/* | |
* SSLv3/TLSv1 server-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_SRV_C) | |
#if defined(MBEDTLS_PLATFORM_C) | |
#include "mbedtls/platform.h" | |
#else | |
#include <stdlib.h> | |
#define mbedtls_calloc calloc | |
#define mbedtls_free free | |
#endif | |
#include "mbedtls/debug.h" | |
#include "mbedtls/ssl.h" | |
#include "mbedtls/ssl_internal.h" | |
#include "mbedtls/platform_util.h" | |
#include <string.h> | |
#if defined(MBEDTLS_ECP_C) | |
#include "mbedtls/ecp.h" | |
#endif | |
#if defined(MBEDTLS_HAVE_TIME) | |
#include "mbedtls/platform_time.h" | |
#endif | |
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) | |
int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl, | |
const unsigned char *info, | |
size_t ilen ) | |
{ | |
if( ssl->conf->endpoint != MBEDTLS_SSL_IS_SERVER ) | |
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); | |
mbedtls_free( ssl->cli_id ); | |
if( ( ssl->cli_id = mbedtls_calloc( 1, ilen ) ) == NULL ) | |
return( MBEDTLS_ERR_SSL_ALLOC_FAILED ); | |
memcpy( ssl->cli_id, info, ilen ); | |
ssl->cli_id_len = ilen; | |
return( 0 ); | |
} | |
void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf, | |
mbedtls_ssl_cookie_write_t *f_cookie_write, | |
mbedtls_ssl_cookie_check_t *f_cookie_check, | |
void *p_cookie ) | |
{ | |
conf->f_cookie_write = f_cookie_write; | |
conf->f_cookie_check = f_cookie_check; | |
conf->p_cookie = p_cookie; | |
} | |
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */ | |
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | |
static int ssl_parse_servername_ext( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
int ret; | |
size_t servername_list_size, hostname_len; | |
const unsigned char *p; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "parse ServerName extension" ) ); | |
if( len < 2 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
servername_list_size = ( ( buf[0] << 8 ) | ( buf[1] ) ); | |
if( servername_list_size + 2 != len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
p = buf + 2; | |
while( servername_list_size > 2 ) | |
{ | |
hostname_len = ( ( p[1] << 8 ) | p[2] ); | |
if( hostname_len + 3 > servername_list_size ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
if( p[0] == MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME ) | |
{ | |
ret = ssl->conf->f_sni( ssl->conf->p_sni, | |
ssl, p + 3, hostname_len ); | |
if( ret != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_sni_wrapper", ret ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
return( 0 ); | |
} | |
servername_list_size -= hostname_len + 3; | |
p += hostname_len + 3; | |
} | |
if( servername_list_size != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) | |
static int ssl_conf_has_psk_or_cb( mbedtls_ssl_config const *conf ) | |
{ | |
if( conf->f_psk != NULL ) | |
return( 1 ); | |
if( conf->psk_identity_len == 0 || conf->psk_identity == NULL ) | |
return( 0 ); | |
if( conf->psk != NULL && conf->psk_len != 0 ) | |
return( 1 ); | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
if( conf->psk_opaque != 0 ) | |
return( 1 ); | |
#endif /* MBEDTLS_USE_PSA_CRYPTO */ | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
static int ssl_use_opaque_psk( mbedtls_ssl_context const *ssl ) | |
{ | |
if( ssl->conf->f_psk != NULL ) | |
{ | |
/* If we've used a callback to select the PSK, | |
* the static configuration is irrelevant. */ | |
if( ssl->handshake->psk_opaque != 0 ) | |
return( 1 ); | |
return( 0 ); | |
} | |
if( ssl->conf->psk_opaque != 0 ) | |
return( 1 ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_USE_PSA_CRYPTO */ | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */ | |
static int ssl_parse_renegotiation_info( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
#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 || | |
buf[0] != ssl->verify_data_len || | |
mbedtls_ssl_safer_memcmp( buf + 1, ssl->peer_verify_data, | |
ssl->verify_data_len ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-matching renegotiation info" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
} | |
else | |
#endif /* MBEDTLS_SSL_RENEGOTIATION */ | |
{ | |
if( len != 1 || buf[0] != 0x0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-zero length renegotiation info" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION; | |
} | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
/* | |
* Status of the implementation of signature-algorithms extension: | |
* | |
* Currently, we are only considering the signature-algorithm extension | |
* to pick a ciphersuite which allows us to send the ServerKeyExchange | |
* message with a signature-hash combination that the user allows. | |
* | |
* We do *not* check whether all certificates in our certificate | |
* chain are signed with an allowed signature-hash pair. | |
* This needs to be done at a later stage. | |
* | |
*/ | |
static int ssl_parse_signature_algorithms_ext( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
size_t sig_alg_list_size; | |
const unsigned char *p; | |
const unsigned char *end = buf + len; | |
mbedtls_md_type_t md_cur; | |
mbedtls_pk_type_t sig_cur; | |
if ( len < 2 ) { | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
sig_alg_list_size = ( ( buf[0] << 8 ) | ( buf[1] ) ); | |
if( sig_alg_list_size + 2 != len || | |
sig_alg_list_size % 2 != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* Currently we only guarantee signing the ServerKeyExchange message according | |
* to the constraints specified in this extension (see above), so it suffices | |
* to remember only one suitable hash for each possible signature algorithm. | |
* | |
* This will change when we also consider certificate signatures, | |
* in which case we will need to remember the whole signature-hash | |
* pair list from the extension. | |
*/ | |
for( p = buf + 2; p < end; p += 2 ) | |
{ | |
/* Silently ignore unknown signature or hash algorithms. */ | |
if( ( sig_cur = mbedtls_ssl_pk_alg_from_sig( p[1] ) ) == MBEDTLS_PK_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, signature_algorithm ext" | |
" unknown sig alg encoding %d", p[1] ) ); | |
continue; | |
} | |
/* Check if we support the hash the user proposes */ | |
md_cur = mbedtls_ssl_md_alg_from_hash( p[0] ); | |
if( md_cur == MBEDTLS_MD_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, signature_algorithm ext:" | |
" unknown hash alg encoding %d", p[0] ) ); | |
continue; | |
} | |
if( mbedtls_ssl_check_sig_hash( ssl, md_cur ) == 0 ) | |
{ | |
mbedtls_ssl_sig_hash_set_add( &ssl->handshake->hash_algs, sig_cur, md_cur ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, signature_algorithm ext:" | |
" match sig %d and hash %d", | |
sig_cur, md_cur ) ); | |
} | |
else | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, signature_algorithm ext: " | |
"hash alg %d not supported", md_cur ) ); | |
} | |
} | |
return( 0 ); | |
} | |
#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 int ssl_parse_supported_elliptic_curves( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
size_t list_size, our_size; | |
const unsigned char *p; | |
const mbedtls_ecp_curve_info *curve_info, **curves; | |
if ( len < 2 ) { | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
list_size = ( ( buf[0] << 8 ) | ( buf[1] ) ); | |
if( list_size + 2 != len || | |
list_size % 2 != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* Should never happen unless client duplicates the extension */ | |
if( ssl->handshake->curves != NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* Don't allow our peer to make us allocate too much memory, | |
* and leave room for a final 0 */ | |
our_size = list_size / 2 + 1; | |
if( our_size > MBEDTLS_ECP_DP_MAX ) | |
our_size = MBEDTLS_ECP_DP_MAX; | |
if( ( curves = mbedtls_calloc( our_size, sizeof( *curves ) ) ) == NULL ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR ); | |
return( MBEDTLS_ERR_SSL_ALLOC_FAILED ); | |
} | |
ssl->handshake->curves = curves; | |
p = buf + 2; | |
while( list_size > 0 && our_size > 1 ) | |
{ | |
curve_info = mbedtls_ecp_curve_info_from_tls_id( ( p[0] << 8 ) | p[1] ); | |
if( curve_info != NULL ) | |
{ | |
*curves++ = curve_info; | |
our_size--; | |
} | |
list_size -= 2; | |
p += 2; | |
} | |
return( 0 ); | |
} | |
static int ssl_parse_supported_point_formats( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
size_t list_size; | |
const unsigned char *p; | |
if( len == 0 || (size_t)( buf[0] + 1 ) != len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
list_size = buf[0]; | |
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++; | |
} | |
return( 0 ); | |
} | |
#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( mbedtls_ecjpake_check( &ssl->handshake->ecjpake_ctx ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip ecjpake kkpp extension" ) ); | |
return( 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 ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( ret ); | |
} | |
/* Only mark the extension as OK when we're sure it is */ | |
ssl->handshake->cli_exts |= MBEDTLS_TLS_EXT_ECJPAKE_KKPP_OK; | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ | |
#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 ) | |
{ | |
if( len != 1 || buf[0] >= MBEDTLS_SSL_MAX_FRAG_LEN_INVALID ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->session_negotiate->mfl_code = buf[0]; | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ | |
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | |
static int ssl_parse_cid_ext( mbedtls_ssl_context *ssl, | |
const unsigned char *buf, | |
size_t len ) | |
{ | |
size_t peer_cid_len; | |
/* CID extension only makes sense in DTLS */ | |
if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* | |
* Quoting draft-ietf-tls-dtls-connection-id-05 | |
* https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05 | |
* | |
* struct { | |
* opaque cid<0..2^8-1>; | |
* } ConnectionId; | |
*/ | |
if( len < 1 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
peer_cid_len = *buf++; | |
len--; | |
if( len != peer_cid_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* Ignore CID if the user has disabled its use. */ | |
if( ssl->negotiate_cid == MBEDTLS_SSL_CID_DISABLED ) | |
{ | |
/* Leave ssl->handshake->cid_in_use in its default | |
* value of MBEDTLS_SSL_CID_DISABLED. */ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Client sent CID extension, but CID disabled" ) ); | |
return( 0 ); | |
} | |
if( peer_cid_len > MBEDTLS_SSL_CID_OUT_LEN_MAX ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->handshake->cid_in_use = MBEDTLS_SSL_CID_ENABLED; | |
ssl->handshake->peer_cid_len = (uint8_t) peer_cid_len; | |
memcpy( ssl->handshake->peer_cid, buf, peer_cid_len ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "Use of CID extension negotiated" ) ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "Client CID", buf, peer_cid_len ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | |
#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( len != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
((void) buf); | |
if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_ENABLED ) | |
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( len != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
((void) buf); | |
if( ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_ENABLED && | |
ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_0 ) | |
{ | |
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( len != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
((void) buf); | |
if( ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_ENABLED && | |
ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_0 ) | |
{ | |
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, | |
unsigned char *buf, | |
size_t len ) | |
{ | |
int ret; | |
mbedtls_ssl_session session; | |
mbedtls_ssl_session_init( &session ); | |
if( ssl->conf->f_ticket_parse == NULL || | |
ssl->conf->f_ticket_write == NULL ) | |
{ | |
return( 0 ); | |
} | |
/* Remember the client asked us to send a new ticket */ | |
ssl->handshake->new_session_ticket = 1; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket length: %d", len ) ); | |
if( len == 0 ) | |
return( 0 ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket rejected: renegotiating" ) ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_RENEGOTIATION */ | |
/* | |
* Failures are ok: just ignore the ticket and proceed. | |
*/ | |
if( ( ret = ssl->conf->f_ticket_parse( ssl->conf->p_ticket, &session, | |
buf, len ) ) != 0 ) | |
{ | |
mbedtls_ssl_session_free( &session ); | |
if( ret == MBEDTLS_ERR_SSL_INVALID_MAC ) | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket is not authentic" ) ); | |
else if( ret == MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED ) | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket is expired" ) ); | |
else | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_ticket_parse", ret ); | |
return( 0 ); | |
} | |
/* | |
* Keep the session ID sent by the client, since we MUST send it back to | |
* inform them we're accepting the ticket (RFC 5077 section 3.4) | |
*/ | |
session.id_len = ssl->session_negotiate->id_len; | |
memcpy( &session.id, ssl->session_negotiate->id, session.id_len ); | |
mbedtls_ssl_session_free( ssl->session_negotiate ); | |
memcpy( ssl->session_negotiate, &session, sizeof( mbedtls_ssl_session ) ); | |
/* Zeroize instead of free as we copied the content */ | |
mbedtls_platform_zeroize( &session, sizeof( mbedtls_ssl_session ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "session successfully restored from ticket" ) ); | |
ssl->handshake->resume = 1; | |
/* Don't send a new ticket after all, this one is OK */ | |
ssl->handshake->new_session_ticket = 0; | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
