
if( hs->buffering.future_record.data != NULL )
return( 0 );
/* Don't buffer record if there's not enough buffering space remaining. */
if( rec->buf_len > ( MBEDTLS_SSL_DTLS_MAX_BUFFERING -
hs->buffering.total_bytes_buffered ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffering of future epoch record of size %u would exceed the compile-time limit %u (already %u bytes buffered) -- ignore\n",
(unsigned) rec->buf_len, MBEDTLS_SSL_DTLS_MAX_BUFFERING,
(unsigned) hs->buffering.total_bytes_buffered ) );
return( 0 );
}
/* Buffer record */
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Buffer record from epoch %u",
ssl->in_epoch + 1 ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "Buffered record", rec->buf, rec->buf_len );
/* ssl_parse_record_header() only considers records
* of the next epoch as candidates for buffering. */
hs->buffering.future_record.epoch = ssl->in_epoch + 1;
hs->buffering.future_record.len = rec->buf_len;
hs->buffering.future_record.data =
mbedtls_calloc( 1, hs->buffering.future_record.len );
if( hs->buffering.future_record.data == NULL )
{
/* If we run out of RAM trying to buffer a
* record from the next epoch, just ignore. */
return( 0 );
}
memcpy( hs->buffering.future_record.data, rec->buf, rec->buf_len );
hs->buffering.total_bytes_buffered += rec->buf_len;
return( 0 );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static int ssl_get_next_record( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_record rec;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/* We might have buffered a future record; if so,
* and if the epoch matches now, load it.
* On success, this call will set ssl->in_left to
* the length of the buffered record, so that
* the calls to ssl_fetch_input() below will
* essentially be no-ops. */
ret = ssl_load_buffered_record( ssl );
if( ret != 0 )
return( ret );
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* Ensure that we have enough space available for the default form
* of TLS / DTLS record headers (5 Bytes for TLS, 13 Bytes for DTLS,
* with no space for CIDs counted in). */
ret = mbedtls_ssl_fetch_input( ssl, mbedtls_ssl_in_hdr_len( ssl ) );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret );
return( ret );
}
ret = ssl_parse_record_header( ssl, ssl->in_hdr, ssl->in_left, &rec );
if( ret != 0 )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
if( ret == MBEDTLS_ERR_SSL_EARLY_MESSAGE )
{
ret = ssl_buffer_future_record( ssl, &rec );
if( ret != 0 )
return( ret );
/* Fall through to handling of unexpected records */
ret = MBEDTLS_ERR_SSL_UNEXPECTED_RECORD;
}
if( ret == MBEDTLS_ERR_SSL_UNEXPECTED_RECORD )
{
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) && defined(MBEDTLS_SSL_SRV_C)
/* Reset in pointers to default state for TLS/DTLS records,
* assuming no CID and no offset between record content and
* record plaintext. */
ssl_update_in_pointers( ssl );
/* Setup internal message pointers from record structure. */
ssl->in_msgtype = rec.type;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->in_len = ssl->in_cid + rec.cid_len;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->in_iv = ssl->in_msg = ssl->in_len + 2;
ssl->in_msglen = rec.data_len;
ret = ssl_check_client_reconnect( ssl );
if( ret != 0 )
return( ret );
#endif
/* Skip unexpected record (but not whole datagram) */
ssl->next_record_offset = rec.buf_len;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "discarding unexpected record "
"(header)" ) );
}
else
{
/* Skip invalid record and the rest of the datagram */
ssl->next_record_offset = 0;
ssl->in_left = 0;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "discarding invalid record "
"(header)" ) );
}
/* Get next record */
return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING );
}
else
#endif
{
return( ret );
}
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Remember offset of next record within datagram. */
ssl->next_record_offset = rec.buf_len;
if( ssl->next_record_offset < ssl->in_left )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "more than one record within datagram" ) );
}
}
else
#endif
{
/*
* Fetch record contents from underlying transport.
*/
ret = mbedtls_ssl_fetch_input( ssl, rec.buf_len );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret );
return( ret );
}
ssl->in_left = 0;
}
/*
* Decrypt record contents.
*/
if( ( ret = ssl_prepare_record_content( ssl, &rec ) ) != 0 )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Silently discard invalid records */
if( ret == MBEDTLS_ERR_SSL_INVALID_MAC )
{
/* Except when waiting for Finished as a bad mac here
* probably means something went wrong in the handshake
* (eg wrong psk used, mitm downgrade attempt, etc.) */
if( ssl->state == MBEDTLS_SSL_CLIENT_FINISHED ||
ssl->state == MBEDTLS_SSL_SERVER_FINISHED )
{
#if defined(MBEDTLS_SSL_ALL_ALERT_MESSAGES)
if( ret == MBEDTLS_ERR_SSL_INVALID_MAC )
{
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC );
}
#endif
return( ret );
}
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
if( ssl->conf->badmac_limit != 0 &&
++ssl->badmac_seen >= ssl->conf->badmac_limit )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "too many records with bad MAC" ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
#endif
/* As above, invalid records cause
* dismissal of the whole datagram. */
ssl->next_record_offset = 0;
ssl->in_left = 0;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "discarding invalid record (mac)" ) );
return( MBEDTLS_ERR_SSL_CONTINUE_PROCESSING );
}
return( ret );
}
else
#endif
{
/* Error out (and send alert) on invalid records */
#if defined(MBEDTLS_SSL_ALL_ALERT_MESSAGES)
if( ret == MBEDTLS_ERR_SSL_INVALID_MAC )
{
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC );
}
#endif
return( ret );
}
}
/* Reset in pointers to default state for TLS/DTLS records,
* assuming no CID and no offset between record content and
* record plaintext. */
ssl_update_in_pointers( ssl );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->in_len = ssl->in_cid + rec.cid_len;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->in_iv = ssl->in_len + 2;
/* The record content type may change during decryption,
* so re-read it. */
ssl->in_msgtype = rec.type;
/* Also update the input buffer, because unfortunately
* the server-side ssl_parse_client_hello() reparses the
* record header when receiving a ClientHello initiating
* a renegotiation. */
ssl->in_hdr[0] = rec.type;
ssl->in_msg = rec.buf + rec.data_offset;
ssl->in_msglen = rec.data_len;
ssl->in_len[0] = (unsigned char)( rec.data_len >> 8 );
ssl->in_len[1] = (unsigned char)( rec.data_len );
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( ssl->transform_in != NULL &&
ssl->session_in->compression == MBEDTLS_SSL_COMPRESS_DEFLATE )
{
if( ( ret = ssl_decompress_buf( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_decompress_buf", ret );
return( ret );
}
/* Check actual (decompress) record content length against
* configured maximum. */
if( ssl->in_msglen > MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
return( 0 );
}
int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/*
* Handle particular types of records
*/
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE )
{
if( ( ret = mbedtls_ssl_prepare_handshake_record( ssl ) ) != 0 )
{
return( ret );
}
}
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC )
{
if( ssl->in_msglen != 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid CCS message, len: %d",
ssl->in_msglen ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
if( ssl->in_msg[0] != 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid CCS message, content: %02x",
ssl->in_msg[0] ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->state != MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC &&
ssl->state != MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC )
{
if( ssl->handshake == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping ChangeCipherSpec outside handshake" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "received out-of-order ChangeCipherSpec - remember" ) );
return( MBEDTLS_ERR_SSL_EARLY_MESSAGE );
}
#endif
}
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_ALERT )
{
if( ssl->in_msglen != 2 )
{
/* Note: Standard allows for more than one 2 byte alert
to be packed in a single message, but Mbed TLS doesn't
currently support this. */
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid alert message, len: %d",
ssl->in_msglen ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "got an alert message, type: [%d:%d]",
ssl->in_msg[0], ssl->in_msg[1] ) );
/*
* Ignore non-fatal alerts, except close_notify and no_renegotiation
*/
if( ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_FATAL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "is a fatal alert message (msg %d)",
ssl->in_msg[1] ) );
return( MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE );
}
if( ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "is a close notify message" ) );
return( MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY );
}
#if defined(MBEDTLS_SSL_RENEGOTIATION_ENABLED)
if( ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "is a SSLv3 no renegotiation alert" ) );
/* Will be handled when trying to parse ServerHello */
return( 0 );
}
#endif
#if defined(MBEDTLS_SSL_PROTO_SSL3) && defined(MBEDTLS_SSL_SRV_C)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 &&
ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == MBEDTLS_SSL_ALERT_MSG_NO_CERT )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "is a SSLv3 no_cert" ) );
/* Will be handled in mbedtls_ssl_parse_certificate() */
return( 0 );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 && MBEDTLS_SSL_SRV_C */
/* Silently ignore: fetch new message */
return MBEDTLS_ERR_SSL_NON_FATAL;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Drop unexpected ApplicationData records,
* except at the beginning of renegotiations */
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA &&
ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER
#if defined(MBEDTLS_SSL_RENEGOTIATION)
&& ! ( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->state == MBEDTLS_SSL_SERVER_HELLO )
#endif
)
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "dropping unexpected ApplicationData" ) );
return( MBEDTLS_ERR_SSL_NON_FATAL );
}
if( ssl->handshake != NULL &&
ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER )
{
ssl_handshake_wrapup_free_hs_transform( ssl );
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
return( 0 );
}
int mbedtls_ssl_send_fatal_handshake_failure( mbedtls_ssl_context *ssl )
{
return( mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ) );
}
int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
unsigned char level,
unsigned char message )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> send alert message" ) );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "send alert level=%u message=%u", level, message ));
ssl->out_msgtype = MBEDTLS_SSL_MSG_ALERT;
ssl->out_msglen = 2;
ssl->out_msg[0] = level;
ssl->out_msg[1] = message;
if( ( ret = mbedtls_ssl_write_record( ssl, SSL_FORCE_FLUSH ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= send alert message" ) );
return( 0 );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
static void ssl_clear_peer_cert( mbedtls_ssl_session *session )
{
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
if( session->peer_cert != NULL )
{
mbedtls_x509_crt_free( session->peer_cert );
mbedtls_free( session->peer_cert );
session->peer_cert = NULL;
}
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if( session->peer_cert_digest != NULL )
{
/* Zeroization is not necessary. */
mbedtls_free( session->peer_cert_digest );
session->peer_cert_digest = NULL;
session->peer_cert_digest_type = MBEDTLS_MD_NONE;
session->peer_cert_digest_len = 0;
}
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
/*
* Handshake functions
*/
#if !defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
/* No certificate support -> dummy functions */
int mbedtls_ssl_write_certificate( mbedtls_ssl_context *ssl )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( !mbedtls_ssl_ciphersuite_uses_srv_cert( ciphersuite_info ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( !mbedtls_ssl_ciphersuite_uses_srv_cert( ciphersuite_info ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#else /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
/* Some certificate support -> implement write and parse */
int mbedtls_ssl_write_certificate( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
size_t i, n;
const mbedtls_x509_crt *crt;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( !mbedtls_ssl_ciphersuite_uses_srv_cert( ciphersuite_info ) )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
{
if( ssl->client_auth == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
/*
* If using SSLv3 and got no cert, send an Alert message
* (otherwise an empty Certificate message will be sent).
*/
if( mbedtls_ssl_own_cert( ssl ) == NULL &&
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
ssl->out_msglen = 2;
ssl->out_msgtype = MBEDTLS_SSL_MSG_ALERT;
ssl->out_msg[0] = MBEDTLS_SSL_ALERT_LEVEL_WARNING;
ssl->out_msg[1] = MBEDTLS_SSL_ALERT_MSG_NO_CERT;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "got no certificate to send" ) );
goto write_msg;
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
}
#endif /* MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
{
if( mbedtls_ssl_own_cert( ssl ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no certificate to send" ) );
return( MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED );
}
}
#endif
MBEDTLS_SSL_DEBUG_CRT( 3, "own certificate", mbedtls_ssl_own_cert( ssl ) );
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 6 length of all certs
* 7 . 9 length of cert. 1
* 10 . n-1 peer certificate
* n . n+2 length of cert. 2
* n+3 . ... upper level cert, etc.
*/
i = 7;
crt = mbedtls_ssl_own_cert( ssl );
while( crt != NULL )
{
n = crt->raw.len;
if( n > MBEDTLS_SSL_OUT_CONTENT_LEN - 3 - i )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "certificate too large, %d > %d",
i + 3 + n, MBEDTLS_SSL_OUT_CONTENT_LEN ) );
return( MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE );
}
ssl->out_msg[i ] = (unsigned char)( n >> 16 );
ssl->out_msg[i + 1] = (unsigned char)( n >> 8 );
ssl->out_msg[i + 2] = (unsigned char)( n );
i += 3; memcpy( ssl->out_msg + i, crt->raw.p, n );
i += n; crt = crt->next;
}
ssl->out_msg[4] = (unsigned char)( ( i - 7 ) >> 16 );
ssl->out_msg[5] = (unsigned char)( ( i - 7 ) >> 8 );
ssl->out_msg[6] = (unsigned char)( ( i - 7 ) );
ssl->out_msglen = i;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CERTIFICATE;
#if defined(MBEDTLS_SSL_PROTO_SSL3) && defined(MBEDTLS_SSL_CLI_C)
write_msg:
#endif
ssl->state++;
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write certificate" ) );
return( ret );
}
#if defined(MBEDTLS_SSL_RENEGOTIATION) && defined(MBEDTLS_SSL_CLI_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
static int ssl_check_peer_crt_unchanged( mbedtls_ssl_context *ssl,
unsigned char *crt_buf,
size_t crt_buf_len )
{
mbedtls_x509_crt const * const peer_crt = ssl->session->peer_cert;
if( peer_crt == NULL )
return( -1 );
if( peer_crt->raw.len != crt_buf_len )
return( -1 );
return( memcmp( peer_crt->raw.p, crt_buf, peer_crt->raw.len ) );
}
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
static int ssl_check_peer_crt_unchanged( mbedtls_ssl_context *ssl,
unsigned char *crt_buf,
size_t crt_buf_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char const * const peer_cert_digest =
ssl->session->peer_cert_digest;
mbedtls_md_type_t const peer_cert_digest_type =
ssl->session->peer_cert_digest_type;
mbedtls_md_info_t const * const digest_info =
mbedtls_md_info_from_type( peer_cert_digest_type );
unsigned char tmp_digest[MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN];
size_t digest_len;
if( peer_cert_digest == NULL || digest_info == NULL )
return( -1 );
digest_len = mbedtls_md_get_size( digest_info );
if( digest_len > MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN )
return( -1 );
ret = mbedtls_md( digest_info, crt_buf, crt_buf_len, tmp_digest );
if( ret != 0 )
return( -1 );
return( memcmp( tmp_digest, peer_cert_digest, digest_len ) );
}
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_SSL_RENEGOTIATION && MBEDTLS_SSL_CLI_C */
/*
* Once the certificate message is read, parse it into a cert chain and
* perform basic checks, but leave actual verification to the caller
*/
static int ssl_parse_certificate_chain( mbedtls_ssl_context *ssl,
mbedtls_x509_crt *chain )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
#if defined(MBEDTLS_SSL_RENEGOTIATION) && defined(MBEDTLS_SSL_CLI_C)
int crt_cnt=0;
#endif
size_t i, n;
uint8_t alert;
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ssl->in_msg[0] != MBEDTLS_SSL_HS_CERTIFICATE ||
ssl->in_hslen < mbedtls_ssl_hs_hdr_len( ssl ) + 3 + 3 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
i = mbedtls_ssl_hs_hdr_len( ssl );
/*
* Same message structure as in mbedtls_ssl_write_certificate()
*/
n = ( ssl->in_msg[i+1] << 8 ) | ssl->in_msg[i+2];
if( ssl->in_msg[i] != 0 ||
ssl->in_hslen != n + 3 + mbedtls_ssl_hs_hdr_len( ssl ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
/* Make &ssl->in_msg[i] point to the beginning of the CRT chain. */
i += 3;
/* Iterate through and parse the CRTs in the provided chain. */
while( i < ssl->in_hslen )
{
/* Check that there's room for the next CRT's length fields. */
if ( i + 3 > ssl->in_hslen ) {
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
/* In theory, the CRT can be up to 2**24 Bytes, but we don't support
* anything beyond 2**16 ~ 64K. */
if( ssl->in_msg[i] != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
/* Read length of the next CRT in the chain. */
n = ( (unsigned int) ssl->in_msg[i + 1] << 8 )
| (unsigned int) ssl->in_msg[i + 2];
i += 3;
if( n < 128 || i + n > ssl->in_hslen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
/* Check if we're handling the first CRT in the chain. */
#if defined(MBEDTLS_SSL_RENEGOTIATION) && defined(MBEDTLS_SSL_CLI_C)
if( crt_cnt++ == 0 &&
ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT &&
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
{
/* During client-side renegotiation, check that the server's
* end-CRTs hasn't changed compared to the initial handshake,
* mitigating the triple handshake attack. On success, reuse
* the original end-CRT instead of parsing it again. */
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Check that peer CRT hasn't changed during renegotiation" ) );
if( ssl_check_peer_crt_unchanged( ssl,
&ssl->in_msg[i],
n ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "new server cert during renegotiation" ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
/* Now we can safely free the original chain. */
ssl_clear_peer_cert( ssl->session );
}
#endif /* MBEDTLS_SSL_RENEGOTIATION && MBEDTLS_SSL_CLI_C */
/* Parse the next certificate in the chain. */
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
ret = mbedtls_x509_crt_parse_der( chain, ssl->in_msg + i, n );
#else
/* If we don't need to store the CRT chain permanently, parse
* it in-place from the input buffer instead of making a copy. */
ret = mbedtls_x509_crt_parse_der_nocopy( chain, ssl->in_msg + i, n );
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
switch( ret )
{
case 0: /*ok*/
case MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG + MBEDTLS_ERR_OID_NOT_FOUND:
/* Ignore certificate with an unknown algorithm: maybe a
prior certificate was already trusted. */
break;
case MBEDTLS_ERR_X509_ALLOC_FAILED:
alert = MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR;
goto crt_parse_der_failed;
case MBEDTLS_ERR_X509_UNKNOWN_VERSION:
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
goto crt_parse_der_failed;
default:
alert = MBEDTLS_SSL_ALERT_MSG_BAD_CERT;
crt_parse_der_failed:
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, alert );
MBEDTLS_SSL_DEBUG_RET( 1, " mbedtls_x509_crt_parse_der", ret );
return( ret );
}
i += n;
}
MBEDTLS_SSL_DEBUG_CRT( 3, "peer certificate", chain );
return( 0 );
}
#if defined(MBEDTLS_SSL_SRV_C)
static int ssl_srv_check_client_no_crt_notification( mbedtls_ssl_context *ssl )
{
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
return( -1 );
#if defined(MBEDTLS_SSL_PROTO_SSL3)
/*
* Check if the client sent an empty certificate
*/
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
if( ssl->in_msglen == 2 &&
ssl->in_msgtype == MBEDTLS_SSL_MSG_ALERT &&
ssl->in_msg[0] == MBEDTLS_SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == MBEDTLS_SSL_ALERT_MSG_NO_CERT )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "SSLv3 client has no certificate" ) );
return( 0 );
}
return( -1 );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->in_hslen == 3 + mbedtls_ssl_hs_hdr_len( ssl ) &&
ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE &&
memcmp( ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ), "\0\0\0", 3 ) == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "TLSv1 client has no certificate" ) );
return( 0 );
}
return( -1 );
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
}
#endif /* MBEDTLS_SSL_SRV_C */
/* Check if a certificate message is expected.
* Return either
* - SSL_CERTIFICATE_EXPECTED, or
* - SSL_CERTIFICATE_SKIP
* indicating whether a Certificate message is expected or not.
