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/*
* SSLv3/TLSv1 shared functions
*
* Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
*
* This file is part of mbed TLS (https://polarssl.org)
*
* 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(POLARSSL_CONFIG_FILE)
#include "polarssl/config.h"
#else
#include POLARSSL_CONFIG_FILE
#endif
#if defined(POLARSSL_SSL_TLS_C)
#include "polarssl/debug.h"
#include "polarssl/ssl.h"
#include <string.h>
#if defined(POLARSSL_X509_CRT_PARSE_C) && \
defined(POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE)
#include "polarssl/oid.h"
#endif
#if defined(POLARSSL_PLATFORM_C)
#include "polarssl/platform.h"
#else
#include <stdlib.h>
#define polarssl_malloc malloc
#define polarssl_free free
#endif
#if defined(_MSC_VER) && !defined strcasecmp && !defined(EFIX64) && \
!defined(EFI32)
#define strcasecmp _stricmp
#endif
/* Implementation that should never be optimized out by the compiler */
static void polarssl_zeroize( void *v, size_t n ) {
volatile unsigned char *p = v; while( n-- ) *p++ = 0;
}
#if defined(POLARSSL_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 mfl_code_to_length[SSL_MAX_FRAG_LEN_INVALID] =
{
SSL_MAX_CONTENT_LEN, /* SSL_MAX_FRAG_LEN_NONE */
512, /* SSL_MAX_FRAG_LEN_512 */
1024, /* SSL_MAX_FRAG_LEN_1024 */
2048, /* SSL_MAX_FRAG_LEN_2048 */
4096, /* SSL_MAX_FRAG_LEN_4096 */
};
#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
static int ssl_session_copy( ssl_session *dst, const ssl_session *src )
{
ssl_session_free( dst );
memcpy( dst, src, sizeof( ssl_session ) );
#if defined(POLARSSL_X509_CRT_PARSE_C)
if( src->peer_cert != NULL )
{
int ret;
dst->peer_cert = (x509_crt *) polarssl_malloc( sizeof(x509_crt) );
if( dst->peer_cert == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
x509_crt_init( dst->peer_cert );
if( ( ret = x509_crt_parse_der( dst->peer_cert, src->peer_cert->raw.p,
src->peer_cert->raw.len ) ) != 0 )
{
polarssl_free( dst->peer_cert );
dst->peer_cert = NULL;
return( ret );
}
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
#if defined(POLARSSL_SSL_SESSION_TICKETS)
if( src->ticket != NULL )
{
dst->ticket = (unsigned char *) polarssl_malloc( src->ticket_len );
if( dst->ticket == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
memcpy( dst->ticket, src->ticket, src->ticket_len );
}
#endif /* POLARSSL_SSL_SESSION_TICKETS */
return( 0 );
}
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
int (*ssl_hw_record_init)( 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 (*ssl_hw_record_activate)( ssl_context *ssl, int direction) = NULL;
int (*ssl_hw_record_reset)( ssl_context *ssl ) = NULL;
int (*ssl_hw_record_write)( ssl_context *ssl ) = NULL;
int (*ssl_hw_record_read)( ssl_context *ssl ) = NULL;
int (*ssl_hw_record_finish)( ssl_context *ssl ) = NULL;
#endif /* POLARSSL_SSL_HW_RECORD_ACCEL */
/*
* Key material generation
*/
#if defined(POLARSSL_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 )
{
size_t i;
md5_context md5;
sha1_context sha1;
unsigned char padding[16];
unsigned char sha1sum[20];
((void)label);
md5_init( &md5 );
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 );
sha1_starts( &sha1 );
sha1_update( &sha1, padding, 1 + i );
sha1_update( &sha1, secret, slen );
sha1_update( &sha1, random, rlen );
sha1_finish( &sha1, sha1sum );
md5_starts( &md5 );
md5_update( &md5, secret, slen );
md5_update( &md5, sha1sum, 20 );
md5_finish( &md5, dstbuf + i * 16 );
}
md5_free( &md5 );
sha1_free( &sha1 );
polarssl_zeroize( padding, sizeof( padding ) );
polarssl_zeroize( sha1sum, sizeof( sha1sum ) );
return( 0 );
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_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];
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] );
}
polarssl_zeroize( tmp, sizeof( tmp ) );
polarssl_zeroize( h_i, sizeof( h_i ) );
return( 0 );
}
#endif /* POLARSSL_SSL_PROTO_TLS1) || POLARSSL_SSL_PROTO_TLS1_1 */
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_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 )
{
size_t nb;
size_t i, j, k;
unsigned char tmp[128];
unsigned char h_i[32];
if( sizeof( tmp ) < 32 + strlen( label ) + rlen )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
nb = strlen( label );
memcpy( tmp + 32, label, nb );
memcpy( tmp + 32 + nb, random, rlen );
nb += rlen;
/*
* Compute P_<hash>(secret, label + random)[0..dlen]
*/
sha256_hmac( secret, slen, tmp + 32, nb, tmp, 0 );
for( i = 0; i < dlen; i += 32 )
{
sha256_hmac( secret, slen, tmp, 32 + nb, h_i, 0 );
sha256_hmac( secret, slen, tmp, 32, tmp, 0 );
k = ( i + 32 > dlen ) ? dlen % 32 : 32;
for( j = 0; j < k; j++ )
dstbuf[i + j] = h_i[j];
}
polarssl_zeroize( tmp, sizeof( tmp ) );
polarssl_zeroize( h_i, sizeof( h_i ) );
return( 0 );
}
#endif /* POLARSSL_SHA256_C */
#if defined(POLARSSL_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 )
{
size_t nb;
size_t i, j, k;
unsigned char tmp[128];
unsigned char h_i[48];
if( sizeof( tmp ) < 48 + strlen( label ) + rlen )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
nb = strlen( label );
memcpy( tmp + 48, label, nb );
memcpy( tmp + 48 + nb, random, rlen );
nb += rlen;
/*
* Compute P_<hash>(secret, label + random)[0..dlen]
*/
sha512_hmac( secret, slen, tmp + 48, nb, tmp, 1 );
for( i = 0; i < dlen; i += 48 )
{
sha512_hmac( secret, slen, tmp, 48 + nb, h_i, 1 );
sha512_hmac( secret, slen, tmp, 48, tmp, 1 );
k = ( i + 48 > dlen ) ? dlen % 48 : 48;
for( j = 0; j < k; j++ )
dstbuf[i + j] = h_i[j];
}
polarssl_zeroize( tmp, sizeof( tmp ) );
polarssl_zeroize( h_i, sizeof( h_i ) );
return( 0 );
}
#endif /* POLARSSL_SHA512_C */
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
static void ssl_update_checksum_start( ssl_context *, const unsigned char *, size_t );
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1) || \
defined(POLARSSL_SSL_PROTO_TLS1_1)
static void ssl_update_checksum_md5sha1( ssl_context *, const unsigned char *, size_t );
#endif
#if defined(POLARSSL_SSL_PROTO_SSL3)
static void ssl_calc_verify_ssl( ssl_context *, unsigned char * );
static void ssl_calc_finished_ssl( ssl_context *, unsigned char *, int );
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1)
static void ssl_calc_verify_tls( ssl_context *, unsigned char * );
static void ssl_calc_finished_tls( ssl_context *, unsigned char *, int );
