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mbedtls-2.16
mbedtls/library/ssl_tls.c
Rodrigo Dias Correa d2d0e70276 Move declaration to fix C90 warning 
"declaration-after-statement" was generated because that code was
backported from the development branch, which currently uses C99.

Signed-off-by: Rodrigo Dias Correa <rodrigo@correas.us>
2020-11-28 14:59:56 -03:00

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/*
* SSLv3/TLSv1 shared functions
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*
* This file is provided under the Apache License 2.0, or the
* GNU General Public License v2.0 or later.
*
* **********
* Apache License 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.
*
* **********
*
* **********
* GNU General Public License v2.0 or later:
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* **********
*/
/*
* 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/debug.h"
#include "mbedtls/ssl.h"
#include "mbedtls/ssl_internal.h"
#include "mbedtls/platform_util.h"
#include <string.h>
#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,
mbedtls_ssl_transform *transform );
#define SSL_DONT_FORCE_FLUSH 0
#define SSL_FORCE_FLUSH 1
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/* 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 );
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;
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 */
#if defined(MBEDTLS_SSL_CLI_C)
static int 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( src->peer_cert != NULL )
{
int ret;
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 );
}
}
#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 );
}
#endif /* MBEDTLS_SSL_CLI_C */
#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[128];
unsigned char h_i[20];
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
int ret;
mbedtls_md_init( &md_ctx );
if( sizeof( tmp ) < 20 + strlen( label ) + rlen )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
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 )
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
return( ret );
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 )
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
return( ret );
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] );
}
mbedtls_md_free( &md_ctx );
mbedtls_platform_zeroize( tmp, sizeof( tmp ) );
mbedtls_platform_zeroize( h_i, sizeof( h_i ) );
return( 0 );
}
#endif /* MBEDTLS_SSL_PROTO_TLS1) || MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
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[128];
unsigned char h_i[MBEDTLS_MD_MAX_SIZE];
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
int ret;
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 );
if( sizeof( tmp ) < md_len + strlen( label ) + rlen )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
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 )
return( ret );
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];
}
mbedtls_md_free( &md_ctx );
mbedtls_platform_zeroize( tmp, sizeof( tmp ) );
mbedtls_platform_zeroize( h_i, sizeof( h_i ) );
return( 0 );
}
#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( mbedtls_ssl_context *, unsigned char * );
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( mbedtls_ssl_context *, unsigned char * );
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( mbedtls_ssl_context *, unsigned char * );
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( mbedtls_ssl_context *, unsigned char * );
static void ssl_calc_finished_tls_sha384( mbedtls_ssl_context *, unsigned char *, int );
#endif
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl )
{
int ret = 0;
unsigned char tmp[64];
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;
const mbedtls_cipher_info_t *cipher_info;
const mbedtls_md_info_t *md_info;
mbedtls_ssl_session *session = ssl->session_negotiate;
mbedtls_ssl_transform *transform = ssl->transform_negotiate;
mbedtls_ssl_handshake_params *handshake = ssl->handshake;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> derive keys" ) );
cipher_info = mbedtls_cipher_info_from_type( transform->ciphersuite_info->cipher );
if( cipher_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "cipher info for %d not found",
transform->ciphersuite_info->cipher ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
md_info = mbedtls_md_info_from_type( transform->ciphersuite_info->mac );
if( md_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "mbedtls_md info for %d not found",
transform->ciphersuite_info->mac ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/*
* Set appropriate PRF function and other SSL / TLS / TLS1.2 functions
*/
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->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( ssl->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( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
transform->ciphersuite_info->mac == 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( ssl->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 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* SSLv3:
* master =
* MD5( premaster + SHA1( 'A' + premaster + randbytes ) ) +
* MD5( premaster + SHA1( 'BB' + premaster + randbytes ) ) +
* MD5( premaster + SHA1( 'CCC' + premaster + randbytes ) )
*
* TLSv1+:
* master = PRF( premaster, "master secret", randbytes )[0..47]
*/
if( handshake->resume == 0 )
{
MBEDTLS_SSL_DEBUG_BUF( 3, "premaster secret", handshake->premaster,
handshake->pmslen );
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
if( ssl->handshake->extended_ms == MBEDTLS_SSL_EXTENDED_MS_ENABLED )
{
unsigned char session_hash[48];
size_t hash_len;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using extended master secret" ) );
ssl->handshake->calc_verify( ssl, session_hash );
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
#if defined(MBEDTLS_SHA512_C)
if( ssl->transform_negotiate->ciphersuite_info->mac ==
MBEDTLS_MD_SHA384 )
{
hash_len = 48;
}
else
#endif
hash_len = 32;
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
hash_len = 36;
MBEDTLS_SSL_DEBUG_BUF( 3, "session hash", session_hash, hash_len );
ret = handshake->tls_prf( handshake->premaster, handshake->pmslen,
"extended master secret",
session_hash, hash_len,
session->master, 48 );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "prf", ret );
return( ret );
}
}
else
#endif
ret = handshake->tls_prf( handshake->premaster, handshake->pmslen,
"master secret",
handshake->randbytes, 64,
session->master, 48 );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "prf", ret );
return( ret );
}
mbedtls_platform_zeroize( handshake->premaster,
sizeof(handshake->premaster) );
}
else
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no premaster (session resumed)" ) );
/*
* Swap the client and server random values.
*/
memcpy( tmp, handshake->randbytes, 64 );
memcpy( handshake->randbytes, tmp + 32, 32 );
memcpy( handshake->randbytes + 32, tmp, 32 );
mbedtls_platform_zeroize( tmp, sizeof( tmp ) );
/*
* SSLv3:
* key block =
* MD5( master + SHA1( 'A' + master + randbytes ) ) +
* MD5( master + SHA1( 'BB' + master + randbytes ) ) +
* MD5( master + SHA1( 'CCC' + master + randbytes ) ) +
* MD5( master + SHA1( 'DDDD' + master + randbytes ) ) +
* ...
*
* TLSv1:
* key block = PRF( master, "key expansion", randbytes )
*/
ret = handshake->tls_prf( session->master, 48, "key expansion",
handshake->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( session->ciphersuite ) ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "master secret", session->master, 48 );
MBEDTLS_SSL_DEBUG_BUF( 4, "random bytes", handshake->randbytes, 64 );
MBEDTLS_SSL_DEBUG_BUF( 4, "key block", keyblk, 256 );
mbedtls_platform_zeroize( handshake->randbytes,
sizeof( handshake->randbytes ) );
/*
* Determine the appropriate key, IV and MAC length.
