mbedtls/library/ssl_tls.c
2015-03-20 18:21:12 +00:00

6856 lines
200 KiB
C

/*
* SSLv3/TLSv1 shared functions
*
* Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
*
* This file is part of mbed TLS (https://tls.mbed.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 "mbedtls/config.h"
#else
#include POLARSSL_CONFIG_FILE
#endif
#if defined(POLARSSL_SSL_TLS_C)
#include "mbedtls/debug.h"
#include "mbedtls/ssl.h"
#include <string.h>
#if defined(POLARSSL_X509_CRT_PARSE_C) && \
defined(POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE)
#include "mbedtls/oid.h"
#endif
#if defined(POLARSSL_PLATFORM_C)
#include "mbedtls/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;
}
/* Length of the "epoch" field in the record header */
static inline size_t ssl_ep_len( const ssl_context *ssl )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
return( 2 );
#else
((void) ssl);
#endif
return( 0 );
}
#if defined(POLARSSL_SSL_PROTO_DTLS)
/*
* Start a timer.
* Passing millisecs = 0 cancels a running timer.
* The timer is already running iff time_limit != 0.
*/
static void ssl_set_timer( ssl_context *ssl, uint32_t millisecs )
{
ssl->time_limit = millisecs;
get_timer( &ssl->time_info, 1 );
}
/*
* Return -1 is timer is expired, 0 if it isn't.
*/
static int ssl_check_timer( ssl_context *ssl )
{
if( ssl->time_limit != 0 &&
get_timer( &ssl->time_info, 0 ) > ssl->time_limit )
{
return( -1 );
}
return( 0 );
}
/*
* Double the retransmit timeout value, within the allowed range,
* returning -1 if the maximum value has already been reached.
*/
static int ssl_double_retransmit_timeout( ssl_context *ssl )
{
uint32_t new_timeout;
if( ssl->handshake->retransmit_timeout >= ssl->hs_timeout_max )
return( -1 );
new_timeout = 2 * ssl->handshake->retransmit_timeout;
/* Avoid arithmetic overflow and range overflow */
if( new_timeout < ssl->handshake->retransmit_timeout ||
new_timeout > ssl->hs_timeout_max )
{
new_timeout = ssl->hs_timeout_max;
}
ssl->handshake->retransmit_timeout = new_timeout;
SSL_DEBUG_MSG( 3, ( "update timeout value to %d millisecs",
ssl->handshake->retransmit_timeout ) );
return( 0 );
}
static void ssl_reset_retransmit_timeout( ssl_context *ssl )
{
ssl->handshake->retransmit_timeout = ssl->hs_timeout_min;
SSL_DEBUG_MSG( 3, ( "update timeout value to %d millisecs",
ssl->handshake->retransmit_timeout ) );
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
#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 = 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 = 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 )
{
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, 8 );
md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_hdr, 3 );
md_hmac_update( &ssl->transform_out->md_ctx_enc, ssl->out_len, 2 );
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;
ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->transport, add_data + 9 );
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, i;
padlen = ssl->transform_out->ivlen - ( ssl->out_msglen + 1 ) %
ssl->transform_out->ivlen;
if( padlen == ssl->transform_out->ivlen )
padlen = 0;
for( i = 0; i <= padlen; i++ )
ssl->out_msg[ssl->out_msglen + i] = (unsigned char) padlen;
ssl->out_msglen += padlen + 1;
enc_msglen = ssl->out_msglen;
enc_msg = ssl->out_msg;
#if defined(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 );
}
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 < (size_t) 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;
ssl_write_version( ssl->major_ver, ssl->minor_ver,
ssl->transport, add_data + 9 );
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_len[0] = (unsigned char)( ssl->in_msglen >> 8 );
ssl->in_len[1] = (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, 8 );
md_hmac_update( &ssl->transform_in->md_ctx_dec, ssl->in_hdr, 3 );
md_hmac_update( &ssl->transform_in->md_ctx_dec, ssl->in_len, 2 );
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;
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
; /* in_ctr read from peer, not maintained internally */
}
else
#endif
{
for( i = 8; i > ssl_ep_len( ssl ); i-- )
if( ++ssl->in_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == ssl_ep_len( ssl ) )
{
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 */
#if defined(POLARSSL_SSL_SRV_C) && defined(POLARSSL_SSL_RENEGOTIATION)
static int ssl_write_hello_request( ssl_context *ssl );
#if defined(POLARSSL_SSL_PROTO_DTLS)
static int ssl_resend_hello_request( ssl_context *ssl )
{
/* If renegotiation is not enforced, retransmit until we would reach max
* timeout if we were using the usual handshake doubling scheme */
if( ssl->renego_max_records < 0 )
{
uint32_t ratio = ssl->hs_timeout_max / ssl->hs_timeout_min + 1;
unsigned char doublings = 1;
while( ratio != 0 )
{
++doublings;
ratio >>= 1;
}
if( ++ssl->renego_records_seen > doublings )
{
SSL_DEBUG_MSG( 0, ( "no longer retransmitting hello request" ) );
return( 0 );
}
}
return( ssl_write_hello_request( ssl ) );
}
#endif
#endif /* POLARSSL_SSL_SRV_C && POLARSSL_SSL_RENEGOTIATION */
/*
* Fill the input message buffer by appending data to it.
* The amount of data already fetched is in ssl->in_left.
*
* If we return 0, is it guaranteed that (at least) nb_want bytes are
* available (from this read and/or a previous one). Otherwise, an error code
* is returned (possibly EOF or WANT_READ).
*
* With stream transport (TLS) on success ssl->in_left == nb_want, but
* with datagram transport (DTLS) on success ssl->in_left >= nb_want,
* since we always read a whole datagram at once.
*
* For DTLS, it is up to the caller to set ssl->next_record_offset when
* they're done reading a record.
*/
int ssl_fetch_input( ssl_context *ssl, size_t nb_want )
{
int ret;
size_t len;
SSL_DEBUG_MSG( 2, ( "=> fetch input" ) );
if( ssl->f_recv == NULL && ssl->f_recv_timeout == NULL )
{
SSL_DEBUG_MSG( 1, ( "Bad usage of ssl_set_bio() "
"or ssl_set_bio_timeout()" ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
if( nb_want > SSL_BUFFER_LEN - (size_t)( ssl->in_hdr - ssl->in_buf ) )
{
SSL_DEBUG_MSG( 1, ( "requesting more data than fits" ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
uint32_t timeout;
/*
* The point is, we need to always read a full datagram at once, so we
* sometimes read more then requested, and handle the additional data.
* It could be the rest of the current record (while fetching the
* header) and/or some other records in the same datagram.
*/
/*
* Move to the next record in the already read datagram if applicable
*/
if( ssl->next_record_offset != 0 )
{
if( ssl->in_left < ssl->next_record_offset )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
ssl->in_left -= ssl->next_record_offset;
if( ssl->in_left != 0 )
{
SSL_DEBUG_MSG( 2, ( "next record in same datagram, offset: %d",
ssl->next_record_offset ) );
memmove( ssl->in_hdr,
ssl->in_hdr + ssl->next_record_offset,
ssl->in_left );
}
ssl->next_record_offset = 0;
}
SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
/*
* Done if we already have enough data.
*/
if( nb_want <= ssl->in_left)
{
SSL_DEBUG_MSG( 2, ( "<= fetch input" ) );
return( 0 );
}
/*
* A record can't be split accross datagrams. If we need to read but
* are not at the beginning of a new record, the caller did something
* wrong.
*/
if( ssl->in_left != 0 )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
SSL_DEBUG_MSG( 3, ( "current timer: %u", ssl->time_limit ) );
/*
* Don't even try to read if time's out already.
* This avoids by-passing the timer when repeatedly receiving messages
* that will end up being dropped.
*/
if( ssl_check_timer( ssl ) != 0 )
ret = POLARSSL_ERR_NET_TIMEOUT;
else
{
len = SSL_BUFFER_LEN - ( ssl->in_hdr - ssl->in_buf );
if( ssl->state != SSL_HANDSHAKE_OVER )
timeout = ssl->handshake->retransmit_timeout;
else
timeout = ssl->read_timeout;
SSL_DEBUG_MSG( 3, ( "f_recv_timeout: %u ms", timeout ) );
if( ssl->f_recv_timeout != NULL && timeout != 0 )
ret = ssl->f_recv_timeout( ssl->p_bio, ssl->in_hdr, len,
timeout );
else
ret = ssl->f_recv( ssl->p_bio, ssl->in_hdr, len );
SSL_DEBUG_RET( 2, "ssl->f_recv(_timeout)", ret );
if( ret == 0 )
return( POLARSSL_ERR_SSL_CONN_EOF );
}
if( ret == POLARSSL_ERR_NET_TIMEOUT )
{
SSL_DEBUG_MSG( 2, ( "timeout" ) );
ssl_set_timer( ssl, 0 );
if( ssl->state != SSL_HANDSHAKE_OVER )
{
if( ssl_double_retransmit_timeout( ssl ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "handshake timeout" ) );
return( POLARSSL_ERR_NET_TIMEOUT );
}
if( ( ret = ssl_resend( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_resend", ret );
return( ret );
}
return( POLARSSL_ERR_NET_WANT_READ );
}
#if defined(POLARSSL_SSL_SRV_C) && defined(POLARSSL_SSL_RENEGOTIATION)
else if( ssl->endpoint == SSL_IS_SERVER &&
ssl->renego_status == SSL_RENEGOTIATION_PENDING )
{
if( ( ret = ssl_resend_hello_request( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_resend_hello_request", ret );
return( ret );
}
return( POLARSSL_ERR_NET_WANT_READ );
}
#endif /* POLARSSL_SSL_SRV_C && POLARSSL_SSL_RENEGOTIATION */
}
if( ret < 0 )
return( ret );
ssl->in_left = ret;
}
else
#endif
{
SSL_DEBUG_MSG( 2, ( "in_left: %d, nb_want: %d",
ssl->in_left, nb_want ) );
while( ssl->in_left < nb_want )
{
len = nb_want - ssl->in_left;
ret = ssl->f_recv( ssl->p_bio, 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, i;
SSL_DEBUG_MSG( 2, ( "=> flush output" ) );
if( ssl->f_send == NULL )
{
SSL_DEBUG_MSG( 1, ( "Bad usage of ssl_set_bio() "
"or ssl_set_bio_timeout()" ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
/* Avoid incrementing counter if data is flushed */
if( ssl->out_left == 0 )
{
SSL_DEBUG_MSG( 2, ( "<= flush output" ) );
return( 0 );
}
while( ssl->out_left > 0 )
{
SSL_DEBUG_MSG( 2, ( "message length: %d, out_left: %d",
ssl_hdr_len( ssl ) + ssl->out_msglen, ssl->out_left ) );
buf = ssl->out_hdr + ssl_hdr_len( ssl ) +
ssl->out_msglen - ssl->out_left;
ret = ssl->f_send( ssl->p_bio, buf, ssl->out_left );
SSL_DEBUG_RET( 2, "ssl->f_send", ret );
if( ret <= 0 )
return( ret );
ssl->out_left -= ret;
}
for( i = 8; i > ssl_ep_len( ssl ); i-- )
if( ++ssl->out_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == ssl_ep_len( ssl ) )
{
SSL_DEBUG_MSG( 1, ( "outgoing message counter would wrap" ) );
return( POLARSSL_ERR_SSL_COUNTER_WRAPPING );
}
SSL_DEBUG_MSG( 2, ( "<= flush output" ) );
return( 0 );
}
/*
* Functions to handle the DTLS retransmission state machine
*/
#if defined(POLARSSL_SSL_PROTO_DTLS)
/*
* Append current handshake message to current outgoing flight
*/
static int ssl_flight_append( ssl_context *ssl )
{
ssl_flight_item *msg;
/* Allocate space for current message */
if( ( msg = polarssl_malloc( sizeof( ssl_flight_item ) ) ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc %d bytes failed",
sizeof( ssl_flight_item ) ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
if( ( msg->p = polarssl_malloc( ssl->out_msglen ) ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc %d bytes failed", ssl->out_msglen ) );
polarssl_free( msg );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
/* Copy current handshake message with headers */
memcpy( msg->p, ssl->out_msg, ssl->out_msglen );
msg->len = ssl->out_msglen;
msg->type = ssl->out_msgtype;
msg->next = NULL;
/* Append to the current flight */
if( ssl->handshake->flight == NULL )
ssl->handshake->flight = msg;
else
{
ssl_flight_item *cur = ssl->handshake->flight;
while( cur->next != NULL )
cur = cur->next;
cur->next = msg;
}
return( 0 );
}
/*
* Free the current flight of handshake messages
*/
static void ssl_flight_free( ssl_flight_item *flight )
{
ssl_flight_item *cur = flight;
ssl_flight_item *next;
while( cur != NULL )
{
next = cur->next;
polarssl_free( cur->p );
polarssl_free( cur );
cur = next;
}
}
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
static void ssl_dtls_replay_reset( ssl_context *ssl );
#endif
/*
* Swap transform_out and out_ctr with the alternative ones
*/
static void ssl_swap_epochs( ssl_context *ssl )
{
ssl_transform *tmp_transform;
unsigned char tmp_out_ctr[8];
if( ssl->transform_out == ssl->handshake->alt_transform_out )
{
SSL_DEBUG_MSG( 3, ( "skip swap epochs" ) );
return;
}
SSL_DEBUG_MSG( 3, ( "swap epochs" ) );
/* Swap transforms */
tmp_transform = ssl->transform_out;
ssl->transform_out = ssl->handshake->alt_transform_out;
ssl->handshake->alt_transform_out = tmp_transform;
/* Swap epoch + sequence_number */
memcpy( tmp_out_ctr, ssl->out_ctr, 8 );
memcpy( ssl->out_ctr, ssl->handshake->alt_out_ctr, 8 );
memcpy( ssl->handshake->alt_out_ctr, tmp_out_ctr, 8 );
/* Adjust to the newly activated transform */
if( ssl->transform_out != NULL &&
ssl->minor_ver >= SSL_MINOR_VERSION_2 )
{
ssl->out_msg = ssl->out_iv + ssl->transform_out->ivlen -
ssl->transform_out->fixed_ivlen;
}
else
ssl->out_msg = ssl->out_iv;
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_activate != NULL )
{
if( ( ret = ssl_hw_record_activate( ssl, SSL_CHANNEL_OUTBOUND ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_activate", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
}
/*
* Retransmit the current flight of messages.
