diff options
Diffstat (limited to 'lib/mbedtls-2.27.0/library/ssl_cli.c')
| -rw-r--r-- | lib/mbedtls-2.27.0/library/ssl_cli.c | 4545 |
1 files changed, 4545 insertions, 0 deletions
diff --git a/lib/mbedtls-2.27.0/library/ssl_cli.c b/lib/mbedtls-2.27.0/library/ssl_cli.c new file mode 100644 index 0000000..f49178c --- /dev/null +++ b/lib/mbedtls-2.27.0/library/ssl_cli.c @@ -0,0 +1,4545 @@ +/* + * SSLv3/TLSv1 client-side functions + * + * Copyright The Mbed TLS Contributors + * 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. + */ + +#include "common.h" + +#if defined(MBEDTLS_SSL_CLI_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/ssl.h" +#include "mbedtls/ssl_internal.h" +#include "mbedtls/debug.h" +#include "mbedtls/error.h" + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +#include "mbedtls/psa_util.h" +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + +#include <string.h> + +#include <stdint.h> + +#if defined(MBEDTLS_HAVE_TIME) +#include "mbedtls/platform_time.h" +#endif + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) +#include "mbedtls/platform_util.h" +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) +static int ssl_conf_has_static_psk( mbedtls_ssl_config const *conf ) +{ + if( conf->psk_identity == NULL || + conf->psk_identity_len == 0 ) + { + return( 0 ); + } + + if( conf->psk != NULL && conf->psk_len != 0 ) + return( 1 ); + +#if defined(MBEDTLS_USE_PSA_CRYPTO) + if( ! mbedtls_svc_key_id_is_null( conf->psk_opaque ) ) + return( 1 ); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + return( 0 ); +} + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +static int ssl_conf_has_static_raw_psk( mbedtls_ssl_config const *conf ) +{ + if( conf->psk_identity == NULL || + conf->psk_identity_len == 0 ) + { + return( 0 ); + } + + if( conf->psk != NULL && conf->psk_len != 0 ) + return( 1 ); + + return( 0 ); +} +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ + +#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) +static int ssl_write_hostname_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t hostname_len; + + *olen = 0; + + if( ssl->hostname == NULL ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding server name extension: %s", + ssl->hostname ) ); + + hostname_len = strlen( ssl->hostname ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, hostname_len + 9 ); + + /* + * Sect. 3, RFC 6066 (TLS Extensions Definitions) + * + * In order to provide any of the server names, clients MAY include an + * extension of type "server_name" in the (extended) client hello. The + * "extension_data" field of this extension SHALL contain + * "ServerNameList" where: + * + * struct { + * NameType name_type; + * select (name_type) { + * case host_name: HostName; + * } name; + * } ServerName; + * + * enum { + * host_name(0), (255) + * } NameType; + * + * opaque HostName<1..2^16-1>; + * + * struct { + * ServerName server_name_list<1..2^16-1> + * } ServerNameList; + * + */ + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME ) & 0xFF ); + + *p++ = (unsigned char)( ( (hostname_len + 5) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( (hostname_len + 5) ) & 0xFF ); + + *p++ = (unsigned char)( ( (hostname_len + 3) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( (hostname_len + 3) ) & 0xFF ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME ) & 0xFF ); + *p++ = (unsigned char)( ( hostname_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( hostname_len ) & 0xFF ); + + memcpy( p, ssl->hostname, hostname_len ); + + *olen = hostname_len + 9; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ + +#if defined(MBEDTLS_SSL_RENEGOTIATION) +static int ssl_write_renegotiation_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + /* We're always including an TLS_EMPTY_RENEGOTIATION_INFO_SCSV in the + * initial ClientHello, in which case also adding the renegotiation + * info extension is NOT RECOMMENDED as per RFC 5746 Section 3.4. */ + if( ssl->renego_status != MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding renegotiation extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 5 + ssl->verify_data_len ); + + /* + * Secure renegotiation + */ + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO >> 8 ) + & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_RENEGOTIATION_INFO ) + & 0xFF ); + + *p++ = 0x00; + *p++ = ( ssl->verify_data_len + 1 ) & 0xFF; + *p++ = ssl->verify_data_len & 0xFF; + + memcpy( p, ssl->own_verify_data, ssl->verify_data_len ); + + *olen = 5 + ssl->verify_data_len; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_RENEGOTIATION */ + +/* + * Only if we handle at least one key exchange that needs signatures. + */ +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ + defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) +static int ssl_write_signature_algorithms_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t sig_alg_len = 0; + const int *md; + +#if defined(MBEDTLS_RSA_C) || defined(MBEDTLS_ECDSA_C) + unsigned char *sig_alg_list = buf + 6; +#endif + + *olen = 0; + + if( ssl->conf->max_minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding signature_algorithms extension" ) ); + + if( ssl->conf->sig_hashes == NULL ) + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + + for( md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++ ) + { +#if defined(MBEDTLS_ECDSA_C) + sig_alg_len += 2; +#endif +#if defined(MBEDTLS_RSA_C) + sig_alg_len += 2; +#endif + if( sig_alg_len > MBEDTLS_SSL_MAX_SIG_HASH_ALG_LIST_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "length in bytes of sig-hash-alg extension too big" ) ); + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + } + } + + /* Empty signature algorithms list, this is a configuration error. */ + if( sig_alg_len == 0 ) + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, sig_alg_len + 6 ); + + /* + * Prepare signature_algorithms extension (TLS 1.2) + */ + sig_alg_len = 0; + + for( md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++ ) + { +#if defined(MBEDTLS_ECDSA_C) + sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg( *md ); + sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_ECDSA; +#endif +#if defined(MBEDTLS_RSA_C) + sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg( *md ); + sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_RSA; +#endif + } + + /* + * enum { + * none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5), + * sha512(6), (255) + * } HashAlgorithm; + * + * enum { anonymous(0), rsa(1), dsa(2), ecdsa(3), (255) } + * SignatureAlgorithm; + * + * struct { + * HashAlgorithm hash; + * SignatureAlgorithm signature; + * } SignatureAndHashAlgorithm; + * + * SignatureAndHashAlgorithm + * supported_signature_algorithms<2..2^16-2>; + */ + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SIG_ALG >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SIG_ALG ) & 0xFF ); + + *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) ) & 0xFF ); + + *p++ = (unsigned char)( ( sig_alg_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( sig_alg_len ) & 0xFF ); + + *olen = 6 + sig_alg_len; + + 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_write_supported_elliptic_curves_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + unsigned char *elliptic_curve_list = p + 6; + size_t elliptic_curve_len = 0; + const mbedtls_ecp_curve_info *info; + const mbedtls_ecp_group_id *grp_id; + + *olen = 0; + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding supported_elliptic_curves extension" ) ); + + if( ssl->conf->curve_list == NULL ) + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + + for( grp_id = ssl->conf->curve_list; + *grp_id != MBEDTLS_ECP_DP_NONE; + grp_id++ ) + { + info = mbedtls_ecp_curve_info_from_grp_id( *grp_id ); + if( info == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "invalid curve in ssl configuration" ) ); + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + } + elliptic_curve_len += 2; + + if( elliptic_curve_len > MBEDTLS_SSL_MAX_CURVE_LIST_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "malformed supported_elliptic_curves extension in config" ) ); + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + } + } + + /* Empty elliptic curve list, this is a configuration error. */ + if( elliptic_curve_len == 0 ) + return( MBEDTLS_ERR_SSL_BAD_CONFIG ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 + elliptic_curve_len ); + + elliptic_curve_len = 0; + + for( grp_id = ssl->conf->curve_list; + *grp_id != MBEDTLS_ECP_DP_NONE; + grp_id++ ) + { + info = mbedtls_ecp_curve_info_from_grp_id( *grp_id ); + elliptic_curve_list[elliptic_curve_len++] = info->tls_id >> 8; + elliptic_curve_list[elliptic_curve_len++] = info->tls_id & 0xFF; + } + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES >> 8 ) + & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES ) + & 0xFF ); + + *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) ) & 0xFF ); + + *p++ = (unsigned char)( ( ( elliptic_curve_len ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( elliptic_curve_len ) ) & 0xFF ); + + *olen = 6 + elliptic_curve_len; + + return( 0 ); +} + +static int ssl_write_supported_point_formats_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + (void) ssl; /* ssl used for debugging only */ + + *olen = 0; + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding supported_point_formats extension" ) ); + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 ); + + *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; + + return( 0 ); +} +#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || + MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) +static int ssl_write_ecjpake_kkpp_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + unsigned char *p = buf; + size_t kkpp_len; + + *olen = 0; + + /* Skip costly extension if we can't use EC J-PAKE anyway */ + if( mbedtls_ecjpake_check( &ssl->handshake->ecjpake_ctx ) != 0 ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding ecjpake_kkpp extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ECJPAKE_KKPP >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ECJPAKE_KKPP ) & 0xFF ); + + /* + * We may need to send ClientHello multiple times for Hello verification. + * We don't want to compute fresh values every time (both for performance + * and consistency reasons), so cache the extension content. + */ + if( ssl->handshake->ecjpake_cache == NULL || + ssl->handshake->ecjpake_cache_len == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "generating new ecjpake parameters" ) ); + + ret = mbedtls_ecjpake_write_round_one( &ssl->handshake->ecjpake_ctx, + p + 2, end - p - 2, &kkpp_len, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1 , + "mbedtls_ecjpake_write_round_one", ret ); + return( ret ); + } + + ssl->handshake->ecjpake_cache = mbedtls_calloc( 1, kkpp_len ); + if( ssl->handshake->ecjpake_cache == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "allocation failed" ) ); + return( MBEDTLS_ERR_SSL_ALLOC_FAILED ); + } + + memcpy( ssl->handshake->ecjpake_cache, p + 2, kkpp_len ); + ssl->handshake->ecjpake_cache_len = kkpp_len; + } + else + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "re-using cached ecjpake parameters" ) ); + + kkpp_len = ssl->handshake->ecjpake_cache_len; + MBEDTLS_SSL_CHK_BUF_PTR( p + 2, end, kkpp_len ); + + memcpy( p + 2, ssl->handshake->ecjpake_cache, kkpp_len ); + } + + *p++ = (unsigned char)( ( kkpp_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( kkpp_len ) & 0xFF ); + + *olen = kkpp_len + 4; + + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) +static int ssl_write_cid_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t ext_len; + + /* + * 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; + */ + + *olen = 0; + if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM || + ssl->negotiate_cid == MBEDTLS_SSL_CID_DISABLED ) + { + return( 0 ); + } + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding CID extension" ) ); + + /* ssl->own_cid_len is at most MBEDTLS_SSL_CID_IN_LEN_MAX + * which is at most 255, so the increment cannot overflow. */ + MBEDTLS_SSL_CHK_BUF_PTR( p, end, (unsigned)( ssl->own_cid_len + 5 ) ); + + /* Add extension ID + size */ + *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; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ + +#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) +static int ssl_write_max_fragment_length_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if( ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding max_fragment_length extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 5 ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH >> 8 ) + & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH ) + & 0xFF ); + + *p++ = 0x00; + *p++ = 1; + + *p++ = ssl->conf->mfl_code; + + *olen = 5; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ + +#if defined(MBEDTLS_SSL_TRUNCATED_HMAC) +static int ssl_write_truncated_hmac_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding truncated_hmac extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 ); + + *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; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ + +#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) +static int ssl_write_encrypt_then_mac_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if( ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED || + ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding encrypt_then_mac extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 ); + + *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; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ + +#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) +static int ssl_write_extended_ms_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if( ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED || + ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding extended_master_secret extension" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 ); + + *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; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) +static int ssl_write_session_ticket_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t tlen = ssl->session_negotiate->ticket_len; + + *olen = 0; + + if( ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, adding session ticket extension" ) ); + + /* The addition is safe here since the ticket length is 16 bit. */ + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 + tlen ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_SESSION_TICKET ) & 0xFF ); + + *p++ = (unsigned char)( ( tlen >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( tlen ) & 0xFF ); + + *olen = 4; + + if( ssl->session_negotiate->ticket == NULL || tlen == 0 ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "sending session ticket of length %" MBEDTLS_PRINTF_SIZET, tlen ) ); + + memcpy( p, ssl->session_negotiate->ticket, tlen ); + + *olen += tlen; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + +#if defined(MBEDTLS_SSL_ALPN) +static int ssl_write_alpn_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t alpnlen = 0; + const char **cur; + + *olen = 0; + + if( ssl->conf->alpn_list == NULL ) + return( 0 ); + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding alpn extension" ) ); + + for( cur = ssl->conf->alpn_list; *cur != NULL; cur++ ) + alpnlen += strlen( *cur ) + 1; + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 + alpnlen ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_ALPN ) & 0xFF ); + + /* + * opaque ProtocolName<1..2^8-1>; + * + * struct { + * ProtocolName protocol_name_list<2..2^16-1> + * } ProtocolNameList; + */ + + /* Skip writing extension and list length for now */ + p += 4; + + for( cur = ssl->conf->alpn_list; *cur != NULL; cur++ ) + { + /* + * mbedtls_ssl_conf_set_alpn_protocols() checked that the length of + * protocol names is less than 255. + */ + *p = (unsigned char)strlen( *cur ); + memcpy( p + 1, *cur, *p ); + p += 1 + *p; + } + + *olen = p - buf; + + /* List length = olen - 2 (ext_type) - 2 (ext_len) - 2 (list_len) */ + buf[4] = (unsigned char)( ( ( *olen - 6 ) >> 8 ) & 0xFF ); + buf[5] = (unsigned char)( ( ( *olen - 6 ) ) & 0xFF ); + + /* Extension length = olen - 2 (ext_type) - 2 (ext_len) */ + buf[2] = (unsigned char)( ( ( *olen - 4 ) >> 8 ) & 0xFF ); + buf[3] = (unsigned char)( ( ( *olen - 4 ) ) & 0xFF ); + + return( 0 ); +} +#endif /* MBEDTLS_SSL_ALPN */ + +#if defined(MBEDTLS_SSL_DTLS_SRTP) +static int ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + size_t *olen ) +{ + unsigned char *p = buf; + size_t protection_profiles_index = 0, ext_len = 0; + uint16_t mki_len = 0, profile_value = 0; + + *olen = 0; + + if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) || + ( ssl->conf->dtls_srtp_profile_list == NULL ) || + ( ssl->conf->dtls_srtp_profile_list_len == 0 ) ) + { + return( 0 ); + } + + /* RFC 5764 section 4.1.1 + * uint8 SRTPProtectionProfile[2]; + * + * struct { + * SRTPProtectionProfiles SRTPProtectionProfiles; + * opaque srtp_mki<0..255>; + * } UseSRTPData; + * SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>; + */ + if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED ) + { + mki_len = ssl->dtls_srtp_info.mki_len; + } + /* Extension length = 2 bytes for profiles length, + * ssl->conf->dtls_srtp_profile_list_len * 2 (each profile is 2 bytes length ), + * 1 byte for srtp_mki vector length and the mki_len value + */ + ext_len = 2 + 2 * ( ssl->conf->dtls_srtp_profile_list_len ) + 1 + mki_len; + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding use_srtp extension" ) ); + + /* Check there is room in the buffer for the extension + 4 bytes + * - the extension tag (2 bytes) + * - the extension length (2 bytes) + */ + MBEDTLS_SSL_CHK_BUF_PTR( p, end, ext_len + 4 ); + + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP ) & 0xFF ); + + + *p++ = (unsigned char)( ( ( ext_len & 0xFF00 ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ext_len & 0xFF ); + + /* protection profile length: 2*(ssl->conf->dtls_srtp_profile_list_len) */ + /* micro-optimization: + * the list size is limited to MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH + * which is lower than 127, so the upper byte of the length is always 0 + * For the documentation, the more generic code is left in comments + * *p++ = (unsigned char)( ( ( 2 * ssl->conf->dtls_srtp_profile_list_len ) + * >> 8 ) & 0xFF ); + */ + *p++ = 0; + *p++ = (unsigned char)( ( 2 * ssl->conf->dtls_srtp_profile_list_len ) + & 0xFF ); + + for( protection_profiles_index=0; + protection_profiles_index < ssl->conf->dtls_srtp_profile_list_len; + protection_profiles_index++ ) + { + profile_value = mbedtls_ssl_check_srtp_profile_value + ( ssl->conf->dtls_srtp_profile_list[protection_profiles_index] ); + if( profile_value != MBEDTLS_TLS_SRTP_UNSET ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_write_use_srtp_ext, add profile: %04x", + profile_value ) ); + *p++ = ( ( profile_value >> 8 ) & 0xFF ); + *p++ = ( profile_value & 0xFF ); + } + else + { + /* + * Note: we shall never arrive here as protection profiles + * is checked by mbedtls_ssl_conf_dtls_srtp_protection_profiles function + */ + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, " + "illegal DTLS-SRTP protection profile %d", + ssl->conf->dtls_srtp_profile_list[protection_profiles_index] + ) ); + return( MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED ); + } + } + + *p++ = mki_len & 0xFF; + + if( mki_len != 0 ) + { + memcpy( p, ssl->dtls_srtp_info.mki_value, mki_len ); + /* + * Increment p to point to the current position. + */ + p += mki_len; + MBEDTLS_SSL_DEBUG_BUF( 3, "sending mki", ssl->dtls_srtp_info.mki_value, + ssl->dtls_srtp_info.mki_len ); + } + + /* + * total extension length: extension type (2 bytes) + * + extension length (2 bytes) + * + protection profile length (2 bytes) + * + 2 * number of protection profiles + * + srtp_mki vector length(1 byte) + * + mki value + */ + *olen = p - buf; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_DTLS_SRTP */ + +/* + * Generate random bytes for ClientHello + */ +static int ssl_generate_random( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + unsigned char *p = ssl->handshake->randbytes; +#if defined(MBEDTLS_HAVE_TIME) + mbedtls_time_t t; +#endif + + /* + * When responding to a verify request, MUST reuse random (RFC 6347 4.2.1) + */ +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && + ssl->handshake->verify_cookie != NULL ) + { + return( 0 ); + } +#endif + +#if defined(MBEDTLS_HAVE_TIME) + t = 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, ( "client hello, current time: %" MBEDTLS_PRINTF_LONGLONG, + (long long) t ) ); +#else + if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p, 4 ) ) != 0 ) + return( ret ); + + p += 4; +#endif /* MBEDTLS_HAVE_TIME */ + + if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p, 28 ) ) != 0 ) + return( ret ); + + return( 0 ); +} + +/** + * \brief Validate cipher suite against config in SSL context. + * + * \param suite_info cipher suite to validate + * \param ssl SSL context + * \param min_minor_ver Minimal minor version to accept a cipher suite + * \param max_minor_ver Maximal minor version to accept a cipher suite + * + * \return 0 if valid, else 1 + */ +static int ssl_validate_ciphersuite( + const mbedtls_ssl_ciphersuite_t * suite_info, + const mbedtls_ssl_context * ssl, + int min_minor_ver, int max_minor_ver ) +{ + (void) ssl; + if( suite_info == NULL ) + return( 1 ); + + if( suite_info->min_minor_ver > max_minor_ver || + suite_info->max_minor_ver < min_minor_ver ) + return( 1 ); + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && + ( suite_info->flags & MBEDTLS_CIPHERSUITE_NODTLS ) ) + return( 1 ); +#endif + +#if defined(MBEDTLS_ARC4_C) + if( ssl->conf->arc4_disabled == MBEDTLS_SSL_ARC4_DISABLED && + suite_info->cipher == MBEDTLS_CIPHER_ARC4_128 ) + return( 1 ); +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if( suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE && + mbedtls_ecjpake_check( &ssl->handshake->ecjpake_ctx ) != 0 ) + return( 1 ); +#endif + + /* Don't suggest PSK-based ciphersuite if no PSK is available. */ +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) + if( mbedtls_ssl_ciphersuite_uses_psk( suite_info ) && + ssl_conf_has_static_psk( ssl->conf ) == 0 ) + { + return( 1 ); + } +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ + + return( 0 ); +} + +static int ssl_write_client_hello( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + size_t i, n, olen, ext_len = 0; + + unsigned char *buf; + unsigned char *p, *q; + const unsigned char *end; + + unsigned char offer_compress; + const int *ciphersuites; + const mbedtls_ssl_ciphersuite_t *ciphersuite_info; +#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + int uses_ec = 0; +#endif + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write client hello" ) ); + + if( ssl->conf->f_rng == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "no RNG provided") ); + return( MBEDTLS_ERR_SSL_NO_RNG ); + } + +#if defined(MBEDTLS_SSL_RENEGOTIATION) + if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE ) +#endif + { + ssl->major_ver = ssl->conf->min_major_ver; + ssl->minor_ver = ssl->conf->min_minor_ver; + } + + if( ssl->conf->max_major_ver == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "configured max major version is invalid, consider using mbedtls_ssl_config_defaults()" ) ); + return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); + } + + buf = ssl->out_msg; + end = buf + MBEDTLS_SSL_OUT_CONTENT_LEN; + + /* + * Check if there's enough space for the first part of the ClientHello + * consisting of the 38 bytes described below, the session identifier (at + * most 32 bytes) and its length (1 byte). + * + * Use static upper bounds instead of the actual values + * to allow the compiler to optimize this away. + */ + MBEDTLS_SSL_CHK_BUF_PTR( buf, end, 38 + 1 + 32 ); + + /* + * The 38 first bytes of the ClientHello: + * 0 . 0 handshake type (written later) + * 1 . 3 handshake length (written later) + * 4 . 5 highest version supported + * 6 . 9 current UNIX time + * 10 . 37 random bytes + * + * The current UNIX time (4 bytes) and following 28 random bytes are written + * by ssl_generate_random() into ssl->handshake->randbytes buffer and then + * copied from there into the output buffer. + */ + + p = buf + 4; + mbedtls_ssl_write_version( ssl->conf->max_major_ver, + ssl->conf->max_minor_ver, + ssl->conf->transport, p ); + p += 2; + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, max version: [%d:%d]", + buf[4], buf[5] ) ); + + if( ( ret = ssl_generate_random( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_generate_random", ret ); + return( ret ); + } + + memcpy( p, ssl->handshake->randbytes, 32 ); + MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, random bytes", p, 32 ); + p += 32; + + /* + * 38 . 38 session id length + * 39 . 39+n session id + * 39+n . 39+n DTLS only: cookie length (1 byte) + * 40+n . .. DTLS only: cookie + * .. . .. ciphersuitelist length (2 bytes) + * .. . .. ciphersuitelist + * .. . .. compression methods length (1 byte) + * .. . .. compression methods + * .. . .. extensions length (2 bytes) + * .. . .. extensions + */ + n = ssl->session_negotiate->id_len; + + if( n < 16 || n > 32 || +#if defined(MBEDTLS_SSL_RENEGOTIATION) + ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE || +#endif + ssl->handshake->resume == 0 ) + { + n = 0; + } + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + /* + * RFC 5077 section 3.4: "When presenting a ticket, the client MAY + * generate and include a Session ID in the TLS ClientHello." + */ +#if defined(MBEDTLS_SSL_RENEGOTIATION) + if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE ) +#endif + { + if( ssl->session_negotiate->ticket != NULL && + ssl->session_negotiate->ticket_len != 0 ) + { + ret = ssl->conf->f_rng( ssl->conf->p_rng, + ssl->session_negotiate->id, 32 ); + + if( ret != 0 ) + return( ret ); + + ssl->session_negotiate->id_len = n = 32; + } + } +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + + /* + * The first check of the output buffer size above ( + * MBEDTLS_SSL_CHK_BUF_PTR( buf, end, 38 + 1 + 32 );) + * has checked that there is enough space in the output buffer for the + * session identifier length byte and the session identifier (n <= 32). + */ + *p++ = (unsigned char) n; + + for( i = 0; i < n; i++ ) + *p++ = ssl->session_negotiate->id[i]; + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %" MBEDTLS_PRINTF_SIZET, n ) ); + MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, session id", buf + 39, n ); + + /* + * With 'n' being the length of the session identifier + * + * 39+n . 