mbedtls/library/ssl_tls.c
Paul Bakker 0a971b5dc8 Removed further timing differences during SSL message decryption in ssl_decrypt_buf()
New padding checking is unbiased on correct or incorrect padding and
has no branch prediction timing differences.

The additional MAC checks further straighten out the timing differences.
(cherry picked from commit e47b34bdc8)

Conflicts:
	ChangeLog
	library/ssl_tls.c
2013-03-11 16:08:06 +01:00

2400 lines
65 KiB
C

/*
* SSLv3/TLSv1 shared functions
*
* Copyright (C) 2006-2010, Brainspark B.V.
*
* This file is part of PolarSSL (http://www.polarssl.org)
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
*
* All rights reserved.
*
* 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
*/
#include "polarssl/config.h"
#if defined(POLARSSL_SSL_TLS_C)
#include "polarssl/aes.h"
#include "polarssl/arc4.h"
#include "polarssl/camellia.h"
#include "polarssl/des.h"
#include "polarssl/debug.h"
#include "polarssl/ssl.h"
#include <stdlib.h>
#include <time.h>
#if defined _MSC_VER && !defined strcasecmp
#define strcasecmp _stricmp
#endif
/*
* Key material generation
*/
static int tls1_prf( unsigned char *secret, size_t slen, char *label,
unsigned char *random, size_t rlen,
unsigned char *dstbuf, size_t dlen )
{
size_t nb, hs;
size_t i, j, k;
unsigned char *S1, *S2;
unsigned char tmp[128];
unsigned char h_i[20];
if( sizeof( tmp ) < 20 + strlen( label ) + rlen )
return( POLARSSL_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]
*/
md5_hmac( S1, hs, tmp + 20, nb, 4 + tmp );
for( i = 0; i < dlen; i += 16 )
{
md5_hmac( S1, hs, 4 + tmp, 16 + nb, h_i );
md5_hmac( S1, hs, 4 + tmp, 16, 4 + tmp );
k = ( i + 16 > dlen ) ? dlen % 16 : 16;
for( j = 0; j < k; j++ )
dstbuf[i + j] = h_i[j];
}
/*
* XOR out with P_sha1(secret,label+random)[0..dlen]
*/
sha1_hmac( S2, hs, tmp + 20, nb, tmp );
for( i = 0; i < dlen; i += 20 )
{
sha1_hmac( S2, hs, tmp, 20 + nb, h_i );
sha1_hmac( S2, hs, tmp, 20, 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] );
}
memset( tmp, 0, sizeof( tmp ) );
memset( h_i, 0, sizeof( h_i ) );
return( 0 );
}
int ssl_derive_keys( ssl_context *ssl )
{
int i;
md5_context md5;
sha1_context sha1;
unsigned char tmp[64];
unsigned char padding[16];
unsigned char sha1sum[20];
unsigned char keyblk[256];
unsigned char *key1;
unsigned char *key2;
SSL_DEBUG_MSG( 2, ( "=> derive keys" ) );
/*
* 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( ssl->resume == 0 )
{
size_t len = ssl->pmslen;
SSL_DEBUG_BUF( 3, "premaster secret", ssl->premaster, len );
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
for( i = 0; i < 3; i++ )
{
memset( padding, 'A' + i, 1 + i );
sha1_starts( &sha1 );
sha1_update( &sha1, padding, 1 + i );
sha1_update( &sha1, ssl->premaster, len );
sha1_update( &sha1, ssl->randbytes, 64 );
sha1_finish( &sha1, sha1sum );
md5_starts( &md5 );
md5_update( &md5, ssl->premaster, len );
md5_update( &md5, sha1sum, 20 );
md5_finish( &md5, ssl->session->master + i * 16 );
}
}
else
tls1_prf( ssl->premaster, len, "master secret",
ssl->randbytes, 64, ssl->session->master, 48 );
memset( ssl->premaster, 0, sizeof( ssl->premaster ) );
}
else
SSL_DEBUG_MSG( 3, ( "no premaster (session resumed)" ) );
/*
* Swap the client and server random values.
*/
memcpy( tmp, ssl->randbytes, 64 );
memcpy( ssl->randbytes, tmp + 32, 32 );
memcpy( ssl->randbytes + 32, tmp, 32 );
memset( tmp, 0, 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 )
*/
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
for( i = 0; i < 16; i++ )
{
memset( padding, 'A' + i, 1 + i );
sha1_starts( &sha1 );
sha1_update( &sha1, padding, 1 + i );
sha1_update( &sha1, ssl->session->master, 48 );
sha1_update( &sha1, ssl->randbytes, 64 );
sha1_finish( &sha1, sha1sum );
md5_starts( &md5 );
md5_update( &md5, ssl->session->master, 48 );
md5_update( &md5, sha1sum, 20 );
md5_finish( &md5, keyblk + i * 16 );
}
memset( &md5, 0, sizeof( md5 ) );
memset( &sha1, 0, sizeof( sha1 ) );
memset( padding, 0, sizeof( padding ) );
memset( sha1sum, 0, sizeof( sha1sum ) );
}
else
tls1_prf( ssl->session->master, 48, "key expansion",
ssl->randbytes, 64, keyblk, 256 );
SSL_DEBUG_MSG( 3, ( "ciphersuite = %s", ssl_get_ciphersuite( ssl ) ) );
SSL_DEBUG_BUF( 3, "master secret", ssl->session->master, 48 );
SSL_DEBUG_BUF( 4, "random bytes", ssl->randbytes, 64 );
SSL_DEBUG_BUF( 4, "key block", keyblk, 256 );
memset( ssl->randbytes, 0, sizeof( ssl->randbytes ) );
/*
* Determine the appropriate key, IV and MAC length.
*/
switch( ssl->session->ciphersuite )
{
#if defined(POLARSSL_ARC4_C)
case SSL_RSA_RC4_128_MD5:
ssl->keylen = 16; ssl->minlen = 16;
ssl->ivlen = 0; ssl->maclen = 16;
break;
case SSL_RSA_RC4_128_SHA:
ssl->keylen = 16; ssl->minlen = 20;
ssl->ivlen = 0; ssl->maclen = 20;
break;
#endif
#if defined(POLARSSL_DES_C)
case SSL_RSA_DES_168_SHA:
case SSL_EDH_RSA_DES_168_SHA:
ssl->keylen = 24; ssl->minlen = 24;
ssl->ivlen = 8; ssl->maclen = 20;
break;
#endif
#if defined(POLARSSL_AES_C)
case SSL_RSA_AES_128_SHA:
case SSL_EDH_RSA_AES_128_SHA:
ssl->keylen = 16; ssl->minlen = 32;
ssl->ivlen = 16; ssl->maclen = 20;
break;
case SSL_RSA_AES_256_SHA:
case SSL_EDH_RSA_AES_256_SHA:
ssl->keylen = 32; ssl->minlen = 32;
ssl->ivlen = 16; ssl->maclen = 20;
break;
#endif
#if defined(POLARSSL_CAMELLIA_C)
case SSL_RSA_CAMELLIA_128_SHA:
case SSL_EDH_RSA_CAMELLIA_128_SHA:
ssl->keylen = 16; ssl->minlen = 32;
ssl->ivlen = 16; ssl->maclen = 20;
break;
case SSL_RSA_CAMELLIA_256_SHA:
case SSL_EDH_RSA_CAMELLIA_256_SHA:
ssl->keylen = 32; ssl->minlen = 32;
ssl->ivlen = 16; ssl->maclen = 20;
break;
#endif
default:
SSL_DEBUG_MSG( 1, ( "ciphersuite %s is not available",
ssl_get_ciphersuite( ssl ) ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
SSL_DEBUG_MSG( 3, ( "keylen: %d, minlen: %d, ivlen: %d, maclen: %d",
ssl->keylen, ssl->minlen, ssl->ivlen, ssl->maclen ) );
/*
* Finally setup the cipher contexts, IVs and MAC secrets.
