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ddbb166041
mbedtls/library/ssl_cli.c
Manuel Pégourié-Gonnard d80532481a Fix levels of some debug messages 
Messages about returning an error code that will be propagated all the way up
to the user should always be level 1.
2015-12-08 09:55:44 +01:00

3391 lines
108 KiB
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/*
* SSLv3/TLSv1 client-side functions
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_SSL_CLI_C)
#include "mbedtls/debug.h"
#include "mbedtls/ssl.h"
#include "mbedtls/ssl_internal.h"
#include <string.h>
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
#include <stdint.h>
#if defined(MBEDTLS_HAVE_TIME)
#include <time.h>
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize( void *v, size_t n ) {
volatile unsigned char *p = v; while( n-- ) *p++ = 0;
}
#endif
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
static void ssl_write_hostname_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
size_t hostname_len;
*olen = 0;
if( ssl->hostname == NULL )
return;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding server name extension: %s",
ssl->hostname ) );
hostname_len = strlen( ssl->hostname );
if( end < p || (size_t)( end - p ) < hostname_len + 9 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
/*
* struct {
* NameType name_type;
* select (name_type) {
* case host_name: HostName;
* } name;
* } ServerName;
*
* enum {
* host_name(0), (255)
* } NameType;
*
* opaque HostName<1..2^16-1>;
*
* struct {
* ServerName server_name_list<1..2^16-1>
* } ServerNameList;
*/
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME ) & 0xFF );
*p++ = (unsigned char)( ( (hostname_len + 5) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( (hostname_len + 5) ) & 0xFF );
*p++ = (unsigned char)( ( (hostname_len + 3) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( (hostname_len + 3) ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME ) & 0xFF );
*p++ = (unsigned char)( ( hostname_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( hostname_len ) & 0xFF );
memcpy( p, ssl->hostname, hostname_len );
*olen = hostname_len + 9;
}
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_SSL_RENEGOTIATION)
static void ssl_write_renegotiation_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
if( ssl->renego_status != MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
return;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding renegotiation extension" ) );
if( end < p || (size_t)( end - p ) < 5 + ssl->verify_data_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
/*
* Secure renegotiation
*/
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO ) & 0xFF );
*p++ = 0x00;
*p++ = ( ssl->verify_data_len + 1 ) & 0xFF;
*p++ = ssl->verify_data_len & 0xFF;
memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
*olen = 5 + ssl->verify_data_len;
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/*
* Only if we handle at least one key exchange that needs signatures.
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
static void ssl_write_signature_algorithms_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
size_t sig_alg_len = 0;
const int *md;
#if defined(MBEDTLS_RSA_C) || defined(MBEDTLS_ECDSA_C)
unsigned char *sig_alg_list = buf + 6;
#endif
*olen = 0;
if( ssl->conf->max_minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 )
return;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding signature_algorithms extension" ) );
for( md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++ )
{
#if defined(MBEDTLS_ECDSA_C)
sig_alg_len += 2;
#endif
#if defined(MBEDTLS_RSA_C)
sig_alg_len += 2;
#endif
}
if( end < p || (size_t)( end - p ) < sig_alg_len + 6 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
/*
* Prepare signature_algorithms extension (TLS 1.2)
*/
sig_alg_len = 0;
for( md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++ )
{
#if defined(MBEDTLS_ECDSA_C)
sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg( *md );
sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_ECDSA;
#endif
#if defined(MBEDTLS_RSA_C)
sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg( *md );
sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_RSA;
#endif
}
/*
* enum {
* none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5),
* sha512(6), (255)
* } HashAlgorithm;
*
* enum { anonymous(0), rsa(1), dsa(2), ecdsa(3), (255) }
* SignatureAlgorithm;
*
* struct {
* HashAlgorithm hash;
* SignatureAlgorithm signature;
* } SignatureAndHashAlgorithm;
*
* SignatureAndHashAlgorithm
* supported_signature_algorithms<2..2^16-2>;
*/
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SIG_ALG >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SIG_ALG ) & 0xFF );
*p++ = (unsigned char)( ( ( sig_alg_len + 2 ) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ( sig_alg_len + 2 ) ) & 0xFF );
*p++ = (unsigned char)( ( sig_alg_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( sig_alg_len ) & 0xFF );
*olen = 6 + sig_alg_len;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static void ssl_write_supported_elliptic_curves_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
unsigned char *elliptic_curve_list = p + 6;
size_t elliptic_curve_len = 0;
const mbedtls_ecp_curve_info *info;
#if defined(MBEDTLS_ECP_C)
const mbedtls_ecp_group_id *grp_id;
#else
((void) ssl);
#endif
*olen = 0;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding supported_elliptic_curves extension" ) );
#if defined(MBEDTLS_ECP_C)
for( grp_id = ssl->conf->curve_list; *grp_id != MBEDTLS_ECP_DP_NONE; grp_id++ )
{
info = mbedtls_ecp_curve_info_from_grp_id( *grp_id );
#else
for( info = mbedtls_ecp_curve_list(); info->grp_id != MBEDTLS_ECP_DP_NONE; info++ )
{
#endif
elliptic_curve_len += 2;
}
if( end < p || (size_t)( end - p ) < 6 + elliptic_curve_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
elliptic_curve_len = 0;
#if defined(MBEDTLS_ECP_C)
for( grp_id = ssl->conf->curve_list; *grp_id != MBEDTLS_ECP_DP_NONE; grp_id++ )
{
info = mbedtls_ecp_curve_info_from_grp_id( *grp_id );
#else
for( info = mbedtls_ecp_curve_list(); info->grp_id != MBEDTLS_ECP_DP_NONE; info++ )
{
#endif
elliptic_curve_list[elliptic_curve_len++] = info->tls_id >> 8;
elliptic_curve_list[elliptic_curve_len++] = info->tls_id & 0xFF;
}
if( elliptic_curve_len == 0 )
return;
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES ) & 0xFF );
*p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) ) & 0xFF );
*p++ = (unsigned char)( ( ( elliptic_curve_len ) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ( elliptic_curve_len ) ) & 0xFF );
*olen = 6 + elliptic_curve_len;
}
static void ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding supported_point_formats extension" ) );
if( end < p || (size_t)( end - p ) < 6 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS ) & 0xFF );
*p++ = 0x00;
*p++ = 2;
*p++ = 1;
*p++ = MBEDTLS_ECP_PF_UNCOMPRESSED;
*olen = 6;
}
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static void ssl_write_ecjpake_kkpp_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
int ret;
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
size_t kkpp_len;
*olen = 0;
/* Skip costly extension if we can't use EC J-PAKE anyway */
if( mbedtls_ecjpake_check( &ssl->handshake->ecjpake_ctx ) != 0 )
return;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding ecjpake_kkpp extension" ) );
if( end - p < 4 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ECJPAKE_KKPP >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ECJPAKE_KKPP ) & 0xFF );
/*
* We may need to send ClientHello multiple times for Hello verification.
* We don't want to compute fresh values every time (both for performance
* and consistency reasons), so cache the extension content.
