| /* |
| * TLS 1.3 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. |
| * |
| * This file is part of mbed TLS ( https://tls.mbed.org ) |
| */ |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) |
| |
| #if defined(MBEDTLS_SSL_CLI_C) |
| |
| #include <string.h> |
| |
| #include "mbedtls/debug.h" |
| #include "mbedtls/error.h" |
| #include "mbedtls/platform.h" |
| |
| #include "ssl_misc.h" |
| #include "ecdh_misc.h" |
| #include "ssl_tls13_keys.h" |
| #include "ssl_debug_helpers_generated.h" |
| |
| /* Write extensions */ |
| |
| /* |
| * ssl_tls13_write_supported_versions_ext(): |
| * |
| * struct { |
| * ProtocolVersion versions<2..254>; |
| * } SupportedVersions; |
| */ |
| static int ssl_tls13_write_supported_versions_ext( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| unsigned char *p = buf; |
| |
| *out_len = 0; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding supported versions extension" ) ); |
| |
| /* Check if we have space to write the extension: |
| * - extension_type (2 bytes) |
| * - extension_data_length (2 bytes) |
| * - versions_length (1 byte ) |
| * - versions (2 bytes) |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 7 ); |
| |
| /* Write extension_type */ |
| MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SUPPORTED_VERSIONS, p, 0 ); |
| |
| /* Write extension_data_length */ |
| MBEDTLS_PUT_UINT16_BE( 3, p, 2 ); |
| p += 4; |
| |
| /* Length of versions */ |
| *p++ = 0x2; |
| |
| /* Write values of supported versions. |
| * |
| * They are defined by the configuration. |
| * |
| * Currently, only one version is advertised. |
| */ |
| mbedtls_ssl_write_version( ssl->conf->max_major_ver, |
| ssl->conf->max_minor_ver, |
| ssl->conf->transport, p ); |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "supported version: [%d:%d]", |
| ssl->conf->max_major_ver, |
| ssl->conf->max_minor_ver ) ); |
| |
| *out_len = 7; |
| |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_parse_supported_versions_ext( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ) |
| { |
| ((void) ssl); |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( buf, end, 2); |
| if( buf[0] != MBEDTLS_SSL_MAJOR_VERSION_3 || |
| buf[1] != MBEDTLS_SSL_MINOR_VERSION_4 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "unexpected version" ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| return( 0 ); |
| } |
| |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| |
| /* |
| * Functions for writing supported_groups extension. |
| * |
| * Stucture of supported_groups: |
| * enum { |
| * secp256r1(0x0017), secp384r1(0x0018), secp521r1(0x0019), |
| * x25519(0x001D), x448(0x001E), |
| * ffdhe2048(0x0100), ffdhe3072(0x0101), ffdhe4096(0x0102), |
| * ffdhe6144(0x0103), ffdhe8192(0x0104), |
| * ffdhe_private_use(0x01FC..0x01FF), |
| * ecdhe_private_use(0xFE00..0xFEFF), |
| * (0xFFFF) |
| * } NamedGroup; |
| * struct { |
| * NamedGroup named_group_list<2..2^16-1>; |
| * } NamedGroupList; |
| */ |
| #if defined(MBEDTLS_ECDH_C) |
| /* |
| * In versions of TLS prior to TLS 1.3, this extension was named |
| * 'elliptic_curves' and only contained elliptic curve groups. |
| */ |
| static int ssl_tls13_write_named_group_list_ecdhe( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| unsigned char *p = buf; |
| |
| *out_len = 0; |
| |
| const uint16_t *group_list = mbedtls_ssl_get_groups( ssl ); |
| |
| if( group_list == NULL ) |
| return( MBEDTLS_ERR_SSL_BAD_CONFIG ); |
| |
| for ( ; *group_list != 0; group_list++ ) |
| { |
| const mbedtls_ecp_curve_info *curve_info; |
| curve_info = mbedtls_ecp_curve_info_from_tls_id( *group_list ); |
| if( curve_info == NULL ) |
| continue; |
| |
| if( !mbedtls_ssl_tls13_named_group_is_ecdhe( *group_list ) ) |
| continue; |
| |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2); |