*/
if( ssl->endpoint == SSL_IS_CLIENT )
{
key1 = keyblk + ssl->maclen * 2;
key2 = keyblk + ssl->maclen * 2 + ssl->keylen;
memcpy( ssl->mac_enc, keyblk, ssl->maclen );
memcpy( ssl->mac_dec, keyblk + ssl->maclen, ssl->maclen );
/*
* This is not used in TLS v1.1.
*/
memcpy( ssl->iv_enc, key2 + ssl->keylen, ssl->ivlen );
memcpy( ssl->iv_dec, key2 + ssl->keylen + ssl->ivlen,
ssl->ivlen );
}
else
{
key1 = keyblk + ssl->maclen * 2 + ssl->keylen;
key2 = keyblk + ssl->maclen * 2;
memcpy( ssl->mac_dec, keyblk, ssl->maclen );
memcpy( ssl->mac_enc, keyblk + ssl->maclen, ssl->maclen );
/*
* This is not used in TLS v1.1.
*/
memcpy( ssl->iv_dec, key1 + ssl->keylen, ssl->ivlen );
memcpy( ssl->iv_enc, key1 + ssl->keylen + ssl->ivlen,
ssl->ivlen );
}
switch( ssl->session->ciphersuite )
{
#if defined(POLARSSL_ARC4_C)
case SSL_RSA_RC4_128_MD5:
case SSL_RSA_RC4_128_SHA:
arc4_setup( (arc4_context *) ssl->ctx_enc, key1, ssl->keylen );
arc4_setup( (arc4_context *) ssl->ctx_dec, key2, ssl->keylen );
break;
#endif
#if defined(POLARSSL_DES_C)
case SSL_RSA_DES_168_SHA:
case SSL_EDH_RSA_DES_168_SHA:
des3_set3key_enc( (des3_context *) ssl->ctx_enc, key1 );
des3_set3key_dec( (des3_context *) ssl->ctx_dec, key2 );
break;
#endif
#if defined(POLARSSL_AES_C)
case SSL_RSA_AES_128_SHA:
case SSL_EDH_RSA_AES_128_SHA:
aes_setkey_enc( (aes_context *) ssl->ctx_enc, key1, 128 );
aes_setkey_dec( (aes_context *) ssl->ctx_dec, key2, 128 );
break;
case SSL_RSA_AES_256_SHA:
case SSL_EDH_RSA_AES_256_SHA:
aes_setkey_enc( (aes_context *) ssl->ctx_enc, key1, 256 );
aes_setkey_dec( (aes_context *) ssl->ctx_dec, key2, 256 );
break;
#endif
#if defined(POLARSSL_CAMELLIA_C)
case SSL_RSA_CAMELLIA_128_SHA:
case SSL_EDH_RSA_CAMELLIA_128_SHA:
camellia_setkey_enc( (camellia_context *) ssl->ctx_enc, key1, 128 );
camellia_setkey_dec( (camellia_context *) ssl->ctx_dec, key2, 128 );
break;
case SSL_RSA_CAMELLIA_256_SHA:
case SSL_EDH_RSA_CAMELLIA_256_SHA:
camellia_setkey_enc( (camellia_context *) ssl->ctx_enc, key1, 256 );
camellia_setkey_dec( (camellia_context *) ssl->ctx_dec, key2, 256 );
break;
#endif
default:
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
memset( keyblk, 0, sizeof( keyblk ) );
SSL_DEBUG_MSG( 2, ( "<= derive keys" ) );
return( 0 );
}
void ssl_calc_verify( ssl_context *ssl, unsigned char hash[36] )
{
md5_context md5;
sha1_context sha1;
unsigned char pad_1[48];
unsigned char pad_2[48];
SSL_DEBUG_MSG( 2, ( "=> calc verify" ) );
memcpy( &md5 , &ssl->fin_md5 , sizeof( md5_context ) );
memcpy( &sha1, &ssl->fin_sha1, sizeof( sha1_context ) );
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
memset( pad_1, 0x36, 48 );
memset( pad_2, 0x5C, 48 );
md5_update( &md5, ssl->session->master, 48 );
md5_update( &md5, pad_1, 48 );
md5_finish( &md5, hash );
md5_starts( &md5 );
md5_update( &md5, ssl->session->master, 48 );
md5_update( &md5, pad_2, 48 );
md5_update( &md5, hash, 16 );
md5_finish( &md5, hash );
sha1_update( &sha1, ssl->session->master, 48 );
sha1_update( &sha1, pad_1, 40 );
sha1_finish( &sha1, hash + 16 );
sha1_starts( &sha1 );
sha1_update( &sha1, ssl->session->master, 48 );
sha1_update( &sha1, pad_2, 40 );
sha1_update( &sha1, hash + 16, 20 );
sha1_finish( &sha1, hash + 16 );
}
else /* TLSv1 */
{
md5_finish( &md5, hash );
sha1_finish( &sha1, hash + 16 );
}
SSL_DEBUG_BUF( 3, "calculated verify result", hash, 36 );
SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
return;
}
/*
* SSLv3.0 MAC functions
*/
static void ssl_mac_md5( unsigned char *secret,
unsigned char *buf, size_t len,
unsigned char *ctr, int type )
{
unsigned char header[11];
unsigned char padding[48];
md5_context md5;
memcpy( header, ctr, 8 );
header[ 8] = (unsigned char) type;
header[ 9] = (unsigned char)( len >> 8 );
header[10] = (unsigned char)( len );
memset( padding, 0x36, 48 );
md5_starts( &md5 );
md5_update( &md5, secret, 16 );
md5_update( &md5, padding, 48 );
md5_update( &md5, header, 11 );
md5_update( &md5, buf, len );
md5_finish( &md5, buf + len );
memset( padding, 0x5C, 48 );
md5_starts( &md5 );
md5_update( &md5, secret, 16 );
md5_update( &md5, padding, 48 );
md5_update( &md5, buf + len, 16 );
md5_finish( &md5, buf + len );
}
static void ssl_mac_sha1( unsigned char *secret,
unsigned char *buf, size_t len,
unsigned char *ctr, int type )
{
unsigned char header[11];
unsigned char padding[40];
sha1_context sha1;
memcpy( header, ctr, 8 );
header[ 8] = (unsigned char) type;
header[ 9] = (unsigned char)( len >> 8 );
header[10] = (unsigned char)( len );
memset( padding, 0x36, 40 );
sha1_starts( &sha1 );
sha1_update( &sha1, secret, 20 );
sha1_update( &sha1, padding, 40 );
sha1_update( &sha1, header, 11 );
sha1_update( &sha1, buf, len );
sha1_finish( &sha1, buf + len );
memset( padding, 0x5C, 40 );
sha1_starts( &sha1 );
sha1_update( &sha1, secret, 20 );
sha1_update( &sha1, padding, 40 );
sha1_update( &sha1, buf + len, 20 );
sha1_finish( &sha1, buf + len );
}
/*
* Encryption/decryption functions
*/
static int ssl_encrypt_buf( ssl_context *ssl )
{
size_t i, padlen;
SSL_DEBUG_MSG( 2, ( "=> encrypt buf" ) );
/*
* Add MAC then encrypt
*/
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( ssl->maclen == 16 )
ssl_mac_md5( ssl->mac_enc,
ssl->out_msg, ssl->out_msglen,
ssl->out_ctr, ssl->out_msgtype );
if( ssl->maclen == 20 )
ssl_mac_sha1( ssl->mac_enc,
ssl->out_msg, ssl->out_msglen,
ssl->out_ctr, ssl->out_msgtype );
}
else
{
if( ssl->maclen == 16 )
md5_hmac( ssl->mac_enc, 16,
ssl->out_ctr, ssl->out_msglen + 13,
ssl->out_msg + ssl->out_msglen );
if( ssl->maclen == 20 )
sha1_hmac( ssl->mac_enc, 20,
ssl->out_ctr, ssl->out_msglen + 13,
ssl->out_msg + ssl->out_msglen );
}
SSL_DEBUG_BUF( 4, "computed mac",
ssl->out_msg + ssl->out_msglen, ssl->maclen );
ssl->out_msglen += ssl->maclen;
for( i = 8; i > 0; i-- )
if( ++ssl->out_ctr[i - 1] != 0 )
break;
if( ssl->ivlen == 0 )
{
#if defined(POLARSSL_ARC4_C)
padlen = 0;
SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of padding",
ssl->out_msglen, 0 ) );
SSL_DEBUG_BUF( 4, "before encrypt: output payload",
ssl->out_msg, ssl->out_msglen );
arc4_crypt( (arc4_context *) ssl->ctx_enc,
ssl->out_msglen, ssl->out_msg,
ssl->out_msg );