*
* Need to remember the current message in case flush_output returns
* WANT_WRITE, causing us to exit this function and come back later.
* This function must be called until state is no longer SENDING.
*/
int ssl_resend( ssl_context *ssl )
{
SSL_DEBUG_MSG( 2, ( "=> ssl_resend" ) );
if( ssl->handshake->retransmit_state != SSL_RETRANS_SENDING )
{
SSL_DEBUG_MSG( 2, ( "initialise resending" ) );
ssl->handshake->cur_msg = ssl->handshake->flight;
ssl_swap_epochs( ssl );
ssl->handshake->retransmit_state = SSL_RETRANS_SENDING;
}
while( ssl->handshake->cur_msg != NULL )
{
int ret;
ssl_flight_item *cur = ssl->handshake->cur_msg;
/* Swap epochs before sending Finished: we can't do it after
* sending ChangeCipherSpec, in case write returns WANT_READ.
* Must be done before copying, may change out_msg pointer */
if( cur->type == SSL_MSG_HANDSHAKE &&
cur->p[0] == SSL_HS_FINISHED )
{
ssl_swap_epochs( ssl );
}
memcpy( ssl->out_msg, cur->p, cur->len );
ssl->out_msglen = cur->len;
ssl->out_msgtype = cur->type;
ssl->handshake->cur_msg = cur->next;
SSL_DEBUG_BUF( 3, "resent handshake message header", ssl->out_msg, 12 );
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
}
if( ssl->state == SSL_HANDSHAKE_OVER )
ssl->handshake->retransmit_state = SSL_RETRANS_FINISHED;
else
{
ssl->handshake->retransmit_state = SSL_RETRANS_WAITING;
ssl_set_timer( ssl, ssl->handshake->retransmit_timeout );
}
SSL_DEBUG_MSG( 2, ( "<= ssl_resend" ) );
return( 0 );
}
/*
* To be called when the last message of an incoming flight is received.
*/
void ssl_recv_flight_completed( ssl_context *ssl )
{
/* We won't need to resend that one any more */
ssl_flight_free( ssl->handshake->flight );
ssl->handshake->flight = NULL;
ssl->handshake->cur_msg = NULL;
/* The next incoming flight will start with this msg_seq */
ssl->handshake->in_flight_start_seq = ssl->handshake->in_msg_seq;
/* Cancel timer */
ssl_set_timer( ssl, 0 );
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == SSL_HS_FINISHED )
{
ssl->handshake->retransmit_state = SSL_RETRANS_FINISHED;
}
else
ssl->handshake->retransmit_state = SSL_RETRANS_PREPARING;
}
/*
* To be called when the last message of an outgoing flight is send.
*/
void ssl_send_flight_completed( ssl_context *ssl )
{
ssl_reset_retransmit_timeout( ssl );
ssl_set_timer( ssl, ssl->handshake->retransmit_timeout );
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == SSL_HS_FINISHED )
{
ssl->handshake->retransmit_state = SSL_RETRANS_FINISHED;
}
else
ssl->handshake->retransmit_state = SSL_RETRANS_WAITING;
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
/*
* Record layer functions
*/
/*
* Write current record.
* Uses ssl->out_msgtype, ssl->out_msglen and bytes at ssl->out_msg.
*/
int ssl_write_record( ssl_context *ssl )
{
int ret, done = 0;
size_t len = ssl->out_msglen;
SSL_DEBUG_MSG( 2, ( "=> write record" ) );
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL &&
ssl->handshake->retransmit_state == SSL_RETRANS_SENDING )
{
; /* Skip special handshake treatment when resending */
}
else
#endif
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 ) );
/*
* DTLS has additional fields in the Handshake layer,
* between the length field and the actual payload:
* uint16 message_seq;
* uint24 fragment_offset;
* uint24 fragment_length;
*/
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
/* Make room for the additional DTLS fields */
memmove( ssl->out_msg + 12, ssl->out_msg + 4, len - 4 );
ssl->out_msglen += 8;
len += 8;
/* Write message_seq and update it, except for HelloRequest */
if( ssl->out_msg[0] != SSL_HS_HELLO_REQUEST )
{
ssl->out_msg[4] = ( ssl->handshake->out_msg_seq >> 8 ) & 0xFF;
ssl->out_msg[5] = ( ssl->handshake->out_msg_seq ) & 0xFF;
++( ssl->handshake->out_msg_seq );
}
else
{
ssl->out_msg[4] = 0;
ssl->out_msg[5] = 0;
}
/* We don't fragment, so frag_offset = 0 and frag_len = len */
memset( ssl->out_msg + 6, 0x00, 3 );
memcpy( ssl->out_msg + 9, ssl->out_msg + 1, 3 );
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
if( ssl->out_msg[0] != SSL_HS_HELLO_REQUEST )
ssl->handshake->update_checksum( ssl, ssl->out_msg, len );
}
/* Save handshake and CCS messages for resending */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL &&
ssl->handshake->retransmit_state != SSL_RETRANS_SENDING &&
( ssl->out_msgtype == SSL_MSG_CHANGE_CIPHER_SPEC ||
ssl->out_msgtype == SSL_MSG_HANDSHAKE ) )
{
if( ( ret = ssl_flight_append( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_flight_append", ret );
return( ret );
}
}
#endif
#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_write_version( ssl->major_ver, ssl->minor_ver,
ssl->transport, ssl->out_hdr + 1 );
ssl->out_len[0] = (unsigned char)( len >> 8 );
ssl->out_len[1] = (unsigned char)( len );
if( ssl->transform_out != NULL )
{
if( ( ret = ssl_encrypt_buf( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_encrypt_buf", ret );
return( ret );
}
len = ssl->out_msglen;
ssl->out_len[0] = (unsigned char)( len >> 8 );
ssl->out_len[1] = (unsigned char)( len );
}
ssl->out_left = ssl_hdr_len( ssl ) + 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_len[0] << 8 ) | ssl->out_len[1] ) );
SSL_DEBUG_BUF( 4, "output record sent to network",
ssl->out_hdr, ssl_hdr_len( ssl ) + 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 );
}
#if defined(POLARSSL_SSL_PROTO_DTLS)
/*
* Mark bits in bitmask (used for DTLS HS reassembly)
*/
static void ssl_bitmask_set( unsigned char *mask, size_t offset, size_t len )
{
unsigned int start_bits, end_bits;
start_bits = 8 - ( offset % 8 );
if( start_bits != 8 )
{
size_t first_byte_idx = offset / 8;
/* Special case */
if( len <= start_bits )
{
for( ; len != 0; len-- )
mask[first_byte_idx] |= 1 << ( start_bits - len );
/* Avoid potential issues with offset or len becoming invalid */
return;
}
offset += start_bits; /* Now offset % 8 == 0 */
len -= start_bits;
for( ; start_bits != 0; start_bits-- )
mask[first_byte_idx] |= 1 << ( start_bits - 1 );
}
end_bits = len % 8;
if( end_bits != 0 )
{
size_t last_byte_idx = ( offset + len ) / 8;
len -= end_bits; /* Now len % 8 == 0 */
for( ; end_bits != 0; end_bits-- )
mask[last_byte_idx] |= 1 << ( 8 - end_bits );
}
memset( mask + offset / 8, 0xFF, len / 8 );
}
/*
* Check that bitmask is full
*/
static int ssl_bitmask_check( unsigned char *mask, size_t len )
{
size_t i;
for( i = 0; i < len / 8; i++ )
if( mask[i] != 0xFF )
return( -1 );
for( i = 0; i < len % 8; i++ )
if( ( mask[len / 8] & ( 1 << ( 7 - i ) ) ) == 0 )
return( -1 );
return( 0 );
}
/*
* Reassemble fragmented DTLS handshake messages.
*
* Use a temporary buffer for reassembly, divided in two parts:
* - the first holds the reassembled message (including handshake header),
* - the second holds a bitmask indicating which parts of the message
* (excluding headers) have been received so far.
*/
static int ssl_reassemble_dtls_handshake( ssl_context *ssl )
{
unsigned char *msg, *bitmask;
size_t frag_len, frag_off;
size_t msg_len = ssl->in_hslen - 12; /* Without headers */
if( ssl->handshake == NULL )
{
SSL_DEBUG_MSG( 1, ( "not supported outside handshake (for now)" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
/*
* For first fragment, check size and allocate buffer
*/
if( ssl->handshake->hs_msg == NULL )
{
size_t alloc_len;
SSL_DEBUG_MSG( 2, ( "initialize reassembly, total length = %d",
msg_len ) );
if( ssl->in_hslen > SSL_MAX_CONTENT_LEN )
{
SSL_DEBUG_MSG( 1, ( "handshake message too large" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
/* The bitmask needs one bit per byte of message excluding header */
alloc_len = 12 + msg_len + msg_len / 8 + ( msg_len % 8 != 0 );
ssl->handshake->hs_msg = polarssl_malloc( alloc_len );
if( ssl->handshake->hs_msg == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc failed (%d bytes)", alloc_len ) );
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
memset( ssl->handshake->hs_msg, 0, alloc_len );
/* Prepare final header: copy msg_type, length and message_seq,
* then add standardised fragment_offset and fragment_length */
memcpy( ssl->handshake->hs_msg, ssl->in_msg, 6 );
memset( ssl->handshake->hs_msg + 6, 0, 3 );
memcpy( ssl->handshake->hs_msg + 9,
ssl->handshake->hs_msg + 1, 3 );
}
else
{
/* Make sure msg_type and length are consistent */
if( memcmp( ssl->handshake->hs_msg, ssl->in_msg, 4 ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "fragment header mismatch" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
}
msg = ssl->handshake->hs_msg + 12;
bitmask = msg + msg_len;
/*
* Check and copy current fragment
*/
frag_off = ( ssl->in_msg[6] << 16 ) |
( ssl->in_msg[7] << 8 ) |
ssl->in_msg[8];
frag_len = ( ssl->in_msg[9] << 16 ) |
( ssl->in_msg[10] << 8 ) |
ssl->in_msg[11];
if( frag_off + frag_len > msg_len )
{
SSL_DEBUG_MSG( 1, ( "invalid fragment offset/len: %d + %d > %d",
frag_off, frag_len, msg_len ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( frag_len + 12 > ssl->in_msglen )
{
SSL_DEBUG_MSG( 1, ( "invalid fragment length: %d + 12 > %d",
frag_len, ssl->in_msglen ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
SSL_DEBUG_MSG( 2, ( "adding fragment, offset = %d, length = %d",
frag_off, frag_len ) );
memcpy( msg + frag_off, ssl->in_msg + 12, frag_len );
ssl_bitmask_set( bitmask, frag_off, frag_len );
/*
* Do we have the complete message by now?
* If yes, finalize it, else ask to read the next record.
*/
if( ssl_bitmask_check( bitmask, msg_len ) != 0 )
{
SSL_DEBUG_MSG( 2, ( "message is not complete yet" ) );
return( POLARSSL_ERR_NET_WANT_READ );
}
SSL_DEBUG_MSG( 2, ( "handshake message completed" ) );
if( frag_len + 12 < ssl->in_msglen )
{
/*
* We'got more handshake messages in the same record.
* This case is not handled now because no know implementation does
* that and it's hard to test, so we prefer to fail cleanly for now.
*/
SSL_DEBUG_MSG( 1, ( "last fragment not alone in its record" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
if( ssl->in_left > ssl->next_record_offset )
{
/*
* We've got more data in the buffer after the current record,
* that we don't want to overwrite. Move it before writing the
* reassembled message, and adjust in_left and next_record_offset.
*/
unsigned char *cur_remain = ssl->in_hdr + ssl->next_record_offset;
unsigned char *new_remain = ssl->in_msg + ssl->in_hslen;
size_t remain_len = ssl->in_left - ssl->next_record_offset;
/* First compute and check new lengths */
ssl->next_record_offset = new_remain - ssl->in_hdr;
ssl->in_left = ssl->next_record_offset + remain_len;
if( ssl->in_left > SSL_BUFFER_LEN -
(size_t)( ssl->in_hdr - ssl->in_buf ) )
{
SSL_DEBUG_MSG( 1, ( "reassembled message too large for buffer" ) );
return( POLARSSL_ERR_SSL_BUFFER_TOO_SMALL );
}
memmove( new_remain, cur_remain, remain_len );
}
memcpy( ssl->in_msg, ssl->handshake->hs_msg, ssl->in_hslen );
polarssl_free( ssl->handshake->hs_msg );
ssl->handshake->hs_msg = NULL;
SSL_DEBUG_BUF( 3, "reassembled handshake message",
ssl->in_msg, ssl->in_hslen );
return( 0 );
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
static int ssl_prepare_handshake_record( ssl_context *ssl )
{
if( ssl->in_msglen < ssl_hs_hdr_len( ssl ) )
{
SSL_DEBUG_MSG( 1, ( "handshake message too short: %d",
ssl->in_msglen ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
ssl->in_hslen = ssl_hs_hdr_len( ssl ) + (
( ssl->in_msg[1] << 16 ) |
( 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 defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
int ret;
unsigned int recv_msg_seq = ( ssl->in_msg[4] << 8 ) | ssl->in_msg[5];
/* ssl->handshake is NULL when receiving ClientHello for renego */
if( ssl->handshake != NULL &&
recv_msg_seq != ssl->handshake->in_msg_seq )
{
/* Retransmit only on last message from previous flight, to avoid
* too many retransmissions.