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
static void ssl_update_checksum_sha256( ssl_context *, const unsigned char *, size_t );
static void ssl_calc_verify_tls_sha256( ssl_context *,unsigned char * );
static void ssl_calc_finished_tls_sha256( ssl_context *,unsigned char *, int );
#endif
#if defined(POLARSSL_SHA512_C)
static void ssl_update_checksum_sha384( ssl_context *, const unsigned char *, size_t );
static void ssl_calc_verify_tls_sha384( ssl_context *, unsigned char * );
static void ssl_calc_finished_tls_sha384( ssl_context *, unsigned char *, int );
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
int ssl_derive_keys( 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 iv_copy_len;
const cipher_info_t *cipher_info;
const md_info_t *md_info;
ssl_session *session = ssl->session_negotiate;
ssl_transform *transform = ssl->transform_negotiate;
ssl_handshake_params *handshake = ssl->handshake;
SSL_DEBUG_MSG( 2, ( "=> derive keys" ) );
cipher_info = cipher_info_from_type( transform->ciphersuite_info->cipher );
if( cipher_info == NULL )
{
SSL_DEBUG_MSG( 1, ( "cipher info for %d not found",
transform->ciphersuite_info->cipher ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
md_info = md_info_from_type( transform->ciphersuite_info->mac );
if( md_info == NULL )
{
SSL_DEBUG_MSG( 1, ( "md info for %d not found",
transform->ciphersuite_info->mac ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
/*
* Set appropriate PRF function and other SSL / TLS / TLS1.2 functions
*/
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == 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(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1)
if( ssl->minor_ver < 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(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA512_C)
if( ssl->minor_ver == SSL_MINOR_VERSION_3 &&
transform->ciphersuite_info->mac == POLARSSL_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(POLARSSL_SHA256_C)
if( ssl->minor_ver == 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 /* POLARSSL_SSL_PROTO_TLS1_2 */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_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 )
{
SSL_DEBUG_BUF( 3, "premaster secret", handshake->premaster,
handshake->pmslen );
#if defined(POLARSSL_SSL_EXTENDED_MASTER_SECRET)
if( ssl->handshake->extended_ms == SSL_EXTENDED_MS_ENABLED )
{
unsigned char session_hash[48];
size_t hash_len;
SSL_DEBUG_MSG( 3, ( "using extended master secret" ) );
ssl->handshake->calc_verify( ssl, session_hash );
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == SSL_MINOR_VERSION_3 )
{
#if defined(POLARSSL_SHA512_C)
if( ssl->transform_negotiate->ciphersuite_info->mac ==
POLARSSL_MD_SHA384 )
{
hash_len = 48;
}
else
#endif
hash_len = 32;
}
else
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
hash_len = 36;
SSL_DEBUG_BUF( 3, "session hash", session_hash, hash_len );
handshake->tls_prf( handshake->premaster, handshake->pmslen,
"extended master secret",
session_hash, hash_len, session->master, 48 );
}
else
#endif
handshake->tls_prf( handshake->premaster, handshake->pmslen,
"master secret",
handshake->randbytes, 64, session->master, 48 );
polarssl_zeroize( handshake->premaster, sizeof(handshake->premaster) );
}
else
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 );
polarssl_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 )
*/
handshake->tls_prf( session->master, 48, "key expansion",
handshake->randbytes, 64, keyblk, 256 );
SSL_DEBUG_MSG( 3, ( "ciphersuite = %s",
ssl_get_ciphersuite_name( session->ciphersuite ) ) );
SSL_DEBUG_BUF( 3, "master secret", session->master, 48 );
SSL_DEBUG_BUF( 4, "random bytes", handshake->randbytes, 64 );
SSL_DEBUG_BUF( 4, "key block", keyblk, 256 );
polarssl_zeroize( handshake->randbytes, sizeof( handshake->randbytes ) );
/*
* Determine the appropriate key, IV and MAC length.
*/
transform->keylen = cipher_info->key_length / 8;
if( cipher_info->mode == POLARSSL_MODE_GCM ||
cipher_info->mode == POLARSSL_MODE_CCM )
{
transform->maclen = 0;
transform->ivlen = 12;
transform->fixed_ivlen = 4;
/* Minimum length is expicit IV + tag */
transform->minlen = transform->ivlen - transform->fixed_ivlen
+ ( transform->ciphersuite_info->flags &
POLARSSL_CIPHERSUITE_SHORT_TAG ? 8 : 16 );
}
else
{
int ret;
/* Initialize HMAC contexts */
if( ( ret = md_init_ctx( &transform->md_ctx_enc, md_info ) ) != 0 ||
( ret = md_init_ctx( &transform->md_ctx_dec, md_info ) ) != 0 )
{
SSL_DEBUG_RET( 1, "md_init_ctx", ret );
return( ret );
}
/* Get MAC length */
transform->maclen = md_get_size( md_info );
#if defined(POLARSSL_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 == SSL_TRUNC_HMAC_ENABLED )
transform->maclen = SSL_TRUNCATED_HMAC_LEN;
#endif /* POLARSSL_SSL_TRUNCATED_HMAC */
/* IV length */
transform->ivlen = cipher_info->iv_size;
/* Minimum length */
if( cipher_info->mode == POLARSSL_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(POLARSSL_SSL_ENCRYPT_THEN_MAC)
if( session->encrypt_then_mac == 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(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 ||
ssl->minor_ver == SSL_MINOR_VERSION_1 )
; /* No need to adjust minlen */
else
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_1) || defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == SSL_MINOR_VERSION_2 ||
ssl->minor_ver == SSL_MINOR_VERSION_3 )
{
transform->minlen += transform->ivlen;
}
else
#endif
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
}
}
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(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
{
key1 = keyblk + transform->maclen * 2;
key2 = keyblk + transform->maclen * 2 + transform->keylen;
mac_enc = keyblk;
mac_dec = keyblk + transform->maclen;
/*
* 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 /* POLARSSL_SSL_CLI_C */
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
{
key1 = keyblk + transform->maclen * 2 + transform->keylen;
key2 = keyblk + transform->maclen * 2;
mac_enc = keyblk + transform->maclen;
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 /* POLARSSL_SSL_SRV_C */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( transform->maclen > sizeof transform->mac_enc )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