#else
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
}
else
{
unsigned char *enc_msg;
size_t enc_msglen;
padlen = ssl->ivlen - ( ssl->out_msglen + 1 ) % ssl->ivlen;
if( padlen == ssl->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;
/*
* Prepend per-record IV for block cipher in TLS v1.1 as per
* Method 1 (6.2.3.2. in RFC4346)
*/
if( ssl->minor_ver == SSL_MINOR_VERSION_2 )
{
/*
* Generate IV
*/
int ret = ssl->f_rng( ssl->p_rng, ssl->iv_enc, ssl->ivlen );
if( ret != 0 )
return( ret );
/*
* Shift message for ivlen bytes and prepend IV
*/
memmove( ssl->out_msg + ssl->ivlen, ssl->out_msg, ssl->out_msglen );
memcpy( ssl->out_msg, ssl->iv_enc, ssl->ivlen );
/*
* Fix pointer positions and message length with added IV
*/
enc_msg = ssl->out_msg + ssl->ivlen;
enc_msglen = ssl->out_msglen;
ssl->out_msglen += ssl->ivlen;
}
SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of IV and %d bytes of padding",
ssl->out_msglen, ssl->ivlen, padlen + 1 ) );
SSL_DEBUG_BUF( 4, "before encrypt: output payload",
ssl->out_msg, ssl->out_msglen );
switch( ssl->ivlen )
{
case 8:
#if defined(POLARSSL_DES_C)
des3_crypt_cbc( (des3_context *) ssl->ctx_enc,
DES_ENCRYPT, enc_msglen,
ssl->iv_enc, enc_msg, enc_msg );
break;
#endif
case 16:
#if defined(POLARSSL_AES_C)
if ( ssl->session->ciphersuite == SSL_RSA_AES_128_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_AES_128_SHA ||
ssl->session->ciphersuite == SSL_RSA_AES_256_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_AES_256_SHA)
{
aes_crypt_cbc( (aes_context *) ssl->ctx_enc,
AES_ENCRYPT, enc_msglen,
ssl->iv_enc, enc_msg, enc_msg);
break;
}
#endif
#if defined(POLARSSL_CAMELLIA_C)
if ( ssl->session->ciphersuite == SSL_RSA_CAMELLIA_128_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_CAMELLIA_128_SHA ||
ssl->session->ciphersuite == SSL_RSA_CAMELLIA_256_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_CAMELLIA_256_SHA)
{
camellia_crypt_cbc( (camellia_context *) ssl->ctx_enc,
CAMELLIA_ENCRYPT, enc_msglen,
ssl->iv_enc, enc_msg, enc_msg );
break;
}
#endif
default:
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
}
SSL_DEBUG_MSG( 2, ( "<= encrypt buf" ) );
return( 0 );
}
static int ssl_decrypt_buf( ssl_context *ssl )
{
size_t i, padlen = 0, correct = 1;
unsigned char tmp[20];
SSL_DEBUG_MSG( 2, ( "=> decrypt buf" ) );
if( ssl->in_msglen < ssl->minlen )
{
SSL_DEBUG_MSG( 1, ( "in_msglen (%d) < minlen (%d)",
ssl->in_msglen, ssl->minlen ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
if( ssl->ivlen == 0 )
{
#if defined(POLARSSL_ARC4_C)
padlen = 0;
arc4_crypt( (arc4_context *) ssl->ctx_dec,
ssl->in_msglen, ssl->in_msg,
ssl->in_msg );
#else
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
}
else
{
/*
* Decrypt and check the padding
*/
unsigned char *dec_msg;
unsigned char *dec_msg_result;
size_t dec_msglen;
size_t minlen = 0;
/*
* Check immediate ciphertext sanity
*/
if( ssl->in_msglen % ssl->ivlen != 0 )
{
SSL_DEBUG_MSG( 1, ( "msglen (%d) %% ivlen (%d) != 0",
ssl->in_msglen, ssl->ivlen ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
if( ssl->minor_ver >= SSL_MINOR_VERSION_2 )
minlen += ssl->ivlen;
if( ssl->in_msglen < minlen + ssl->ivlen ||
ssl->in_msglen < minlen + ssl->maclen + 1 )
{
SSL_DEBUG_MSG( 1, ( "msglen (%d) < max( ivlen(%d), maclen (%d) + 1 ) ( + expl IV )",
ssl->in_msglen, ssl->ivlen, ssl->maclen ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
dec_msglen = ssl->in_msglen;
dec_msg = ssl->in_msg;
dec_msg_result = ssl->in_msg;
/*
* Initialize for prepended IV for block cipher in TLS v1.1
*/
if( ssl->minor_ver == SSL_MINOR_VERSION_2 )
{
dec_msg += ssl->ivlen;
dec_msglen -= ssl->ivlen;
ssl->in_msglen -= ssl->ivlen;
for( i = 0; i < ssl->ivlen; i++ )
ssl->iv_dec[i] = ssl->in_msg[i];
}
switch( ssl->ivlen )
{
#if defined(POLARSSL_DES_C)
case 8:
des3_crypt_cbc( (des3_context *) ssl->ctx_dec,
DES_DECRYPT, dec_msglen,
ssl->iv_dec, dec_msg, dec_msg_result );
break;
#endif
case 16:
#if defined(POLARSSL_AES_C)
if ( ssl->session->ciphersuite == SSL_RSA_AES_128_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_AES_128_SHA ||
ssl->session->ciphersuite == SSL_RSA_AES_256_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_AES_256_SHA)
{
aes_crypt_cbc( (aes_context *) ssl->ctx_dec,
AES_DECRYPT, dec_msglen,
ssl->iv_dec, dec_msg, dec_msg_result );
break;
}
#endif
#if defined(POLARSSL_CAMELLIA_C)
if ( ssl->session->ciphersuite == SSL_RSA_CAMELLIA_128_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_CAMELLIA_128_SHA ||
ssl->session->ciphersuite == SSL_RSA_CAMELLIA_256_SHA ||
ssl->session->ciphersuite == SSL_EDH_RSA_CAMELLIA_256_SHA)
{
camellia_crypt_cbc( (camellia_context *) ssl->ctx_dec,
CAMELLIA_DECRYPT, dec_msglen,
ssl->iv_dec, dec_msg, dec_msg_result );
break;
}
#endif
default:
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
padlen = 1 + ssl->in_msg[ssl->in_msglen - 1];
if( ssl->in_msglen < ssl->maclen + padlen )
{
#if defined(POLARSSL_SSL_DEBUG_ALL)
SSL_DEBUG_MSG( 1, ( "msglen (%d) < maclen (%d) + padlen (%d)",
ssl->in_msglen, ssl->maclen, padlen ) );
#endif
padlen = 0;
correct = 0;
}
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( padlen > ssl->ivlen )
{
#if defined(POLARSSL_SSL_DEBUG_ALL)
SSL_DEBUG_MSG( 1, ( "bad padding length: is %d, "
"should be no more than %d",
padlen, ssl->ivlen ) );
#endif
correct = 0;
}
}
else
{
/*
* TLSv1+: always check the padding up to the first failure
* and fake check up to 256 bytes of padding
*/
size_t pad_count = 0, fake_pad_count = 0;
size_t padding_idx = ssl->in_msglen - padlen - 1;
for( i = 1; i <= padlen; i++ )
pad_count += ( ssl->in_msg[padding_idx + i] == padlen - 1 );
for( ; i <= 256; i++ )
fake_pad_count += ( ssl->in_msg[padding_idx + i] == padlen - 1 );
correct &= ( pad_count == padlen ); /* Only 1 on correct padding */
correct &= ( pad_count + fake_pad_count < 512 ); /* Always 1 */
#if defined(POLARSSL_SSL_DEBUG_ALL)
if( padlen > 0 && correct == 0)
SSL_DEBUG_MSG( 1, ( "bad padding byte detected" ) );
#endif
padlen &= correct * 0x1FF;
}
}
SSL_DEBUG_BUF( 4, "raw buffer after decryption",
ssl->in_msg, ssl->in_msglen );
/*
* Always compute the MAC (RFC4346, CBCTIME).