| MBEDTLS_PUT_UINT16_BE( *group_list, p, 0 ); |
| p += 2; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "NamedGroup: %s ( %x )", |
| curve_info->name, *group_list ) ); |
| } |
| |
| *out_len = p - buf; |
| |
| return( 0 ); |
| } |
| #else |
| static int ssl_tls13_write_named_group_list_ecdhe( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| ((void) ssl); |
| ((void) buf); |
| ((void) end); |
| *out_len = 0; |
| return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); |
| } |
| #endif /* MBEDTLS_ECDH_C */ |
| |
| static int ssl_tls13_write_named_group_list_dhe( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| ((void) ssl); |
| ((void) buf); |
| ((void) end); |
| *out_len = 0; |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "write_named_group_dhe is not implemented" ) ); |
| return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE ); |
| } |
| |
| static int ssl_tls13_write_supported_groups_ext( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| unsigned char *p = buf ; |
| unsigned char *named_group_list; /* Start of named_group_list */ |
| size_t named_group_list_len; /* Length of named_group_list */ |
| size_t output_len = 0; |
| int ret_ecdhe, ret_dhe; |
| |
| *out_len = 0; |
| |
| if( !mbedtls_ssl_conf_tls13_some_ephemeral_enabled( ssl ) ) |
| return( 0 ); |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding supported_groups extension" ) ); |
| |
| /* Check if we have space for header and length fields: |
| * - extension_type (2 bytes) |
| * - extension_data_length (2 bytes) |
| * - named_group_list_length (2 bytes) |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 ); |
| p += 6; |
| |
| named_group_list = p; |
| ret_ecdhe = ssl_tls13_write_named_group_list_ecdhe( ssl, p, end, &output_len ); |
| if( ret_ecdhe != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "ssl_tls13_write_named_group_list_ecdhe", ret_ecdhe ); |
| } |
| p += output_len; |
| |
| ret_dhe = ssl_tls13_write_named_group_list_dhe( ssl, p, end, &output_len ); |
| if( ret_dhe != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "ssl_tls13_write_named_group_list_dhe", ret_dhe ); |
| } |
| p += output_len; |
| |
| /* Both ECDHE and DHE failed. */ |
| if( ret_ecdhe != 0 && ret_dhe != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Both ECDHE and DHE groups are fail. " ) ); |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| } |
| |
| /* Length of named_group_list*/ |
| named_group_list_len = p - named_group_list; |
| if( named_group_list_len == 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "No group available." ) ); |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| } |
| |
| /* Write extension_type */ |
| MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SUPPORTED_GROUPS, buf, 0 ); |
| /* Write extension_data_length */ |
| MBEDTLS_PUT_UINT16_BE( named_group_list_len + 2, buf, 2 ); |
| /* Write length of named_group_list */ |
| MBEDTLS_PUT_UINT16_BE( named_group_list_len, buf, 4 ); |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "Supported groups extension", buf + 4, named_group_list_len + 2 ); |
| |
| *out_len = p - buf; |
| |
| ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_SUPPORTED_GROUPS; |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Functions for writing key_share extension. |
| */ |
| #if defined(MBEDTLS_ECDH_C) |
| static int ssl_tls13_generate_and_write_ecdh_key_exchange( |
| mbedtls_ssl_context *ssl, |
| uint16_t named_group, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| const mbedtls_ecp_curve_info *curve_info = |
| mbedtls_ecp_curve_info_from_tls_id( named_group ); |
| |
| if( curve_info == NULL ) |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "offer curve %s", curve_info->name ) ); |
| |
| if( ( ret = mbedtls_ecdh_setup_no_everest( &ssl->handshake->ecdh_ctx, |