*/
#define SSL_CERTIFICATE_EXPECTED 0
#define SSL_CERTIFICATE_SKIP 1
static int ssl_parse_certificate_coordinate( mbedtls_ssl_context *ssl,
int authmode )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
if( !mbedtls_ssl_ciphersuite_uses_srv_cert( ciphersuite_info ) )
return( SSL_CERTIFICATE_SKIP );
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
{
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
return( SSL_CERTIFICATE_SKIP );
if( authmode == MBEDTLS_SSL_VERIFY_NONE )
{
ssl->session_negotiate->verify_result =
MBEDTLS_X509_BADCERT_SKIP_VERIFY;
return( SSL_CERTIFICATE_SKIP );
}
}
#else
((void) authmode);
#endif /* MBEDTLS_SSL_SRV_C */
return( SSL_CERTIFICATE_EXPECTED );
}
static int ssl_parse_certificate_verify( mbedtls_ssl_context *ssl,
int authmode,
mbedtls_x509_crt *chain,
void *rs_ctx )
{
int ret = 0;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
int have_ca_chain = 0;
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
void *p_vrfy;
if( authmode == MBEDTLS_SSL_VERIFY_NONE )
return( 0 );
if( ssl->f_vrfy != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Use context-specific verification callback" ) );
f_vrfy = ssl->f_vrfy;
p_vrfy = ssl->p_vrfy;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Use configuration-specific verification callback" ) );
f_vrfy = ssl->conf->f_vrfy;
p_vrfy = ssl->conf->p_vrfy;
}
/*
* Main check: verify certificate
*/
#if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
if( ssl->conf->f_ca_cb != NULL )
{
((void) rs_ctx);
have_ca_chain = 1;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "use CA callback for X.509 CRT verification" ) );
ret = mbedtls_x509_crt_verify_with_ca_cb(
chain,
ssl->conf->f_ca_cb,
ssl->conf->p_ca_cb,
ssl->conf->cert_profile,
ssl->hostname,
&ssl->session_negotiate->verify_result,
f_vrfy, p_vrfy );
}
else
#endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
{
mbedtls_x509_crt *ca_chain;
mbedtls_x509_crl *ca_crl;
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
if( ssl->handshake->sni_ca_chain != NULL )
{
ca_chain = ssl->handshake->sni_ca_chain;
ca_crl = ssl->handshake->sni_ca_crl;
}
else
#endif
{
ca_chain = ssl->conf->ca_chain;
ca_crl = ssl->conf->ca_crl;
}
if( ca_chain != NULL )
have_ca_chain = 1;
ret = mbedtls_x509_crt_verify_restartable(
chain,
ca_chain, ca_crl,
ssl->conf->cert_profile,
ssl->hostname,
&ssl->session_negotiate->verify_result,
f_vrfy, p_vrfy, rs_ctx );
}
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "x509_verify_cert", ret );
}
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
return( MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS );
#endif
/*
* Secondary checks: always done, but change 'ret' only if it was 0
*/
#if defined(MBEDTLS_ECP_C)
{
const mbedtls_pk_context *pk = &chain->pk;
/* If certificate uses an EC key, make sure the curve is OK */
if( mbedtls_pk_can_do( pk, MBEDTLS_PK_ECKEY ) &&
mbedtls_ssl_check_curve( ssl, mbedtls_pk_ec( *pk )->grp.id ) != 0 )
{
ssl->session_negotiate->verify_result |= MBEDTLS_X509_BADCERT_BAD_KEY;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate (EC key curve)" ) );
if( ret == 0 )
ret = MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE;
}
}
#endif /* MBEDTLS_ECP_C */
if( mbedtls_ssl_check_cert_usage( chain,
ciphersuite_info,
! ssl->conf->endpoint,
&ssl->session_negotiate->verify_result ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate (usage extensions)" ) );
if( ret == 0 )
ret = MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE;
}
/* mbedtls_x509_crt_verify_with_profile is supposed to report a
* verification failure through MBEDTLS_ERR_X509_CERT_VERIFY_FAILED,
* with details encoded in the verification flags. All other kinds
* of error codes, including those from the user provided f_vrfy
* functions, are treated as fatal and lead to a failure of
* ssl_parse_certificate even if verification was optional. */
if( authmode == MBEDTLS_SSL_VERIFY_OPTIONAL &&
( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED ||
ret == MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE ) )
{
ret = 0;
}
if( have_ca_chain == 0 && authmode == MBEDTLS_SSL_VERIFY_REQUIRED )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no CA chain" ) );
ret = MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED;
}
if( ret != 0 )
{
uint8_t alert;
/* The certificate may have been rejected for several reasons.
Pick one and send the corresponding alert. Which alert to send
may be a subject of debate in some cases. */
if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_OTHER )
alert = MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_CN_MISMATCH )
alert = MBEDTLS_SSL_ALERT_MSG_BAD_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_KEY_USAGE )
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_EXT_KEY_USAGE )
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_NS_CERT_TYPE )
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_BAD_PK )
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_BAD_KEY )
alert = MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_EXPIRED )
alert = MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_REVOKED )
alert = MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED;
else if( ssl->session_negotiate->verify_result & MBEDTLS_X509_BADCERT_NOT_TRUSTED )
alert = MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA;
else
alert = MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN;
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
alert );
}
#if defined(MBEDTLS_DEBUG_C)
if( ssl->session_negotiate->verify_result != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "! Certificate verification flags %x",
ssl->session_negotiate->verify_result ) );
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Certificate verification flags clear" ) );
}
#endif /* MBEDTLS_DEBUG_C */
return( ret );
}
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
static int ssl_remember_peer_crt_digest( mbedtls_ssl_context *ssl,
unsigned char *start, size_t len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/* Remember digest of the peer's end-CRT. */
ssl->session_negotiate->peer_cert_digest =
mbedtls_calloc( 1, MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN );
if( ssl->session_negotiate->peer_cert_digest == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed",
MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
ret = mbedtls_md( mbedtls_md_info_from_type(
MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE ),
start, len,
ssl->session_negotiate->peer_cert_digest );
ssl->session_negotiate->peer_cert_digest_type =
MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE;
ssl->session_negotiate->peer_cert_digest_len =
MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN;
return( ret );
}
static int ssl_remember_peer_pubkey( mbedtls_ssl_context *ssl,
unsigned char *start, size_t len )
{
unsigned char *end = start + len;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/* Make a copy of the peer's raw public key. */
mbedtls_pk_init( &ssl->handshake->peer_pubkey );
ret = mbedtls_pk_parse_subpubkey( &start, end,
&ssl->handshake->peer_pubkey );
if( ret != 0 )
{
/* We should have parsed the public key before. */
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
return( 0 );
}
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl )
{
int ret = 0;
int crt_expected;
#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
const int authmode = ssl->handshake->sni_authmode != MBEDTLS_SSL_VERIFY_UNSET
? ssl->handshake->sni_authmode
: ssl->conf->authmode;
#else
const int authmode = ssl->conf->authmode;
#endif
void *rs_ctx = NULL;
mbedtls_x509_crt *chain = NULL;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
crt_expected = ssl_parse_certificate_coordinate( ssl, authmode );
if( crt_expected == SSL_CERTIFICATE_SKIP )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
goto exit;
}
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
if( ssl->handshake->ecrs_enabled &&
ssl->handshake->ecrs_state == ssl_ecrs_crt_verify )
{
chain = ssl->handshake->ecrs_peer_cert;
ssl->handshake->ecrs_peer_cert = NULL;
goto crt_verify;
}
#endif
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 )
{
/* mbedtls_ssl_read_record may have sent an alert already. We
let it decide whether to alert. */
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
goto exit;
}
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl_srv_check_client_no_crt_notification( ssl ) == 0 )
{
ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_MISSING;
if( authmode == MBEDTLS_SSL_VERIFY_OPTIONAL )
ret = 0;
else
ret = MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE;
goto exit;
}
#endif /* MBEDTLS_SSL_SRV_C */
/* Clear existing peer CRT structure in case we tried to
* reuse a session but it failed, and allocate a new one. */
ssl_clear_peer_cert( ssl->session_negotiate );
chain = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
if( chain == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed",
sizeof( mbedtls_x509_crt ) ) );
mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto exit;
}
mbedtls_x509_crt_init( chain );
ret = ssl_parse_certificate_chain( ssl, chain );
if( ret != 0 )
goto exit;
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
if( ssl->handshake->ecrs_enabled)
ssl->handshake->ecrs_state = ssl_ecrs_crt_verify;
crt_verify:
if( ssl->handshake->ecrs_enabled)
rs_ctx = &ssl->handshake->ecrs_ctx;
#endif
ret = ssl_parse_certificate_verify( ssl, authmode,
chain, rs_ctx );
if( ret != 0 )
goto exit;
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
{
unsigned char *crt_start, *pk_start;
size_t crt_len, pk_len;
/* We parse the CRT chain without copying, so
* these pointers point into the input buffer,
* and are hence still valid after freeing the
* CRT chain. */
crt_start = chain->raw.p;
crt_len = chain->raw.len;
pk_start = chain->pk_raw.p;
pk_len = chain->pk_raw.len;
/* Free the CRT structures before computing
* digest and copying the peer's public key. */
mbedtls_x509_crt_free( chain );
mbedtls_free( chain );
chain = NULL;
ret = ssl_remember_peer_crt_digest( ssl, crt_start, crt_len );
if( ret != 0 )
goto exit;
ret = ssl_remember_peer_pubkey( ssl, pk_start, pk_len );
if( ret != 0 )
goto exit;
}
#else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
/* Pass ownership to session structure. */
ssl->session_negotiate->peer_cert = chain;
chain = NULL;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate" ) );
exit:
if( ret == 0 )
ssl->state++;
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
if( ret == MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS )
{
ssl->handshake->ecrs_peer_cert = chain;
chain = NULL;
}
#endif
if( chain != NULL )
{
mbedtls_x509_crt_free( chain );
mbedtls_free( chain );
}
return( ret );
}
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
int mbedtls_ssl_write_change_cipher_spec( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write change cipher spec" ) );
ssl->out_msgtype = MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC;
ssl->out_msglen = 1;
ssl->out_msg[0] = 1;
ssl->state++;
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write change cipher spec" ) );
return( 0 );
}
int mbedtls_ssl_parse_change_cipher_spec( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse change cipher spec" ) );
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad change cipher spec message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/* CCS records are only accepted if they have length 1 and content '1',
* so we don't need to check this here. */
/*
* Switch to our negotiated transform and session parameters for inbound
* data.
*/
MBEDTLS_SSL_DEBUG_MSG( 3, ( "switching to new transform spec for inbound data" ) );
ssl->transform_in = ssl->transform_negotiate;
ssl->session_in = ssl->session_negotiate;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
ssl_dtls_replay_reset( ssl );
#endif
/* Increment epoch */
if( ++ssl->in_epoch == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "DTLS epoch would wrap" ) );
/* This is highly unlikely to happen for legitimate reasons, so
treat it as an attack and don't send an alert. */
return( MBEDTLS_ERR_SSL_COUNTER_WRAPPING );
}
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
memset( ssl->in_ctr, 0, 8 );
ssl_update_in_pointers( ssl );
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_activate != NULL )
{
if( ( ret = mbedtls_ssl_hw_record_activate( ssl, MBEDTLS_SSL_CHANNEL_INBOUND ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_activate", ret );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
ssl->state++;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse change cipher spec" ) );
return( 0 );
}
void mbedtls_ssl_optimize_checksum( mbedtls_ssl_context *ssl,
const mbedtls_ssl_ciphersuite_t *ciphersuite_info )
{
((void) ciphersuite_info);
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 )
ssl->handshake->update_checksum = ssl_update_checksum_md5sha1;
else
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA512_C)
if( ciphersuite_info->mac == MBEDTLS_MD_SHA384 )
ssl->handshake->update_checksum = ssl_update_checksum_sha384;
else
#endif
#if defined(MBEDTLS_SHA256_C)
if( ciphersuite_info->mac != MBEDTLS_MD_SHA384 )
ssl->handshake->update_checksum = ssl_update_checksum_sha256;
else
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return;
}
}
void mbedtls_ssl_reset_checksum( mbedtls_ssl_context *ssl )
{
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
mbedtls_md5_starts_ret( &ssl->handshake->fin_md5 );
mbedtls_sha1_starts_ret( &ssl->handshake->fin_sha1 );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_abort( &ssl->handshake->fin_sha256_psa );
psa_hash_setup( &ssl->handshake->fin_sha256_psa, PSA_ALG_SHA_256 );
#else
mbedtls_sha256_starts_ret( &ssl->handshake->fin_sha256, 0 );
#endif
#endif
#if defined(MBEDTLS_SHA512_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_abort( &ssl->handshake->fin_sha384_psa );
psa_hash_setup( &ssl->handshake->fin_sha384_psa, PSA_ALG_SHA_384 );
#else
mbedtls_sha512_starts_ret( &ssl->handshake->fin_sha512, 1 );
#endif
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
}
static void ssl_update_checksum_start( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
mbedtls_md5_update_ret( &ssl->handshake->fin_md5 , buf, len );
mbedtls_sha1_update_ret( &ssl->handshake->fin_sha1, buf, len );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_update( &ssl->handshake->fin_sha256_psa, buf, len );
#else
mbedtls_sha256_update_ret( &ssl->handshake->fin_sha256, buf, len );
#endif
#endif
#if defined(MBEDTLS_SHA512_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_update( &ssl->handshake->fin_sha384_psa, buf, len );
#else
mbedtls_sha512_update_ret( &ssl->handshake->fin_sha512, buf, len );
#endif
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
}
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
static void ssl_update_checksum_md5sha1( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
mbedtls_md5_update_ret( &ssl->handshake->fin_md5 , buf, len );
mbedtls_sha1_update_ret( &ssl->handshake->fin_sha1, buf, len );
}
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
static void ssl_update_checksum_sha256( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_update( &ssl->handshake->fin_sha256_psa, buf, len );
#else
mbedtls_sha256_update_ret( &ssl->handshake->fin_sha256, buf, len );
#endif
}
#endif
#if defined(MBEDTLS_SHA512_C)
static void ssl_update_checksum_sha384( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_update( &ssl->handshake->fin_sha384_psa, buf, len );
#else
mbedtls_sha512_update_ret( &ssl->handshake->fin_sha512, buf, len );
#endif
}
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_SSL_PROTO_SSL3)
static void ssl_calc_finished_ssl(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
const char *sender;
mbedtls_md5_context md5;
mbedtls_sha1_context sha1;
unsigned char padbuf[48];
unsigned char md5sum[16];
unsigned char sha1sum[20];
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc finished ssl" ) );
mbedtls_md5_init( &md5 );
mbedtls_sha1_init( &sha1 );
mbedtls_md5_clone( &md5, &ssl->handshake->fin_md5 );
mbedtls_sha1_clone( &sha1, &ssl->handshake->fin_sha1 );
/*
* SSLv3:
* hash =
* MD5( master + pad2 +
* MD5( handshake + sender + master + pad1 ) )
* + SHA1( master + pad2 +
* SHA1( handshake + sender + master + pad1 ) )
*/
#if !defined(MBEDTLS_MD5_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished md5 state", (unsigned char *)
md5.state, sizeof( md5.state ) );
#endif
#if !defined(MBEDTLS_SHA1_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished sha1 state", (unsigned char *)
sha1.state, sizeof( sha1.state ) );
#endif
sender = ( from == MBEDTLS_SSL_IS_CLIENT ) ? "CLNT"
: "SRVR";
memset( padbuf, 0x36, 48 );
mbedtls_md5_update_ret( &md5, (const unsigned char *) sender, 4 );
mbedtls_md5_update_ret( &md5, session->master, 48 );
mbedtls_md5_update_ret( &md5, padbuf, 48 );
mbedtls_md5_finish_ret( &md5, md5sum );
mbedtls_sha1_update_ret( &sha1, (const unsigned char *) sender, 4 );
mbedtls_sha1_update_ret( &sha1, session->master, 48 );
mbedtls_sha1_update_ret( &sha1, padbuf, 40 );
mbedtls_sha1_finish_ret( &sha1, sha1sum );
memset( padbuf, 0x5C, 48 );
mbedtls_md5_starts_ret( &md5 );
mbedtls_md5_update_ret( &md5, session->master, 48 );
mbedtls_md5_update_ret( &md5, padbuf, 48 );
mbedtls_md5_update_ret( &md5, md5sum, 16 );
mbedtls_md5_finish_ret( &md5, buf );
mbedtls_sha1_starts_ret( &sha1 );
mbedtls_sha1_update_ret( &sha1, session->master, 48 );
mbedtls_sha1_update_ret( &sha1, padbuf , 40 );
mbedtls_sha1_update_ret( &sha1, sha1sum, 20 );
mbedtls_sha1_finish_ret( &sha1, buf + 16 );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, 36 );
mbedtls_md5_free( &md5 );
mbedtls_sha1_free( &sha1 );
mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) );
mbedtls_platform_zeroize( md5sum, sizeof( md5sum ) );
mbedtls_platform_zeroize( sha1sum, sizeof( sha1sum ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
static void ssl_calc_finished_tls(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
mbedtls_md5_context md5;
mbedtls_sha1_context sha1;
unsigned char padbuf[36];
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc finished tls" ) );
mbedtls_md5_init( &md5 );
mbedtls_sha1_init( &sha1 );
mbedtls_md5_clone( &md5, &ssl->handshake->fin_md5 );
mbedtls_sha1_clone( &sha1, &ssl->handshake->fin_sha1 );
/*
* TLSv1:
* hash = PRF( master, finished_label,
* MD5( handshake ) + SHA1( handshake ) )[0..11]
*/
#if !defined(MBEDTLS_MD5_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished md5 state", (unsigned char *)
md5.state, sizeof( md5.state ) );
#endif
#if !defined(MBEDTLS_SHA1_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished sha1 state", (unsigned char *)
sha1.state, sizeof( sha1.state ) );
#endif
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
mbedtls_md5_finish_ret( &md5, padbuf );
mbedtls_sha1_finish_ret( &sha1, padbuf + 16 );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 36, buf, len );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
mbedtls_md5_free( &md5 );
mbedtls_sha1_free( &sha1 );
mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
static void ssl_calc_finished_tls_sha256(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
unsigned char padbuf[32];
#if defined(MBEDTLS_USE_PSA_CRYPTO)
size_t hash_size;
psa_hash_operation_t sha256_psa = PSA_HASH_OPERATION_INIT;
psa_status_t status;
#else
mbedtls_sha256_context sha256;
#endif
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
#if defined(MBEDTLS_USE_PSA_CRYPTO)
sha256_psa = psa_hash_operation_init();
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc PSA finished tls sha256" ) );
status = psa_hash_clone( &ssl->handshake->fin_sha256_psa, &sha256_psa );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash clone failed" ) );
return;
}
status = psa_hash_finish( &sha256_psa, padbuf, sizeof( padbuf ), &hash_size );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash finish failed" ) );
return;
}
MBEDTLS_SSL_DEBUG_BUF( 3, "PSA calculated padbuf", padbuf, 32 );
#else
mbedtls_sha256_init( &sha256 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc finished tls sha256" ) );
mbedtls_sha256_clone( &sha256, &ssl->handshake->fin_sha256 );
/*
* TLSv1.2:
* hash = PRF( master, finished_label,
* Hash( handshake ) )[0.11]
*/
#if !defined(MBEDTLS_SHA256_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished sha2 state", (unsigned char *)
sha256.state, sizeof( sha256.state ) );
#endif
mbedtls_sha256_finish_ret( &sha256, padbuf );
mbedtls_sha256_free( &sha256 );
#endif /* MBEDTLS_USE_PSA_CRYPTO */
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 32, buf, len );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
static void ssl_calc_finished_tls_sha384(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
unsigned char padbuf[48];
#if defined(MBEDTLS_USE_PSA_CRYPTO)
size_t hash_size;
psa_hash_operation_t sha384_psa = PSA_HASH_OPERATION_INIT;
psa_status_t status;
#else
mbedtls_sha512_context sha512;
#endif
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
#if defined(MBEDTLS_USE_PSA_CRYPTO)
sha384_psa = psa_hash_operation_init();
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc PSA finished tls sha384" ) );
status = psa_hash_clone( &ssl->handshake->fin_sha384_psa, &sha384_psa );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash clone failed" ) );
return;
}
status = psa_hash_finish( &sha384_psa, padbuf, sizeof( padbuf ), &hash_size );
if( status != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "PSA hash finish failed" ) );
return;
}
MBEDTLS_SSL_DEBUG_BUF( 3, "PSA calculated padbuf", padbuf, 48 );
#else
mbedtls_sha512_init( &sha512 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> calc finished tls sha384" ) );
mbedtls_sha512_clone( &sha512, &ssl->handshake->fin_sha512 );
/*
* TLSv1.2:
* hash = PRF( master, finished_label,
* Hash( handshake ) )[0.11]
*/
#if !defined(MBEDTLS_SHA512_ALT)
MBEDTLS_SSL_DEBUG_BUF( 4, "finished sha512 state", (unsigned char *)
sha512.state, sizeof( sha512.state ) );
#endif
mbedtls_sha512_finish_ret( &sha512, padbuf );
mbedtls_sha512_free( &sha512 );
#endif
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 48, buf, len );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* MBEDTLS_SHA512_C */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
static void ssl_handshake_wrapup_free_hs_transform( mbedtls_ssl_context *ssl )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "=> handshake wrapup: final free" ) );
/*
* Free our handshake params
*/
mbedtls_ssl_handshake_free( ssl );
mbedtls_free( ssl->handshake );
ssl->handshake = NULL;
/*
* Free the previous transform and swith in the current one
*/
if( ssl->transform )
{
mbedtls_ssl_transform_free( ssl->transform );
mbedtls_free( ssl->transform );
}
ssl->transform = ssl->transform_negotiate;
ssl->transform_negotiate = NULL;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "<= handshake wrapup: final free" ) );
}
void mbedtls_ssl_handshake_wrapup( mbedtls_ssl_context *ssl )
{
int resume = ssl->handshake->resume;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "=> handshake wrapup" ) );
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
{
ssl->renego_status = MBEDTLS_SSL_RENEGOTIATION_DONE;
ssl->renego_records_seen = 0;
}
#endif
/*
* Free the previous session and switch in the current one
*/
if( ssl->session )
{
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
/* RFC 7366 3.1: keep the EtM state */
ssl->session_negotiate->encrypt_then_mac =
ssl->session->encrypt_then_mac;
#endif
mbedtls_ssl_session_free( ssl->session );
mbedtls_free( ssl->session );
}
ssl->session = ssl->session_negotiate;
ssl->session_negotiate = NULL;
/*
* Add cache entry
*/
if( ssl->conf->f_set_cache != NULL &&
ssl->session->id_len != 0 &&
resume == 0 )
{
if( ssl->conf->f_set_cache( ssl->conf->p_cache, ssl->session ) != 0 )
MBEDTLS_SSL_DEBUG_MSG( 1, ( "cache did not store session" ) );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->flight != NULL )
{
/* Cancel handshake timer */
ssl_set_timer( ssl, 0 );
/* Keep last flight around in case we need to resend it:
* we need the handshake and transform structures for that */
MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip freeing handshake and transform" ) );
}
else
#endif
ssl_handshake_wrapup_free_hs_transform( ssl );
ssl->state++;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "<= handshake wrapup" ) );
}
int mbedtls_ssl_write_finished( mbedtls_ssl_context *ssl )
{
int ret, hash_len;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write finished" ) );
ssl_update_out_pointers( ssl, ssl->transform_negotiate );
ssl->handshake->calc_finished( ssl, ssl->out_msg + 4, ssl->conf->endpoint );
/*
* RFC 5246 7.4.9 (Page 63) says 12 is the default length and ciphersuites
* may define some other value. Currently (early 2016), no defined
* ciphersuite does this (and this is unlikely to change as activity has
* moved to TLS 1.3 now) so we can keep the hardcoded 12 here.