*/
ssl->in_msglen -= ( ssl->maclen + padlen );
ssl->in_hdr[3] = (unsigned char)( ssl->in_msglen >> 8 );
ssl->in_hdr[4] = (unsigned char)( ssl->in_msglen );
memcpy( tmp, ssl->in_msg + ssl->in_msglen, 20 );
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( ssl->maclen == 16 )
ssl_mac_md5( ssl->mac_dec,
ssl->in_msg, ssl->in_msglen,
ssl->in_ctr, ssl->in_msgtype );
else
ssl_mac_sha1( ssl->mac_dec,
ssl->in_msg, ssl->in_msglen,
ssl->in_ctr, ssl->in_msgtype );
}
else
{
/*
* Process MAC and always update for padlen afterwards to make
* total time independent of padlen
*
* extra_run compensates MAC check for padlen
*
* Known timing attacks:
* - Lucky Thirteen (http://www.isg.rhul.ac.uk/tls/TLStiming.pdf)
*
* We use ( ( Lx + 8 ) / 64 ) to handle 'negative Lx' values
* correctly. (We round down instead of up, so -56 is the correct
* value for our calculations instead of -55)
*/
int j, extra_run = 0;
extra_run = ( 13 + ssl->in_msglen + padlen + 8 ) / 64 -
( 13 + ssl->in_msglen + 8 ) / 64;
extra_run &= correct * 0xFF;
if( ssl->maclen == 16 )
{
md5_context ctx;
md5_hmac_starts( &ctx, ssl->mac_dec, 16 );
md5_hmac_update( &ctx, ssl->in_ctr, ssl->in_msglen + 13 );
md5_hmac_finish( &ctx, ssl->in_msg + ssl->in_msglen );
for( j = 0; j < extra_run; j++ )
md5_process( &ctx, ssl->in_msg );
}
else if( ssl->maclen == 20 )
{
sha1_context ctx;
sha1_hmac_starts( &ctx, ssl->mac_dec, 20 );
sha1_hmac_update( &ctx, ssl->in_ctr, ssl->in_msglen + 13 );
sha1_hmac_finish( &ctx, ssl->in_msg + ssl->in_msglen );
for( j = 0; j < extra_run; j++ )
sha1_process( &ctx, ssl->in_msg );
}
else if( ssl->maclen != 0 )
{
SSL_DEBUG_MSG( 1, ( "invalid MAC len: %d",
ssl->maclen ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
}
SSL_DEBUG_BUF( 4, "message mac", tmp, ssl->maclen );
SSL_DEBUG_BUF( 4, "computed mac", ssl->in_msg + ssl->in_msglen,
ssl->maclen );
if( memcmp( tmp, ssl->in_msg + ssl->in_msglen,
ssl->maclen ) != 0 )
{
#if defined(POLARSSL_SSL_DEBUG_ALL)
SSL_DEBUG_MSG( 1, ( "message mac does not match" ) );
#endif
correct = 0;
}
/*
* Finally check the correct flag
*/
if( correct == 0 )
return( POLARSSL_ERR_SSL_INVALID_MAC );
if( ssl->in_msglen == 0 )
{
ssl->nb_zero++;
/*
* Three or more empty messages may be a DoS attack
* (excessive CPU consumption).
*/
if( ssl->nb_zero > 3 )
{
SSL_DEBUG_MSG( 1, ( "received four consecutive empty "
"messages, possible DoS attack" ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
}
else
ssl->nb_zero = 0;
for( i = 8; i > 0; i-- )
if( ++ssl->in_ctr[i - 1] != 0 )
break;
SSL_DEBUG_MSG( 2, ( "<= decrypt buf" ) );
return( 0 );
}
/*
* Fill the input message buffer
*/
int ssl_fetch_input( ssl_context *ssl, size_t nb_want )
{
int ret;
size_t len;
SSL_DEBUG_MSG( 2, ( "=> fetch input" ) );
while( ssl->in_left < nb_want )
{
len = nb_want - ssl->in_left;
ret = ssl->f_recv( ssl->p_recv, ssl->in_hdr + ssl->in_left, len );
SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
SSL_DEBUG_RET( 2, "ssl->f_recv", ret );
if( ret == 0 )
return( POLARSSL_ERR_SSL_CONN_EOF );
if( ret < 0 )
return( ret );
ssl->in_left += ret;
}
SSL_DEBUG_MSG( 2, ( "<= fetch input" ) );
return( 0 );
}
/*
* Flush any data not yet written
*/
int ssl_flush_output( ssl_context *ssl )
{
int ret;
unsigned char *buf;
SSL_DEBUG_MSG( 2, ( "=> flush output" ) );
while( ssl->out_left > 0 )
{
SSL_DEBUG_MSG( 2, ( "message length: %d, out_left: %d",
5 + ssl->out_msglen, ssl->out_left ) );
buf = ssl->out_hdr + 5 + ssl->out_msglen - ssl->out_left;
ret = ssl->f_send( ssl->p_send, buf, ssl->out_left );
SSL_DEBUG_RET( 2, "ssl->f_send", ret );
if( ret <= 0 )
return( ret );
ssl->out_left -= ret;
}
SSL_DEBUG_MSG( 2, ( "<= flush output" ) );
return( 0 );
}
/*
* Record layer functions
*/
int ssl_write_record( ssl_context *ssl )
{
int ret;
size_t len = ssl->out_msglen;
SSL_DEBUG_MSG( 2, ( "=> write record" ) );
ssl->out_hdr[0] = (unsigned char) ssl->out_msgtype;
ssl->out_hdr[1] = (unsigned char) ssl->major_ver;
ssl->out_hdr[2] = (unsigned char) ssl->minor_ver;
ssl->out_hdr[3] = (unsigned char)( len >> 8 );
ssl->out_hdr[4] = (unsigned char)( len );
if( ssl->out_msgtype == SSL_MSG_HANDSHAKE )
{
ssl->out_msg[1] = (unsigned char)( ( len - 4 ) >> 16 );
ssl->out_msg[2] = (unsigned char)( ( len - 4 ) >> 8 );
ssl->out_msg[3] = (unsigned char)( ( len - 4 ) );
md5_update( &ssl->fin_md5 , ssl->out_msg, len );
sha1_update( &ssl->fin_sha1, ssl->out_msg, len );
}
if( ssl->do_crypt != 0 )
{
if( ( ret = ssl_encrypt_buf( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_encrypt_buf", ret );
return( ret );
}
len = ssl->out_msglen;
ssl->out_hdr[3] = (unsigned char)( len >> 8 );
ssl->out_hdr[4] = (unsigned char)( len );
}
ssl->out_left = 5 + ssl->out_msglen;
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],
( ssl->out_hdr[3] << 8 ) | ssl->out_hdr[4] ) );
SSL_DEBUG_BUF( 4, "output record sent to network",
ssl->out_hdr, 5 + ssl->out_msglen );
if( ( ret = ssl_flush_output( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_flush_output", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write record" ) );
return( 0 );
}
int ssl_read_record( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> read record" ) );
if( ssl->in_hslen != 0 &&
ssl->in_hslen < ssl->in_msglen )
{
/*
* Get next Handshake message in the current record
*/
ssl->in_msglen -= ssl->in_hslen;
memmove( ssl->in_msg, ssl->in_msg + ssl->in_hslen,
ssl->in_msglen );
ssl->in_hslen = 4;
ssl->in_hslen += ( ssl->in_msg[2] << 8 ) | ssl->in_msg[3];
SSL_DEBUG_MSG( 3, ( "handshake message: msglen ="
" %d, type = %d, hslen = %d",
ssl->in_msglen, ssl->in_msg[0], ssl->in_hslen ) );
if( ssl->in_msglen < 4 || ssl->in_msg[1] != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad handshake length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( ssl->in_msglen < ssl->in_hslen )
{
SSL_DEBUG_MSG( 1, ( "bad handshake length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
md5_update( &ssl->fin_md5 , ssl->in_msg, ssl->in_hslen );
sha1_update( &ssl->fin_sha1, ssl->in_msg, ssl->in_hslen );
return( 0 );
}
ssl->in_hslen = 0;
/*
* Read the record header and validate it
*/
if( ( ret = ssl_fetch_input( ssl, 5 ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
ssl->in_msgtype = ssl->in_hdr[0];
ssl->in_msglen = ( ssl->in_hdr[3] << 8 ) | ssl->in_hdr[4];
SSL_DEBUG_MSG( 3, ( "input record: msgtype = %d, "
"version = [%d:%d], msglen = %d",
ssl->in_hdr[0], ssl->in_hdr[1], ssl->in_hdr[2],
( ssl->in_hdr[3] << 8 ) | ssl->in_hdr[4] ) );
if( ssl->in_hdr[1] != ssl->major_ver )
{