* Besides, No sane server ever retransmits HelloVerifyRequest */
if( recv_msg_seq == ssl->handshake->in_flight_start_seq - 1 &&
ssl->in_msg[0] != SSL_HS_HELLO_VERIFY_REQUEST )
{
SSL_DEBUG_MSG( 2, ( "received message from last flight, "
"message_seq = %d, start_of_flight = %d",
recv_msg_seq,
ssl->handshake->in_flight_start_seq ) );
if( ( ret = ssl_resend( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_resend", ret );
return( ret );
}
}
else
{
SSL_DEBUG_MSG( 2, ( "dropping out-of-sequence message: "
"message_seq = %d, expected = %d",
recv_msg_seq,
ssl->handshake->in_msg_seq ) );
}
return( POLARSSL_ERR_NET_WANT_READ );
}
/* Wait until message completion to increment in_msg_seq */
/* Reassemble if current message is fragmented or reassembly is
* already in progress */
if( ssl->in_msglen < ssl->in_hslen ||
memcmp( ssl->in_msg + 6, "\0\0\0", 3 ) != 0 ||
memcmp( ssl->in_msg + 9, ssl->in_msg + 1, 3 ) != 0 ||
( ssl->handshake != NULL && ssl->handshake->hs_msg != NULL ) )
{
SSL_DEBUG_MSG( 2, ( "found fragmented DTLS handshake message" ) );
if( ( ret = ssl_reassemble_dtls_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_reassemble_dtls_handshake", ret );
return( ret );
}
}
}
else
#endif /* POLARSSL_SSL_PROTO_DTLS */
/* With TLS we don't handle fragmentation (for now) */
if( ssl->in_msglen < ssl->in_hslen )
{
SSL_DEBUG_MSG( 1, ( "TLS handshake fragmentation not supported" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
if( ssl->state != SSL_HANDSHAKE_OVER )
ssl->handshake->update_checksum( ssl, ssl->in_msg, ssl->in_hslen );
/* Handshake message is complete, increment counter */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL )
{
ssl->handshake->in_msg_seq++;
}
#endif
return( 0 );
}
/*
* DTLS anti-replay: RFC 6347 4.1.2.6
*
* in_window is a field of bits numbered from 0 (lsb) to 63 (msb).
* Bit n is set iff record number in_window_top - n has been seen.
*
* Usually, in_window_top is the last record number seen and the lsb of
* in_window is set. The only exception is the initial state (record number 0
* not seen yet).
*/
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
static void ssl_dtls_replay_reset( ssl_context *ssl )
{
ssl->in_window_top = 0;
ssl->in_window = 0;
}
static inline uint64_t ssl_load_six_bytes( unsigned char *buf )
{
return( ( (uint64_t) buf[0] << 40 ) |
( (uint64_t) buf[1] << 32 ) |
( (uint64_t) buf[2] << 24 ) |
( (uint64_t) buf[3] << 16 ) |
( (uint64_t) buf[4] << 8 ) |
( (uint64_t) buf[5] ) );
}
/*
* Return 0 if sequence number is acceptable, -1 otherwise
*/
int ssl_dtls_replay_check( ssl_context *ssl )
{
uint64_t rec_seqnum = ssl_load_six_bytes( ssl->in_ctr + 2 );
uint64_t bit;
if( ssl->anti_replay == SSL_ANTI_REPLAY_DISABLED )
return( 0 );
if( rec_seqnum > ssl->in_window_top )
return( 0 );
bit = ssl->in_window_top - rec_seqnum;
if( bit >= 64 )
return( -1 );
if( ( ssl->in_window & ( (uint64_t) 1 << bit ) ) != 0 )
return( -1 );
return( 0 );
}
/*
* Update replay window on new validated record
*/
void ssl_dtls_replay_update( ssl_context *ssl )
{
uint64_t rec_seqnum = ssl_load_six_bytes( ssl->in_ctr + 2 );
if( ssl->anti_replay == SSL_ANTI_REPLAY_DISABLED )
return;
if( rec_seqnum > ssl->in_window_top )
{
/* Update window_top and the contents of the window */
uint64_t shift = rec_seqnum - ssl->in_window_top;
if( shift >= 64 )
ssl->in_window = 1;
else
{
ssl->in_window <<= shift;
ssl->in_window |= 1;
}
ssl->in_window_top = rec_seqnum;
}
else
{
/* Mark that number as seen in the current window */
uint64_t bit = ssl->in_window_top - rec_seqnum;
if( bit < 64 ) /* Always true, but be extra sure */
ssl->in_window |= (uint64_t) 1 << bit;
}
}
#endif /* POLARSSL_SSL_DTLS_ANTI_REPLAY */
/*
* ContentType type;
* ProtocolVersion version;
* uint16 epoch; // DTLS only
* uint48 sequence_number; // DTLS only
* uint16 length;
*/
static int ssl_parse_record_header( ssl_context *ssl )
{
int ret;
int major_ver, minor_ver;
SSL_DEBUG_BUF( 4, "input record header", ssl->in_hdr, ssl_hdr_len( ssl ) );
ssl->in_msgtype = ssl->in_hdr[0];
ssl->in_msglen = ( ssl->in_len[0] << 8 ) | ssl->in_len[1];
ssl_read_version( &major_ver, &minor_ver, ssl->transport, ssl->in_hdr + 1 );
SSL_DEBUG_MSG( 3, ( "input record: msgtype = %d, "
"version = [%d:%d], msglen = %d",
ssl->in_msgtype,
major_ver, minor_ver, ssl->in_msglen ) );
/* Check record type */
if( ssl->in_msgtype != 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 defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
/* Drop unexpected ChangeCipherSpec messages */
if( ssl->in_msgtype == SSL_MSG_CHANGE_CIPHER_SPEC &&
ssl->state != SSL_CLIENT_CHANGE_CIPHER_SPEC &&
ssl->state != SSL_SERVER_CHANGE_CIPHER_SPEC )
{
SSL_DEBUG_MSG( 1, ( "dropping unexpected ChangeCipherSpec" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/* Drop unexpected ApplicationData records,
* except at the beginning of renegotiations */
if( ssl->in_msgtype == SSL_MSG_APPLICATION_DATA &&
ssl->state != SSL_HANDSHAKE_OVER
#if defined(POLARSSL_SSL_RENEGOTIATION)
&& ! ( ssl->renego_status == SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->state == SSL_SERVER_HELLO )
#endif
)
{
SSL_DEBUG_MSG( 1, ( "dropping unexpected ApplicationData" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
}
#endif
/* Check version */
if( major_ver != ssl->major_ver )
{
SSL_DEBUG_MSG( 1, ( "major version mismatch" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
if( minor_ver > ssl->max_minor_ver )
{
SSL_DEBUG_MSG( 1, ( "minor version mismatch" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/* Check epoch (and sequence number) with DTLS */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
unsigned int rec_epoch = ( ssl->in_ctr[0] << 8 ) | ssl->in_ctr[1];
if( rec_epoch != ssl->in_epoch )
{
SSL_DEBUG_MSG( 1, ( "record from another epoch: "
"expected %d, received %d",
ssl->in_epoch, rec_epoch ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
if( ssl_dtls_replay_check( ssl ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "replayed record" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
#endif
}
#endif /* POLARSSL_SSL_PROTO_DTLS */
/* Check length against the size of our buffer */
if( ssl->in_msglen > SSL_BUFFER_LEN
- (size_t)( ssl->in_msg - ssl->in_buf ) )
{
SSL_DEBUG_MSG( 1, ( "bad message length" ) );
return( POLARSSL_ERR_SSL_INVALID_RECORD );
}
/* Check length against bounds of the current transform and version */
if( ssl->transform_in == NULL )
{
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->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
}
return( 0 );
}
/*
* If applicable, decrypt (and decompress) record content
*/
static int ssl_prepare_record_content( ssl_context *ssl )
{
int ret, done = 0;
SSL_DEBUG_BUF( 4, "input record from network",
ssl->in_hdr, ssl_hdr_len( ssl ) + 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 )
{
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 );
}
// TODO: what's the purpose of these lines? is in_len used?
ssl->in_len[0] = (unsigned char)( ssl->in_msglen >> 8 );
ssl->in_len[1] = (unsigned char)( ssl->in_msglen );
}
#endif /* POLARSSL_ZLIB_SUPPORT */
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
ssl_dtls_replay_update( ssl );
}
#endif
return( 0 );
}
static void ssl_handshake_wrapup_free_hs_transform( ssl_context *ssl );
/*
* Read a record.
*
* For DTLS, silently ignore invalid records (RFC 4.1.2.7.)
* and continue reading until a valid record is found.
*/
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_DEBUG_BUF( 4, "remaining content in record",
ssl->in_msg, ssl->in_msglen );
if( ( ret = ssl_prepare_handshake_record( ssl ) ) != 0 )
return( ret );
return( 0 );
}
ssl->in_hslen = 0;
/*
* Read the record header and parse it
*/
#if defined(POLARSSL_SSL_PROTO_DTLS)
read_record_header:
#endif
if( ( ret = ssl_fetch_input( ssl, ssl_hdr_len( ssl ) ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
if( ( ret = ssl_parse_record_header( ssl ) ) != 0 )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
/* Ignore bad record and get next one; drop the whole datagram
* since current header cannot be trusted to find the next record
* in current datagram */
ssl->next_record_offset = 0;
ssl->in_left = 0;
SSL_DEBUG_MSG( 1, ( "discarding invalid record (header)" ) );
goto read_record_header;
}
#endif
return( ret );
}
/*
* Read and optionally decrypt the message contents
*/
if( ( ret = ssl_fetch_input( ssl,
ssl_hdr_len( ssl ) + ssl->in_msglen ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_fetch_input", ret );
return( ret );
}
/* Done reading this record, get ready for the next one */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
ssl->next_record_offset = ssl->in_msglen + ssl_hdr_len( ssl );
else
#endif
ssl->in_left = 0;
if( ( ret = ssl_prepare_record_content( ssl ) ) != 0 )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
/* Silently discard invalid records */
if( ret == POLARSSL_ERR_SSL_INVALID_RECORD ||
ret == POLARSSL_ERR_SSL_INVALID_MAC )
{
#if defined(POLARSSL_SSL_DTLS_BADMAC_LIMIT)
if( ssl->badmac_limit != 0 &&
++ssl->badmac_seen >= ssl->badmac_limit )
{
SSL_DEBUG_MSG( 1, ( "too many records with bad MAC" ) );
return( POLARSSL_ERR_SSL_INVALID_MAC );
}
#endif
SSL_DEBUG_MSG( 1, ( "discarding invalid record (mac)" ) );
goto read_record_header;
}
return( ret );
}
else
#endif
{
/* Error out (and send alert) on invalid records */
#if defined(POLARSSL_SSL_ALL_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
return( ret );
}
}
/*
* When we sent the last flight of the handshake, we MUST respond to a
* retransmit of the peer's previous flight with a retransmit. (In
* practice, only the Finished message will make it, other messages
* including CCS use the old transform so they're dropped as invalid.)
*
* If the record we received is not a handshake message, however, it
* means the peer received our last flight so we can clean up
* handshake info.
*
* This check needs to be done before prepare_handshake() due to an edge
* case: if the client immediately requests renegotiation, this
* finishes the current handshake first, avoiding the new ClientHello
* being mistaken for an ancient message in the current handshake.
*/
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->handshake != NULL &&
ssl->state == SSL_HANDSHAKE_OVER )
{
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == SSL_HS_FINISHED )
{
SSL_DEBUG_MSG( 2, ( "received retransmit of last flight" ) );
if( ( ret = ssl_resend( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_resend", ret );
return( ret );
}
return( POLARSSL_ERR_NET_WANT_READ );
}
else
{
ssl_handshake_wrapup_free_hs_transform( ssl );
}
}
#endif
/*
* Handle particular types of records
*/
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE )
{
if( ( ret = ssl_prepare_handshake_record( ssl ) ) != 0 )
return( ret );
}
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_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 == 3 + ssl_hs_hdr_len( ssl ) &&
ssl->in_msgtype == SSL_MSG_HANDSHAKE &&
ssl->in_msg[0] == SSL_HS_CERTIFICATE &&
memcmp( ssl->in_msg + ssl_hs_hdr_len( ssl ), "\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 < ssl_hs_hdr_len( ssl ) + 3 + 3 )
{
SSL_DEBUG_MSG( 1, ( "bad certificate message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE );
}
i = ssl_hs_hdr_len( ssl );
/*
* Same message structure as in ssl_write_certificate()
*/
n = ( ssl->in_msg[i+1] << 8 ) | ssl->in_msg[i+2];
if( ssl->in_msg[i] != 0 ||
ssl->in_hslen != n + 3 + ssl_hs_hdr_len( ssl ) )
{
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 = 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 += 3;
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->renego_status == SSL_RENEGOTIATION_IN_PROGRESS )
{
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)
{
const 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( ( 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 );
}
/*
* Switch to our negotiated transform and session parameters for inbound
* data.