memcpy( transform->mac_enc, mac_enc, transform->maclen );
memcpy( transform->mac_dec, mac_dec, transform->maclen );
}
else
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= SSL_MINOR_VERSION_1 )
{
md_hmac_starts( &transform->md_ctx_enc, mac_enc, transform->maclen );
md_hmac_starts( &transform->md_ctx_dec, mac_dec, transform->maclen );
}
else
#endif
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_init != NULL )
{
int ret = 0;
SSL_DEBUG_MSG( 2, ( "going for ssl_hw_record_init()" ) );
if( ( ret = ssl_hw_record_init( ssl, key1, key2, transform->keylen,
transform->iv_enc, transform->iv_dec,
iv_copy_len,
mac_enc, mac_dec,
transform->maclen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_init", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif /* POLARSSL_SSL_HW_RECORD_ACCEL */
if( ( ret = cipher_init_ctx( &transform->cipher_ctx_enc,
cipher_info ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_init_ctx", ret );
return( ret );
}
if( ( ret = cipher_init_ctx( &transform->cipher_ctx_dec,
cipher_info ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_init_ctx", ret );
return( ret );
}
if( ( ret = cipher_setkey( &transform->cipher_ctx_enc, key1,
cipher_info->key_length,
POLARSSL_ENCRYPT ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_setkey", ret );
return( ret );
}
if( ( ret = cipher_setkey( &transform->cipher_ctx_dec, key2,
cipher_info->key_length,
POLARSSL_DECRYPT ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_setkey", ret );
return( ret );
}
#if defined(POLARSSL_CIPHER_MODE_CBC)
if( cipher_info->mode == POLARSSL_MODE_CBC )
{
if( ( ret = cipher_set_padding_mode( &transform->cipher_ctx_enc,
POLARSSL_PADDING_NONE ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_set_padding_mode", ret );
return( ret );
}
if( ( ret = cipher_set_padding_mode( &transform->cipher_ctx_dec,
POLARSSL_PADDING_NONE ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_set_padding_mode", ret );
return( ret );
}
}
#endif /* POLARSSL_CIPHER_MODE_CBC */
polarssl_zeroize( keyblk, sizeof( keyblk ) );
#if defined(POLARSSL_ZLIB_SUPPORT)
// Initialize compression
//
if( session->compression == SSL_COMPRESS_DEFLATE )
{
if( ssl->compress_buf == NULL )
{
SSL_DEBUG_MSG( 3, ( "Allocating compression buffer" ) );
ssl->compress_buf = polarssl_malloc( SSL_BUFFER_LEN );
if( ssl->compress_buf == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed",
SSL_BUFFER_LEN ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
}
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 )
{
SSL_DEBUG_MSG( 1, ( "Failed to initialize compression" ) );
return( POLARSSL_ERR_SSL_COMPRESSION_FAILED );
}
}
#endif /* POLARSSL_ZLIB_SUPPORT */
SSL_DEBUG_MSG( 2, ( "<= derive keys" ) );
return( 0 );
}
#if defined(POLARSSL_SSL_PROTO_SSL3)
void ssl_calc_verify_ssl( 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 ssl" ) );
memcpy( &md5 , &ssl->handshake->fin_md5 , sizeof(md5_context) );
memcpy( &sha1, &ssl->handshake->fin_sha1, sizeof(sha1_context) );
memset( pad_1, 0x36, 48 );
memset( pad_2, 0x5C, 48 );
md5_update( &md5, ssl->session_negotiate->master, 48 );
md5_update( &md5, pad_1, 48 );
md5_finish( &md5, hash );
md5_starts( &md5 );
md5_update( &md5, ssl->session_negotiate->master, 48 );
md5_update( &md5, pad_2, 48 );
md5_update( &md5, hash, 16 );
md5_finish( &md5, hash );
sha1_update( &sha1, ssl->session_negotiate->master, 48 );
sha1_update( &sha1, pad_1, 40 );
sha1_finish( &sha1, hash + 16 );
sha1_starts( &sha1 );
sha1_update( &sha1, ssl->session_negotiate->master, 48 );
sha1_update( &sha1, pad_2, 40 );
sha1_update( &sha1, hash + 16, 20 );
sha1_finish( &sha1, hash + 16 );
SSL_DEBUG_BUF( 3, "calculated verify result", hash, 36 );
SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
md5_free( &md5 );
sha1_free( &sha1 );
return;
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1)
void ssl_calc_verify_tls( ssl_context *ssl, unsigned char hash[36] )
{
md5_context md5;
sha1_context sha1;
SSL_DEBUG_MSG( 2, ( "=> calc verify tls" ) );
memcpy( &md5 , &ssl->handshake->fin_md5 , sizeof(md5_context) );
memcpy( &sha1, &ssl->handshake->fin_sha1, sizeof(sha1_context) );
md5_finish( &md5, hash );
sha1_finish( &sha1, hash + 16 );
SSL_DEBUG_BUF( 3, "calculated verify result", hash, 36 );
SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
md5_free( &md5 );
sha1_free( &sha1 );
return;
}
#endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 */
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
void ssl_calc_verify_tls_sha256( ssl_context *ssl, unsigned char hash[32] )
{
sha256_context sha256;
SSL_DEBUG_MSG( 2, ( "=> calc verify sha256" ) );
memcpy( &sha256, &ssl->handshake->fin_sha256, sizeof(sha256_context) );
sha256_finish( &sha256, hash );
SSL_DEBUG_BUF( 3, "calculated verify result", hash, 32 );
SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
sha256_free( &sha256 );
return;
}
#endif /* POLARSSL_SHA256_C */
#if defined(POLARSSL_SHA512_C)
void ssl_calc_verify_tls_sha384( ssl_context *ssl, unsigned char hash[48] )
{
sha512_context sha512;
SSL_DEBUG_MSG( 2, ( "=> calc verify sha384" ) );
memcpy( &sha512, &ssl->handshake->fin_sha512, sizeof(sha512_context) );
sha512_finish( &sha512, hash );
SSL_DEBUG_BUF( 3, "calculated verify result", hash, 48 );
SSL_DEBUG_MSG( 2, ( "<= calc verify" ) );
sha512_free( &sha512 );
return;
}
#endif /* POLARSSL_SHA512_C */
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
int ssl_psk_derive_premaster( ssl_context *ssl, key_exchange_type_t key_ex )
{
unsigned char *p = ssl->handshake->premaster;
unsigned char *end = p + sizeof( ssl->handshake->premaster );
/*
* 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(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
if( key_ex == POLARSSL_KEY_EXCHANGE_PSK )
{
if( end - p < 2 + (int) ssl->psk_len )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( ssl->psk_len >> 8 );
*(p++) = (unsigned char)( ssl->psk_len );
p += ssl->psk_len;
}
else
#endif /* POLARSSL_KEY_EXCHANGE_PSK_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED)
if( key_ex == POLARSSL_KEY_EXCHANGE_RSA_PSK )
{
/*
* other_secret already set by the ClientKeyExchange message,
* and is 48 bytes long
*/
*p++ = 0;
*p++ = 48;
p += 48;
}
else
#endif /* POLARSSL_KEY_EXCHANGE_RSA_PKS_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED)