SSL_DEBUG_MSG( 1, ( "major version mismatch" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( ssl->in_hdr[2] > ssl->max_minor_ver )
{
SSL_DEBUG_MSG( 1, ( "minor version mismatch" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/*
* Make sure the message length is acceptable
*/
if( ssl->do_crypt == 0 )
{
if( ssl->in_msglen < 1 ||
ssl->in_msglen > SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
}
else
{
if( ssl->in_msglen < ssl->minlen )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( ssl->minor_ver == SSL_MINOR_VERSION_0 &&
ssl->in_msglen > ssl->minlen + SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/*
* TLS encrypted messages can have up to 256 bytes of padding
*/
if( ssl->minor_ver == SSL_MINOR_VERSION_1 &&
ssl->in_msglen > ssl->minlen + SSL_MAX_CONTENT_LEN + 256 )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
}
/*
* Read and optionally decrypt the message contents
*/
if( ( ret = ssl_fetch_input( ssl, 5 + ssl->in_msglen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
SSL_DEBUG_BUF( 4, "input record from network",
ssl->in_hdr, 5 + ssl->in_msglen );
if( ssl->do_crypt != 0 )
{
if( ( ret = ssl_decrypt_buf( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_decrypt_buf", ret );
return( ret );
}
SSL_DEBUG_BUF( 4, "input payload after decrypt",
ssl->in_msg, ssl->in_msglen );
if( ssl->in_msglen > SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
}
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE )
{
ssl->in_hslen = 4;
ssl->in_hslen += ( ssl->in_msg[2] << 8 ) | ssl->in_msg[3];
SSL_DEBUG_MSG( 3, ( "handshake message: msglen ="
" %d, type = %d, hslen = %d",
ssl->in_msglen, ssl->in_msg[0], ssl->in_hslen ) );
/*
* Additional checks to validate the handshake header
*/
if( ssl->in_msglen < 4 || ssl->in_msg[1] != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad handshake length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( ssl->in_msglen < ssl->in_hslen )
{
SSL_DEBUG_MSG( 1, ( "bad handshake length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
md5_update( &ssl->fin_md5 , ssl->in_msg, ssl->in_hslen );
sha1_update( &ssl->fin_sha1, ssl->in_msg, ssl->in_hslen );
}
if( ssl->in_msgtype == SSL_MSG_ALERT )
{
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
*/
if( ssl->in_msg[0] == SSL_ALERT_LEVEL_FATAL )
{
SSL_DEBUG_MSG( 1, ( "is a fatal alert message" ) );
/**
* Subtract from error code as ssl->in_msg[1] is 7-bit positive
* error identifier.
*/
return( POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE - ssl->in_msg[1] );
}
if( ssl->in_msg[0] == SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == SSL_ALERT_MSG_CLOSE_NOTIFY )
{
SSL_DEBUG_MSG( 2, ( "is a close notify message" ) );
return( POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY );
}
}
ssl->in_left = 0;
SSL_DEBUG_MSG( 2, ( "<= read record" ) );
return( 0 );
}
/*
* Handshake functions
*/
int ssl_write_certificate( ssl_context *ssl )
{
int ret;
size_t i, n;
const x509_cert *crt;
SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( ssl->endpoint == SSL_IS_CLIENT )
{
if( ssl->client_auth == 0 )
{
SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
/*
* If using SSLv3 and got no cert, send an Alert message
* (otherwise an empty Certificate message will be sent).
*/
if( ssl->own_cert == NULL &&
ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
ssl->out_msglen = 2;
ssl->out_msgtype = SSL_MSG_ALERT;
ssl->out_msg[0] = SSL_ALERT_LEVEL_WARNING;
ssl->out_msg[1] = SSL_ALERT_MSG_NO_CERT;
SSL_DEBUG_MSG( 2, ( "got no certificate to send" ) );
goto write_msg;
}
}
else /* SSL_IS_SERVER */
{
if( ssl->own_cert == NULL )
{
SSL_DEBUG_MSG( 1, ( "got no certificate to send" ) );
return( POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED );
}
}
SSL_DEBUG_CRT( 3, "own certificate", ssl->own_cert );
/*
* 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 = ssl->own_cert;
while( crt != NULL )
{
n = crt->raw.len;
if( i + 3 + n > SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "certificate too large, %d > %d",
i + 3 + n, SSL_MAX_CONTENT_LEN ) );
return( POLARSSL_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 = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_CERTIFICATE;
write_msg:
ssl->state++;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write certificate" ) );
return( 0 );
}
int ssl_parse_certificate( ssl_context *ssl )
{
int ret;
size_t i, n;
SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( ssl->endpoint == SSL_IS_SERVER &&
ssl->authmode == SSL_VERIFY_NONE )
{
ssl->verify_result = BADCERT_SKIP_VERIFY;
SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
ssl->state++;
/*
* Check if the client sent an empty certificate
*/
if( ssl->endpoint == SSL_IS_SERVER &&
ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( ssl->in_msglen == 2 &&
ssl->in_msgtype == SSL_MSG_ALERT &&
ssl->in_msg[0] == SSL_ALERT_LEVEL_WARNING &&
ssl->in_msg[1] == SSL_ALERT_MSG_NO_CERT )
{
SSL_DEBUG_MSG( 1, ( "SSLv3 client has no certificate" ) );
ssl->verify_result = BADCERT_MISSING;
if( ssl->authmode == SSL_VERIFY_OPTIONAL )
return( 0 );
else
return( POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE );
}
}
if( ssl->endpoint == SSL_IS_SERVER &&
ssl->minor_ver != SSL_MINOR_VERSION_0 )
{
if( ssl->in_hslen == 7 &&
ssl->in_msgtype == SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == SSL_HS_CERTIFICATE &&
memcmp( ssl->in_msg + 4, "\0\0\0", 3 ) == 0 )
{
SSL_DEBUG_MSG( 1, ( "TLSv1 client has no certificate" ) );
ssl->verify_result = BADCERT_MISSING;
if( ssl->authmode == SSL_VERIFY_REQUIRED )
return( POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE );
else
return( 0 );
}
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ssl->in_msg[0] != SSL_HS_CERTIFICATE || ssl->in_hslen < 10 )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
/*
* Same message structure as in ssl_write_certificate()
*/
n = ( ssl->in_msg[5] << 8 ) | ssl->in_msg[6];
if( ssl->in_msg[4] != 0 || ssl->in_hslen != 7 + n )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
if( ( ssl->peer_cert = (x509_cert *) malloc(
sizeof( x509_cert ) ) ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed",
sizeof( x509_cert ) ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
memset( ssl->peer_cert, 0, sizeof( x509_cert ) );
i = 7;
while( i < ssl->in_hslen )
{
if( ssl->in_msg[i] != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_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 )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
ret = x509parse_crt( ssl->peer_cert, ssl->in_msg + i, n );
if( ret != 0 )