*/
SSL_DEBUG_MSG( 3, ( "switching to new transform spec for inbound data" ) );
ssl->transform_in = ssl->transform_negotiate;
ssl->session_in = ssl->session_negotiate;
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
ssl_dtls_replay_reset( ssl );
#endif
/* Increment epoch */
if( ++ssl->in_epoch == 0 )
{
SSL_DEBUG_MSG( 1, ( "DTLS epoch would wrap" ) );
return( POLARSSL_ERR_SSL_COUNTER_WRAPPING );
}
}
else
#endif /* POLARSSL_SSL_PROTO_DTLS */
memset( ssl->in_ctr, 0, 8 );
/*
* Set the in_msg pointer to the correct location based on IV length
*/
if( ssl->minor_ver >= SSL_MINOR_VERSION_2 )
{
ssl->in_msg = ssl->in_iv + ssl->transform_negotiate->ivlen -
ssl->transform_negotiate->fixed_ivlen;
}
else
ssl->in_msg = ssl->in_iv;
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_activate != NULL )
{
if( ( ret = ssl_hw_record_activate( ssl, SSL_CHANNEL_INBOUND ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_activate", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
ssl->state++;
SSL_DEBUG_MSG( 2, ( "<= parse change cipher spec" ) );
return( 0 );
}
void ssl_optimize_checksum( ssl_context *ssl,
const ssl_ciphersuite_t *ciphersuite_info )
{
((void) ciphersuite_info);
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1) || \
defined(POLARSSL_SSL_PROTO_TLS1_1)
if( ssl->minor_ver < SSL_MINOR_VERSION_3 )
ssl->handshake->update_checksum = ssl_update_checksum_md5sha1;
else
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA512_C)
if( ciphersuite_info->mac == POLARSSL_MD_SHA384 )
ssl->handshake->update_checksum = ssl_update_checksum_sha384;
else
#endif
#if defined(POLARSSL_SHA256_C)
if( ciphersuite_info->mac != POLARSSL_MD_SHA384 )
ssl->handshake->update_checksum = ssl_update_checksum_sha256;
else
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return;
}
}
void ssl_reset_checksum( ssl_context *ssl )
{
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1) || \
defined(POLARSSL_SSL_PROTO_TLS1_1)
md5_starts( &ssl->handshake->fin_md5 );
sha1_starts( &ssl->handshake->fin_sha1 );
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
sha256_starts( &ssl->handshake->fin_sha256, 0 );
#endif
#if defined(POLARSSL_SHA512_C)
sha512_starts( &ssl->handshake->fin_sha512, 1 );
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
}
static void ssl_update_checksum_start( ssl_context *ssl,
const unsigned char *buf, size_t len )
{
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1) || \
defined(POLARSSL_SSL_PROTO_TLS1_1)
md5_update( &ssl->handshake->fin_md5 , buf, len );
sha1_update( &ssl->handshake->fin_sha1, buf, len );
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
sha256_update( &ssl->handshake->fin_sha256, buf, len );
#endif
#if defined(POLARSSL_SHA512_C)
sha512_update( &ssl->handshake->fin_sha512, buf, len );
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
}
#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 *ssl,
const unsigned char *buf, size_t len )
{
md5_update( &ssl->handshake->fin_md5 , buf, len );
sha1_update( &ssl->handshake->fin_sha1, buf, len );
}
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
static void ssl_update_checksum_sha256( ssl_context *ssl,
const unsigned char *buf, size_t len )
{
sha256_update( &ssl->handshake->fin_sha256, buf, len );
}
#endif
#if defined(POLARSSL_SHA512_C)
static void ssl_update_checksum_sha384( ssl_context *ssl,
const unsigned char *buf, size_t len )
{
sha512_update( &ssl->handshake->fin_sha512, buf, len );
}
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
#if defined(POLARSSL_SSL_PROTO_SSL3)
static void ssl_calc_finished_ssl(
ssl_context *ssl, unsigned char *buf, int from )
{
const char *sender;
md5_context md5;
sha1_context sha1;
unsigned char padbuf[48];
unsigned char md5sum[16];
unsigned char sha1sum[20];
ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
SSL_DEBUG_MSG( 2, ( "=> calc finished ssl" ) );
memcpy( &md5 , &ssl->handshake->fin_md5 , sizeof(md5_context) );
memcpy( &sha1, &ssl->handshake->fin_sha1, sizeof(sha1_context) );
/*
* SSLv3:
* hash =
* MD5( master + pad2 +
* MD5( handshake + sender + master + pad1 ) )
* + SHA1( master + pad2 +
* SHA1( handshake + sender + master + pad1 ) )
*/
#if !defined(POLARSSL_MD5_ALT)
SSL_DEBUG_BUF( 4, "finished md5 state", (unsigned char *)
md5.state, sizeof( md5.state ) );
#endif
#if !defined(POLARSSL_SHA1_ALT)
SSL_DEBUG_BUF( 4, "finished sha1 state", (unsigned char *)
sha1.state, sizeof( sha1.state ) );
#endif
sender = ( from == SSL_IS_CLIENT ) ? "CLNT"
: "SRVR";
memset( padbuf, 0x36, 48 );
md5_update( &md5, (const unsigned char *) sender, 4 );
md5_update( &md5, session->master, 48 );
md5_update( &md5, padbuf, 48 );
md5_finish( &md5, md5sum );
sha1_update( &sha1, (const unsigned char *) sender, 4 );
sha1_update( &sha1, session->master, 48 );
sha1_update( &sha1, padbuf, 40 );
sha1_finish( &sha1, sha1sum );
memset( padbuf, 0x5C, 48 );
md5_starts( &md5 );
md5_update( &md5, session->master, 48 );
md5_update( &md5, padbuf, 48 );
md5_update( &md5, md5sum, 16 );
md5_finish( &md5, buf );
sha1_starts( &sha1 );
sha1_update( &sha1, session->master, 48 );
sha1_update( &sha1, padbuf , 40 );
sha1_update( &sha1, sha1sum, 20 );
sha1_finish( &sha1, buf + 16 );
SSL_DEBUG_BUF( 3, "calc finished result", buf, 36 );
md5_free( &md5 );
sha1_free( &sha1 );
polarssl_zeroize( padbuf, sizeof( padbuf ) );
polarssl_zeroize( md5sum, sizeof( md5sum ) );
polarssl_zeroize( sha1sum, sizeof( sha1sum ) );
SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* POLARSSL_SSL_PROTO_SSL3 */
#if defined(POLARSSL_SSL_PROTO_TLS1) || defined(POLARSSL_SSL_PROTO_TLS1_1)
static void ssl_calc_finished_tls(
ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
md5_context md5;
sha1_context sha1;
unsigned char padbuf[36];
ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
SSL_DEBUG_MSG( 2, ( "=> calc finished tls" ) );
memcpy( &md5 , &ssl->handshake->fin_md5 , sizeof(md5_context) );
memcpy( &sha1, &ssl->handshake->fin_sha1, sizeof(sha1_context) );
/*
* TLSv1:
* hash = PRF( master, finished_label,
* MD5( handshake ) + SHA1( handshake ) )[0..11]
*/
#if !defined(POLARSSL_MD5_ALT)
SSL_DEBUG_BUF( 4, "finished md5 state", (unsigned char *)
md5.state, sizeof( md5.state ) );
#endif
#if !defined(POLARSSL_SHA1_ALT)
SSL_DEBUG_BUF( 4, "finished sha1 state", (unsigned char *)
sha1.state, sizeof( sha1.state ) );
#endif
sender = ( from == SSL_IS_CLIENT )
? "client finished"
: "server finished";
md5_finish( &md5, padbuf );
sha1_finish( &sha1, padbuf + 16 );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 36, buf, len );
SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
md5_free( &md5 );
sha1_free( &sha1 );
polarssl_zeroize( padbuf, sizeof( padbuf ) );
SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 */
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
static void ssl_calc_finished_tls_sha256(
ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
sha256_context sha256;
unsigned char padbuf[32];
ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
SSL_DEBUG_MSG( 2, ( "=> calc finished tls sha256" ) );
memcpy( &sha256, &ssl->handshake->fin_sha256, sizeof(sha256_context) );
/*
* TLSv1.2:
* hash = PRF( master, finished_label,
* Hash( handshake ) )[0.11]
*/
#if !defined(POLARSSL_SHA256_ALT)
SSL_DEBUG_BUF( 4, "finished sha2 state", (unsigned char *)
sha256.state, sizeof( sha256.state ) );
#endif
sender = ( from == SSL_IS_CLIENT )
? "client finished"
: "server finished";
sha256_finish( &sha256, padbuf );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 32, buf, len );
SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
sha256_free( &sha256 );
polarssl_zeroize( padbuf, sizeof( padbuf ) );
SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* POLARSSL_SHA256_C */
#if defined(POLARSSL_SHA512_C)
static void ssl_calc_finished_tls_sha384(
ssl_context *ssl, unsigned char *buf, int from )
{
int len = 12;
const char *sender;
sha512_context sha512;
unsigned char padbuf[48];
ssl_session *session = ssl->session_negotiate;
if( !session )
session = ssl->session;
SSL_DEBUG_MSG( 2, ( "=> calc finished tls sha384" ) );
memcpy( &sha512, &ssl->handshake->fin_sha512, sizeof(sha512_context) );
/*
* TLSv1.2:
* hash = PRF( master, finished_label,
* Hash( handshake ) )[0.11]
*/
#if !defined(POLARSSL_SHA512_ALT)
SSL_DEBUG_BUF( 4, "finished sha512 state", (unsigned char *)
sha512.state, sizeof( sha512.state ) );
#endif
sender = ( from == SSL_IS_CLIENT )
? "client finished"
: "server finished";
sha512_finish( &sha512, padbuf );
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 48, buf, len );
SSL_DEBUG_BUF( 3, "calc finished result", buf, len );
sha512_free( &sha512 );
polarssl_zeroize( padbuf, sizeof( padbuf ) );
SSL_DEBUG_MSG( 2, ( "<= calc finished" ) );
}
#endif /* POLARSSL_SHA512_C */
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
static void ssl_handshake_wrapup_free_hs_transform( ssl_context *ssl )
{
SSL_DEBUG_MSG( 3, ( "=> handshake wrapup: final free" ) );
/*
* Free our handshake params
*/
ssl_handshake_free( ssl->handshake );
polarssl_free( ssl->handshake );
ssl->handshake = NULL;
/*
* Free the previous transform and swith in the current one
*/
if( ssl->transform )
{
ssl_transform_free( ssl->transform );
polarssl_free( ssl->transform );
}
ssl->transform = ssl->transform_negotiate;
ssl->transform_negotiate = NULL;
SSL_DEBUG_MSG( 3, ( "<= handshake wrapup: final free" ) );
}
void ssl_handshake_wrapup( ssl_context *ssl )
{
int resume = ssl->handshake->resume;
SSL_DEBUG_MSG( 3, ( "=> handshake wrapup" ) );
#if defined(POLARSSL_SSL_RENEGOTIATION)
if( ssl->renego_status == SSL_RENEGOTIATION_IN_PROGRESS )
{
ssl->renego_status = SSL_RENEGOTIATION_DONE;
ssl->renego_records_seen = 0;
}
#endif
/*
* Free the previous session and switch in the current one
*/
if( ssl->session )
{
#if defined(POLARSSL_SSL_ENCRYPT_THEN_MAC)
/* RFC 7366 3.1: keep the EtM state */
ssl->session_negotiate->encrypt_then_mac =
ssl->session->encrypt_then_mac;
#endif
ssl_session_free( ssl->session );
polarssl_free( ssl->session );
}
ssl->session = ssl->session_negotiate;
ssl->session_negotiate = NULL;
/*
* Add cache entry
*/
if( ssl->f_set_cache != NULL &&
ssl->session->length != 0 &&
resume == 0 )
{
if( ssl->f_set_cache( ssl->p_set_cache, ssl->session ) != 0 )
SSL_DEBUG_MSG( 1, ( "cache did not store session" ) );
}
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->flight != NULL )
{
/* Cancel handshake timer */
ssl_set_timer( ssl, 0 );
/* Keep last flight around in case we need to resend it:
* we need the handshake and transform structures for that */
SSL_DEBUG_MSG( 3, ( "skip freeing handshake and transform" ) );
}
else
#endif
ssl_handshake_wrapup_free_hs_transform( ssl );
ssl->state++;
SSL_DEBUG_MSG( 3, ( "<= handshake wrapup" ) );
}
int ssl_write_finished( ssl_context *ssl )
{
int ret, hash_len;
SSL_DEBUG_MSG( 2, ( "=> write finished" ) );
/*
* Set the out_msg pointer to the correct location based on IV length
*/
if( ssl->minor_ver >= SSL_MINOR_VERSION_2 )
{
ssl->out_msg = ssl->out_iv + ssl->transform_negotiate->ivlen -
ssl->transform_negotiate->fixed_ivlen;
}
else
ssl->out_msg = ssl->out_iv;
ssl->handshake->calc_finished( ssl, ssl->out_msg + 4, ssl->endpoint );
// TODO TLS/1.2 Hash length is determined by cipher suite (Page 63)
hash_len = ( ssl->minor_ver == SSL_MINOR_VERSION_0 ) ? 36 : 12;
#if defined(POLARSSL_SSL_RENEGOTIATION)
ssl->verify_data_len = hash_len;
memcpy( ssl->own_verify_data, ssl->out_msg + 4, hash_len );
#endif
ssl->out_msglen = 4 + hash_len;
ssl->out_msgtype = 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->handshake->resume != 0 )
{
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
ssl->state = SSL_HANDSHAKE_WRAPUP;
#endif
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
ssl->state = SSL_CLIENT_CHANGE_CIPHER_SPEC;
#endif
}
else
ssl->state++;
/*
* Switch to our negotiated transform and session parameters for outbound
* data.