#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, cur_len, ours_len; | |
const unsigned char *theirs, *start, *end; | |
const char **ours; | |
/* If ALPN not configured, just ignore the extension */ | |
if( ssl->conf->alpn_list == NULL ) | |
return( 0 ); | |
/* | |
* opaque ProtocolName<1..2^8-1>; | |
* | |
* struct { | |
* ProtocolName protocol_name_list<2..2^16-1> | |
* } ProtocolNameList; | |
*/ | |
/* Min length is 2 (list_len) + 1 (name_len) + 1 (name) */ | |
if( len < 4 ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
list_len = ( buf[0] << 8 ) | buf[1]; | |
if( list_len != len - 2 ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* | |
* Validate peer's list (lengths) | |
*/ | |
start = buf + 2; | |
end = buf + len; | |
for( theirs = start; theirs != end; theirs += cur_len ) | |
{ | |
cur_len = *theirs++; | |
/* Current identifier must fit in list */ | |
if( cur_len > (size_t)( end - theirs ) ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* Empty strings MUST NOT be included */ | |
if( cur_len == 0 ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
} | |
/* | |
* Use our order of preference | |
*/ | |
for( ours = ssl->conf->alpn_list; *ours != NULL; ours++ ) | |
{ | |
ours_len = strlen( *ours ); | |
for( theirs = start; theirs != end; theirs += cur_len ) | |
{ | |
cur_len = *theirs++; | |
if( cur_len == ours_len && | |
memcmp( theirs, *ours, cur_len ) == 0 ) | |
{ | |
ssl->alpn_chosen = *ours; | |
return( 0 ); | |
} | |
} | |
} | |
/* If we get there, no match was found */ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
#endif /* MBEDTLS_SSL_ALPN */ | |
/* | |
* Auxiliary functions for ServerHello parsing and related actions | |
*/ | |
#if defined(MBEDTLS_X509_CRT_PARSE_C) | |
/* | |
* Return 0 if the given key uses one of the acceptable curves, -1 otherwise | |
*/ | |
#if defined(MBEDTLS_ECDSA_C) | |
static int ssl_check_key_curve( mbedtls_pk_context *pk, | |
const mbedtls_ecp_curve_info **curves ) | |
{ | |
const mbedtls_ecp_curve_info **crv = curves; | |
mbedtls_ecp_group_id grp_id = mbedtls_pk_ec( *pk )->grp.id; | |
while( *crv != NULL ) | |
{ | |
if( (*crv)->grp_id == grp_id ) | |
return( 0 ); | |
crv++; | |
} | |
return( -1 ); | |
} | |
#endif /* MBEDTLS_ECDSA_C */ | |
/* | |
* Try picking a certificate for this ciphersuite, | |
* return 0 on success and -1 on failure. | |
*/ | |
static int ssl_pick_cert( mbedtls_ssl_context *ssl, | |
const mbedtls_ssl_ciphersuite_t * ciphersuite_info ) | |
{ | |
mbedtls_ssl_key_cert *cur, *list, *fallback = NULL; | |
mbedtls_pk_type_t pk_alg = | |
mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info ); | |
uint32_t flags; | |
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | |
if( ssl->handshake->sni_key_cert != NULL ) | |
list = ssl->handshake->sni_key_cert; | |
else | |
#endif | |
list = ssl->conf->key_cert; | |
if( pk_alg == MBEDTLS_PK_NONE ) | |
return( 0 ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite requires certificate" ) ); | |
if( list == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server has no certificate" ) ); | |
return( -1 ); | |
} | |
for( cur = list; cur != NULL; cur = cur->next ) | |
{ | |
MBEDTLS_SSL_DEBUG_CRT( 3, "candidate certificate chain, certificate", | |
cur->cert ); | |
if( ! mbedtls_pk_can_do( &cur->cert->pk, pk_alg ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "certificate mismatch: key type" ) ); | |
continue; | |
} | |
/* | |
* This avoids sending the client a cert it'll reject based on | |
* keyUsage or other extensions. | |
* | |
* It also allows the user to provision different certificates for | |
* different uses based on keyUsage, eg if they want to avoid signing | |
* and decrypting with the same RSA key. | |
*/ | |
if( mbedtls_ssl_check_cert_usage( cur->cert, ciphersuite_info, | |
MBEDTLS_SSL_IS_SERVER, &flags ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "certificate mismatch: " | |
"(extended) key usage extension" ) ); | |
continue; | |
} | |
#if defined(MBEDTLS_ECDSA_C) | |
if( pk_alg == MBEDTLS_PK_ECDSA && | |
ssl_check_key_curve( &cur->cert->pk, ssl->handshake->curves ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "certificate mismatch: elliptic curve" ) ); | |
continue; | |
} | |
#endif | |
/* | |
* Try to select a SHA-1 certificate for pre-1.2 clients, but still | |
* present them a SHA-higher cert rather than failing if it's the only | |
* one we got that satisfies the other conditions. | |
*/ | |
if( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 && | |
cur->cert->sig_md != MBEDTLS_MD_SHA1 ) | |
{ | |
if( fallback == NULL ) | |
fallback = cur; | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "certificate not preferred: " | |
"sha-2 with pre-TLS 1.2 client" ) ); | |
continue; | |
} | |
} | |
/* If we get there, we got a winner */ | |
break; | |
} | |
if( cur == NULL ) | |
cur = fallback; | |
/* Do not update ssl->handshake->key_cert unless there is a match */ | |
if( cur != NULL ) | |
{ | |
ssl->handshake->key_cert = cur; | |
MBEDTLS_SSL_DEBUG_CRT( 3, "selected certificate chain, certificate", | |
ssl->handshake->key_cert->cert ); | |
return( 0 ); | |
} | |
return( -1 ); | |
} | |
#endif /* MBEDTLS_X509_CRT_PARSE_C */ | |
/* | |
* Check if a given ciphersuite is suitable for use with our config/keys/etc | |
* Sets ciphersuite_info only if the suite matches. | |
*/ | |
static int ssl_ciphersuite_match( mbedtls_ssl_context *ssl, int suite_id, | |
const mbedtls_ssl_ciphersuite_t **ciphersuite_info ) | |
{ | |
const mbedtls_ssl_ciphersuite_t *suite_info; | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
mbedtls_pk_type_t sig_type; | |
#endif | |
suite_info = mbedtls_ssl_ciphersuite_from_id( suite_id ); | |
if( suite_info == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "trying ciphersuite: %s", suite_info->name ) ); | |
if( suite_info->min_minor_ver > ssl->minor_ver || | |
suite_info->max_minor_ver < ssl->minor_ver ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: version" ) ); | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && | |
( suite_info->flags & MBEDTLS_CIPHERSUITE_NODTLS ) ) | |
return( 0 ); | |
#endif | |
#if defined(MBEDTLS_ARC4_C) | |
if( ssl->conf->arc4_disabled == MBEDTLS_SSL_ARC4_DISABLED && | |
suite_info->cipher == MBEDTLS_CIPHER_ARC4_128 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: rc4" ) ); | |
return( 0 ); | |
} | |
#endif | |
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) | |
if( suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE && | |
( ssl->handshake->cli_exts & MBEDTLS_TLS_EXT_ECJPAKE_KKPP_OK ) == 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: ecjpake " | |
"not configured or ext missing" ) ); | |
return( 0 ); | |
} | |
#endif | |
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) | |
if( mbedtls_ssl_ciphersuite_uses_ec( suite_info ) && | |
( ssl->handshake->curves == NULL || | |
ssl->handshake->curves[0] == NULL ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: " | |
"no common elliptic curve" ) ); | |
return( 0 ); | |
} | |
#endif | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) | |
/* If the ciphersuite requires a pre-shared key and we don't | |
* have one, skip it now rather than failing later */ | |
if( mbedtls_ssl_ciphersuite_uses_psk( suite_info ) && | |
ssl_conf_has_psk_or_cb( ssl->conf ) == 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: no pre-shared key" ) ); | |
return( 0 ); | |
} | |
#endif | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
/* If the ciphersuite requires signing, check whether | |
* a suitable hash algorithm is present. */ | |
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) | |
{ | |
sig_type = mbedtls_ssl_get_ciphersuite_sig_alg( suite_info ); | |
if( sig_type != MBEDTLS_PK_NONE && | |
mbedtls_ssl_sig_hash_set_find( &ssl->handshake->hash_algs, sig_type ) == MBEDTLS_MD_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: no suitable hash algorithm " | |
"for signature algorithm %d", sig_type ) ); | |
return( 0 ); | |
} | |
} | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && | |
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ | |
#if defined(MBEDTLS_X509_CRT_PARSE_C) | |
/* | |
* Final check: if ciphersuite requires us to have a | |
* certificate/key of a particular type: | |
* - select the appropriate certificate if we have one, or | |
* - try the next ciphersuite if we don't | |
* This must be done last since we modify the key_cert list. | |
*/ | |
if( ssl_pick_cert( ssl, suite_info ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: " | |
"no suitable certificate" ) ); | |
return( 0 ); | |
} | |
#endif | |
*ciphersuite_info = suite_info; | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO) | |
static int ssl_parse_client_hello_v2( mbedtls_ssl_context *ssl ) | |
{ | |
int ret, got_common_suite; | |
unsigned int i, j; | |
size_t n; | |
unsigned int ciph_len, sess_len, chal_len; | |
unsigned char *buf, *p; | |
const int *ciphersuites; | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse client hello v2" ) ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "client hello v2 illegal for renegotiation" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
#endif /* MBEDTLS_SSL_RENEGOTIATION */ | |
buf = ssl->in_hdr; | |
MBEDTLS_SSL_DEBUG_BUF( 4, "record header", buf, 5 ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v2, message type: %d", | |
buf[2] ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v2, message len.: %d", | |
( ( buf[0] & 0x7F ) << 8 ) | buf[1] ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v2, max. version: [%d:%d]", | |
buf[3], buf[4] ) ); | |
/* | |
* SSLv2 Client Hello | |
* | |
* Record layer: | |
* 0 . 1 message length | |
* | |
* SSL layer: | |
* 2 . 2 message type | |
* 3 . 4 protocol version | |
*/ | |
if( buf[2] != MBEDTLS_SSL_HS_CLIENT_HELLO || | |
buf[3] != MBEDTLS_SSL_MAJOR_VERSION_3 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
n = ( ( buf[0] << 8 ) | buf[1] ) & 0x7FFF; | |
if( n < 17 || n > 512 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->major_ver = MBEDTLS_SSL_MAJOR_VERSION_3; | |
ssl->minor_ver = ( buf[4] <= ssl->conf->max_minor_ver ) | |
? buf[4] : ssl->conf->max_minor_ver; | |
if( ssl->minor_ver < ssl->conf->min_minor_ver ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "client only supports ssl smaller than minimum" | |
" [%d:%d] < [%d:%d]", | |
ssl->major_ver, ssl->minor_ver, | |
ssl->conf->min_major_ver, ssl->conf->min_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 ); | |
} | |
ssl->handshake->max_major_ver = buf[3]; | |
ssl->handshake->max_minor_ver = buf[4]; | |
if( ( ret = mbedtls_ssl_fetch_input( ssl, 2 + n ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret ); | |
return( ret ); | |
} | |
ssl->handshake->update_checksum( ssl, buf + 2, n ); | |
buf = ssl->in_msg; | |
n = ssl->in_left - 5; | |
/* | |
* 0 . 1 ciphersuitelist length | |
* 2 . 3 session id length | |
* 4 . 5 challenge length | |
* 6 . .. ciphersuitelist | |
* .. . .. session id | |
* .. . .. challenge | |
*/ | |
MBEDTLS_SSL_DEBUG_BUF( 4, "record contents", buf, n ); | |
ciph_len = ( buf[0] << 8 ) | buf[1]; | |
sess_len = ( buf[2] << 8 ) | buf[3]; | |
chal_len = ( buf[4] << 8 ) | buf[5]; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciph_len: %d, sess_len: %d, chal_len: %d", | |
ciph_len, sess_len, chal_len ) ); | |
/* | |
* Make sure each parameter length is valid | |
*/ | |
if( ciph_len < 3 || ( ciph_len % 3 ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
if( sess_len > 32 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
if( chal_len < 8 || chal_len > 32 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
if( n != 6 + ciph_len + sess_len + chal_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, ciphersuitelist", | |
buf + 6, ciph_len ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, session id", | |
buf + 6 + ciph_len, sess_len ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, challenge", | |
buf + 6 + ciph_len + sess_len, chal_len ); | |
p = buf + 6 + ciph_len; | |
ssl->session_negotiate->id_len = sess_len; | |
memset( ssl->session_negotiate->id, 0, | |
sizeof( ssl->session_negotiate->id ) ); | |
memcpy( ssl->session_negotiate->id, p, ssl->session_negotiate->id_len ); | |
p += sess_len; | |
memset( ssl->handshake->randbytes, 0, 64 ); | |
memcpy( ssl->handshake->randbytes + 32 - chal_len, p, chal_len ); | |
/* | |
* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV | |
*/ | |
for( i = 0, p = buf + 6; i < ciph_len; i += 3, p += 3 ) | |
{ | |
if( p[0] == 0 && p[1] == 0 && p[2] == MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "received TLS_EMPTY_RENEGOTIATION_INFO " ) ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "received RENEGOTIATION SCSV " | |
"during renegotiation" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
#endif /* MBEDTLS_SSL_RENEGOTIATION */ | |
ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION; | |
break; | |
} | |
} | |
#if defined(MBEDTLS_SSL_FALLBACK_SCSV) | |
for( i = 0, p = buf + 6; i < ciph_len; i += 3, p += 3 ) | |
{ | |
if( p[0] == 0 && | |
p[1] == (unsigned char)( ( MBEDTLS_SSL_FALLBACK_SCSV_VALUE >> 8 ) & 0xff ) && | |
p[2] == (unsigned char)( ( MBEDTLS_SSL_FALLBACK_SCSV_VALUE ) & 0xff ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "received FALLBACK_SCSV" ) ); | |
if( ssl->minor_ver < ssl->conf->max_minor_ver ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "inapropriate fallback" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
break; | |
} | |
} | |
#endif /* MBEDTLS_SSL_FALLBACK_SCSV */ | |
got_common_suite = 0; | |
ciphersuites = ssl->conf->ciphersuite_list[ssl->minor_ver]; | |
ciphersuite_info = NULL; | |
#if defined(MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE) | |