*/
hash_len = ( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ) ? 36 : 12;
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->verify_data_len = hash_len;
memcpy( ssl->own_verify_data, ssl->out_msg + 4, hash_len );
#endif
ssl->out_msglen = 4 + hash_len;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_FINISHED;
/*
* In case of session resuming, invert the client and server
* ChangeCipherSpec messages order.
*/
if( ssl->handshake->resume != 0 )
{
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
ssl->state = MBEDTLS_SSL_HANDSHAKE_WRAPUP;
#endif
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
ssl->state = MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC;
#endif
}
else
ssl->state++;
/*
* Switch to our negotiated transform and session parameters for outbound
* data.
*/
MBEDTLS_SSL_DEBUG_MSG( 3, ( "switching to new transform spec for outbound data" ) );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
unsigned char i;
/* Remember current epoch settings for resending */
ssl->handshake->alt_transform_out = ssl->transform_out;
memcpy( ssl->handshake->alt_out_ctr, ssl->cur_out_ctr, 8 );
/* Set sequence_number to zero */
memset( ssl->cur_out_ctr + 2, 0, 6 );
/* Increment epoch */
for( i = 2; i > 0; i-- )
if( ++ssl->cur_out_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "DTLS epoch would wrap" ) );
return( MBEDTLS_ERR_SSL_COUNTER_WRAPPING );
}
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
memset( ssl->cur_out_ctr, 0, 8 );
ssl->transform_out = ssl->transform_negotiate;
ssl->session_out = ssl->session_negotiate;
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_activate != NULL )
{
if( ( ret = mbedtls_ssl_hw_record_activate( ssl, MBEDTLS_SSL_CHANNEL_OUTBOUND ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_activate", ret );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
mbedtls_ssl_send_flight_completed( ssl );
#endif
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret );
return( ret );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flight_transmit", ret );
return( ret );
}
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write finished" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
#define SSL_MAX_HASH_LEN 36
#else
#define SSL_MAX_HASH_LEN 12
#endif
int mbedtls_ssl_parse_finished( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned int hash_len;
unsigned char buf[SSL_MAX_HASH_LEN];
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse finished" ) );
ssl->handshake->calc_finished( ssl, buf, ssl->conf->endpoint ^ 1 );
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/* There is currently no ciphersuite using another length with TLS 1.2 */
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
hash_len = 36;
else
#endif
hash_len = 12;
if( ssl->in_msg[0] != MBEDTLS_SSL_HS_FINISHED ||
ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) + hash_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_FINISHED );
}
if( mbedtls_ssl_safer_memcmp( ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ),
buf, hash_len ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
return( MBEDTLS_ERR_SSL_BAD_HS_FINISHED );
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->verify_data_len = hash_len;
memcpy( ssl->peer_verify_data, buf, hash_len );
#endif
if( ssl->handshake->resume != 0 )
{
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
ssl->state = MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC;
#endif
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
ssl->state = MBEDTLS_SSL_HANDSHAKE_WRAPUP;
#endif
}
else
ssl->state++;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
mbedtls_ssl_recv_flight_completed( ssl );
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse finished" ) );
return( 0 );
}
static void ssl_handshake_params_init( mbedtls_ssl_handshake_params *handshake )
{
memset( handshake, 0, sizeof( mbedtls_ssl_handshake_params ) );
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
mbedtls_md5_init( &handshake->fin_md5 );
mbedtls_sha1_init( &handshake->fin_sha1 );
mbedtls_md5_starts_ret( &handshake->fin_md5 );
mbedtls_sha1_starts_ret( &handshake->fin_sha1 );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
handshake->fin_sha256_psa = psa_hash_operation_init();
psa_hash_setup( &handshake->fin_sha256_psa, PSA_ALG_SHA_256 );
#else
mbedtls_sha256_init( &handshake->fin_sha256 );
mbedtls_sha256_starts_ret( &handshake->fin_sha256, 0 );
#endif
#endif
#if defined(MBEDTLS_SHA512_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
handshake->fin_sha384_psa = psa_hash_operation_init();
psa_hash_setup( &handshake->fin_sha384_psa, PSA_ALG_SHA_384 );
#else
mbedtls_sha512_init( &handshake->fin_sha512 );
mbedtls_sha512_starts_ret( &handshake->fin_sha512, 1 );
#endif
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
handshake->update_checksum = ssl_update_checksum_start;
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
mbedtls_ssl_sig_hash_set_init( &handshake->hash_algs );
#endif
#if defined(MBEDTLS_DHM_C)
mbedtls_dhm_init( &handshake->dhm_ctx );
#endif
#if defined(MBEDTLS_ECDH_C)
mbedtls_ecdh_init( &handshake->ecdh_ctx );
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
mbedtls_ecjpake_init( &handshake->ecjpake_ctx );
#if defined(MBEDTLS_SSL_CLI_C)
handshake->ecjpake_cache = NULL;
handshake->ecjpake_cache_len = 0;
#endif
#endif
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
mbedtls_x509_crt_restart_init( &handshake->ecrs_ctx );
#endif
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
handshake->sni_authmode = MBEDTLS_SSL_VERIFY_UNSET;
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C) && \
!defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
mbedtls_pk_init( &handshake->peer_pubkey );
#endif
}
void mbedtls_ssl_transform_init( mbedtls_ssl_transform *transform )
{
memset( transform, 0, sizeof(mbedtls_ssl_transform) );
mbedtls_cipher_init( &transform->cipher_ctx_enc );
mbedtls_cipher_init( &transform->cipher_ctx_dec );
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
mbedtls_md_init( &transform->md_ctx_enc );
mbedtls_md_init( &transform->md_ctx_dec );
#endif
}
void mbedtls_ssl_session_init( mbedtls_ssl_session *session )
{
memset( session, 0, sizeof(mbedtls_ssl_session) );
}
static int ssl_handshake_init( mbedtls_ssl_context *ssl )
{
/* Clear old handshake information if present */
if( ssl->transform_negotiate )
mbedtls_ssl_transform_free( ssl->transform_negotiate );
if( ssl->session_negotiate )
mbedtls_ssl_session_free( ssl->session_negotiate );
if( ssl->handshake )
mbedtls_ssl_handshake_free( ssl );
/*
* Either the pointers are now NULL or cleared properly and can be freed.
* Now allocate missing structures.
*/
if( ssl->transform_negotiate == NULL )
{
ssl->transform_negotiate = mbedtls_calloc( 1, sizeof(mbedtls_ssl_transform) );
}
if( ssl->session_negotiate == NULL )
{
ssl->session_negotiate = mbedtls_calloc( 1, sizeof(mbedtls_ssl_session) );
}
if( ssl->handshake == NULL )
{
ssl->handshake = mbedtls_calloc( 1, sizeof(mbedtls_ssl_handshake_params) );
}
/* All pointers should exist and can be directly freed without issue */
if( ssl->handshake == NULL ||
ssl->transform_negotiate == NULL ||
ssl->session_negotiate == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc() of ssl sub-contexts failed" ) );
mbedtls_free( ssl->handshake );
mbedtls_free( ssl->transform_negotiate );
mbedtls_free( ssl->session_negotiate );
ssl->handshake = NULL;
ssl->transform_negotiate = NULL;
ssl->session_negotiate = NULL;
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
/* Initialize structures */
mbedtls_ssl_session_init( ssl->session_negotiate );
mbedtls_ssl_transform_init( ssl->transform_negotiate );
ssl_handshake_params_init( ssl->handshake );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->handshake->alt_transform_out = ssl->transform_out;
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_PREPARING;
else
ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_WAITING;
ssl_set_timer( ssl, 0 );
}
#endif
return( 0 );
}
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
/* Dummy cookie callbacks for defaults */
static int ssl_cookie_write_dummy( void *ctx,
unsigned char **p, unsigned char *end,
const unsigned char *cli_id, size_t cli_id_len )
{
((void) ctx);
((void) p);
((void) end);
((void) cli_id);
((void) cli_id_len);
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
static int ssl_cookie_check_dummy( void *ctx,
const unsigned char *cookie, size_t cookie_len,
const unsigned char *cli_id, size_t cli_id_len )
{
((void) ctx);
((void) cookie);
((void) cookie_len);
((void) cli_id);
((void) cli_id_len);
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
/* Once ssl->out_hdr as the address of the beginning of the
* next outgoing record is set, deduce the other pointers.
*
* Note: For TLS, we save the implicit record sequence number
* (entering MAC computation) in the 8 bytes before ssl->out_hdr,
* and the caller has to make sure there's space for this.
*/
static void ssl_update_out_pointers( mbedtls_ssl_context *ssl,
mbedtls_ssl_transform *transform )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->out_ctr = ssl->out_hdr + 3;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->out_cid = ssl->out_ctr + 8;
ssl->out_len = ssl->out_cid;
if( transform != NULL )
ssl->out_len += transform->out_cid_len;
#else /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->out_len = ssl->out_ctr + 8;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->out_iv = ssl->out_len + 2;
}
else
#endif
{
ssl->out_ctr = ssl->out_hdr - 8;
ssl->out_len = ssl->out_hdr + 3;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->out_cid = ssl->out_len;
#endif
ssl->out_iv = ssl->out_hdr + 5;
}
/* Adjust out_msg to make space for explicit IV, if used. */
if( transform != NULL &&
ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
ssl->out_msg = ssl->out_iv + transform->ivlen - transform->fixed_ivlen;
}
else
ssl->out_msg = ssl->out_iv;
}
/* Once ssl->in_hdr as the address of the beginning of the
* next incoming record is set, deduce the other pointers.
*
* Note: For TLS, we save the implicit record sequence number
* (entering MAC computation) in the 8 bytes before ssl->in_hdr,
* and the caller has to make sure there's space for this.
*/
static void ssl_update_in_pointers( mbedtls_ssl_context *ssl )
{
/* This function sets the pointers to match the case
* of unprotected TLS/DTLS records, with both ssl->in_iv
* and ssl->in_msg pointing to the beginning of the record
* content.
*
* When decrypting a protected record, ssl->in_msg
* will be shifted to point to the beginning of the
* record plaintext.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* This sets the header pointers to match records
* without CID. When we receive a record containing
* a CID, the fields are shifted accordingly in
* ssl_parse_record_header(). */
ssl->in_ctr = ssl->in_hdr + 3;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->in_cid = ssl->in_ctr + 8;
ssl->in_len = ssl->in_cid; /* Default: no CID */
#else /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->in_len = ssl->in_ctr + 8;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
ssl->in_iv = ssl->in_len + 2;
}
else
#endif
{
ssl->in_ctr = ssl->in_hdr - 8;
ssl->in_len = ssl->in_hdr + 3;
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
ssl->in_cid = ssl->in_len;
#endif
ssl->in_iv = ssl->in_hdr + 5;
}
/* This will be adjusted at record decryption time. */
ssl->in_msg = ssl->in_iv;
}
/*
* Initialize an SSL context
*/
void mbedtls_ssl_init( mbedtls_ssl_context *ssl )
{
memset( ssl, 0, sizeof( mbedtls_ssl_context ) );
}
/*
* Setup an SSL context
*/
static void ssl_reset_in_out_pointers( mbedtls_ssl_context *ssl )
{
/* Set the incoming and outgoing record pointers. */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->out_hdr = ssl->out_buf;
ssl->in_hdr = ssl->in_buf;
}
else
#endif /* MBEDTLS_SSL_PROTO_DTLS */
{
ssl->out_hdr = ssl->out_buf + 8;
ssl->in_hdr = ssl->in_buf + 8;
}
/* Derive other internal pointers. */
ssl_update_out_pointers( ssl, NULL /* no transform enabled */ );
ssl_update_in_pointers ( ssl );
}
int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
const mbedtls_ssl_config *conf )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
ssl->conf = conf;
/*
* Prepare base structures
*/
/* Set to NULL in case of an error condition */
ssl->out_buf = NULL;
ssl->in_buf = mbedtls_calloc( 1, MBEDTLS_SSL_IN_BUFFER_LEN );
if( ssl->in_buf == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed", MBEDTLS_SSL_IN_BUFFER_LEN) );
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto error;
}
ssl->out_buf = mbedtls_calloc( 1, MBEDTLS_SSL_OUT_BUFFER_LEN );
if( ssl->out_buf == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed", MBEDTLS_SSL_OUT_BUFFER_LEN) );
ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
goto error;
}
ssl_reset_in_out_pointers( ssl );
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
goto error;
return( 0 );
error:
mbedtls_free( ssl->in_buf );
mbedtls_free( ssl->out_buf );
ssl->conf = NULL;
ssl->in_buf = NULL;
ssl->out_buf = NULL;
ssl->in_hdr = NULL;
ssl->in_ctr = NULL;
ssl->in_len = NULL;
ssl->in_iv = NULL;
ssl->in_msg = NULL;
ssl->out_hdr = NULL;
ssl->out_ctr = NULL;
ssl->out_len = NULL;
ssl->out_iv = NULL;
ssl->out_msg = NULL;
return( ret );
}
/*
* Reset an initialized and used SSL context for re-use while retaining
* all application-set variables, function pointers and data.
*
* If partial is non-zero, keep data in the input buffer and client ID.
* (Use when a DTLS client reconnects from the same port.)
*/
static int ssl_session_reset_int( mbedtls_ssl_context *ssl, int partial )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
#if !defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) || \
!defined(MBEDTLS_SSL_SRV_C)
((void) partial);
#endif
ssl->state = MBEDTLS_SSL_HELLO_REQUEST;
/* Cancel any possibly running timer */
ssl_set_timer( ssl, 0 );
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->renego_status = MBEDTLS_SSL_INITIAL_HANDSHAKE;
ssl->renego_records_seen = 0;
ssl->verify_data_len = 0;
memset( ssl->own_verify_data, 0, MBEDTLS_SSL_VERIFY_DATA_MAX_LEN );
memset( ssl->peer_verify_data, 0, MBEDTLS_SSL_VERIFY_DATA_MAX_LEN );
#endif
ssl->secure_renegotiation = MBEDTLS_SSL_LEGACY_RENEGOTIATION;
ssl->in_offt = NULL;
ssl_reset_in_out_pointers( ssl );
ssl->in_msgtype = 0;
ssl->in_msglen = 0;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
ssl->next_record_offset = 0;
ssl->in_epoch = 0;
#endif
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
ssl_dtls_replay_reset( ssl );
#endif
ssl->in_hslen = 0;
ssl->nb_zero = 0;
ssl->keep_current_message = 0;
ssl->out_msgtype = 0;
ssl->out_msglen = 0;
ssl->out_left = 0;
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
if( ssl->split_done != MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED )
ssl->split_done = 0;
#endif
memset( ssl->cur_out_ctr, 0, sizeof( ssl->cur_out_ctr ) );
ssl->transform_in = NULL;
ssl->transform_out = NULL;
ssl->session_in = NULL;
ssl->session_out = NULL;
memset( ssl->out_buf, 0, MBEDTLS_SSL_OUT_BUFFER_LEN );
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) && defined(MBEDTLS_SSL_SRV_C)
if( partial == 0 )
#endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE && MBEDTLS_SSL_SRV_C */
{
ssl->in_left = 0;
memset( ssl->in_buf, 0, MBEDTLS_SSL_IN_BUFFER_LEN );
}
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_reset != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_reset()" ) );
if( ( ret = mbedtls_ssl_hw_record_reset( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_hw_record_reset", ret );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
if( ssl->transform )
{
mbedtls_ssl_transform_free( ssl->transform );
mbedtls_free( ssl->transform );
ssl->transform = NULL;
}
if( ssl->session )
{
mbedtls_ssl_session_free( ssl->session );
mbedtls_free( ssl->session );
ssl->session = NULL;
}
#if defined(MBEDTLS_SSL_ALPN)
ssl->alpn_chosen = NULL;
#endif
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE)
if( partial == 0 )
#endif
{
mbedtls_free( ssl->cli_id );
ssl->cli_id = NULL;
ssl->cli_id_len = 0;
}
#endif
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
return( ret );
return( 0 );
}
/*
* Reset an initialized and used SSL context for re-use while retaining
* all application-set variables, function pointers and data.