| curve_info->grp_id ) ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_setup_no_everest", ret ); |
| return( ret ); |
| } |
| |
| ret = mbedtls_ecdh_tls13_make_params( &ssl->handshake->ecdh_ctx, out_len, |
| buf, end - buf, |
| ssl->conf->f_rng, ssl->conf->p_rng ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_tls13_make_params", ret ); |
| return( ret ); |
| } |
| |
| MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, |
| MBEDTLS_DEBUG_ECDH_Q ); |
| return( 0 ); |
| } |
| #endif /* MBEDTLS_ECDH_C */ |
| |
| static int ssl_tls13_get_default_group_id( mbedtls_ssl_context *ssl, |
| uint16_t *group_id ) |
| { |
| int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; |
| |
| |
| #if defined(MBEDTLS_ECDH_C) |
| const uint16_t *group_list = mbedtls_ssl_get_groups( ssl ); |
| /* Pick first available ECDHE group compatible with TLS 1.3 */ |
| if( group_list == NULL ) |
| return( MBEDTLS_ERR_SSL_BAD_CONFIG ); |
| |
| for ( ; *group_list != 0; group_list++ ) |
| { |
| const mbedtls_ecp_curve_info *curve_info; |
| curve_info = mbedtls_ecp_curve_info_from_tls_id( *group_list ); |
| if( curve_info != NULL && |
| mbedtls_ssl_tls13_named_group_is_ecdhe( *group_list ) ) |
| { |
| *group_id = *group_list; |
| return( 0 ); |
| } |
| } |
| #else |
| ((void) ssl); |
| ((void) group_id); |
| #endif /* MBEDTLS_ECDH_C */ |
| |
| /* |
| * Add DHE named groups here. |
| * Pick first available DHE group compatible with TLS 1.3 |
| */ |
| |
| return( ret ); |
| } |
| |
| /* |
| * ssl_tls13_write_key_share_ext |
| * |
| * Structure of key_share extension in ClientHello: |
| * |
| * struct { |
| * NamedGroup group; |
| * opaque key_exchange<1..2^16-1>; |
| * } KeyShareEntry; |
| * struct { |
| * KeyShareEntry client_shares<0..2^16-1>; |
| * } KeyShareClientHello; |
| */ |
| static int ssl_tls13_write_key_share_ext( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| unsigned char *p = buf; |
| unsigned char *client_shares; /* Start of client_shares */ |
| size_t client_shares_len; /* Length of client_shares */ |
| uint16_t group_id; |
| int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; |
| |
| *out_len = 0; |
| |
| if( !mbedtls_ssl_conf_tls13_some_ephemeral_enabled( ssl ) ) |
| return( 0 ); |
| |
| /* Check if we have space for header and length fields: |
| * - extension_type (2 bytes) |
| * - extension_data_length (2 bytes) |
| * - client_shares_length (2 bytes) |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 ); |
| p += 6; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello: adding key share extension" ) ); |
| |
| /* HRR could already have requested something else. */ |
| group_id = ssl->handshake->offered_group_id; |
| if( !mbedtls_ssl_tls13_named_group_is_ecdhe( group_id ) && |
| !mbedtls_ssl_tls13_named_group_is_dhe( group_id ) ) |
| { |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_get_default_group_id( ssl, |
| &group_id ) ); |
| } |
| |
| /* |
| * Dispatch to type-specific key generation function. |
| * |
| * So far, we're only supporting ECDHE. With the introduction |
| * of PQC KEMs, we'll want to have multiple branches, one per |
| * type of KEM, and dispatch to the corresponding crypto. And |
| * only one key share entry is allowed. |
| */ |
| client_shares = p; |
| #if defined(MBEDTLS_ECDH_C) |
| if( mbedtls_ssl_tls13_named_group_is_ecdhe( group_id ) ) |
| { |
| /* Pointer to group */ |
| unsigned char *group = p; |
| /* Length of key_exchange */ |
| size_t key_exchange_len; |
| |
| /* Check there is space for header of KeyShareEntry |
| * - group (2 bytes) |
| * - key_exchange_length (2 bytes) |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 ); |
| p += 4; |
| ret = ssl_tls13_generate_and_write_ecdh_key_exchange( ssl, group_id, |
| p, end, |