for( j = 0, p = buf + 6; j < ciph_len; j += 3, p += 3 ) | |
for( i = 0; ciphersuites[i] != 0; i++ ) | |
#else | |
for( i = 0; ciphersuites[i] != 0; i++ ) | |
for( j = 0, p = buf + 6; j < ciph_len; j += 3, p += 3 ) | |
#endif | |
{ | |
if( p[0] != 0 || | |
p[1] != ( ( ciphersuites[i] >> 8 ) & 0xFF ) || | |
p[2] != ( ( ciphersuites[i] ) & 0xFF ) ) | |
continue; | |
got_common_suite = 1; | |
if( ( ret = ssl_ciphersuite_match( ssl, ciphersuites[i], | |
&ciphersuite_info ) ) != 0 ) | |
return( ret ); | |
if( ciphersuite_info != NULL ) | |
goto have_ciphersuite_v2; | |
} | |
if( got_common_suite ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got ciphersuites in common, " | |
"but none of them usable" ) ); | |
return( MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE ); | |
} | |
else | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) ); | |
return( MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN ); | |
} | |
have_ciphersuite_v2: | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "selected ciphersuite: %s", ciphersuite_info->name ) ); | |
ssl->session_negotiate->ciphersuite = ciphersuites[i]; | |
ssl->handshake->ciphersuite_info = ciphersuite_info; | |
/* | |
* SSLv2 Client Hello relevant 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" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->in_left = 0; | |
ssl->state++; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse client hello v2" ) ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO */ | |
/* This function doesn't alert on errors that happen early during | |
ClientHello parsing because they might indicate that the client is | |
not talking SSL/TLS at all and would not understand our alert. */ | |
static int ssl_parse_client_hello( mbedtls_ssl_context *ssl ) | |
{ | |
int ret, got_common_suite; | |
size_t i, j; | |
size_t ciph_offset, comp_offset, ext_offset; | |
size_t msg_len, ciph_len, sess_len, comp_len, ext_len; | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
size_t cookie_offset, cookie_len; | |
#endif | |
unsigned char *buf, *p, *ext; | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
int renegotiation_info_seen = 0; | |
#endif | |
int handshake_failure = 0; | |
const int *ciphersuites; | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info; | |
int major, minor; | |
/* If there is no signature-algorithm extension present, | |
* we need to fall back to the default values for allowed | |
* signature-hash pairs. */ | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
int sig_hash_alg_ext_present = 0; | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && | |
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse client hello" ) ); | |
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) | |
read_record_header: | |
#endif | |
/* | |
* If renegotiating, then the input was read with mbedtls_ssl_read_record(), | |
* otherwise read it ourselves manually in order to support SSLv2 | |
* ClientHello, which doesn't use the same record layer format. | |
*/ | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE ) | |
#endif | |
{ | |
if( ( ret = mbedtls_ssl_fetch_input( ssl, 5 ) ) != 0 ) | |
{ | |
/* No alert on a read error. */ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret ); | |
return( ret ); | |
} | |
} | |
buf = ssl->in_hdr; | |
#if defined(MBEDTLS_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO) | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_STREAM ) | |
#endif | |
if( ( buf[0] & 0x80 ) != 0 ) | |
return( ssl_parse_client_hello_v2( ssl ) ); | |
#endif | |
MBEDTLS_SSL_DEBUG_BUF( 4, "record header", buf, mbedtls_ssl_in_hdr_len( ssl ) ); | |
/* | |
* SSLv3/TLS Client Hello | |
* | |
* Record layer: | |
* 0 . 0 message type | |
* 1 . 2 protocol version | |
* 3 . 11 DTLS: epoch + record sequence number | |
* 3 . 4 message length | |
*/ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, message type: %d", | |
buf[0] ) ); | |
if( buf[0] != MBEDTLS_SSL_MSG_HANDSHAKE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, message len.: %d", | |
( ssl->in_len[0] << 8 ) | ssl->in_len[1] ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, protocol version: [%d:%d]", | |
buf[1], buf[2] ) ); | |
mbedtls_ssl_read_version( &major, &minor, ssl->conf->transport, buf + 1 ); | |
/* According to RFC 5246 Appendix E.1, the version here is typically | |
* "{03,00}, the lowest version number supported by the client, [or] the | |
* value of ClientHello.client_version", so the only meaningful check here | |
* is the major version shouldn't be less than 3 */ | |
if( major < MBEDTLS_SSL_MAJOR_VERSION_3 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* For DTLS if this is the initial handshake, remember the client sequence | |
* number to use it in our next message (RFC 6347 4.2.1) */ | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
&& ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE | |
#endif | |
) | |
{ | |
/* Epoch should be 0 for initial handshakes */ | |
if( ssl->in_ctr[0] != 0 || ssl->in_ctr[1] != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
memcpy( ssl->cur_out_ctr + 2, ssl->in_ctr + 2, 6 ); | |
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) | |
if( mbedtls_ssl_dtls_replay_check( ssl ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "replayed record, discarding" ) ); | |
ssl->next_record_offset = 0; | |
ssl->in_left = 0; | |
goto read_record_header; | |
} | |
/* No MAC to check yet, so we can update right now */ | |
mbedtls_ssl_dtls_replay_update( ssl ); | |
#endif | |
} | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
msg_len = ( ssl->in_len[0] << 8 ) | ssl->in_len[1]; | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ) | |
{ | |
/* Set by mbedtls_ssl_read_record() */ | |
msg_len = ssl->in_hslen; | |
} | |
else | |
#endif | |
{ | |
if( msg_len > MBEDTLS_SSL_IN_CONTENT_LEN ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
if( ( ret = mbedtls_ssl_fetch_input( ssl, | |
mbedtls_ssl_in_hdr_len( ssl ) + msg_len ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_fetch_input", ret ); | |
return( ret ); | |
} | |
/* Done reading this record, get ready for the next one */ | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
ssl->next_record_offset = msg_len + mbedtls_ssl_in_hdr_len( ssl ); | |
else | |
#endif | |
ssl->in_left = 0; | |
} | |
buf = ssl->in_msg; | |
MBEDTLS_SSL_DEBUG_BUF( 4, "record contents", buf, msg_len ); | |
ssl->handshake->update_checksum( ssl, buf, msg_len ); | |
/* | |
* Handshake layer: | |
* 0 . 0 handshake type | |
* 1 . 3 handshake length | |
* 4 . 5 DTLS only: message seqence number | |
* 6 . 8 DTLS only: fragment offset | |
* 9 . 11 DTLS only: fragment length | |
*/ | |
if( msg_len < mbedtls_ssl_hs_hdr_len( ssl ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, handshake type: %d", buf[0] ) ); | |
if( buf[0] != MBEDTLS_SSL_HS_CLIENT_HELLO ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, handshake len.: %d", | |
( buf[1] << 16 ) | ( buf[2] << 8 ) | buf[3] ) ); | |
/* We don't support fragmentation of ClientHello (yet?) */ | |
if( buf[1] != 0 || | |
msg_len != mbedtls_ssl_hs_hdr_len( ssl ) + ( ( buf[2] << 8 ) | buf[3] ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
{ | |
/* | |
* Copy the client's handshake message_seq on initial handshakes, | |
* check sequence number on renego. | |
*/ | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS ) | |
{ | |
/* This couldn't be done in ssl_prepare_handshake_record() */ | |
unsigned int cli_msg_seq = ( ssl->in_msg[4] << 8 ) | | |
ssl->in_msg[5]; | |
if( cli_msg_seq != ssl->handshake->in_msg_seq ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message_seq: " | |
"%d (expected %d)", cli_msg_seq, | |
ssl->handshake->in_msg_seq ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ssl->handshake->in_msg_seq++; | |
} | |
else | |
#endif | |
{ | |
unsigned int cli_msg_seq = ( ssl->in_msg[4] << 8 ) | | |
ssl->in_msg[5]; | |
ssl->handshake->out_msg_seq = cli_msg_seq; | |
ssl->handshake->in_msg_seq = cli_msg_seq + 1; | |
} | |
/* | |
* For now we don't support fragmentation, so make sure | |
* fragment_offset == 0 and fragment_length == length | |
*/ | |
if( ssl->in_msg[6] != 0 || ssl->in_msg[7] != 0 || ssl->in_msg[8] != 0 || | |
memcmp( ssl->in_msg + 1, ssl->in_msg + 9, 3 ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "ClientHello fragmentation not supported" ) ); | |
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); | |
} | |
} | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
buf += mbedtls_ssl_hs_hdr_len( ssl ); | |
msg_len -= mbedtls_ssl_hs_hdr_len( ssl ); | |
/* | |
* ClientHello layer: | |
* 0 . 1 protocol version | |
* 2 . 33 random bytes (starting with 4 bytes of Unix time) | |
* 34 . 35 session id length (1 byte) | |
* 35 . 34+x session id | |
* 35+x . 35+x DTLS only: cookie length (1 byte) | |
* 36+x . .. DTLS only: cookie | |
* .. . .. ciphersuite list length (2 bytes) | |
* .. . .. ciphersuite list | |
* .. . .. compression alg. list length (1 byte) | |
* .. . .. compression alg. list | |
* .. . .. extensions length (2 bytes, optional) | |
* .. . .. extensions (optional) | |
*/ | |
/* | |
* Minimal length (with everything empty and extensions omitted) is | |
* 2 + 32 + 1 + 2 + 1 = 38 bytes. Check that first, so that we can | |
* read at least up to session id length without worrying. | |
*/ | |
if( msg_len < 38 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* | |
* Check and save the protocol version | |
*/ | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, version", buf, 2 ); | |
mbedtls_ssl_read_version( &ssl->major_ver, &ssl->minor_ver, | |
ssl->conf->transport, buf ); | |
ssl->handshake->max_major_ver = ssl->major_ver; | |
ssl->handshake->max_minor_ver = ssl->minor_ver; | |
if( ssl->major_ver < ssl->conf->min_major_ver || | |
ssl->minor_ver < ssl->conf->min_minor_ver ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "client only supports ssl smaller than minimum" | |
" [%d:%d] < [%d:%d]", | |
ssl->major_ver, ssl->minor_ver, | |
ssl->conf->min_major_ver, ssl->conf->min_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( ssl->major_ver > ssl->conf->max_major_ver ) | |
{ | |
ssl->major_ver = ssl->conf->max_major_ver; | |
ssl->minor_ver = ssl->conf->max_minor_ver; | |
} | |
else if( ssl->minor_ver > ssl->conf->max_minor_ver ) | |
ssl->minor_ver = ssl->conf->max_minor_ver; | |
/* | |
* Save client random (inc. Unix time) | |
*/ | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, random bytes", buf + 2, 32 ); | |
memcpy( ssl->handshake->randbytes, buf + 2, 32 ); | |
/* | |
* Check the session ID length and save session ID | |
*/ | |
sess_len = buf[34]; | |
if( sess_len > sizeof( ssl->session_negotiate->id ) || | |
sess_len + 34 + 2 > msg_len ) /* 2 for cipherlist length field */ | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, session id", buf + 35, sess_len ); | |
ssl->session_negotiate->id_len = sess_len; | |
memset( ssl->session_negotiate->id, 0, | |
sizeof( ssl->session_negotiate->id ) ); | |
memcpy( ssl->session_negotiate->id, buf + 35, | |
ssl->session_negotiate->id_len ); | |
/* | |
* Check the cookie length and content | |
*/ | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
{ | |
cookie_offset = 35 + sess_len; | |
cookie_len = buf[cookie_offset]; | |
if( cookie_offset + 1 + cookie_len + 2 > msg_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, cookie", | |
buf + cookie_offset + 1, cookie_len ); | |
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) | |
if( ssl->conf->f_cookie_check != NULL | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
&& ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE | |
#endif | |
) | |
{ | |
if( ssl->conf->f_cookie_check( ssl->conf->p_cookie, | |
buf + cookie_offset + 1, cookie_len, | |
ssl->cli_id, ssl->cli_id_len ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "cookie verification failed" ) ); | |
ssl->handshake->verify_cookie_len = 1; | |
} | |
else | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "cookie verification passed" ) ); | |
ssl->handshake->verify_cookie_len = 0; | |
} | |
} | |
else | |
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */ | |
{ | |
/* We know we didn't send a cookie, so it should be empty */ | |
if( cookie_len != 0 ) | |
{ | |
/* This may be an attacker's probe, so don't send an alert */ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "cookie verification skipped" ) ); | |
} | |
/* | |
* Check the ciphersuitelist length (will be parsed later) | |
*/ | |
ciph_offset = cookie_offset + 1 + cookie_len; | |
} | |
else | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
ciph_offset = 35 + sess_len; | |
ciph_len = ( buf[ciph_offset + 0] << 8 ) | |
| ( buf[ciph_offset + 1] ); | |
if( ciph_len < 2 || | |
ciph_len + 2 + ciph_offset + 1 > msg_len || /* 1 for comp. alg. len */ | |
( ciph_len % 2 ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, ciphersuitelist", | |
buf + ciph_offset + 2, ciph_len ); | |
/* | |
* Check the compression algorithms length and pick one | |
*/ | |
comp_offset = ciph_offset + 2 + ciph_len; | |
comp_len = buf[comp_offset]; | |
if( comp_len < 1 || | |
comp_len > 16 || | |
comp_len + comp_offset + 1 > msg_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, compression", | |
buf + comp_offset + 1, comp_len ); | |
ssl->session_negotiate->compression = MBEDTLS_SSL_COMPRESS_NULL; | |
#if defined(MBEDTLS_ZLIB_SUPPORT) | |
for( i = 0; i < comp_len; ++i ) | |
{ | |
if( buf[comp_offset + 1 + i] == MBEDTLS_SSL_COMPRESS_DEFLATE ) | |
{ | |
ssl->session_negotiate->compression = MBEDTLS_SSL_COMPRESS_DEFLATE; | |
break; | |
} | |
} | |
#endif | |
/* See comments in ssl_write_client_hello() */ | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