*/
SSL_DEBUG_MSG( 3, ( "switching to new transform spec for outbound data" ) );
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
unsigned char i;
/* Remember current epoch settings for resending */
ssl->handshake->alt_transform_out = ssl->transform_out;
memcpy( ssl->handshake->alt_out_ctr, ssl->out_ctr, 8 );
/* Set sequence_number to zero */
memset( ssl->out_ctr + 2, 0, 6 );
/* Increment epoch */
for( i = 2; i > 0; i-- )
if( ++ssl->out_ctr[i - 1] != 0 )
break;
/* The loop goes to its end iff the counter is wrapping */
if( i == 0 )
{
SSL_DEBUG_MSG( 1, ( "DTLS epoch would wrap" ) );
return( POLARSSL_ERR_SSL_COUNTER_WRAPPING );
}
}
else
#endif /* POLARSSL_SSL_PROTO_DTLS */
memset( ssl->out_ctr, 0, 8 );
ssl->transform_out = ssl->transform_negotiate;
ssl->session_out = ssl->session_negotiate;
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_activate != NULL )
{
if( ( ret = ssl_hw_record_activate( ssl, SSL_CHANNEL_OUTBOUND ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_activate", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
ssl_send_flight_completed( ssl );
#endif
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 );
}
#if defined(POLARSSL_SSL_PROTO_SSL3)
#define SSL_MAX_HASH_LEN 36
#else
#define SSL_MAX_HASH_LEN 12
#endif
int ssl_parse_finished( ssl_context *ssl )
{
int ret;
unsigned int hash_len;
unsigned char buf[SSL_MAX_HASH_LEN];
SSL_DEBUG_MSG( 2, ( "=> parse finished" ) );
ssl->handshake->calc_finished( ssl, buf, ssl->endpoint ^ 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 );
}
/* There is currently no ciphersuite using another length with TLS 1.2 */
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
hash_len = 36;
else
#endif
hash_len = 12;
if( ssl->in_msg[0] != SSL_HS_FINISHED ||
ssl->in_hslen != ssl_hs_hdr_len( ssl ) + hash_len )
{
SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_FINISHED );
}
if( safer_memcmp( ssl->in_msg + ssl_hs_hdr_len( ssl ),
buf, hash_len ) != 0 )
{
SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_FINISHED );
}
#if defined(POLARSSL_SSL_RENEGOTIATION)
ssl->verify_data_len = hash_len;
memcpy( ssl->peer_verify_data, buf, hash_len );
#endif
if( ssl->handshake->resume != 0 )
{
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
ssl->state = SSL_CLIENT_CHANGE_CIPHER_SPEC;
#endif
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
ssl->state = SSL_HANDSHAKE_WRAPUP;
#endif
}
else
ssl->state++;
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
ssl_recv_flight_completed( ssl );
#endif
SSL_DEBUG_MSG( 2, ( "<= parse finished" ) );
return( 0 );
}
static void ssl_handshake_params_init( ssl_handshake_params *handshake )
{
memset( handshake, 0, sizeof( ssl_handshake_params ) );
#if defined(POLARSSL_SSL_PROTO_SSL3) || defined(POLARSSL_SSL_PROTO_TLS1) || \
defined(POLARSSL_SSL_PROTO_TLS1_1)
md5_init( &handshake->fin_md5 );
sha1_init( &handshake->fin_sha1 );
md5_starts( &handshake->fin_md5 );
sha1_starts( &handshake->fin_sha1 );
#endif
#if defined(POLARSSL_SSL_PROTO_TLS1_2)
#if defined(POLARSSL_SHA256_C)
sha256_init( &handshake->fin_sha256 );
sha256_starts( &handshake->fin_sha256, 0 );
#endif
#if defined(POLARSSL_SHA512_C)
sha512_init( &handshake->fin_sha512 );
sha512_starts( &handshake->fin_sha512, 1 );
#endif
#endif /* POLARSSL_SSL_PROTO_TLS1_2 */
handshake->update_checksum = ssl_update_checksum_start;
handshake->sig_alg = SSL_HASH_SHA1;
#if defined(POLARSSL_DHM_C)
dhm_init( &handshake->dhm_ctx );
#endif
#if defined(POLARSSL_ECDH_C)
ecdh_init( &handshake->ecdh_ctx );
#endif
}
static void ssl_transform_init( ssl_transform *transform )
{
memset( transform, 0, sizeof(ssl_transform) );
cipher_init( &transform->cipher_ctx_enc );
cipher_init( &transform->cipher_ctx_dec );
md_init( &transform->md_ctx_enc );
md_init( &transform->md_ctx_dec );
}
void ssl_session_init( ssl_session *session )
{
memset( session, 0, sizeof(ssl_session) );
}
static int ssl_handshake_init( ssl_context *ssl )
{
/* Clear old handshake information if present */
if( ssl->transform_negotiate )
ssl_transform_free( ssl->transform_negotiate );
if( ssl->session_negotiate )
ssl_session_free( ssl->session_negotiate );
if( ssl->handshake )
ssl_handshake_free( ssl->handshake );
/*
* Either the pointers are now NULL or cleared properly and can be freed.
* Now allocate missing structures.
*/
if( ssl->transform_negotiate == NULL )
{
ssl->transform_negotiate = polarssl_malloc( sizeof(ssl_transform) );
}
if( ssl->session_negotiate == NULL )
{
ssl->session_negotiate = polarssl_malloc( sizeof(ssl_session) );
}
if( ssl->handshake == NULL )
{
ssl->handshake = polarssl_malloc( sizeof(ssl_handshake_params) );
}
/* All pointers should exist and can be directly freed without issue */
if( ssl->handshake == NULL ||
ssl->transform_negotiate == NULL ||
ssl->session_negotiate == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc() of ssl sub-contexts failed" ) );
polarssl_free( ssl->handshake );
polarssl_free( ssl->transform_negotiate );
polarssl_free( ssl->session_negotiate );
ssl->handshake = NULL;
ssl->transform_negotiate = NULL;
ssl->session_negotiate = NULL;
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
/* Initialize structures */
ssl_session_init( ssl->session_negotiate );
ssl_transform_init( ssl->transform_negotiate );
ssl_handshake_params_init( ssl->handshake );
#if defined(POLARSSL_X509_CRT_PARSE_C)
ssl->handshake->key_cert = ssl->key_cert;
#endif
/*
* We may not know yet if we're using DTLS,
* so always initiliase DTLS-specific fields.
*/
#if defined(POLARSSL_SSL_PROTO_DTLS)
ssl->handshake->alt_transform_out = ssl->transform_out;
// TODO: not the right place, we may not know endpoint yet
if( ssl->endpoint == SSL_IS_CLIENT )
ssl->handshake->retransmit_state = SSL_RETRANS_PREPARING;
else
ssl->handshake->retransmit_state = SSL_RETRANS_WAITING;
#endif
return( 0 );
}
#if defined(POLARSSL_SSL_DTLS_HELLO_VERIFY)
/* Dummy cookie callbacks for defaults */
static int ssl_cookie_write_dummy( void *ctx,
unsigned char **p, unsigned char *end,
const unsigned char *cli_id, size_t cli_id_len )
{
((void) ctx);
((void) p);
((void) end);
((void) cli_id);
((void) cli_id_len);
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
static int ssl_cookie_check_dummy( void *ctx,
const unsigned char *cookie, size_t cookie_len,
const unsigned char *cli_id, size_t cli_id_len )
{
((void) ctx);
((void) cookie);
((void) cookie_len);
((void) cli_id);
((void) cli_id_len);
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}
#endif /* POLARSSL_SSL_DTLS_HELLO_VERIFY */
/*
* Initialize an SSL context
*/
int ssl_init( ssl_context *ssl )
{
int ret;
int len = SSL_BUFFER_LEN;
memset( ssl, 0, sizeof( ssl_context ) );
/*
* Sane defaults
*/
ssl->min_major_ver = SSL_MIN_MAJOR_VERSION;
ssl->min_minor_ver = SSL_MIN_MINOR_VERSION;
ssl->max_major_ver = SSL_MAX_MAJOR_VERSION;
ssl->max_minor_ver = SSL_MAX_MINOR_VERSION;
ssl_set_ciphersuites( ssl, ssl_list_ciphersuites() );
#if defined(POLARSSL_SSL_RENEGOTIATION)
ssl->renego_max_records = SSL_RENEGO_MAX_RECORDS_DEFAULT;
memset( ssl->renego_period, 0xFF, 7 );
ssl->renego_period[7] = 0x00;
#endif
#if defined(POLARSSL_DHM_C)
if( ( ret = mpi_read_string( &ssl->dhm_P, 16,
POLARSSL_DHM_RFC5114_MODP_1024_P) ) != 0 ||
( ret = mpi_read_string( &ssl->dhm_G, 16,
POLARSSL_DHM_RFC5114_MODP_1024_G) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_read_string", ret );
return( ret );
}
#endif
/*
* Prepare base structures
*/
if( ( ssl->in_buf = polarssl_malloc( len ) ) == NULL ||
( ssl->out_buf = polarssl_malloc( len ) ) == NULL )
{
SSL_DEBUG_MSG( 1, ( "malloc(%d bytes) failed", len ) );
polarssl_free( ssl->in_buf );
ssl->in_buf = NULL;
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
memset( ssl-> in_buf, 0, SSL_BUFFER_LEN );
memset( ssl->out_buf, 0, SSL_BUFFER_LEN );
/* No error is possible, SSL_TRANSPORT_STREAM always valid */
(void) ssl_set_transport( ssl, SSL_TRANSPORT_STREAM );
#if defined(POLARSSL_SSL_ENCRYPT_THEN_MAC)
ssl->encrypt_then_mac = SSL_ETM_ENABLED;
#endif
#if defined(POLARSSL_SSL_EXTENDED_MASTER_SECRET)
ssl->extended_ms = SSL_EXTENDED_MS_ENABLED;
#endif
#if defined(POLARSSL_SSL_SESSION_TICKETS)
ssl->ticket_lifetime = SSL_DEFAULT_TICKET_LIFETIME;
#endif
#if defined(POLARSSL_SSL_SET_CURVES)
ssl->curve_list = ecp_grp_id_list( );
#endif
#if defined(POLARSSL_SSL_DTLS_HELLO_VERIFY)
ssl->f_cookie_write = ssl_cookie_write_dummy;
ssl->f_cookie_check = ssl_cookie_check_dummy;
#endif
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
ssl->anti_replay = SSL_ANTI_REPLAY_ENABLED;
#endif
#if defined(POLARSSL_SSL_PROTO_DTLS)
ssl->hs_timeout_min = SSL_DTLS_TIMEOUT_DFL_MIN;
ssl->hs_timeout_max = SSL_DTLS_TIMEOUT_DFL_MAX;
#endif
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
return( ret );
return( 0 );
}
/*
* Reset an initialized and used SSL context for re-use while retaining
* all application-set variables, function pointers and data.
*/
int ssl_session_reset( ssl_context *ssl )
{
int ret;
ssl->state = SSL_HELLO_REQUEST;
#if defined(POLARSSL_SSL_RENEGOTIATION)
ssl->renego_status = SSL_INITIAL_HANDSHAKE;
ssl->renego_records_seen = 0;
ssl->verify_data_len = 0;
memset( ssl->own_verify_data, 0, SSL_VERIFY_DATA_MAX_LEN );
memset( ssl->peer_verify_data, 0, SSL_VERIFY_DATA_MAX_LEN );
#endif
ssl->secure_renegotiation = SSL_LEGACY_RENEGOTIATION;
ssl->in_offt = NULL;
ssl->in_msg = ssl->in_buf + 13;
ssl->in_msgtype = 0;
ssl->in_msglen = 0;
ssl->in_left = 0;
#if defined(POLARSSL_SSL_PROTO_DTLS)
ssl->next_record_offset = 0;
ssl->in_epoch = 0;
#endif
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
ssl_dtls_replay_reset( ssl );
#endif
ssl->in_hslen = 0;
ssl->nb_zero = 0;
ssl->record_read = 0;
ssl->out_msg = ssl->out_buf + 13;
ssl->out_msgtype = 0;
ssl->out_msglen = 0;
ssl->out_left = 0;
#if defined(POLARSSL_SSL_CBC_RECORD_SPLITTING)
if( ssl->split_done != SSL_CBC_RECORD_SPLITTING_DISABLED )
ssl->split_done = 0;
#endif
ssl->transform_in = NULL;
ssl->transform_out = NULL;
memset( ssl->out_buf, 0, SSL_BUFFER_LEN );
memset( ssl->in_buf, 0, SSL_BUFFER_LEN );
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_reset != NULL )
{
SSL_DEBUG_MSG( 2, ( "going for ssl_hw_record_reset()" ) );
if( ( ret = ssl_hw_record_reset( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_hw_record_reset", ret );
return( POLARSSL_ERR_SSL_HW_ACCEL_FAILED );
}
}
#endif
if( ssl->transform )
{
ssl_transform_free( ssl->transform );
polarssl_free( ssl->transform );
ssl->transform = NULL;
}
if( ssl->session )
{
ssl_session_free( ssl->session );
polarssl_free( ssl->session );
ssl->session = NULL;
}
#if defined(POLARSSL_SSL_ALPN)
ssl->alpn_chosen = NULL;
#endif
#if defined(POLARSSL_SSL_DTLS_HELLO_VERIFY)
polarssl_free( ssl->cli_id );
ssl->cli_id = NULL;
ssl->cli_id_len = 0;
#endif
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
return( ret );
return( 0 );
}
#if defined(POLARSSL_SSL_SESSION_TICKETS)
static void ssl_ticket_keys_free( ssl_ticket_keys *tkeys )
{
aes_free( &tkeys->enc );
aes_free( &tkeys->dec );
polarssl_zeroize( tkeys, sizeof(ssl_ticket_keys) );
}
/*
* Allocate and initialize ticket keys
*/
static int ssl_ticket_keys_init( ssl_context *ssl )
{
int ret;
ssl_ticket_keys *tkeys;
unsigned char buf[16];
if( ssl->ticket_keys != NULL )
return( 0 );
tkeys = polarssl_malloc( sizeof(ssl_ticket_keys) );
if( tkeys == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
aes_init( &tkeys->enc );
aes_init( &tkeys->dec );
if( ( ret = ssl->f_rng( ssl->p_rng, tkeys->key_name, 16 ) ) != 0 )
{
ssl_ticket_keys_free( tkeys );
polarssl_free( tkeys );
return( ret );
}
if( ( ret = ssl->f_rng( ssl->p_rng, buf, 16 ) ) != 0 ||
( ret = aes_setkey_enc( &tkeys->enc, buf, 128 ) ) != 0 ||
( ret = aes_setkey_dec( &tkeys->dec, buf, 128 ) ) != 0 )
{
ssl_ticket_keys_free( tkeys );
polarssl_free( tkeys );
return( ret );
}
if( ( ret = ssl->f_rng( ssl->p_rng, tkeys->mac_key, 16 ) ) != 0 )
{
ssl_ticket_keys_free( tkeys );
polarssl_free( tkeys );
return( ret );
}
ssl->ticket_keys = tkeys;
return( 0 );
}
#endif /* POLARSSL_SSL_SESSION_TICKETS */
/*
* SSL set accessors
*/
void ssl_set_endpoint( ssl_context *ssl, int endpoint )
{
ssl->endpoint = endpoint;
#if defined(POLARSSL_SSL_SESSION_TICKETS) && \
defined(POLARSSL_SSL_CLI_C)
if( endpoint == SSL_IS_CLIENT )
ssl->session_tickets = SSL_SESSION_TICKETS_ENABLED;
#endif
#if defined(POLARSSL_SSL_TRUNCATED_HMAC)
if( endpoint == SSL_IS_SERVER )
ssl->trunc_hmac = SSL_TRUNC_HMAC_ENABLED;
#endif
}
int ssl_set_transport( ssl_context *ssl, int transport )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( transport == SSL_TRANSPORT_DATAGRAM )
{
ssl->transport = transport;
ssl->out_hdr = ssl->out_buf;
ssl->out_ctr = ssl->out_buf + 3;
ssl->out_len = ssl->out_buf + 11;
ssl->out_iv = ssl->out_buf + 13;
ssl->out_msg = ssl->out_buf + 13;
ssl->in_hdr = ssl->in_buf;
ssl->in_ctr = ssl->in_buf + 3;
ssl->in_len = ssl->in_buf + 11;
ssl->in_iv = ssl->in_buf + 13;
ssl->in_msg = ssl->in_buf + 13;
/* DTLS starts with TLS1.1 */
if( ssl->min_minor_ver < SSL_MINOR_VERSION_2 )
ssl->min_minor_ver = SSL_MINOR_VERSION_2;
if( ssl->max_minor_ver < SSL_MINOR_VERSION_2 )
ssl->max_minor_ver = SSL_MINOR_VERSION_2;
return( 0 );
}
#endif
if( transport == SSL_TRANSPORT_STREAM )
{
ssl->transport = transport;
ssl->out_ctr = ssl->out_buf;
ssl->out_hdr = ssl->out_buf + 8;
ssl->out_len = ssl->out_buf + 11;
ssl->out_iv = ssl->out_buf + 13;
ssl->out_msg = ssl->out_buf + 13;
ssl->in_ctr = ssl->in_buf;
ssl->in_hdr = ssl->in_buf + 8;
ssl->in_len = ssl->in_buf + 11;
ssl->in_iv = ssl->in_buf + 13;
ssl->in_msg = ssl->in_buf + 13;
return( 0 );
}
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
#if defined(POLARSSL_SSL_DTLS_ANTI_REPLAY)
void ssl_set_dtls_anti_replay( ssl_context *ssl, char mode )