if( key_ex == POLARSSL_KEY_EXCHANGE_DHE_PSK )
{
int ret;
size_t len = end - ( p + 2 );
/* Write length only when we know the actual value */
if( ( ret = dhm_calc_secret( &ssl->handshake->dhm_ctx,
p + 2, &len,
ssl->f_rng, ssl->p_rng ) ) != 0 )
{
SSL_DEBUG_RET( 1, "dhm_calc_secret", ret );
return( ret );
}
*(p++) = (unsigned char)( len >> 8 );
*(p++) = (unsigned char)( len );
p += len;
SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K );
}
else
#endif /* POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( key_ex == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
int ret;
size_t zlen;
if( ( ret = ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &zlen,
p + 2, end - ( p + 2 ),
ssl->f_rng, ssl->p_rng ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ecdh_calc_secret", ret );
return( ret );
}
*(p++) = (unsigned char)( zlen >> 8 );
*(p++) = (unsigned char)( zlen );
p += zlen;
SSL_DEBUG_MPI( 3, "ECDH: z", &ssl->handshake->ecdh_ctx.z );
}
else
#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
/* opaque psk<0..2^16-1>; */
if( end - p < 2 + (int) ssl->psk_len )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
*(p++) = (unsigned char)( ssl->psk_len >> 8 );
*(p++) = (unsigned char)( ssl->psk_len );
memcpy( p, ssl->psk, ssl->psk_len );
p += ssl->psk_len;
ssl->handshake->pmslen = p - ssl->handshake->premaster;
return( 0 );
}
#endif /* POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(POLARSSL_SSL_PROTO_SSL3)
/*
* SSLv3.0 MAC functions
*/
static void ssl_mac( md_context_t *md_ctx, unsigned char *secret,
unsigned char *buf, size_t len,
unsigned char *ctr, int type )
{
unsigned char header[11];
unsigned char padding[48];
int padlen;
int md_size = md_get_size( md_ctx->md_info );
int md_type = md_get_type( md_ctx->md_info );
/* Only MD5 and SHA-1 supported */
if( md_type == POLARSSL_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 );
md_starts( md_ctx );
md_update( md_ctx, secret, md_size );
md_update( md_ctx, padding, padlen );
md_update( md_ctx, header, 11 );
md_update( md_ctx, buf, len );
md_finish( md_ctx, buf + len );
memset( padding, 0x5C, padlen );
md_starts( md_ctx );
md_update( md_ctx, secret, md_size );
md_update( md_ctx, padding, padlen );
md_update( md_ctx, buf + len, md_size );
md_finish( md_ctx, buf + len );
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_ARC4_C) || defined(POLARSSL_CIPHER_NULL_CIPHER) || \
( defined(POLARSSL_CIPHER_MODE_CBC) && \
( defined(POLARSSL_AES_C) || defined(POLARSSL_CAMELLIA_C) ) )
#define POLARSSL_SOME_MODES_USE_MAC
#endif
/*
* Encryption/decryption functions
*/
static int ssl_encrypt_buf( ssl_context *ssl )
{
size_t i;
cipher_mode_t mode;
int auth_done = 0;
SSL_DEBUG_MSG( 2, ( "=> encrypt buf" ) );
if( ssl->session_out == NULL || ssl->transform_out == NULL )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
mode = cipher_get_cipher_mode( &ssl->transform_out->cipher_ctx_enc );
SSL_DEBUG_BUF( 4, "before encrypt: output payload",
ssl->out_msg, ssl->out_msglen );
/*
* Add MAC before if needed
*/
#if defined(POLARSSL_SOME_MODES_USE_MAC)
if( mode == POLARSSL_MODE_STREAM ||
( mode == POLARSSL_MODE_CBC
#if defined(POLARSSL_SSL_ENCRYPT_THEN_MAC)
&& ssl->session_out->encrypt_then_mac == SSL_ETM_DISABLED
#endif
) )
{
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
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 );
}
else
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= SSL_MINOR_VERSION_1 )
{
md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_ctr, 13 );
md_hmac_update( &ssl->transform_out->md_ctx_enc,
ssl->out_msg, ssl->out_msglen );
md_hmac_finish( &ssl->transform_out->md_ctx_enc,
ssl->out_msg + ssl->out_msglen );
md_hmac_reset( &ssl->transform_out->md_ctx_enc );
}
else
#endif
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
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(POLARSSL_ARC4_C) || defined(POLARSSL_CIPHER_NULL_CIPHER)
if( mode == POLARSSL_MODE_STREAM )
{
int ret;
size_t olen = 0;
SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of padding",
ssl->out_msglen, 0 ) );
if( ( ret = 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 )
{
SSL_DEBUG_RET( 1, "cipher_crypt", ret );
return( ret );
}
if( ssl->out_msglen != olen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* POLARSSL_ARC4_C || POLARSSL_CIPHER_NULL_CIPHER */
#if defined(POLARSSL_GCM_C) || defined(POLARSSL_CCM_C)
if( mode == POLARSSL_MODE_GCM ||
mode == POLARSSL_MODE_CCM )
{
int ret;
size_t enc_msglen, olen;
unsigned char *enc_msg;
unsigned char add_data[13];
unsigned char taglen = ssl->transform_out->ciphersuite_info->flags &
POLARSSL_CIPHERSUITE_SHORT_TAG ? 8 : 16;
memcpy( add_data, ssl->out_ctr, 8 );
add_data[8] = ssl->out_msgtype;
add_data[9] = ssl->major_ver;
add_data[10] = ssl->minor_ver;
add_data[11] = ( ssl->out_msglen >> 8 ) & 0xFF;
add_data[12] = ssl->out_msglen & 0xFF;
SSL_DEBUG_BUF( 4, "additional data used for AEAD",
add_data, 13 );
/*
* Generate IV
*/
#if defined(POLARSSL_SSL_AEAD_RANDOM_IV)
ret = ssl->f_rng( ssl->p_rng,
ssl->transform_out->iv_enc + ssl->transform_out->fixed_ivlen,
ssl->transform_out->ivlen - ssl->transform_out->fixed_ivlen );
if( ret != 0 )
return( ret );
memcpy( ssl->out_iv,
ssl->transform_out->iv_enc + ssl->transform_out->fixed_ivlen,
ssl->transform_out->ivlen - ssl->transform_out->fixed_ivlen );
#else
if( ssl->transform_out->ivlen - ssl->transform_out->fixed_ivlen != 8 )
{
/* Reminder if we ever add an AEAD mode with a different size */
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
memcpy( ssl->transform_out->iv_enc + ssl->transform_out->fixed_ivlen,
ssl->out_ctr, 8 );
memcpy( ssl->out_iv, ssl->out_ctr, 8 );
#endif
SSL_DEBUG_BUF( 4, "IV used", ssl->out_iv,
ssl->transform_out->ivlen - ssl->transform_out->fixed_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 -
ssl->transform_out->fixed_ivlen;
SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
"including %d bytes of padding",
ssl->out_msglen, 0 ) );
/*
* Encrypt and authenticate
*/
if( ( ret = cipher_auth_encrypt( &ssl->transform_out->cipher_ctx_enc,
ssl->transform_out->iv_enc,
ssl->transform_out->ivlen,
add_data, 13,
enc_msg, enc_msglen,
enc_msg, &olen,
enc_msg + enc_msglen, taglen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_auth_encrypt", ret );
return( ret );
}