ssl->session_negotiate->compression = MBEDTLS_SSL_COMPRESS_NULL; | |
#endif | |
/* Do not parse the extensions if the protocol is SSLv3 */ | |
#if defined(MBEDTLS_SSL_PROTO_SSL3) | |
if( ( ssl->major_ver != 3 ) || ( ssl->minor_ver != 0 ) ) | |
{ | |
#endif | |
/* | |
* Check the extension length | |
*/ | |
ext_offset = comp_offset + 1 + comp_len; | |
if( msg_len > ext_offset ) | |
{ | |
if( msg_len < ext_offset + 2 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ext_len = ( buf[ext_offset + 0] << 8 ) | |
| ( buf[ext_offset + 1] ); | |
if( ( ext_len > 0 && ext_len < 4 ) || | |
msg_len != ext_offset + 2 + ext_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
} | |
else | |
ext_len = 0; | |
ext = buf + ext_offset + 2; | |
MBEDTLS_SSL_DEBUG_BUF( 3, "client hello extensions", ext, ext_len ); | |
while( ext_len != 0 ) | |
{ | |
unsigned int ext_id; | |
unsigned int ext_size; | |
if ( ext_len < 4 ) { | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
ext_id = ( ( ext[0] << 8 ) | ( ext[1] ) ); | |
ext_size = ( ( ext[2] << 8 ) | ( ext[3] ) ); | |
if( ext_size + 4 > ext_len ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
switch( ext_id ) | |
{ | |
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | |
case MBEDTLS_TLS_EXT_SERVERNAME: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found ServerName extension" ) ); | |
if( ssl->conf->f_sni == NULL ) | |
break; | |
ret = ssl_parse_servername_ext( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ | |
case MBEDTLS_TLS_EXT_RENEGOTIATION_INFO: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found renegotiation extension" ) ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
renegotiation_info_seen = 1; | |
#endif | |
ret = ssl_parse_renegotiation_info( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
case MBEDTLS_TLS_EXT_SIG_ALG: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found signature_algorithms extension" ) ); | |
ret = ssl_parse_signature_algorithms_ext( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
sig_hash_alg_ext_present = 1; | |
break; | |
#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) | |
case MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found supported elliptic curves extension" ) ); | |
ret = ssl_parse_supported_elliptic_curves( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
case MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found supported point formats extension" ) ); | |
ssl->handshake->cli_exts |= MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS_PRESENT; | |
ret = ssl_parse_supported_point_formats( ssl, ext + 4, ext_size ); | |
if( ret != 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" ) ); | |
ret = ssl_parse_ecjpake_kkpp( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ | |
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) | |
case MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found max fragment length extension" ) ); | |
ret = ssl_parse_max_fragment_length_ext( ssl, ext + 4, ext_size ); | |
if( ret != 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" ) ); | |
ret = ssl_parse_truncated_hmac_ext( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ | |
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | |
case MBEDTLS_TLS_EXT_CID: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found CID extension" ) ); | |
ret = ssl_parse_cid_ext( ssl, ext + 4, ext_size ); | |
if( ret != 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" ) ); | |
ret = ssl_parse_encrypt_then_mac_ext( ssl, ext + 4, ext_size ); | |
if( ret != 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" ) ); | |
ret = ssl_parse_extended_ms_ext( ssl, ext + 4, ext_size ); | |
if( ret != 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" ) ); | |
ret = ssl_parse_session_ticket_ext( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
#if defined(MBEDTLS_SSL_ALPN) | |
case MBEDTLS_TLS_EXT_ALPN: | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "found alpn extension" ) ); | |
ret = ssl_parse_alpn_ext( ssl, ext + 4, ext_size ); | |
if( ret != 0 ) | |
return( ret ); | |
break; | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
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 client hello message" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
} | |
#if defined(MBEDTLS_SSL_PROTO_SSL3) | |
} | |
#endif | |
#if defined(MBEDTLS_SSL_FALLBACK_SCSV) | |
for( i = 0, p = buf + ciph_offset + 2; i < ciph_len; i += 2, p += 2 ) | |
{ | |
if( p[0] == (unsigned char)( ( MBEDTLS_SSL_FALLBACK_SCSV_VALUE >> 8 ) & 0xff ) && | |
p[1] == (unsigned char)( ( MBEDTLS_SSL_FALLBACK_SCSV_VALUE ) & 0xff ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "received FALLBACK_SCSV" ) ); | |
if( ssl->minor_ver < ssl->conf->max_minor_ver ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "inapropriate fallback" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
break; | |
} | |
} | |
#endif /* MBEDTLS_SSL_FALLBACK_SCSV */ | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
/* | |
* Try to fall back to default hash SHA1 if the client | |
* hasn't provided any preferred signature-hash combinations. | |
*/ | |
if( sig_hash_alg_ext_present == 0 ) | |
{ | |
mbedtls_md_type_t md_default = MBEDTLS_MD_SHA1; | |
if( mbedtls_ssl_check_sig_hash( ssl, md_default ) != 0 ) | |
md_default = MBEDTLS_MD_NONE; | |
mbedtls_ssl_sig_hash_set_const_hash( &ssl->handshake->hash_algs, md_default ); | |
} | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 && | |
MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ | |
/* | |
* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV | |
*/ | |
for( i = 0, p = buf + ciph_offset + 2; i < ciph_len; i += 2, p += 2 ) | |
{ | |
if( p[0] == 0 && p[1] == MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "received TLS_EMPTY_RENEGOTIATION_INFO " ) ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "received RENEGOTIATION SCSV " | |
"during renegotiation" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
#endif | |
ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION; | |
break; | |
} | |
} | |
/* | |
* Renegotiation security checks | |
*/ | |
if( ssl->secure_renegotiation != MBEDTLS_SSL_SECURE_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 ) | |
{ | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO ); | |
} | |
/* | |
* Search for a matching ciphersuite | |
* (At the end because we need information from the EC-based extensions | |
* and certificate from the SNI callback triggered by the SNI extension.) | |
*/ | |
got_common_suite = 0; | |
ciphersuites = ssl->conf->ciphersuite_list[ssl->minor_ver]; | |
ciphersuite_info = NULL; | |
#if defined(MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE) | |
for( j = 0, p = buf + ciph_offset + 2; j < ciph_len; j += 2, p += 2 ) | |
for( i = 0; ciphersuites[i] != 0; i++ ) | |
#else | |
for( i = 0; ciphersuites[i] != 0; i++ ) | |
for( j = 0, p = buf + ciph_offset + 2; j < ciph_len; j += 2, p += 2 ) | |
#endif | |
{ | |
if( p[0] != ( ( ciphersuites[i] >> 8 ) & 0xFF ) || | |
p[1] != ( ( ciphersuites[i] ) & 0xFF ) ) | |
continue; | |
got_common_suite = 1; | |
if( ( ret = ssl_ciphersuite_match( ssl, ciphersuites[i], | |
&ciphersuite_info ) ) != 0 ) | |
return( ret ); | |
if( ciphersuite_info != NULL ) | |
goto have_ciphersuite; | |
} | |
if( got_common_suite ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got ciphersuites in common, " | |
"but none of them usable" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE ); | |
} | |
else | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); | |
return( MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN ); | |
} | |
have_ciphersuite: | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "selected ciphersuite: %s", ciphersuite_info->name ) ); | |
ssl->session_negotiate->ciphersuite = ciphersuites[i]; | |
ssl->handshake->ciphersuite_info = ciphersuite_info; | |
ssl->state++; | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) | |
mbedtls_ssl_recv_flight_completed( ssl ); | |
#endif | |
/* Debugging-only output for testsuite */ | |
#if defined(MBEDTLS_DEBUG_C) && \ | |
defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ | |
defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) | |
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) | |
{ | |
mbedtls_pk_type_t sig_alg = mbedtls_ssl_get_ciphersuite_sig_alg( ciphersuite_info ); | |
if( sig_alg != MBEDTLS_PK_NONE ) | |
{ | |
mbedtls_md_type_t md_alg = mbedtls_ssl_sig_hash_set_find( &ssl->handshake->hash_algs, | |
sig_alg ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello v3, signature_algorithm ext: %d", | |
mbedtls_ssl_hash_from_md_alg( md_alg ) ) ); | |
} | |
else | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no hash algorithm for signature algorithm " | |
"%d - should not happen", sig_alg ) ); | |
} | |
} | |
#endif | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse client hello" ) ); | |
return( 0 ); | |
} | |
#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; | |
if( ssl->session_negotiate->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding truncated hmac extension" ) ); | |
*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_DTLS_CONNECTION_ID) | |
static void ssl_write_cid_ext( mbedtls_ssl_context *ssl, | |
unsigned char *buf, | |
size_t *olen ) | |
{ | |
unsigned char *p = buf; | |
size_t ext_len; | |
const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN; | |
*olen = 0; | |
/* Skip writing the extension if we don't want to use it or if | |
* the client hasn't offered it. */ | |
if( ssl->handshake->cid_in_use == MBEDTLS_SSL_CID_DISABLED ) | |
return; | |
/* ssl->own_cid_len is at most MBEDTLS_SSL_CID_IN_LEN_MAX | |
* which is at most 255, so the increment cannot overflow. */ | |
if( end < p || (size_t)( end - p ) < (unsigned)( ssl->own_cid_len + 5 ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) ); | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding CID extension" ) ); | |
/* | |
* Quoting draft-ietf-tls-dtls-connection-id-05 | |
* https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05 | |
* | |
* struct { | |
* opaque cid<0..2^8-1>; | |
* } ConnectionId; | |
*/ | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_CID >> 8 ) & 0xFF ); | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_CID ) & 0xFF ); | |
ext_len = (size_t) ssl->own_cid_len + 1; | |
*p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF ); | |
*p++ = (unsigned char)( ( ext_len ) & 0xFF ); | |
*p++ = (uint8_t) ssl->own_cid_len; | |
memcpy( p, ssl->own_cid, ssl->own_cid_len ); | |
*olen = ssl->own_cid_len + 5; | |
} | |
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | |
#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 mbedtls_ssl_ciphersuite_t *suite = NULL; | |
const mbedtls_cipher_info_t *cipher = NULL; | |
if( ssl->session_negotiate->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED || | |
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ) | |
{ | |
*olen = 0; | |
return; | |
} | |
/* | |
* RFC 7366: "If a server receives an encrypt-then-MAC request extension | |
* from a client and then selects a stream or Authenticated Encryption | |
* with Associated Data (AEAD) ciphersuite, it MUST NOT send an | |
* encrypt-then-MAC response extension back to the client." | |
*/ | |
if( ( suite = mbedtls_ssl_ciphersuite_from_id( | |
ssl->session_negotiate->ciphersuite ) ) == NULL || | |
( cipher = mbedtls_cipher_info_from_type( suite->cipher ) ) == NULL || | |
cipher->mode != MBEDTLS_MODE_CBC ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding encrypt then mac extension" ) ); | |
*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; | |
if( ssl->handshake->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED || | |
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding extended master secret " | |
"extension" ) ); | |
*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; | |
if( ssl->handshake->new_session_ticket == 0 ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding session ticket extension" ) ); | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET >> 8 ) & 0xFF ); | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET ) & 0xFF ); | |
*p++ = 0x00; | |
*p++ = 0x00; | |
*olen = 4; | |
} | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
static void ssl_write_renegotiation_ext( mbedtls_ssl_context *ssl, | |
unsigned char *buf, | |
size_t *olen ) | |
{ | |
unsigned char *p = buf; | |
if( ssl->secure_renegotiation != MBEDTLS_SSL_SECURE_RENEGOTIATION ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, secure renegotiation extension" ) ); | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF ); | |
*p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO ) & 0xFF ); | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
if( ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ) | |
{ | |
*p++ = 0x00; | |
*p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF; | |
*p++ = ssl->verify_data_len * 2 & 0xFF; | |
memcpy( p, ssl->peer_verify_data, ssl->verify_data_len ); | |
p += ssl->verify_data_len; | |
memcpy( p, ssl->own_verify_data, ssl->verify_data_len ); | |
p += ssl->verify_data_len; | |
} | |
else | |
#endif /* MBEDTLS_SSL_RENEGOTIATION */ | |
{ | |
*p++ = 0x00; | |
*p++ = 0x01; | |
*p++ = 0x00; | |
} | |
*olen = p - buf; | |
} | |
#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; | |
if( ssl->session_negotiate->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, max_fragment_length extension" ) ); | |
*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->session_negotiate->mfl_code; | |
*olen = 5; | |
} | |
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ | |
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ | |
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) | |
static void ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl, | |
unsigned char *buf, | |
size_t *olen ) | |
{ | |
unsigned char *p = buf; | |
((void) ssl); | |
if( ( ssl->handshake->cli_exts & | |
MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS_PRESENT ) == 0 ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, supported_point_formats extension" ) ); | |
*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_OUT_CONTENT_LEN; | |
size_t kkpp_len; | |
*olen = 0; | |
/* Skip costly computation if not needed */ | |
if( ssl->handshake->ciphersuite_info->key_exchange != | |
MBEDTLS_KEY_EXCHANGE_ECJPAKE ) | |
return; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, 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 ); | |
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; | |
} | |
*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_ALPN ) | |
static void ssl_write_alpn_ext( mbedtls_ssl_context *ssl, | |
unsigned char *buf, size_t *olen ) | |
{ | |
if( ssl->alpn_chosen == NULL ) | |
{ | |
*olen = 0; | |
return; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding alpn extension" ) ); | |
/* | |
* 0 . 1 ext identifier | |
* 2 . 3 ext length | |
* 4 . 5 protocol list length | |
* 6 . 6 protocol name length | |
* 7 . 7+n protocol name | |
*/ | |
buf[0] = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN >> 8 ) & 0xFF ); | |
buf[1] = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN ) & 0xFF ); | |
*olen = 7 + strlen( ssl->alpn_chosen ); | |
buf[2] = (unsigned char)( ( ( *olen - 4 ) >> 8 ) & 0xFF ); | |
buf[3] = (unsigned char)( ( ( *olen - 4 ) ) & 0xFF ); | |
buf[4] = (unsigned char)( ( ( *olen - 6 ) >> 8 ) & 0xFF ); | |
buf[5] = (unsigned char)( ( ( *olen - 6 ) ) & 0xFF ); | |
buf[6] = (unsigned char)( ( ( *olen - 7 ) ) & 0xFF ); | |
memcpy( buf + 7, ssl->alpn_chosen, *olen - 7 ); | |
} | |
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C */ | |
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) | |
static int ssl_write_hello_verify_request( mbedtls_ssl_context *ssl ) | |
{ | |
int ret; | |
unsigned char *p = ssl->out_msg + 4; | |
unsigned char *cookie_len_byte; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write hello verify request" ) ); | |
/* | |
* struct { | |
* ProtocolVersion server_version; | |
* opaque cookie<0..2^8-1>; | |
* } HelloVerifyRequest; | |
*/ | |
/* The RFC is not clear on this point, but sending the actual negotiated | |
* version looks like the most interoperable thing to do. */ | |
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver, | |
ssl->conf->transport, p ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "server version", p, 2 ); | |
p += 2; | |
/* If we get here, f_cookie_check is not null */ | |
if( ssl->conf->f_cookie_write == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "inconsistent cookie callbacks" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
/* Skip length byte until we know the length */ | |
cookie_len_byte = p++; | |
if( ( ret = ssl->conf->f_cookie_write( ssl->conf->p_cookie, | |
&p, ssl->out_buf + MBEDTLS_SSL_OUT_BUFFER_LEN, | |
ssl->cli_id, ssl->cli_id_len ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "f_cookie_write", ret ); | |
return( ret ); | |
} | |
*cookie_len_byte = (unsigned char)( p - ( cookie_len_byte + 1 ) ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "cookie sent", cookie_len_byte + 1, *cookie_len_byte ); | |
ssl->out_msglen = p - ssl->out_msg; | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST; | |
ssl->state = MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT; | |
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && | |
( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flight_transmit", ret ); | |
return( ret ); | |
} | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write hello verify request" ) ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */ | |
static int ssl_write_server_hello( mbedtls_ssl_context *ssl ) | |
{ | |
#if defined(MBEDTLS_HAVE_TIME) | |
mbedtls_time_t t; | |
#endif | |
int ret; | |
size_t olen, ext_len = 0, n; | |
unsigned char *buf, *p; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write server hello" ) ); | |
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && | |
ssl->handshake->verify_cookie_len != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "client hello was not authenticated" ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write server hello" ) ); | |
return( ssl_write_hello_verify_request( ssl ) ); | |
} | |
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */ | |
if( ssl->conf->f_rng == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no RNG provided") ); | |
return( MBEDTLS_ERR_SSL_NO_RNG ); | |
} | |
/* | |
* 0 . 0 handshake type | |
* 1 . 3 handshake length | |
* 4 . 5 protocol version | |
* 6 . 9 UNIX time() | |
* 10 . 37 random bytes | |
*/ | |
buf = ssl->out_msg; | |
p = buf + 4; | |
mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver, | |
ssl->conf->transport, p ); | |
p += 2; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen version: [%d:%d]", | |
buf[4], buf[5] ) ); | |
#if defined(MBEDTLS_HAVE_TIME) | |
t = mbedtls_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, ( "server 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 ); | |
p += 28; | |
memcpy( ssl->handshake->randbytes + 32, buf + 6, 32 ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 6, 32 ); | |
/* | |
* Resume is 0 by default, see ssl_handshake_init(). | |
* It may be already set to 1 by ssl_parse_session_ticket_ext(). | |
* If not, try looking up session ID in our cache. | |
*/ | |
if( ssl->handshake->resume == 0 && | |
#if defined(MBEDTLS_SSL_RENEGOTIATION) | |
ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE && | |
#endif | |
ssl->session_negotiate->id_len != 0 && | |
ssl->conf->f_get_cache != NULL && | |
ssl->conf->f_get_cache( ssl->conf->p_cache, ssl->session_negotiate ) == 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "session successfully restored from cache" ) ); | |
ssl->handshake->resume = 1; | |
} | |
if( ssl->handshake->resume == 0 ) | |
{ | |
/* | |
* New session, create a new session id, | |
* unless we're about to issue a session ticket | |
*/ | |
ssl->state++; | |
#if defined(MBEDTLS_HAVE_TIME) | |
ssl->session_negotiate->start = mbedtls_time( NULL ); | |
#endif | |
#if defined(MBEDTLS_SSL_SESSION_TICKETS) | |
if( ssl->handshake->new_session_ticket != 0 ) | |
{ | |
ssl->session_negotiate->id_len = n = 0; | |
memset( ssl->session_negotiate->id, 0, 32 ); | |
} | |
else | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
{ | |
ssl->session_negotiate->id_len = n = 32; | |
if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, ssl->session_negotiate->id, | |
n ) ) != 0 ) | |
return( ret ); | |
} | |
} | |
else | |
{ | |
/* | |
* Resuming a session | |
*/ | |
n = ssl->session_negotiate->id_len; | |
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 ); | |
} | |
} | |
/* | |
* 38 . 38 session id length | |
* 39 . 38+n session id | |
* 39+n . 40+n chosen ciphersuite | |
* 41+n . 41+n chosen compression alg. | |
* 42+n . 43+n extensions length | |
* 44+n . 43+n+m extensions | |
*/ | |
*p++ = (unsigned char) ssl->session_negotiate->id_len; | |
memcpy( p, ssl->session_negotiate->id, ssl->session_negotiate->id_len ); | |
p += ssl->session_negotiate->id_len; | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, session id", buf + 39, n ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "%s session has been resumed", | |
ssl->handshake->resume ? "a" : "no" ) ); | |
*p++ = (unsigned char)( ssl->session_negotiate->ciphersuite >> 8 ); | |
*p++ = (unsigned char)( ssl->session_negotiate->ciphersuite ); | |
*p++ = (unsigned char)( ssl->session_negotiate->compression ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %s", | |
mbedtls_ssl_get_ciphersuite_name( ssl->session_negotiate->ciphersuite ) ) ); | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: 0x%02X", | |
ssl->session_negotiate->compression ) ); | |
/* Do not write the extensions if the protocol is SSLv3 */ | |
#if defined(MBEDTLS_SSL_PROTO_SSL3) | |
if( ( ssl->major_ver != 3 ) || ( ssl->minor_ver != 0 ) ) | |
{ | |
#endif | |
/* | |
* First write extensions, then the total length | |
*/ | |
ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen ); | |
ext_len += olen; | |
#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_DTLS_CONNECTION_ID) | |
ssl_write_cid_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_SESSION_TICKETS) | |
ssl_write_session_ticket_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) | |
if ( mbedtls_ssl_ciphersuite_uses_ec( | |
mbedtls_ssl_ciphersuite_from_id( ssl->session_negotiate->ciphersuite ) ) ) | |
{ | |
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_ALPN) | |
ssl_write_alpn_ext( ssl, p + 2 + ext_len, &olen ); | |
ext_len += olen; | |
#endif | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server 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; | |
} | |
#if defined(MBEDTLS_SSL_PROTO_SSL3) | |
} | |
#endif | |
ssl->out_msglen = p - buf; | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_SERVER_HELLO; | |
ret = mbedtls_ssl_write_handshake_msg( ssl ); | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write server hello" ) ); | |
return( ret ); | |
} | |
#if !defined(MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED) | |
static int ssl_write_certificate_request( mbedtls_ssl_context *ssl ) | |
{ | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate request" ) ); | |
if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate request" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
#else /* !MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED */ | |
static int ssl_write_certificate_request( mbedtls_ssl_context *ssl ) | |
{ | |
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
size_t dn_size, total_dn_size; /* excluding length bytes */ | |
size_t ct_len, sa_len; /* including length bytes */ | |
unsigned char *buf, *p; | |
const unsigned char * const end = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN; | |
const mbedtls_x509_crt *crt; | |
int authmode; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate request" ) ); | |
ssl->state++; | |
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | |
if( ssl->handshake->sni_authmode != MBEDTLS_SSL_VERIFY_UNSET ) | |
authmode = ssl->handshake->sni_authmode; | |
else | |
#endif | |
authmode = ssl->conf->authmode; | |
if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) || | |
authmode == MBEDTLS_SSL_VERIFY_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate request" ) ); | |
return( 0 ); | |
} | |
/* | |
* 0 . 0 handshake type | |
* 1 . 3 handshake length | |
* 4 . 4 cert type count | |
* 5 .. m-1 cert types | |
* m .. m+1 sig alg length (TLS 1.2 only) | |
* m+1 .. n-1 SignatureAndHashAlgorithms (TLS 1.2 only) | |
* n .. n+1 length of all DNs | |
* n+2 .. n+3 length of DN 1 | |
* n+4 .. ... Distinguished Name #1 | |
* ... .. ... length of DN 2, etc. | |
*/ | |
buf = ssl->out_msg; | |
p = buf + 4; | |
/* | |
* Supported certificate types | |
* | |
* ClientCertificateType certificate_types<1..2^8-1>; | |
* enum { (255) } ClientCertificateType; | |
*/ | |
ct_len = 0; | |
#if defined(MBEDTLS_RSA_C) | |
p[1 + ct_len++] = MBEDTLS_SSL_CERT_TYPE_RSA_SIGN; | |
#endif | |
#if defined(MBEDTLS_ECDSA_C) | |
p[1 + ct_len++] = MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN; | |
#endif | |
p[0] = (unsigned char) ct_len++; | |
p += ct_len; | |
sa_len = 0; | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) | |
/* | |
* Add signature_algorithms for verify (TLS 1.2) | |
* | |
* SignatureAndHashAlgorithm supported_signature_algorithms<2..2^16-2>; | |
* | |
* struct { | |
* HashAlgorithm hash; | |
* SignatureAlgorithm signature; | |
* } SignatureAndHashAlgorithm; | |
* | |
* enum { (255) } HashAlgorithm; | |
* enum { (255) } SignatureAlgorithm; | |
*/ | |
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) | |
{ | |
const int *cur; | |
/* | |
* Supported signature algorithms | |
*/ | |
for( cur = ssl->conf->sig_hashes; *cur != MBEDTLS_MD_NONE; cur++ ) | |
{ | |
unsigned char hash = mbedtls_ssl_hash_from_md_alg( *cur ); | |
if( MBEDTLS_SSL_HASH_NONE == hash || mbedtls_ssl_set_calc_verify_md( ssl, hash ) ) | |
continue; | |
#if defined(MBEDTLS_RSA_C) | |
p[2 + sa_len++] = hash; | |
p[2 + sa_len++] = MBEDTLS_SSL_SIG_RSA; | |
#endif | |
#if defined(MBEDTLS_ECDSA_C) | |
p[2 + sa_len++] = hash; | |
p[2 + sa_len++] = MBEDTLS_SSL_SIG_ECDSA; | |
#endif | |
} | |
p[0] = (unsigned char)( sa_len >> 8 ); | |
p[1] = (unsigned char)( sa_len ); | |
sa_len += 2; | |
p += sa_len; | |
} | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ | |
/* | |
* DistinguishedName certificate_authorities<0..2^16-1>; | |
* opaque DistinguishedName<1..2^16-1>; | |
*/ | |
p += 2; | |
total_dn_size = 0; | |
if( ssl->conf->cert_req_ca_list == MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED ) | |
{ | |
/* NOTE: If trusted certificates are provisioned | |
* via a CA callback (configured through | |
* `mbedtls_ssl_conf_ca_cb()`, then the | |
* CertificateRequest is currently left empty. */ | |
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | |
if( ssl->handshake->sni_ca_chain != NULL ) | |
crt = ssl->handshake->sni_ca_chain; | |
else | |
#endif | |
crt = ssl->conf->ca_chain; | |
while( crt != NULL && crt->version != 0 ) | |
{ | |
dn_size = crt->subject_raw.len; | |
if( end < p || | |
(size_t)( end - p ) < dn_size || | |
(size_t)( end - p ) < 2 + dn_size ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "skipping CAs: buffer too short" ) ); | |
break; | |
} | |
*p++ = (unsigned char)( dn_size >> 8 ); | |