*/
if( ssl->handshake->ecjpake_cache == NULL ||
ssl->handshake->ecjpake_cache_len == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "generating new ecjpake parameters" ) );
ret = mbedtls_ecjpake_write_round_one( &ssl->handshake->ecjpake_ctx,
p + 2, end - p - 2, &kkpp_len,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1 , "mbedtls_ecjpake_write_round_one", ret );
return;
}
ssl->handshake->ecjpake_cache = mbedtls_calloc( 1, kkpp_len );
if( ssl->handshake->ecjpake_cache == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "allocation failed" ) );
return;
}
memcpy( ssl->handshake->ecjpake_cache, p + 2, kkpp_len );
ssl->handshake->ecjpake_cache_len = kkpp_len;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "re-using cached ecjpake parameters" ) );
kkpp_len = ssl->handshake->ecjpake_cache_len;
if( (size_t)( end - p - 2 ) < kkpp_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
memcpy( p + 2, ssl->handshake->ecjpake_cache, kkpp_len );
}
*p++ = (unsigned char)( ( kkpp_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( kkpp_len ) & 0xFF );
*olen = kkpp_len + 4;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
static void ssl_write_max_fragment_length_ext( mbedtls_ssl_context *ssl,
unsigned char *buf,
size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
if( ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE ) {
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding max_fragment_length extension" ) );
if( end < p || (size_t)( end - p ) < 5 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH ) & 0xFF );
*p++ = 0x00;
*p++ = 1;
*p++ = ssl->conf->mfl_code;
*olen = 5;
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
static void ssl_write_truncated_hmac_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding truncated_hmac extension" ) );
if( end < p || (size_t)( end - p ) < 4 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC ) & 0xFF );
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
static void ssl_write_encrypt_then_mac_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
if( ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED ||
ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding encrypt_then_mac "
"extension" ) );
if( end < p || (size_t)( end - p ) < 4 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC ) & 0xFF );
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
static void ssl_write_extended_ms_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
*olen = 0;
if( ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED ||
ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding extended_master_secret "
"extension" ) );
if( end < p || (size_t)( end - p ) < 4 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET ) & 0xFF );
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
}
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
static void ssl_write_session_ticket_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
size_t tlen = ssl->session_negotiate->ticket_len;
*olen = 0;
if( ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding session ticket extension" ) );
if( end < p || (size_t)( end - p ) < 4 + tlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET ) & 0xFF );
*p++ = (unsigned char)( ( tlen >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( tlen ) & 0xFF );
*olen = 4;
if( ssl->session_negotiate->ticket == NULL || tlen == 0 )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "sending session ticket of length %d", tlen ) );
memcpy( p, ssl->session_negotiate->ticket, tlen );
*olen += tlen;
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_SSL_ALPN)
static void ssl_write_alpn_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
unsigned char *p = buf;
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_MAX_CONTENT_LEN;
size_t alpnlen = 0;
const char **cur;
*olen = 0;
if( ssl->conf->alpn_list == NULL )
{
return;
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding alpn extension" ) );
for( cur = ssl->conf->alpn_list; *cur != NULL; cur++ )
alpnlen += (unsigned char)( strlen( *cur ) & 0xFF ) + 1;
if( end < p || (size_t)( end - p ) < 6 + alpnlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
return;
}
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN ) & 0xFF );
/*
* opaque ProtocolName<1..2^8-1>;
*
* struct {
* ProtocolName protocol_name_list<2..2^16-1>
* } ProtocolNameList;
*/
/* Skip writing extension and list length for now */
p += 4;
for( cur = ssl->conf->alpn_list; *cur != NULL; cur++ )
{
*p = (unsigned char)( strlen( *cur ) & 0xFF );
memcpy( p + 1, *cur, *p );
p += 1 + *p;
}
*olen = p - buf;
/* List length = olen - 2 (ext_type) - 2 (ext_len) - 2 (list_len) */
buf[4] = (unsigned char)( ( ( *olen - 6 ) >> 8 ) & 0xFF );
buf[5] = (unsigned char)( ( ( *olen - 6 ) ) & 0xFF );
/* Extension length = olen - 2 (ext_type) - 2 (ext_len) */
buf[2] = (unsigned char)( ( ( *olen - 4 ) >> 8 ) & 0xFF );
buf[3] = (unsigned char)( ( ( *olen - 4 ) ) & 0xFF );
}
#endif /* MBEDTLS_SSL_ALPN */
/*
* Generate random bytes for ClientHello
*/
static int ssl_generate_random( mbedtls_ssl_context *ssl )
{
int ret;
unsigned char *p = ssl->handshake->randbytes;
#if defined(MBEDTLS_HAVE_TIME)
time_t t;
#endif
/*
* When responding to a verify request, MUST reuse random (RFC 6347 4.2.1)
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->verify_cookie != NULL )
{
return( 0 );
}
#endif
#if defined(MBEDTLS_HAVE_TIME)
t = time( NULL );
*p++ = (unsigned char)( t >> 24 );
*p++ = (unsigned char)( t >> 16 );
*p++ = (unsigned char)( t >> 8 );
*p++ = (unsigned char)( t );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, current time: %lu", t ) );
#else
if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p, 4 ) ) != 0 )
return( ret );
p += 4;
#endif /* MBEDTLS_HAVE_TIME */
if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p, 28 ) ) != 0 )
return( ret );
return( 0 );
}
static int ssl_write_client_hello( mbedtls_ssl_context *ssl )
{
int ret;
size_t i, n, olen, ext_len = 0;
unsigned char *buf;
unsigned char *p, *q;
unsigned char offer_compress;
const int *ciphersuites;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write client hello" ) );
if( ssl->conf->f_rng == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no RNG provided") );
return( MBEDTLS_ERR_SSL_NO_RNG );
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE )
#endif
{
ssl->major_ver = ssl->conf->min_major_ver;
ssl->minor_ver = ssl->conf->min_minor_ver;
}
if( ssl->conf->max_major_ver == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "configured max major version is invalid, "
"consider using mbedtls_ssl_config_defaults()" ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
/*
* 0 . 0 handshake type
* 1 . 3 handshake length
* 4 . 5 highest version supported
* 6 . 9 current UNIX time
* 10 . 37 random bytes
*/
buf = ssl->out_msg;
p = buf + 4;
mbedtls_ssl_write_version( ssl->conf->max_major_ver, ssl->conf->max_minor_ver,
ssl->conf->transport, p );
p += 2;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, max version: [%d:%d]",
buf[4], buf[5] ) );
if( ( ret = ssl_generate_random( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_generate_random", ret );
return( ret );
}
memcpy( p, ssl->handshake->randbytes, 32 );
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, random bytes", p, 32 );
p += 32;
/*
* 38 . 38 session id length
* 39 . 39+n session id
* 39+n . 39+n DTLS only: cookie length (1 byte)
* 40+n . .. DTSL only: cookie
* .. . .. ciphersuitelist length (2 bytes)
* .. . .. ciphersuitelist
* .. . .. compression methods length (1 byte)
* .. . .. compression methods
* .. . .. extensions length (2 bytes)
* .. . .. extensions
*/
n = ssl->session_negotiate->id_len;
if( n < 16 || n > 32 ||
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ||
#endif
ssl->handshake->resume == 0 )
{
n = 0;
}
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
/*
* RFC 5077 section 3.4: "When presenting a ticket, the client MAY
* generate and include a Session ID in the TLS ClientHello."