| &key_exchange_len ); |
| p += key_exchange_len; |
| if( ret != 0 ) |
| return( ret ); |
| |
| /* Write group */ |
| MBEDTLS_PUT_UINT16_BE( group_id, group, 0 ); |
| /* Write key_exchange_length */ |
| MBEDTLS_PUT_UINT16_BE( key_exchange_len, group, 2 ); |
| } |
| else |
| #endif /* MBEDTLS_ECDH_C */ |
| if( 0 /* other KEMs? */ ) |
| { |
| /* Do something */ |
| } |
| else |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| |
| /* Length of client_shares */ |
| client_shares_len = p - client_shares; |
| if( client_shares_len == 0) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "No key share defined." ) ); |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| } |
| /* Write extension_type */ |
| MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_KEY_SHARE, buf, 0 ); |
| /* Write extension_data_length */ |
| MBEDTLS_PUT_UINT16_BE( client_shares_len + 2, buf, 2 ); |
| /* Write client_shares_length */ |
| MBEDTLS_PUT_UINT16_BE( client_shares_len, buf, 4 ); |
| |
| /* Update offered_group_id field */ |
| ssl->handshake->offered_group_id = group_id; |
| |
| /* Output the total length of key_share extension. */ |
| *out_len = p - buf; |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, key_share extension", buf, *out_len ); |
| |
| ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_KEY_SHARE; |
| |
| cleanup: |
| |
| return( ret ); |
| } |
| |
| #if defined(MBEDTLS_ECDH_C) |
| |
| static int ssl_tls13_check_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( mbedtls_ssl_check_curve( ssl, grp_id ) != 0 ) |
| return( -1 ); |
| |
| MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx, |
| MBEDTLS_DEBUG_ECDH_QP ); |
| |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_read_public_ecdhe_share( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| size_t buf_len ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| |
| ret = mbedtls_ecdh_tls13_read_public( &ssl->handshake->ecdh_ctx, |
| buf, buf_len ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, ( "mbedtls_ecdh_tls13_read_public" ), ret ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| if( ssl_tls13_check_ecdh_params( ssl ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "ssl_tls13_check_ecdh_params() failed!" ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| return( 0 ); |
| } |
| #endif /* MBEDTLS_ECDH_C */ |
| |
| /* |
| * ssl_tls13_parse_key_share_ext() |
| * Parse key_share extension in Server Hello |
| * |
| * struct { |
| * KeyShareEntry server_share; |
| * } KeyShareServerHello; |
| * struct { |
| * NamedGroup group; |
| * opaque key_exchange<1..2^16-1>; |
| * } KeyShareEntry; |
| */ |
| static int ssl_tls13_parse_key_share_ext( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| const unsigned char *p = buf; |
| uint16_t group, offered_group; |
| |
| /* ... |
| * NamedGroup group; (2 bytes) |
| * ... |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 ); |
| group = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| p += 2; |
| |
| /* Check that the chosen group matches the one we offered. */ |
| offered_group = ssl->handshake->offered_group_id; |
| if( offered_group != group ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, |
| ( "Invalid server key share, our group %u, their group %u", |
| (unsigned) offered_group, (unsigned) group ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE, |
| MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| return( MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| } |
| |
| #if defined(MBEDTLS_ECDH_C) |
| if( mbedtls_ssl_tls13_named_group_is_ecdhe( group ) ) |
| { |
| /* Complete ECDHE key agreement */ |
| ret = ssl_tls13_read_public_ecdhe_share( ssl, p, end - p ); |
| if( ret != 0 ) |
| return( ret ); |
| } |
| else |
| #endif /* MBEDTLS_ECDH_C */ |
| if( 0 /* other KEMs? */ ) |