*/
transform->keylen = cipher_info->key_bitlen / 8;
if( cipher_info->mode == MBEDTLS_MODE_GCM ||
cipher_info->mode == MBEDTLS_MODE_CCM ||
cipher_info->mode == MBEDTLS_MODE_CHACHAPOLY )
{
size_t taglen, explicit_ivlen;
transform->maclen = 0;
mac_key_len = 0;
/* 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;
/* All modes have 128-bit tags, except CCM_8 (ciphersuite flag) */
taglen = transform->ciphersuite_info->flags &
MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
/* Minimum length of encrypted record */
explicit_ivlen = transform->ivlen - transform->fixed_ivlen;
transform->minlen = explicit_ivlen + taglen;
}
else
{
/* 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 );
return( ret );
}
/* 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( session->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( session->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( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
ssl->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( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_2 ||
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
transform->minlen += transform->ivlen;
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
}
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "keylen: %d, minlen: %d, ivlen: %d, maclen: %d",
transform->keylen, transform->minlen, transform->ivlen,
transform->maclen ) );
/*
* Finally setup the cipher contexts, IVs and MAC secrets.
*/
#if defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
{
key1 = keyblk + mac_key_len * 2;
key2 = keyblk + mac_key_len * 2 + transform->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 + transform->keylen, iv_copy_len );
memcpy( transform->iv_dec, key2 + transform->keylen + iv_copy_len,
iv_copy_len );
}
else
#endif /* MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
{
key1 = keyblk + mac_key_len * 2 + transform->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 + transform->keylen, iv_copy_len );
memcpy( transform->iv_enc, key1 + transform->keylen + iv_copy_len,
iv_copy_len );
}
else
#endif /* MBEDTLS_SSL_SRV_C */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
if( mac_key_len > sizeof transform->mac_enc )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
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( ssl->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" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
if( mbedtls_ssl_hw_record_init != NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_init()" ) );
if( ( ret = mbedtls_ssl_hw_record_init( ssl, key1, key2, transform->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 );
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
}
}
#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,
session->master, keyblk,
mac_key_len, transform->keylen,
iv_copy_len );
}
#endif
if( ( ret = mbedtls_cipher_setup( &transform->cipher_ctx_enc,
cipher_info ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup", ret );
return( ret );
}
if( ( ret = mbedtls_cipher_setup( &transform->cipher_ctx_dec,
cipher_info ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_setup", ret );
return( ret );
}
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 );
return( ret );
}
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 );
return( ret );
}
#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 );
return( ret );
}
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 );
return( ret );
}
}
#endif /* MBEDTLS_CIPHER_MODE_CBC */
mbedtls_platform_zeroize( keyblk, sizeof( keyblk ) );
#if defined(MBEDTLS_ZLIB_SUPPORT)
// Initialize compression
//
if( session->compression == MBEDTLS_SSL_COMPRESS_DEFLATE )
{
if( 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 );
}
}
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" ) );
return( MBEDTLS_ERR_SSL_COMPRESSION_FAILED );
}
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= derive keys" ) );
return( 0 );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
void ssl_calc_verify_ssl( mbedtls_ssl_context *ssl, unsigned char *hash )
{
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 );
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, 36 );
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( mbedtls_ssl_context *ssl, unsigned char *hash )
{
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 );
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, 36 );
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( mbedtls_ssl_context *ssl, unsigned char *hash )
{
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 );
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, 32 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_sha256_free( &sha256 );
return;
}
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
void ssl_calc_verify_tls_sha384( mbedtls_ssl_context *ssl, unsigned char *hash )
{
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 );
MBEDTLS_SSL_DEBUG_BUF( 3, "calculated verify result", hash, 48 );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
mbedtls_sha512_free( &sha512 );
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;
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;
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 */
#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER) || \
defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC)
#define SSL_SOME_MODES_USE_MAC
#endif
/*
* Encryption/decryption functions
*/
static int ssl_encrypt_buf( mbedtls_ssl_context *ssl )
{
mbedtls_cipher_mode_t mode;
int auth_done = 0;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> encrypt buf" ) );
if( ssl->session_out == NULL || ssl->transform_out == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
mode = mbedtls_cipher_get_cipher_mode( &ssl->transform_out->cipher_ctx_enc );
MBEDTLS_SSL_DEBUG_BUF( 4, "before encrypt: output payload",
ssl->out_msg, ssl->out_msglen );
/*
* Add MAC before if needed
*/
#if defined(SSL_SOME_MODES_USE_MAC)
if( mode == MBEDTLS_MODE_STREAM ||
( mode == MBEDTLS_MODE_CBC
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
&& ssl->session_out->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED
#endif
) )
{
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
unsigned char mac[SSL_MAC_MAX_BYTES];
ssl_mac( &ssl->transform_out->md_ctx_enc,
ssl->transform_out->mac_enc,
ssl->out_msg, ssl->out_msglen,
ssl->out_ctr, ssl->out_msgtype,
mac );
memcpy( ssl->out_msg + ssl->out_msglen, mac, ssl->transform_out->maclen );
}
else
#endif
#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 )
{
unsigned char mac[MBEDTLS_SSL_MAC_ADD];
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_ctr, 8 );
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_hdr, 3 );
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_len, 2 );
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc,
ssl->out_msg, ssl->out_msglen );
mbedtls_md_hmac_finish( &ssl->transform_out->md_ctx_enc, mac );
mbedtls_md_hmac_reset( &ssl->transform_out->md_ctx_enc );
memcpy( ssl->out_msg + ssl->out_msglen, mac, ssl->transform_out->maclen );