*/
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE )
#endif
{
if( ssl->session_negotiate->ticket != NULL &&
ssl->session_negotiate->ticket_len != 0 )
{
ret = ssl->conf->f_rng( ssl->conf->p_rng, ssl->session_negotiate->id, 32 );
if( ret != 0 )
return( ret );
ssl->session_negotiate->id_len = n = 32;
}
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
*p++ = (unsigned char) n;
for( i = 0; i < n; i++ )
*p++ = ssl->session_negotiate->id[i];
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %d", n ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, session id", buf + 39, n );
/*
* DTLS cookie
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
if( ssl->handshake->verify_cookie == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no verify cookie to send" ) );
*p++ = 0;
}
else
{
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, cookie",
ssl->handshake->verify_cookie,
ssl->handshake->verify_cookie_len );
*p++ = ssl->handshake->verify_cookie_len;
memcpy( p, ssl->handshake->verify_cookie,
ssl->handshake->verify_cookie_len );
p += ssl->handshake->verify_cookie_len;
}
}
#endif
/*
* Ciphersuite list
*/
ciphersuites = ssl->conf->ciphersuite_list[ssl->minor_ver];
/* Skip writing ciphersuite length for now */
n = 0;
q = p;
p += 2;
for( i = 0; ciphersuites[i] != 0; i++ )
{
ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( ciphersuites[i] );
if( ciphersuite_info == NULL )
continue;
if( ciphersuite_info->min_minor_ver > ssl->conf->max_minor_ver ||
ciphersuite_info->max_minor_ver < ssl->conf->min_minor_ver )
continue;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
( ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_NODTLS ) )
continue;
#endif
#if defined(MBEDTLS_ARC4_C)
if( ssl->conf->arc4_disabled == MBEDTLS_SSL_ARC4_DISABLED &&
ciphersuite_info->cipher == MBEDTLS_CIPHER_ARC4_128 )
continue;
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE &&
mbedtls_ecjpake_check( &ssl->handshake->ecjpake_ctx ) != 0 )
continue;
#endif
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, add ciphersuite: %04x",
ciphersuites[i] ) );
n++;
*p++ = (unsigned char)( ciphersuites[i] >> 8 );
*p++ = (unsigned char)( ciphersuites[i] );
}
/*
* Add TLS_EMPTY_RENEGOTIATION_INFO_SCSV
*/
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE )
#endif
{
*p++ = (unsigned char)( MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO >> 8 );
*p++ = (unsigned char)( MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO );
n++;
}
/* Some versions of OpenSSL don't handle it correctly if not at end */
#if defined(MBEDTLS_SSL_FALLBACK_SCSV)
if( ssl->conf->fallback == MBEDTLS_SSL_IS_FALLBACK )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "adding FALLBACK_SCSV" ) );
*p++ = (unsigned char)( MBEDTLS_SSL_FALLBACK_SCSV_VALUE >> 8 );
*p++ = (unsigned char)( MBEDTLS_SSL_FALLBACK_SCSV_VALUE );
n++;
}
#endif
*q++ = (unsigned char)( n >> 7 );
*q++ = (unsigned char)( n << 1 );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, got %d ciphersuites", n ) );
#if defined(MBEDTLS_ZLIB_SUPPORT)
offer_compress = 1;
#else
offer_compress = 0;
#endif
/*
* We don't support compression with DTLS right now: is many records come
* in the same datagram, uncompressing one could overwrite the next one.
* We don't want to add complexity for handling that case unless there is
* an actual need for it.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
offer_compress = 0;
#endif
if( offer_compress )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress len.: %d", 2 ) );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress alg.: %d %d",
MBEDTLS_SSL_COMPRESS_DEFLATE, MBEDTLS_SSL_COMPRESS_NULL ) );
*p++ = 2;
*p++ = MBEDTLS_SSL_COMPRESS_DEFLATE;
*p++ = MBEDTLS_SSL_COMPRESS_NULL;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress len.: %d", 1 ) );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress alg.: %d",
MBEDTLS_SSL_COMPRESS_NULL ) );
*p++ = 1;
*p++ = MBEDTLS_SSL_COMPRESS_NULL;
}
// First write extensions, then the total length
//
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
ssl_write_hostname_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
ssl_write_signature_algorithms_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
ssl_write_supported_elliptic_curves_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
ssl_write_supported_point_formats_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
ssl_write_ecjpake_kkpp_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
ssl_write_truncated_hmac_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
ssl_write_encrypt_then_mac_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
ssl_write_extended_ms_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_ALPN)
ssl_write_alpn_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
ssl_write_session_ticket_ext( ssl, p + 2 + ext_len, &olen );
ext_len += olen;
#endif
/* olen unused if all extensions are disabled */
((void) olen);
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %d",
ext_len ) );
if( ext_len > 0 )
{
*p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ext_len ) & 0xFF );
p += ext_len;
}
ssl->out_msglen = p - buf;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_HELLO;
ssl->state++;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
mbedtls_ssl_send_flight_completed( ssl );
#endif
if( ( ret = mbedtls_ssl_write_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write client hello" ) );
return( 0 );
}
static int ssl_parse_renegotiation_info( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
int ret;
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE )
{
/* Check verify-data in constant-time. The length OTOH is no secret */
if( len != 1 + ssl->verify_data_len * 2 ||
buf[0] != ssl->verify_data_len * 2 ||
mbedtls_ssl_safer_memcmp( buf + 1,
ssl->own_verify_data, ssl->verify_data_len ) != 0 ||
mbedtls_ssl_safer_memcmp( buf + 1 + ssl->verify_data_len,
ssl->peer_verify_data, ssl->verify_data_len ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-matching renegotiation info" ) );
if( ( ret = mbedtls_ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
}
else
#endif /* MBEDTLS_SSL_RENEGOTIATION */
{
if( len != 1 || buf[0] != 0x00 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-zero length renegotiation info" ) );
if( ( ret = mbedtls_ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION;
}
return( 0 );
}
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
static int ssl_parse_max_fragment_length_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
/*
* server should use the extension only if we did,
* and if so the server's value should match ours (and len is always 1)
*/
if( ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE ||
len != 1 ||
buf[0] != ssl->conf->mfl_code )
{
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
return( 0 );
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
static int ssl_parse_truncated_hmac_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED ||
len != 0 )
{
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
((void) buf);
ssl->session_negotiate->trunc_hmac = MBEDTLS_SSL_TRUNC_HMAC_ENABLED;
return( 0 );
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
static int ssl_parse_encrypt_then_mac_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
if( ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED ||
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
len != 0 )
{
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
((void) buf);
ssl->session_negotiate->encrypt_then_mac = MBEDTLS_SSL_ETM_ENABLED;
return( 0 );
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
static int ssl_parse_extended_ms_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
if( ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED ||
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
len != 0 )
{
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
((void) buf);
ssl->handshake->extended_ms = MBEDTLS_SSL_EXTENDED_MS_ENABLED;
return( 0 );
}
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
static int ssl_parse_session_ticket_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
if( ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED ||
len != 0 )
{
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
((void) buf);
ssl->handshake->new_session_ticket = 1;
return( 0 );
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static int ssl_parse_supported_point_formats_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
size_t list_size;
const unsigned char *p;
list_size = buf[0];
if( list_size + 1 != len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
p = buf + 1;
while( list_size > 0 )
{
if( p[0] == MBEDTLS_ECP_PF_UNCOMPRESSED ||
p[0] == MBEDTLS_ECP_PF_COMPRESSED )
{
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C)
ssl->handshake->ecdh_ctx.point_format = p[0];
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
ssl->handshake->ecjpake_ctx.point_format = p[0];
#endif
MBEDTLS_SSL_DEBUG_MSG( 4, ( "point format selected: %d", p[0] ) );
return( 0 );
}
list_size--;
p++;
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no point format in common" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
static int ssl_parse_ecjpake_kkpp( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
{
int ret;
if( ssl->transform_negotiate->ciphersuite_info->key_exchange !=
MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip ecjpake kkpp extension" ) );
return( 0 );
}
/* If we got here, we no longer need our cached extension */
mbedtls_free( ssl->handshake->ecjpake_cache );
ssl->handshake->ecjpake_cache = NULL;
ssl->handshake->ecjpake_cache_len = 0;
if( ( ret = mbedtls_ecjpake_read_round_one( &ssl->handshake->ecjpake_ctx,
buf, len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_read_round_one", ret );
return( ret );
}
return( 0 );
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_ALPN)
static int ssl_parse_alpn_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
size_t list_len, name_len;
const char **p;
/* If we didn't send it, the server shouldn't send it */
if( ssl->conf->alpn_list == NULL )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
/*
* opaque ProtocolName<1..2^8-1>;
*
* struct {
* ProtocolName protocol_name_list<2..2^16-1>
* } ProtocolNameList;
*
* the "ProtocolNameList" MUST contain exactly one "ProtocolName"
*/
/* Min length is 2 (list_len) + 1 (name_len) + 1 (name) */
if( len < 4 )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
list_len = ( buf[0] << 8 ) | buf[1];
if( list_len != len - 2 )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
name_len = buf[2];
if( name_len != list_len - 1 )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
/* Check that the server chosen protocol was in our list and save it */
for( p = ssl->conf->alpn_list; *p != NULL; p++ )
{
if( name_len == strlen( *p ) &&
memcmp( buf + 3, *p, name_len ) == 0 )
{
ssl->alpn_chosen = *p;
return( 0 );
}
}
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
#endif /* MBEDTLS_SSL_ALPN */
/*
* Parse HelloVerifyRequest. Only called after verifying the HS type.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
static int ssl_parse_hello_verify_request( mbedtls_ssl_context *ssl )
{
const unsigned char *p = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
int major_ver, minor_ver;
unsigned char cookie_len;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse hello verify request" ) );
/*
* struct {
* ProtocolVersion server_version;
* opaque cookie<0..2^8-1>;
* } HelloVerifyRequest;
*/
MBEDTLS_SSL_DEBUG_BUF( 3, "server version", p, 2 );
mbedtls_ssl_read_version( &major_ver, &minor_ver, ssl->conf->transport, p );
p += 2;
/*
* Since the RFC is not clear on this point, accept DTLS 1.0 (TLS 1.1)
* even is lower than our min version.