if( olen != enc_msglen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
ssl->out_msglen += taglen;
auth_done++;
SSL_DEBUG_BUF( 4, "after encrypt: tag", enc_msg + enc_msglen, taglen );
}
else
#endif /* POLARSSL_GCM_C || POLARSSL_CCM_C */
#if defined(POLARSSL_CIPHER_MODE_CBC) && \
( defined(POLARSSL_AES_C) || defined(POLARSSL_CAMELLIA_C) )
if( mode == POLARSSL_MODE_CBC )
{
int ret;
unsigned char *enc_msg;
size_t enc_msglen, padlen, olen = 0;
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(POLARSSL_SSL_PROTO_TLS1_1) || defined(POLARSSL_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 >= SSL_MINOR_VERSION_2 )
{
/*
* Generate IV
*/
int ret = ssl->f_rng( ssl->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 /* POLARSSL_SSL_PROTO_TLS1_1 || POLARSSL_SSL_PROTO_TLS1_2 */
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 = 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 )
{
SSL_DEBUG_RET( 1, "cipher_crypt", ret );
return( ret );
}
if( enc_msglen != olen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1)
if( ssl->minor_ver < 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(POLARSSL_SSL_ENCRYPT_THEN_MAC)
if( auth_done == 0 )
{
/*
* 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];
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 );
SSL_DEBUG_BUF( 4, "MAC'd meta-data", pseudo_hdr, 13 );
md_hmac_update( &ssl->transform_out->md_ctx_enc, pseudo_hdr, 13 );
md_hmac_update( &ssl->transform_out->md_ctx_enc,
ssl->out_iv, ssl->out_msglen );
md_hmac_finish( &ssl->transform_out->md_ctx_enc,
ssl->out_iv + ssl->out_msglen );
md_hmac_reset( &ssl->transform_out->md_ctx_enc );
ssl->out_msglen += ssl->transform_out->maclen;
auth_done++;
}
#endif /* POLARSSL_SSL_ENCRYPT_THEN_MAC */
}
else
#endif /* POLARSSL_CIPHER_MODE_CBC &&
( POLARSSL_AES_C || POLARSSL_CAMELLIA_C ) */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
/* Make extra sure authentication was performed, exactly once */
if( auth_done != 1 )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
for( i = 8; i > 0; i-- )
if( ++ssl->out_ctr[i - 1] != 0 )
break;
/* The loops goes to its end iff the counter is wrapping */
if( i == 0 )
{
SSL_DEBUG_MSG( 1, ( "outgoing message counter would wrap" ) );
return( POLARSSL_ERR_SSL_COUNTER_WRAPPING );
}
SSL_DEBUG_MSG( 2, ( "<= encrypt buf" ) );
return( 0 );
}
#define POLARSSL_SSL_MAX_MAC_SIZE 48
static int ssl_decrypt_buf( ssl_context *ssl )
{
size_t i;
cipher_mode_t mode;
int auth_done = 0;
#if defined(POLARSSL_SOME_MODES_USE_MAC)
size_t padlen = 0, correct = 1;
#endif
SSL_DEBUG_MSG( 2, ( "=> decrypt buf" ) );
if( ssl->session_in == NULL || ssl->transform_in == NULL )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
mode = cipher_get_cipher_mode( &ssl->transform_in->cipher_ctx_dec );
if( ssl->in_msglen < ssl->transform_in->minlen )
{
SSL_DEBUG_MSG( 1, ( "in_msglen (%d) < minlen (%d)",
ssl->in_msglen, ssl->transform_in->minlen ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
#if defined(POLARSSL_ARC4_C) || defined(POLARSSL_CIPHER_NULL_CIPHER)
if( mode == POLARSSL_MODE_STREAM )
{
int ret;
size_t olen = 0;
padlen = 0;
if( ( ret = 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 )
{
SSL_DEBUG_RET( 1, "cipher_crypt", ret );
return( ret );
}
if( ssl->in_msglen != olen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* POLARSSL_ARC4_C || POLARSSL_CIPHER_NULL_CIPHER */
#if defined(POLARSSL_GCM_C) || defined(POLARSSL_CCM_C)
if( mode == POLARSSL_MODE_GCM ||
mode == POLARSSL_MODE_CCM )
{
int ret;
size_t dec_msglen, olen;
unsigned char *dec_msg;
unsigned char *dec_msg_result;
unsigned char add_data[13];
unsigned char taglen = ssl->transform_in->ciphersuite_info->flags &
POLARSSL_CIPHERSUITE_SHORT_TAG ? 8 : 16;
unsigned char explicit_iv_len = ssl->transform_in->ivlen -
ssl->transform_in->fixed_ivlen;
if( ssl->in_msglen < explicit_iv_len + taglen )
{
SSL_DEBUG_MSG( 1, ( "msglen (%d) < explicit_iv_len (%d) "
"+ taglen (%d)", ssl->in_msglen,
explicit_iv_len, taglen ) );
return( POLARSSL_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;
memcpy( add_data, ssl->in_ctr, 8 );
add_data[8] = ssl->in_msgtype;
add_data[9] = ssl->major_ver;
add_data[10] = ssl->minor_ver;
add_data[11] = ( ssl->in_msglen >> 8 ) & 0xFF;
add_data[12] = ssl->in_msglen & 0xFF;
SSL_DEBUG_BUF( 4, "additional data used for AEAD",
add_data, 13 );
memcpy( ssl->transform_in->iv_dec + ssl->transform_in->fixed_ivlen,
ssl->in_iv,
ssl->transform_in->ivlen - ssl->transform_in->fixed_ivlen );
SSL_DEBUG_BUF( 4, "IV used", ssl->transform_in->iv_dec,
ssl->transform_in->ivlen );
SSL_DEBUG_BUF( 4, "TAG used", dec_msg + dec_msglen, taglen );
/*
* Decrypt and authenticate
*/
if( ( ret = cipher_auth_decrypt( &ssl->transform_in->cipher_ctx_dec,
ssl->transform_in->iv_dec,
ssl->transform_in->ivlen,
add_data, 13,
dec_msg, dec_msglen,
dec_msg_result, &olen,
dec_msg + dec_msglen, taglen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "cipher_auth_decrypt", ret );
if( ret == POLARSSL_ERR_CIPHER_AUTH_FAILED )
return( POLARSSL_ERR_SSL_INVALID_MAC );
return( ret );
}
auth_done++;
if( olen != dec_msglen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
}
else
#endif /* POLARSSL_GCM_C || POLARSSL_CCM_C */
#if defined(POLARSSL_CIPHER_MODE_CBC) && \
( defined(POLARSSL_AES_C) || defined(POLARSSL_CAMELLIA_C) )
if( mode == POLARSSL_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(POLARSSL_SSL_PROTO_TLS1_1) || defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= 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 )
{
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( POLARSSL_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(POLARSSL_SSL_ENCRYPT_THEN_MAC)
if( ssl->session_in->encrypt_then_mac == SSL_ETM_ENABLED )
{
unsigned char computed_mac[POLARSSL_SSL_MAX_MAC_SIZE];
unsigned char pseudo_hdr[13];
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 );
SSL_DEBUG_BUF( 4, "MAC'd meta-data", pseudo_hdr, 13 );
md_hmac_update( &ssl->transform_in->md_ctx_dec, pseudo_hdr, 13 );
md_hmac_update( &ssl->transform_in->md_ctx_dec,
ssl->in_iv, ssl->in_msglen );
md_hmac_finish( &ssl->transform_in->md_ctx_dec, computed_mac );
md_hmac_reset( &ssl->transform_in->md_ctx_dec );
SSL_DEBUG_BUF( 4, "message mac", ssl->in_iv + ssl->in_msglen,
ssl->transform_in->maclen );
SSL_DEBUG_BUF( 4, "computed mac", computed_mac,