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "computed mac",
ssl->out_msg + ssl->out_msglen,
ssl->transform_out->maclen );
ssl->out_msglen += ssl->transform_out->maclen;
auth_done++;
}
#endif /* AEAD not the only option */
/*
* Encrypt
*/
#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER)
if( mode == MBEDTLS_MODE_STREAM )
{
int ret;
size_t olen = 0;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of padding",
ssl->out_msglen, 0 ) );
if( ( ret = mbedtls_cipher_crypt( &ssl->transform_out->cipher_ctx_enc,
ssl->transform_out->iv_enc,
ssl->transform_out->ivlen,
ssl->out_msg, ssl->out_msglen,
ssl->out_msg, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( ssl->out_msglen != 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;
size_t enc_msglen, olen;
unsigned char *enc_msg;
unsigned char add_data[13];
unsigned char iv[12];
mbedtls_ssl_transform *transform = ssl->transform_out;
unsigned char taglen = transform->ciphersuite_info->flags &
MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
size_t explicit_ivlen = transform->ivlen - transform->fixed_ivlen;
/*
* Prepare additional authenticated data
*/
memcpy( add_data, ssl->out_ctr, 8 );
add_data[8] = ssl->out_msgtype;
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->conf->transport, add_data + 9 );
add_data[11] = ( ssl->out_msglen >> 8 ) & 0xFF;
add_data[12] = ssl->out_msglen & 0xFF;
MBEDTLS_SSL_DEBUG_BUF( 4, "additional data for AEAD", add_data, 13 );
/*
* 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, ssl->out_ctr, 8 );
memcpy( ssl->out_iv, ssl->out_ctr, 8 );
}
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] ^= ssl->out_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 );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (internal)",
iv, transform->ivlen );
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (transmitted)",
ssl->out_iv, explicit_ivlen );
/*
* Fix message length with added IV
*/
enc_msg = ssl->out_msg;
enc_msglen = ssl->out_msglen;
ssl->out_msglen += explicit_ivlen;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including 0 bytes of padding",
ssl->out_msglen ) );
/*
* Encrypt and authenticate
*/
if( ( ret = mbedtls_cipher_auth_encrypt( &transform->cipher_ctx_enc,
iv, transform->ivlen,
add_data, 13,
enc_msg, enc_msglen,
enc_msg, &olen,
enc_msg + enc_msglen, taglen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_auth_encrypt", ret );
return( ret );
}
if( olen != enc_msglen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl->out_msglen += taglen;
auth_done++;
MBEDTLS_SSL_DEBUG_BUF( 4, "after encrypt: tag", enc_msg + enc_msglen, taglen );
}
else
#endif /* MBEDTLS_GCM_C || MBEDTLS_CCM_C */
#if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC)
if( mode == MBEDTLS_MODE_CBC )
{
int ret;
unsigned char *enc_msg;
size_t enc_msglen, padlen, olen = 0, i;
padlen = ssl->transform_out->ivlen - ( ssl->out_msglen + 1 ) %
ssl->transform_out->ivlen;
if( padlen == ssl->transform_out->ivlen )
padlen = 0;
for( i = 0; i <= padlen; i++ )
ssl->out_msg[ssl->out_msglen + i] = (unsigned char) padlen;
ssl->out_msglen += padlen + 1;
enc_msglen = ssl->out_msglen;
enc_msg = ssl->out_msg;
#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( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
/*
* Generate IV
*/
ret = ssl->conf->f_rng( ssl->conf->p_rng, ssl->transform_out->iv_enc,
ssl->transform_out->ivlen );
if( ret != 0 )
return( ret );
memcpy( ssl->out_iv, ssl->transform_out->iv_enc,
ssl->transform_out->ivlen );
/*
* Fix pointer positions and message length with added IV
*/
enc_msg = ssl->out_msg;
enc_msglen = ssl->out_msglen;
ssl->out_msglen += ssl->transform_out->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",
ssl->out_msglen, ssl->transform_out->ivlen,
padlen + 1 ) );
if( ( ret = mbedtls_cipher_crypt( &ssl->transform_out->cipher_ctx_enc,
ssl->transform_out->iv_enc,
ssl->transform_out->ivlen,
enc_msg, enc_msglen,
enc_msg, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( enc_msglen != 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( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 )
{
/*
* Save IV in SSL3 and TLS1
*/
memcpy( ssl->transform_out->iv_enc,
ssl->transform_out->cipher_ctx_enc.iv,
ssl->transform_out->ivlen );
}
#endif
#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));
*/
unsigned char pseudo_hdr[13];
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using encrypt then mac" ) );
memcpy( pseudo_hdr + 0, ssl->out_ctr, 8 );
memcpy( pseudo_hdr + 8, ssl->out_hdr, 3 );
pseudo_hdr[11] = (unsigned char)( ( ssl->out_msglen >> 8 ) & 0xFF );
pseudo_hdr[12] = (unsigned char)( ( ssl->out_msglen ) & 0xFF );
MBEDTLS_SSL_DEBUG_BUF( 4, "MAC'd meta-data", pseudo_hdr, 13 );
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc, pseudo_hdr, 13 );
mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc,
ssl->out_iv, ssl->out_msglen );
mbedtls_md_hmac_finish( &ssl->transform_out->md_ctx_enc, mac );
mbedtls_md_hmac_reset( &ssl->transform_out->md_ctx_enc );
memcpy( ssl->out_iv + ssl->out_msglen, mac,
ssl->transform_out->maclen );
ssl->out_msglen += ssl->transform_out->maclen;
auth_done++;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
}
else
#endif /* MBEDTLS_SSL_SOME_SUITES_USE_CBC */
{
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 );
}
#if defined(MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC)
/*
* Constant-flow conditional memcpy:
* - if c1 == c2, equivalent to memcpy(dst, src, len),
* - otherwise, a no-op,
* but with execution flow independent of the values of c1 and c2.
*
* Use only bit operations to avoid branches that could be used by some
* compilers on some platforms to translate comparison operators.
*/
static void mbedtls_ssl_cf_memcpy_if_eq( unsigned char *dst,
const unsigned char *src,
size_t len,
size_t c1, size_t c2 )
{
/* diff = 0 if c1 == c2, non-zero otherwise */
const size_t diff = c1 ^ c2;
/* MSVC has a warning about unary minus on unsigned integer types,
* but this is well-defined and precisely what we want to do here. */
#if defined(_MSC_VER)
#pragma warning( push )
#pragma warning( disable : 4146 )
#endif
/* diff_msb's most significant bit is equal to c1 != c2 */
const size_t diff_msb = ( diff | -diff );
/* diff1 = c1 != c2 */
const size_t diff1 = diff_msb >> ( sizeof( diff_msb ) * 8 - 1 );
/* mask = c1 != c2 ? 0xff : 0x00 */
const unsigned char mask = (unsigned char) -diff1;
#if defined(_MSC_VER)
#pragma warning( pop )
#endif
/* dst[i] = c1 != c2 ? dst[i] : src[i] */
size_t i;
for( i = 0; i < len; i++ )
dst[i] = ( dst[i] & mask ) | ( src[i] & ~mask );
}
/*
* Compute HMAC of variable-length data with constant flow.
*
* Only works with MD-5, SHA-1, SHA-256 and SHA-384.
* (Otherwise, computation of block_size needs to be adapted.)
*/
int mbedtls_ssl_cf_hmac(
mbedtls_md_context_t *ctx,
const unsigned char *add_data, size_t add_data_len,
const unsigned char *data, size_t data_len_secret,
size_t min_data_len, size_t max_data_len,
unsigned char *output )
{
/*
* This function breaks the HMAC abstraction and uses the md_clone()
* extension to the MD API in order to get constant-flow behaviour.