{
SSL_DEBUG_RET( 1, " x509parse_crt", ret );
return( ret );
}
i += n;
}
SSL_DEBUG_CRT( 3, "peer certificate", ssl->peer_cert );
if( ssl->authmode != SSL_VERIFY_NONE )
{
if( ssl->ca_chain == NULL )
{
SSL_DEBUG_MSG( 1, ( "got no CA chain" ) );
return( POLARSSL_ERR_SSL_CA_CHAIN_REQUIRED );
}
ret = x509parse_verify( ssl->peer_cert, ssl->ca_chain, ssl->ca_crl,
ssl->peer_cn, &ssl->verify_result,
ssl->f_vrfy, ssl->p_vrfy );
if( ret != 0 )
SSL_DEBUG_RET( 1, "x509_verify_cert", ret );
if( ssl->authmode != SSL_VERIFY_REQUIRED )
ret = 0;
}
SSL_DEBUG_MSG( 2, ( "<= parse certificate" ) );
return( ret );
}
int ssl_write_change_cipher_spec( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> write change cipher spec" ) );
ssl->out_msgtype = SSL_MSG_CHANGE_CIPHER_SPEC;
ssl->out_msglen = 1;
ssl->out_msg[0] = 1;
ssl->do_crypt = 0;
ssl->state++;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write change cipher spec" ) );
return( 0 );
}
int ssl_parse_change_cipher_spec( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> parse change cipher spec" ) );
ssl->do_crypt = 0;
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_CHANGE_CIPHER_SPEC )
{
SSL_DEBUG_MSG( 1, ( "bad change cipher spec message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ssl->in_msglen != 1 || ssl->in_msg[0] != 1 )
{
SSL_DEBUG_MSG( 1, ( "bad change cipher spec message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC );
}
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse change cipher spec" ) );
return( 0 );
}
static void ssl_calc_finished(
ssl_context *ssl, unsigned char *buf, int from,
md5_context *md5, sha1_context *sha1 )
{
int len = 12;
char *sender;
unsigned char padbuf[48];
unsigned char md5sum[16];
unsigned char sha1sum[20];
SSL_DEBUG_MSG( 2, ( "=> calc finished" ) );
/*
* SSLv3:
* hash =
* MD5( master + pad2 +
* MD5( handshake + sender + master + pad1 ) )
* + SHA1( master + pad2 +
* SHA1( handshake + sender + master + pad1 ) )
*
* TLSv1:
* hash = PRF( master, finished_label,
* MD5( handshake ) + SHA1( handshake ) )[0..11]
*/
SSL_DEBUG_BUF( 4, "finished md5 state", (unsigned char *)
md5->state, sizeof( md5->state ) );
SSL_DEBUG_BUF( 4, "finished sha1 state", (unsigned char *)
sha1->state, sizeof( sha1->state ) );
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
sender = ( from == SSL_IS_CLIENT ) ? (char *) "CLNT"
: (char *) "SRVR";
memset( padbuf, 0x36, 48 );
md5_update( md5, (unsigned char *) sender, 4 );
md5_update( md5, ssl->session->master, 48 );
md5_update( md5, padbuf, 48 );
md5_finish( md5, md5sum );
sha1_update( sha1, (unsigned char *) sender, 4 );
sha1_update( sha1, ssl->session->master, 48 );
sha1_update( sha1, padbuf, 40 );
sha1_finish( sha1, sha1sum );
memset( padbuf, 0x5C, 48 );
md5_starts( md5 );
md5_update( md5, ssl->session->master, 48 );
md5_update( md5, padbuf, 48 );
md5_update( md5, md5sum, 16 );
md5_finish( md5, buf );
sha1_starts( sha1 );
sha1_update( sha1, ssl->session->master, 48 );
sha1_update( sha1, padbuf , 40 );
sha1_update( sha1, sha1sum, 20 );
sha1_finish( sha1, buf + 16 );
len += 24;
}
else
{
sender = ( from == SSL_IS_CLIENT )
? (char *) "client finished"
: (char *) "server finished";
md5_finish( md5, padbuf );
sha1_finish( sha1, padbuf + 16 );
tls1_prf( ssl->session->master, 48, sender,
padbuf, 36, buf, len );
}
SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
memset( md5, 0, sizeof( md5_context ) );
memset( sha1, 0, sizeof( sha1_context ) );
memset( padbuf, 0, sizeof( padbuf ) );
memset( md5sum, 0, sizeof( md5sum ) );
memset( sha1sum, 0, sizeof( sha1sum ) );
SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
int ssl_write_finished( ssl_context *ssl )
{
int ret, hash_len;
md5_context md5;
sha1_context sha1;
SSL_DEBUG_MSG( 2, ( "=> write finished" ) );
memcpy( &md5 , &ssl->fin_md5 , sizeof( md5_context ) );
memcpy( &sha1, &ssl->fin_sha1, sizeof( sha1_context ) );
ssl_calc_finished( ssl, ssl->out_msg + 4,
ssl->endpoint, &md5, &sha1 );
hash_len = ( ssl->minor_ver == SSL_MINOR_VERSION_0 ) ? 36 : 12;
ssl->out_msglen = 4 + hash_len;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_FINISHED;
/*
* In case of session resuming, invert the client and server
* ChangeCipherSpec messages order.
*/
if( ssl->resume != 0 )
{
if( ssl->endpoint == SSL_IS_CLIENT )
ssl->state = SSL_HANDSHAKE_OVER;
else
ssl->state = SSL_CLIENT_CHANGE_CIPHER_SPEC;
}
else
ssl->state++;
ssl->do_crypt = 1;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write finished" ) );
return( 0 );
}
int ssl_parse_finished( ssl_context *ssl )
{
int ret;
unsigned int hash_len;
unsigned char buf[36];
md5_context md5;
sha1_context sha1;
SSL_DEBUG_MSG( 2, ( "=> parse finished" ) );
memcpy( &md5 , &ssl->fin_md5 , sizeof( md5_context ) );
memcpy( &sha1, &ssl->fin_sha1, sizeof( sha1_context ) );
ssl->do_crypt = 1;
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
hash_len = ( ssl->minor_ver == SSL_MINOR_VERSION_0 ) ? 36 : 12;
if( ssl->in_msg[0] != SSL_HS_FINISHED ||
ssl->in_hslen != 4 + hash_len )
{
SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_FINISHED );
}
ssl_calc_finished( ssl, buf, ssl->endpoint ^ 1, &md5, &sha1 );
if( memcmp( ssl->in_msg + 4, buf, hash_len ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_FINISHED );
}
if( ssl->resume != 0 )
{
if( ssl->endpoint == SSL_IS_CLIENT )
ssl->state = SSL_CLIENT_CHANGE_CIPHER_SPEC;
if( ssl->endpoint == SSL_IS_SERVER )
ssl->state = SSL_HANDSHAKE_OVER;
}
else
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse finished" ) );
return( 0 );
}
/*
* Initialize an SSL context
*/
int ssl_init( ssl_context *ssl )
{
int len = SSL_BUFFER_LEN;
memset( ssl, 0, sizeof( ssl_context ) );
ssl->in_ctr = (unsigned char *) malloc( len );
ssl->in_hdr = ssl->in_ctr + 8;
ssl->in_msg = ssl->in_ctr + 13;
if( ssl->in_ctr == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed", len ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
ssl->out_ctr = (unsigned char *) malloc( len );
ssl->out_hdr = ssl->out_ctr + 8;
ssl->out_msg = ssl->out_ctr + 13;
if( ssl->out_ctr == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed", len ) );
free( ssl-> in_ctr );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
memset( ssl-> in_ctr, 0, SSL_BUFFER_LEN );
memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
ssl->hostname = NULL;
ssl->hostname_len = 0;
md5_starts( &ssl->fin_md5 );
sha1_starts( &ssl->fin_sha1 );
return( 0 );
}
/*
* Reset an initialized and used SSL context for re-use while retaining
* all application-set variables, function pointers and data.