39+n DTLS only: cookie length (1 byte) + * 40+n . .. DTLS only: cookie + * .. . .. ciphersuitelist length (2 bytes) + * .. . .. ciphersuitelist + * .. . .. compression methods length (1 byte) + * .. . .. compression methods + * .. . .. extensions length (2 bytes) + * .. . .. extensions + */ + + /* + * DTLS cookie + */ +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + { + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 1 ); + + if( ssl->handshake->verify_cookie == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "no verify cookie to send" ) ); + *p++ = 0; + } + else + { + MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, cookie", + ssl->handshake->verify_cookie, + ssl->handshake->verify_cookie_len ); + + *p++ = ssl->handshake->verify_cookie_len; + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, + ssl->handshake->verify_cookie_len ); + memcpy( p, ssl->handshake->verify_cookie, + ssl->handshake->verify_cookie_len ); + p += ssl->handshake->verify_cookie_len; + } + } +#endif + + /* + * Ciphersuite list + */ + ciphersuites = ssl->conf->ciphersuite_list[ssl->minor_ver]; + + /* Skip writing ciphersuite length for now */ + n = 0; + q = p; + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + p += 2; + + for( i = 0; ciphersuites[i] != 0; i++ ) + { + ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( ciphersuites[i] ); + + if( ssl_validate_ciphersuite( ciphersuite_info, ssl, + ssl->conf->min_minor_ver, + ssl->conf->max_minor_ver ) != 0 ) + continue; + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, add ciphersuite: %#04x (%s)", + (unsigned int)ciphersuites[i], ciphersuite_info->name ) ); + +#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + uses_ec |= mbedtls_ssl_ciphersuite_uses_ec( ciphersuite_info ); +#endif + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + + n++; + *p++ = (unsigned char)( ciphersuites[i] >> 8 ); + *p++ = (unsigned char)( ciphersuites[i] ); + } + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "client hello, got %" MBEDTLS_PRINTF_SIZET " ciphersuites (excluding SCSVs)", n ) ); + + /* + * Add TLS_EMPTY_RENEGOTIATION_INFO_SCSV + */ +#if defined(MBEDTLS_SSL_RENEGOTIATION) + if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE ) +#endif + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "adding EMPTY_RENEGOTIATION_INFO_SCSV" ) ); + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + *p++ = (unsigned char)( MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO >> 8 ); + *p++ = (unsigned char)( MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO ); + n++; + } + + /* Some versions of OpenSSL don't handle it correctly if not at end */ +#if defined(MBEDTLS_SSL_FALLBACK_SCSV) + if( ssl->conf->fallback == MBEDTLS_SSL_IS_FALLBACK ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "adding FALLBACK_SCSV" ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + *p++ = (unsigned char)( MBEDTLS_SSL_FALLBACK_SCSV_VALUE >> 8 ); + *p++ = (unsigned char)( MBEDTLS_SSL_FALLBACK_SCSV_VALUE ); + n++; + } +#endif + + *q++ = (unsigned char)( n >> 7 ); + *q++ = (unsigned char)( n << 1 ); + +#if defined(MBEDTLS_ZLIB_SUPPORT) + offer_compress = 1; +#else + offer_compress = 0; +#endif + + /* + * We don't support compression with DTLS right now: if many records come + * in the same datagram, uncompressing one could overwrite the next one. + * We don't want to add complexity for handling that case unless there is + * an actual need for it. + */ +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + offer_compress = 0; +#endif + + if( offer_compress ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress len.: %d", 2 ) ); + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress alg.: %d %d", + MBEDTLS_SSL_COMPRESS_DEFLATE, + MBEDTLS_SSL_COMPRESS_NULL ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 3 ); + *p++ = 2; + *p++ = MBEDTLS_SSL_COMPRESS_DEFLATE; + *p++ = MBEDTLS_SSL_COMPRESS_NULL; + } + else + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress len.: %d", 1 ) ); + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, compress alg.: %d", + MBEDTLS_SSL_COMPRESS_NULL ) ); + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + *p++ = 1; + *p++ = MBEDTLS_SSL_COMPRESS_NULL; + } + + /* First write extensions, then the total length */ + + MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); + +#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) + if( ( ret = ssl_write_hostname_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_hostname_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + + /* Note that TLS_EMPTY_RENEGOTIATION_INFO_SCSV is always added + * even if MBEDTLS_SSL_RENEGOTIATION is not defined. */ +#if defined(MBEDTLS_SSL_RENEGOTIATION) + if( ( ret = ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_renegotiation_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \ + defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) + if( ( ret = ssl_write_signature_algorithms_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_signature_algorithms_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if( uses_ec ) + { + if( ( ret = ssl_write_supported_elliptic_curves_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_supported_elliptic_curves_ext", ret ); + return( ret ); + } + ext_len += olen; + + if( ( ret = ssl_write_supported_point_formats_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_supported_point_formats_ext", ret ); + return( ret ); + } + ext_len += olen; + } +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if( ( ret = ssl_write_ecjpake_kkpp_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_ecjpake_kkpp_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) + if( ( ret = ssl_write_cid_ext( ssl, p + 2 + ext_len, end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_cid_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ + +#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) + if( ( ret = ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_max_fragment_length_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_TRUNCATED_HMAC) + if( ( ret = ssl_write_truncated_hmac_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_truncated_hmac_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) + if( ( ret = ssl_write_encrypt_then_mac_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_encrypt_then_mac_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) + if( ( ret = ssl_write_extended_ms_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_extended_ms_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_ALPN) + if( ( ret = ssl_write_alpn_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_alpn_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_DTLS_SRTP) + if( ( ret = ssl_write_use_srtp_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_use_srtp_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + if( ( ret = ssl_write_session_ticket_ext( ssl, p + 2 + ext_len, + end, &olen ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_session_ticket_ext", ret ); + return( ret ); + } + ext_len += olen; +#endif + + /* olen unused if all extensions are disabled */ + ((void) olen); + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %" MBEDTLS_PRINTF_SIZET, + ext_len ) ); + + if( ext_len > 0 ) + { + /* No need to check for space here, because the extension + * writing functions already took care of that. */ + *p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ext_len ) & 0xFF ); + p += ext_len; + } + + ssl->out_msglen = p - buf; + ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; + ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_HELLO; + + ssl->state++; + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + mbedtls_ssl_send_flight_completed( ssl ); +#endif + + if( ( ret = mbedtls_ssl_write_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 client hello" ) ); + + return( 0 ); +} + +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 * 2 || + buf[0] != ssl->verify_data_len * 2 || + mbedtls_ssl_safer_memcmp( buf + 1, + ssl->own_verify_data, ssl->verify_data_len ) != 0 || + mbedtls_ssl_safer_memcmp( buf + 1 + ssl->verify_data_len, + ssl->peer_verify_data, ssl->verify_data_len ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-matching renegotiation info" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + } + else +#endif /* MBEDTLS_SSL_RENEGOTIATION */ + { + if( len != 1 || buf[0] != 0x00 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-zero length renegotiation info" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION; + } + + return( 0 ); +} + +#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) +static int ssl_parse_max_fragment_length_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + /* + * server should use the extension only if we did, + * and if so the server's value should match ours (and len is always 1) + */ + if( ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE || + len != 1 || + buf[0] != ssl->conf->mfl_code ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-matching max fragment length extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + return( 0 ); +} +#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ + +#if defined(MBEDTLS_SSL_TRUNCATED_HMAC) +static int ssl_parse_truncated_hmac_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED || + len != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-matching truncated HMAC extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + ((void) buf); + + ssl->session_negotiate->trunc_hmac = MBEDTLS_SSL_TRUNC_HMAC_ENABLED; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ + +#if defined(MBEDTLS_SSL_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; + + if( /* CID extension only makes sense in DTLS */ + ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM || + /* The server must only send the CID extension if we have offered it. */ + ssl->negotiate_cid == MBEDTLS_SSL_CID_DISABLED ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "CID extension unexpected" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + if( len == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "CID extension invalid" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + peer_cid_len = *buf++; + len--; + + if( peer_cid_len > MBEDTLS_SSL_CID_OUT_LEN_MAX ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "CID extension invalid" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + if( len != peer_cid_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "CID extension invalid" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_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, "Server CID", buf, peer_cid_len ); + + return( 0 ); +} +#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ + +#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) +static int ssl_parse_encrypt_then_mac_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + if( ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED || + ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 || + len != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-matching encrypt-then-MAC extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + ((void) buf); + + ssl->session_negotiate->encrypt_then_mac = MBEDTLS_SSL_ETM_ENABLED; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ + +#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) +static int ssl_parse_extended_ms_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + if( ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED || + ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 || + len != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-matching extended master secret extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + ((void) buf); + + ssl->handshake->extended_ms = MBEDTLS_SSL_EXTENDED_MS_ENABLED; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) +static int ssl_parse_session_ticket_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + if( ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED || + len != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-matching session ticket extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + ((void) buf); + + ssl->handshake->new_session_ticket = 1; + + return( 0 ); +} +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + +#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) +static int ssl_parse_supported_point_formats_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + size_t list_size; + const unsigned char *p; + + if( len == 0 || (size_t)( buf[0] + 1 ) != len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server 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_SERVER_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++; + } + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "no point format in common" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); +} +#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || + MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) +static int ssl_parse_ecjpake_kkpp( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + + if( ssl->handshake->ciphersuite_info->key_exchange != + MBEDTLS_KEY_EXCHANGE_ECJPAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip ecjpake kkpp extension" ) ); + return( 0 ); + } + + /* If we got here, we no longer need our cached extension */ + mbedtls_free( ssl->handshake->ecjpake_cache ); + ssl->handshake->ecjpake_cache = NULL; + ssl->handshake->ecjpake_cache_len = 0; + + if( ( ret = mbedtls_ecjpake_read_round_one( &ssl->handshake->ecjpake_ctx, + buf, len ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_read_round_one", ret ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( ret ); + } + + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_SSL_ALPN) +static int ssl_parse_alpn_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, size_t len ) +{ + size_t list_len, name_len; + const char **p; + + /* If we didn't send it, the server shouldn't send it */ + if( ssl->conf->alpn_list == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "non-matching ALPN extension" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* + * opaque ProtocolName<1..2^8-1>; + * + * struct { + * ProtocolName protocol_name_list<2..2^16-1> + * } ProtocolNameList; + * + * the "ProtocolNameList" MUST contain exactly one "ProtocolName" + */ + + /* Min length is 2 (list_len) + 1 (name_len) + 1 (name) */ + if( len < 4 ) + { + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_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_SERVER_HELLO ); + } + + name_len = buf[2]; + if( name_len != list_len - 1 ) + { + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* Check that the server chosen protocol was in our list and save it */ + for( p = ssl->conf->alpn_list; *p != NULL; p++ ) + { + if( name_len == strlen( *p ) && + memcmp( buf + 3, *p, name_len ) == 0 ) + { + ssl->alpn_chosen = *p; + return( 0 ); + } + } + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "ALPN extension: no matching protocol" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); +} +#endif /* MBEDTLS_SSL_ALPN */ + +#if defined(MBEDTLS_SSL_DTLS_SRTP) +static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl, + const unsigned char *buf, + size_t len ) +{ + mbedtls_ssl_srtp_profile server_protection = MBEDTLS_TLS_SRTP_UNSET; + size_t i, mki_len = 0; + uint16_t server_protection_profile_value = 0; + + /* If use_srtp is not configured, just ignore the extension */ + if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) || + ( ssl->conf->dtls_srtp_profile_list == NULL ) || + ( ssl->conf->dtls_srtp_profile_list_len == 0 ) ) + return( 0 ); + + /* RFC 5764 section 4.1.1 + * uint8 SRTPProtectionProfile[2]; + * + * struct { + * SRTPProtectionProfiles SRTPProtectionProfiles; + * opaque srtp_mki<0..255>; + * } UseSRTPData; + + * SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>; + * + */ + if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED ) + { + mki_len = ssl->dtls_srtp_info.mki_len; + } + + /* + * Length is 5 + optional mki_value : one protection profile length (2 bytes) + * + protection profile (2 bytes) + * + mki_len(1 byte) + * and optional srtp_mki + */ + if( ( len < 5 ) || ( len != ( buf[4] + 5u ) ) ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + + /* + * get the server protection profile + */ + + /* + * protection profile length must be 0x0002 as we must have only + * one protection profile in server Hello + */ + if( ( buf[0] != 0 ) || ( buf[1] != 2 ) ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + + server_protection_profile_value = ( buf[2] << 8 ) | buf[3]; + server_protection = mbedtls_ssl_check_srtp_profile_value( + server_protection_profile_value ); + if( server_protection != MBEDTLS_TLS_SRTP_UNSET ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found srtp profile: %s", + mbedtls_ssl_get_srtp_profile_as_string( + server_protection ) ) ); + } + + ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_TLS_SRTP_UNSET; + + /* + * Check we have the server profile in our list + */ + for( i=0; i < ssl->conf->dtls_srtp_profile_list_len; i++) + { + if( server_protection == ssl->conf->dtls_srtp_profile_list[i] ) + { + ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i]; + MBEDTLS_SSL_DEBUG_MSG( 3, ( "selected srtp profile: %s", + mbedtls_ssl_get_srtp_profile_as_string( + server_protection ) ) ); + break; + } + } + + /* If no match was found : server problem, it shall never answer with incompatible profile */ + if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_TLS_SRTP_UNSET ) + { + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* If server does not use mki in its reply, make sure the client won't keep + * one as negotiated */ + if( len == 5 ) + { + ssl->dtls_srtp_info.mki_len = 0; + } + + /* + * RFC5764: + * If the client detects a nonzero-length MKI in the server's response + * that is different than the one the client offered, then the client + * MUST abort the handshake and SHOULD send an invalid_parameter alert. + */ + if( len > 5 && ( buf[4] != mki_len || + ( memcmp( ssl->dtls_srtp_info.mki_value, &buf[5], mki_len ) ) ) ) + { + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } +#if defined (MBEDTLS_DEBUG_C) + if( len > 5 ) + { + MBEDTLS_SSL_DEBUG_BUF( 3, "received mki", ssl->dtls_srtp_info.mki_value, + ssl->dtls_srtp_info.mki_len ); + } +#endif + return( 0 ); +} +#endif /* MBEDTLS_SSL_DTLS_SRTP */ + +/* + * Parse HelloVerifyRequest. Only called after verifying the HS type. + */ +#if defined(MBEDTLS_SSL_PROTO_DTLS) +static int ssl_parse_hello_verify_request( mbedtls_ssl_context *ssl ) +{ + const unsigned char *p = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ); + int major_ver, minor_ver; + unsigned char cookie_len; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse hello verify request" ) ); + + /* Check that there is enough room for: + * - 2 bytes of version + * - 1 byte of cookie_len + */ + if( mbedtls_ssl_hs_hdr_len( ssl ) + 3 > ssl->in_msglen ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "incoming HelloVerifyRequest message is too short" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* + * struct { + * ProtocolVersion server_version; + * opaque cookie<0..2^8-1>; + * } HelloVerifyRequest; + */ + MBEDTLS_SSL_DEBUG_BUF( 3, "server version", p, 2 ); + mbedtls_ssl_read_version( &major_ver, &minor_ver, ssl->conf->transport, p ); + p += 2; + + /* + * Since the RFC is not clear on this point, accept DTLS 1.0 (TLS 1.1) + * even is lower than our min version. + */ + if( major_ver < MBEDTLS_SSL_MAJOR_VERSION_3 || + minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 || + major_ver > ssl->conf->max_major_ver || + minor_ver > ssl->conf->max_minor_ver ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server version" ) ); + + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION ); + + return( MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION ); + } + + cookie_len = *p++; + if( ( ssl->in_msg + ssl->in_msglen ) - p < cookie_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "cookie length does not match incoming message size" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + MBEDTLS_SSL_DEBUG_BUF( 3, "cookie", p, cookie_len ); + + mbedtls_free( ssl->handshake->verify_cookie ); + + ssl->handshake->verify_cookie = mbedtls_calloc( 1, cookie_len ); + if( ssl->handshake->verify_cookie == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc failed (%d bytes)", cookie_len ) ); + return( MBEDTLS_ERR_SSL_ALLOC_FAILED ); + } + + memcpy( ssl->handshake->verify_cookie, p, cookie_len ); + ssl->handshake->verify_cookie_len = cookie_len; + + /* Start over at ClientHello */ + ssl->state = MBEDTLS_SSL_CLIENT_HELLO; + mbedtls_ssl_reset_checksum( ssl ); + + mbedtls_ssl_recv_flight_completed( ssl ); + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse hello verify request" ) ); + + return( 0 ); +} +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + +static int ssl_parse_server_hello( mbedtls_ssl_context *ssl ) +{ + int ret, i; + size_t n; + size_t ext_len; + unsigned char *buf, *ext; + unsigned char comp; +#if defined(MBEDTLS_ZLIB_SUPPORT) + int accept_comp; +#endif +#if defined(MBEDTLS_SSL_RENEGOTIATION) + int renegotiation_info_seen = 0; +#endif + int handshake_failure = 0; + const mbedtls_ssl_ciphersuite_t *suite_info; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server hello" ) ); + + if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) + { + /* No alert on a read error. */ + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); + return( ret ); + } + + buf = ssl->in_msg; + + if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) + { +#if defined(MBEDTLS_SSL_RENEGOTIATION) + if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS ) + { + ssl->renego_records_seen++; + + if( ssl->conf->renego_max_records >= 0 && + ssl->renego_records_seen > ssl->conf->renego_max_records ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "renegotiation requested, but not honored by server" ) ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "non-handshake message during renegotiation" ) ); + + ssl->keep_current_message = 1; + return( MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO ); + } +#endif /* MBEDTLS_SSL_RENEGOTIATION */ + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + { + if( buf[0] == MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "received hello verify request" ) ); + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello" ) ); + return( ssl_parse_hello_verify_request( ssl ) ); + } + else + { + /* We made it through the verification process */ + mbedtls_free( ssl->handshake->verify_cookie ); + ssl->handshake->verify_cookie = NULL; + ssl->handshake->verify_cookie_len = 0; + } + } +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + + if( ssl->in_hslen < 38 + mbedtls_ssl_hs_hdr_len( ssl ) || + buf[0] != MBEDTLS_SSL_HS_SERVER_HELLO ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* + * 0 . 1 server_version + * 2 . 33 random (maybe including 4 bytes of Unix time) + * 34 . 34 session_id length = n + * 35 . 34+n session_id + * 35+n . 36+n cipher_suite + * 37+n . 37+n compression_method + * + * 38+n . 39+n extensions length (optional) + * 40+n . .. extensions + */ + buf += mbedtls_ssl_hs_hdr_len( ssl ); + + MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, version", buf + 0, 2 ); + mbedtls_ssl_read_version( &ssl->major_ver, &ssl->minor_ver, + ssl->conf->transport, buf + 0 ); + + if( ssl->major_ver < ssl->conf->min_major_ver || + ssl->minor_ver < ssl->conf->min_minor_ver || + ssl->major_ver > ssl->conf->max_major_ver || + ssl->minor_ver > ssl->conf->max_minor_ver ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "server version out of bounds - min: [%d:%d], server: [%d:%d], max: [%d:%d]", + ssl->conf->min_major_ver, + ssl->conf->min_minor_ver, + ssl->major_ver, ssl->minor_ver, + ssl->conf->max_major_ver, + ssl->conf->max_minor_ver ) ); + + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION ); + + return( MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION ); + } + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, current time: %lu", + ( (unsigned long) buf[2] << 24 ) | + ( (unsigned long) buf[3] << 16 ) | + ( (unsigned long) buf[4] << 8 ) | + ( (unsigned long) buf[5] ) ) ); + + memcpy( ssl->handshake->randbytes + 32, buf + 2, 32 ); + + n = buf[34]; + + MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 2, 32 ); + + if( n > 32 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + if( ssl->in_hslen > mbedtls_ssl_hs_hdr_len( ssl ) + 39 + n ) + { + ext_len = ( ( buf[38 + n] << 8 ) + | ( buf[39 + n] ) ); + + if( ( ext_len > 0 && ext_len < 4 ) || + ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) + 40 + n + ext_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + } + else if( ssl->in_hslen == mbedtls_ssl_hs_hdr_len( ssl ) + 38 + n ) + { + ext_len = 0; + } + else + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + /* ciphersuite (used later) */ + i = ( buf[35 + n] << 8 ) | buf[36 + n]; + + /* + * Read and check compression + */ + comp = buf[37 + n]; + +#if defined(MBEDTLS_ZLIB_SUPPORT) + /* See comments in ssl_write_client_hello() */ +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + accept_comp = 0; + else +#endif + accept_comp = 1; + + if( comp != MBEDTLS_SSL_COMPRESS_NULL && + ( comp != MBEDTLS_SSL_COMPRESS_DEFLATE || accept_comp == 0 ) ) +#else /* MBEDTLS_ZLIB_SUPPORT */ + if( comp != MBEDTLS_SSL_COMPRESS_NULL ) +#endif/* MBEDTLS_ZLIB_SUPPORT */ + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "server hello, bad compression: %d", comp ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); + } + + /* + * Initialize update checksum functions + */ + ssl->handshake->ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( i ); + if( ssl->handshake->ciphersuite_info == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "ciphersuite info for %04x not found", (unsigned int)i ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); + } + + mbedtls_ssl_optimize_checksum( ssl, ssl->handshake->ciphersuite_info ); + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %" MBEDTLS_PRINTF_SIZET, n ) ); + MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, session id", buf + 35, n ); + + /* + * Check if the session can be resumed + */ + if( ssl->handshake->resume == 0 || n == 0 || +#if defined(MBEDTLS_SSL_RENEGOTIATION) + ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE || +#endif + ssl->session_negotiate->ciphersuite != i || + ssl->session_negotiate->compression != comp || + ssl->session_negotiate->id_len != n || + memcmp( ssl->session_negotiate->id, buf + 35, n ) != 0 ) + { + ssl->state++; + ssl->handshake->resume = 0; +#if defined(MBEDTLS_HAVE_TIME) + ssl->session_negotiate->start = mbedtls_time( NULL ); +#endif + ssl->session_negotiate->ciphersuite = i; + ssl->session_negotiate->compression = comp; + ssl->session_negotiate->id_len = n; + memcpy( ssl->session_negotiate->id, buf + 35, n ); + } + else + { + ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC; + + if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR ); + return( ret ); + } + } + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "%s session has been resumed", + ssl->handshake->resume ? "a" : "no" ) ); + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: %04x", (unsigned) i ) ); + MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d", + buf[37 + n] ) ); + + /* + * Perform cipher suite validation in same way as in ssl_write_client_hello. + */ + i = 0; + while( 1 ) + { + if( ssl->conf->ciphersuite_list[ssl->minor_ver][i] == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server 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_SERVER_HELLO ); + } + + if( ssl->conf->ciphersuite_list[ssl->minor_ver][i++] == + ssl->session_negotiate->ciphersuite ) + { + break; + } + } + + suite_info = mbedtls_ssl_ciphersuite_from_id( + ssl->session_negotiate->ciphersuite ); + if( ssl_validate_ciphersuite( suite_info, ssl, ssl->minor_ver, + ssl->minor_ver ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server 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_SERVER_HELLO ); + } + + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "server hello, chosen ciphersuite: %s", suite_info->name ) ); + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA && + ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) + { + ssl->handshake->ecrs_enabled = 1; + } +#endif + + if( comp != MBEDTLS_SSL_COMPRESS_NULL +#if defined(MBEDTLS_ZLIB_SUPPORT) + && comp != MBEDTLS_SSL_COMPRESS_DEFLATE +#endif + ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + ssl->session_negotiate->compression = comp; + + ext = buf + 40 + n; + + MBEDTLS_SSL_DEBUG_MSG( 2, + ( "server hello, total extension length: %" MBEDTLS_PRINTF_SIZET, ext_len ) ); + + while( ext_len ) + { + unsigned int ext_id = ( ( ext[0] << 8 ) + | ( ext[1] ) ); + unsigned int ext_size = ( ( ext[2] << 8 ) + | ( ext[3] ) ); + + if( ext_size + 4 > ext_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + mbedtls_ssl_send_alert_message( + ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + switch( ext_id ) + { + case MBEDTLS_TLS_EXT_RENEGOTIATION_INFO: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found renegotiation extension" ) ); +#if defined(MBEDTLS_SSL_RENEGOTIATION) + renegotiation_info_seen = 1; +#endif + + if( ( ret = ssl_parse_renegotiation_info( ssl, ext + 4, + ext_size ) ) != 0 ) + return( ret ); + + break; + +#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) + case MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH: + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "found max_fragment_length extension" ) ); + + if( ( ret = ssl_parse_max_fragment_length_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ + +#if defined(MBEDTLS_SSL_TRUNCATED_HMAC) + case MBEDTLS_TLS_EXT_TRUNCATED_HMAC: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found truncated_hmac extension" ) ); + + if( ( ret = ssl_parse_truncated_hmac_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ + +#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) + case MBEDTLS_TLS_EXT_CID: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found CID extension" ) ); + + if( ( ret = ssl_parse_cid_ext( ssl, + ext + 4, + ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ + +#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) + case MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found encrypt_then_mac extension" ) ); + + if( ( ret = ssl_parse_encrypt_then_mac_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ + +#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) + case MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET: + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "found extended_master_secret extension" ) ); + + if( ( ret = ssl_parse_extended_ms_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + case MBEDTLS_TLS_EXT_SESSION_TICKET: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found session_ticket extension" ) ); + + if( ( ret = ssl_parse_session_ticket_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + +#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + case MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS: + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "found supported_point_formats extension" ) ); + + if( ( ret = ssl_parse_supported_point_formats_ext( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C || + MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + case MBEDTLS_TLS_EXT_ECJPAKE_KKPP: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found ecjpake_kkpp extension" ) ); + + if( ( ret = ssl_parse_ecjpake_kkpp( ssl, + ext + 4, ext_size ) ) != 0 ) + { + return( ret ); + } + + break; +#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + +#if defined(MBEDTLS_SSL_ALPN) + case MBEDTLS_TLS_EXT_ALPN: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found alpn extension" ) ); + + if( ( ret = ssl_parse_alpn_ext( ssl, ext + 4, ext_size ) ) != 0 ) + return( ret ); + + break; +#endif /* MBEDTLS_SSL_ALPN */ + +#if defined(MBEDTLS_SSL_DTLS_SRTP) + case MBEDTLS_TLS_EXT_USE_SRTP: + MBEDTLS_SSL_DEBUG_MSG( 3, ( "found use_srtp extension" ) ); + + if( ( ret = ssl_parse_use_srtp_ext( ssl, ext + 4, ext_size ) ) != 0 ) + return( ret ); + + break; +#endif /* MBEDTLS_SSL_DTLS_SRTP */ + + default: + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "unknown extension found: %u (ignoring)", ext_id ) ); + } + + ext_len -= 4 + ext_size; + ext += 4 + ext_size; + + if( ext_len > 0 && ext_len < 4 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello message" ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + } + + /* + * Renegotiation security checks + */ + if( ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION && + ssl->conf->allow_legacy_renegotiation == + MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "legacy renegotiation, breaking off handshake" ) ); + handshake_failure = 1; + } +#if defined(MBEDTLS_SSL_RENEGOTIATION) + else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS && + ssl->secure_renegotiation == MBEDTLS_SSL_SECURE_RENEGOTIATION && + renegotiation_info_seen == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "renegotiation_info extension missing (secure)" ) ); + handshake_failure = 1; + } + else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS && + ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION && + ssl->conf->allow_legacy_renegotiation == + MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "legacy renegotiation not allowed" ) ); + handshake_failure = 1; + } + else if( ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS && + ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION && + renegotiation_info_seen == 1 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "renegotiation_info extension present (legacy)" ) ); + handshake_failure = 1; + } +#endif /* MBEDTLS_SSL_RENEGOTIATION */ + + if( handshake_failure == 1 ) + { + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO ); + } + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello" ) ); + + return( 0 ); +} + +#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) +static int ssl_parse_server_dh_params( mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end ) +{ + int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + size_t dhm_actual_bitlen; + + /* + * Ephemeral DH parameters: + * + * struct { + * opaque dh_p<1..2^16-1>; + * opaque dh_g<1..2^16-1>; + * opaque dh_Ys<1..2^16-1>; + * } ServerDHParams; + */ + if( ( ret = mbedtls_dhm_read_params( &ssl->handshake->dhm_ctx, + p, end ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 2, ( "mbedtls_dhm_read_params" ), ret ); + return( ret ); + } + + dhm_actual_bitlen = mbedtls_mpi_bitlen( &ssl->handshake->dhm_ctx.P ); + if( dhm_actual_bitlen < ssl->conf->dhm_min_bitlen ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "DHM prime too short: %" MBEDTLS_PRINTF_SIZET " < %u", + dhm_actual_bitlen, + ssl->conf->dhm_min_bitlen ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: P ", &ssl->handshake->dhm_ctx.P ); + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: G ", &ssl->handshake->dhm_ctx.G ); + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: GY", &ssl->handshake->dhm_ctx.GY ); + + return( ret ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) +static int ssl_check_server_ecdh_params( const mbedtls_ssl_context *ssl ) +{ + const mbedtls_ecp_curve_info *curve_info; + mbedtls_ecp_group_id grp_id; +#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT) + grp_id = ssl->handshake->ecdh_ctx.grp.id; +#else + grp_id = ssl->handshake->ecdh_ctx.grp_id; +#endif + + curve_info = mbedtls_ecp_curve_info_from_grp_id( grp_id ); + if( curve_info == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "ECDH curve: %s", curve_info->name ) ); + +#if defined(MBEDTLS_ECP_C) + if( mbedtls_ssl_check_curve( ssl, grp_id ) != 0 ) +#else + if( ssl->handshake->ecdh_ctx.grp.nbits < 163 || + ssl->handshake->ecdh_ctx.grp.nbits > 521 ) +#endif + return( -1 ); + + MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, + MBEDTLS_DEBUG_ECDH_QP ); + + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */ + +#if defined(MBEDTLS_USE_PSA_CRYPTO) && \ + ( defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ) +static int ssl_parse_server_ecdh_params_psa( mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end ) +{ + uint16_t tls_id; + size_t ecdh_bits = 0; + uint8_t ecpoint_len; + mbedtls_ssl_handshake_params *handshake = ssl->handshake; + + /* + * Parse ECC group + */ + + if( end - *p < 4 ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + + /* First byte is curve_type; only named_curve is handled */ + if( *(*p)++ != MBEDTLS_ECP_TLS_NAMED_CURVE ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + + /* Next two bytes are the namedcurve value */ + tls_id = *(*p)++; + tls_id <<= 8; + tls_id |= *(*p)++; + + /* Convert EC group to PSA key type. */ + if( ( handshake->ecdh_psa_type = + mbedtls_psa_parse_tls_ecc_group( tls_id, &ecdh_bits ) ) == 0 ) + { + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + if( ecdh_bits > 0xffff ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + handshake->ecdh_bits = (uint16_t) ecdh_bits; + + /* + * Put peer's ECDH public key in the format understood by PSA. + */ + + ecpoint_len = *(*p)++; + if( (size_t)( end - *p ) < ecpoint_len ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + + if( mbedtls_psa_tls_ecpoint_to_psa_ec( + *p, ecpoint_len, + handshake->ecdh_psa_peerkey, + sizeof( handshake->ecdh_psa_peerkey ), + &handshake->ecdh_psa_peerkey_len ) != 0 ) + { + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + } + + *p += ecpoint_len; + return( 0 ); +} +#endif /* MBEDTLS_USE_PSA_CRYPTO && + ( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) +static int ssl_parse_server_ecdh_params( mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end ) +{ + int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + + /* + * Ephemeral ECDH parameters: + * + * struct { + * ECParameters curve_params; + * ECPoint public; + * } ServerECDHParams; + */ + if( ( ret = mbedtls_ecdh_read_params( &ssl->handshake->ecdh_ctx, + (const unsigned char **) p, end ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_read_params" ), ret ); +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS ) + ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS; +#endif + return( ret ); + } + + if( ssl_check_server_ecdh_params( ssl ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "bad server key exchange message (ECDHE curve)" ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + return( ret ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) +static int ssl_parse_server_psk_hint( mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end ) +{ + int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + uint16_t len; + ((void) ssl); + + /* + * PSK parameters: + * + * opaque psk_identity_hint<0..2^16-1>; + */ + if( end - (*p) < 2 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "bad server key exchange message (psk_identity_hint length)" ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + len = (*p)[0] << 8 | (*p)[1]; + *p += 2; + + if( end - (*p) < len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "bad server key exchange message (psk_identity_hint length)" ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + /* + * Note: we currently ignore the PKS identity hint, as we only allow one + * PSK to be provisionned on the client. This could be changed later if + * someone needs that feature. + */ + *p += len; + ret = 0; + + return( ret ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) +/* + * Generate a pre-master secret and encrypt it with the server's RSA key + */ +static int ssl_write_encrypted_pms( mbedtls_ssl_context *ssl, + size_t offset, size_t *olen, + size_t pms_offset ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + size_t len_bytes = ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ? 