*/
if( major_ver < MBEDTLS_SSL_MAJOR_VERSION_3 ||
minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 ||
major_ver > ssl->conf->max_major_ver ||
minor_ver > ssl->conf->max_minor_ver )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server version" ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION );
return( MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION );
}
cookie_len = *p++;
MBEDTLS_SSL_DEBUG_BUF( 3, "cookie", p, cookie_len );
mbedtls_free( ssl->handshake->verify_cookie );
ssl->handshake->verify_cookie = mbedtls_calloc( 1, cookie_len );
if( ssl->handshake->verify_cookie == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc failed (%d bytes)", cookie_len ) );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
memcpy( ssl->handshake->verify_cookie, p, cookie_len );
ssl->handshake->verify_cookie_len = cookie_len;
/* Start over at ClientHello */
ssl->state = MBEDTLS_SSL_CLIENT_HELLO;
mbedtls_ssl_reset_checksum( ssl );
mbedtls_ssl_recv_flight_completed( ssl );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse hello verify request" ) );
return( 0 );
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static int ssl_parse_server_hello( mbedtls_ssl_context *ssl )
{
int ret, i;
size_t n;
size_t ext_len;
unsigned char *buf, *ext;
unsigned char comp;
#if defined(MBEDTLS_ZLIB_SUPPORT)
int accept_comp;
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
int renegotiation_info_seen = 0;
#endif
int handshake_failure = 0;
const mbedtls_ssl_ciphersuite_t *suite_info;
#if defined(MBEDTLS_DEBUG_C)
uint32_t t;
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server hello" ) );
buf = ssl->in_msg;
if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS )
{
ssl->renego_records_seen++;
if( ssl->conf->renego_max_records >= 0 &&
ssl->renego_records_seen > ssl->conf->renego_max_records )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "renegotiation requested, "
"but not honored by server" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-handshake message during renego" ) );
return( MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO );
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
if( buf[0] == MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "received hello verify request" ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello" ) );
return( ssl_parse_hello_verify_request( ssl ) );
}
else
{
/* We made it through the verification process */
mbedtls_free( ssl->handshake->verify_cookie );
ssl->handshake->verify_cookie = NULL;
ssl->handshake->verify_cookie_len = 0;
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
if( ssl->in_hslen < 38 + mbedtls_ssl_hs_hdr_len( ssl ) ||
buf[0] != MBEDTLS_SSL_HS_SERVER_HELLO )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
/*
* 0 . 1 server_version
* 2 . 33 random (maybe including 4 bytes of Unix time)
* 34 . 34 session_id length = n
* 35 . 34+n session_id
* 35+n . 36+n cipher_suite
* 37+n . 37+n compression_method
*
* 38+n . 39+n extensions length (optional)
* 40+n . .. extensions
*/
buf += mbedtls_ssl_hs_hdr_len( ssl );
MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, version", buf + 0, 2 );
mbedtls_ssl_read_version( &ssl->major_ver, &ssl->minor_ver,
ssl->conf->transport, buf + 0 );
if( ssl->major_ver < ssl->conf->min_major_ver ||
ssl->minor_ver < ssl->conf->min_minor_ver ||
ssl->major_ver > ssl->conf->max_major_ver ||
ssl->minor_ver > ssl->conf->max_minor_ver )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server version out of bounds - "
" min: [%d:%d], server: [%d:%d], max: [%d:%d]",
ssl->conf->min_major_ver, ssl->conf->min_minor_ver,
ssl->major_ver, ssl->minor_ver,
ssl->conf->max_major_ver, ssl->conf->max_minor_ver ) );
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION );
return( MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION );
}
#if defined(MBEDTLS_DEBUG_C)
t = ( (uint32_t) buf[2] << 24 )
| ( (uint32_t) buf[3] << 16 )
| ( (uint32_t) buf[4] << 8 )
| ( (uint32_t) buf[5] );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu", t ) );
#endif
memcpy( ssl->handshake->randbytes + 32, buf + 2, 32 );
n = buf[34];
MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 2, 32 );
if( n > 32 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
if( ssl->in_hslen > mbedtls_ssl_hs_hdr_len( ssl ) + 39 + n )
{
ext_len = ( ( buf[38 + n] << 8 )
| ( buf[39 + n] ) );
if( ( ext_len > 0 && ext_len < 4 ) ||
ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) + 40 + n + ext_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
}
else if( ssl->in_hslen == mbedtls_ssl_hs_hdr_len( ssl ) + 38 + n )
{
ext_len = 0;
}
else
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
/* ciphersuite (used later) */
i = ( buf[35 + n] << 8 ) | buf[36 + n];
/*
* Read and check compression
*/
comp = buf[37 + n];
#if defined(MBEDTLS_ZLIB_SUPPORT)
/* See comments in ssl_write_client_hello() */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
accept_comp = 0;
else
#endif
accept_comp = 1;
if( comp != MBEDTLS_SSL_COMPRESS_NULL &&
( comp != MBEDTLS_SSL_COMPRESS_DEFLATE || accept_comp == 0 ) )
#else /* MBEDTLS_ZLIB_SUPPORT */
if( comp != MBEDTLS_SSL_COMPRESS_NULL )
#endif/* MBEDTLS_ZLIB_SUPPORT */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server hello, bad compression: %d", comp ) );
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
/*
* Initialize update checksum functions
*/
ssl->transform_negotiate->ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( i );
if( ssl->transform_negotiate->ciphersuite_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "ciphersuite info for %04x not found", i ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
mbedtls_ssl_optimize_checksum( ssl, ssl->transform_negotiate->ciphersuite_info );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, session id", buf + 35, n );
/*
* Check if the session can be resumed
*/
if( ssl->handshake->resume == 0 || n == 0 ||
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ||
#endif
ssl->session_negotiate->ciphersuite != i ||
ssl->session_negotiate->compression != comp ||
ssl->session_negotiate->id_len != n ||
memcmp( ssl->session_negotiate->id, buf + 35, n ) != 0 )
{
ssl->state++;
ssl->handshake->resume = 0;
#if defined(MBEDTLS_HAVE_TIME)
ssl->session_negotiate->start = time( NULL );
#endif
ssl->session_negotiate->ciphersuite = i;
ssl->session_negotiate->compression = comp;
ssl->session_negotiate->id_len = n;
memcpy( ssl->session_negotiate->id, buf + 35, n );
}
else
{
ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC;
if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret );
return( ret );
}
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "%s session has been resumed",
ssl->handshake->resume ? "a" : "no" ) );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %04x", i ) );
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d", buf[37 + n] ) );
suite_info = mbedtls_ssl_ciphersuite_from_id( ssl->session_negotiate->ciphersuite );
if( suite_info == NULL
#if defined(MBEDTLS_ARC4_C)
|| ( ssl->conf->arc4_disabled &&
suite_info->cipher == MBEDTLS_CIPHER_ARC4_128 )
#endif
)
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %s", suite_info->name ) );
i = 0;
while( 1 )
{
if( ssl->conf->ciphersuite_list[ssl->minor_ver][i] == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
if( ssl->conf->ciphersuite_list[ssl->minor_ver][i++] ==
ssl->session_negotiate->ciphersuite )
{
break;
}
}
if( comp != MBEDTLS_SSL_COMPRESS_NULL
#if defined(MBEDTLS_ZLIB_SUPPORT)
&& comp != MBEDTLS_SSL_COMPRESS_DEFLATE
#endif
)
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
ssl->session_negotiate->compression = comp;
ext = buf + 40 + n;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "server hello, total extension length: %d", ext_len ) );
while( ext_len )
{
unsigned int ext_id = ( ( ext[0] << 8 )
| ( ext[1] ) );
unsigned int ext_size = ( ( ext[2] << 8 )
| ( ext[3] ) );
if( ext_size + 4 > ext_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
switch( ext_id )
{
case MBEDTLS_TLS_EXT_RENEGOTIATION_INFO:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found renegotiation extension" ) );
#if defined(MBEDTLS_SSL_RENEGOTIATION)
renegotiation_info_seen = 1;
#endif
if( ( ret = ssl_parse_renegotiation_info( ssl, ext + 4,
ext_size ) ) != 0 )
return( ret );
break;
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
case MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found max_fragment_length extension" ) );
if( ( ret = ssl_parse_max_fragment_length_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
case MBEDTLS_TLS_EXT_TRUNCATED_HMAC:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found truncated_hmac extension" ) );
if( ( ret = ssl_parse_truncated_hmac_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
case MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found encrypt_then_mac extension" ) );
if( ( ret = ssl_parse_encrypt_then_mac_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
case MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found extended_master_secret extension" ) );
if( ( ret = ssl_parse_extended_ms_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
case MBEDTLS_TLS_EXT_SESSION_TICKET:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found session_ticket extension" ) );
if( ( ret = ssl_parse_session_ticket_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
case MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found supported_point_formats extension" ) );
if( ( ret = ssl_parse_supported_point_formats_ext( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
case MBEDTLS_TLS_EXT_ECJPAKE_KKPP:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found ecjpake_kkpp extension" ) );
if( ( ret = ssl_parse_ecjpake_kkpp( ssl,
ext + 4, ext_size ) ) != 0 )
{
return( ret );
}
break;
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_ALPN)
case MBEDTLS_TLS_EXT_ALPN:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found alpn extension" ) );
if( ( ret = ssl_parse_alpn_ext( ssl, ext + 4, ext_size ) ) != 0 )
return( ret );
break;
#endif /* MBEDTLS_SSL_ALPN */
default:
MBEDTLS_SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
ext_id ) );
}
ext_len -= 4 + ext_size;
ext += 4 + ext_size;
if( ext_len > 0 && ext_len < 4 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
}
/*
* Renegotiation security checks
*/
if( ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
ssl->conf->allow_legacy_renegotiation == MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "legacy renegotiation, breaking off handshake" ) );
handshake_failure = 1;
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_SECURE_RENEGOTIATION &&
renegotiation_info_seen == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "renegotiation_info extension missing (secure)" ) );
handshake_failure = 1;
}
else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
ssl->conf->allow_legacy_renegotiation == MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "legacy renegotiation not allowed" ) );
handshake_failure = 1;
}
else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
renegotiation_info_seen == 1 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "renegotiation_info extension present (legacy)" ) );
handshake_failure = 1;
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
if( handshake_failure == 1 )
{
if( ( ret = mbedtls_ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
return( ret );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello" ) );
return( 0 );
}
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
static int ssl_parse_server_dh_params( mbedtls_ssl_context *ssl, unsigned char **p,
unsigned char *end )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
/*
* Ephemeral DH parameters:
*
* struct {
* opaque dh_p<1..2^16-1>;
* opaque dh_g<1..2^16-1>;
* opaque dh_Ys<1..2^16-1>;
* } ServerDHParams;
*/
if( ( ret = mbedtls_dhm_read_params( &ssl->handshake->dhm_ctx, p, end ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 2, ( "mbedtls_dhm_read_params" ), ret );
return( ret );
}
if( ssl->handshake->dhm_ctx.len * 8 < ssl->conf->dhm_min_bitlen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "DHM prime too short: %d < %d",
ssl->handshake->dhm_ctx.len * 8,
ssl->conf->dhm_min_bitlen ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: P ", &ssl->handshake->dhm_ctx.P );
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: G ", &ssl->handshake->dhm_ctx.G );
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: GY", &ssl->handshake->dhm_ctx.GY );
return( ret );
}
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
static int ssl_check_server_ecdh_params( const mbedtls_ssl_context *ssl )
{
const mbedtls_ecp_curve_info *curve_info;
curve_info = mbedtls_ecp_curve_info_from_grp_id( ssl->handshake->ecdh_ctx.grp.id );
if( curve_info == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "ECDH curve: %s", curve_info->name ) );
#if defined(MBEDTLS_ECP_C)
if( mbedtls_ssl_check_curve( ssl, ssl->handshake->ecdh_ctx.grp.id ) != 0 )
#else
if( ssl->handshake->ecdh_ctx.grp.nbits < 163 ||
ssl->handshake->ecdh_ctx.grp.nbits > 521 )
#endif
return( -1 );
MBEDTLS_SSL_DEBUG_ECP( 3, "ECDH: Qp", &ssl->handshake->ecdh_ctx.Qp );
return( 0 );
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
static int ssl_parse_server_ecdh_params( mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
/*
* Ephemeral ECDH parameters:
*
* struct {
* ECParameters curve_params;
* ECPoint public;
* } ServerECDHParams;
*/
if( ( ret = mbedtls_ecdh_read_params( &ssl->handshake->ecdh_ctx,
(const unsigned char **) p, end ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_read_params" ), ret );
return( ret );
}
if( ssl_check_server_ecdh_params( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message (ECDHE curve)" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
return( ret );
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
static int ssl_parse_server_psk_hint( mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
size_t len;
((void) ssl);
/*
* PSK parameters:
*
* opaque psk_identity_hint<0..2^16-1>;
*/
len = (*p)[0] << 8 | (*p)[1];
*p += 2;
if( (*p) + len > end )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message (psk_identity_hint length)" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
// TODO: Retrieve PSK identity hint and callback to app
//
*p += len;
ret = 0;
return( ret );
}
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
/*
* Generate a pre-master secret and encrypt it with the server's RSA key
*/
static int ssl_write_encrypted_pms( mbedtls_ssl_context *ssl,
size_t offset, size_t *olen,
size_t pms_offset )
{
int ret;
size_t len_bytes = ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ? 0 : 2;
unsigned char *p = ssl->handshake->premaster + pms_offset;
if( offset + len_bytes > MBEDTLS_SSL_MAX_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small for encrypted pms" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
/*
* Generate (part of) the pre-master as
* struct {
* ProtocolVersion client_version;
* opaque random[46];
* } PreMasterSecret;
*/
mbedtls_ssl_write_version( ssl->conf->max_major_ver, ssl->conf->max_minor_ver,
ssl->conf->transport, p );
if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p + 2, 46 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "f_rng", ret );
return( ret );
}
ssl->handshake->pmslen = 48;
if( ssl->session_negotiate->peer_cert == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "certificate required" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/*
* Now write it out, encrypted
*/
if( ! mbedtls_pk_can_do( &ssl->session_negotiate->peer_cert->pk,
MBEDTLS_PK_RSA ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "certificate key type mismatch" ) );
return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH );
}
if( ( ret = mbedtls_pk_encrypt( &ssl->session_negotiate->peer_cert->pk,
p, ssl->handshake->pmslen,
ssl->out_msg + offset + len_bytes, olen,
MBEDTLS_SSL_MAX_CONTENT_LEN - offset - len_bytes,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_rsa_pkcs1_encrypt", ret );
return( ret );
}
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( len_bytes == 2 )
{
ssl->out_msg[offset+0] = (unsigned char)( *olen >> 8 );
ssl->out_msg[offset+1] = (unsigned char)( *olen );
*olen += 2;
}
#endif
return( 0 );
}
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
static int ssl_parse_signature_algorithm( mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end,
mbedtls_md_type_t *md_alg,
mbedtls_pk_type_t *pk_alg )
{
((void) ssl);
*md_alg = MBEDTLS_MD_NONE;
*pk_alg = MBEDTLS_PK_NONE;
/* Only in TLS 1.2 */
if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 )
{
return( 0 );
}
if( (*p) + 2 > end )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
/*
* Get hash algorithm
*/
if( ( *md_alg = mbedtls_ssl_md_alg_from_hash( (*p)[0] ) ) == MBEDTLS_MD_NONE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "Server used unsupported "
"HashAlgorithm %d", *(p)[0] ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
/*
* Get signature algorithm
*/
if( ( *pk_alg = mbedtls_ssl_pk_alg_from_sig( (*p)[1] ) ) == MBEDTLS_PK_NONE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server used unsupported "
"SignatureAlgorithm %d", (*p)[1] ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
/*
* Check if the hash is acceptable
*/
if( mbedtls_ssl_check_sig_hash( ssl, *md_alg ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server used HashAlgorithm "
"that was not offered" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Server used SignatureAlgorithm %d", (*p)[1] ) );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "Server used HashAlgorithm %d", (*p)[0] ) );
*p += 2;
return( 0 );
}
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
static int ssl_get_ecdh_params_from_cert( mbedtls_ssl_context *ssl )
{
int ret;
const mbedtls_ecp_keypair *peer_key;