*/
int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl )
{
return( ssl_session_reset_int( ssl, 0 ) );
}
/*
* SSL set accessors
*/
void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint )
{
conf->endpoint = endpoint;
}
void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport )
{
conf->transport = transport;
}
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode )
{
conf->anti_replay = mode;
}
#endif
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit )
{
conf->badmac_limit = limit;
}
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
unsigned allow_packing )
{
ssl->disable_datagram_packing = !allow_packing;
}
void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf,
uint32_t min, uint32_t max )
{
conf->hs_timeout_min = min;
conf->hs_timeout_max = max;
}
#endif
void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode )
{
conf->authmode = authmode;
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf,
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
void *p_vrfy )
{
conf->f_vrfy = f_vrfy;
conf->p_vrfy = p_vrfy;
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
conf->f_rng = f_rng;
conf->p_rng = p_rng;
}
void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf,
void (*f_dbg)(void *, int, const char *, int, const char *),
void *p_dbg )
{
conf->f_dbg = f_dbg;
conf->p_dbg = p_dbg;
}
void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl,
void *p_bio,
mbedtls_ssl_send_t *f_send,
mbedtls_ssl_recv_t *f_recv,
mbedtls_ssl_recv_timeout_t *f_recv_timeout )
{
ssl->p_bio = p_bio;
ssl->f_send = f_send;
ssl->f_recv = f_recv;
ssl->f_recv_timeout = f_recv_timeout;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu )
{
ssl->mtu = mtu;
}
#endif
void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout )
{
conf->read_timeout = timeout;
}
void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl,
void *p_timer,
mbedtls_ssl_set_timer_t *f_set_timer,
mbedtls_ssl_get_timer_t *f_get_timer )
{
ssl->p_timer = p_timer;
ssl->f_set_timer = f_set_timer;
ssl->f_get_timer = f_get_timer;
/* Make sure we start with no timer running */
ssl_set_timer( ssl, 0 );
}
#if defined(MBEDTLS_SSL_SRV_C)
void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf,
void *p_cache,
int (*f_get_cache)(void *, mbedtls_ssl_session *),
int (*f_set_cache)(void *, const mbedtls_ssl_session *) )
{
conf->p_cache = p_cache;
conf->f_get_cache = f_get_cache;
conf->f_set_cache = f_set_cache;
}
#endif /* MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_SSL_CLI_C)
int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ssl == NULL ||
session == NULL ||
ssl->session_negotiate == NULL ||
ssl->conf->endpoint != MBEDTLS_SSL_IS_CLIENT )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
if( ( ret = mbedtls_ssl_session_copy( ssl->session_negotiate,
session ) ) != 0 )
return( ret );
ssl->handshake->resume = 1;
return( 0 );
}
#endif /* MBEDTLS_SSL_CLI_C */
void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
const int *ciphersuites )
{
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_0] = ciphersuites;
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_1] = ciphersuites;
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_2] = ciphersuites;
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_3] = ciphersuites;
}
void mbedtls_ssl_conf_ciphersuites_for_version( mbedtls_ssl_config *conf,
const int *ciphersuites,
int major, int minor )
{
if( major != MBEDTLS_SSL_MAJOR_VERSION_3 )
return;
if( minor < MBEDTLS_SSL_MINOR_VERSION_0 || minor > MBEDTLS_SSL_MINOR_VERSION_3 )
return;
conf->ciphersuite_list[minor] = ciphersuites;
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf,
const mbedtls_x509_crt_profile *profile )
{
conf->cert_profile = profile;
}
/* Append a new keycert entry to a (possibly empty) list */
static int ssl_append_key_cert( mbedtls_ssl_key_cert **head,
mbedtls_x509_crt *cert,
mbedtls_pk_context *key )
{
mbedtls_ssl_key_cert *new_cert;
new_cert = mbedtls_calloc( 1, sizeof( mbedtls_ssl_key_cert ) );
if( new_cert == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
new_cert->cert = cert;
new_cert->key = key;
new_cert->next = NULL;
/* Update head is the list was null, else add to the end */
if( *head == NULL )
{
*head = new_cert;
}
else
{
mbedtls_ssl_key_cert *cur = *head;
while( cur->next != NULL )
cur = cur->next;
cur->next = new_cert;
}
return( 0 );
}
int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf,
mbedtls_x509_crt *own_cert,
mbedtls_pk_context *pk_key )
{
return( ssl_append_key_cert( &conf->key_cert, own_cert, pk_key ) );
}
void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
mbedtls_x509_crt *ca_chain,
mbedtls_x509_crl *ca_crl )
{
conf->ca_chain = ca_chain;
conf->ca_crl = ca_crl;
#if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
/* mbedtls_ssl_conf_ca_chain() and mbedtls_ssl_conf_ca_cb()
* cannot be used together. */
conf->f_ca_cb = NULL;
conf->p_ca_cb = NULL;
#endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
}
#if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
void mbedtls_ssl_conf_ca_cb( mbedtls_ssl_config *conf,
mbedtls_x509_crt_ca_cb_t f_ca_cb,
void *p_ca_cb )
{
conf->f_ca_cb = f_ca_cb;
conf->p_ca_cb = p_ca_cb;
/* mbedtls_ssl_conf_ca_chain() and mbedtls_ssl_conf_ca_cb()
* cannot be used together. */
conf->ca_chain = NULL;
conf->ca_crl = NULL;
}
#endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl,
mbedtls_x509_crt *own_cert,
mbedtls_pk_context *pk_key )
{
return( ssl_append_key_cert( &ssl->handshake->sni_key_cert,
own_cert, pk_key ) );
}
void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl,
mbedtls_x509_crt *ca_chain,
mbedtls_x509_crl *ca_crl )
{
ssl->handshake->sni_ca_chain = ca_chain;
ssl->handshake->sni_ca_crl = ca_crl;
}
void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl,
int authmode )
{
ssl->handshake->sni_authmode = authmode;
}
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
void mbedtls_ssl_set_verify( mbedtls_ssl_context *ssl,
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
void *p_vrfy )
{
ssl->f_vrfy = f_vrfy;
ssl->p_vrfy = p_vrfy;
}
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
/*
* Set EC J-PAKE password for current handshake
*/
int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl,
const unsigned char *pw,
size_t pw_len )
{
mbedtls_ecjpake_role role;
if( ssl->handshake == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
role = MBEDTLS_ECJPAKE_SERVER;
else
role = MBEDTLS_ECJPAKE_CLIENT;
return( mbedtls_ecjpake_setup( &ssl->handshake->ecjpake_ctx,
role,
MBEDTLS_MD_SHA256,
MBEDTLS_ECP_DP_SECP256R1,
pw, pw_len ) );
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
static void ssl_conf_remove_psk( mbedtls_ssl_config *conf )
{
/* Remove reference to existing PSK, if any. */
#if defined(MBEDTLS_USE_PSA_CRYPTO)
if( conf->psk_opaque != 0 )
{
/* The maintenance of the PSK key slot is the
* user's responsibility. */
conf->psk_opaque = 0;
}
/* This and the following branch should never
* be taken simultaenously as we maintain the
* invariant that raw and opaque PSKs are never
* configured simultaneously. As a safeguard,
* though, `else` is omitted here. */
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if( conf->psk != NULL )
{
mbedtls_platform_zeroize( conf->psk, conf->psk_len );
mbedtls_free( conf->psk );
conf->psk = NULL;
conf->psk_len = 0;
}
/* Remove reference to PSK identity, if any. */
if( conf->psk_identity != NULL )
{
mbedtls_free( conf->psk_identity );
conf->psk_identity = NULL;
conf->psk_identity_len = 0;
}
}
/* This function assumes that PSK identity in the SSL config is unset.
* It checks that the provided identity is well-formed and attempts
* to make a copy of it in the SSL config.
* On failure, the PSK identity in the config remains unset. */
static int ssl_conf_set_psk_identity( mbedtls_ssl_config *conf,
unsigned char const *psk_identity,
size_t psk_identity_len )
{
/* Identity len will be encoded on two bytes */
if( psk_identity == NULL ||
( psk_identity_len >> 16 ) != 0 ||
psk_identity_len > MBEDTLS_SSL_OUT_CONTENT_LEN )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
conf->psk_identity = mbedtls_calloc( 1, psk_identity_len );
if( conf->psk_identity == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
conf->psk_identity_len = psk_identity_len;
memcpy( conf->psk_identity, psk_identity, conf->psk_identity_len );
return( 0 );
}
int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf,
const unsigned char *psk, size_t psk_len,
const unsigned char *psk_identity, size_t psk_identity_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/* Remove opaque/raw PSK + PSK Identity */
ssl_conf_remove_psk( conf );
/* Check and set raw PSK */
if( psk == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( psk_len == 0 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( psk_len > MBEDTLS_PSK_MAX_LEN )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( ( conf->psk = mbedtls_calloc( 1, psk_len ) ) == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
conf->psk_len = psk_len;
memcpy( conf->psk, psk, conf->psk_len );
/* Check and set PSK Identity */
ret = ssl_conf_set_psk_identity( conf, psk_identity, psk_identity_len );
if( ret != 0 )
ssl_conf_remove_psk( conf );
return( ret );
}
static void ssl_remove_psk( mbedtls_ssl_context *ssl )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
if( ssl->handshake->psk_opaque != 0 )
{
ssl->handshake->psk_opaque = 0;
}
else
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if( ssl->handshake->psk != NULL )
{
mbedtls_platform_zeroize( ssl->handshake->psk,
ssl->handshake->psk_len );
mbedtls_free( ssl->handshake->psk );
ssl->handshake->psk_len = 0;
}
}
int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
const unsigned char *psk, size_t psk_len )
{
if( psk == NULL || ssl->handshake == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( psk_len > MBEDTLS_PSK_MAX_LEN )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl_remove_psk( ssl );
if( ( ssl->handshake->psk = mbedtls_calloc( 1, psk_len ) ) == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
ssl->handshake->psk_len = psk_len;
memcpy( ssl->handshake->psk, psk, ssl->handshake->psk_len );
return( 0 );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
int mbedtls_ssl_conf_psk_opaque( mbedtls_ssl_config *conf,
psa_key_handle_t psk_slot,
const unsigned char *psk_identity,
size_t psk_identity_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/* Clear opaque/raw PSK + PSK Identity, if present. */
ssl_conf_remove_psk( conf );
/* Check and set opaque PSK */
if( psk_slot == 0 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
conf->psk_opaque = psk_slot;
/* Check and set PSK Identity */
ret = ssl_conf_set_psk_identity( conf, psk_identity,
psk_identity_len );
if( ret != 0 )
ssl_conf_remove_psk( conf );
return( ret );
}
int mbedtls_ssl_set_hs_psk_opaque( mbedtls_ssl_context *ssl,
psa_key_handle_t psk_slot )
{
if( psk_slot == 0 || ssl->handshake == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl_remove_psk( ssl );
ssl->handshake->psk_opaque = psk_slot;
return( 0 );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf,
int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
size_t),
void *p_psk )
{
conf->f_psk = f_psk;
conf->p_psk = p_psk;
}
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
#if !defined(MBEDTLS_DEPRECATED_REMOVED)
int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf, const char *dhm_P, const char *dhm_G )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ( ret = mbedtls_mpi_read_string( &conf->dhm_P, 16, dhm_P ) ) != 0 ||
( ret = mbedtls_mpi_read_string( &conf->dhm_G, 16, dhm_G ) ) != 0 )
{
mbedtls_mpi_free( &conf->dhm_P );
mbedtls_mpi_free( &conf->dhm_G );
return( ret );
}
return( 0 );
}
#endif /* MBEDTLS_DEPRECATED_REMOVED */
int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
const unsigned char *dhm_P, size_t P_len,
const unsigned char *dhm_G, size_t G_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ( ret = mbedtls_mpi_read_binary( &conf->dhm_P, dhm_P, P_len ) ) != 0 ||
( ret = mbedtls_mpi_read_binary( &conf->dhm_G, dhm_G, G_len ) ) != 0 )
{
mbedtls_mpi_free( &conf->dhm_P );
mbedtls_mpi_free( &conf->dhm_G );
return( ret );
}
return( 0 );
}
int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ( ret = mbedtls_mpi_copy( &conf->dhm_P, &dhm_ctx->P ) ) != 0 ||
( ret = mbedtls_mpi_copy( &conf->dhm_G, &dhm_ctx->G ) ) != 0 )
{
mbedtls_mpi_free( &conf->dhm_P );
mbedtls_mpi_free( &conf->dhm_G );
return( ret );
}
return( 0 );
}
#endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
/*
* Set the minimum length for Diffie-Hellman parameters
*/
void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf,
unsigned int bitlen )
{
conf->dhm_min_bitlen = bitlen;
}
#endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
/*
* Set allowed/preferred hashes for handshake signatures
*/
void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
const int *hashes )
{
conf->sig_hashes = hashes;
}
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_ECP_C)
/*
* Set the allowed elliptic curves
*/
void mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf,
const mbedtls_ecp_group_id *curve_list )
{
conf->curve_list = curve_list;
}
#endif /* MBEDTLS_ECP_C */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname )
{
/* Initialize to suppress unnecessary compiler warning */
size_t hostname_len = 0;
/* Check if new hostname is valid before
* making any change to current one */
if( hostname != NULL )
{
hostname_len = strlen( hostname );
if( hostname_len > MBEDTLS_SSL_MAX_HOST_NAME_LEN )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Now it's clear that we will overwrite the old hostname,
* so we can free it safely */
if( ssl->hostname != NULL )
{
mbedtls_platform_zeroize( ssl->hostname, strlen( ssl->hostname ) );
mbedtls_free( ssl->hostname );
}
/* Passing NULL as hostname shall clear the old one */
if( hostname == NULL )
{
ssl->hostname = NULL;
}
else
{
ssl->hostname = mbedtls_calloc( 1, hostname_len + 1 );
if( ssl->hostname == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( ssl->hostname, hostname, hostname_len );
ssl->hostname[hostname_len] = '\0';
}
return( 0 );
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf,
int (*f_sni)(void *, mbedtls_ssl_context *,
const unsigned char *, size_t),
void *p_sni )
{
conf->f_sni = f_sni;
conf->p_sni = p_sni;
}
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_SSL_ALPN)
int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos )
{
size_t cur_len, tot_len;
const char **p;
/*
* RFC 7301 3.1: "Empty strings MUST NOT be included and byte strings
* MUST NOT be truncated."
* We check lengths now rather than later.
*/
tot_len = 0;
for( p = protos; *p != NULL; p++ )
{
cur_len = strlen( *p );
tot_len += cur_len;
if( cur_len == 0 || cur_len > 255 || tot_len > 65535 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
conf->alpn_list = protos;
return( 0 );
}
const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl )
{
return( ssl->alpn_chosen );
}
#endif /* MBEDTLS_SSL_ALPN */
void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor )
{
conf->max_major_ver = major;
conf->max_minor_ver = minor;
}
void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor )
{
conf->min_major_ver = major;
conf->min_minor_ver = minor;
}
#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
void mbedtls_ssl_conf_fallback( mbedtls_ssl_config *conf, char fallback )
{
conf->fallback = fallback;
}
#endif
#if defined(MBEDTLS_SSL_SRV_C)
void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
char cert_req_ca_list )
{
conf->cert_req_ca_list = cert_req_ca_list;
}
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm )
{
conf->encrypt_then_mac = etm;
}
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems )
{
conf->extended_ms = ems;
}
#endif
#if defined(MBEDTLS_ARC4_C)
void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 )
{
conf->arc4_disabled = arc4;
}
#endif
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code )
{
if( mfl_code >= MBEDTLS_SSL_MAX_FRAG_LEN_INVALID ||
ssl_mfl_code_to_length( mfl_code ) > MBEDTLS_TLS_EXT_ADV_CONTENT_LEN )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
conf->mfl_code = mfl_code;
return( 0 );
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate )
{
conf->trunc_hmac = truncate;
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
void mbedtls_ssl_conf_cbc_record_splitting( mbedtls_ssl_config *conf, char split )
{
conf->cbc_record_splitting = split;
}
#endif
void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy )
{
conf->allow_legacy_renegotiation = allow_legacy;
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation )
{
conf->disable_renegotiation = renegotiation;
}
void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records )
{
conf->renego_max_records = max_records;
}
void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
const unsigned char period[8] )
{
memcpy( conf->renego_period, period, 8 );
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
#if defined(MBEDTLS_SSL_CLI_C)
void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets )
{
conf->session_tickets = use_tickets;
}
#endif
#if defined(MBEDTLS_SSL_SRV_C)
void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf,
mbedtls_ssl_ticket_write_t *f_ticket_write,
mbedtls_ssl_ticket_parse_t *f_ticket_parse,
void *p_ticket )
{
conf->f_ticket_write = f_ticket_write;
conf->f_ticket_parse = f_ticket_parse;
conf->p_ticket = p_ticket;
}
#endif
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_SSL_EXPORT_KEYS)
void mbedtls_ssl_conf_export_keys_cb( mbedtls_ssl_config *conf,
mbedtls_ssl_export_keys_t *f_export_keys,
void *p_export_keys )
{
conf->f_export_keys = f_export_keys;
conf->p_export_keys = p_export_keys;
}
void mbedtls_ssl_conf_export_keys_ext_cb( mbedtls_ssl_config *conf,
mbedtls_ssl_export_keys_ext_t *f_export_keys_ext,
void *p_export_keys )
{
conf->f_export_keys_ext = f_export_keys_ext;
conf->p_export_keys = p_export_keys;
}
#endif
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
void mbedtls_ssl_conf_async_private_cb(
mbedtls_ssl_config *conf,
mbedtls_ssl_async_sign_t *f_async_sign,
mbedtls_ssl_async_decrypt_t *f_async_decrypt,
mbedtls_ssl_async_resume_t *f_async_resume,
mbedtls_ssl_async_cancel_t *f_async_cancel,
void *async_config_data )
{
conf->f_async_sign_start = f_async_sign;
conf->f_async_decrypt_start = f_async_decrypt;
conf->f_async_resume = f_async_resume;
conf->f_async_cancel = f_async_cancel;
conf->p_async_config_data = async_config_data;
}
void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf )
{
return( conf->p_async_config_data );
}
void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl )
{
if( ssl->handshake == NULL )
return( NULL );
else
return( ssl->handshake->user_async_ctx );
}
void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
void *ctx )
{
if( ssl->handshake != NULL )
ssl->handshake->user_async_ctx = ctx;
}
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
/*
* SSL get accessors
*/
size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl )
{
return( ssl->in_offt == NULL ? 0 : ssl->in_msglen );
}
int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl )
{
/*
* Case A: We're currently holding back
* a message for further processing.
*/
if( ssl->keep_current_message == 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: record held back for processing" ) );
return( 1 );
}
/*
* Case B: Further records are pending in the current datagram.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->in_left > ssl->next_record_offset )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: more records within current datagram" ) );
return( 1 );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/*
* Case C: A handshake message is being processed.
*/
if( ssl->in_hslen > 0 && ssl->in_hslen < ssl->in_msglen )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: more handshake messages within current record" ) );
return( 1 );
}
/*
* Case D: An application data message is being processed
*/
if( ssl->in_offt != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: application data record is being processed" ) );
return( 1 );
}
/*
* In all other cases, the rest of the message can be dropped.
* As in ssl_get_next_record, this needs to be adapted if
* we implement support for multiple alerts in single records.