ssl->transform_in->maclen );
if( safer_memcmp( ssl->in_iv + ssl->in_msglen, computed_mac,
ssl->transform_in->maclen ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "message mac does not match" ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
auth_done++;
}
#endif /* POLARSSL_SSL_ENCRYPT_THEN_MAC */
/*
* Check length sanity
*/
if( ssl->in_msglen % ssl->transform_in->ivlen != 0 )
{
SSL_DEBUG_MSG( 1, ( "msglen (%d) %% ivlen (%d) != 0",
ssl->in_msglen, ssl->transform_in->ivlen ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
#if defined(POLARSSL_SSL_PROTO_TLS1_1) || defined(POLARSSL_SSL_PROTO_TLS1_2)
/*
* Initialize for prepended IV for block cipher in TLS v1.1 and up
*/
if( ssl->minor_ver >= SSL_MINOR_VERSION_2 )
{
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 /* POLARSSL_SSL_PROTO_TLS1_1 || POLARSSL_SSL_PROTO_TLS1_2 */
if( ( ret = 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 )
{
SSL_DEBUG_RET( 1, "cipher_crypt", ret );
return( ret );
}
if( dec_msglen != olen )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1)
if( ssl->minor_ver < 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(POLARSSL_SSL_DEBUG_ALL)
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(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
if( padlen > ssl->transform_in->ivlen )
{
#if defined(POLARSSL_SSL_DEBUG_ALL)
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 /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver > 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 - 1;
/*
* Padding is guaranteed to be incorrect if:
* 1. padlen >= ssl->in_msglen
*
* 2. padding_idx >= SSL_MAX_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 &= ( ssl->in_msglen >= padlen + 1 );
correct &= ( padding_idx < SSL_MAX_CONTENT_LEN +
ssl->transform_in->maclen );
padding_idx *= correct;
for( i = 1; 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(POLARSSL_SSL_DEBUG_ALL)
if( padlen > 0 && correct == 0 )
SSL_DEBUG_MSG( 1, ( "bad padding byte detected" ) );
#endif
padlen &= correct * 0x1FF;
}
else
#endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 || \
POLARSSL_SSL_PROTO_TLS1_2 */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
ssl->in_msglen -= padlen;
}
else
#endif /* POLARSSL_CIPHER_MODE_CBC &&
( POLARSSL_AES_C || POLARSSL_CAMELLIA_C ) */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
SSL_DEBUG_BUF( 4, "raw buffer after decryption",
ssl->in_msg, ssl->in_msglen );
/*
* Authenticate if not done yet.
* Compute the MAC regardless of the padding result (RFC4346, CBCTIME).
*/
#if defined(POLARSSL_SOME_MODES_USE_MAC)
if( auth_done == 0 )
{
unsigned char tmp[POLARSSL_SSL_MAX_MAC_SIZE];
ssl->in_msglen -= ssl->transform_in->maclen;
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, ssl->transform_in->maclen );
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == 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 );
}
else
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
if( ssl->minor_ver > SSL_MINOR_VERSION_0 )
{
/*
* 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)
*/
size_t j, extra_run = 0;
extra_run = ( 13 + ssl->in_msglen + padlen + 8 ) / 64 -
( 13 + ssl->in_msglen + 8 ) / 64;
extra_run &= correct * 0xFF;
md_hmac_update( &ssl->transform_in->md_ctx_dec, ssl->in_ctr, 13 );
md_hmac_update( &ssl->transform_in->md_ctx_dec, ssl->in_msg,
ssl->in_msglen );
md_hmac_finish( &ssl->transform_in->md_ctx_dec,
ssl->in_msg + ssl->in_msglen );
for( j = 0; j < extra_run; j++ )
md_process( &ssl->transform_in->md_ctx_dec, ssl->in_msg );
md_hmac_reset( &ssl->transform_in->md_ctx_dec );
}
else
#endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 || \
POLARSSL_SSL_PROTO_TLS1_2 */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
SSL_DEBUG_BUF( 4, "message mac", tmp, ssl->transform_in->maclen );
SSL_DEBUG_BUF( 4, "computed mac", ssl->in_msg + ssl->in_msglen,
ssl->transform_in->maclen );
if( safer_memcmp( tmp, ssl->in_msg + ssl->in_msglen,
ssl->transform_in->maclen ) != 0 )
{
#if defined(POLARSSL_SSL_DEBUG_ALL)
SSL_DEBUG_MSG( 1, ( "message mac does not match" ) );
#endif
correct = 0;
}
auth_done++;
/*
* Finally check the correct flag
*/
if( correct == 0 )
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
#endif /* POLARSSL_SOME_MODES_USE_MAC */
/* Make extra sure authentication was performed, exactly once */
if( auth_done != 1 )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
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;
/* The loops goes to its end iff the counter is wrapping */
if( i == 0 )
{
SSL_DEBUG_MSG( 1, ( "incoming message counter would wrap" ) );
return( POLARSSL_ERR_SSL_COUNTER_WRAPPING );
}
SSL_DEBUG_MSG( 2, ( "<= decrypt buf" ) );
return( 0 );
}
#undef MAC_NONE
#undef MAC_PLAINTEXT
#undef MAC_CIPHERTEXT
#if defined(POLARSSL_ZLIB_SUPPORT)
/*
* Compression/decompression functions
*/
static int ssl_compress_buf( ssl_context *ssl )
{
int ret;
unsigned char *msg_post = ssl->out_msg;
size_t len_pre = ssl->out_msglen;
unsigned char *msg_pre = ssl->compress_buf;
SSL_DEBUG_MSG( 2, ( "=> compress buf" ) );
if( len_pre == 0 )
return( 0 );
memcpy( msg_pre, ssl->out_msg, len_pre );
SSL_DEBUG_MSG( 3, ( "before compression: msglen = %d, ",
ssl->out_msglen ) );
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 = SSL_BUFFER_LEN;
ret = deflate( &ssl->transform_out->ctx_deflate, Z_SYNC_FLUSH );
if( ret != Z_OK )
{
SSL_DEBUG_MSG( 1, ( "failed to perform compression (%d)", ret ) );
return( POLARSSL_ERR_SSL_COMPRESSION_FAILED );
}
ssl->out_msglen = SSL_BUFFER_LEN -
ssl->transform_out->ctx_deflate.avail_out;
SSL_DEBUG_MSG( 3, ( "after compression: msglen = %d, ",
ssl->out_msglen ) );
SSL_DEBUG_BUF( 4, "after compression: output payload",
ssl->out_msg, ssl->out_msglen );
SSL_DEBUG_MSG( 2, ( "<= compress buf" ) );
return( 0 );
}
static int ssl_decompress_buf( ssl_context *ssl )
{
int ret;
unsigned char *msg_post = ssl->in_msg;
size_t len_pre = ssl->in_msglen;
unsigned char *msg_pre = ssl->compress_buf;
SSL_DEBUG_MSG( 2, ( "=> decompress buf" ) );
if( len_pre == 0 )
return( 0 );
memcpy( msg_pre, ssl->in_msg, len_pre );
SSL_DEBUG_MSG( 3, ( "before decompression: msglen = %d, ",
ssl->in_msglen ) );
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 = SSL_MAX_CONTENT_LEN;
ret = inflate( &ssl->transform_in->ctx_inflate, Z_SYNC_FLUSH );