*
* HMAC(msg) is defined as HASH(okey + HASH(ikey + msg)) where + means
* concatenation, and okey/ikey are the XOR of the key with some fixed bit
* patterns (see RFC 2104, sec. 2), which are stored in ctx->hmac_ctx.
*
* We'll first compute inner_hash = HASH(ikey + msg) by hashing up to
* minlen, then cloning the context, and for each byte up to maxlen
* finishing up the hash computation, keeping only the correct result.
*
* Then we only need to compute HASH(okey + inner_hash) and we're done.
*/
const mbedtls_md_type_t md_alg = mbedtls_md_get_type( ctx->md_info );
/* TLS 1.0-1.2 only support SHA-384, SHA-256, SHA-1, MD-5,
* all of which have the same block size except SHA-384. */
const size_t block_size = md_alg == MBEDTLS_MD_SHA384 ? 128 : 64;
const unsigned char * const ikey = ctx->hmac_ctx;
const unsigned char * const okey = ikey + block_size;
const size_t hash_size = mbedtls_md_get_size( ctx->md_info );
unsigned char aux_out[MBEDTLS_MD_MAX_SIZE];
mbedtls_md_context_t aux;
size_t offset;
int ret;
mbedtls_md_init( &aux );
#define MD_CHK( func_call ) \
do { \
ret = (func_call); \
if( ret != 0 ) \
goto cleanup; \
} while( 0 )
MD_CHK( mbedtls_md_setup( &aux, ctx->md_info, 0 ) );
/* After hmac_start() of hmac_reset(), ikey has already been hashed,
* so we can start directly with the message */
MD_CHK( mbedtls_md_update( ctx, add_data, add_data_len ) );
MD_CHK( mbedtls_md_update( ctx, data, min_data_len ) );
/* For each possible length, compute the hash up to that point */
for( offset = min_data_len; offset <= max_data_len; offset++ )
{
MD_CHK( mbedtls_md_clone( &aux, ctx ) );
MD_CHK( mbedtls_md_finish( &aux, aux_out ) );
/* Keep only the correct inner_hash in the output buffer */
mbedtls_ssl_cf_memcpy_if_eq( output, aux_out, hash_size,
offset, data_len_secret );
if( offset < max_data_len )
MD_CHK( mbedtls_md_update( ctx, data + offset, 1 ) );
}
/* Now compute HASH(okey + inner_hash) */
MD_CHK( mbedtls_md_starts( ctx ) );
MD_CHK( mbedtls_md_update( ctx, okey, block_size ) );
MD_CHK( mbedtls_md_update( ctx, output, hash_size ) );
MD_CHK( mbedtls_md_finish( ctx, output ) );
/* Done, get ready for next time */
MD_CHK( mbedtls_md_hmac_reset( ctx ) );
#undef MD_CHK
cleanup:
mbedtls_md_free( &aux );
return( ret );
}
/*
* Constant-flow memcpy from variable position in buffer.
* - functionally equivalent to memcpy(dst, src + offset_secret, len)
* - but with execution flow independent from the value of offset_secret.
*/
void mbedtls_ssl_cf_memcpy_offset( unsigned char *dst,
const unsigned char *src_base,
size_t offset_secret,
size_t offset_min, size_t offset_max,
size_t len )
{
size_t offset;
for( offset = offset_min; offset <= offset_max; offset++ )
{
mbedtls_ssl_cf_memcpy_if_eq( dst, src_base + offset, len,
offset, offset_secret );
}
}
#endif /* MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC */
static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
{
mbedtls_cipher_mode_t mode;
int auth_done = 0;
#if defined(SSL_SOME_MODES_USE_MAC)
size_t padlen = 0, correct = 1;
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> decrypt buf" ) );
if( ssl->session_in == NULL || ssl->transform_in == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
mode = mbedtls_cipher_get_cipher_mode( &ssl->transform_in->cipher_ctx_dec );
if( ssl->in_msglen < ssl->transform_in->minlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "in_msglen (%d) < minlen (%d)",
ssl->in_msglen, ssl->transform_in->minlen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER)
if( mode == MBEDTLS_MODE_STREAM )
{
int ret;
size_t olen = 0;
padlen = 0;
if( ( ret = mbedtls_cipher_crypt( &ssl->transform_in->cipher_ctx_dec,
ssl->transform_in->iv_dec,
ssl->transform_in->ivlen,
ssl->in_msg, ssl->in_msglen,
ssl->in_msg, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( ssl->in_msglen != 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;
size_t dec_msglen, olen;
unsigned char *dec_msg;
unsigned char *dec_msg_result;
unsigned char add_data[13];
unsigned char iv[12];
mbedtls_ssl_transform *transform = ssl->transform_in;
unsigned char taglen = transform->ciphersuite_info->flags &
MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
size_t explicit_iv_len = transform->ivlen - transform->fixed_ivlen;
/*
* Compute and update sizes
*/
if( ssl->in_msglen < explicit_iv_len + taglen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < explicit_iv_len (%d) "
"+ taglen (%d)", ssl->in_msglen,
explicit_iv_len, taglen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
dec_msglen = ssl->in_msglen - explicit_iv_len - taglen;
dec_msg = ssl->in_msg;
dec_msg_result = ssl->in_msg;
ssl->in_msglen = dec_msglen;
/*
* Prepare additional authenticated data
*/
memcpy( add_data, ssl->in_ctr, 8 );
add_data[8] = ssl->in_msgtype;
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->conf->transport, add_data + 9 );
add_data[11] = ( ssl->in_msglen >> 8 ) & 0xFF;
add_data[12] = ssl->in_msglen & 0xFF;
MBEDTLS_SSL_DEBUG_BUF( 4, "additional data for AEAD", add_data, 13 );
/*
* Prepare IV
*/
if( transform->ivlen == 12 && transform->fixed_ivlen == 4 )
{
/* GCM and CCM: fixed || explicit (transmitted) */
memcpy( iv, transform->iv_dec, transform->fixed_ivlen );
memcpy( iv + transform->fixed_ivlen, ssl->in_iv, 8 );
}
else 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] ^= ssl->in_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 );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "IV used", iv, transform->ivlen );