*/
void ssl_session_reset( ssl_context *ssl )
{
ssl->state = SSL_HELLO_REQUEST;
ssl->in_offt = NULL;
ssl->in_msgtype = 0;
ssl->in_msglen = 0;
ssl->in_left = 0;
ssl->in_hslen = 0;
ssl->nb_zero = 0;
ssl->out_msgtype = 0;
ssl->out_msglen = 0;
ssl->out_left = 0;
ssl->do_crypt = 0;
ssl->pmslen = 0;
ssl->keylen = 0;
ssl->minlen = 0;
ssl->ivlen = 0;
ssl->maclen = 0;
memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
memset( ssl->in_ctr, 0, SSL_BUFFER_LEN );
memset( ssl->randbytes, 0, 64 );
memset( ssl->premaster, 0, 256 );
memset( ssl->iv_enc, 0, 16 );
memset( ssl->iv_dec, 0, 16 );
memset( ssl->mac_enc, 0, 32 );
memset( ssl->mac_dec, 0, 32 );
memset( ssl->ctx_enc, 0, 128 );
memset( ssl->ctx_dec, 0, 128 );
md5_starts( &ssl->fin_md5 );
sha1_starts( &ssl->fin_sha1 );
}
/*
* SSL set accessors
*/
void ssl_set_endpoint( ssl_context *ssl, int endpoint )
{
ssl->endpoint = endpoint;
}
void ssl_set_authmode( ssl_context *ssl, int authmode )
{
ssl->authmode = authmode;
}
void ssl_set_verify( ssl_context *ssl,
int (*f_vrfy)(void *, x509_cert *, int, int),
void *p_vrfy )
{
ssl->f_vrfy = f_vrfy;
ssl->p_vrfy = p_vrfy;
}
void ssl_set_rng( ssl_context *ssl,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
ssl->f_rng = f_rng;
ssl->p_rng = p_rng;
}
void ssl_set_dbg( ssl_context *ssl,
void (*f_dbg)(void *, int, const char *),
void *p_dbg )
{
ssl->f_dbg = f_dbg;
ssl->p_dbg = p_dbg;
}
void ssl_set_bio( ssl_context *ssl,
int (*f_recv)(void *, unsigned char *, size_t), void *p_recv,
int (*f_send)(void *, const unsigned char *, size_t), void *p_send )
{
ssl->f_recv = f_recv;
ssl->f_send = f_send;
ssl->p_recv = p_recv;
ssl->p_send = p_send;
}
void ssl_set_scb( ssl_context *ssl,
int (*s_get)(ssl_context *),
int (*s_set)(ssl_context *) )
{
ssl->s_get = s_get;
ssl->s_set = s_set;
}
void ssl_set_session( ssl_context *ssl, int resume, int timeout,
ssl_session *session )
{
ssl->resume = resume;
ssl->timeout = timeout;
ssl->session = session;
}
void ssl_set_ciphersuites( ssl_context *ssl, int *ciphersuites )
{
ssl->ciphersuites = ciphersuites;
}
void ssl_set_ca_chain( ssl_context *ssl, x509_cert *ca_chain,
x509_crl *ca_crl, const char *peer_cn )
{
ssl->ca_chain = ca_chain;
ssl->ca_crl = ca_crl;
ssl->peer_cn = peer_cn;
}
void ssl_set_own_cert( ssl_context *ssl, x509_cert *own_cert,
rsa_context *rsa_key )
{
ssl->own_cert = own_cert;
ssl->rsa_key = rsa_key;
}
#if defined(POLARSSL_PKCS11_C)
void ssl_set_own_cert_pkcs11( ssl_context *ssl, x509_cert *own_cert,
pkcs11_context *pkcs11_key )
{
ssl->own_cert = own_cert;
ssl->pkcs11_key = pkcs11_key;
}
#endif
int ssl_set_dh_param( ssl_context *ssl, const char *dhm_P, const char *dhm_G )
{
int ret;
if( ( ret = mpi_read_string( &ssl->dhm_ctx.P, 16, dhm_P ) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_read_string", ret );
return( ret );
}
if( ( ret = mpi_read_string( &ssl->dhm_ctx.G, 16, dhm_G ) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_read_string", ret );
return( ret );
}
return( 0 );
}
int ssl_set_dh_param_ctx( ssl_context *ssl, dhm_context *dhm_ctx )
{
int ret;
if( ( ret = mpi_copy(&ssl->dhm_ctx.P, &dhm_ctx->P) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_copy", ret );
return( ret );
}
if( ( ret = mpi_copy(&ssl->dhm_ctx.G, &dhm_ctx->G) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_copy", ret );
return( ret );
}
return( 0 );
}
int ssl_set_hostname( ssl_context *ssl, const char *hostname )
{
if( hostname == NULL )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
ssl->hostname_len = strlen( hostname );
ssl->hostname = (unsigned char *) malloc( ssl->hostname_len + 1 );
if( ssl->hostname == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
memcpy( ssl->hostname, (unsigned char *) hostname,
ssl->hostname_len );
ssl->hostname[ssl->hostname_len] = '\0';
return( 0 );
}
void ssl_set_max_version( ssl_context *ssl, int major, int minor )
{
ssl->max_major_ver = major;
ssl->max_minor_ver = minor;
}
/*
* SSL get accessors
*/
size_t ssl_get_bytes_avail( const ssl_context *ssl )
{
return( ssl->in_offt == NULL ? 0 : ssl->in_msglen );
}
int ssl_get_verify_result( const ssl_context *ssl )
{
return( ssl->verify_result );
}
const char *ssl_get_ciphersuite_name( const int ciphersuite_id )
{
switch( ciphersuite_id )
{
#if defined(POLARSSL_ARC4_C)
case SSL_RSA_RC4_128_MD5:
return( "SSL-RSA-RC4-128-MD5" );
case SSL_RSA_RC4_128_SHA:
return( "SSL-RSA-RC4-128-SHA" );
#endif
#if defined(POLARSSL_DES_C)
case SSL_RSA_DES_168_SHA:
return( "SSL-RSA-DES-168-SHA" );
case SSL_EDH_RSA_DES_168_SHA:
return( "SSL-EDH-RSA-DES-168-SHA" );
#endif
#if defined(POLARSSL_AES_C)
case SSL_RSA_AES_128_SHA:
return( "SSL-RSA-AES-128-SHA" );
case SSL_EDH_RSA_AES_128_SHA:
return( "SSL-EDH-RSA-AES-128-SHA" );
case SSL_RSA_AES_256_SHA:
return( "SSL-RSA-AES-256-SHA" );
case SSL_EDH_RSA_AES_256_SHA:
return( "SSL-EDH-RSA-AES-256-SHA" );
#endif
#if defined(POLARSSL_CAMELLIA_C)
case SSL_RSA_CAMELLIA_128_SHA:
return( "SSL-RSA-CAMELLIA-128-SHA" );
case SSL_EDH_RSA_CAMELLIA_128_SHA:
return( "SSL-EDH-RSA-CAMELLIA-128-SHA" );
case SSL_RSA_CAMELLIA_256_SHA:
return( "SSL-RSA-CAMELLIA-256-SHA" );
case SSL_EDH_RSA_CAMELLIA_256_SHA:
return( "SSL-EDH-RSA-CAMELLIA-256-SHA" );
#endif
default:
break;
}
return( "unknown" );
}
int ssl_get_ciphersuite_id( const char *ciphersuite_name )
{
#if defined(POLARSSL_ARC4_C)
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-RC4-128-MD5"))
return( SSL_RSA_RC4_128_MD5 );
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-RC4-128-SHA"))
return( SSL_RSA_RC4_128_SHA );
#endif
#if defined(POLARSSL_DES_C)
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-DES-168-SHA"))
return( SSL_RSA_DES_168_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-EDH-RSA-DES-168-SHA"))
return( SSL_EDH_RSA_DES_168_SHA );
#endif