if( ssl->session_negotiate->peer_cert == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "certificate required" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
if( ! mbedtls_pk_can_do( &ssl->session_negotiate->peer_cert->pk,
MBEDTLS_PK_ECKEY ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server key not ECDH capable" ) );
return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH );
}
peer_key = mbedtls_pk_ec( ssl->session_negotiate->peer_cert->pk );
if( ( ret = mbedtls_ecdh_get_params( &ssl->handshake->ecdh_ctx, peer_key,
MBEDTLS_ECDH_THEIRS ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_get_params" ), ret );
return( ret );
}
if( ssl_check_server_ecdh_params( ssl ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server certificate (ECDH curve)" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE );
}
return( ret );
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
static int ssl_parse_server_key_exchange( mbedtls_ssl_context *ssl )
{
int ret;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
unsigned char *p, *end;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server key exchange" ) );
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) );
ssl->state++;
return( 0 );
}
((void) p);
((void) end);
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA )
{
if( ( ret = ssl_get_ecdh_params_from_cert( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_get_ecdh_params_from_cert", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) );
ssl->state++;
return( 0 );
}
((void) p);
((void) end);
#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/*
* ServerKeyExchange may be skipped with PSK and RSA-PSK when the server
* doesn't use a psk_identity_hint
*/
if( ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE )
{
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
{
ssl->record_read = 1;
goto exit;
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
p = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
end = ssl->in_msg + ssl->in_hslen;
MBEDTLS_SSL_DEBUG_BUF( 3, "server key exchange", p, end - p );
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
if( ssl_parse_server_psk_hint( ssl, &p, end ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
} /* FALLTROUGH */
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
; /* nothing more to do */
else
#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK )
{
if( ssl_parse_server_dh_params( ssl, &p, end ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA )
{
if( ssl_parse_server_ecdh_params( ssl, &p, end ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
ret = mbedtls_ecjpake_read_round_two( &ssl->handshake->ecjpake_ctx,
p, end - p );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_read_round_two", ret );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA )
{
size_t sig_len, hashlen;
unsigned char hash[64];
mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE;
mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
unsigned char *params = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
size_t params_len = p - params;
/*
* Handle the digitally-signed structure
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
if( ssl_parse_signature_algorithm( ssl, &p, end,
&md_alg, &pk_alg ) != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
if( pk_alg != mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 )
{
pk_alg = mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info );
/* Default hash for ECDSA is SHA-1 */
if( pk_alg == MBEDTLS_PK_ECDSA && md_alg == MBEDTLS_MD_NONE )
md_alg = MBEDTLS_MD_SHA1;
}
else
#endif
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
/*
* Read signature
*/
sig_len = ( p[0] << 8 ) | p[1];
p += 2;
if( end != p + sig_len )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
}
MBEDTLS_SSL_DEBUG_BUF( 3, "signature", p, sig_len );
/*
* Compute the hash that has been signed
*/
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( md_alg == MBEDTLS_MD_NONE )
{
mbedtls_md5_context mbedtls_md5;
mbedtls_sha1_context mbedtls_sha1;
mbedtls_md5_init( &mbedtls_md5 );
mbedtls_sha1_init( &mbedtls_sha1 );
hashlen = 36;
/*
* digitally-signed struct {
* opaque md5_hash[16];
* opaque sha_hash[20];
* };
*
* md5_hash
* MD5(ClientHello.random + ServerHello.random
* + ServerParams);
* sha_hash
* SHA(ClientHello.random + ServerHello.random
* + ServerParams);
*/
mbedtls_md5_starts( &mbedtls_md5 );
mbedtls_md5_update( &mbedtls_md5, ssl->handshake->randbytes, 64 );
mbedtls_md5_update( &mbedtls_md5, params, params_len );
mbedtls_md5_finish( &mbedtls_md5, hash );
mbedtls_sha1_starts( &mbedtls_sha1 );
mbedtls_sha1_update( &mbedtls_sha1, ssl->handshake->randbytes, 64 );
mbedtls_sha1_update( &mbedtls_sha1, params, params_len );
mbedtls_sha1_finish( &mbedtls_sha1, hash + 16 );
mbedtls_md5_free( &mbedtls_md5 );
mbedtls_sha1_free( &mbedtls_sha1 );
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \
MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( md_alg != MBEDTLS_MD_NONE )
{
mbedtls_md_context_t ctx;
mbedtls_md_init( &ctx );
/* Info from md_alg will be used instead */
hashlen = 0;
/*
* digitally-signed struct {
* opaque client_random[32];
* opaque server_random[32];
* ServerDHParams params;
* };
*/
if( ( ret = mbedtls_md_setup( &ctx,
mbedtls_md_info_from_type( md_alg ), 0 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_md_setup", ret );
return( ret );
}
mbedtls_md_starts( &ctx );
mbedtls_md_update( &ctx, ssl->handshake->randbytes, 64 );
mbedtls_md_update( &ctx, params, params_len );
mbedtls_md_finish( &ctx, hash );
mbedtls_md_free( &ctx );
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_SSL_DEBUG_BUF( 3, "parameters hash", hash, hashlen != 0 ? hashlen :
(unsigned int) ( mbedtls_md_get_size( mbedtls_md_info_from_type( md_alg ) ) ) );
if( ssl->session_negotiate->peer_cert == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "certificate required" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/*
* Verify signature
*/
if( ! mbedtls_pk_can_do( &ssl->session_negotiate->peer_cert->pk, pk_alg ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH );
}
if( ( ret = mbedtls_pk_verify( &ssl->session_negotiate->peer_cert->pk,
md_alg, hash, hashlen, p, sig_len ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_verify", ret );
return( ret );
}
}
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
exit:
ssl->state++;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server key exchange" ) );
return( 0 );
}
#if !defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
static int ssl_parse_certificate_request( mbedtls_ssl_context *ssl )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate request" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate request" ) );
ssl->state++;
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#else
static int ssl_parse_certificate_request( mbedtls_ssl_context *ssl )
{
int ret;
unsigned char *buf, *p;
size_t n = 0, m = 0;
size_t cert_type_len = 0, dn_len = 0;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate request" ) );
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate request" ) );
ssl->state++;
return( 0 );
}
if( ssl->record_read == 0 )
{
if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
ssl->record_read = 1;
}
ssl->client_auth = 0;
ssl->state++;
if( ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE_REQUEST )
ssl->client_auth++;
MBEDTLS_SSL_DEBUG_MSG( 3, ( "got %s certificate request",
ssl->client_auth ? "a" : "no" ) );
if( ssl->client_auth == 0 )
goto exit;
ssl->record_read = 0;
// TODO: handshake_failure alert for an anonymous server to request
// client authentication
/*
* struct {
* ClientCertificateType certificate_types<1..2^8-1>;
* SignatureAndHashAlgorithm
* supported_signature_algorithms<2^16-1>; -- TLS 1.2 only
* DistinguishedName certificate_authorities<0..2^16-1>;
* } CertificateRequest;
*/
buf = ssl->in_msg;
// Retrieve cert types
//
cert_type_len = buf[mbedtls_ssl_hs_hdr_len( ssl )];
n = cert_type_len;
if( ssl->in_hslen < mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST );
}
p = buf + mbedtls_ssl_hs_hdr_len( ssl ) + 1;
while( cert_type_len > 0 )
{
#if defined(MBEDTLS_RSA_C)
if( *p == MBEDTLS_SSL_CERT_TYPE_RSA_SIGN &&
mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_RSA ) )
{
ssl->handshake->cert_type = MBEDTLS_SSL_CERT_TYPE_RSA_SIGN;
break;
}
else
#endif
#if defined(MBEDTLS_ECDSA_C)
if( *p == MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN &&
mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_ECDSA ) )
{
ssl->handshake->cert_type = MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN;
break;
}
else
#endif
{
; /* Unsupported cert type, ignore */
}
cert_type_len--;
p++;
}
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
/* Ignored, see comments about hash in write_certificate_verify */
// TODO: should check the signature part against our pk_key though