MBEDTLS_SSL_DEBUG_BUF( 4, "TAG used", dec_msg + dec_msglen, taglen );
/*
* Decrypt and authenticate
*/
if( ( ret = mbedtls_cipher_auth_decrypt( &ssl->transform_in->cipher_ctx_dec,
iv, transform->ivlen,
add_data, 13,
dec_msg, dec_msglen,
dec_msg_result, &olen,
dec_msg + dec_msglen, 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++;
if( olen != dec_msglen )
{
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_SSL_SOME_SUITES_USE_CBC)
if( mode == MBEDTLS_MODE_CBC )
{
/*
* Decrypt and check the padding
*/
int ret;
unsigned char *dec_msg;
unsigned char *dec_msg_result;
size_t dec_msglen;
size_t minlen = 0;
size_t olen = 0;
/*
* Check immediate ciphertext sanity
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
minlen += ssl->transform_in->ivlen;
#endif
if( ssl->in_msglen < minlen + ssl->transform_in->ivlen ||
ssl->in_msglen < minlen + ssl->transform_in->maclen + 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < max( ivlen(%d), maclen (%d) "
"+ 1 ) ( + expl IV )", ssl->in_msglen,
ssl->transform_in->ivlen,
ssl->transform_in->maclen ) );
return( MBEDTLS_ERR_SSL_INVALID_MAC );
}
dec_msglen = ssl->in_msglen;
dec_msg = ssl->in_msg;
dec_msg_result = ssl->in_msg;
/*
* Authenticate before decrypt if enabled
*/
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if( ssl->session_in->encrypt_then_mac == MBEDTLS_SSL_ETM_ENABLED )
{
unsigned char mac_expect[MBEDTLS_SSL_MAC_ADD];
unsigned char pseudo_hdr[13];
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using encrypt then mac" ) );
dec_msglen -= ssl->transform_in->maclen;
ssl->in_msglen -= ssl->transform_in->maclen;
memcpy( pseudo_hdr + 0, ssl->in_ctr, 8 );
memcpy( pseudo_hdr + 8, ssl->in_hdr, 3 );
pseudo_hdr[11] = (unsigned char)( ( ssl->in_msglen >> 8 ) & 0xFF );
pseudo_hdr[12] = (unsigned char)( ( ssl->in_msglen ) & 0xFF );
MBEDTLS_SSL_DEBUG_BUF( 4, "MAC'd meta-data", pseudo_hdr, 13 );
mbedtls_md_hmac_update( &ssl->transform_in->md_ctx_dec, pseudo_hdr, 13 );
mbedtls_md_hmac_update( &ssl->transform_in->md_ctx_dec,
ssl->in_iv, ssl->in_msglen );
mbedtls_md_hmac_finish( &ssl->transform_in->md_ctx_dec, mac_expect );
mbedtls_md_hmac_reset( &ssl->transform_in->md_ctx_dec );
MBEDTLS_SSL_DEBUG_BUF( 4, "message mac", ssl->in_iv + ssl->in_msglen,
ssl->transform_in->maclen );
MBEDTLS_SSL_DEBUG_BUF( 4, "expected mac", mac_expect,
ssl->transform_in->maclen );
if( mbedtls_ssl_safer_memcmp( ssl->in_iv + ssl->in_msglen, mac_expect,
ssl->transform_in->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
*/
if( ssl->in_msglen % ssl->transform_in->ivlen != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) %% ivlen (%d) != 0",
ssl->in_msglen, ssl->transform_in->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( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
unsigned char i;
dec_msglen -= ssl->transform_in->ivlen;
ssl->in_msglen -= ssl->transform_in->ivlen;
for( i = 0; i < ssl->transform_in->ivlen; i++ )
ssl->transform_in->iv_dec[i] = ssl->in_iv[i];
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
if( ( ret = mbedtls_cipher_crypt( &ssl->transform_in->cipher_ctx_dec,
ssl->transform_in->iv_dec,
ssl->transform_in->ivlen,
dec_msg, dec_msglen,
dec_msg_result, &olen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_cipher_crypt", ret );
return( ret );
}
if( dec_msglen != 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( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 )
{
/*
* Save IV in SSL3 and TLS1
*/
memcpy( ssl->transform_in->iv_dec,
ssl->transform_in->cipher_ctx_dec.iv,
ssl->transform_in->ivlen );
}
#endif
padlen = 1 + ssl->in_msg[ssl->in_msglen - 1];
if( ssl->in_msglen < ssl->transform_in->maclen + padlen &&
auth_done == 0 )
{
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < maclen (%d) + padlen (%d)",
ssl->in_msglen, ssl->transform_in->maclen, padlen ) );
#endif
padlen = 0;
correct = 0;
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
if( padlen > ssl->transform_in->ivlen )
{
#if defined(MBEDTLS_SSL_DEBUG_ALL)
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad padding length: is %d, "
"should be no more than %d",
padlen, ssl->transform_in->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( ssl->minor_ver > MBEDTLS_SSL_MINOR_VERSION_0 )
{
/*
* TLSv1+: always check the padding up to the first failure
* and fake check up to 256 bytes of padding
*/
size_t pad_count = 0, real_count = 1;
size_t padding_idx = ssl->in_msglen - padlen;
size_t i;
/*
* Padding is guaranteed to be incorrect if:
* 1. padlen > ssl->in_msglen
*
* 2. padding_idx > MBEDTLS_SSL_IN_CONTENT_LEN +
* ssl->transform_in->maclen
*
* In both cases we reset padding_idx to a safe value (0) to
* prevent out-of-buffer reads.
*/
correct &= ( padlen <= ssl->in_msglen );
correct &= ( padding_idx <= MBEDTLS_SSL_IN_CONTENT_LEN +
ssl->transform_in->maclen );
padding_idx *= correct;
for( i = 0; i < 256; i++ )
{
real_count &= ( i < padlen );
pad_count += real_count *
( ssl->in_msg[padding_idx + i] == padlen - 1 );
}
correct &= ( pad_count == padlen ); /* Only 1 on correct padding */
#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 );
}
ssl->in_msglen -= padlen;
}
else
#endif /* MBEDTLS_SSL_SOME_SUITES_USE_CBC) */
{
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",
ssl->in_msg, ssl->in_msglen );
#endif
/*
* Authenticate if not done yet.
* Compute the MAC regardless of the padding result (RFC4346, CBCTIME).