*/
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_check_pending: nothing pending" ) );
return( 0 );
}
uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl )
{
if( ssl->session != NULL )
return( ssl->session->verify_result );
if( ssl->session_negotiate != NULL )
return( ssl->session_negotiate->verify_result );
return( 0xFFFFFFFF );
}
const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl )
{
if( ssl == NULL || ssl->session == NULL )
return( NULL );
return mbedtls_ssl_get_ciphersuite_name( ssl->session->ciphersuite );
}
const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
switch( ssl->minor_ver )
{
case MBEDTLS_SSL_MINOR_VERSION_2:
return( "DTLSv1.0" );
case MBEDTLS_SSL_MINOR_VERSION_3:
return( "DTLSv1.2" );
default:
return( "unknown (DTLS)" );
}
}
#endif
switch( ssl->minor_ver )
{
case MBEDTLS_SSL_MINOR_VERSION_0:
return( "SSLv3.0" );
case MBEDTLS_SSL_MINOR_VERSION_1:
return( "TLSv1.0" );
case MBEDTLS_SSL_MINOR_VERSION_2:
return( "TLSv1.1" );
case MBEDTLS_SSL_MINOR_VERSION_3:
return( "TLSv1.2" );
default:
return( "unknown" );
}
}
int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl )
{
size_t transform_expansion = 0;
const mbedtls_ssl_transform *transform = ssl->transform_out;
unsigned block_size;
size_t out_hdr_len = mbedtls_ssl_out_hdr_len( ssl );
if( transform == NULL )
return( (int) out_hdr_len );
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( ssl->session_out->compression != MBEDTLS_SSL_COMPRESS_NULL )
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
switch( mbedtls_cipher_get_cipher_mode( &transform->cipher_ctx_enc ) )
{
case MBEDTLS_MODE_GCM:
case MBEDTLS_MODE_CCM:
case MBEDTLS_MODE_CHACHAPOLY:
case MBEDTLS_MODE_STREAM:
transform_expansion = transform->minlen;
break;
case MBEDTLS_MODE_CBC:
block_size = mbedtls_cipher_get_block_size(
&transform->cipher_ctx_enc );
/* Expansion due to the addition of the MAC. */
transform_expansion += transform->maclen;
/* Expansion due to the addition of CBC padding;
* Theoretically up to 256 bytes, but we never use
* more than the block size of the underlying cipher. */
transform_expansion += block_size;
/* For TLS 1.1 or higher, an explicit IV is added
* after the record header. */
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
transform_expansion += block_size;
#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
break;
default:
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( transform->out_cid_len != 0 )
transform_expansion += MBEDTLS_SSL_MAX_CID_EXPANSION;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
return( (int)( out_hdr_len + transform_expansion ) );
}
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl )
{
size_t max_len;
/*
* Assume mfl_code is correct since it was checked when set
*/
max_len = ssl_mfl_code_to_length( ssl->conf->mfl_code );
/* Check if a smaller max length was negotiated */
if( ssl->session_out != NULL &&
ssl_mfl_code_to_length( ssl->session_out->mfl_code ) < max_len )
{
max_len = ssl_mfl_code_to_length( ssl->session_out->mfl_code );
}
/* During a handshake, use the value being negotiated */
if( ssl->session_negotiate != NULL &&
ssl_mfl_code_to_length( ssl->session_negotiate->mfl_code ) < max_len )
{
max_len = ssl_mfl_code_to_length( ssl->session_negotiate->mfl_code );
}
return( max_len );
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static size_t ssl_get_current_mtu( const mbedtls_ssl_context *ssl )
{
/* Return unlimited mtu for client hello messages to avoid fragmentation. */
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT &&
( ssl->state == MBEDTLS_SSL_CLIENT_HELLO ||
ssl->state == MBEDTLS_SSL_SERVER_HELLO ) )
return ( 0 );
if( ssl->handshake == NULL || ssl->handshake->mtu == 0 )
return( ssl->mtu );
if( ssl->mtu == 0 )
return( ssl->handshake->mtu );
return( ssl->mtu < ssl->handshake->mtu ?
ssl->mtu : ssl->handshake->mtu );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl )
{
size_t max_len = MBEDTLS_SSL_OUT_CONTENT_LEN;
#if !defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) && \
!defined(MBEDTLS_SSL_PROTO_DTLS)
(void) ssl;
#endif
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
const size_t mfl = mbedtls_ssl_get_max_frag_len( ssl );
if( max_len > mfl )
max_len = mfl;
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl_get_current_mtu( ssl ) != 0 )
{
const size_t mtu = ssl_get_current_mtu( ssl );
const int ret = mbedtls_ssl_get_record_expansion( ssl );
const size_t overhead = (size_t) ret;
if( ret < 0 )
return( ret );
if( mtu <= overhead )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "MTU too low for record expansion" ) );
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
if( max_len > mtu - overhead )
max_len = mtu - overhead;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if !defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) && \
!defined(MBEDTLS_SSL_PROTO_DTLS)
((void) ssl);
#endif
return( (int) max_len );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl )
{
if( ssl == NULL || ssl->session == NULL )
return( NULL );
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
return( ssl->session->peer_cert );
#else
return( NULL );
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_CLI_C)
int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl,
mbedtls_ssl_session *dst )
{
if( ssl == NULL ||
dst == NULL ||
ssl->session == NULL ||
ssl->conf->endpoint != MBEDTLS_SSL_IS_CLIENT )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
return( mbedtls_ssl_session_copy( dst, ssl->session ) );
}
#endif /* MBEDTLS_SSL_CLI_C */
const mbedtls_ssl_session *mbedtls_ssl_get_session_pointer( const mbedtls_ssl_context *ssl )
{
if( ssl == NULL )
return( NULL );
return( ssl->session );
}
/*
* Define ticket header determining Mbed TLS version
* and structure of the ticket.
*/
/*
* Define bitflag determining compile-time settings influencing
* structure of serialized SSL sessions.
*/
#if defined(MBEDTLS_HAVE_TIME)
#define SSL_SERIALIZED_SESSION_CONFIG_TIME 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_TIME 0
#endif /* MBEDTLS_HAVE_TIME */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#define SSL_SERIALIZED_SESSION_CONFIG_CRT 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_CRT 0
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_CLI_C) && defined(MBEDTLS_SSL_SESSION_TICKETS)
#define SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET 0
#endif /* MBEDTLS_SSL_CLI_C && MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
#define SSL_SERIALIZED_SESSION_CONFIG_MFL 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_MFL 0
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
#define SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC 0
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
#define SSL_SERIALIZED_SESSION_CONFIG_ETM 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_ETM 0
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
#define SSL_SERIALIZED_SESSION_CONFIG_TICKET 1
#else
#define SSL_SERIALIZED_SESSION_CONFIG_TICKET 0
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#define SSL_SERIALIZED_SESSION_CONFIG_TIME_BIT 0
#define SSL_SERIALIZED_SESSION_CONFIG_CRT_BIT 1
#define SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET_BIT 2
#define SSL_SERIALIZED_SESSION_CONFIG_MFL_BIT 3
#define SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC_BIT 4
#define SSL_SERIALIZED_SESSION_CONFIG_ETM_BIT 5
#define SSL_SERIALIZED_SESSION_CONFIG_TICKET_BIT 6
#define SSL_SERIALIZED_SESSION_CONFIG_BITFLAG \
( (uint16_t) ( \
( SSL_SERIALIZED_SESSION_CONFIG_TIME << SSL_SERIALIZED_SESSION_CONFIG_TIME_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_CRT << SSL_SERIALIZED_SESSION_CONFIG_CRT_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET << SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_MFL << SSL_SERIALIZED_SESSION_CONFIG_MFL_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC << SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_ETM << SSL_SERIALIZED_SESSION_CONFIG_ETM_BIT ) | \
( SSL_SERIALIZED_SESSION_CONFIG_TICKET << SSL_SERIALIZED_SESSION_CONFIG_TICKET_BIT ) ) )
static unsigned char ssl_serialized_session_header[] = {
MBEDTLS_VERSION_MAJOR,
MBEDTLS_VERSION_MINOR,
MBEDTLS_VERSION_PATCH,
( SSL_SERIALIZED_SESSION_CONFIG_BITFLAG >> 8 ) & 0xFF,
( SSL_SERIALIZED_SESSION_CONFIG_BITFLAG >> 0 ) & 0xFF,
};
/*
* Serialize a session in the following format:
* (in the presentation language of TLS, RFC 8446 section 3)
*
* opaque mbedtls_version[3]; // major, minor, patch
* opaque session_format[2]; // version-specific 16-bit field determining
* // the format of the remaining
* // serialized data.
*
* Note: When updating the format, remember to keep
* these version+format bytes.
*
* // In this version, `session_format` determines
* // the setting of those compile-time
* // configuration options which influence
* // the structure of mbedtls_ssl_session.
* uint64 start_time;
* uint8 ciphersuite[2]; // defined by the standard
* uint8 compression; // 0 or 1
* uint8 session_id_len; // at most 32
* opaque session_id[32];
* opaque master[48]; // fixed length in the standard
* uint32 verify_result;
* opaque peer_cert<0..2^24-1>; // length 0 means no peer cert
* opaque ticket<0..2^24-1>; // length 0 means no ticket
* uint32 ticket_lifetime;
* uint8 mfl_code; // up to 255 according to standard
* uint8 trunc_hmac; // 0 or 1
* uint8 encrypt_then_mac; // 0 or 1
*
* The order is the same as in the definition of the structure, except
* verify_result is put before peer_cert so that all mandatory fields come
* together in one block.
*/
static int ssl_session_save( const mbedtls_ssl_session *session,
unsigned char omit_header,
unsigned char *buf,
size_t buf_len,
size_t *olen )
{
unsigned char *p = buf;
size_t used = 0;
#if defined(MBEDTLS_HAVE_TIME)
uint64_t start;
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
size_t cert_len;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
if( !omit_header )
{
/*
* Add version identifier
*/
used += sizeof( ssl_serialized_session_header );
if( used <= buf_len )
{
memcpy( p, ssl_serialized_session_header,
sizeof( ssl_serialized_session_header ) );
p += sizeof( ssl_serialized_session_header );
}
}
/*
* Time
*/
#if defined(MBEDTLS_HAVE_TIME)
used += 8;
if( used <= buf_len )
{
start = (uint64_t) session->start;
*p++ = (unsigned char)( ( start >> 56 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 48 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 40 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 32 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( start >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( start ) & 0xFF );
}
#endif /* MBEDTLS_HAVE_TIME */
/*
* Basic mandatory fields
*/
used += 2 /* ciphersuite */
+ 1 /* compression */
+ 1 /* id_len */
+ sizeof( session->id )
+ sizeof( session->master )
+ 4; /* verify_result */
if( used <= buf_len )
{
*p++ = (unsigned char)( ( session->ciphersuite >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( session->ciphersuite ) & 0xFF );
*p++ = (unsigned char)( session->compression & 0xFF );
*p++ = (unsigned char)( session->id_len & 0xFF );
memcpy( p, session->id, 32 );
p += 32;
memcpy( p, session->master, 48 );
p += 48;
*p++ = (unsigned char)( ( session->verify_result >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( session->verify_result >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( session->verify_result >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( session->verify_result ) & 0xFF );
}
/*
* Peer's end-entity certificate
*/
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
if( session->peer_cert == NULL )
cert_len = 0;
else
cert_len = session->peer_cert->raw.len;
used += 3 + cert_len;
if( used <= buf_len )
{
*p++ = (unsigned char)( ( cert_len >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( cert_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( cert_len ) & 0xFF );
if( session->peer_cert != NULL )
{
memcpy( p, session->peer_cert->raw.p, cert_len );
p += cert_len;
}
}
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if( session->peer_cert_digest != NULL )
{
used += 1 /* type */ + 1 /* length */ + session->peer_cert_digest_len;
if( used <= buf_len )
{
*p++ = (unsigned char) session->peer_cert_digest_type;
*p++ = (unsigned char) session->peer_cert_digest_len;
memcpy( p, session->peer_cert_digest,
session->peer_cert_digest_len );
p += session->peer_cert_digest_len;
}
}
else
{
used += 2;
if( used <= buf_len )
{
*p++ = (unsigned char) MBEDTLS_MD_NONE;
*p++ = 0;
}
}
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
/*
* Session ticket if any, plus associated data
*/
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
used += 3 + session->ticket_len + 4; /* len + ticket + lifetime */
if( used <= buf_len )
{
*p++ = (unsigned char)( ( session->ticket_len >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( session->ticket_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( session->ticket_len ) & 0xFF );
if( session->ticket != NULL )
{
memcpy( p, session->ticket, session->ticket_len );
p += session->ticket_len;
}
*p++ = (unsigned char)( ( session->ticket_lifetime >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( session->ticket_lifetime >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( session->ticket_lifetime >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( session->ticket_lifetime ) & 0xFF );
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
/*
* Misc extension-related info
*/
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
used += 1;
if( used <= buf_len )
*p++ = session->mfl_code;
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
used += 1;
if( used <= buf_len )
*p++ = (unsigned char)( ( session->trunc_hmac ) & 0xFF );
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
used += 1;
if( used <= buf_len )
*p++ = (unsigned char)( ( session->encrypt_then_mac ) & 0xFF );
#endif
/* Done */
*olen = used;
if( used > buf_len )
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
return( 0 );
}
/*
* Public wrapper for ssl_session_save()
*/
int mbedtls_ssl_session_save( const mbedtls_ssl_session *session,
unsigned char *buf,
size_t buf_len,
size_t *olen )
{
return( ssl_session_save( session, 0, buf, buf_len, olen ) );
}
/*
* Deserialize session, see mbedtls_ssl_session_save() for format.
*
* This internal version is wrapped by a public function that cleans up in
* case of error, and has an extra option omit_header.
*/
static int ssl_session_load( mbedtls_ssl_session *session,
unsigned char omit_header,
const unsigned char *buf,
size_t len )
{
const unsigned char *p = buf;
const unsigned char * const end = buf + len;
#if defined(MBEDTLS_HAVE_TIME)
uint64_t start;
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
size_t cert_len;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
if( !omit_header )
{
/*
* Check version identifier
*/
if( (size_t)( end - p ) < sizeof( ssl_serialized_session_header ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( memcmp( p, ssl_serialized_session_header,
sizeof( ssl_serialized_session_header ) ) != 0 )
{
return( MBEDTLS_ERR_SSL_VERSION_MISMATCH );
}
p += sizeof( ssl_serialized_session_header );
}
/*
* Time
*/
#if defined(MBEDTLS_HAVE_TIME)
if( 8 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
start = ( (uint64_t) p[0] << 56 ) |
( (uint64_t) p[1] << 48 ) |
( (uint64_t) p[2] << 40 ) |
( (uint64_t) p[3] << 32 ) |
( (uint64_t) p[4] << 24 ) |
( (uint64_t) p[5] << 16 ) |
( (uint64_t) p[6] << 8 ) |
( (uint64_t) p[7] );
p += 8;
session->start = (time_t) start;
#endif /* MBEDTLS_HAVE_TIME */
/*
* Basic mandatory fields
*/
if( 2 + 1 + 1 + 32 + 48 + 4 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->ciphersuite = ( p[0] << 8 ) | p[1];
p += 2;
session->compression = *p++;
session->id_len = *p++;
memcpy( session->id, p, 32 );
p += 32;
memcpy( session->master, p, 48 );
p += 48;
session->verify_result = ( (uint32_t) p[0] << 24 ) |
( (uint32_t) p[1] << 16 ) |
( (uint32_t) p[2] << 8 ) |
( (uint32_t) p[3] );
p += 4;
/* Immediately clear invalid pointer values that have been read, in case
* we exit early before we replaced them with valid ones. */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
session->peer_cert = NULL;
#else
session->peer_cert_digest = NULL;
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
session->ticket = NULL;
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
/*
* Peer certificate
*/
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
/* Deserialize CRT from the end of the ticket. */
if( 3 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
cert_len = ( p[0] << 16 ) | ( p[1] << 8 ) | p[2];
p += 3;
if( cert_len != 0 )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( cert_len > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->peer_cert = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
if( session->peer_cert == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
mbedtls_x509_crt_init( session->peer_cert );
if( ( ret = mbedtls_x509_crt_parse_der( session->peer_cert,
p, cert_len ) ) != 0 )
{
mbedtls_x509_crt_free( session->peer_cert );
mbedtls_free( session->peer_cert );
session->peer_cert = NULL;
return( ret );
}
p += cert_len;
}
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
/* Deserialize CRT digest from the end of the ticket. */
if( 2 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->peer_cert_digest_type = (mbedtls_md_type_t) *p++;
session->peer_cert_digest_len = (size_t) *p++;
if( session->peer_cert_digest_len != 0 )
{
const mbedtls_md_info_t *md_info =
mbedtls_md_info_from_type( session->peer_cert_digest_type );
if( md_info == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( session->peer_cert_digest_len != mbedtls_md_get_size( md_info ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( session->peer_cert_digest_len > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->peer_cert_digest =
mbedtls_calloc( 1, session->peer_cert_digest_len );
if( session->peer_cert_digest == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( session->peer_cert_digest, p,
session->peer_cert_digest_len );
p += session->peer_cert_digest_len;
}
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
/*
* Session ticket and associated data
*/
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
if( 3 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->ticket_len = ( p[0] << 16 ) | ( p[1] << 8 ) | p[2];
p += 3;
if( session->ticket_len != 0 )
{
if( session->ticket_len > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->ticket = mbedtls_calloc( 1, session->ticket_len );
if( session->ticket == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( session->ticket, p, session->ticket_len );
p += session->ticket_len;
}
if( 4 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->ticket_lifetime = ( (uint32_t) p[0] << 24 ) |
( (uint32_t) p[1] << 16 ) |
( (uint32_t) p[2] << 8 ) |
( (uint32_t) p[3] );
p += 4;
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
/*
* Misc extension-related info
*/
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
if( 1 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->mfl_code = *p++;
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
if( 1 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->trunc_hmac = *p++;
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if( 1 > (size_t)( end - p ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session->encrypt_then_mac = *p++;
#endif
/* Done, should have consumed entire buffer */
if( p != end )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
return( 0 );
}
/*
* Deserialize session: public wrapper for error cleaning
*/
int mbedtls_ssl_session_load( mbedtls_ssl_session *session,
const unsigned char *buf,
size_t len )
{
int ret = ssl_session_load( session, 0, buf, len );
if( ret != 0 )
mbedtls_ssl_session_free( session );
return( ret );
}
/*
* Perform a single step of the SSL handshake
*/
int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
ret = mbedtls_ssl_handshake_client_step( ssl );
#endif
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
ret = mbedtls_ssl_handshake_server_step( ssl );
#endif
return( ret );
}
/*
* Perform the SSL handshake
*/
int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl )
{
int ret = 0;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> handshake" ) );
while( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
ret = mbedtls_ssl_handshake_step( ssl );
if( ret != 0 )
break;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= handshake" ) );
return( ret );
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
#if defined(MBEDTLS_SSL_SRV_C)
/*
* Write HelloRequest to request renegotiation on server
*/
static int ssl_write_hello_request( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write hello request" ) );
ssl->out_msglen = 4;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_HELLO_REQUEST;
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write hello request" ) );
return( 0 );
}
#endif /* MBEDTLS_SSL_SRV_C */
/*
* Actually renegotiate current connection, triggered by either:
* - any side: calling mbedtls_ssl_renegotiate(),
* - client: receiving a HelloRequest during mbedtls_ssl_read(),
* - server: receiving any handshake message on server during mbedtls_ssl_read() after
* the initial handshake is completed.
* If the handshake doesn't complete due to waiting for I/O, it will continue
* during the next calls to mbedtls_ssl_renegotiate() or mbedtls_ssl_read() respectively.