size_t sig_alg_len = ( ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 1 + n] << 8 )
| ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n] ) );
m += 2;
n += sig_alg_len;
if( ssl->in_hslen < mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST );
}
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
/* Ignore certificate_authorities, we only have one cert anyway */
// TODO: should not send cert if no CA matches
dn_len = ( ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 1 + m + n] << 8 )
| ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 2 + m + n] ) );
n += dn_len;
if( ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) + 3 + m + n )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST );
}
exit:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate request" ) );
return( 0 );
}
#endif /* !MBEDTLS_KEY_EXCHANGE_RSA_ENABLED &&
!MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED &&
!MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED &&
!MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
static int ssl_parse_server_hello_done( mbedtls_ssl_context *ssl )
{
int ret;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server hello done" ) );
if( ssl->record_read == 0 )
{
if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
}
ssl->record_read = 0;
if( ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) ||
ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_HELLO_DONE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE );
}
ssl->state++;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
mbedtls_ssl_recv_flight_completed( ssl );
#endif
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello done" ) );
return( 0 );
}
static int ssl_write_client_key_exchange( mbedtls_ssl_context *ssl )
{
int ret;
size_t i, n;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write client key exchange" ) );
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA )
{
/*
* DHM key exchange -- send G^X mod P
*/
n = ssl->handshake->dhm_ctx.len;
ssl->out_msg[4] = (unsigned char)( n >> 8 );
ssl->out_msg[5] = (unsigned char)( n );
i = 6;
ret = mbedtls_dhm_make_public( &ssl->handshake->dhm_ctx,
(int) mbedtls_mpi_size( &ssl->handshake->dhm_ctx.P ),
&ssl->out_msg[i], n,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_make_public", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: X ", &ssl->handshake->dhm_ctx.X );
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: GX", &ssl->handshake->dhm_ctx.GX );
if( ( ret = mbedtls_dhm_calc_secret( &ssl->handshake->dhm_ctx,
ssl->handshake->premaster,
MBEDTLS_PREMASTER_SIZE,
&ssl->handshake->pmslen,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_calc_secret", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA )
{
/*
* ECDH key exchange -- send client public value
*/
i = 4;
ret = mbedtls_ecdh_make_public( &ssl->handshake->ecdh_ctx,
&n,
&ssl->out_msg[i], 1000,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_make_public", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_ECP( 3, "ECDH: Q", &ssl->handshake->ecdh_ctx.Q );
if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx,
&ssl->handshake->pmslen,
ssl->handshake->premaster,
MBEDTLS_MPI_MAX_SIZE,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_calc_secret", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MPI( 3, "ECDH: z", &ssl->handshake->ecdh_ctx.z );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
/*
* opaque psk_identity<0..2^16-1>;
*/
if( ssl->conf->psk == NULL || ssl->conf->psk_identity == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no private key for PSK" ) );
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED );
}
i = 4;
n = ssl->conf->psk_identity_len;
if( i + 2 + n > MBEDTLS_SSL_MAX_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "psk identity too long or "
"SSL buffer too short" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
ssl->out_msg[i++] = (unsigned char)( n >> 8 );
ssl->out_msg[i++] = (unsigned char)( n );
memcpy( ssl->out_msg + i, ssl->conf->psk_identity, ssl->conf->psk_identity_len );
i += ssl->conf->psk_identity_len;
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK )
{
n = 0;
}
else
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
{
if( ( ret = ssl_write_encrypted_pms( ssl, i, &n, 2 ) ) != 0 )
return( ret );
}
else
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK )
{
/*
* ClientDiffieHellmanPublic public (DHM send G^X mod P)
*/
n = ssl->handshake->dhm_ctx.len;
if( i + 2 + n > MBEDTLS_SSL_MAX_CONTENT_LEN )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "psk identity or DHM size too long"
" or SSL buffer too short" ) );
return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
}
ssl->out_msg[i++] = (unsigned char)( n >> 8 );
ssl->out_msg[i++] = (unsigned char)( n );
ret = mbedtls_dhm_make_public( &ssl->handshake->dhm_ctx,
(int) mbedtls_mpi_size( &ssl->handshake->dhm_ctx.P ),
&ssl->out_msg[i], n,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_make_public", ret );
return( ret );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
/*
* ClientECDiffieHellmanPublic public;
*/
ret = mbedtls_ecdh_make_public( &ssl->handshake->ecdh_ctx, &n,
&ssl->out_msg[i], MBEDTLS_SSL_MAX_CONTENT_LEN - i,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_make_public", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_ECP( 3, "ECDH: Q", &ssl->handshake->ecdh_ctx.Q );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
if( ( ret = mbedtls_ssl_psk_derive_premaster( ssl,
ciphersuite_info->key_exchange ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_psk_derive_premaster", ret );
return( ret );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA )
{
i = 4;
if( ( ret = ssl_write_encrypted_pms( ssl, i, &n, 0 ) ) != 0 )
return( ret );
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
i = 4;
ret = mbedtls_ecjpake_write_round_two( &ssl->handshake->ecjpake_ctx,
ssl->out_msg + i, MBEDTLS_SSL_MAX_CONTENT_LEN - i, &n,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_write_round_two", ret );
return( ret );
}
ret = mbedtls_ecjpake_derive_secret( &ssl->handshake->ecjpake_ctx,
ssl->handshake->premaster, 32, &ssl->handshake->pmslen,
ssl->conf->f_rng, ssl->conf->p_rng );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_derive_secret", ret );
return( ret );
}
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */
{
((void) ciphersuite_info);
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
ssl->out_msglen = i + n;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE;
ssl->state++;
if( ( ret = mbedtls_ssl_write_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write client key exchange" ) );
return( 0 );
}
#if !defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) && \
!defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
static int ssl_write_certificate_verify( mbedtls_ssl_context *ssl )
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
int ret;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) );
if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret );
return( ret );
}
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) );
ssl->state++;
return( 0 );
}
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
#else
static int ssl_write_certificate_verify( mbedtls_ssl_context *ssl )
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
size_t n = 0, offset = 0;
unsigned char hash[48];
unsigned char *hash_start = hash;
mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE;
unsigned int hashlen;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) );
if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret );
return( ret );
}
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) );
ssl->state++;
return( 0 );
}
if( ssl->client_auth == 0 || mbedtls_ssl_own_cert( ssl ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) );
ssl->state++;
return( 0 );
}
if( mbedtls_ssl_own_key( ssl ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no private key for certificate" ) );
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED );
}
/*
* Make an RSA signature of the handshake digests
*/
ssl->handshake->calc_verify( ssl, hash );
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 )
{
/*
* digitally-signed struct {
* opaque md5_hash[16];
* opaque sha_hash[20];
* };
*
* md5_hash
* MD5(handshake_messages);
*
* sha_hash
* SHA(handshake_messages);
*/
hashlen = 36;
md_alg = MBEDTLS_MD_NONE;
/*
* For ECDSA, default hash is SHA-1 only
*/
if( mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_ECDSA ) )
{
hash_start += 16;
hashlen -= 16;
md_alg = MBEDTLS_MD_SHA1;
}
}
else
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \
MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
/*
* digitally-signed struct {
* opaque handshake_messages[handshake_messages_length];
* };
*
* Taking shortcut here. We assume that the server always allows the
* PRF Hash function and has sent it in the allowed signature
* algorithms list received in the Certificate Request message.