*/
#if defined(SSL_SOME_MODES_USE_MAC)
if( auth_done == 0 )
{
unsigned char mac_expect[MBEDTLS_SSL_MAC_ADD];
unsigned char mac_peer[MBEDTLS_SSL_MAC_ADD];
ssl->in_msglen -= ssl->transform_in->maclen;
ssl->in_len[0] = (unsigned char)( ssl->in_msglen >> 8 );
ssl->in_len[1] = (unsigned char)( ssl->in_msglen );
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
ssl_mac( &ssl->transform_in->md_ctx_dec,
ssl->transform_in->mac_dec,
ssl->in_msg, ssl->in_msglen,
ssl->in_ctr, ssl->in_msgtype,
mac_expect );
memcpy( mac_peer, ssl->in_msg + ssl->in_msglen,
ssl->transform_in->maclen );
}
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_0 )
{
int ret;
unsigned char add_data[13];
/*
* 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
* in_msglen -= 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 = ssl->in_msglen + padlen;
const size_t min_len = ( max_len > 256 ) ? max_len - 256 : 0;
memcpy( add_data + 0, ssl->in_ctr, 8 );
memcpy( add_data + 8, ssl->in_hdr, 3 );
memcpy( add_data + 11, ssl->in_len, 2 );
ret = mbedtls_ssl_cf_hmac( &ssl->transform_in->md_ctx_dec,
add_data, sizeof( add_data ),
ssl->in_msg, ssl->in_msglen,
min_len, max_len,
mac_expect );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_cf_hmac", ret );
return( ret );
}
mbedtls_ssl_cf_memcpy_offset( mac_peer, ssl->in_msg,
ssl->in_msglen,
min_len, max_len,
ssl->transform_in->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, ssl->transform_in->maclen );
MBEDTLS_SSL_DEBUG_BUF( 4, "message mac", mac_peer, ssl->transform_in->maclen );
#endif
if( mbedtls_ssl_safer_memcmp( mac_peer, mac_expect,
ssl->transform_in->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 /* 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( ssl->in_msglen == 0 )
{
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3
&& ssl->in_msgtype != 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" ) );
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 char 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 );
}
}
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;
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;
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;
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 > (int)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;
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_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 > (int)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 int ssl_swap_epochs( mbedtls_ssl_context *ssl )
{
mbedtls_ssl_transform *tmp_transform;
unsigned char tmp_out_ctr[8];
#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
int ret;
#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
if( ssl->transform_out == ssl->handshake->alt_transform_out )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip swap epochs" ) );
return( 0 );
}
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 /* MBEDTLS_SSL_HW_RECORD_ACCEL */
return( 0 );
}
/*
* 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_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;
if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
return( ret );
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" ) );
if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
return( ret );
}
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 )
{
if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
return( ret );
}
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;
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;
ssl->out_hdr[0] = (unsigned char) ssl->out_msgtype;
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 )
{
if( ( ret = ssl_encrypt_buf( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_encrypt_buf", ret );
return( ret );
}
len = ssl->out_msglen;
ssl->out_len[0] = (unsigned char)( len >> 8 );
ssl->out_len[1] = (unsigned char)( len );
}
protected_record_size = len + mbedtls_ssl_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 */
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;
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] ) );
}
/*
* Return 0 if sequence number is acceptable, -1 otherwise
*/
int mbedtls_ssl_dtls_replay_check( mbedtls_ssl_context *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;
if( f_cookie_write == NULL || f_cookie_check == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
/*
* 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;
size_t len;
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 )
{
int send_ret;
MBEDTLS_SSL_DEBUG_MSG( 1, ( "sending HelloVerifyRequest" ) );
MBEDTLS_SSL_DEBUG_BUF( 4, "output record sent to network",
ssl->out_buf, len );
/* 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. */
send_ret = ssl->f_send( ssl->p_bio, ssl->out_buf, len );
MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_send", send_ret );
(void) send_ret;
return( MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED );
}
if( ret == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "cookie is valid, resetting 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 */
/*
* 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 *ssl )
{
int major_ver, minor_ver;
MBEDTLS_SSL_DEBUG_BUF( 4, "input record header", ssl->in_hdr, mbedtls_ssl_hdr_len( ssl ) );
ssl->in_msgtype = ssl->in_hdr[0];
ssl->in_msglen = ( ssl->in_len[0] << 8 ) | ssl->in_len[1];
mbedtls_ssl_read_version( &major_ver, &minor_ver, ssl->conf->transport, ssl->in_hdr + 1 );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "input record: msgtype = %d, "
"version = [%d:%d], msglen = %d",
ssl->in_msgtype,
major_ver, minor_ver, ssl->in_msglen ) );
/* Check record type */
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE &&
ssl->in_msgtype != MBEDTLS_SSL_MSG_ALERT &&
ssl->in_msgtype != MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC &&
ssl->in_msgtype != MBEDTLS_SSL_MSG_APPLICATION_DATA )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "unknown record type" ) );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/* Silently ignore invalid DTLS records as recommended by RFC 6347
* Section 4.1.2.7 */
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM )
#endif /* MBEDTLS_SSL_PROTO_DTLS */
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
/* Check version */
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 );
}
/* Check length against the size of our buffer */
if( ssl->in_msglen > MBEDTLS_SSL_IN_BUFFER_LEN
- (size_t)( ssl->in_msg - ssl->in_buf ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
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 )
{
unsigned int rec_epoch = ( ssl->in_ctr[0] << 8 ) | ssl->in_ctr[1];
/* Check epoch (and sequence number) with DTLS */
if( rec_epoch != ssl->in_epoch )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "record from another epoch: "
"expected %d, received %d",
ssl->in_epoch, rec_epoch ) );
#if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE) && defined(MBEDTLS_SSL_SRV_C)
/*
* 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( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER &&
rec_epoch == 0 &&
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 ) );
}
else
#endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE && MBEDTLS_SSL_SRV_C */
{
/* Consider buffering the record. */
if( rec_epoch == (unsigned int) 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)
/* Replay detection only works for the current epoch */
if( rec_epoch == ssl->in_epoch &&
mbedtls_ssl_dtls_replay_check( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "replayed record" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_RECORD );
}
#endif
/* 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_UNEXPECTED_RECORD );
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* Check length against bounds of the current transform and version */
if( ssl->transform_in == NULL )
{
if( ssl->in_msglen < 1 ||
ssl->in_msglen > MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
}
else
{
if( ssl->in_msglen < ssl->transform_in->minlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#if defined(MBEDTLS_SSL_PROTO_SSL3)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 &&
ssl->in_msglen > ssl->transform_in->minlen + MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
/*
* TLS encrypted messages can have up to 256 bytes of padding
*/
if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_1 &&
ssl->in_msglen > ssl->transform_in->minlen +
MBEDTLS_SSL_IN_CONTENT_LEN + 256 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
#endif
}
return( 0 );
}
/*
* If applicable, decrypt (and decompress) record content
*/
static int ssl_prepare_record_content( mbedtls_ssl_context *ssl )
{
int ret, done = 0;
MBEDTLS_SSL_DEBUG_BUF( 4, "input record from network",