*/
static int ssl_start_renegotiation( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> renegotiate" ) );
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
return( ret );
/* RFC 6347 4.2.2: "[...] the HelloRequest will have message_seq = 0 and
* the ServerHello will have message_seq = 1" */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING )
{
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
ssl->handshake->out_msg_seq = 1;
else
ssl->handshake->in_msg_seq = 1;
}
#endif
ssl->state = MBEDTLS_SSL_HELLO_REQUEST;
ssl->renego_status = MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS;
if( ( ret = mbedtls_ssl_handshake( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_handshake", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= renegotiate" ) );
return( 0 );
}
/*
* Renegotiate current connection on client,
* or request renegotiation on server
*/
int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
#if defined(MBEDTLS_SSL_SRV_C)
/* On server, just send the request */
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
{
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->renego_status = MBEDTLS_SSL_RENEGOTIATION_PENDING;
/* Did we already try/start sending HelloRequest? */
if( ssl->out_left != 0 )
return( mbedtls_ssl_flush_output( ssl ) );
return( ssl_write_hello_request( ssl ) );
}
#endif /* MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_SSL_CLI_C)
/*
* On client, either start the renegotiation process or,
* if already in progress, continue the handshake
*/
if( ssl->renego_status != MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
{
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( ( ret = ssl_start_renegotiation( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_start_renegotiation", ret );
return( ret );
}
}
else
{
if( ( ret = mbedtls_ssl_handshake( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_handshake", ret );
return( ret );
}
}
#endif /* MBEDTLS_SSL_CLI_C */
return( ret );
}
/*
* Check record counters and renegotiate if they're above the limit.
*/
static int ssl_check_ctr_renegotiate( mbedtls_ssl_context *ssl )
{
size_t ep_len = ssl_ep_len( ssl );
int in_ctr_cmp;
int out_ctr_cmp;
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER ||
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING ||
ssl->conf->disable_renegotiation == MBEDTLS_SSL_RENEGOTIATION_DISABLED )
{
return( 0 );
}
in_ctr_cmp = memcmp( ssl->in_ctr + ep_len,
ssl->conf->renego_period + ep_len, 8 - ep_len );
out_ctr_cmp = memcmp( ssl->cur_out_ctr + ep_len,
ssl->conf->renego_period + ep_len, 8 - ep_len );
if( in_ctr_cmp <= 0 && out_ctr_cmp <= 0 )
{
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "record counter limit reached: renegotiate" ) );
return( mbedtls_ssl_renegotiate( ssl ) );
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/*
* Receive application data decrypted from the SSL layer
*/
int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t n;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> read" ) );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
return( ret );
if( ssl->handshake != NULL &&
ssl->handshake->retransmit_state == MBEDTLS_SSL_RETRANS_SENDING )
{
if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
return( ret );
}
}
#endif
/*
* Check if renegotiation is necessary and/or handshake is
* in process. If yes, perform/continue, and fall through
* if an unexpected packet is received while the client
* is waiting for the ServerHello.
*
* (There is no equivalent to the last condition on
* the server-side as it is not treated as within
* a handshake while waiting for the ClientHello
* after a renegotiation request.)
*/
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ret = ssl_check_ctr_renegotiate( ssl );
if( ret != MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO &&
ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_check_ctr_renegotiate", ret );
return( ret );
}
#endif
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
ret = mbedtls_ssl_handshake( ssl );
if( ret != MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO &&
ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_handshake", ret );
return( ret );
}
}
/* Loop as long as no application data record is available */
while( ssl->in_offt == NULL )
{
/* Start timer if not already running */
if( ssl->f_get_timer != NULL &&
ssl->f_get_timer( ssl->p_timer ) == -1 )
{
ssl_set_timer( ssl, ssl->conf->read_timeout );
}
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 )
{
if( ret == MBEDTLS_ERR_SSL_CONN_EOF )
return( 0 );
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msglen == 0 &&
ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA )
{
/*
* OpenSSL sends empty messages to randomize the IV
*/
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 )
{
if( ret == MBEDTLS_ERR_SSL_CONN_EOF )
return( 0 );
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
}
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "received handshake message" ) );
/*
* - For client-side, expect SERVER_HELLO_REQUEST.
* - For server-side, expect CLIENT_HELLO.
* - Fail (TLS) or silently drop record (DTLS) in other cases.
*/
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT &&
( ssl->in_msg[0] != MBEDTLS_SSL_HS_HELLO_REQUEST ||
ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "handshake received (not HelloRequest)" ) );
/* With DTLS, drop the packet (probably from last handshake) */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
continue;
}
#endif
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
#endif /* MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->in_msg[0] != MBEDTLS_SSL_HS_CLIENT_HELLO )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "handshake received (not ClientHello)" ) );
/* With DTLS, drop the packet (probably from last handshake) */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
continue;
}
#endif
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
#endif /* MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_SSL_RENEGOTIATION)
/* Determine whether renegotiation attempt should be accepted */
if( ! ( ssl->conf->disable_renegotiation == MBEDTLS_SSL_RENEGOTIATION_DISABLED ||
( ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
ssl->conf->allow_legacy_renegotiation ==
MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION ) ) )
{
/*
* Accept renegotiation request
*/
/* DTLS clients need to know renego is server-initiated */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
{
ssl->renego_status = MBEDTLS_SSL_RENEGOTIATION_PENDING;
}
#endif
ret = ssl_start_renegotiation( ssl );
if( ret != MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO &&
ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_start_renegotiation", ret );
return( ret );
}
}
else
#endif /* MBEDTLS_SSL_RENEGOTIATION */
{
/*
* Refuse renegotiation
*/
MBEDTLS_SSL_DEBUG_MSG( 3, ( "refusing renegotiation, sending alert" ) );
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
/* SSLv3 does not have a "no_renegotiation" warning, so
we send a fatal alert and abort the connection. */
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 )
{
if( ( ret = mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_WARNING,
MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION ) ) != 0 )
{
return( ret );
}
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 ||
MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
/* At this point, we don't know whether the renegotiation has been
* completed or not. The cases to consider are the following:
* 1) The renegotiation is complete. In this case, no new record
* has been read yet.
* 2) The renegotiation is incomplete because the client received
* an application data record while awaiting the ServerHello.
* 3) The renegotiation is incomplete because the client received
* a non-handshake, non-application data message while awaiting
* the ServerHello.
* In each of these case, looping will be the proper action:
* - For 1), the next iteration will read a new record and check
* if it's application data.
* - For 2), the loop condition isn't satisfied as application data
* is present, hence continue is the same as break
* - For 3), the loop condition is satisfied and read_record
* will re-deliver the message that was held back by the client
* when expecting the ServerHello.
*/
continue;
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING )
{
if( ssl->conf->renego_max_records >= 0 )
{
if( ++ssl->renego_records_seen > ssl->conf->renego_max_records )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "renegotiation requested, "
"but not honored by client" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
}
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/* Fatal and closure alerts handled by mbedtls_ssl_read_record() */
if( ssl->in_msgtype == MBEDTLS_SSL_MSG_ALERT )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "ignoring non-fatal non-closure alert" ) );
return( MBEDTLS_ERR_SSL_WANT_READ );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_APPLICATION_DATA )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad application data message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
ssl->in_offt = ssl->in_msg;
/* We're going to return something now, cancel timer,
* except if handshake (renegotiation) is in progress */
if( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER )
ssl_set_timer( ssl, 0 );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/* If we requested renego but received AppData, resend HelloRequest.
* Do it now, after setting in_offt, to avoid taking this branch
* again if ssl_write_hello_request() returns WANT_WRITE */
#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING )
{
if( ( ret = ssl_resend_hello_request( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_resend_hello_request", ret );
return( ret );
}
}
#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_RENEGOTIATION */
#endif /* MBEDTLS_SSL_PROTO_DTLS */
}
n = ( len < ssl->in_msglen )
? len : ssl->in_msglen;
memcpy( buf, ssl->in_offt, n );
ssl->in_msglen -= n;
if( ssl->in_msglen == 0 )
{
/* all bytes consumed */
ssl->in_offt = NULL;
ssl->keep_current_message = 0;
}
else
{
/* more data available */
ssl->in_offt += n;
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= read" ) );
return( (int) n );
}
/*
* Send application data to be encrypted by the SSL layer, taking care of max
* fragment length and buffer size.
*
* According to RFC 5246 Section 6.2.1:
*
* Zero-length fragments of Application data MAY be sent as they are
* potentially useful as a traffic analysis countermeasure.
*
* Therefore, it is possible that the input message length is 0 and the
* corresponding return code is 0 on success.
*/
static int ssl_write_real( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
int ret = mbedtls_ssl_get_max_out_record_payload( ssl );
const size_t max_len = (size_t) ret;
if( ret < 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_get_max_out_record_payload", ret );
return( ret );
}
if( len > max_len )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "fragment larger than the (negotiated) "
"maximum fragment length: %d > %d",
len, max_len ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
else
#endif
len = max_len;
}
if( ssl->out_left != 0 )
{
/*
* The user has previously tried to send the data and
* MBEDTLS_ERR_SSL_WANT_WRITE or the message was only partially
* written. In this case, we expect the high-level write function
* (e.g. mbedtls_ssl_write()) to be called with the same parameters
*/
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flush_output", ret );
return( ret );
}
}
else
{
/*
* The user is trying to send a message the first time, so we need to
* copy the data into the internal buffers and setup the data structure
* to keep track of partial writes
*/
ssl->out_msglen = len;
ssl->out_msgtype = MBEDTLS_SSL_MSG_APPLICATION_DATA;
memcpy( ssl->out_msg, buf, len );
if( ( ret = mbedtls_ssl_write_record( ssl, SSL_FORCE_FLUSH ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
}
return( (int) len );
}
/*
* Write application data, doing 1/n-1 splitting if necessary.
*
* With non-blocking I/O, ssl_write_real() may return WANT_WRITE,
* then the caller will call us again with the same arguments, so
* remember whether we already did the split or not.
*/
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
static int ssl_write_split( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ssl->conf->cbc_record_splitting ==
MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED ||
len <= 1 ||
ssl->minor_ver > MBEDTLS_SSL_MINOR_VERSION_1 ||
mbedtls_cipher_get_cipher_mode( &ssl->transform_out->cipher_ctx_enc )
!= MBEDTLS_MODE_CBC )
{
return( ssl_write_real( ssl, buf, len ) );
}
if( ssl->split_done == 0 )
{
if( ( ret = ssl_write_real( ssl, buf, 1 ) ) <= 0 )
return( ret );
ssl->split_done = 1;
}
if( ( ret = ssl_write_real( ssl, buf + 1, len - 1 ) ) <= 0 )
return( ret );
ssl->split_done = 0;
return( ret + 1 );
}
#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
/*
* Write application data (public-facing wrapper)
*/
int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write" ) );
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ( ret = ssl_check_ctr_renegotiate( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_check_ctr_renegotiate", ret );
return( ret );
}
#endif
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
if( ( ret = mbedtls_ssl_handshake( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_handshake", ret );
return( ret );
}
}
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
ret = ssl_write_split( ssl, buf, len );
#else
ret = ssl_write_real( ssl, buf, len );
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write" ) );
return( ret );
}
/*
* Notify the peer that the connection is being closed
*/
int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if( ssl == NULL || ssl->conf == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write close notify" ) );
if( ssl->out_left != 0 )
return( mbedtls_ssl_flush_output( ssl ) );
if( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER )
{
if( ( ret = mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_WARNING,
MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_send_alert_message", ret );
return( ret );
}
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write close notify" ) );
return( 0 );
}
void mbedtls_ssl_transform_free( mbedtls_ssl_transform *transform )
{
if( transform == NULL )
return;
#if defined(MBEDTLS_ZLIB_SUPPORT)
deflateEnd( &transform->ctx_deflate );
inflateEnd( &transform->ctx_inflate );
#endif
mbedtls_cipher_free( &transform->cipher_ctx_enc );
mbedtls_cipher_free( &transform->cipher_ctx_dec );
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
mbedtls_md_free( &transform->md_ctx_enc );
mbedtls_md_free( &transform->md_ctx_dec );
#endif
mbedtls_platform_zeroize( transform, sizeof( mbedtls_ssl_transform ) );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
static void ssl_key_cert_free( mbedtls_ssl_key_cert *key_cert )
{
mbedtls_ssl_key_cert *cur = key_cert, *next;
while( cur != NULL )
{
next = cur->next;
mbedtls_free( cur );
cur = next;
}
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static void ssl_buffering_free( mbedtls_ssl_context *ssl )
{
unsigned offset;
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
if( hs == NULL )
return;
ssl_free_buffered_record( ssl );
for( offset = 0; offset < MBEDTLS_SSL_MAX_BUFFERED_HS; offset++ )
ssl_buffering_free_slot( ssl, offset );
}
static void ssl_buffering_free_slot( mbedtls_ssl_context *ssl,
uint8_t slot )
{
mbedtls_ssl_handshake_params * const hs = ssl->handshake;
mbedtls_ssl_hs_buffer * const hs_buf = &hs->buffering.hs[slot];
if( slot >= MBEDTLS_SSL_MAX_BUFFERED_HS )
return;
if( hs_buf->is_valid == 1 )
{
hs->buffering.total_bytes_buffered -= hs_buf->data_len;
mbedtls_platform_zeroize( hs_buf->data, hs_buf->data_len );
mbedtls_free( hs_buf->data );
memset( hs_buf, 0, sizeof( mbedtls_ssl_hs_buffer ) );
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
void mbedtls_ssl_handshake_free( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_handshake_params *handshake = ssl->handshake;
if( handshake == NULL )
return;
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
if( ssl->conf->f_async_cancel != NULL && handshake->async_in_progress != 0 )
{
ssl->conf->f_async_cancel( ssl );
handshake->async_in_progress = 0;
}
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
mbedtls_md5_free( &handshake->fin_md5 );
mbedtls_sha1_free( &handshake->fin_sha1 );
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_SHA256_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_abort( &handshake->fin_sha256_psa );
#else
mbedtls_sha256_free( &handshake->fin_sha256 );
#endif
#endif
#if defined(MBEDTLS_SHA512_C)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_hash_abort( &handshake->fin_sha384_psa );
#else
mbedtls_sha512_free( &handshake->fin_sha512 );
#endif
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_DHM_C)
mbedtls_dhm_free( &handshake->dhm_ctx );
#endif
#if defined(MBEDTLS_ECDH_C)
mbedtls_ecdh_free( &handshake->ecdh_ctx );
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
mbedtls_ecjpake_free( &handshake->ecjpake_ctx );
#if defined(MBEDTLS_SSL_CLI_C)
mbedtls_free( handshake->ecjpake_cache );
handshake->ecjpake_cache = NULL;
handshake->ecjpake_cache_len = 0;
#endif
#endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
/* explicit void pointer cast for buggy MS compiler */
mbedtls_free( (void *) handshake->curves );
#endif
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( handshake->psk != NULL )
{
mbedtls_platform_zeroize( handshake->psk, handshake->psk_len );
mbedtls_free( handshake->psk );
}
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C) && \
defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
/*
* Free only the linked list wrapper, not the keys themselves
* since the belong to the SNI callback
*/
if( handshake->sni_key_cert != NULL )
{
mbedtls_ssl_key_cert *cur = handshake->sni_key_cert, *next;
while( cur != NULL )
{
next = cur->next;
mbedtls_free( cur );
cur = next;
}
}
#endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
mbedtls_x509_crt_restart_free( &handshake->ecrs_ctx );
if( handshake->ecrs_peer_cert != NULL )
{
mbedtls_x509_crt_free( handshake->ecrs_peer_cert );
mbedtls_free( handshake->ecrs_peer_cert );
}
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C) && \
!defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
mbedtls_pk_free( &handshake->peer_pubkey );
#endif /* MBEDTLS_X509_CRT_PARSE_C && !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
mbedtls_free( handshake->verify_cookie );
ssl_flight_free( handshake->flight );
ssl_buffering_free( ssl );
#endif
#if defined(MBEDTLS_ECDH_C) && \
defined(MBEDTLS_USE_PSA_CRYPTO)
psa_destroy_key( handshake->ecdh_psa_privkey );
#endif /* MBEDTLS_ECDH_C && MBEDTLS_USE_PSA_CRYPTO */
mbedtls_platform_zeroize( handshake,
sizeof( mbedtls_ssl_handshake_params ) );
}
void mbedtls_ssl_session_free( mbedtls_ssl_session *session )
{
if( session == NULL )
return;
#if defined(MBEDTLS_X509_CRT_PARSE_C)
ssl_clear_peer_cert( session );
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
mbedtls_free( session->ticket );
#endif
mbedtls_platform_zeroize( session, sizeof( mbedtls_ssl_session ) );
}
#if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_CONNECTION_ID 1u
#else
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_CONNECTION_ID 0u
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_BADMAC_LIMIT 1u
#else
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_BADMAC_LIMIT 0u
#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_ANTI_REPLAY 1u
#else
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_ANTI_REPLAY 0u
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
#if defined(MBEDTLS_SSL_ALPN)
#define SSL_SERIALIZED_CONTEXT_CONFIG_ALPN 1u
#else
#define SSL_SERIALIZED_CONTEXT_CONFIG_ALPN 0u
#endif /* MBEDTLS_SSL_ALPN */
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_CONNECTION_ID_BIT 0
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_BADMAC_LIMIT_BIT 1
#define SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_ANTI_REPLAY_BIT 2
#define SSL_SERIALIZED_CONTEXT_CONFIG_ALPN_BIT 3
#define SSL_SERIALIZED_CONTEXT_CONFIG_BITFLAG \
( (uint32_t) ( \
( SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_CONNECTION_ID << SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_CONNECTION_ID_BIT ) | \
( SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_BADMAC_LIMIT << SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_BADMAC_LIMIT_BIT ) | \
( SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_ANTI_REPLAY << SSL_SERIALIZED_CONTEXT_CONFIG_DTLS_ANTI_REPLAY_BIT ) | \
( SSL_SERIALIZED_CONTEXT_CONFIG_ALPN << SSL_SERIALIZED_CONTEXT_CONFIG_ALPN_BIT ) | \
0u ) )
static unsigned char ssl_serialized_context_header[] = {
MBEDTLS_VERSION_MAJOR,
MBEDTLS_VERSION_MINOR,
MBEDTLS_VERSION_PATCH,
( SSL_SERIALIZED_SESSION_CONFIG_BITFLAG >> 8 ) & 0xFF,
( SSL_SERIALIZED_SESSION_CONFIG_BITFLAG >> 0 ) & 0xFF,
( SSL_SERIALIZED_CONTEXT_CONFIG_BITFLAG >> 16 ) & 0xFF,
( SSL_SERIALIZED_CONTEXT_CONFIG_BITFLAG >> 8 ) & 0xFF,
( SSL_SERIALIZED_CONTEXT_CONFIG_BITFLAG >> 0 ) & 0xFF,
};
/*
* Serialize a full SSL context
*
* The format of the serialized data is:
* (in the presentation language of TLS, RFC 8446 section 3)
*
* // header
* opaque mbedtls_version[3]; // major, minor, patch
* opaque context_format[5]; // version-specific field determining
* // the format of the remaining
* // serialized data.
* Note: When updating the format, remember to keep these
* version+format bytes. (We may make their size part of the API.)
*
* // session sub-structure
* opaque session<1..2^32-1>; // see mbedtls_ssl_session_save()
* // transform sub-structure
* uint8 random[64]; // ServerHello.random+ClientHello.random
* uint8 in_cid<0..2^8-1> // Connection ID: expected incoming value
* uint8 out_cid<0..2^8-1> // Connection ID: outgoing value to use
* // fields from ssl_context
* uint32 badmac_seen; // DTLS: number of records with failing MAC
* uint64 in_window_top; // DTLS: last validated record seq_num
* uint64 in_window; // DTLS: bitmask for replay protection
* uint8 disable_datagram_packing; // DTLS: only one record per datagram
* uint64 cur_out_ctr; // Record layer: outgoing sequence number
* uint16 mtu; // DTLS: path mtu (max outgoing fragment size)
* uint8 alpn_chosen<0..2^8-1> // ALPN: negotiated application protocol
*
* Note that many fields of the ssl_context or sub-structures are not
* serialized, as they fall in one of the following categories:
*
* 1. forced value (eg in_left must be 0)
* 2. pointer to dynamically-allocated memory (eg session, transform)
* 3. value can be re-derived from other data (eg session keys from MS)
* 4. value was temporary (eg content of input buffer)
* 5. value will be provided by the user again (eg I/O callbacks and context)
*/
int mbedtls_ssl_context_save( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t buf_len,
size_t *olen )
{
unsigned char *p = buf;
size_t used = 0;
size_t session_len;
int ret = 0;
/*
* Enforce usage restrictions, see "return BAD_INPUT_DATA" in
* this function's documentation.