{
ssl->anti_replay = mode;
}
#endif
#if defined(POLARSSL_SSL_DTLS_BADMAC_LIMIT)
void ssl_set_dtls_badmac_limit( ssl_context *ssl, unsigned limit )
{
ssl->badmac_limit = limit;
}
#endif
#if defined(POLARSSL_SSL_PROTO_DTLS)
void ssl_set_handshake_timeout( ssl_context *ssl, uint32_t min, uint32_t max )
{
ssl->hs_timeout_min = min;
ssl->hs_timeout_max = max;
}
#endif
void ssl_set_authmode( ssl_context *ssl, int authmode )
{
ssl->authmode = authmode;
}
#if defined(POLARSSL_X509_CRT_PARSE_C)
void ssl_set_verify( ssl_context *ssl,
int (*f_vrfy)(void *, x509_crt *, int, int *),
void *p_vrfy )
{
ssl->f_vrfy = f_vrfy;
ssl->p_vrfy = p_vrfy;
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
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 )
{
if( p_recv != p_send )
{
ssl->f_recv = NULL;
ssl->f_send = NULL;
ssl->p_bio = NULL;
return;
}
ssl->f_recv = f_recv;
ssl->f_send = f_send;
ssl->p_bio = p_send;
}
void ssl_set_bio_timeout( ssl_context *ssl,
void *p_bio,
int (*f_send)(void *, const unsigned char *, size_t),
int (*f_recv)(void *, unsigned char *, size_t),
int (*f_recv_timeout)(void *, unsigned char *, size_t, uint32_t),
uint32_t timeout )
{
ssl->p_bio = p_bio;
ssl->f_send = f_send;
ssl->f_recv = f_recv;
ssl->f_recv_timeout = f_recv_timeout;
ssl->read_timeout = timeout;
}
#if defined(POLARSSL_SSL_SRV_C)
void ssl_set_session_cache( ssl_context *ssl,
int (*f_get_cache)(void *, ssl_session *), void *p_get_cache,
int (*f_set_cache)(void *, const ssl_session *), void *p_set_cache )
{
ssl->f_get_cache = f_get_cache;
ssl->p_get_cache = p_get_cache;
ssl->f_set_cache = f_set_cache;
ssl->p_set_cache = p_set_cache;
}
#endif /* POLARSSL_SSL_SRV_C */
#if defined(POLARSSL_SSL_CLI_C)
int ssl_set_session( ssl_context *ssl, const ssl_session *session )
{
int ret;
if( ssl == NULL ||
session == NULL ||
ssl->session_negotiate == NULL ||
ssl->endpoint != SSL_IS_CLIENT )
{
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
if( ( ret = ssl_session_copy( ssl->session_negotiate, session ) ) != 0 )
return( ret );
ssl->handshake->resume = 1;
return( 0 );
}
#endif /* POLARSSL_SSL_CLI_C */
void ssl_set_ciphersuites( ssl_context *ssl, const int *ciphersuites )
{
ssl->ciphersuite_list[SSL_MINOR_VERSION_0] = ciphersuites;
ssl->ciphersuite_list[SSL_MINOR_VERSION_1] = ciphersuites;
ssl->ciphersuite_list[SSL_MINOR_VERSION_2] = ciphersuites;
ssl->ciphersuite_list[SSL_MINOR_VERSION_3] = ciphersuites;
}
void ssl_set_ciphersuites_for_version( ssl_context *ssl,
const int *ciphersuites,
int major, int minor )
{
if( major != SSL_MAJOR_VERSION_3 )
return;
if( minor < SSL_MINOR_VERSION_0 || minor > SSL_MINOR_VERSION_3 )
return;
ssl->ciphersuite_list[minor] = ciphersuites;
}
#if defined(POLARSSL_X509_CRT_PARSE_C)
/* Add a new (empty) key_cert entry an return a pointer to it */
static ssl_key_cert *ssl_add_key_cert( ssl_context *ssl )
{
ssl_key_cert *key_cert, *last;
key_cert = polarssl_malloc( sizeof(ssl_key_cert) );
if( key_cert == NULL )
return( NULL );
memset( key_cert, 0, sizeof( ssl_key_cert ) );
/* Append the new key_cert to the (possibly empty) current list */
if( ssl->key_cert == NULL )
{
ssl->key_cert = key_cert;
if( ssl->handshake != NULL )
ssl->handshake->key_cert = key_cert;
}
else
{
last = ssl->key_cert;
while( last->next != NULL )
last = last->next;
last->next = key_cert;
}
return( key_cert );
}
void ssl_set_ca_chain( ssl_context *ssl, x509_crt *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;
}
int ssl_set_own_cert( ssl_context *ssl, x509_crt *own_cert,
pk_context *pk_key )
{
ssl_key_cert *key_cert = ssl_add_key_cert( ssl );
if( key_cert == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
key_cert->cert = own_cert;
key_cert->key = pk_key;
return( 0 );
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
int ssl_set_psk( ssl_context *ssl, const unsigned char *psk, size_t psk_len,
const unsigned char *psk_identity, size_t psk_identity_len )
{
if( psk == NULL || psk_identity == NULL )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
if( psk_len > POLARSSL_PSK_MAX_LEN )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
if( ssl->psk != NULL || ssl->psk_identity != NULL )
{
polarssl_free( ssl->psk );
polarssl_free( ssl->psk_identity );
}
if( ( ssl->psk = polarssl_malloc( psk_len ) ) == NULL ||
( ssl->psk_identity = polarssl_malloc( psk_identity_len ) ) == NULL )
{
polarssl_free( ssl->psk );
ssl->psk = NULL;
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
}
ssl->psk_len = psk_len;
ssl->psk_identity_len = psk_identity_len;
memcpy( ssl->psk, psk, ssl->psk_len );
memcpy( ssl->psk_identity, psk_identity, ssl->psk_identity_len );
return( 0 );
}
void ssl_set_psk_cb( ssl_context *ssl,
int (*f_psk)(void *, ssl_context *, const unsigned char *,
size_t),
void *p_psk )
{
ssl->f_psk = f_psk;
ssl->p_psk = p_psk;
}
#endif /* POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(POLARSSL_DHM_C)
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_P, 16, dhm_P ) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_read_string", ret );
return( ret );
}
if( ( ret = mpi_read_string( &ssl->dhm_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_P, &dhm_ctx->P ) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_copy", ret );
return( ret );
}
if( ( ret = mpi_copy( &ssl->dhm_G, &dhm_ctx->G ) ) != 0 )
{
SSL_DEBUG_RET( 1, "mpi_copy", ret );
return( ret );
}
return( 0 );
}
#endif /* POLARSSL_DHM_C */
#if defined(POLARSSL_SSL_SET_CURVES)
/*
* Set the allowed elliptic curves
*/
void ssl_set_curves( ssl_context *ssl, const ecp_group_id *curve_list )
{
ssl->curve_list = curve_list;
}
#endif
#if defined(POLARSSL_SSL_SERVER_NAME_INDICATION)
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 );
if( ssl->hostname_len + 1 == 0 )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
ssl->hostname = polarssl_malloc( ssl->hostname_len + 1 );
if( ssl->hostname == NULL )
return( POLARSSL_ERR_SSL_MALLOC_FAILED );
memcpy( ssl->hostname, (const unsigned char *) hostname,
ssl->hostname_len );
ssl->hostname[ssl->hostname_len] = '\0';
return( 0 );
}
void ssl_set_sni( ssl_context *ssl,
int (*f_sni)(void *, ssl_context *,
const unsigned char *, size_t),
void *p_sni )
{
ssl->f_sni = f_sni;
ssl->p_sni = p_sni;
}
#endif /* POLARSSL_SSL_SERVER_NAME_INDICATION */
#if defined(POLARSSL_SSL_ALPN)
int ssl_set_alpn_protocols( ssl_context *ssl, const char **protos )
{
size_t cur_len, tot_len;
const char **p;
/*
* "Empty strings MUST NOT be included and byte strings MUST NOT be
* truncated". Check lengths now rather than later.
*/
tot_len = 0;
for( p = protos; *p != NULL; p++ )
{
cur_len = strlen( *p );
tot_len += cur_len;
if( cur_len == 0 || cur_len > 255 || tot_len > 65535 )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
ssl->alpn_list = protos;
return( 0 );
}
const char *ssl_get_alpn_protocol( const ssl_context *ssl )
{
return( ssl->alpn_chosen );
}
#endif /* POLARSSL_SSL_ALPN */
static int ssl_check_version( const ssl_context *ssl, int major, int minor )
{
if( major < SSL_MIN_MAJOR_VERSION || major > SSL_MAX_MAJOR_VERSION ||
minor < SSL_MIN_MINOR_VERSION || minor > SSL_MAX_MINOR_VERSION )
{
return( -1 );
}
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
minor < SSL_MINOR_VERSION_2 )
{
return( -1 );
}
#else
((void) ssl);
#endif
return( 0 );
}
int ssl_set_max_version( ssl_context *ssl, int major, int minor )
{
if( ssl_check_version( ssl, major, minor ) != 0 )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
ssl->max_major_ver = major;
ssl->max_minor_ver = minor;
return( 0 );
}
int ssl_set_min_version( ssl_context *ssl, int major, int minor )
{
if( ssl_check_version( ssl, major, minor ) != 0 )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
ssl->min_major_ver = major;
ssl->min_minor_ver = minor;
return( 0 );
}
#if defined(POLARSSL_SSL_FALLBACK_SCSV) && defined(POLARSSL_SSL_CLI_C)
void ssl_set_fallback( ssl_context *ssl, char fallback )
{
ssl->fallback = fallback;
}
#endif
#if defined(POLARSSL_SSL_ENCRYPT_THEN_MAC)
void ssl_set_encrypt_then_mac( ssl_context *ssl, char etm )
{
ssl->encrypt_then_mac = etm;
}
#endif
#if defined(POLARSSL_SSL_EXTENDED_MASTER_SECRET)
void ssl_set_extended_master_secret( ssl_context *ssl, char ems )
{
ssl->extended_ms = ems;
}
#endif
void ssl_set_arc4_support( ssl_context *ssl, char arc4 )
{
ssl->arc4_disabled = arc4;
}
#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code )
{
if( mfl_code >= SSL_MAX_FRAG_LEN_INVALID ||
mfl_code_to_length[mfl_code] > SSL_MAX_CONTENT_LEN )
{
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
ssl->mfl_code = mfl_code;
return( 0 );
}
#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
#if defined(POLARSSL_SSL_TRUNCATED_HMAC)
int ssl_set_truncated_hmac( ssl_context *ssl, int truncate )
{
ssl->trunc_hmac = truncate;
return( 0 );
}
#endif /* POLARSSL_SSL_TRUNCATED_HMAC */
#if defined(POLARSSL_SSL_CBC_RECORD_SPLITTING)
void ssl_set_cbc_record_splitting( ssl_context *ssl, char split )
{
ssl->split_done = split;
}
#endif
void ssl_legacy_renegotiation( ssl_context *ssl, int allow_legacy )
{
ssl->allow_legacy_renegotiation = allow_legacy;
}
#if defined(POLARSSL_SSL_RENEGOTIATION)
void ssl_set_renegotiation( ssl_context *ssl, int renegotiation )
{
ssl->disable_renegotiation = renegotiation;
}
void ssl_set_renegotiation_enforced( ssl_context *ssl, int max_records )
{
ssl->renego_max_records = max_records;
}
void ssl_set_renegotiation_period( ssl_context *ssl,
const unsigned char period[8] )
{
memcpy( ssl->renego_period, period, 8 );
}
#endif /* POLARSSL_SSL_RENEGOTIATION */
#if defined(POLARSSL_SSL_SESSION_TICKETS)
int ssl_set_session_tickets( ssl_context *ssl, int use_tickets )
{
ssl->session_tickets = use_tickets;
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
return( 0 );
#endif
if( use_tickets == SSL_SESSION_TICKETS_DISABLED )
return( 0 );
if( ssl->f_rng == NULL )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
return( ssl_ticket_keys_init( ssl ) );
}
void ssl_set_session_ticket_lifetime( ssl_context *ssl, int lifetime )
{
ssl->ticket_lifetime = lifetime;
}
#endif /* POLARSSL_SSL_SESSION_TICKETS */
/*
* 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 )
{
if( ssl->session != NULL )
return( ssl->session->verify_result );
if( ssl->session_negotiate != NULL )
return( ssl->session_negotiate->verify_result );
return( -1 );
}
const char *ssl_get_ciphersuite( const ssl_context *ssl )
{
if( ssl == NULL || ssl->session == NULL )
return( NULL );
return ssl_get_ciphersuite_name( ssl->session->ciphersuite );
}
const char *ssl_get_version( const ssl_context *ssl )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
switch( ssl->minor_ver )
{
case SSL_MINOR_VERSION_2:
return( "DTLSv1.0" );
case SSL_MINOR_VERSION_3:
return( "DTLSv1.2" );
default:
return( "unknown (DTLS)" );
}
}
#endif
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" );
case SSL_MINOR_VERSION_3:
return( "TLSv1.2" );
default:
return( "unknown" );
}
}
int ssl_get_record_expansion( const ssl_context *ssl )
{
int transform_expansion;
const ssl_transform *transform = ssl->transform_out;
#if defined(POLARSSL_ZLIB_SUPPORT)
if( ssl->session_out->compression != SSL_COMPRESS_NULL )
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
if( transform == NULL )
return( ssl_hdr_len( ssl ) );
switch( cipher_get_cipher_mode( &transform->cipher_ctx_enc ) )
{
case POLARSSL_MODE_GCM:
case POLARSSL_MODE_CCM:
case POLARSSL_MODE_STREAM:
transform_expansion = transform->minlen;
break;
case POLARSSL_MODE_CBC:
transform_expansion = transform->maclen
+ cipher_get_block_size( &transform->cipher_ctx_enc );
break;
default:
SSL_DEBUG_MSG( 0, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
return( ssl_hdr_len( ssl ) + transform_expansion );
}
#if defined(POLARSSL_X509_CRT_PARSE_C)
const x509_crt *ssl_get_peer_cert( const ssl_context *ssl )
{
if( ssl == NULL || ssl->session == NULL )
return( NULL );
return( ssl->session->peer_cert );
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
#if defined(POLARSSL_SSL_CLI_C)
int ssl_get_session( const ssl_context *ssl, ssl_session *dst )
{
if( ssl == NULL ||
dst == NULL ||
ssl->session == NULL ||
ssl->endpoint != SSL_IS_CLIENT )
{
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
return( ssl_session_copy( dst, ssl->session ) );
}
#endif /* POLARSSL_SSL_CLI_C */
/*
* Perform a single step of the SSL handshake
*/
int ssl_handshake_step( ssl_context *ssl )
{
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT )
ret = ssl_handshake_client_step( ssl );
#endif
#if defined(POLARSSL_SSL_SRV_C)
if( ssl->endpoint == SSL_IS_SERVER )
ret = ssl_handshake_server_step( ssl );
#endif
return( ret );
}
/*
* Perform the SSL handshake
*/
int ssl_handshake( ssl_context *ssl )
{
int ret = 0;
SSL_DEBUG_MSG( 2, ( "=> handshake" ) );
while( ssl->state != SSL_HANDSHAKE_OVER )
{
ret = ssl_handshake_step( ssl );
if( ret != 0 )
break;
}
SSL_DEBUG_MSG( 2, ( "<= handshake" ) );
return( ret );
}
#if defined(POLARSSL_SSL_RENEGOTIATION)
#if defined(POLARSSL_SSL_SRV_C)
/*
* Write HelloRequest to request renegotiation on server
*/
static int ssl_write_hello_request( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> write hello request" ) );
ssl->out_msglen = 4;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = SSL_HS_HELLO_REQUEST;
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= write hello request" ) );
return( 0 );
}
#endif /* POLARSSL_SSL_SRV_C */
/*
* Actually renegotiate current connection, triggered by either:
* - any side: calling ssl_renegotiate(),
* - client: receiving a HelloRequest during ssl_read(),
* - server: receiving any handshake message on server during ssl_read() after
* the initial handshake is completed.