*p++ = (unsigned char)( dn_size ); | |
memcpy( p, crt->subject_raw.p, dn_size ); | |
p += dn_size; | |
MBEDTLS_SSL_DEBUG_BUF( 3, "requested DN", p - dn_size, dn_size ); | |
total_dn_size += 2 + dn_size; | |
crt = crt->next; | |
} | |
} | |
ssl->out_msglen = p - buf; | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_CERTIFICATE_REQUEST; | |
ssl->out_msg[4 + ct_len + sa_len] = (unsigned char)( total_dn_size >> 8 ); | |
ssl->out_msg[5 + ct_len + sa_len] = (unsigned char)( total_dn_size ); | |
ret = mbedtls_ssl_write_handshake_msg( ssl ); | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write certificate request" ) ); | |
return( ret ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED */ | |
#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; | |
if( ! mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_ECKEY ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "server key not ECDH capable" ) ); | |
return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH ); | |
} | |
if( ( ret = mbedtls_ecdh_get_params( &ssl->handshake->ecdh_ctx, | |
mbedtls_pk_ec( *mbedtls_ssl_own_key( ssl ) ), | |
MBEDTLS_ECDH_OURS ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_get_params" ), ret ); | |
return( ret ); | |
} | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || | |
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) && \ | |
defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
static int ssl_resume_server_key_exchange( mbedtls_ssl_context *ssl, | |
size_t *signature_len ) | |
{ | |
/* Append the signature to ssl->out_msg, leaving 2 bytes for the | |
* signature length which will be added in ssl_write_server_key_exchange | |
* after the call to ssl_prepare_server_key_exchange. | |
* ssl_write_server_key_exchange also takes care of incrementing | |
* ssl->out_msglen. */ | |
unsigned char *sig_start = ssl->out_msg + ssl->out_msglen + 2; | |
size_t sig_max_len = ( ssl->out_buf + MBEDTLS_SSL_OUT_CONTENT_LEN | |
- sig_start ); | |
int ret = ssl->conf->f_async_resume( ssl, | |
sig_start, signature_len, sig_max_len ); | |
if( ret != MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ) | |
{ | |
ssl->handshake->async_in_progress = 0; | |
mbedtls_ssl_set_async_operation_data( ssl, NULL ); | |
} | |
MBEDTLS_SSL_DEBUG_RET( 2, "ssl_resume_server_key_exchange", ret ); | |
return( ret ); | |
} | |
#endif /* defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) && | |
defined(MBEDTLS_SSL_ASYNC_PRIVATE) */ | |
/* Prepare the ServerKeyExchange message, up to and including | |
* calculating the signature if any, but excluding formatting the | |
* signature and sending the message. */ | |
static int ssl_prepare_server_key_exchange( mbedtls_ssl_context *ssl, | |
size_t *signature_len ) | |
{ | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED) | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
unsigned char *dig_signed = NULL; | |
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */ | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED */ | |
(void) ciphersuite_info; /* unused in some configurations */ | |
#if !defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
(void) signature_len; | |
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */ | |
ssl->out_msglen = 4; /* header (type:1, length:3) to be written later */ | |
/* | |
* | |
* Part 1: Provide key exchange parameters for chosen ciphersuite. | |
* | |
*/ | |
/* | |
* - ECJPAKE key exchanges | |
*/ | |
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE ) | |
{ | |
int ret; | |
size_t len = 0; | |
ret = mbedtls_ecjpake_write_round_two( | |
&ssl->handshake->ecjpake_ctx, | |
ssl->out_msg + ssl->out_msglen, | |
MBEDTLS_SSL_OUT_CONTENT_LEN - ssl->out_msglen, &len, | |
ssl->conf->f_rng, ssl->conf->p_rng ); | |
if( ret != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_write_round_two", ret ); | |
return( ret ); | |
} | |
ssl->out_msglen += len; | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ | |
/* | |
* For (EC)DHE key exchanges with PSK, parameters are prefixed by support | |
* identity hint (RFC 4279, Sec. 3). Until someone needs this feature, | |
* we use empty support identity hints here. | |
**/ | |
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) || \ | |
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK || | |
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ) | |
{ | |
ssl->out_msg[ssl->out_msglen++] = 0x00; | |
ssl->out_msg[ssl->out_msglen++] = 0x00; | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED || | |
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */ | |
/* | |
* - DHE key exchanges | |
*/ | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__DHE_ENABLED) | |
if( mbedtls_ssl_ciphersuite_uses_dhe( ciphersuite_info ) ) | |
{ | |
int ret; | |
size_t len = 0; | |
if( ssl->conf->dhm_P.p == NULL || ssl->conf->dhm_G.p == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no DH parameters set" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); | |
} | |
/* | |
* 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_set_group( &ssl->handshake->dhm_ctx, | |
&ssl->conf->dhm_P, | |
&ssl->conf->dhm_G ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_set_group", ret ); | |
return( ret ); | |
} | |
if( ( ret = mbedtls_dhm_make_params( | |
&ssl->handshake->dhm_ctx, | |
(int) mbedtls_mpi_size( &ssl->handshake->dhm_ctx.P ), | |
ssl->out_msg + ssl->out_msglen, &len, | |
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_make_params", ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
dig_signed = ssl->out_msg + ssl->out_msglen; | |
#endif | |
ssl->out_msglen += len; | |
MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: X ", &ssl->handshake->dhm_ctx.X ); | |
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: GX", &ssl->handshake->dhm_ctx.GX ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__DHE_ENABLED */ | |
/* | |
* - ECDHE key exchanges | |
*/ | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED) | |
if( mbedtls_ssl_ciphersuite_uses_ecdhe( ciphersuite_info ) ) | |
{ | |
/* | |
* Ephemeral ECDH parameters: | |
* | |
* struct { | |
* ECParameters curve_params; | |
* ECPoint public; | |
* } ServerECDHParams; | |
*/ | |
const mbedtls_ecp_curve_info **curve = NULL; | |
const mbedtls_ecp_group_id *gid; | |
int ret; | |
size_t len = 0; | |
/* Match our preference list against the offered curves */ | |
for( gid = ssl->conf->curve_list; *gid != MBEDTLS_ECP_DP_NONE; gid++ ) | |
for( curve = ssl->handshake->curves; *curve != NULL; curve++ ) | |
if( (*curve)->grp_id == *gid ) | |
goto curve_matching_done; | |
curve_matching_done: | |
if( curve == NULL || *curve == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "no matching curve for ECDHE" ) ); | |
return( MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "ECDHE curve: %s", (*curve)->name ) ); | |
if( ( ret = mbedtls_ecdh_setup( &ssl->handshake->ecdh_ctx, | |
(*curve)->grp_id ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecp_group_load", ret ); | |
return( ret ); | |
} | |
if( ( ret = mbedtls_ecdh_make_params( | |
&ssl->handshake->ecdh_ctx, &len, | |
ssl->out_msg + ssl->out_msglen, | |
MBEDTLS_SSL_OUT_CONTENT_LEN - ssl->out_msglen, | |
ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_make_params", ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
dig_signed = ssl->out_msg + ssl->out_msglen; | |
#endif | |
ssl->out_msglen += len; | |
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, | |
MBEDTLS_DEBUG_ECDH_Q ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED */ | |
/* | |
* | |
* Part 2: For key exchanges involving the server signing the | |
* exchange parameters, compute and add the signature here. | |
* | |
*/ | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
if( mbedtls_ssl_ciphersuite_uses_server_signature( ciphersuite_info ) ) | |
{ | |
size_t dig_signed_len = ssl->out_msg + ssl->out_msglen - dig_signed; | |
size_t hashlen = 0; | |
unsigned char hash[MBEDTLS_MD_MAX_SIZE]; | |
int ret; | |
/* | |
* 2.1: Choose hash algorithm: | |
* A: For TLS 1.2, obey signature-hash-algorithm extension | |
* to choose appropriate hash. | |
* B: For SSL3, TLS1.0, TLS1.1 and ECDHE_ECDSA, use SHA1 | |
* (RFC 4492, Sec. 5.4) | |
* C: Otherwise, use MD5 + SHA1 (RFC 4346, Sec. 7.4.3) | |
*/ | |
mbedtls_md_type_t md_alg; | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) | |
mbedtls_pk_type_t sig_alg = | |
mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info ); | |
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) | |
{ | |
/* A: For TLS 1.2, obey signature-hash-algorithm extension | |
* (RFC 5246, Sec. 7.4.1.4.1). */ | |
if( sig_alg == MBEDTLS_PK_NONE || | |
( md_alg = mbedtls_ssl_sig_hash_set_find( &ssl->handshake->hash_algs, | |
sig_alg ) ) == MBEDTLS_MD_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
/* (... because we choose a cipher suite | |
* only if there is a matching hash.) */ | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
} | |
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( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ) | |
{ | |
/* B: Default hash SHA1 */ | |
md_alg = MBEDTLS_MD_SHA1; | |
} | |
else | |
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \ | |
MBEDTLS_SSL_PROTO_TLS1_1 */ | |
{ | |
/* C: MD5 + SHA1 */ | |
md_alg = MBEDTLS_MD_NONE; | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "pick hash algorithm %d for signing", md_alg ) ); | |
/* | |
* 2.2: Compute the hash to be signed | |
*/ | |
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \ | |
defined(MBEDTLS_SSL_PROTO_TLS1_1) | |
if( md_alg == MBEDTLS_MD_NONE ) | |
{ | |
hashlen = 36; | |
ret = mbedtls_ssl_get_key_exchange_md_ssl_tls( ssl, hash, | |
dig_signed, | |
dig_signed_len ); | |
if( ret != 0 ) | |
return( ret ); | |
} | |
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 ) | |
{ | |
ret = mbedtls_ssl_get_key_exchange_md_tls1_2( ssl, hash, &hashlen, | |
dig_signed, | |
dig_signed_len, | |
md_alg ); | |
if( ret != 0 ) | |
return( ret ); | |
} | |
else | |
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \ | |
MBEDTLS_SSL_PROTO_TLS1_2 */ | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
MBEDTLS_SSL_DEBUG_BUF( 3, "parameters hash", hash, hashlen ); | |
/* | |
* 2.3: Compute and add the signature | |
*/ | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) | |
if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) | |
{ | |
/* | |
* For TLS 1.2, we need to specify signature and hash algorithm | |
* explicitly through a prefix to the signature. | |
* | |
* struct { | |
* HashAlgorithm hash; | |
* SignatureAlgorithm signature; | |
* } SignatureAndHashAlgorithm; | |
* | |
* struct { | |
* SignatureAndHashAlgorithm algorithm; | |
* opaque signature<0..2^16-1>; | |
* } DigitallySigned; | |
* | |
*/ | |
ssl->out_msg[ssl->out_msglen++] = | |
mbedtls_ssl_hash_from_md_alg( md_alg ); | |
ssl->out_msg[ssl->out_msglen++] = | |
mbedtls_ssl_sig_from_pk_alg( sig_alg ); | |
} | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
if( ssl->conf->f_async_sign_start != NULL ) | |
{ | |
ret = ssl->conf->f_async_sign_start( ssl, | |
mbedtls_ssl_own_cert( ssl ), | |
md_alg, hash, hashlen ); | |
switch( ret ) | |
{ | |
case MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH: | |
/* act as if f_async_sign was null */ | |
break; | |
case 0: | |
ssl->handshake->async_in_progress = 1; | |
return( ssl_resume_server_key_exchange( ssl, signature_len ) ); | |
case MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS: | |
ssl->handshake->async_in_progress = 1; | |
return( MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ); | |
default: | |
MBEDTLS_SSL_DEBUG_RET( 1, "f_async_sign_start", ret ); | |
return( ret ); | |
} | |
} | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
if( mbedtls_ssl_own_key( ssl ) == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no private key" ) ); | |
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED ); | |
} | |
/* Append the signature to ssl->out_msg, leaving 2 bytes for the | |
* signature length which will be added in ssl_write_server_key_exchange | |
* after the call to ssl_prepare_server_key_exchange. | |
* ssl_write_server_key_exchange also takes care of incrementing | |
* ssl->out_msglen. */ | |
if( ( ret = mbedtls_pk_sign( mbedtls_ssl_own_key( ssl ), | |
md_alg, hash, hashlen, | |
ssl->out_msg + ssl->out_msglen + 2, | |
signature_len, | |
ssl->conf->f_rng, | |
ssl->conf->p_rng ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_sign", ret ); | |
return( ret ); | |
} | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */ | |
return( 0 ); | |
} | |
/* Prepare the ServerKeyExchange message and send it. For ciphersuites | |
* that do not include a ServerKeyExchange message, do nothing. Either | |
* way, if successful, move on to the next step in the SSL state | |
* machine. */ | |
static int ssl_write_server_key_exchange( mbedtls_ssl_context *ssl ) | |
{ | |
int ret; | |
size_t signature_len = 0; | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED) | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED */ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write server key exchange" ) ); | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED) | |
/* Extract static ECDH parameters and abort if ServerKeyExchange | |
* is not needed. */ | |
if( mbedtls_ssl_ciphersuite_no_pfs( ciphersuite_info ) ) | |
{ | |
/* For suites involving ECDH, extract DH parameters | |
* from certificate at this point. */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED) | |
if( mbedtls_ssl_ciphersuite_uses_ecdh( ciphersuite_info ) ) | |
{ | |
ssl_get_ecdh_params_from_cert( ssl ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED */ | |
/* Key exchanges not involving ephemeral keys don't use | |