*
* These are due to assumptions/limitations in the implementation. Some of
* them are likely to stay (no handshake in progress) some might go away
* (only DTLS) but are currently used to simplify the implementation.
*/
/* The initial handshake must be over */
if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Initial handshake isn't over" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
if( ssl->handshake != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Handshake isn't completed" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Double-check that sub-structures are indeed ready */
if( ssl->transform == NULL || ssl->session == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Serialised structures aren't ready" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* There must be no pending incoming or outgoing data */
if( mbedtls_ssl_check_pending( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "There is pending incoming data" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
if( ssl->out_left != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "There is pending outgoing data" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Protocol must be DLTS, not TLS */
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Only DTLS is supported" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Version must be 1.2 */
if( ssl->major_ver != MBEDTLS_SSL_MAJOR_VERSION_3 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Only version 1.2 supported" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Only version 1.2 supported" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* We must be using an AEAD ciphersuite */
if( mbedtls_ssl_transform_uses_aead( ssl->transform ) != 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Only AEAD ciphersuites supported" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/* Renegotiation must not be enabled */
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->conf->disable_renegotiation != MBEDTLS_SSL_RENEGOTIATION_DISABLED )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Renegotiation must not be enabled" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
#endif
/*
* Version and format identifier
*/
used += sizeof( ssl_serialized_context_header );
if( used <= buf_len )
{
memcpy( p, ssl_serialized_context_header,
sizeof( ssl_serialized_context_header ) );
p += sizeof( ssl_serialized_context_header );
}
/*
* Session (length + data)
*/
ret = ssl_session_save( ssl->session, 1, NULL, 0, &session_len );
if( ret != MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL )
return( ret );
used += 4 + session_len;
if( used <= buf_len )
{
*p++ = (unsigned char)( ( session_len >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( session_len >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( session_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( session_len ) & 0xFF );
ret = ssl_session_save( ssl->session, 1,
p, session_len, &session_len );
if( ret != 0 )
return( ret );
p += session_len;
}
/*
* Transform
*/
used += sizeof( ssl->transform->randbytes );
if( used <= buf_len )
{
memcpy( p, ssl->transform->randbytes,
sizeof( ssl->transform->randbytes ) );
p += sizeof( ssl->transform->randbytes );
}
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
used += 2 + ssl->transform->in_cid_len + ssl->transform->out_cid_len;
if( used <= buf_len )
{
*p++ = ssl->transform->in_cid_len;
memcpy( p, ssl->transform->in_cid, ssl->transform->in_cid_len );
p += ssl->transform->in_cid_len;
*p++ = ssl->transform->out_cid_len;
memcpy( p, ssl->transform->out_cid, ssl->transform->out_cid_len );
p += ssl->transform->out_cid_len;
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
/*
* Saved fields from top-level ssl_context structure
*/
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
used += 4;
if( used <= buf_len )
{
*p++ = (unsigned char)( ( ssl->badmac_seen >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->badmac_seen >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->badmac_seen >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->badmac_seen ) & 0xFF );
}
#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
used += 16;
if( used <= buf_len )
{
*p++ = (unsigned char)( ( ssl->in_window_top >> 56 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 48 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 40 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 32 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window_top ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 56 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 48 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 40 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 32 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 24 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 16 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->in_window ) & 0xFF );
}
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
used += 1;
if( used <= buf_len )
{
*p++ = ssl->disable_datagram_packing;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
used += 8;
if( used <= buf_len )
{
memcpy( p, ssl->cur_out_ctr, 8 );
p += 8;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
used += 2;
if( used <= buf_len )
{
*p++ = (unsigned char)( ( ssl->mtu >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ssl->mtu ) & 0xFF );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_SSL_ALPN)
{
const uint8_t alpn_len = ssl->alpn_chosen
? (uint8_t) strlen( ssl->alpn_chosen )
: 0;
used += 1 + alpn_len;
if( used <= buf_len )
{
*p++ = alpn_len;
if( ssl->alpn_chosen != NULL )
{
memcpy( p, ssl->alpn_chosen, alpn_len );
p += alpn_len;
}
}
}
#endif /* MBEDTLS_SSL_ALPN */
/*
* Done
*/
*olen = used;
if( used > buf_len )
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
MBEDTLS_SSL_DEBUG_BUF( 4, "saved context", buf, used );
return( ssl_session_reset_int( ssl, 0 ) );
}
/*
* Helper to get TLS 1.2 PRF from ciphersuite
* (Duplicates bits of logic from ssl_set_handshake_prfs().)
*/
typedef int (*tls_prf_fn)( const unsigned char *secret, size_t slen,
const char *label,
const unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen );
static tls_prf_fn ssl_tls12prf_from_cs( int ciphersuite_id )
{
#if defined(MBEDTLS_SHA512_C)
const mbedtls_ssl_ciphersuite_t * const ciphersuite_info =
mbedtls_ssl_ciphersuite_from_id( ciphersuite_id );
if( ciphersuite_info->mac == MBEDTLS_MD_SHA384 )
return( tls_prf_sha384 );
#else
(void) ciphersuite_id;
#endif
return( tls_prf_sha256 );
}
/*
* Deserialize context, see mbedtls_ssl_context_save() for format.
*
* This internal version is wrapped by a public function that cleans up in
* case of error.
*/
static int ssl_context_load( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
const unsigned char *p = buf;
const unsigned char * const end = buf + len;
size_t session_len;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
/*
* The context should have been freshly setup or reset.
* Give the user an error in case of obvious misuse.
* (Checking session is useful because it won't be NULL if we're
* renegotiating, or if the user mistakenly loaded a session first.)
*/
if( ssl->state != MBEDTLS_SSL_HELLO_REQUEST ||
ssl->session != NULL )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/*
* We can't check that the config matches the initial one, but we can at
* least check it matches the requirements for serializing.
*/
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ||
ssl->conf->max_major_ver < MBEDTLS_SSL_MAJOR_VERSION_3 ||
ssl->conf->min_major_ver > MBEDTLS_SSL_MAJOR_VERSION_3 ||
ssl->conf->max_minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 ||
ssl->conf->min_minor_ver > MBEDTLS_SSL_MINOR_VERSION_3 ||
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->conf->disable_renegotiation != MBEDTLS_SSL_RENEGOTIATION_DISABLED ||
#endif
0 )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "context to load", buf, len );
/*
* Check version identifier
*/
if( (size_t)( end - p ) < sizeof( ssl_serialized_context_header ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( memcmp( p, ssl_serialized_context_header,
sizeof( ssl_serialized_context_header ) ) != 0 )
{
return( MBEDTLS_ERR_SSL_VERSION_MISMATCH );
}
p += sizeof( ssl_serialized_context_header );
/*
* Session
*/
if( (size_t)( end - p ) < 4 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
session_len = ( (size_t) p[0] << 24 ) |
( (size_t) p[1] << 16 ) |
( (size_t) p[2] << 8 ) |
( (size_t) p[3] );
p += 4;
/* This has been allocated by ssl_handshake_init(), called by
* by either ssl_session_reset_int() or mbedtls_ssl_setup(). */
ssl->session = ssl->session_negotiate;
ssl->session_in = ssl->session;
ssl->session_out = ssl->session;
ssl->session_negotiate = NULL;
if( (size_t)( end - p ) < session_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ret = ssl_session_load( ssl->session, 1, p, session_len );
if( ret != 0 )
{
mbedtls_ssl_session_free( ssl->session );
return( ret );
}
p += session_len;
/*
* Transform
*/
/* This has been allocated by ssl_handshake_init(), called by
* by either ssl_session_reset_int() or mbedtls_ssl_setup(). */
ssl->transform = ssl->transform_negotiate;
ssl->transform_in = ssl->transform;
ssl->transform_out = ssl->transform;
ssl->transform_negotiate = NULL;
/* Read random bytes and populate structure */
if( (size_t)( end - p ) < sizeof( ssl->transform->randbytes ) )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ret = ssl_populate_transform( ssl->transform,
ssl->session->ciphersuite,
ssl->session->master,
#if defined(MBEDTLS_SSL_SOME_MODES_USE_MAC)
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
ssl->session->encrypt_then_mac,
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
ssl->session->trunc_hmac,
#endif
#endif /* MBEDTLS_SSL_SOME_MODES_USE_MAC */
#if defined(MBEDTLS_ZLIB_SUPPORT)
ssl->session->compression,
#endif
ssl_tls12prf_from_cs( ssl->session->ciphersuite ),
p, /* currently pointing to randbytes */
MBEDTLS_SSL_MINOR_VERSION_3, /* (D)TLS 1.2 is forced */
ssl->conf->endpoint,
ssl );
if( ret != 0 )
return( ret );
p += sizeof( ssl->transform->randbytes );
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
/* Read connection IDs and store them */
if( (size_t)( end - p ) < 1 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->transform->in_cid_len = *p++;
if( (size_t)( end - p ) < ssl->transform->in_cid_len + 1u )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( ssl->transform->in_cid, p, ssl->transform->in_cid_len );
p += ssl->transform->in_cid_len;
ssl->transform->out_cid_len = *p++;
if( (size_t)( end - p ) < ssl->transform->out_cid_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( ssl->transform->out_cid, p, ssl->transform->out_cid_len );
p += ssl->transform->out_cid_len;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
/*
* Saved fields from top-level ssl_context structure
*/
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
if( (size_t)( end - p ) < 4 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->badmac_seen = ( (uint32_t) p[0] << 24 ) |
( (uint32_t) p[1] << 16 ) |
( (uint32_t) p[2] << 8 ) |
( (uint32_t) p[3] );
p += 4;
#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
if( (size_t)( end - p ) < 16 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->in_window_top = ( (uint64_t) p[0] << 56 ) |
( (uint64_t) p[1] << 48 ) |
( (uint64_t) p[2] << 40 ) |
( (uint64_t) p[3] << 32 ) |
( (uint64_t) p[4] << 24 ) |
( (uint64_t) p[5] << 16 ) |
( (uint64_t) p[6] << 8 ) |
( (uint64_t) p[7] );
p += 8;
ssl->in_window = ( (uint64_t) p[0] << 56 ) |
( (uint64_t) p[1] << 48 ) |
( (uint64_t) p[2] << 40 ) |
( (uint64_t) p[3] << 32 ) |
( (uint64_t) p[4] << 24 ) |
( (uint64_t) p[5] << 16 ) |
( (uint64_t) p[6] << 8 ) |
( (uint64_t) p[7] );
p += 8;
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( (size_t)( end - p ) < 1 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->disable_datagram_packing = *p++;
#endif /* MBEDTLS_SSL_PROTO_DTLS */
if( (size_t)( end - p ) < 8 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( ssl->cur_out_ctr, p, 8 );
p += 8;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( (size_t)( end - p ) < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
ssl->mtu = ( p[0] << 8 ) | p[1];
p += 2;
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_SSL_ALPN)
{
uint8_t alpn_len;
const char **cur;
if( (size_t)( end - p ) < 1 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
alpn_len = *p++;
if( alpn_len != 0 && ssl->conf->alpn_list != NULL )
{
/* alpn_chosen should point to an item in the configured list */
for( cur = ssl->conf->alpn_list; *cur != NULL; cur++ )
{
if( strlen( *cur ) == alpn_len &&
memcmp( p, cur, alpn_len ) == 0 )
{
ssl->alpn_chosen = *cur;
break;
}
}
}
/* can only happen on conf mismatch */
if( alpn_len != 0 && ssl->alpn_chosen == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
p += alpn_len;
}
#endif /* MBEDTLS_SSL_ALPN */
/*
* Forced fields from top-level ssl_context structure
*
* Most of them already set to the correct value by mbedtls_ssl_init() and
* mbedtls_ssl_reset(), so we only need to set the remaining ones.
*/
ssl->state = MBEDTLS_SSL_HANDSHAKE_OVER;
ssl->major_ver = MBEDTLS_SSL_MAJOR_VERSION_3;
ssl->minor_ver = MBEDTLS_SSL_MINOR_VERSION_3;
/* Adjust pointers for header fields of outgoing records to
* the given transform, accounting for explicit IV and CID. */
ssl_update_out_pointers( ssl, ssl->transform );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
ssl->in_epoch = 1;
#endif
/* mbedtls_ssl_reset() leaves the handshake sub-structure allocated,
* which we don't want - otherwise we'd end up freeing the wrong transform
* by calling ssl_handshake_wrapup_free_hs_transform() inappropriately. */
if( ssl->handshake != NULL )
{
mbedtls_ssl_handshake_free( ssl );
mbedtls_free( ssl->handshake );
ssl->handshake = NULL;
}
/*
* Done - should have consumed entire buffer
*/
if( p != end )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
return( 0 );
}
/*
* Deserialize context: public wrapper for error cleaning
*/
int mbedtls_ssl_context_load( mbedtls_ssl_context *context,
const unsigned char *buf,
size_t len )
{
int ret = ssl_context_load( context, buf, len );
if( ret != 0 )
mbedtls_ssl_free( context );
return( ret );
}
#endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
/*
* Free an SSL context
*/
void mbedtls_ssl_free( mbedtls_ssl_context *ssl )
{
if( ssl == NULL )
return;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> free" ) );
if( ssl->out_buf != NULL )
{
mbedtls_platform_zeroize( ssl->out_buf, MBEDTLS_SSL_OUT_BUFFER_LEN );
mbedtls_free( ssl->out_buf );
}
if( ssl->in_buf != NULL )
{
mbedtls_platform_zeroize( ssl->in_buf, MBEDTLS_SSL_IN_BUFFER_LEN );
mbedtls_free( ssl->in_buf );
}
#if defined(MBEDTLS_ZLIB_SUPPORT)
if( ssl->compress_buf != NULL )
{
mbedtls_platform_zeroize( ssl->compress_buf, MBEDTLS_SSL_COMPRESS_BUFFER_LEN );
mbedtls_free( ssl->compress_buf );
}
#endif
if( ssl->transform )
{
mbedtls_ssl_transform_free( ssl->transform );
mbedtls_free( ssl->transform );
}
if( ssl->handshake )
{
mbedtls_ssl_handshake_free( ssl );
mbedtls_ssl_transform_free( ssl->transform_negotiate );
mbedtls_ssl_session_free( ssl->session_negotiate );
mbedtls_free( ssl->handshake );
mbedtls_free( ssl->transform_negotiate );
mbedtls_free( ssl->session_negotiate );
}
if( ssl->session )
{
mbedtls_ssl_session_free( ssl->session );
mbedtls_free( ssl->session );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
if( ssl->hostname != NULL )
{
mbedtls_platform_zeroize( ssl->hostname, strlen( ssl->hostname ) );
mbedtls_free( ssl->hostname );
}
#endif
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_finish != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_finish()" ) );
mbedtls_ssl_hw_record_finish( ssl );
}
#endif
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
mbedtls_free( ssl->cli_id );
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= free" ) );
/* Actually clear after last debug message */
mbedtls_platform_zeroize( ssl, sizeof( mbedtls_ssl_context ) );
}
/*
* Initialze mbedtls_ssl_config
*/
void mbedtls_ssl_config_init( mbedtls_ssl_config *conf )
{
memset( conf, 0, sizeof( mbedtls_ssl_config ) );
}
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
static int ssl_preset_default_hashes[] = {
#if defined(MBEDTLS_SHA512_C)
MBEDTLS_MD_SHA512,
MBEDTLS_MD_SHA384,
#endif
#if defined(MBEDTLS_SHA256_C)
MBEDTLS_MD_SHA256,
MBEDTLS_MD_SHA224,
#endif
#if defined(MBEDTLS_SHA1_C) && defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
MBEDTLS_MD_SHA1,
#endif
MBEDTLS_MD_NONE
};
#endif
static int ssl_preset_suiteb_ciphersuites[] = {
MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
0
};
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
static int ssl_preset_suiteb_hashes[] = {
MBEDTLS_MD_SHA256,
MBEDTLS_MD_SHA384,
MBEDTLS_MD_NONE
};
#endif
#if defined(MBEDTLS_ECP_C)
static mbedtls_ecp_group_id ssl_preset_suiteb_curves[] = {
#if defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
MBEDTLS_ECP_DP_SECP256R1,
#endif
#if defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
MBEDTLS_ECP_DP_SECP384R1,
#endif
MBEDTLS_ECP_DP_NONE
};
#endif
/*
* Load default in mbedtls_ssl_config
*/
int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf,
int endpoint, int transport, int preset )
{
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
#endif
/* Use the functions here so that they are covered in tests,
* but otherwise access member directly for efficiency */
mbedtls_ssl_conf_endpoint( conf, endpoint );
mbedtls_ssl_conf_transport( conf, transport );
/*
* Things that are common to all presets
*/
#if defined(MBEDTLS_SSL_CLI_C)
if( endpoint == MBEDTLS_SSL_IS_CLIENT )
{
conf->authmode = MBEDTLS_SSL_VERIFY_REQUIRED;
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
conf->session_tickets = MBEDTLS_SSL_SESSION_TICKETS_ENABLED;
#endif
}
#endif
#if defined(MBEDTLS_ARC4_C)
conf->arc4_disabled = MBEDTLS_SSL_ARC4_DISABLED;
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
conf->encrypt_then_mac = MBEDTLS_SSL_ETM_ENABLED;
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
conf->extended_ms = MBEDTLS_SSL_EXTENDED_MS_ENABLED;
#endif
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
conf->cbc_record_splitting = MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED;
#endif
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
conf->f_cookie_write = ssl_cookie_write_dummy;
conf->f_cookie_check = ssl_cookie_check_dummy;
#endif
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
conf->anti_replay = MBEDTLS_SSL_ANTI_REPLAY_ENABLED;
#endif
#if defined(MBEDTLS_SSL_SRV_C)
conf->cert_req_ca_list = MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED;
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
conf->hs_timeout_min = MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN;
conf->hs_timeout_max = MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX;
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
conf->renego_max_records = MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT;
memset( conf->renego_period, 0x00, 2 );
memset( conf->renego_period + 2, 0xFF, 6 );
#endif
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
if( endpoint == MBEDTLS_SSL_IS_SERVER )
{
const unsigned char dhm_p[] =
MBEDTLS_DHM_RFC3526_MODP_2048_P_BIN;
const unsigned char dhm_g[] =
MBEDTLS_DHM_RFC3526_MODP_2048_G_BIN;
if ( ( ret = mbedtls_ssl_conf_dh_param_bin( conf,
dhm_p, sizeof( dhm_p ),
dhm_g, sizeof( dhm_g ) ) ) != 0 )
{
return( ret );
}
}
#endif
/*
* Preset-specific defaults
*/
switch( preset )
{
/*
* NSA Suite B
*/
case MBEDTLS_SSL_PRESET_SUITEB:
conf->min_major_ver = MBEDTLS_SSL_MAJOR_VERSION_3;
conf->min_minor_ver = MBEDTLS_SSL_MINOR_VERSION_3; /* TLS 1.2 */
conf->max_major_ver = MBEDTLS_SSL_MAX_MAJOR_VERSION;
conf->max_minor_ver = MBEDTLS_SSL_MAX_MINOR_VERSION;
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_0] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_1] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_2] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_3] =
ssl_preset_suiteb_ciphersuites;
#if defined(MBEDTLS_X509_CRT_PARSE_C)
conf->cert_profile = &mbedtls_x509_crt_profile_suiteb;
#endif
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
conf->sig_hashes = ssl_preset_suiteb_hashes;
#endif
#if defined(MBEDTLS_ECP_C)
conf->curve_list = ssl_preset_suiteb_curves;
#endif
break;
/*
* Default
*/
default:
conf->min_major_ver = ( MBEDTLS_SSL_MIN_MAJOR_VERSION >
MBEDTLS_SSL_MIN_VALID_MAJOR_VERSION ) ?