| { |
| /* Do something */ |
| } |
| else |
| return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); |
| |
| ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_KEY_SHARE; |
| return( ret ); |
| } |
| |
| #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ |
| |
| /* Write cipher_suites |
| * CipherSuite cipher_suites<2..2^16-2>; |
| */ |
| static int ssl_tls13_write_client_hello_cipher_suites( |
| mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| unsigned char *p = buf; |
| const int *ciphersuite_list; |
| unsigned char *cipher_suites; /* Start of the cipher_suites list */ |
| size_t cipher_suites_len; |
| |
| *out_len = 0 ; |
| |
| /* |
| * Ciphersuite list |
| * |
| * This is a list of the symmetric cipher options supported by |
| * the client, specifically the record protection algorithm |
| * ( including secret key length ) and a hash to be used with |
| * HKDF, in descending order of client preference. |
| */ |
| ciphersuite_list = ssl->conf->ciphersuite_list; |
| |
| /* Check there is space for the cipher suite list length (2 bytes). */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); |
| p += 2; |
| |
| /* Write cipher_suites */ |
| cipher_suites = p; |
| for ( size_t i = 0; ciphersuite_list[i] != 0; i++ ) |
| { |
| int cipher_suite = ciphersuite_list[i]; |
| const mbedtls_ssl_ciphersuite_t *ciphersuite_info; |
| |
| ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( cipher_suite ); |
| if( ciphersuite_info == NULL ) |
| continue; |
| if( !( MBEDTLS_SSL_MINOR_VERSION_4 >= ciphersuite_info->min_minor_ver && |
| MBEDTLS_SSL_MINOR_VERSION_4 <= ciphersuite_info->max_minor_ver ) ) |
| continue; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, add ciphersuite: %04x, %s", |
| (unsigned int) cipher_suite, |
| ciphersuite_info->name ) ); |
| |
| /* Check there is space for the cipher suite identifier (2 bytes). */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); |
| MBEDTLS_PUT_UINT16_BE( cipher_suite, p, 0 ); |
| p += 2; |
| } |
| |
| /* Write the cipher_suites length in number of bytes */ |
| cipher_suites_len = p - cipher_suites; |
| MBEDTLS_PUT_UINT16_BE( cipher_suites_len, buf, 0 ); |
| MBEDTLS_SSL_DEBUG_MSG( 3, |
| ( "client hello, got %" MBEDTLS_PRINTF_SIZET " cipher suites", |
| cipher_suites_len/2 ) ); |
| |
| /* Output the total length of cipher_suites field. */ |
| *out_len = p - buf; |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Structure of ClientHello message: |
| * |
| * struct { |
| * ProtocolVersion legacy_version = 0x0303; // TLS v1.2 |
| * Random random; |
| * opaque legacy_session_id<0..32>; |
| * CipherSuite cipher_suites<2..2^16-2>; |
| * opaque legacy_compression_methods<1..2^8-1>; |
| * Extension extensions<8..2^16-1>; |
| * } ClientHello; |
| */ |
| static int ssl_tls13_write_client_hello_body( mbedtls_ssl_context *ssl, |
| unsigned char *buf, |
| unsigned char *end, |
| size_t *out_len ) |
| { |
| |
| int ret; |
| unsigned char *p_extensions_len; /* Pointer to extensions length */ |
| size_t output_len; /* Length of buffer used by function */ |
| size_t extensions_len; /* Length of the list of extensions*/ |
| |
| /* Buffer management */ |
| unsigned char *p = buf; |
| |
| *out_len = 0; |
| |
| /* No validation needed here. It has been done by ssl_conf_check() */ |
| ssl->major_ver = ssl->conf->min_major_ver; |
| ssl->minor_ver = ssl->conf->min_minor_ver; |
| |
| /* |
| * Write legacy_version |
| * ProtocolVersion legacy_version = 0x0303; // TLS v1.2 |
| * |
| * For TLS 1.3 we use the legacy version number {0x03, 0x03} |
| * instead of the true version number. |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); |
| MBEDTLS_PUT_UINT16_BE( 0x0303, p, 0 ); |
| p += 2; |
| |
| /* Write the random bytes ( random ).*/ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, MBEDTLS_CLIENT_HELLO_RANDOM_LEN ); |