* ServerKeyExchange, so end here. */ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write server key exchange" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) && \ | |
defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
/* If we have already prepared the message and there is an ongoing | |
* signature operation, resume signing. */ | |
if( ssl->handshake->async_in_progress != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "resuming signature operation" ) ); | |
ret = ssl_resume_server_key_exchange( ssl, &signature_len ); | |
} | |
else | |
#endif /* defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) && | |
defined(MBEDTLS_SSL_ASYNC_PRIVATE) */ | |
{ | |
/* ServerKeyExchange is needed. Prepare the message. */ | |
ret = ssl_prepare_server_key_exchange( ssl, &signature_len ); | |
} | |
if( ret != 0 ) | |
{ | |
/* If we're starting to write a new message, set ssl->out_msglen | |
* to 0. But if we're resuming after an asynchronous message, | |
* out_msglen is the amount of data written so far and mst be | |
* preserved. */ | |
if( ret == MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ) | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write server key exchange (pending)" ) ); | |
else | |
ssl->out_msglen = 0; | |
return( ret ); | |
} | |
/* If there is a signature, write its length. | |
* ssl_prepare_server_key_exchange already wrote the signature | |
* itself at its proper place in the output buffer. */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED) | |
if( signature_len != 0 ) | |
{ | |
ssl->out_msg[ssl->out_msglen++] = (unsigned char)( signature_len >> 8 ); | |
ssl->out_msg[ssl->out_msglen++] = (unsigned char)( signature_len ); | |
MBEDTLS_SSL_DEBUG_BUF( 3, "my signature", | |
ssl->out_msg + ssl->out_msglen, | |
signature_len ); | |
/* Skip over the already-written signature */ | |
ssl->out_msglen += signature_len; | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */ | |
/* Add header and send. */ | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE; | |
ssl->state++; | |
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret ); | |
return( ret ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write server key exchange" ) ); | |
return( 0 ); | |
} | |
static int ssl_write_server_hello_done( mbedtls_ssl_context *ssl ) | |
{ | |
int ret; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write server hello done" ) ); | |
ssl->out_msglen = 4; | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_SERVER_HELLO_DONE; | |
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_handshake_msg( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && | |
( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flight_transmit", ret ); | |
return( ret ); | |
} | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write server hello done" ) ); | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \ | |
defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) | |
static int ssl_parse_client_dh_public( mbedtls_ssl_context *ssl, unsigned char **p, | |
const unsigned char *end ) | |
{ | |
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; | |
size_t n; | |
/* | |
* Receive G^Y mod P, premaster = (G^Y)^X mod P | |
*/ | |
if( *p + 2 > end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
n = ( (*p)[0] << 8 ) | (*p)[1]; | |
*p += 2; | |
if( *p + n > end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
if( ( ret = mbedtls_dhm_read_public( &ssl->handshake->dhm_ctx, *p, n ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_read_public", ret ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP ); | |
} | |
*p += n; | |
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_RSA_ENABLED) || \ | |
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
static int ssl_resume_decrypt_pms( mbedtls_ssl_context *ssl, | |
unsigned char *peer_pms, | |
size_t *peer_pmslen, | |
size_t peer_pmssize ) | |
{ | |
int ret = ssl->conf->f_async_resume( ssl, | |
peer_pms, peer_pmslen, peer_pmssize ); | |
if( ret != MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ) | |
{ | |
ssl->handshake->async_in_progress = 0; | |
mbedtls_ssl_set_async_operation_data( ssl, NULL ); | |
} | |
MBEDTLS_SSL_DEBUG_RET( 2, "ssl_decrypt_encrypted_pms", ret ); | |
return( ret ); | |
} | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
static int ssl_decrypt_encrypted_pms( mbedtls_ssl_context *ssl, | |
const unsigned char *p, | |
const unsigned char *end, | |
unsigned char *peer_pms, | |
size_t *peer_pmslen, | |
size_t peer_pmssize ) | |
{ | |
int ret; | |
mbedtls_pk_context *private_key = mbedtls_ssl_own_key( ssl ); | |
mbedtls_pk_context *public_key = &mbedtls_ssl_own_cert( ssl )->pk; | |
size_t len = mbedtls_pk_get_len( public_key ); | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
/* If we have already started decoding the message and there is an ongoing | |
* decryption operation, resume signing. */ | |
if( ssl->handshake->async_in_progress != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "resuming decryption operation" ) ); | |
return( ssl_resume_decrypt_pms( ssl, | |
peer_pms, peer_pmslen, peer_pmssize ) ); | |
} | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
/* | |
* Prepare to decrypt the premaster using own private RSA key | |
*/ | |
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \ | |
defined(MBEDTLS_SSL_PROTO_TLS1_2) | |
if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_0 ) | |
{ | |
if ( p + 2 > end ) { | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
if( *p++ != ( ( len >> 8 ) & 0xFF ) || | |
*p++ != ( ( len ) & 0xFF ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
} | |
#endif | |
if( p + len != end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
/* | |
* Decrypt the premaster secret | |
*/ | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
if( ssl->conf->f_async_decrypt_start != NULL ) | |
{ | |
ret = ssl->conf->f_async_decrypt_start( ssl, | |
mbedtls_ssl_own_cert( ssl ), | |
p, len ); | |
switch( ret ) | |
{ | |
case MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH: | |
/* act as if f_async_decrypt_start was null */ | |
break; | |
case 0: | |
ssl->handshake->async_in_progress = 1; | |
return( ssl_resume_decrypt_pms( ssl, | |
peer_pms, | |
peer_pmslen, | |
peer_pmssize ) ); | |
case MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS: | |
ssl->handshake->async_in_progress = 1; | |
return( MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ); | |
default: | |
MBEDTLS_SSL_DEBUG_RET( 1, "f_async_decrypt_start", ret ); | |
return( ret ); | |
} | |
} | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
if( ! mbedtls_pk_can_do( private_key, MBEDTLS_PK_RSA ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no RSA private key" ) ); | |
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED ); | |
} | |
ret = mbedtls_pk_decrypt( private_key, p, len, | |
peer_pms, peer_pmslen, peer_pmssize, | |
ssl->conf->f_rng, ssl->conf->p_rng ); | |
return( ret ); | |
} | |
static int ssl_parse_encrypted_pms( mbedtls_ssl_context *ssl, | |
const unsigned char *p, | |
const unsigned char *end, | |
size_t pms_offset ) | |
{ | |
int ret; | |
unsigned char *pms = ssl->handshake->premaster + pms_offset; | |
unsigned char ver[2]; | |
unsigned char fake_pms[48], peer_pms[48]; | |
unsigned char mask; | |
size_t i, peer_pmslen; | |
unsigned int diff; | |
/* In case of a failure in decryption, the decryption may write less than | |
* 2 bytes of output, but we always read the first two bytes. It doesn't | |
* matter in the end because diff will be nonzero in that case due to | |
* peer_pmslen being less than 48, and we only care whether diff is 0. | |
* But do initialize peer_pms for robustness anyway. This also makes | |
* memory analyzers happy (don't access uninitialized memory, even | |
* if it's an unsigned char). */ | |
peer_pms[0] = peer_pms[1] = ~0; | |
ret = ssl_decrypt_encrypted_pms( ssl, p, end, | |
peer_pms, | |
&peer_pmslen, | |
sizeof( peer_pms ) ); | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
if ( ret == MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS ) | |
return( ret ); | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
mbedtls_ssl_write_version( ssl->handshake->max_major_ver, | |
ssl->handshake->max_minor_ver, | |
ssl->conf->transport, ver ); | |
/* Avoid data-dependent branches while checking for invalid | |
* padding, to protect against timing-based Bleichenbacher-type | |
* attacks. */ | |
diff = (unsigned int) ret; | |
diff |= peer_pmslen ^ 48; | |
diff |= peer_pms[0] ^ ver[0]; | |
diff |= peer_pms[1] ^ ver[1]; | |
/* mask = diff ? 0xff : 0x00 using bit operations to avoid branches */ | |
/* MSVC has a warning about unary minus on unsigned, but this is | |
* well-defined and precisely what we want to do here */ | |
#if defined(_MSC_VER) | |
#pragma warning( push ) | |
#pragma warning( disable : 4146 ) | |
#endif | |
mask = - ( ( diff | - diff ) >> ( sizeof( unsigned int ) * 8 - 1 ) ); | |
#if defined(_MSC_VER) | |
#pragma warning( pop ) | |
#endif | |
/* | |
* Protection against Bleichenbacher's attack: invalid PKCS#1 v1.5 padding | |
* must not cause the connection to end immediately; instead, send a | |
* bad_record_mac later in the handshake. | |
* To protect against timing-based variants of the attack, we must | |
* not have any branch that depends on whether the decryption was | |
* successful. In particular, always generate the fake premaster secret, | |
* regardless of whether it will ultimately influence the output or not. | |
*/ | |
ret = ssl->conf->f_rng( ssl->conf->p_rng, fake_pms, sizeof( fake_pms ) ); | |
if( ret != 0 ) | |
{ | |
/* It's ok to abort on an RNG failure, since this does not reveal | |
* anything about the RSA decryption. */ | |
return( ret ); | |
} | |
#if defined(MBEDTLS_SSL_DEBUG_ALL) | |
if( diff != 0 ) | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
#endif | |
if( sizeof( ssl->handshake->premaster ) < pms_offset || | |
sizeof( ssl->handshake->premaster ) - pms_offset < 48 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
ssl->handshake->pmslen = 48; | |
/* Set pms to either the true or the fake PMS, without | |
* data-dependent branches. */ | |
for( i = 0; i < ssl->handshake->pmslen; i++ ) | |
pms[i] = ( mask & fake_pms[i] ) | ( (~mask) & peer_pms[i] ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED || | |
MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) | |
static int ssl_parse_client_psk_identity( mbedtls_ssl_context *ssl, unsigned char **p, | |
const unsigned char *end ) | |
{ | |
int ret = 0; | |
size_t n; | |
if( ssl_conf_has_psk_or_cb( ssl->conf ) == 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no pre-shared key" ) ); | |
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED ); | |
} | |
/* | |
* Receive client pre-shared key identity name | |
*/ | |
if( end - *p < 2 ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
n = ( (*p)[0] << 8 ) | (*p)[1]; | |
*p += 2; | |
if( n < 1 || n > 65535 || n > (size_t) ( end - *p ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
if( ssl->conf->f_psk != NULL ) | |
{ | |
if( ssl->conf->f_psk( ssl->conf->p_psk, ssl, *p, n ) != 0 ) | |
ret = MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY; | |
} | |
else | |
{ | |
/* Identity is not a big secret since clients send it in the clear, | |
* but treat it carefully anyway, just in case */ | |
if( n != ssl->conf->psk_identity_len || | |
mbedtls_ssl_safer_memcmp( ssl->conf->psk_identity, *p, n ) != 0 ) | |
{ | |
ret = MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY; | |
} | |
} | |
if( ret == MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY ) | |
{ | |
MBEDTLS_SSL_DEBUG_BUF( 3, "Unknown PSK identity", *p, n ); | |
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, | |
MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY ); | |
return( MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY ); | |
} | |
*p += n; | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */ | |
static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl ) | |
{ | |
int ret; | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info; | |
unsigned char *p, *end; | |
ciphersuite_info = ssl->handshake->ciphersuite_info; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse client key exchange" ) ); | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) && \ | |
( defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) || \ | |
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) ) | |
if( ( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK || | |
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA ) && | |
( ssl->handshake->async_in_progress != 0 ) ) | |
{ | |
/* We've already read a record and there is an asynchronous | |
* operation in progress to decrypt it. So skip reading the | |
* record. */ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "will resume decryption of previously-read record" ) ); | |
} | |
else | |
#endif | |
if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); | |
return( ret ); | |
} | |
p = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ); | |
end = ssl->in_msg + ssl->in_hslen; | |
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
if( ssl->in_msg[0] != MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA ) | |
{ | |
if( ( ret = ssl_parse_client_dh_public( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_dh_public" ), ret ); | |
return( ret ); | |
} | |
if( p != end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
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( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS ); | |
} | |
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 ) | |
{ | |
if( ( ret = mbedtls_ecdh_read_public( &ssl->handshake->ecdh_ctx, | |