0 : 2; + unsigned char *p = ssl->handshake->premaster + pms_offset; + mbedtls_pk_context * peer_pk; + + if( offset + len_bytes > MBEDTLS_SSL_OUT_CONTENT_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small for encrypted pms" ) ); + return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL ); + } + + /* + * Generate (part of) the pre-master as + * struct { + * ProtocolVersion client_version; + * opaque random[46]; + * } PreMasterSecret; + */ + mbedtls_ssl_write_version( ssl->conf->max_major_ver, + ssl->conf->max_minor_ver, + ssl->conf->transport, p ); + + if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, p + 2, 46 ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "f_rng", ret ); + return( ret ); + } + + ssl->handshake->pmslen = 48; + +#if !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 */ + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + peer_pk = &ssl->session_negotiate->peer_cert->pk; +#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + + /* + * Now write it out, encrypted + */ + if( ! mbedtls_pk_can_do( peer_pk, MBEDTLS_PK_RSA ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "certificate key type mismatch" ) ); + return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH ); + } + + if( ( ret = mbedtls_pk_encrypt( peer_pk, + p, ssl->handshake->pmslen, + ssl->out_msg + offset + len_bytes, olen, + MBEDTLS_SSL_OUT_CONTENT_LEN - offset - len_bytes, + ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_rsa_pkcs1_encrypt", ret ); + return( ret ); + } + +#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \ + defined(MBEDTLS_SSL_PROTO_TLS1_2) + if( len_bytes == 2 ) + { + ssl->out_msg[offset+0] = (unsigned char)( *olen >> 8 ); + ssl->out_msg[offset+1] = (unsigned char)( *olen ); + *olen += 2; + } +#endif + +#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) + /* We don't need the peer's public key anymore. Free it. */ + mbedtls_pk_free( peer_pk ); +#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */ + +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) +#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) +static int ssl_parse_signature_algorithm( mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end, + mbedtls_md_type_t *md_alg, + mbedtls_pk_type_t *pk_alg ) +{ + ((void) ssl); + *md_alg = MBEDTLS_MD_NONE; + *pk_alg = MBEDTLS_PK_NONE; + + /* Only in TLS 1.2 */ + if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 ) + { + return( 0 ); + } + + if( (*p) + 2 > end ) + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + + /* + * Get hash algorithm + */ + if( ( *md_alg = mbedtls_ssl_md_alg_from_hash( (*p)[0] ) ) + == MBEDTLS_MD_NONE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "Server used unsupported HashAlgorithm %d", *(p)[0] ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + /* + * Get signature algorithm + */ + if( ( *pk_alg = mbedtls_ssl_pk_alg_from_sig( (*p)[1] ) ) + == MBEDTLS_PK_NONE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "server used unsupported SignatureAlgorithm %d", (*p)[1] ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + /* + * Check if the hash is acceptable + */ + if( mbedtls_ssl_check_sig_hash( ssl, *md_alg ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "server used HashAlgorithm %d that was not offered", *(p)[0] ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "Server used SignatureAlgorithm %d", + (*p)[1] ) ); + MBEDTLS_SSL_DEBUG_MSG( 2, ( "Server used HashAlgorithm %d", + (*p)[0] ) ); + *p += 2; + + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ +#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) +static int ssl_get_ecdh_params_from_cert( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + const mbedtls_ecp_keypair *peer_key; + mbedtls_pk_context * peer_pk; + +#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 */ + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + peer_pk = &ssl->session_negotiate->peer_cert->pk; +#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + + if( ! mbedtls_pk_can_do( peer_pk, MBEDTLS_PK_ECKEY ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "server key not ECDH capable" ) ); + return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH ); + } + + peer_key = mbedtls_pk_ec( *peer_pk ); + + if( ( ret = mbedtls_ecdh_get_params( &ssl->handshake->ecdh_ctx, peer_key, + MBEDTLS_ECDH_THEIRS ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_get_params" ), ret ); + return( ret ); + } + + if( ssl_check_server_ecdh_params( ssl ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server certificate (ECDH curve)" ) ); + return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE ); + } + +#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) + /* We don't need the peer's public key anymore. Free it, + * so that more RAM is available for upcoming expensive + * operations like ECDHE. */ + mbedtls_pk_free( peer_pk ); +#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + + return( ret ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || + MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */ + +static int ssl_parse_server_key_exchange( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + unsigned char *p = NULL, *end = NULL; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server key exchange" ) ); + +#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) ); + ssl->state++; + return( 0 ); + } + ((void) p); + ((void) end); +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA ) + { + if( ( ret = ssl_get_ecdh_params_from_cert( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "ssl_get_ecdh_params_from_cert", ret ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( ret ); + } + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse server key exchange" ) ); + ssl->state++; + return( 0 ); + } + ((void) p); + ((void) end); +#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */ + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled && + ssl->handshake->ecrs_state == ssl_ecrs_ske_start_processing ) + { + goto start_processing; + } +#endif + + if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); + return( ret ); + } + + if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + + /* + * ServerKeyExchange may be skipped with PSK and RSA-PSK when the server + * doesn't use a psk_identity_hint + */ + if( ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE ) + { + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ) + { + /* Current message is probably either + * CertificateRequest or ServerHelloDone */ + ssl->keep_current_message = 1; + goto exit; + } + + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "server key exchange message must not be skipped" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); + + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + ssl->handshake->ecrs_state = ssl_ecrs_ske_start_processing; + +start_processing: +#endif + p = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ); + end = ssl->in_msg + ssl->in_hslen; + MBEDTLS_SSL_DEBUG_BUF( 3, "server key exchange", p, end - p ); + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ) + { + if( ssl_parse_server_psk_hint( ssl, &p, end ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } /* FALLTROUGH */ +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ) + ; /* nothing more to do */ + else +#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED || + MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */ +#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ) + { + if( ssl_parse_server_dh_params( ssl, &p, end ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */ +#if defined(MBEDTLS_USE_PSA_CRYPTO) && \ + ( defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ) + { + if( ssl_parse_server_ecdh_params_psa( ssl, &p, end ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } + else +#endif /* MBEDTLS_USE_PSA_CRYPTO && + ( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */ +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ) + { + if( ssl_parse_server_ecdh_params( ssl, &p, end ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE ) + { + ret = mbedtls_ecjpake_read_round_two( &ssl->handshake->ecjpake_ctx, + p, end - p ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_read_round_two", ret ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + +#if defined(MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED) + if( mbedtls_ssl_ciphersuite_uses_server_signature( ciphersuite_info ) ) + { + size_t sig_len, hashlen; + unsigned char hash[64]; + mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE; + mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE; + unsigned char *params = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ); + size_t params_len = p - params; + void *rs_ctx = NULL; + + mbedtls_pk_context * peer_pk; + + /* + * Handle the digitally-signed structure + */ +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) + if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) + { + if( ssl_parse_signature_algorithm( ssl, &p, end, + &md_alg, &pk_alg ) != 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + if( pk_alg != + mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + } + else +#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ +#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \ + defined(MBEDTLS_SSL_PROTO_TLS1_1) + if( ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_3 ) + { + pk_alg = mbedtls_ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info ); + + /* Default hash for ECDSA is SHA-1 */ + if( pk_alg == MBEDTLS_PK_ECDSA && md_alg == MBEDTLS_MD_NONE ) + md_alg = MBEDTLS_MD_SHA1; + } + else +#endif + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + + /* + * Read signature + */ + + if( p > end - 2 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + sig_len = ( p[0] << 8 ) | p[1]; + p += 2; + + if( p != end - sig_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE ); + } + + MBEDTLS_SSL_DEBUG_BUF( 3, "signature", p, sig_len ); + + /* + * Compute the hash that has been signed + */ +#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \ + defined(MBEDTLS_SSL_PROTO_TLS1_1) + if( md_alg == MBEDTLS_MD_NONE ) + { + hashlen = 36; + ret = mbedtls_ssl_get_key_exchange_md_ssl_tls( ssl, hash, params, + params_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, + params, params_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 ); + +#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 */ + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + peer_pk = &ssl->session_negotiate->peer_cert->pk; +#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + + /* + * Verify signature + */ + if( !mbedtls_pk_can_do( peer_pk, pk_alg ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE ); + return( MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH ); + } + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + rs_ctx = &ssl->handshake->ecrs_ctx.pk; +#endif + + if( ( ret = mbedtls_pk_verify_restartable( peer_pk, + md_alg, hash, hashlen, p, sig_len, rs_ctx ) ) != 0 ) + { +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS ) +#endif + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR ); + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_verify", ret ); +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS ) + ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS; +#endif + return( ret ); + } + +#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) + /* We don't need the peer's public key anymore. Free it, + * so that more RAM is available for upcoming expensive + * operations like ECDHE. */ + mbedtls_pk_free( peer_pk ); +#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ + } +#endif /* MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED */ + +exit: + ssl->state++; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server key exchange" ) ); + + return( 0 ); +} + +#if ! defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED) +static int ssl_parse_certificate_request( mbedtls_ssl_context *ssl ) +{ + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate request" ) ); + + if( ! mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate request" ) ); + ssl->state++; + return( 0 ); + } + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); +} +#else /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ +static int ssl_parse_certificate_request( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + unsigned char *buf; + size_t n = 0; + size_t cert_type_len = 0, dn_len = 0; + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse certificate request" ) ); + + if( ! mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip parse certificate request" ) ); + ssl->state++; + return( 0 ); + } + + if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); + return( ret ); + } + + if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + + ssl->state++; + ssl->client_auth = ( ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE_REQUEST ); + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "got %s certificate request", + ssl->client_auth ? "a" : "no" ) ); + + if( ssl->client_auth == 0 ) + { + /* Current message is probably the ServerHelloDone */ + ssl->keep_current_message = 1; + goto exit; + } + + /* + * struct { + * ClientCertificateType certificate_types<1..2^8-1>; + * SignatureAndHashAlgorithm + * supported_signature_algorithms<2^16-1>; -- TLS 1.2 only + * DistinguishedName certificate_authorities<0..2^16-1>; + * } CertificateRequest; + * + * Since we only support a single certificate on clients, let's just + * ignore all the information that's supposed to help us pick a + * certificate. + * + * We