* If the handshake doesn't complete due to waiting for I/O, it will continue
* during the next calls to ssl_renegotiate() or ssl_read() respectively.
*/
static int ssl_start_renegotiation( ssl_context *ssl )
{
int ret;
SSL_DEBUG_MSG( 2, ( "=> renegotiate" ) );
if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
return( ret );
/* RFC 6347 4.2.2: "[...] the HelloRequest will have message_seq = 0 and
* the ServerHello will have message_seq = 1" */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->renego_status == SSL_RENEGOTIATION_PENDING )
{
if( ssl->endpoint == SSL_IS_SERVER )
ssl->handshake->out_msg_seq = 1;
else
ssl->handshake->in_msg_seq = 1;
}
#endif
ssl->state = SSL_HELLO_REQUEST;
ssl->renego_status = SSL_RENEGOTIATION_IN_PROGRESS;
if( ( ret = ssl_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
SSL_DEBUG_MSG( 2, ( "<= renegotiate" ) );
return( 0 );
}
/*
* Renegotiate current connection on client,
* or request renegotiation on server
*/
int ssl_renegotiate( ssl_context *ssl )
{
int ret = POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE;
#if defined(POLARSSL_SSL_SRV_C)
/* On server, just send the request */
if( ssl->endpoint == SSL_IS_SERVER )
{
if( ssl->state != SSL_HANDSHAKE_OVER )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
ssl->renego_status = SSL_RENEGOTIATION_PENDING;
/* Did we already try/start sending HelloRequest? */
if( ssl->out_left != 0 )
return( ssl_flush_output( ssl ) );
return( ssl_write_hello_request( ssl ) );
}
#endif /* POLARSSL_SSL_SRV_C */
#if defined(POLARSSL_SSL_CLI_C)
/*
* On client, either start the renegotiation process or,
* if already in progress, continue the handshake
*/
if( ssl->renego_status != SSL_RENEGOTIATION_IN_PROGRESS )
{
if( ssl->state != SSL_HANDSHAKE_OVER )
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
if( ( ret = ssl_start_renegotiation( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_start_renegotiation", ret );
return( ret );
}
}
else
{
if( ( ret = ssl_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
}
#endif /* POLARSSL_SSL_CLI_C */
return( ret );
}
/*
* Check record counters and renegotiate if they're above the limit.
*/
static int ssl_check_ctr_renegotiate( ssl_context *ssl )
{
if( ssl->state != SSL_HANDSHAKE_OVER ||
ssl->renego_status == SSL_RENEGOTIATION_PENDING ||
ssl->disable_renegotiation == SSL_RENEGOTIATION_DISABLED )
{
return( 0 );
}
// TODO: adapt for DTLS
if( memcmp( ssl->in_ctr, ssl->renego_period, 8 ) <= 0 &&
memcmp( ssl->out_ctr, ssl->renego_period, 8 ) <= 0 )
{
return( 0 );
}
SSL_DEBUG_MSG( 0, ( "record counter limit reached: renegotiate" ) );
return( ssl_renegotiate( ssl ) );
}
#endif /* POLARSSL_SSL_RENEGOTIATION */
/*
* Receive application data decrypted from the SSL layer
*/
int ssl_read( ssl_context *ssl, unsigned char *buf, size_t len )
{
int ret, record_read = 0;
size_t n;
SSL_DEBUG_MSG( 2, ( "=> read" ) );
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
if( ( ret = ssl_flush_output( ssl ) ) != 0 )
return( ret );
if( ssl->handshake != NULL &&
ssl->handshake->retransmit_state == SSL_RETRANS_SENDING )
{
if( ( ret = ssl_resend( ssl ) ) != 0 )
return( ret );
}
}
#endif
#if defined(POLARSSL_SSL_RENEGOTIATION)
if( ( ret = ssl_check_ctr_renegotiate( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_check_ctr_renegotiate", ret );
return( ret );
}
#endif
if( ssl->state != SSL_HANDSHAKE_OVER )
{
ret = ssl_handshake( ssl );
if( ret == POLARSSL_ERR_SSL_WAITING_SERVER_HELLO_RENEGO )
{
record_read = 1;
}
else if( ret != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
}
if( ssl->in_offt == NULL )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
/* Start timer if not already running */
if( ssl->time_limit == 0 )
ssl_set_timer( ssl, ssl->read_timeout );
#endif
if( ! record_read )
{
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 defined(POLARSSL_SSL_RENEGOTIATION)
if( ssl->in_msgtype == SSL_MSG_HANDSHAKE )
{
SSL_DEBUG_MSG( 1, ( "received handshake message" ) );
#if defined(POLARSSL_SSL_CLI_C)
if( ssl->endpoint == SSL_IS_CLIENT &&
( ssl->in_msg[0] != SSL_HS_HELLO_REQUEST ||
ssl->in_hslen != ssl_hs_hdr_len( ssl ) ) )
{
SSL_DEBUG_MSG( 1, ( "handshake received (not HelloRequest)" ) );
/* With DTLS, drop the packet (probably from last handshake) */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
return( POLARSSL_ERR_NET_WANT_READ );
#endif
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ssl->endpoint == SSL_IS_SERVER &&
ssl->in_msg[0] != SSL_HS_CLIENT_HELLO )
{
SSL_DEBUG_MSG( 1, ( "handshake received (not ClientHello)" ) );
/* With DTLS, drop the packet (probably from last handshake) */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
return( POLARSSL_ERR_NET_WANT_READ );
#endif
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
#endif
if( ssl->disable_renegotiation == SSL_RENEGOTIATION_DISABLED ||
( ssl->secure_renegotiation == SSL_LEGACY_RENEGOTIATION &&
ssl->allow_legacy_renegotiation ==
SSL_LEGACY_NO_RENEGOTIATION ) )
{
SSL_DEBUG_MSG( 3, ( "refusing renegotiation, sending alert" ) );
#if defined(POLARSSL_SSL_PROTO_SSL3)
if( ssl->minor_ver == SSL_MINOR_VERSION_0 )
{
/*
* SSLv3 does not have a "no_renegotiation" alert
*/
if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
}
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 )
{
if( ( ret = ssl_send_alert_message( ssl,
SSL_ALERT_LEVEL_WARNING,
SSL_ALERT_MSG_NO_RENEGOTIATION ) ) != 0 )
{
return( ret );
}
}
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 );
}
}
else
{
/* DTLS clients need to know renego is server-initiated */
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
ssl->endpoint == SSL_IS_CLIENT )
{
ssl->renego_status = SSL_RENEGOTIATION_PENDING;
}
#endif
ret = ssl_start_renegotiation( ssl );
if( ret == POLARSSL_ERR_SSL_WAITING_SERVER_HELLO_RENEGO )
{
record_read = 1;
}
else if( ret != 0 )
{
SSL_DEBUG_RET( 1, "ssl_start_renegotiation", ret );
return( ret );
}
}
/* If a non-handshake record was read during renego, fallthrough,
* else tell the user they should call ssl_read() again */
if( ! record_read )
return( POLARSSL_ERR_NET_WANT_READ );
}
else if( ssl->renego_status == SSL_RENEGOTIATION_PENDING )
{
if( ssl->renego_max_records >= 0 )
{
if( ++ssl->renego_records_seen > ssl->renego_max_records )
{
SSL_DEBUG_MSG( 1, ( "renegotiation requested, "
"but not honored by client" ) );
return( POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE );
}
}
}
#endif /* POLARSSL_SSL_RENEGOTIATION */
/* Fatal and closure alerts handled by ssl_read_record() */
if( ssl->in_msgtype == SSL_MSG_ALERT )
{
SSL_DEBUG_MSG( 2, ( "ignoring non-fatal non-closure alert" ) );
return( POLARSSL_ERR_NET_WANT_READ );
}
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;
#if defined(POLARSSL_SSL_PROTO_DTLS)
/* We're going to return something now, cancel timer,
* except if handshake (renegotiation) is in progress */
if( ssl->state == SSL_HANDSHAKE_OVER )
ssl_set_timer( ssl, 0 );
/* If we requested renego but received AppData, resend HelloRequest.
* Do it now, after setting in_offt, to avoid taking this branch
* again if ssl_write_hello_request() returns WANT_WRITE */
#if defined(POLARSSL_SSL_SRV_C) && defined(POLARSSL_SSL_RENEGOTIATION)
if( ssl->endpoint == SSL_IS_SERVER &&
ssl->renego_status == SSL_RENEGOTIATION_PENDING )
{
if( ( ret = ssl_resend_hello_request( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_resend_hello_request", ret );
return( ret );
}
}
#endif /* POLARSSL_SSL_SRV_C && POLARSSL_SSL_RENEGOTIATION */
#endif
}
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
*/
#if defined(POLARSSL_SSL_CBC_RECORD_SPLITTING)
static int ssl_write_real( ssl_context *ssl, const unsigned char *buf, size_t len )
#else
int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
#endif
{
int ret;
#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
unsigned int max_len;
#endif
SSL_DEBUG_MSG( 2, ( "=> write" ) );
#if defined(POLARSSL_SSL_RENEGOTIATION)
if( ( ret = ssl_check_ctr_renegotiate( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_check_ctr_renegotiate", ret );
return( ret );
}
#endif
if( ssl->state != SSL_HANDSHAKE_OVER )
{
if( ( ret = ssl_handshake( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_handshake", ret );
return( ret );
}
}
#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
/*
* Assume mfl_code is correct since it was checked when set
*/
max_len = mfl_code_to_length[ssl->mfl_code];
/*
* Check if a smaller max length was negotiated
*/
if( ssl->session_out != NULL &&
mfl_code_to_length[ssl->session_out->mfl_code] < max_len )
{
max_len = mfl_code_to_length[ssl->session_out->mfl_code];
}
if( len > max_len )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( ssl->transport == SSL_TRANSPORT_DATAGRAM )
{
SSL_DEBUG_MSG( 1, ( "fragment larger than the (negotiated) "
"maximum fragment length: %d > %d",
len, max_len ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
else
#endif
len = max_len;
}
#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
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 = len;
ssl->out_msgtype = SSL_MSG_APPLICATION_DATA;
memcpy( ssl->out_msg, buf, len );
if( ( ret = ssl_write_record( ssl ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_write_record", ret );
return( ret );
}
}
SSL_DEBUG_MSG( 2, ( "<= write" ) );
return( (int) len );
}
/*
* Write application data, doing 1/n-1 splitting if necessary.
*
* With non-blocking I/O, ssl_write_real() may return WANT_WRITE,
* then the caller will call us again with the same arguments, so
* remember wether we already did the split or not.