ssl->in_hdr, mbedtls_ssl_hdr_len( ssl ) + ssl->in_msglen );
#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 )
{
if( ( ret = ssl_decrypt_buf( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_decrypt_buf", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_BUF( 4, "input payload after decrypt",
ssl->in_msg, ssl->in_msglen );
if( ssl->in_msglen > MBEDTLS_SSL_IN_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( MBEDTLS_ERR_SSL_INVALID_RECORD );
}
}
#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 );
}
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
mbedtls_ssl_dtls_replay_update( ssl );
}
#endif
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_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_ssl_handshake_params * const hs = ssl->handshake;
size_t const rec_hdr_len = 13;
size_t const total_buf_sz = rec_hdr_len + ssl->in_msglen;
/* Don't buffer future records outside handshakes. */
if( hs == NULL )
return( 0 );
/* Only buffer handshake records (we are only interested
* in Finished messages). */
if( ssl->in_msgtype != 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( total_buf_sz > ( 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) total_buf_sz, 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", ssl->in_hdr,
rec_hdr_len + ssl->in_msglen );
/* 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 = total_buf_sz;
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, ssl->in_hdr, total_buf_sz );
hs->buffering.total_bytes_buffered += total_buf_sz;
return( 0 );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static int ssl_get_next_record( mbedtls_ssl_context *ssl )
{
int ret;
#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 */
if( ( ret = mbedtls_ssl_fetch_input( ssl, mbedtls_ssl_hdr_len( ssl ) ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret );
return( ret );
}
if( ( ret = ssl_parse_record_header( ssl ) ) != 0 )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ret != MBEDTLS_ERR_SSL_CLIENT_RECONNECT )
{
if( ret == MBEDTLS_ERR_SSL_EARLY_MESSAGE )
{
ret = ssl_buffer_future_record( ssl );
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 )
{
/* Skip unexpected record (but not whole datagram) */
ssl->next_record_offset = ssl->in_msglen
+ mbedtls_ssl_hdr_len( ssl );
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 );
}
#endif
return( ret );
}
/*
* Read and optionally decrypt the message contents
*/
if( ( ret = mbedtls_ssl_fetch_input( ssl,
mbedtls_ssl_hdr_len( ssl ) + ssl->in_msglen ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret );
return( ret );
}
/* Done reading this record, get ready for the next one */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->next_record_offset = ssl->in_msglen + mbedtls_ssl_hdr_len( ssl );
if( ssl->next_record_offset < ssl->in_left )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "more than one record within datagram" ) );
}
}
else
#endif
ssl->in_left = 0;
if( ( ret = ssl_prepare_record_content( ssl ) ) != 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_RECORD ||
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 );
}
}
return( 0 );
}
int mbedtls_ssl_handle_message_type( mbedtls_ssl_context *ssl )
{
int ret;
/*
* 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 &&
ssl->handshake != NULL &&
ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER )
{
ssl_handshake_wrapup_free_hs_transform( ssl );
}
#endif
return( 0 );
}
int mbedtls_ssl_send_fatal_handshake_failure( mbedtls_ssl_context *ssl )
{
int ret;
if( ( ret = mbedtls_ssl_send_alert_message( ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
unsigned char level,
unsigned char message )
{
int ret;
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 );
}
/*
* Handshake functions
*/
#if !defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
/* No certificate support -> dummy functions */
int mbedtls_ssl_write_certificate( mbedtls_ssl_context *ssl )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
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->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
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
/* 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->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
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 );
}
/*
* 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 )
{
int ret;
size_t i, n;
uint8_t alert;
#if defined(MBEDTLS_SSL_SRV_C)
#if defined(MBEDTLS_SSL_PROTO_SSL3)
/*
* Check if the client sent an empty certificate
*/
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
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" ) );
/* The client was asked for a certificate but didn't send
one. The client should know what's going on, so we
don't send an alert. */
ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_MISSING;
return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
}
}
#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->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_0 )
{
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" ) );
/* The client was asked for a certificate but didn't send
one. The client should know what's going on, so we
don't send an alert. */
ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_MISSING;
return( MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE );
}
}
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
#endif /* MBEDTLS_SSL_SRV_C */
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 );
}
/* In case we tried to reuse a session but it failed */
if( ssl->session_negotiate->peer_cert != NULL )
{
mbedtls_x509_crt_free( ssl->session_negotiate->peer_cert );
mbedtls_free( ssl->session_negotiate->peer_cert );
}
if( ( ssl->session_negotiate->peer_cert = mbedtls_calloc( 1,
sizeof( mbedtls_x509_crt ) ) ) == 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 );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
mbedtls_x509_crt_init( ssl->session_negotiate->peer_cert );
i += 3;
while( i < ssl->in_hslen )
{
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 );
}
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 );
}
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 );
}
ret = mbedtls_x509_crt_parse_der( ssl->session_negotiate->peer_cert,
ssl->in_msg + i, n );
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", ssl->session_negotiate->peer_cert );
/*
* On client, make sure the server cert doesn't change during renego to
* avoid "triple handshake" attack: https://secure-resumption.com/
*/
#if defined(MBEDTLS_SSL_RENEGOTIATION) && defined(MBEDTLS_SSL_CLI_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT &&
ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
{
if( ssl->session->peer_cert == NULL )
{
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 );
}
if( ssl->session->peer_cert->raw.len !=
ssl->session_negotiate->peer_cert->raw.len ||
memcmp( ssl->session->peer_cert->raw.p,
ssl->session_negotiate->peer_cert->raw.p,
ssl->session->peer_cert->raw.len ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server cert changed 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 );
}
}
#endif /* MBEDTLS_SSL_RENEGOTIATION && MBEDTLS_SSL_CLI_C */
return( 0 );
}
int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl )
{
int ret;
const mbedtls_ssl_ciphersuite_t * const ciphersuite_info =
ssl->transform_negotiate->ciphersuite_info;
#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_SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(MBEDTLS_SSL_SRV_C)
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER &&
authmode == MBEDTLS_SSL_VERIFY_NONE )
{
ssl->session_negotiate->verify_result = MBEDTLS_X509_BADCERT_SKIP_VERIFY;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
#endif
#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
if( ssl->handshake->ecrs_enabled &&
ssl->handshake->ecrs_state == ssl_ecrs_crt_verify )
{
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 );
return( ret );
}
if( ( ret = ssl_parse_certificate_chain( ssl ) ) != 0 )
{
#if defined(MBEDTLS_SSL_SRV_C)
if( ret == MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE &&
authmode == MBEDTLS_SSL_VERIFY_OPTIONAL )
{
ret = 0;
}
#endif
ssl->state++;
return( ret );
}
#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
if( authmode != MBEDTLS_SSL_VERIFY_NONE )
{
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;
}
/*
* Main check: verify certificate
*/
ret = mbedtls_x509_crt_verify_restartable(
ssl->session_negotiate->peer_cert,
ca_chain, ca_crl,
ssl->conf->cert_profile,
ssl->hostname,
&ssl->session_negotiate->verify_result,
ssl->conf->f_vrfy, ssl->conf->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 = &ssl->session_negotiate->peer_cert->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( ssl->session_negotiate->peer_cert,