*
* Until we encounter a server that does not, we will take this
* shortcut.
*
* Reason: Otherwise we should have running hashes for SHA512 and SHA224
* in order to satisfy 'weird' needs from the server side.
*/
if( ssl->transform_negotiate->ciphersuite_info->mac ==
MBEDTLS_MD_SHA384 )
{
md_alg = MBEDTLS_MD_SHA384;
ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA384;
}
else
{
md_alg = MBEDTLS_MD_SHA256;
ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA256;
}
ssl->out_msg[5] = mbedtls_ssl_sig_from_pk( mbedtls_ssl_own_key( ssl ) );
/* Info from md_alg will be used instead */
hashlen = 0;
offset = 2;
}
else
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
if( ( ret = mbedtls_pk_sign( mbedtls_ssl_own_key( ssl ), md_alg, hash_start, hashlen,
ssl->out_msg + 6 + offset, &n,
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_sign", ret );
return( ret );
}
ssl->out_msg[4 + offset] = (unsigned char)( n >> 8 );
ssl->out_msg[5 + offset] = (unsigned char)( n );
ssl->out_msglen = 6 + n + offset;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CERTIFICATE_VERIFY;
ssl->state++;
if( ( ret = mbedtls_ssl_write_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_record", ret );
return( ret );
}
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write certificate verify" ) );
return( ret );
}
#endif /* !MBEDTLS_KEY_EXCHANGE_RSA_ENABLED &&
!MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED &&
!MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
static int ssl_parse_new_session_ticket( mbedtls_ssl_context *ssl )
{
int ret;
uint32_t lifetime;
size_t ticket_len;
unsigned char *ticket;
const unsigned char *msg;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse new session ticket" ) );
if( ( ret = mbedtls_ssl_read_record( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret );
return( ret );
}
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) );
return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE );
}
/*
* struct {
* uint32 ticket_lifetime_hint;
* opaque ticket<0..2^16-1>;
* } NewSessionTicket;
*
* 0 . 3 ticket_lifetime_hint
* 4 . 5 ticket_len (n)
* 6 . 5+n ticket content
*/
if( ssl->in_msg[0] != MBEDTLS_SSL_HS_NEW_SESSION_TICKET ||
ssl->in_hslen < 6 + mbedtls_ssl_hs_hdr_len( ssl ) )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET );
}
msg = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
lifetime = ( msg[0] << 24 ) | ( msg[1] << 16 ) |
( msg[2] << 8 ) | ( msg[3] );
ticket_len = ( msg[4] << 8 ) | ( msg[5] );
if( ticket_len + 6 + mbedtls_ssl_hs_hdr_len( ssl ) != ssl->in_hslen )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) );
return( MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET );
}
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket length: %d", ticket_len ) );
/* We're not waiting for a NewSessionTicket message any more */
ssl->handshake->new_session_ticket = 0;
ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC;
/*
* Zero-length ticket means the server changed his mind and doesn't want
* to send a ticket after all, so just forget it
*/
if( ticket_len == 0 )
return( 0 );
mbedtls_zeroize( ssl->session_negotiate->ticket,
ssl->session_negotiate->ticket_len );
mbedtls_free( ssl->session_negotiate->ticket );
ssl->session_negotiate->ticket = NULL;
ssl->session_negotiate->ticket_len = 0;
if( ( ticket = mbedtls_calloc( 1, ticket_len ) ) == NULL )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "ticket alloc failed" ) );
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
}
memcpy( ticket, msg + 6, ticket_len );
ssl->session_negotiate->ticket = ticket;
ssl->session_negotiate->ticket_len = ticket_len;
ssl->session_negotiate->ticket_lifetime = lifetime;
/*
* RFC 5077 section 3.4:
* "If the client receives a session ticket from the server, then it
* discards any Session ID that was sent in the ServerHello."
*/
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket in use, discarding session id" ) );
ssl->session_negotiate->id_len = 0;
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse new session ticket" ) );
return( 0 );
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
/*
* SSL handshake -- client side -- single step
*/
int mbedtls_ssl_handshake_client_step( mbedtls_ssl_context *ssl )
{
int ret = 0;
if( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER || ssl->handshake == NULL )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
MBEDTLS_SSL_DEBUG_MSG( 2, ( "client state: %d", ssl->state ) );
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
return( ret );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->retransmit_state == MBEDTLS_SSL_RETRANS_SENDING )
{
if( ( ret = mbedtls_ssl_resend( ssl ) ) != 0 )
return( ret );
}
#endif
/* Change state now, so that it is right in mbedtls_ssl_read_record(), used
* by DTLS for dropping out-of-sequence ChangeCipherSpec records */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
if( ssl->state == MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC &&
ssl->handshake->new_session_ticket != 0 )
{
ssl->state = MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET;
}
#endif
switch( ssl->state )
{
case MBEDTLS_SSL_HELLO_REQUEST:
ssl->state = MBEDTLS_SSL_CLIENT_HELLO;
break;
/*
* ==> ClientHello
*/
case MBEDTLS_SSL_CLIENT_HELLO:
ret = ssl_write_client_hello( ssl );
break;
/*
* <== ServerHello
* Certificate
* ( ServerKeyExchange )
* ( CertificateRequest )
* ServerHelloDone
*/
case MBEDTLS_SSL_SERVER_HELLO:
ret = ssl_parse_server_hello( ssl );
break;
case MBEDTLS_SSL_SERVER_CERTIFICATE:
ret = mbedtls_ssl_parse_certificate( ssl );
break;
case MBEDTLS_SSL_SERVER_KEY_EXCHANGE:
ret = ssl_parse_server_key_exchange( ssl );
break;
case MBEDTLS_SSL_CERTIFICATE_REQUEST:
ret = ssl_parse_certificate_request( ssl );
break;
case MBEDTLS_SSL_SERVER_HELLO_DONE:
ret = ssl_parse_server_hello_done( ssl );
break;
/*
* ==> ( Certificate/Alert )
* ClientKeyExchange
* ( CertificateVerify )
* ChangeCipherSpec
* Finished
*/
case MBEDTLS_SSL_CLIENT_CERTIFICATE:
ret = mbedtls_ssl_write_certificate( ssl );
break;
case MBEDTLS_SSL_CLIENT_KEY_EXCHANGE:
ret = ssl_write_client_key_exchange( ssl );
break;
case MBEDTLS_SSL_CERTIFICATE_VERIFY:
ret = ssl_write_certificate_verify( ssl );
break;
case MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC:
ret = mbedtls_ssl_write_change_cipher_spec( ssl );
break;
case MBEDTLS_SSL_CLIENT_FINISHED:
ret = mbedtls_ssl_write_finished( ssl );
break;
/*
* <== ( NewSessionTicket )
* ChangeCipherSpec
* Finished
*/
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
case MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET:
ret = ssl_parse_new_session_ticket( ssl );
break;
#endif
case MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC:
ret = mbedtls_ssl_parse_change_cipher_spec( ssl );
break;
case MBEDTLS_SSL_SERVER_FINISHED:
ret = mbedtls_ssl_parse_finished( ssl );
break;
case MBEDTLS_SSL_FLUSH_BUFFERS:
MBEDTLS_SSL_DEBUG_MSG( 2, ( "handshake: done" ) );
ssl->state = MBEDTLS_SSL_HANDSHAKE_WRAPUP;
break;
case MBEDTLS_SSL_HANDSHAKE_WRAPUP:
mbedtls_ssl_handshake_wrapup( ssl );
break;
default:
MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid state %d", ssl->state ) );
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
}
return( ret );
}
#endif /* MBEDTLS_SSL_CLI_C */
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