MBEDTLS_SSL_MIN_MAJOR_VERSION :
MBEDTLS_SSL_MIN_VALID_MAJOR_VERSION;
conf->min_minor_ver = ( MBEDTLS_SSL_MIN_MINOR_VERSION >
MBEDTLS_SSL_MIN_VALID_MINOR_VERSION ) ?
MBEDTLS_SSL_MIN_MINOR_VERSION :
MBEDTLS_SSL_MIN_VALID_MINOR_VERSION;
conf->max_major_ver = MBEDTLS_SSL_MAX_MAJOR_VERSION;
conf->max_minor_ver = MBEDTLS_SSL_MAX_MINOR_VERSION;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
conf->min_minor_ver = MBEDTLS_SSL_MINOR_VERSION_2;
#endif
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_0] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_1] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_2] =
conf->ciphersuite_list[MBEDTLS_SSL_MINOR_VERSION_3] =
mbedtls_ssl_list_ciphersuites();
#if defined(MBEDTLS_X509_CRT_PARSE_C)
conf->cert_profile = &mbedtls_x509_crt_profile_default;
#endif
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
conf->sig_hashes = ssl_preset_default_hashes;
#endif
#if defined(MBEDTLS_ECP_C)
conf->curve_list = mbedtls_ecp_grp_id_list();
#endif
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
conf->dhm_min_bitlen = 1024;
#endif
}
return( 0 );
}
/*
* Free mbedtls_ssl_config
*/
void mbedtls_ssl_config_free( mbedtls_ssl_config *conf )
{
#if defined(MBEDTLS_DHM_C)
mbedtls_mpi_free( &conf->dhm_P );
mbedtls_mpi_free( &conf->dhm_G );
#endif
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( conf->psk != NULL )
{
mbedtls_platform_zeroize( conf->psk, conf->psk_len );
mbedtls_free( conf->psk );
conf->psk = NULL;
conf->psk_len = 0;
}
if( conf->psk_identity != NULL )
{
mbedtls_platform_zeroize( conf->psk_identity, conf->psk_identity_len );
mbedtls_free( conf->psk_identity );
conf->psk_identity = NULL;
conf->psk_identity_len = 0;
}
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
ssl_key_cert_free( conf->key_cert );
#endif
mbedtls_platform_zeroize( conf, sizeof( mbedtls_ssl_config ) );
}
#if defined(MBEDTLS_PK_C) && \
( defined(MBEDTLS_RSA_C) || defined(MBEDTLS_ECDSA_C) )
/*
* Convert between MBEDTLS_PK_XXX and SSL_SIG_XXX
*/
unsigned char mbedtls_ssl_sig_from_pk( mbedtls_pk_context *pk )
{
#if defined(MBEDTLS_RSA_C)
if( mbedtls_pk_can_do( pk, MBEDTLS_PK_RSA ) )
return( MBEDTLS_SSL_SIG_RSA );
#endif
#if defined(MBEDTLS_ECDSA_C)
if( mbedtls_pk_can_do( pk, MBEDTLS_PK_ECDSA ) )
return( MBEDTLS_SSL_SIG_ECDSA );
#endif
return( MBEDTLS_SSL_SIG_ANON );
}
unsigned char mbedtls_ssl_sig_from_pk_alg( mbedtls_pk_type_t type )
{
switch( type ) {
case MBEDTLS_PK_RSA:
return( MBEDTLS_SSL_SIG_RSA );
case MBEDTLS_PK_ECDSA:
case MBEDTLS_PK_ECKEY:
return( MBEDTLS_SSL_SIG_ECDSA );
default:
return( MBEDTLS_SSL_SIG_ANON );
}
}
mbedtls_pk_type_t mbedtls_ssl_pk_alg_from_sig( unsigned char sig )
{
switch( sig )
{
#if defined(MBEDTLS_RSA_C)
case MBEDTLS_SSL_SIG_RSA:
return( MBEDTLS_PK_RSA );
#endif
#if defined(MBEDTLS_ECDSA_C)
case MBEDTLS_SSL_SIG_ECDSA:
return( MBEDTLS_PK_ECDSA );
#endif
default:
return( MBEDTLS_PK_NONE );
}
}
#endif /* MBEDTLS_PK_C && ( MBEDTLS_RSA_C || MBEDTLS_ECDSA_C ) */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
/* Find an entry in a signature-hash set matching a given hash algorithm. */
mbedtls_md_type_t mbedtls_ssl_sig_hash_set_find( mbedtls_ssl_sig_hash_set_t *set,
mbedtls_pk_type_t sig_alg )
{
switch( sig_alg )
{
case MBEDTLS_PK_RSA:
return( set->rsa );
case MBEDTLS_PK_ECDSA:
return( set->ecdsa );
default:
return( MBEDTLS_MD_NONE );
}
}
/* Add a signature-hash-pair to a signature-hash set */
void mbedtls_ssl_sig_hash_set_add( mbedtls_ssl_sig_hash_set_t *set,
mbedtls_pk_type_t sig_alg,
mbedtls_md_type_t md_alg )
{
switch( sig_alg )
{
case MBEDTLS_PK_RSA:
if( set->rsa == MBEDTLS_MD_NONE )
set->rsa = md_alg;
break;
case MBEDTLS_PK_ECDSA:
if( set->ecdsa == MBEDTLS_MD_NONE )
set->ecdsa = md_alg;
break;
default:
break;
}
}
/* Allow exactly one hash algorithm for each signature. */
void mbedtls_ssl_sig_hash_set_const_hash( mbedtls_ssl_sig_hash_set_t *set,
mbedtls_md_type_t md_alg )
{
set->rsa = md_alg;
set->ecdsa = md_alg;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2) &&
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
/*
* Convert from MBEDTLS_SSL_HASH_XXX to MBEDTLS_MD_XXX
*/
mbedtls_md_type_t mbedtls_ssl_md_alg_from_hash( unsigned char hash )
{
switch( hash )
{
#if defined(MBEDTLS_MD5_C)
case MBEDTLS_SSL_HASH_MD5:
return( MBEDTLS_MD_MD5 );
#endif
#if defined(MBEDTLS_SHA1_C)
case MBEDTLS_SSL_HASH_SHA1:
return( MBEDTLS_MD_SHA1 );
#endif
#if defined(MBEDTLS_SHA256_C)
case MBEDTLS_SSL_HASH_SHA224:
return( MBEDTLS_MD_SHA224 );
case MBEDTLS_SSL_HASH_SHA256:
return( MBEDTLS_MD_SHA256 );
#endif
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_SSL_HASH_SHA384:
return( MBEDTLS_MD_SHA384 );
case MBEDTLS_SSL_HASH_SHA512:
return( MBEDTLS_MD_SHA512 );
#endif
default:
return( MBEDTLS_MD_NONE );
}
}
/*
* Convert from MBEDTLS_MD_XXX to MBEDTLS_SSL_HASH_XXX
*/
unsigned char mbedtls_ssl_hash_from_md_alg( int md )
{
switch( md )
{
#if defined(MBEDTLS_MD5_C)
case MBEDTLS_MD_MD5:
return( MBEDTLS_SSL_HASH_MD5 );
#endif
#if defined(MBEDTLS_SHA1_C)
case MBEDTLS_MD_SHA1:
return( MBEDTLS_SSL_HASH_SHA1 );
#endif
#if defined(MBEDTLS_SHA256_C)
case MBEDTLS_MD_SHA224:
return( MBEDTLS_SSL_HASH_SHA224 );
case MBEDTLS_MD_SHA256:
return( MBEDTLS_SSL_HASH_SHA256 );
#endif
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_MD_SHA384:
return( MBEDTLS_SSL_HASH_SHA384 );
case MBEDTLS_MD_SHA512:
return( MBEDTLS_SSL_HASH_SHA512 );
#endif
default:
return( MBEDTLS_SSL_HASH_NONE );
}
}
#if defined(MBEDTLS_ECP_C)
/*
* Check if a curve proposed by the peer is in our list.
* Return 0 if we're willing to use it, -1 otherwise.
*/
int mbedtls_ssl_check_curve( const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id )
{
const mbedtls_ecp_group_id *gid;
if( ssl->conf->curve_list == NULL )
return( -1 );
for( gid = ssl->conf->curve_list; *gid != MBEDTLS_ECP_DP_NONE; gid++ )
if( *gid == grp_id )
return( 0 );
return( -1 );
}
#endif /* MBEDTLS_ECP_C */
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
/*
* Check if a hash proposed by the peer is in our list.
* Return 0 if we're willing to use it, -1 otherwise.
*/
int mbedtls_ssl_check_sig_hash( const mbedtls_ssl_context *ssl,
mbedtls_md_type_t md )
{
const int *cur;
if( ssl->conf->sig_hashes == NULL )
return( -1 );
for( cur = ssl->conf->sig_hashes; *cur != MBEDTLS_MD_NONE; cur++ )
if( *cur == (int) md )
return( 0 );
return( -1 );
}
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
int mbedtls_ssl_check_cert_usage( const mbedtls_x509_crt *cert,
const mbedtls_ssl_ciphersuite_t *ciphersuite,
int cert_endpoint,
uint32_t *flags )
{
int ret = 0;
#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
int usage = 0;
#endif
#if defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
const char *ext_oid;
size_t ext_len;
#endif
#if !defined(MBEDTLS_X509_CHECK_KEY_USAGE) && \
!defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
((void) cert);
((void) cert_endpoint);
((void) flags);
#endif
#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
if( cert_endpoint == MBEDTLS_SSL_IS_SERVER )
{
/* Server part of the key exchange */
switch( ciphersuite->key_exchange )
{
case MBEDTLS_KEY_EXCHANGE_RSA:
case MBEDTLS_KEY_EXCHANGE_RSA_PSK:
usage = MBEDTLS_X509_KU_KEY_ENCIPHERMENT;
break;
case MBEDTLS_KEY_EXCHANGE_DHE_RSA:
case MBEDTLS_KEY_EXCHANGE_ECDHE_RSA:
case MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA:
usage = MBEDTLS_X509_KU_DIGITAL_SIGNATURE;
break;
case MBEDTLS_KEY_EXCHANGE_ECDH_RSA:
case MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA:
usage = MBEDTLS_X509_KU_KEY_AGREEMENT;
break;
/* Don't use default: we want warnings when adding new values */
case MBEDTLS_KEY_EXCHANGE_NONE:
case MBEDTLS_KEY_EXCHANGE_PSK:
case MBEDTLS_KEY_EXCHANGE_DHE_PSK:
case MBEDTLS_KEY_EXCHANGE_ECDHE_PSK:
case MBEDTLS_KEY_EXCHANGE_ECJPAKE:
usage = 0;
}
}
else
{
/* Client auth: we only implement rsa_sign and mbedtls_ecdsa_sign for now */
usage = MBEDTLS_X509_KU_DIGITAL_SIGNATURE;
}
if( mbedtls_x509_crt_check_key_usage( cert, usage ) != 0 )
{
*flags |= MBEDTLS_X509_BADCERT_KEY_USAGE;
ret = -1;
}
#else
((void) ciphersuite);
#endif /* MBEDTLS_X509_CHECK_KEY_USAGE */
#if defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
if( cert_endpoint == MBEDTLS_SSL_IS_SERVER )
{
ext_oid = MBEDTLS_OID_SERVER_AUTH;
ext_len = MBEDTLS_OID_SIZE( MBEDTLS_OID_SERVER_AUTH );
}
else
{
ext_oid = MBEDTLS_OID_CLIENT_AUTH;
ext_len = MBEDTLS_OID_SIZE( MBEDTLS_OID_CLIENT_AUTH );
}
if( mbedtls_x509_crt_check_extended_key_usage( cert, ext_oid, ext_len ) != 0 )
{
*flags |= MBEDTLS_X509_BADCERT_EXT_KEY_USAGE;
ret = -1;
}
#endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
return( ret );
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
/*
* Convert version numbers to/from wire format
* and, for DTLS, to/from TLS equivalent.
*
* For TLS this is the identity.
* For DTLS, use 1's complement (v -> 255 - v, and then map as follows:
* 1.0 <-> 3.2 (DTLS 1.0 is based on TLS 1.1)
* 1.x <-> 3.x+1 for x != 0 (DTLS 1.2 based on TLS 1.2)
*/
void mbedtls_ssl_write_version( int major, int minor, int transport,
unsigned char ver[2] )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
if( minor == MBEDTLS_SSL_MINOR_VERSION_2 )
--minor; /* DTLS 1.0 stored as TLS 1.1 internally */
ver[0] = (unsigned char)( 255 - ( major - 2 ) );
ver[1] = (unsigned char)( 255 - ( minor - 1 ) );
}
else
#else
((void) transport);
#endif
{
ver[0] = (unsigned char) major;
ver[1] = (unsigned char) minor;
}
}
void mbedtls_ssl_read_version( int *major, int *minor, int transport,
const unsigned char ver[2] )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
*major = 255 - ver[0] + 2;
*minor = 255 - ver[1] + 1;
if( *minor == MBEDTLS_SSL_MINOR_VERSION_1 )
++*minor; /* DTLS 1.0 stored as TLS 1.1 internally */
}
else
#else
((void) transport);
#endif
{
*major = ver[0];
*minor = ver[1];
}
}
int mbedtls_ssl_set_calc_verify_md( mbedtls_ssl_context *ssl, int md )
{
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 )
return MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH;
switch( md )
{
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1)
#if defined(MBEDTLS_MD5_C)
case MBEDTLS_SSL_HASH_MD5:
return MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH;
#endif
#if defined(MBEDTLS_SHA1_C)
case MBEDTLS_SSL_HASH_SHA1:
ssl->handshake->calc_verify = ssl_calc_verify_tls;
break;
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_SSL_HASH_SHA384:
ssl->handshake->calc_verify = ssl_calc_verify_tls_sha384;
break;
#endif
#if defined(MBEDTLS_SHA256_C)
case MBEDTLS_SSL_HASH_SHA256:
ssl->handshake->calc_verify = ssl_calc_verify_tls_sha256;
break;
#endif
default:
return MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH;
}
return 0;
#else /* !MBEDTLS_SSL_PROTO_TLS1_2 */
(void) ssl;
(void) md;
return MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH;
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
}
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
int mbedtls_ssl_get_key_exchange_md_ssl_tls( mbedtls_ssl_context *ssl,
unsigned char *output,
unsigned char *data, size_t data_len )
{
int ret = 0;
mbedtls_md5_context mbedtls_md5;
mbedtls_sha1_context mbedtls_sha1;
mbedtls_md5_init( &mbedtls_md5 );
mbedtls_sha1_init( &mbedtls_sha1 );
/*
* digitally-signed struct {
* opaque md5_hash[16];
* opaque sha_hash[20];
* };
*
* md5_hash
* MD5(ClientHello.random + ServerHello.random
* + ServerParams);
* sha_hash
* SHA(ClientHello.random + ServerHello.random
* + ServerParams);
*/
if( ( ret = mbedtls_md5_starts_ret( &mbedtls_md5 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md5_starts_ret", ret );
goto exit;
}
if( ( ret = mbedtls_md5_update_ret( &mbedtls_md5,
ssl->handshake->randbytes, 64 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md5_update_ret", ret );
goto exit;
}
if( ( ret = mbedtls_md5_update_ret( &mbedtls_md5, data, data_len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md5_update_ret", ret );
goto exit;
}
if( ( ret = mbedtls_md5_finish_ret( &mbedtls_md5, output ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md5_finish_ret", ret );
goto exit;
}
if( ( ret = mbedtls_sha1_starts_ret( &mbedtls_sha1 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_sha1_starts_ret", ret );
goto exit;
}
if( ( ret = mbedtls_sha1_update_ret( &mbedtls_sha1,
ssl->handshake->randbytes, 64 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_sha1_update_ret", ret );
goto exit;
}
if( ( ret = mbedtls_sha1_update_ret( &mbedtls_sha1, data,
data_len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_sha1_update_ret", ret );
goto exit;
}
if( ( ret = mbedtls_sha1_finish_ret( &mbedtls_sha1,
output + 16 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_sha1_finish_ret", ret );
goto exit;
}
exit:
mbedtls_md5_free( &mbedtls_md5 );
mbedtls_sha1_free( &mbedtls_sha1 );
if( ret != 0 )
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
return( ret );
}
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \
MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_USE_PSA_CRYPTO)
int mbedtls_ssl_get_key_exchange_md_tls1_2( mbedtls_ssl_context *ssl,
unsigned char *hash, size_t *hashlen,
unsigned char *data, size_t data_len,
mbedtls_md_type_t md_alg )
{
psa_status_t status;
psa_hash_operation_t hash_operation = PSA_HASH_OPERATION_INIT;
psa_algorithm_t hash_alg = mbedtls_psa_translate_md( md_alg );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Perform PSA-based computation of digest of ServerKeyExchange" ) );
if( ( status = psa_hash_setup( &hash_operation,
hash_alg ) ) != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_RET( 1, "psa_hash_setup", status );
goto exit;
}
if( ( status = psa_hash_update( &hash_operation, ssl->handshake->randbytes,
64 ) ) != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_RET( 1, "psa_hash_update", status );
goto exit;
}
if( ( status = psa_hash_update( &hash_operation,
data, data_len ) ) != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_RET( 1, "psa_hash_update", status );
goto exit;
}
if( ( status = psa_hash_finish( &hash_operation, hash, MBEDTLS_MD_MAX_SIZE,
hashlen ) ) != PSA_SUCCESS )
{
MBEDTLS_SSL_DEBUG_RET( 1, "psa_hash_finish", status );
goto exit;
}
exit:
if( status != PSA_SUCCESS )
{
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
switch( status )
{
case PSA_ERROR_NOT_SUPPORTED:
return( MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE );
case PSA_ERROR_BAD_STATE: /* Intentional fallthrough */
case PSA_ERROR_BUFFER_TOO_SMALL:
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
case PSA_ERROR_INSUFFICIENT_MEMORY:
return( MBEDTLS_ERR_MD_ALLOC_FAILED );
default:
return( MBEDTLS_ERR_MD_HW_ACCEL_FAILED );
}
}
return( 0 );
}
#else
int mbedtls_ssl_get_key_exchange_md_tls1_2( mbedtls_ssl_context *ssl,
unsigned char *hash, size_t *hashlen,
unsigned char *data, size_t data_len,
mbedtls_md_type_t md_alg )
{
int ret = 0;
mbedtls_md_context_t ctx;
const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_alg );
*hashlen = mbedtls_md_get_size( md_info );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Perform mbedtls-based computation of digest of ServerKeyExchange" ) );
mbedtls_md_init( &ctx );
/*
* digitally-signed struct {
* opaque client_random[32];
* opaque server_random[32];
* ServerDHParams params;
* };
*/
if( ( ret = mbedtls_md_setup( &ctx, md_info, 0 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_setup", ret );
goto exit;
}
if( ( ret = mbedtls_md_starts( &ctx ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_starts", ret );
goto exit;
}
if( ( ret = mbedtls_md_update( &ctx, ssl->handshake->randbytes, 64 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_update", ret );
goto exit;
}
if( ( ret = mbedtls_md_update( &ctx, data, data_len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_update", ret );
goto exit;
}
if( ( ret = mbedtls_md_finish( &ctx, hash ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_finish", ret );
goto exit;
}
exit:
mbedtls_md_free( &ctx );
if( ret != 0 )
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR );
return( ret );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
#endif /* MBEDTLS_SSL_TLS_C */
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