p, end - p) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_read_public", ret ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP ); | |
} | |
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, | |
MBEDTLS_DEBUG_ECDH_QP ); | |
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( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS ); | |
} | |
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, | |
MBEDTLS_DEBUG_ECDH_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_PSK_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ) | |
{ | |
if( ( ret = ssl_parse_client_psk_identity( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret ); | |
return( ret ); | |
} | |
if( p != end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
/* For opaque PSKs, we perform the PSK-to-MS derivation atomatically | |
* and skip the intermediate PMS. */ | |
if( ssl_use_opaque_psk( ssl ) == 1 ) | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "skip PMS generation for opaque PSK" ) ); | |
else | |
#endif /* MBEDTLS_USE_PSA_CRYPTO */ | |
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_PSK_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ) | |
{ | |
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | |
if ( ssl->handshake->async_in_progress != 0 ) | |
{ | |
/* There is an asynchronous operation in progress to | |
* decrypt the encrypted premaster secret, so skip | |
* directly to resuming this operation. */ | |
MBEDTLS_SSL_DEBUG_MSG( 3, ( "PSK identity already parsed" ) ); | |
/* Update p to skip the PSK identity. ssl_parse_encrypted_pms | |
* won't actually use it, but maintain p anyway for robustness. */ | |
p += ssl->conf->psk_identity_len + 2; | |
} | |
else | |
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | |
if( ( ret = ssl_parse_client_psk_identity( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
/* Opaque PSKs are currently only supported for PSK-only. */ | |
if( ssl_use_opaque_psk( ssl ) == 1 ) | |
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); | |
#endif | |
if( ( ret = ssl_parse_encrypted_pms( ssl, p, end, 2 ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_encrypted_pms" ), ret ); | |
return( ret ); | |
} | |
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_RSA_PSK_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ) | |
{ | |
if( ( ret = ssl_parse_client_psk_identity( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret ); | |
return( ret ); | |
} | |
if( ( ret = ssl_parse_client_dh_public( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_dh_public" ), ret ); | |
return( ret ); | |
} | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
/* Opaque PSKs are currently only supported for PSK-only. */ | |
if( ssl_use_opaque_psk( ssl ) == 1 ) | |
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); | |
#endif | |
if( p != end ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE ); | |
} | |
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_DHE_PSK_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ) | |
{ | |
if( ( ret = ssl_parse_client_psk_identity( ssl, &p, end ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret ); | |
return( ret ); | |
} | |
if( ( ret = mbedtls_ecdh_read_public( &ssl->handshake->ecdh_ctx, | |
p, end - p ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_read_public", ret ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP ); | |
} | |
#if defined(MBEDTLS_USE_PSA_CRYPTO) | |
/* Opaque PSKs are currently only supported for PSK-only. */ | |
if( ssl_use_opaque_psk( ssl ) == 1 ) | |
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); | |
#endif | |
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, | |
MBEDTLS_DEBUG_ECDH_QP ); | |
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_ECDHE_PSK_ENABLED */ | |
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) | |
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA ) | |
{ | |
if( ( ret = ssl_parse_encrypted_pms( ssl, p, end, 0 ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_parse_encrypted_pms_secret" ), ret ); | |
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 ) | |
{ | |
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 ); | |
} | |
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_ECJPAKE_ENABLED */ | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret ); | |
return( ret ); | |
} | |
ssl->state++; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse client key exchange" ) ); | |
return( 0 ); | |
} | |
#if !defined(MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED) | |
static int ssl_parse_certificate_verify( mbedtls_ssl_context *ssl ) | |
{ | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate verify" ) ); | |
if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate verify" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
#else /* !MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED */ | |
static int ssl_parse_certificate_verify( mbedtls_ssl_context *ssl ) | |
{ | |
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; | |
size_t i, sig_len; | |
unsigned char hash[48]; | |
unsigned char *hash_start = hash; | |
size_t hashlen; | |
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) | |
mbedtls_pk_type_t pk_alg; | |
#endif | |
mbedtls_md_type_t md_alg; | |
const mbedtls_ssl_ciphersuite_t *ciphersuite_info = | |
ssl->handshake->ciphersuite_info; | |
mbedtls_pk_context * peer_pk; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate verify" ) ); | |
if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate verify" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) | |
if( ssl->session_negotiate->peer_cert == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate verify" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | |
if( ssl->session_negotiate->peer_cert_digest == NULL ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate verify" ) ); | |
ssl->state++; | |
return( 0 ); | |
} | |
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | |
/* Read the message without adding it to the checksum */ | |
ret = mbedtls_ssl_read_record( ssl, 0 /* no checksum update */ ); | |
if( 0 != ret ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ssl_read_record" ), ret ); | |
return( ret ); | |
} | |
ssl->state++; | |
/* Process the message contents */ | |
if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE || | |
ssl->in_msg[0] != MBEDTLS_SSL_HS_CERTIFICATE_VERIFY ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
i = mbedtls_ssl_hs_hdr_len( ssl ); | |
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) | |
peer_pk = &ssl->handshake->peer_pubkey; | |
#else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | |
if( ssl->session_negotiate->peer_cert == NULL ) | |
{ | |
/* Should never happen */ | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
peer_pk = &ssl->session_negotiate->peer_cert->pk; | |
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | |
/* | |
* struct { | |
* SignatureAndHashAlgorithm algorithm; -- TLS 1.2 only | |
* opaque signature<0..2^16-1>; | |
* } DigitallySigned; | |
*/ | |
#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 ) | |
{ | |
md_alg = MBEDTLS_MD_NONE; | |
hashlen = 36; | |
/* For ECDSA, use SHA-1, not MD-5 + SHA-1 */ | |
if( mbedtls_pk_can_do( peer_pk, 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 ) | |
{ | |
if( i + 2 > ssl->in_hslen ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
/* | |
* Hash | |
*/ | |
md_alg = mbedtls_ssl_md_alg_from_hash( ssl->in_msg[i] ); | |
if( md_alg == MBEDTLS_MD_NONE || mbedtls_ssl_set_calc_verify_md( ssl, ssl->in_msg[i] ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "peer not adhering to requested sig_alg" | |
" for verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
#if !defined(MBEDTLS_MD_SHA1) | |
if( MBEDTLS_MD_SHA1 == md_alg ) | |
hash_start += 16; | |
#endif | |
/* Info from md_alg will be used instead */ | |
hashlen = 0; | |
i++; | |
/* | |
* Signature | |
*/ | |
if( ( pk_alg = mbedtls_ssl_pk_alg_from_sig( ssl->in_msg[i] ) ) | |
== MBEDTLS_PK_NONE ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "peer not adhering to requested sig_alg" | |
" for verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
/* | |
* Check the certificate's key type matches the signature alg | |
*/ | |
if( !mbedtls_pk_can_do( peer_pk, pk_alg ) ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "sig_alg doesn't match cert key" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
i++; | |
} | |
else | |
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); | |
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); | |
} | |
if( i + 2 > ssl->in_hslen ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
sig_len = ( ssl->in_msg[i] << 8 ) | ssl->in_msg[i+1]; | |
i += 2; | |
if( i + sig_len != ssl->in_hslen ) | |
{ | |
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate verify message" ) ); | |
return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY ); | |
} | |
/* Calculate hash and verify signature */ | |
ssl->handshake->calc_verify( ssl, hash ); | |
if( ( ret = mbedtls_pk_verify( peer_pk, | |
md_alg, hash_start, hashlen, | |
ssl->in_msg + i, sig_len ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_verify", ret ); | |
return( ret ); | |
} | |
mbedtls_ssl_update_handshake_status( ssl ); | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate verify" ) ); | |
return( ret ); | |
} | |
#endif /* MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED */ | |
#if defined(MBEDTLS_SSL_SESSION_TICKETS) | |
static int ssl_write_new_session_ticket( mbedtls_ssl_context *ssl ) | |
{ | |
int ret; | |
size_t tlen; | |
uint32_t lifetime; | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write new session ticket" ) ); | |
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; | |
ssl->out_msg[0] = MBEDTLS_SSL_HS_NEW_SESSION_TICKET; | |
/* | |
* struct { | |
* uint32 ticket_lifetime_hint; | |
* opaque ticket<0..2^16-1>; | |
* } NewSessionTicket; | |
* | |
* 4 . 7 ticket_lifetime_hint (0 = unspecified) | |
* 8 . 9 ticket_len (n) | |
* 10 . 9+n ticket content | |
*/ | |
if( ( ret = ssl->conf->f_ticket_write( ssl->conf->p_ticket, | |
ssl->session_negotiate, | |
ssl->out_msg + 10, | |
ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN, | |
&tlen, &lifetime ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_ticket_write", ret ); | |
tlen = 0; | |
} | |
ssl->out_msg[4] = ( lifetime >> 24 ) & 0xFF; | |
ssl->out_msg[5] = ( lifetime >> 16 ) & 0xFF; | |
ssl->out_msg[6] = ( lifetime >> 8 ) & 0xFF; | |
ssl->out_msg[7] = ( lifetime ) & 0xFF; | |
ssl->out_msg[8] = (unsigned char)( ( tlen >> 8 ) & 0xFF ); | |
ssl->out_msg[9] = (unsigned char)( ( tlen ) & 0xFF ); | |
ssl->out_msglen = 10 + tlen; | |
/* | |
* Morally equivalent to updating ssl->state, but NewSessionTicket and | |
* ChangeCipherSpec share the same state. | |
*/ | |
ssl->handshake->new_session_ticket = 0; | |
if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 ) | |
{ | |
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret ); | |
return( ret ); | |
} | |
MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write new session ticket" ) ); | |
return( 0 ); | |
} | |
#endif /* MBEDTLS_SSL_SESSION_TICKETS */ | |
/* | |
* SSL handshake -- server side -- single step | |
*/ | |
int mbedtls_ssl_handshake_server_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, ( "server 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_flight_transmit( ssl ) ) != 0 ) | |
return( ret ); | |
} | |
#endif /* MBEDTLS_SSL_PROTO_DTLS */ | |
switch( ssl->state ) | |
{ | |
case MBEDTLS_SSL_HELLO_REQUEST: | |
ssl->state = MBEDTLS_SSL_CLIENT_HELLO; | |
break; | |
/* | |
* <== ClientHello | |
*/ | |
case MBEDTLS_SSL_CLIENT_HELLO: | |
ret = ssl_parse_client_hello( ssl ); | |
break; | |
#if defined(MBEDTLS_SSL_PROTO_DTLS) | |
case MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT: | |
return( MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED ); | |
#endif | |
/* | |
* ==> ServerHello | |
* Certificate | |
* ( ServerKeyExchange ) | |
* ( CertificateRequest ) | |
* ServerHelloDone | |
*/ | |
case MBEDTLS_SSL_SERVER_HELLO: | |
ret = ssl_write_server_hello( ssl ); | |
break; | |
case MBEDTLS_SSL_SERVER_CERTIFICATE: | |
ret = mbedtls_ssl_write_certificate( ssl ); | |
break; | |
case MBEDTLS_SSL_SERVER_KEY_EXCHANGE: | |
ret = ssl_write_server_key_exchange( ssl ); | |
break; | |
case MBEDTLS_SSL_CERTIFICATE_REQUEST: | |
ret = ssl_write_certificate_request( ssl ); | |
break; | |
case MBEDTLS_SSL_SERVER_HELLO_DONE: | |
ret = ssl_write_server_hello_done( ssl ); | |
break; | |
/* | |
* <== ( Certificate/Alert ) | |
* ClientKeyExchange | |
* ( CertificateVerify ) | |
* ChangeCipherSpec | |
* Finished | |
*/ | |
case MBEDTLS_SSL_CLIENT_CERTIFICATE: | |
ret = mbedtls_ssl_parse_certificate( ssl ); | |
break; | |
case MBEDTLS_SSL_CLIENT_KEY_EXCHANGE: | |
ret = ssl_parse_client_key_exchange( ssl ); | |
break; | |
case MBEDTLS_SSL_CERTIFICATE_VERIFY: | |
ret = ssl_parse_certificate_verify( ssl ); | |
break; | |
case MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC: | |
ret = mbedtls_ssl_parse_change_cipher_spec( ssl ); | |
break; | |
case MBEDTLS_SSL_CLIENT_FINISHED: | |
ret = mbedtls_ssl_parse_finished( ssl ); | |
break; | |
/* | |
* ==> ( NewSessionTicket ) | |
* ChangeCipherSpec | |
* Finished | |
*/ | |
case MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC: | |
#if defined(MBEDTLS_SSL_SESSION_TICKETS) | |
if( ssl->handshake->new_session_ticket != 0 ) | |
ret = ssl_write_new_session_ticket( ssl ); | |
else | |
#endif | |
ret = mbedtls_ssl_write_change_cipher_spec( ssl ); | |
break; | |
case MBEDTLS_SSL_SERVER_FINISHED: | |
ret = mbedtls_ssl_write_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_SRV_C */ |