| memcpy( p, ssl->handshake->randbytes, MBEDTLS_CLIENT_HELLO_RANDOM_LEN ); |
| MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, random bytes", |
| p, MBEDTLS_CLIENT_HELLO_RANDOM_LEN ); |
| p += MBEDTLS_CLIENT_HELLO_RANDOM_LEN; |
| |
| /* |
| * Write legacy_session_id |
| * |
| * Versions of TLS before TLS 1.3 supported a "session resumption" feature |
| * which has been merged with pre-shared keys in this version. A client |
| * which has a cached session ID set by a pre-TLS 1.3 server SHOULD set |
| * this field to that value. In compatibility mode, this field MUST be |
| * non-empty, so a client not offering a pre-TLS 1.3 session MUST generate |
| * a new 32-byte value. This value need not be random but SHOULD be |
| * unpredictable to avoid implementations fixating on a specific value |
| * ( also known as ossification ). Otherwise, it MUST be set as a zero-length |
| * vector ( i.e., a zero-valued single byte length field ). |
| */ |
| #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE) |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, ssl->session_negotiate->id_len + 1 ); |
| *p++ = (unsigned char)ssl->session_negotiate->id_len; |
| memcpy( p, ssl->session_negotiate->id, ssl->session_negotiate->id_len ); |
| p += ssl->session_negotiate->id_len; |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "session id", ssl->session_negotiate->id, |
| ssl->session_negotiate->id_len ); |
| #else |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 1 ); |
| *p++ = 0; /* session id length set to zero */ |
| #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */ |
| |
| /* Write cipher_suites */ |
| ret = ssl_tls13_write_client_hello_cipher_suites( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| |
| /* Write legacy_compression_methods |
| * |
| * For every TLS 1.3 ClientHello, this vector MUST contain exactly |
| * one byte set to zero, which corresponds to the 'null' compression |
| * method in prior versions of TLS. |
| */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); |
| *p++ = 1; |
| *p++ = MBEDTLS_SSL_COMPRESS_NULL; |
| |
| /* Write extensions */ |
| |
| /* Keeping track of the included extensions */ |
| ssl->handshake->extensions_present = MBEDTLS_SSL_EXT_NONE; |
| |
| /* First write extensions, then the total length */ |
| MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 ); |
| p_extensions_len = p; |
| p += 2; |
| |
| /* Write supported_versions extension |
| * |
| * Supported Versions Extension is mandatory with TLS 1.3. |
| */ |
| ret = ssl_tls13_write_supported_versions_ext( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| /* Write supported_groups extension |
| * |
| * It is REQUIRED for ECDHE cipher_suites. |
| */ |
| ret = ssl_tls13_write_supported_groups_ext( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| |
| /* Write key_share extension |
| * |
| * We need to send the key shares under three conditions: |
| * 1) A certificate-based ciphersuite is being offered. In this case |
| * supported_groups and supported_signature extensions have been |
| * successfully added. |
| * 2) A PSK-based ciphersuite with ECDHE is offered. In this case the |
| * psk_key_exchange_modes has been added as the last extension. |
| * 3) Or, in case all ciphers are supported ( which includes #1 and #2 |
| * from above ) |
| */ |
| ret = ssl_tls13_write_key_share_ext( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| |
| /* Write signature_algorithms extension |
| * |
| * It is REQUIRED for certificate authenticated cipher_suites. |
| */ |
| ret = mbedtls_ssl_tls13_write_sig_alg_ext( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| |
| #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ |
| |