could check that our certificate matches the request, and bail out + * if it doesn't, but it's simpler to just send the certificate anyway, + * and give the server the opportunity to decide if it should terminate + * the connection when it doesn't like our certificate. + * + * Same goes for the hash in TLS 1.2's signature_algorithms: at this + * point we only have one hash available (see comments in + * write_certificate_verify), so let's just use what we have. + * + * However, we still minimally parse the message to check it is at least + * superficially sane. + */ + buf = ssl->in_msg; + + /* certificate_types */ + if( ssl->in_hslen <= mbedtls_ssl_hs_hdr_len( ssl ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST ); + } + cert_type_len = buf[mbedtls_ssl_hs_hdr_len( ssl )]; + n = cert_type_len; + + /* + * In the subsequent code there are two paths that read from buf: + * * the length of the signature algorithms field (if minor version of + * SSL is 3), + * * distinguished name length otherwise. + * Both reach at most the index: + * ...hdr_len + 2 + n, + * therefore the buffer length at this point must be greater than that + * regardless of the actual code path. + */ + if( ssl->in_hslen <= mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST ); + } + + /* supported_signature_algorithms */ +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) + if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) + { + size_t sig_alg_len = + ( ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 1 + n] << 8 ) + | ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n] ) ); +#if defined(MBEDTLS_DEBUG_C) + unsigned char* sig_alg; + size_t i; +#endif + + /* + * The furthest access in buf is in the loop few lines below: + * sig_alg[i + 1], + * where: + * sig_alg = buf + ...hdr_len + 3 + n, + * max(i) = sig_alg_len - 1. + * Therefore the furthest access is: + * buf[...hdr_len + 3 + n + sig_alg_len - 1 + 1], + * which reduces to: + * buf[...hdr_len + 3 + n + sig_alg_len], + * which is one less than we need the buf to be. + */ + if( ssl->in_hslen <= mbedtls_ssl_hs_hdr_len( ssl ) + + 3 + n + sig_alg_len ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST ); + } + +#if defined(MBEDTLS_DEBUG_C) + sig_alg = buf + mbedtls_ssl_hs_hdr_len( ssl ) + 3 + n; + for( i = 0; i < sig_alg_len; i += 2 ) + { + MBEDTLS_SSL_DEBUG_MSG( 3, + ( "Supported Signature Algorithm found: %d,%d", + sig_alg[i], sig_alg[i + 1] ) ); + } +#endif + + n += 2 + sig_alg_len; + } +#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ + + /* certificate_authorities */ + dn_len = ( ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 1 + n] << 8 ) + | ( buf[mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n] ) ); + + n += dn_len; + if( ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) + 3 + n ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST ); + } + +exit: + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse certificate request" ) ); + + return( 0 ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ + +static int ssl_parse_server_hello_done( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse server hello done" ) ); + + if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); + return( ret ); + } + + if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + + if( ssl->in_hslen != mbedtls_ssl_hs_hdr_len( ssl ) || + ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_HELLO_DONE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server hello done message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE ); + } + + ssl->state++; + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) + mbedtls_ssl_recv_flight_completed( ssl ); +#endif + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse server hello done" ) ); + + return( 0 ); +} + +static int ssl_write_client_key_exchange( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + + size_t header_len; + size_t content_len; + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write client key exchange" ) ); + +#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA ) + { + /* + * DHM key exchange -- send G^X mod P + */ + content_len = ssl->handshake->dhm_ctx.len; + + ssl->out_msg[4] = (unsigned char)( content_len >> 8 ); + ssl->out_msg[5] = (unsigned char)( content_len ); + header_len = 6; + + ret = mbedtls_dhm_make_public( &ssl->handshake->dhm_ctx, + (int) mbedtls_mpi_size( &ssl->handshake->dhm_ctx.P ), + &ssl->out_msg[header_len], content_len, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_make_public", ret ); + return( ret ); + } + + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: X ", &ssl->handshake->dhm_ctx.X ); + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: GX", &ssl->handshake->dhm_ctx.GX ); + + if( ( ret = mbedtls_dhm_calc_secret( &ssl->handshake->dhm_ctx, + ssl->handshake->premaster, + MBEDTLS_PREMASTER_SIZE, + &ssl->handshake->pmslen, + ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_calc_secret", ret ); + return( ret ); + } + + MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K ); + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */ +#if defined(MBEDTLS_USE_PSA_CRYPTO) && \ + ( defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ) + { + psa_status_t status; + psa_key_attributes_t key_attributes; + + mbedtls_ssl_handshake_params *handshake = ssl->handshake; + + unsigned char own_pubkey[MBEDTLS_PSA_MAX_EC_PUBKEY_LENGTH]; + size_t own_pubkey_len; + unsigned char *own_pubkey_ecpoint; + size_t own_pubkey_ecpoint_len; + + header_len = 4; + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "Perform PSA-based ECDH computation." ) ); + + /* + * Generate EC private key for ECDHE exchange. + */ + + /* The master secret is obtained from the shared ECDH secret by + * applying the TLS 1.2 PRF with a specific salt and label. While + * the PSA Crypto API encourages combining key agreement schemes + * such as ECDH with fixed KDFs such as TLS 1.2 PRF, it does not + * yet support the provisioning of salt + label to the KDF. + * For the time being, we therefore need to split the computation + * of the ECDH secret and the application of the TLS 1.2 PRF. */ + key_attributes = psa_key_attributes_init(); + psa_set_key_usage_flags( &key_attributes, PSA_KEY_USAGE_DERIVE ); + psa_set_key_algorithm( &key_attributes, PSA_ALG_ECDH ); + psa_set_key_type( &key_attributes, handshake->ecdh_psa_type ); + psa_set_key_bits( &key_attributes, handshake->ecdh_bits ); + + /* Generate ECDH private key. */ + status = psa_generate_key( &key_attributes, + &handshake->ecdh_psa_privkey ); + if( status != PSA_SUCCESS ) + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + + /* Export the public part of the ECDH private key from PSA + * and convert it to ECPoint format used in ClientKeyExchange. */ + status = psa_export_public_key( handshake->ecdh_psa_privkey, + own_pubkey, sizeof( own_pubkey ), + &own_pubkey_len ); + if( status != PSA_SUCCESS ) + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + + if( mbedtls_psa_tls_psa_ec_to_ecpoint( own_pubkey, + own_pubkey_len, + &own_pubkey_ecpoint, + &own_pubkey_ecpoint_len ) != 0 ) + { + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + } + + /* Copy ECPoint structure to outgoing message buffer. */ + ssl->out_msg[header_len] = (unsigned char) own_pubkey_ecpoint_len; + memcpy( ssl->out_msg + header_len + 1, + own_pubkey_ecpoint, own_pubkey_ecpoint_len ); + content_len = own_pubkey_ecpoint_len + 1; + + /* The ECDH secret is the premaster secret used for key derivation. */ + + /* Compute ECDH shared secret. */ + status = psa_raw_key_agreement( PSA_ALG_ECDH, + handshake->ecdh_psa_privkey, + handshake->ecdh_psa_peerkey, + handshake->ecdh_psa_peerkey_len, + ssl->handshake->premaster, + sizeof( ssl->handshake->premaster ), + &ssl->handshake->pmslen ); + if( status != PSA_SUCCESS ) + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + + status = psa_destroy_key( handshake->ecdh_psa_privkey ); + if( status != PSA_SUCCESS ) + return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED ); + handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT; + } + else +#endif /* MBEDTLS_USE_PSA_CRYPTO && + ( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */ +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA || + ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA ) + { + /* + * ECDH key exchange -- send client public value + */ + header_len = 4; + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + { + if( ssl->handshake->ecrs_state == ssl_ecrs_cke_ecdh_calc_secret ) + goto ecdh_calc_secret; + + mbedtls_ecdh_enable_restart( &ssl->handshake->ecdh_ctx ); + } +#endif + + ret = mbedtls_ecdh_make_public( &ssl->handshake->ecdh_ctx, + &content_len, + &ssl->out_msg[header_len], 1000, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_make_public", ret ); +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS ) + ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS; +#endif + return( ret ); + } + + MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, + MBEDTLS_DEBUG_ECDH_Q ); + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + { + ssl->handshake->ecrs_n = content_len; + ssl->handshake->ecrs_state = ssl_ecrs_cke_ecdh_calc_secret; + } + +ecdh_calc_secret: + if( ssl->handshake->ecrs_enabled ) + content_len = ssl->handshake->ecrs_n; +#endif + 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 ); +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS ) + ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS; +#endif + return( ret ); + } + + 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_SOME_PSK_ENABLED) + if( mbedtls_ssl_ciphersuite_uses_psk( ciphersuite_info ) ) + { + /* + * opaque psk_identity<0..2^16-1>; + */ + if( ssl_conf_has_static_psk( ssl->conf ) == 0 ) + { + /* We don't offer PSK suites if we don't have a PSK, + * and we check that the server's choice is among the + * ciphersuites we offered, so this should never happen. */ + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + + header_len = 4; + content_len = ssl->conf->psk_identity_len; + + if( header_len + 2 + content_len > MBEDTLS_SSL_OUT_CONTENT_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "psk identity too long or SSL buffer too short" ) ); + return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL ); + } + + ssl->out_msg[header_len++] = (unsigned char)( content_len >> 8 ); + ssl->out_msg[header_len++] = (unsigned char)( content_len ); + + memcpy( ssl->out_msg + header_len, + ssl->conf->psk_identity, + ssl->conf->psk_identity_len ); + header_len += ssl->conf->psk_identity_len; + +#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ) + { + content_len = 0; + } + else +#endif +#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ) + { +#if defined(MBEDTLS_USE_PSA_CRYPTO) + /* Opaque PSKs are currently only supported for PSK-only suites. */ + if( ssl_conf_has_static_raw_psk( ssl->conf ) == 0 ) + return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + if( ( ret = ssl_write_encrypted_pms( ssl, header_len, + &content_len, 2 ) ) != 0 ) + return( ret ); + } + else +#endif +#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ) + { +#if defined(MBEDTLS_USE_PSA_CRYPTO) + /* Opaque PSKs are currently only supported for PSK-only suites. */ + if( ssl_conf_has_static_raw_psk( ssl->conf ) == 0 ) + return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + /* + * ClientDiffieHellmanPublic public (DHM send G^X mod P) + */ + content_len = ssl->handshake->dhm_ctx.len; + + if( header_len + 2 + content_len > + MBEDTLS_SSL_OUT_CONTENT_LEN ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "psk identity or DHM size too long or SSL buffer too short" ) ); + return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL ); + } + + ssl->out_msg[header_len++] = (unsigned char)( content_len >> 8 ); + ssl->out_msg[header_len++] = (unsigned char)( content_len ); + + ret = mbedtls_dhm_make_public( &ssl->handshake->dhm_ctx, + (int) mbedtls_mpi_size( &ssl->handshake->dhm_ctx.P ), + &ssl->out_msg[header_len], content_len, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_make_public", ret ); + return( ret ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */ +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ) + { +#if defined(MBEDTLS_USE_PSA_CRYPTO) + /* Opaque PSKs are currently only supported for PSK-only suites. */ + if( ssl_conf_has_static_raw_psk( ssl->conf ) == 0 ) + return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + /* + * ClientECDiffieHellmanPublic public; + */ + ret = mbedtls_ecdh_make_public( &ssl->handshake->ecdh_ctx, + &content_len, + &ssl->out_msg[header_len], + MBEDTLS_SSL_OUT_CONTENT_LEN - header_len, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_make_public", ret ); + return( ret ); + } + + MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, + MBEDTLS_DEBUG_ECDH_Q ); + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */ + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + +#if defined(MBEDTLS_USE_PSA_CRYPTO) && \ + defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK && + ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 && + ssl_conf_has_static_raw_psk( ssl->conf ) == 0 ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, + ( "skip PMS generation for opaque PSK" ) ); + } + else +#endif /* MBEDTLS_USE_PSA_CRYPTO && + MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */ + if( ( ret = mbedtls_ssl_psk_derive_premaster( ssl, + ciphersuite_info->key_exchange ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, + "mbedtls_ssl_psk_derive_premaster", ret ); + return( ret ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */ +#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA ) + { + header_len = 4; + if( ( ret = ssl_write_encrypted_pms( ssl, header_len, + &content_len, 0 ) ) != 0 ) + return( ret ); + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */ +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE ) + { + header_len = 4; + + ret = mbedtls_ecjpake_write_round_two( &ssl->handshake->ecjpake_ctx, + ssl->out_msg + header_len, + MBEDTLS_SSL_OUT_CONTENT_LEN - header_len, + &content_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 ); + } + + ret = mbedtls_ecjpake_derive_secret( &ssl->handshake->ecjpake_ctx, + ssl->handshake->premaster, 32, &ssl->handshake->pmslen, + ssl->conf->f_rng, ssl->conf->p_rng ); + if( ret != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecjpake_derive_secret", ret ); + return( ret ); + } + } + else +#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */ + { + ((void) ciphersuite_info); + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + + ssl->out_msglen = header_len + content_len; + ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; + ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_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 client key exchange" ) ); + + return( 0 ); +} + +#if !defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED) +static int ssl_write_certificate_verify( mbedtls_ssl_context *ssl ) +{ + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) ); + + if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret ); + return( ret ); + } + + if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) ); + ssl->state++; + return( 0 ); + } + + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); +} +#else /* !MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ +static int ssl_write_certificate_verify( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + const mbedtls_ssl_ciphersuite_t *ciphersuite_info = + ssl->handshake->ciphersuite_info; + size_t n = 0, offset = 0; + unsigned char hash[48]; + unsigned char *hash_start = hash; + mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE; + size_t hashlen; + void *rs_ctx = NULL; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write certificate verify" ) ); + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled && + ssl->handshake->ecrs_state == ssl_ecrs_crt_vrfy_sign ) + { + goto sign; + } +#endif + + if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_derive_keys", ret ); + return( ret ); + } + + if( !mbedtls_ssl_ciphersuite_cert_req_allowed( ciphersuite_info ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) ); + ssl->state++; + return( 0 ); + } + + if( ssl->client_auth == 0 || mbedtls_ssl_own_cert( ssl ) == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= skip write certificate verify" ) ); + ssl->state++; + return( 0 ); + } + + if( mbedtls_ssl_own_key( ssl ) == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no private key for certificate" ) ); + return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED ); + } + + /* + * Make a signature of the handshake digests + */ +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + ssl->handshake->ecrs_state = ssl_ecrs_crt_vrfy_sign; + +sign: +#endif + + ssl->handshake->calc_verify( ssl, hash, &hashlen ); + +#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \ + defined(MBEDTLS_SSL_PROTO_TLS1_1) + if( ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3 ) + { + /* + * digitally-signed struct { + * opaque md5_hash[16]; + * opaque sha_hash[20]; + * }; + * + * md5_hash + * MD5(handshake_messages); + * + * sha_hash + * SHA(handshake_messages); + */ + md_alg = MBEDTLS_MD_NONE; + + /* + * For ECDSA, default hash is SHA-1 only + */ + if( mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_ECDSA ) ) + { + hash_start += 16; + hashlen -= 16; + md_alg = MBEDTLS_MD_SHA1; + } + } + else +#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \ + MBEDTLS_SSL_PROTO_TLS1_1 */ +#if defined(MBEDTLS_SSL_PROTO_TLS1_2) + if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 ) + { + /* + * digitally-signed struct { + * opaque handshake_messages[handshake_messages_length]; + * }; + * + * Taking shortcut here. We assume that the server always allows the + * PRF Hash function and has sent it in the allowed signature + * algorithms list received in the Certificate Request message. + * + * Until we encounter a server that does not, we will take this + * shortcut. + * + * Reason: Otherwise we should have running hashes for SHA512 and + * SHA224 in order to satisfy 'weird' needs from the server + * side. + */ + if( ssl->handshake->ciphersuite_info->mac == MBEDTLS_MD_SHA384 ) + { + md_alg = MBEDTLS_MD_SHA384; + ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA384; + } + else + { + md_alg = MBEDTLS_MD_SHA256; + ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA256; + } + ssl->out_msg[5] = mbedtls_ssl_sig_from_pk( mbedtls_ssl_own_key( ssl ) ); + + /* Info from md_alg will be used instead */ + hashlen = 0; + offset = 2; + } + else +#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); + return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); + } + +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ssl->handshake->ecrs_enabled ) + rs_ctx = &ssl->handshake->ecrs_ctx.pk; +#endif + + if( ( ret = mbedtls_pk_sign_restartable( mbedtls_ssl_own_key( ssl ), + md_alg, hash_start, hashlen, + ssl->out_msg + 6 + offset, &n, + ssl->conf->f_rng, ssl->conf->p_rng, rs_ctx ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_pk_sign", ret ); +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + if( ret == MBEDTLS_ERR_ECP_IN_PROGRESS ) + ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS; +#endif + return( ret ); + } + + ssl->out_msg[4 + offset] = (unsigned char)( n >> 8 ); + ssl->out_msg[5 + offset] = (unsigned char)( n ); + + ssl->out_msglen = 6 + n + offset; + ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE; + ssl->out_msg[0] = MBEDTLS_SSL_HS_CERTIFICATE_VERIFY; + + ssl->state++; + + if( ( ret = mbedtls_ssl_write_handshake_msg( ssl ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_write_handshake_msg", ret ); + return( ret ); + } + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write certificate verify" ) ); + + return( ret ); +} +#endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) +static int ssl_parse_new_session_ticket( mbedtls_ssl_context *ssl ) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + uint32_t lifetime; + size_t ticket_len; + unsigned char *ticket; + const unsigned char *msg; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse new session ticket" ) ); + + if( ( ret = mbedtls_ssl_read_record( ssl, 1 ) ) != 0 ) + { + MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); + return( ret ); + } + + if( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) ); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); + return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); + } + + /* + * struct { + * uint32 ticket_lifetime_hint; + * opaque ticket<0..2^16-1>; + * } NewSessionTicket; + * + * 0 . 3 ticket_lifetime_hint + * 4 . 5 ticket_len (n) + * 6 . 5+n ticket content + */ + if( ssl->in_msg[0] != MBEDTLS_SSL_HS_NEW_SESSION_TICKET || + ssl->in_hslen < 6 + mbedtls_ssl_hs_hdr_len( ssl ) ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET ); + } + + msg = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl ); + + lifetime = ( ((uint32_t) msg[0]) << 24 ) | ( msg[1] << 16 ) | + ( msg[2] << 8 ) | ( msg[3] ); + + ticket_len = ( msg[4] << 8 ) | ( msg[5] ); + + if( ticket_len + 6 + mbedtls_ssl_hs_hdr_len( ssl ) != ssl->in_hslen ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad new session ticket message" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR ); + return( MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET ); + } + + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket length: %" MBEDTLS_PRINTF_SIZET, ticket_len ) ); + + /* We're not waiting for a NewSessionTicket message any more */ + ssl->handshake->new_session_ticket = 0; + ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC; + + /* + * Zero-length ticket means the server changed his mind and doesn't want + * to send a ticket after all, so just forget it + */ + if( ticket_len == 0 ) + return( 0 ); + + if( ssl->session != NULL && ssl->session->ticket != NULL ) + { + mbedtls_platform_zeroize( ssl->session->ticket, + ssl->session->ticket_len ); + mbedtls_free( ssl->session->ticket ); + ssl->session->ticket = NULL; + ssl->session->ticket_len = 0; + } + + mbedtls_platform_zeroize( ssl->session_negotiate->ticket, + ssl->session_negotiate->ticket_len ); + mbedtls_free( ssl->session_negotiate->ticket ); + ssl->session_negotiate->ticket = NULL; + ssl->session_negotiate->ticket_len = 0; + + if( ( ticket = mbedtls_calloc( 1, ticket_len ) ) == NULL ) + { + MBEDTLS_SSL_DEBUG_MSG( 1, ( "ticket alloc failed" ) ); + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR ); + return( MBEDTLS_ERR_SSL_ALLOC_FAILED ); + } + + memcpy( ticket, msg + 6, ticket_len ); + + ssl->session_negotiate->ticket = ticket; + ssl->session_negotiate->ticket_len = ticket_len; + ssl->session_negotiate->ticket_lifetime = lifetime; + + /* + * RFC 5077 section 3.4: + * "If the client receives a session ticket from the server, then it + * discards any Session ID that was sent in the ServerHello." + */ + MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket in use, discarding session id" ) ); + ssl->session_negotiate->id_len = 0; + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse new session ticket" ) ); + + return( 0 ); +} +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + +/* + * SSL handshake -- client side -- single step + */ +int mbedtls_ssl_handshake_client_step( mbedtls_ssl_context *ssl ) +{ + int ret = 0; + + if( ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER || ssl->handshake == NULL ) + return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); + + MBEDTLS_SSL_DEBUG_MSG( 2, ( "client state: %d", ssl->state ) ); + + if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 ) + return( ret ); + +#if defined(MBEDTLS_SSL_PROTO_DTLS) + if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM && + ssl->handshake->retransmit_state == MBEDTLS_SSL_RETRANS_SENDING ) + { + if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 ) + return( ret ); + } +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + + /* Change state now, so that it is right in mbedtls_ssl_read_record(), used + * by DTLS for dropping out-of-sequence ChangeCipherSpec records */ +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + if( ssl->state == MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC && + ssl->handshake->new_session_ticket != 0 ) + { + ssl->state = MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET; + } +#endif + + switch( ssl->state ) + { + case MBEDTLS_SSL_HELLO_REQUEST: + ssl->state = MBEDTLS_SSL_CLIENT_HELLO; + break; + + /* + * ==> ClientHello + */ + case MBEDTLS_SSL_CLIENT_HELLO: + ret = ssl_write_client_hello( ssl ); + break; + + /* + * <== ServerHello + * Certificate + * ( ServerKeyExchange ) + * ( CertificateRequest ) + * ServerHelloDone + */ + case MBEDTLS_SSL_SERVER_HELLO: + ret = ssl_parse_server_hello( ssl ); + break; + + case MBEDTLS_SSL_SERVER_CERTIFICATE: + ret = mbedtls_ssl_parse_certificate( ssl ); + break; + + case MBEDTLS_SSL_SERVER_KEY_EXCHANGE: + ret = ssl_parse_server_key_exchange( ssl ); + break; + + case MBEDTLS_SSL_CERTIFICATE_REQUEST: + ret = ssl_parse_certificate_request( ssl ); + break; + + case MBEDTLS_SSL_SERVER_HELLO_DONE: + ret = ssl_parse_server_hello_done( ssl ); + break; + + /* + * ==> ( Certificate/Alert ) + * ClientKeyExchange + * ( CertificateVerify ) + * ChangeCipherSpec + * Finished + */ + case MBEDTLS_SSL_CLIENT_CERTIFICATE: + ret = mbedtls_ssl_write_certificate( ssl ); + break; + + case MBEDTLS_SSL_CLIENT_KEY_EXCHANGE: + ret = ssl_write_client_key_exchange( ssl ); + break; + + case MBEDTLS_SSL_CERTIFICATE_VERIFY: + ret = ssl_write_certificate_verify( ssl ); + break; + + case MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC: + ret = mbedtls_ssl_write_change_cipher_spec( ssl ); + break; + + case MBEDTLS_SSL_CLIENT_FINISHED: + ret = mbedtls_ssl_write_finished( ssl ); + break; + + /* + * <== ( NewSessionTicket ) + * ChangeCipherSpec + * Finished + */ +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + case MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET: + ret = ssl_parse_new_session_ticket( ssl ); + break; +#endif + + case MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC: + ret = mbedtls_ssl_parse_change_cipher_spec( ssl ); + break; + + case MBEDTLS_SSL_SERVER_FINISHED: + ret = mbedtls_ssl_parse_finished( ssl ); + break; + + case MBEDTLS_SSL_FLUSH_BUFFERS: + MBEDTLS_SSL_DEBUG_MSG( 2, ( "handshake: done" ) ); + ssl->state = MBEDTLS_SSL_HANDSHAKE_WRAPUP; + break; + + case MBEDTLS_SSL_HANDSHAKE_WRAPUP: + mbedtls_ssl_handshake_wrapup( ssl ); + break; + + default: + MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid state %d", ssl->state ) ); + return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); + } + + return( ret ); +} +#endif /* MBEDTLS_SSL_CLI_C */ |