if( ret != Z_OK )
{
SSL_DEBUG_MSG( 1, ( "failed to perform decompression (%d)", ret ) );
return( POLARSSL_ERR_SSL_COMPRESSION_FAILED );
}
ssl->in_msglen = SSL_MAX_CONTENT_LEN -
ssl->transform_in->ctx_inflate.avail_out;
SSL_DEBUG_MSG( 3, ( "after decompression: msglen = %d, ",
ssl->in_msglen ) );
SSL_DEBUG_BUF( 4, "after decompression: input payload",
ssl->in_msg, ssl->in_msglen );
SSL_DEBUG_MSG( 2, ( "<= decompress buf" ) );
return( 0 );
}
#endif /* POLARSSL_ZLIB_SUPPORT */
/*
* 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" ) );
if( nb_want > SSL_BUFFER_LEN - 8 )
{
SSL_DEBUG_MSG( 1, ( "requesting more data than fits" ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
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, done = 0;
size_t len = ssl->out_msglen;
SSL_DEBUG_MSG( 2, ( "=> write record" ) );
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 ) );
if( ssl->out_msg[0] != SSL_HS_HELLO_REQUEST )
ssl->handshake->update_checksum( ssl, ssl->out_msg, len );
}
#if defined(POLARSSL_ZLIB_SUPPORT)
if( ssl->transform_out != NULL &&
ssl->session_out->compression == SSL_COMPRESS_DEFLATE )
{
if( ( ret = ssl_compress_buf( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_compress_buf", ret );
return( ret );
}
len = ssl->out_msglen;
}
#endif /*POLARSSL_ZLIB_SUPPORT */
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_write != NULL )
{
SSL_DEBUG_MSG( 2, ( "going for ssl_hw_record_write()" ) );
ret = ssl_hw_record_write( ssl );
if( ret != 0 && ret != POLARSSL_ERR_SSL_HW_ACCEL_FALLTHROUGH )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_write", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
if( ret == 0 )
done = 1;
}
#endif /* POLARSSL_SSL_HW_RECORD_ACCEL */
if( !done )
{
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->transform_out != NULL )
{
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, done = 0;
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 );
}
if( ssl->state != SSL_HANDSHAKE_OVER )
ssl->handshake->update_checksum( ssl, 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 );
}
/* Sanity check (outer boundaries) */
if( ssl->in_msglen < 1 || ssl->in_msglen > SSL_BUFFER_LEN - 13 )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/*
* Make sure the message length is acceptable for the current transform
* and protocol version.
*/
if( ssl->transform_in == NULL )
{
if( 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->transform_in->minlen )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 &&
ssl->in_msglen > ssl->transform_in->minlen + SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
/*
* TLS encrypted messages can have up to 256 bytes of padding
*/
if( ssl->minor_ver >= SSL_MINOR_VERSION_1 &&
ssl->in_msglen > ssl->transform_in->minlen +
SSL_MAX_CONTENT_LEN + 256 )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
#endif
}
/*
* 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 defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_read != NULL )
{
SSL_DEBUG_MSG( 2, ( "going for ssl_hw_record_read()" ) );
ret = ssl_hw_record_read( ssl );
if( ret != 0 && ret != POLARSSL_ERR_SSL_HW_ACCEL_FALLTHROUGH )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_read", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
if( ret == 0 )
done = 1;
}
#endif /* POLARSSL_SSL_HW_RECORD_ACCEL */
if( !done && ssl->transform_in != NULL )
{
if( ( ret = ssl_decrypt_buf( ssl ) ) != 0 )
{
#if defined(POLARSSL_SSL_ALERT_MESSAGES)
if( ret == POLARSSL_ERR_SSL_INVALID_MAC )
{
ssl_send_alert_message( ssl,
SSL_ALERT_LEVEL_FATAL,
SSL_ALERT_MSG_BAD_RECORD_MAC );
}
#endif
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 defined(POLARSSL_ZLIB_SUPPORT)
if( ssl->transform_in != NULL &&
ssl->session_in->compression == SSL_COMPRESS_DEFLATE )
{
if( ( ret = ssl_decompress_buf( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_decompress_buf", ret );
return( ret );
}
ssl->in_hdr[3] = (unsigned char)( ssl->in_msglen >> 8 );
ssl->in_hdr[4] = (unsigned char)( ssl->in_msglen );
}
#endif /* POLARSSL_ZLIB_SUPPORT */
if( ssl->in_msgtype != SSL_MSG_HANDSHAKE &&
ssl->in_msgtype != SSL_MSG_ALERT &&
ssl->in_msgtype != SSL_MSG_CHANGE_CIPHER_SPEC &&
ssl->in_msgtype != SSL_MSG_APPLICATION_DATA )
{
SSL_DEBUG_MSG( 1, ( "unknown record type" ) );
if( ( ret = ssl_send_alert_message( ssl,
SSL_ALERT_LEVEL_FATAL,
SSL_ALERT_MSG_UNEXPECTED_MESSAGE ) ) != 0 )
{
return( ret );
}
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 );
}
if( ssl->state != SSL_HANDSHAKE_OVER )
ssl->handshake->update_checksum( ssl, 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 (msg %d)",
ssl->in_msg[1] ) );
return( POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE );
}
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 );
}
int ssl_send_fatal_handshake_failure( ssl_context *ssl )
{
int ret;
if( ( ret = ssl_send_alert_message( ssl,
SSL_ALERT_LEVEL_FATAL,
SSL_ALERT_MSG_HANDSHAKE_FAILURE ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int ssl_send_alert_message( ssl_context *ssl,
unsigned char level,
unsigned char message )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> send alert message" ) );
ssl->out_msgtype = SSL_MSG_ALERT;
ssl->out_msglen = 2;
ssl->out_msg[0] = level;
ssl->out_msg[1] = message;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= send alert message" ) );
return( 0 );
}
/*
* Handshake functions
*/
#if !defined(POLARSSL_KEY_EXCHANGE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED) && \
!defined(POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
int ssl_write_certificate( ssl_context *ssl )
{
const ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
int ssl_parse_certificate( ssl_context *ssl )
{
const ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
#else
int ssl_write_certificate( ssl_context *ssl )
{
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
size_t i, n;
const x509_crt *crt;
const ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
SSL_DEBUG_MSG( 2, ( "=> write certificate" ) );
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
{
if( ssl->client_auth == 0 )
{
SSL_DEBUG_MSG( 2, ( "<= skip write certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(POLARSSL_SSL_PROTO_SSL3)
/*
* If using SSLv3 and got no cert, send an Alert message
* (otherwise an empty Certificate message will be sent).