| #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) |
| /* Write server name extension */ |
| ret = mbedtls_ssl_write_hostname_ext( ssl, p, end, &output_len ); |
| if( ret != 0 ) |
| return( ret ); |
| p += output_len; |
| #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ |
| |
| /* Add more extensions here */ |
| |
| /* Write the length of the list of extensions. */ |
| extensions_len = p - p_extensions_len - 2; |
| MBEDTLS_PUT_UINT16_BE( extensions_len, p_extensions_len, 0 ); |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %" MBEDTLS_PRINTF_SIZET , |
| extensions_len ) ); |
| MBEDTLS_SSL_DEBUG_BUF( 3, "client hello extensions", p_extensions_len, extensions_len ); |
| |
| *out_len = p - buf; |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_finalize_client_hello( mbedtls_ssl_context *ssl ) |
| { |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_SERVER_HELLO ); |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_prepare_client_hello( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| if( ssl->conf->f_rng == NULL ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "no RNG provided" ) ); |
| return( MBEDTLS_ERR_SSL_NO_RNG ); |
| } |
| |
| if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, |
| ssl->handshake->randbytes, |
| MBEDTLS_CLIENT_HELLO_RANDOM_LEN ) ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "f_rng", ret ); |
| return( ret ); |
| } |
| |
| #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE) |
| /* |
| * Create a session identifier for the purpose of middlebox compatibility |
| * only if one has not been created already. |
| */ |
| if( ssl->session_negotiate->id_len == 0 ) |
| { |
| /* Creating a session id with 32 byte length */ |
| if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, |
| ssl->session_negotiate->id, 32 ) ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "creating session id failed", ret ); |
| return( ret ); |
| } |
| ssl->session_negotiate->id_len = 32; |
| } |
| #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */ |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Write ClientHello handshake message. |
| * Handler for MBEDTLS_SSL_CLIENT_HELLO |
| */ |
| static int ssl_tls13_write_client_hello( mbedtls_ssl_context *ssl ) |
| { |
| int ret = 0; |
| unsigned char *buf; |
| size_t buf_len, msg_len; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> write client hello" ) ); |
| |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_prepare_client_hello( ssl ) ); |
| |
| MBEDTLS_SSL_PROC_CHK( mbedtls_ssl_tls13_start_handshake_msg( |
| ssl, MBEDTLS_SSL_HS_CLIENT_HELLO, |
| &buf, &buf_len ) ); |
| |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_write_client_hello_body( ssl, buf, |
| buf + buf_len, |
| &msg_len ) ); |
| |
| mbedtls_ssl_tls13_add_hs_hdr_to_checksum( ssl, |
| MBEDTLS_SSL_HS_CLIENT_HELLO, |
| msg_len ); |
| ssl->handshake->update_checksum( ssl, buf, msg_len ); |
| |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_finalize_client_hello( ssl ) ); |
| MBEDTLS_SSL_PROC_CHK( mbedtls_ssl_tls13_finish_handshake_msg( ssl, |
| buf_len, |
| msg_len ) ); |
| |
| cleanup: |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= write client hello" ) ); |
| return ret; |
| } |
| |
| /* |
| * Functions for parsing and processing Server Hello |
| */ |
| /* Returns a negative value on failure, and otherwise |
| * - SSL_SERVER_HELLO_COORDINATE_HELLO or |
| * - SSL_SERVER_HELLO_COORDINATE_HRR |
| * to indicate which message is expected and to be parsed next. */ |
| #define SSL_SERVER_HELLO_COORDINATE_HELLO 0 |
| #define SSL_SERVER_HELLO_COORDINATE_HRR 1 |
| static int ssl_server_hello_is_hrr( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ) |
| { |
| static const unsigned char magic_hrr_string[MBEDTLS_SERVER_HELLO_RANDOM_LEN] = |