*/
#if defined(POLARSSL_SSL_CBC_RECORD_SPLITTING)
int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
{
int ret;
if( ssl->split_done == SSL_CBC_RECORD_SPLITTING_DISABLED ||
len <= 1 ||
ssl->minor_ver > SSL_MINOR_VERSION_1 ||
cipher_get_cipher_mode( &ssl->transform_out->cipher_ctx_enc )
!= POLARSSL_MODE_CBC )
{
return( ssl_write_real( ssl, buf, len ) );
}
if( ssl->split_done == 0 )
{
if( ( ret = ssl_write_real( ssl, buf, 1 ) ) <= 0 )
return( ret );
ssl->split_done = 1;
}
if( ( ret = ssl_write_real( ssl, buf + 1, len - 1 ) ) <= 0 )
return( ret );
ssl->split_done = 0;
return( ret + 1 );
}
#endif /* POLARSSL_SSL_CBC_RECORD_SPLITTING */
/*
* 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( ssl->out_left != 0 )
return( ssl_flush_output( ssl ) );
if( ssl->state == SSL_HANDSHAKE_OVER )
{
if( ( ret = ssl_send_alert_message( ssl,
SSL_ALERT_LEVEL_WARNING,
SSL_ALERT_MSG_CLOSE_NOTIFY ) ) != 0 )
{
SSL_DEBUG_RET( 1, "ssl_send_alert_message", ret );
return( ret );
}
}
SSL_DEBUG_MSG( 2, ( "<= write close notify" ) );
return( 0 );
}
void ssl_transform_free( ssl_transform *transform )
{
if( transform == NULL )
return;
#if defined(POLARSSL_ZLIB_SUPPORT)
deflateEnd( &transform->ctx_deflate );
inflateEnd( &transform->ctx_inflate );
#endif
cipher_free( &transform->cipher_ctx_enc );
cipher_free( &transform->cipher_ctx_dec );
md_free( &transform->md_ctx_enc );
md_free( &transform->md_ctx_dec );
polarssl_zeroize( transform, sizeof( ssl_transform ) );
}
#if defined(POLARSSL_X509_CRT_PARSE_C)
static void ssl_key_cert_free( ssl_key_cert *key_cert )
{
ssl_key_cert *cur = key_cert, *next;
while( cur != NULL )
{
next = cur->next;
if( cur->key_own_alloc )
{
pk_free( cur->key );
polarssl_free( cur->key );
}
polarssl_free( cur );
cur = next;
}
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
void ssl_handshake_free( ssl_handshake_params *handshake )
{
if( handshake == NULL )
return;
#if defined(POLARSSL_DHM_C)
dhm_free( &handshake->dhm_ctx );
#endif
#if defined(POLARSSL_ECDH_C)
ecdh_free( &handshake->ecdh_ctx );
#endif
#if defined(POLARSSL_ECDH_C) || defined(POLARSSL_ECDSA_C)
/* explicit void pointer cast for buggy MS compiler */
polarssl_free( (void *) handshake->curves );
#endif
#if defined(POLARSSL_X509_CRT_PARSE_C) && \
defined(POLARSSL_SSL_SERVER_NAME_INDICATION)
/*
* Free only the linked list wrapper, not the keys themselves
* since the belong to the SNI callback
*/
if( handshake->sni_key_cert != NULL )
{
ssl_key_cert *cur = handshake->sni_key_cert, *next;
while( cur != NULL )
{
next = cur->next;
polarssl_free( cur );
cur = next;
}
}
#endif /* POLARSSL_X509_CRT_PARSE_C && POLARSSL_SSL_SERVER_NAME_INDICATION */
#if defined(POLARSSL_SSL_PROTO_DTLS)
polarssl_free( handshake->verify_cookie );
polarssl_free( handshake->hs_msg );
ssl_flight_free( handshake->flight );
#endif
polarssl_zeroize( handshake, sizeof( ssl_handshake_params ) );
}
void ssl_session_free( ssl_session *session )
{
if( session == NULL )
return;
#if defined(POLARSSL_X509_CRT_PARSE_C)
if( session->peer_cert != NULL )
{
x509_crt_free( session->peer_cert );
polarssl_free( session->peer_cert );
}
#endif
#if defined(POLARSSL_SSL_SESSION_TICKETS)
polarssl_free( session->ticket );
#endif
polarssl_zeroize( session, sizeof( ssl_session ) );
}
/*
* Free an SSL context
*/
void ssl_free( ssl_context *ssl )
{
if( ssl == NULL )
return;
SSL_DEBUG_MSG( 2, ( "=> free" ) );
if( ssl->out_buf != NULL )
{
polarssl_zeroize( ssl->out_buf, SSL_BUFFER_LEN );
polarssl_free( ssl->out_buf );
}
if( ssl->in_buf != NULL )
{
polarssl_zeroize( ssl->in_buf, SSL_BUFFER_LEN );
polarssl_free( ssl->in_buf );
}
#if defined(POLARSSL_ZLIB_SUPPORT)
if( ssl->compress_buf != NULL )
{
polarssl_zeroize( ssl->compress_buf, SSL_BUFFER_LEN );
polarssl_free( ssl->compress_buf );
}
#endif
#if defined(POLARSSL_DHM_C)
mpi_free( &ssl->dhm_P );
mpi_free( &ssl->dhm_G );
#endif
if( ssl->transform )
{
ssl_transform_free( ssl->transform );
polarssl_free( ssl->transform );
}
if( ssl->handshake )
{
ssl_handshake_free( ssl->handshake );
ssl_transform_free( ssl->transform_negotiate );
ssl_session_free( ssl->session_negotiate );
polarssl_free( ssl->handshake );
polarssl_free( ssl->transform_negotiate );
polarssl_free( ssl->session_negotiate );
}
if( ssl->session )
{
ssl_session_free( ssl->session );
polarssl_free( ssl->session );
}
#if defined(POLARSSL_SSL_SESSION_TICKETS)
if( ssl->ticket_keys )
{
ssl_ticket_keys_free( ssl->ticket_keys );
polarssl_free( ssl->ticket_keys );
}
#endif
#if defined(POLARSSL_SSL_SERVER_NAME_INDICATION)
if( ssl->hostname != NULL )
{
polarssl_zeroize( ssl->hostname, ssl->hostname_len );
polarssl_free( ssl->hostname );
ssl->hostname_len = 0;
}
#endif
#if defined(POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( ssl->psk != NULL )
{
polarssl_zeroize( ssl->psk, ssl->psk_len );
polarssl_zeroize( ssl->psk_identity, ssl->psk_identity_len );
polarssl_free( ssl->psk );
polarssl_free( ssl->psk_identity );
ssl->psk_len = 0;
ssl->psk_identity_len = 0;
}
#endif
#if defined(POLARSSL_X509_CRT_PARSE_C)
ssl_key_cert_free( ssl->key_cert );
#endif
#if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
if( ssl_hw_record_finish != NULL )
{
SSL_DEBUG_MSG( 2, ( "going for ssl_hw_record_finish()" ) );
ssl_hw_record_finish( ssl );
}
#endif
#if defined(POLARSSL_SSL_DTLS_HELLO_VERIFY)
polarssl_free( ssl->cli_id );
#endif
SSL_DEBUG_MSG( 2, ( "<= free" ) );
/* Actually clear after last debug message */
polarssl_zeroize( ssl, sizeof( ssl_context ) );
}
#if defined(POLARSSL_PK_C)
/*
* Convert between POLARSSL_PK_XXX and SSL_SIG_XXX
*/
unsigned char ssl_sig_from_pk( pk_context *pk )
{
#if defined(POLARSSL_RSA_C)
if( pk_can_do( pk, POLARSSL_PK_RSA ) )
return( SSL_SIG_RSA );
#endif
#if defined(POLARSSL_ECDSA_C)
if( pk_can_do( pk, POLARSSL_PK_ECDSA ) )
return( SSL_SIG_ECDSA );
#endif
return( SSL_SIG_ANON );
}
pk_type_t ssl_pk_alg_from_sig( unsigned char sig )
{
switch( sig )
{
#if defined(POLARSSL_RSA_C)
case SSL_SIG_RSA:
return( POLARSSL_PK_RSA );
#endif
#if defined(POLARSSL_ECDSA_C)
case SSL_SIG_ECDSA:
return( POLARSSL_PK_ECDSA );
#endif
default:
return( POLARSSL_PK_NONE );
}
}
#endif /* POLARSSL_PK_C */
/*
* Convert between SSL_HASH_XXX and POLARSSL_MD_XXX
*/
md_type_t ssl_md_alg_from_hash( unsigned char hash )
{
switch( hash )
{
#if defined(POLARSSL_MD5_C)
case SSL_HASH_MD5:
return( POLARSSL_MD_MD5 );
#endif
#if defined(POLARSSL_SHA1_C)
case SSL_HASH_SHA1:
return( POLARSSL_MD_SHA1 );
#endif
#if defined(POLARSSL_SHA256_C)
case SSL_HASH_SHA224:
return( POLARSSL_MD_SHA224 );
case SSL_HASH_SHA256:
return( POLARSSL_MD_SHA256 );
#endif
#if defined(POLARSSL_SHA512_C)
case SSL_HASH_SHA384:
return( POLARSSL_MD_SHA384 );
case SSL_HASH_SHA512:
return( POLARSSL_MD_SHA512 );
#endif
default:
return( POLARSSL_MD_NONE );
}
}
#if defined(POLARSSL_SSL_SET_CURVES)
/*
* Check is a curve proposed by the peer is in our list.
* Return 1 if we're willing to use it, 0 otherwise.
*/
int ssl_curve_is_acceptable( const ssl_context *ssl, ecp_group_id grp_id )
{
const ecp_group_id *gid;
for( gid = ssl->curve_list; *gid != POLARSSL_ECP_DP_NONE; gid++ )
if( *gid == grp_id )
return( 1 );
return( 0 );
}
#endif /* POLARSSL_SSL_SET_CURVES */
#if defined(POLARSSL_X509_CRT_PARSE_C)
int ssl_check_cert_usage( const x509_crt *cert,
const ssl_ciphersuite_t *ciphersuite,
int cert_endpoint )
{
#if defined(POLARSSL_X509_CHECK_KEY_USAGE)
int usage = 0;
#endif
#if defined(POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE)
const char *ext_oid;
size_t ext_len;
#endif
#if !defined(POLARSSL_X509_CHECK_KEY_USAGE) && \
!defined(POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE)
((void) cert);
((void) cert_endpoint);
#endif
#if defined(POLARSSL_X509_CHECK_KEY_USAGE)
if( cert_endpoint == SSL_IS_SERVER )
{
/* Server part of the key exchange */
switch( ciphersuite->key_exchange )
{
case POLARSSL_KEY_EXCHANGE_RSA:
case POLARSSL_KEY_EXCHANGE_RSA_PSK:
usage = KU_KEY_ENCIPHERMENT;
break;
case POLARSSL_KEY_EXCHANGE_DHE_RSA:
case POLARSSL_KEY_EXCHANGE_ECDHE_RSA:
case POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA:
usage = KU_DIGITAL_SIGNATURE;
break;
case POLARSSL_KEY_EXCHANGE_ECDH_RSA:
case POLARSSL_KEY_EXCHANGE_ECDH_ECDSA:
usage = KU_KEY_AGREEMENT;
break;
/* Don't use default: we want warnings when adding new values */
case POLARSSL_KEY_EXCHANGE_NONE:
case POLARSSL_KEY_EXCHANGE_PSK:
case POLARSSL_KEY_EXCHANGE_DHE_PSK:
case POLARSSL_KEY_EXCHANGE_ECDHE_PSK:
usage = 0;
}
}
else
{
/* Client auth: we only implement rsa_sign and ecdsa_sign for now */
usage = KU_DIGITAL_SIGNATURE;
}
if( x509_crt_check_key_usage( cert, usage ) != 0 )
return( -1 );
#else
((void) ciphersuite);
#endif /* POLARSSL_X509_CHECK_KEY_USAGE */
#if defined(POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE)
if( cert_endpoint == SSL_IS_SERVER )
{
ext_oid = OID_SERVER_AUTH;
ext_len = OID_SIZE( OID_SERVER_AUTH );
}
else
{
ext_oid = OID_CLIENT_AUTH;
ext_len = OID_SIZE( OID_CLIENT_AUTH );
}
if( x509_crt_check_extended_key_usage( cert, ext_oid, ext_len ) != 0 )
return( -1 );
#endif /* POLARSSL_X509_CHECK_EXTENDED_KEY_USAGE */
return( 0 );
}
#endif /* POLARSSL_X509_CRT_PARSE_C */
/*
* Convert version numbers to/from wire format
* and, for DTLS, to/from TLS equivalent.
*
* For TLS this is the identity.
* For DTLS, use one complement (v -> 255 - v, and then map as follows:
* 1.0 <-> 3.2 (DTLS 1.0 is based on TLS 1.1)
* 1.x <-> 3.x+1 for x != 0 (DTLS 1.2 based on TLS 1.2)
*/
void ssl_write_version( int major, int minor, int transport,
unsigned char ver[2] )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( transport == SSL_TRANSPORT_DATAGRAM )
{
if( minor == SSL_MINOR_VERSION_2 )
--minor; /* DTLS 1.0 stored as TLS 1.1 internally */
ver[0] = (unsigned char)( 255 - ( major - 2 ) );
ver[1] = (unsigned char)( 255 - ( minor - 1 ) );
}
else
#else
((void) transport);
#endif
{
ver[0] = (unsigned char) major;
ver[1] = (unsigned char) minor;
}
}
void ssl_read_version( int *major, int *minor, int transport,
const unsigned char ver[2] )
{
#if defined(POLARSSL_SSL_PROTO_DTLS)
if( transport == SSL_TRANSPORT_DATAGRAM )
{
*major = 255 - ver[0] + 2;
*minor = 255 - ver[1] + 1;
if( *minor == SSL_MINOR_VERSION_1 )
++*minor; /* DTLS 1.0 stored as TLS 1.1 internally */
}
else
#else
((void) transport);
#endif
{
*major = ver[0];
*minor = ver[1];
}
}
#endif /* POLARSSL_SSL_TLS_C */