#if defined(POLARSSL_AES_C)
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-AES-128-SHA"))
return( SSL_RSA_AES_128_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-EDH-RSA-AES-128-SHA"))
return( SSL_EDH_RSA_AES_128_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-AES-256-SHA"))
return( SSL_RSA_AES_256_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-EDH-RSA-AES-256-SHA"))
return( SSL_EDH_RSA_AES_256_SHA );
#endif
#if defined(POLARSSL_CAMELLIA_C)
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-CAMELLIA-128-SHA"))
return( SSL_RSA_CAMELLIA_128_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-EDH-RSA-CAMELLIA-128-SHA"))
return( SSL_EDH_RSA_CAMELLIA_128_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-RSA-CAMELLIA-256-SHA"))
return( SSL_RSA_CAMELLIA_256_SHA );
if (0 == strcasecmp(ciphersuite_name, "SSL-EDH-RSA-CAMELLIA-256-SHA"))
return( SSL_EDH_RSA_CAMELLIA_256_SHA );
#endif
return( 0 );
}
const char *ssl_get_ciphersuite( const ssl_context *ssl )
{
return ssl_get_ciphersuite_name( ssl->session->ciphersuite );
}
const char *ssl_get_version( const ssl_context *ssl )
{
switch( ssl->minor_ver )
{
case SSL_MINOR_VERSION_0:
return( "SSLv3.0" );
case SSL_MINOR_VERSION_1:
return( "TLSv1.0" );
case SSL_MINOR_VERSION_2:
return( "TLSv1.1" );
default:
break;
}
return( "unknown" );
}
int ssl_default_ciphersuites[] =
{
#if defined(POLARSSL_DHM_C)
#if defined(POLARSSL_AES_C)
SSL_EDH_RSA_AES_128_SHA,
SSL_EDH_RSA_AES_256_SHA,
#endif
#if defined(POLARSSL_CAMELLIA_C)
SSL_EDH_RSA_CAMELLIA_128_SHA,
SSL_EDH_RSA_CAMELLIA_256_SHA,
#endif
#if defined(POLARSSL_DES_C)
SSL_EDH_RSA_DES_168_SHA,
#endif
#endif
#if defined(POLARSSL_AES_C)
SSL_RSA_AES_256_SHA,
#endif
#if defined(POLARSSL_CAMELLIA_C)
SSL_RSA_CAMELLIA_256_SHA,
#endif
#if defined(POLARSSL_AES_C)
SSL_RSA_AES_128_SHA,
#endif
#if defined(POLARSSL_CAMELLIA_C)
SSL_RSA_CAMELLIA_128_SHA,
#endif
#if defined(POLARSSL_DES_C)
SSL_RSA_DES_168_SHA,
#endif
#if defined(POLARSSL_ARC4_C)
SSL_RSA_RC4_128_SHA,
SSL_RSA_RC4_128_MD5,
#endif
0
};
/*
* Perform the SSL handshake
*/
int ssl_handshake( ssl_context *ssl )
{
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
SSL_DEBUG_MSG( 2, ( "=> handshake" ) );
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
ret = ssl_handshake_client( ssl );
#endif
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
ret = ssl_handshake_server( ssl );
#endif
SSL_DEBUG_MSG( 2, ( "<= handshake" ) );
return( ret );
}
/*
* Receive application data decrypted from the SSL layer
*/
int ssl_read( ssl_context *ssl, unsigned char *buf, size_t len )
{
int ret;
size_t n;
SSL_DEBUG_MSG( 2, ( "=> read" ) );
if( ssl->state != SSL_HANDSHAKE_OVER )
{
if( ( ret = ssl_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
}
if( ssl->in_offt == NULL )
{
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
if( ret == POLARSSL_ERR_SSL_CONN_EOF )
return( 0 );
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
if( ssl->in_msglen == 0 &&
ssl->in_msgtype == SSL_MSG_APPLICATION_DATA )
{
/*
* OpenSSL sends empty messages to randomize the IV
*/
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
if( ret == POLARSSL_ERR_SSL_CONN_EOF )
return( 0 );
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
}
if( ssl->in_msgtype != SSL_MSG_APPLICATION_DATA )
{
SSL_DEBUG_MSG( 1, ( "bad application data message" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
ssl->in_offt = ssl->in_msg;
}
n = ( len < ssl->in_msglen )
? len : ssl->in_msglen;
memcpy( buf, ssl->in_offt, n );
ssl->in_msglen -= n;
if( ssl->in_msglen == 0 )
/* all bytes consumed */
ssl->in_offt = NULL;
else
/* more data available */
ssl->in_offt += n;
SSL_DEBUG_MSG( 2, ( "<= read" ) );
return( (int) n );
}
/*
* Send application data to be encrypted by the SSL layer
*/
int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
{
int ret;
size_t n;
SSL_DEBUG_MSG( 2, ( "=> write" ) );
if( ssl->state != SSL_HANDSHAKE_OVER )
{
if( ( ret = ssl_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
}
n = ( len < SSL_MAX_CONTENT_LEN )
? len : SSL_MAX_CONTENT_LEN;
if( ssl->out_left != 0 )
{
if( ( ret = ssl_flush_output( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_flush_output", ret );
return( ret );
}
}
else
{
ssl->out_msglen = n;
ssl->out_msgtype = SSL_MSG_APPLICATION_DATA;
memcpy( ssl->out_msg, buf, n );
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
}
SSL_DEBUG_MSG( 2, ( "<= write" ) );
return( (int) n );
}
/*
* Notify the peer that the connection is being closed
*/
int ssl_close_notify( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> write close notify" ) );
if( ( ret = ssl_flush_output( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_flush_output", ret );
return( ret );
}
if( ssl->state == SSL_HANDSHAKE_OVER )
{
ssl->out_msgtype = SSL_MSG_ALERT;
ssl->out_msglen = 2;
ssl->out_msg[0] = SSL_ALERT_LEVEL_WARNING;
ssl->out_msg[1] = SSL_ALERT_MSG_CLOSE_NOTIFY;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
}
SSL_DEBUG_MSG( 2, ( "<= write close notify" ) );
return( ret );
}
/*
* Free an SSL context
*/
void ssl_free( ssl_context *ssl )
{
SSL_DEBUG_MSG( 2, ( "=> free" ) );
if( ssl->peer_cert != NULL )
{
x509_free( ssl->peer_cert );
memset( ssl->peer_cert, 0, sizeof( x509_cert ) );
free( ssl->peer_cert );
}
if( ssl->out_ctr != NULL )
{
memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
free( ssl->out_ctr );
}
if( ssl->in_ctr != NULL )
{
memset( ssl->in_ctr, 0, SSL_BUFFER_LEN );
free( ssl->in_ctr );
}
#if defined(POLARSSL_DHM_C)
dhm_free( &ssl->dhm_ctx );
#endif
if ( ssl->hostname != NULL)
{
memset( ssl->hostname, 0, ssl->hostname_len );
free( ssl->hostname );
ssl->hostname_len = 0;
}
SSL_DEBUG_MSG( 2, ( "<= free" ) );
/* Actually clear after last debug message */
memset( ssl, 0, sizeof( ssl_context ) );
}
#endif