*/
if( ssl_own_cert( ssl ) == 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;
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
}
#endif /* POLARSSL_SSL_CLI_C */
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
{
if( ssl_own_cert( ssl ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "got no certificate to send" ) );
return( POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED );
}
}
#endif
SSL_DEBUG_CRT( 3, "own certificate", 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 = ssl_own_cert( ssl );
while( crt != NULL )
{
n = crt->raw.len;
if( n > SSL_MAX_CONTENT_LEN - 3 - i )
{
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;
#if defined(POLARSSL_SSL_PROTO_SSL3)
write_msg:
#endif
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( ret );
}
int ssl_parse_certificate( ssl_context *ssl )
{
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
size_t i, n;
const ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
SSL_DEBUG_MSG( 2, ( "=> parse certificate" ) );
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_PSK )
{
SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER &&
( ssl->authmode == SSL_VERIFY_NONE ||
ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_RSA_PSK ) )
{
ssl->session_negotiate->verify_result = BADCERT_SKIP_VERIFY;
SSL_DEBUG_MSG( 2, ( "<= skip parse certificate" ) );
ssl->state++;
return( 0 );
}
#endif
if( ( ret = ssl_read_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_read_record", ret );
return( ret );
}
ssl->state++;
#if defined(POLARSSL_SSL_SRV_C)
#if defined(POLARSSL_SSL_PROTO_SSL3)
/*
* 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->session_negotiate->verify_result = BADCERT_MISSING;
if( ssl->authmode == SSL_VERIFY_OPTIONAL )
return( 0 );
else
return( POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE );
}
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1) || \
defined(POLARSSL_SSL_PROTO_TLS1_2)
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->session_negotiate->verify_result = BADCERT_MISSING;
if( ssl->authmode == SSL_VERIFY_REQUIRED )
return( POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE );
else
return( 0 );
}
}
#endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 || \
POLARSSL_SSL_PROTO_TLS1_2 */
#endif /* POLARSSL_SSL_SRV_C */
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 );
}
/* In case we tried to reuse a session but it failed */
if( ssl->session_negotiate->peer_cert != NULL )
{
x509_crt_free( ssl->session_negotiate->peer_cert );
polarssl_free( ssl->session_negotiate->peer_cert );
}
if( ( ssl->session_negotiate->peer_cert = (x509_crt *) polarssl_malloc(
sizeof( x509_crt ) ) ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed",
sizeof( x509_crt ) ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
x509_crt_init( ssl->session_negotiate->peer_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 = x509_crt_parse_der( ssl->session_negotiate->peer_cert,
ssl->in_msg + i, n );
if( ret != 0 )
{
SSL_DEBUG_RET( 1, " x509_crt_parse_der", ret );
return( ret );
}
i += n;
}
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(POLARSSL_SSL_RENEGOTIATION) && defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT &&
ssl->renegotiation == SSL_RENEGOTIATION )
{
if( ssl->session->peer_cert == NULL )
{
SSL_DEBUG_MSG( 1, ( "new server cert during renegotiation" ) );
return( POLARSSL_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 )
{
SSL_DEBUG_MSG( 1, ( "server cert changed during renegotiation" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
}
#endif /* POLARSSL_SSL_RENEGOTIATION && POLARSSL_SSL_CLI_C */
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 );
}
/*
* Main check: verify certificate
*/
ret = x509_crt_verify( ssl->session_negotiate->peer_cert,
ssl->ca_chain, ssl->ca_crl, ssl->peer_cn,
&ssl->session_negotiate->verify_result,
ssl->f_vrfy, ssl->p_vrfy );
if( ret != 0 )
{
SSL_DEBUG_RET( 1, "x509_verify_cert", ret );
}
/*
* Secondary checks: always done, but change 'ret' only if it was 0
*/
#if defined(POLARSSL_SSL_SET_CURVES)
{
pk_context *pk = &ssl->session_negotiate->peer_cert->pk;
/* If certificate uses an EC key, make sure the curve is OK */
if( pk_can_do( pk, POLARSSL_PK_ECKEY ) &&
! ssl_curve_is_acceptable( ssl, pk_ec( *pk )->grp.id ) )
{
SSL_DEBUG_MSG( 1, ( "bad certificate (EC key curve)" ) );
if( ret == 0 )
ret = POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE;
}
}
#endif /* POLARSSL_SSL_SET_CURVES */
if( ssl_check_cert_usage( ssl->session_negotiate->peer_cert,
ciphersuite_info,
! ssl->endpoint ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad certificate (usage extensions)" ) );
if( ret == 0 )
ret = POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE;
}
if( ssl->authmode != SSL_VERIFY_REQUIRED )
ret = 0;
}
SSL_DEBUG_MSG( 2, ( "<= parse certificate" ) );
return( ret );
}
#endif /* !POLARSSL_KEY_EXCHANGE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED
!POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDH_RSA_ENABLED
!POLARSSL_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
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->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" ) );
if<