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( ca_chain == NULL && 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 */
}
ssl->state++;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate" ) );
return( ret );
}
#endif /* !MBEDTLS_KEY_EXCHANGE_RSA_ENABLED
!MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED
!MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED
!MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED
!MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
!MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED
!MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
int mbedtls_ssl_write_change_cipher_spec( mbedtls_ssl_context *ssl )
{
int ret;
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_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, ssl->transform_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_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)
mbedtls_sha256_starts_ret( &ssl->handshake->fin_sha256, 0 );
#endif
#if defined(MBEDTLS_SHA512_C)
mbedtls_sha512_starts_ret( &ssl->handshake->fin_sha512, 1 );
#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)
mbedtls_sha256_update_ret( &ssl->handshake->fin_sha256, buf, len );
#endif
#if defined(MBEDTLS_SHA512_C)
mbedtls_sha512_update_ret( &ssl->handshake->fin_sha512, buf, len );
#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 )
{
mbedtls_sha256_update_ret( &ssl->handshake->fin_sha256, buf, len );
}
#endif
#if defined(MBEDTLS_SHA512_C)
static void ssl_update_checksum_sha384( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
mbedtls_sha512_update_ret( &ssl->handshake->fin_sha512, buf, len );
}
#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;
mbedtls_sha256_context sha256;
unsigned char padbuf[32];
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
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
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
mbedtls_sha256_finish_ret( &sha256, padbuf );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 32, buf, len );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
mbedtls_sha256_free( &sha256 );
mbedtls_platform_zeroize( padbuf, sizeof( padbuf ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
typedef int (*finish_sha384_t)(mbedtls_sha512_context*, unsigned char*);
static void ssl_calc_finished_tls_sha384(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
mbedtls_sha512_context sha512;
unsigned char padbuf[48];
/*
* For SHA-384, we can save 16 bytes by keeping padbuf 48 bytes long.
* However, to avoid stringop-overflow warning in gcc, we have to cast
* mbedtls_sha512_finish_ret().
*/
finish_sha384_t finish_sha384 = (finish_sha384_t)mbedtls_sha512_finish_ret;
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
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
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
finish_sha384( &sha512, padbuf );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 48, buf, len );
MBEDTLS_SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
mbedtls_sha512_free( &sha512 );
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;
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)
mbedtls_sha256_init( &handshake->fin_sha256 );
mbedtls_sha256_starts_ret( &handshake->fin_sha256, 0 );
#endif
#if defined(MBEDTLS_SHA512_C)
mbedtls_sha512_init( &handshake->fin_sha512 );
mbedtls_sha512_starts_ret( &handshake->fin_sha512, 1 );
#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
}
static void 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 );
mbedtls_md_init( &transform->md_ctx_enc );
mbedtls_md_init( &transform->md_ctx_dec );
}
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 );
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;
ssl->out_len = ssl->out_hdr + 11;
ssl->out_iv = ssl->out_hdr + 13;
}
else
#endif
{
ssl->out_ctr = ssl->out_hdr - 8;
ssl->out_len = ssl->out_hdr + 3;
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,
mbedtls_ssl_transform *transform )
{
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
ssl->in_ctr = ssl->in_hdr + 3;
ssl->in_len = ssl->in_hdr + 11;
ssl->in_iv = ssl->in_hdr + 13;
}
else
#endif
{
ssl->in_ctr = ssl->in_hdr - 8;
ssl->in_len = ssl->in_hdr + 3;
ssl->in_iv = ssl->in_hdr + 5;
}
/* Offset in_msg from in_iv to allow space for explicit IV, if used. */
if( transform != NULL &&
ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
{
ssl->in_msg = ssl->in_iv + transform->ivlen - transform->fixed_ivlen;
}
else
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, NULL /* no transform enabled */ );
}
int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
const mbedtls_ssl_config *conf )
{
int ret;
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;
#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;
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 = 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;
}
#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_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)
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 )
{
if( psk == NULL || psk_identity == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
if( psk_len > MBEDTLS_PSK_MAX_LEN )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
/* Identity len will be encoded on two bytes */
if( ( psk_identity_len >> 16 ) != 0 ||
psk_identity_len > MBEDTLS_SSL_OUT_CONTENT_LEN )
{
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
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_free( conf->psk_identity );
conf->psk_identity = NULL;
conf->psk_identity_len = 0;
}
if( ( conf->psk = mbedtls_calloc( 1, psk_len ) ) == NULL ||
( conf->psk_identity = mbedtls_calloc( 1, psk_identity_len ) ) == NULL )
{
mbedtls_free( conf->psk );
mbedtls_free( conf->psk_identity );
conf->psk = NULL;
conf->psk_identity = NULL;
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
conf->psk_len = psk_len;
conf->psk_identity_len = psk_identity_len;
memcpy( conf->psk, psk, conf->psk_len );
memcpy( conf->psk_identity, psk_identity, conf->psk_identity_len );
return( 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 );
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;
}
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 );
}
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;
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;
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;
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 > MBEDTLS_SSL_MAX_ALPN_NAME_LEN ) ||
( tot_len > MBEDTLS_SSL_MAX_ALPN_LIST_LEN ) )
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;
}
#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;
if( transform == NULL )
return( (int) mbedtls_ssl_hdr_len( ssl ) );
#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 );
}
return( (int)( mbedtls_ssl_hdr_len( ssl ) + 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 );
return( ssl->session->peer_cert );
}
#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( ssl_session_copy( dst, ssl->session ) );
}
#endif /* MBEDTLS_SSL_CLI_C */
/*
* 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_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_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;
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;
/* Zeroising the plaintext buffer to erase unused application data
from the memory. */
mbedtls_platform_zeroize( ssl->in_offt, 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;
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_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;
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 );
mbedtls_md_free( &transform->md_ctx_enc );
mbedtls_md_free( &transform->md_ctx_dec );
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)
mbedtls_sha256_free( &handshake->fin_sha256 );
#endif
#if defined(MBEDTLS_SHA512_C)
mbedtls_sha512_free( &handshake->fin_sha512 );
#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 );
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
mbedtls_free( handshake->verify_cookie );
ssl_flight_free( handshake->flight );
ssl_buffering_free( ssl );
#endif
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)
if( session->peer_cert != NULL )
{
mbedtls_x509_crt_free( session->peer_cert );
mbedtls_free( session->peer_cert );
}
#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 ) );
}
/*
* 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;
#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)
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_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_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
#endif /* MBEDTLS_SSL_TLS_C */
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