| { 0xCF, 0x21, 0xAD, 0x74, 0xE5, 0x9A, 0x61, 0x11, |
| 0xBE, 0x1D, 0x8C, 0x02, 0x1E, 0x65, 0xB8, 0x91, |
| 0xC2, 0xA2, 0x11, 0x16, 0x7A, 0xBB, 0x8C, 0x5E, |
| 0x07, 0x9E, 0x09, 0xE2, 0xC8, 0xA8, 0x33 ,0x9C }; |
| |
| /* Check whether this message is a HelloRetryRequest ( HRR ) message. |
| * |
| * Server Hello and HRR are only distinguished by Random set to the |
| * special value of the SHA-256 of "HelloRetryRequest". |
| * |
| * struct { |
| * ProtocolVersion legacy_version = 0x0303; |
| * Random random; |
| * opaque legacy_session_id_echo<0..32>; |
| * CipherSuite cipher_suite; |
| * uint8 legacy_compression_method = 0; |
| * Extension extensions<6..2^16-1>; |
| * } ServerHello; |
| * |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( buf, end, 2 + sizeof( magic_hrr_string ) ); |
| |
| if( memcmp( buf + 2, magic_hrr_string, sizeof( magic_hrr_string ) ) == 0 ) |
| { |
| return( SSL_SERVER_HELLO_COORDINATE_HRR ); |
| } |
| |
| return( SSL_SERVER_HELLO_COORDINATE_HELLO ); |
| } |
| |
| /* Fetch and preprocess |
| * Returns a negative value on failure, and otherwise |
| * - SSL_SERVER_HELLO_COORDINATE_HELLO or |
| * - SSL_SERVER_HELLO_COORDINATE_HRR |
| */ |
| static int ssl_tls13_server_hello_coordinate( mbedtls_ssl_context *ssl, |
| unsigned char **buf, |
| size_t *buf_len ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| |
| MBEDTLS_SSL_PROC_CHK( mbedtls_ssl_read_record( ssl, 0 ) ); |
| |
| if( ( ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE ) || |
| ( ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_HELLO ) ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "unexpected message" ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE, |
| MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); |
| return( MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE ); |
| } |
| |
| *buf = ssl->in_msg + 4; |
| *buf_len = ssl->in_hslen - 4; |
| |
| ret = ssl_server_hello_is_hrr( ssl, *buf, *buf + *buf_len ); |
| switch( ret ) |
| { |
| case SSL_SERVER_HELLO_COORDINATE_HELLO: |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "received ServerHello message" ) ); |
| break; |
| case SSL_SERVER_HELLO_COORDINATE_HRR: |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "received HelloRetryRequest message" ) ); |
| break; |
| } |
| |
| cleanup: |
| |
| return( ret ); |
| } |
| |
| static int ssl_tls13_check_server_hello_session_id_echo( mbedtls_ssl_context *ssl, |
| const unsigned char **buf, |
| const unsigned char *end ) |
| { |
| const unsigned char *p = *buf; |
| size_t legacy_session_id_echo_len; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 1 ); |
| legacy_session_id_echo_len = *p++ ; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, legacy_session_id_echo_len ); |
| |
| /* legacy_session_id_echo */ |
| if( ssl->session_negotiate->id_len != legacy_session_id_echo_len || |
| memcmp( ssl->session_negotiate->id, p , legacy_session_id_echo_len ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_BUF( 3, "Expected Session ID", |
| ssl->session_negotiate->id, |
| ssl->session_negotiate->id_len ); |
| MBEDTLS_SSL_DEBUG_BUF( 3, "Received Session ID", p, |
| legacy_session_id_echo_len ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER); |
| |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| p += legacy_session_id_echo_len; |
| *buf = p; |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "Session ID", ssl->session_negotiate->id, |
| ssl->session_negotiate->id_len ); |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_cipher_suite_is_offered( mbedtls_ssl_context *ssl, |
| int cipher_suite ) |
| { |
| const int *ciphersuite_list = ssl->conf->ciphersuite_list; |
| |
| /* Check whether we have offered this ciphersuite */ |
| for ( size_t i = 0; ciphersuite_list[i] != 0; i++ ) |
| { |
| if( ciphersuite_list[i] == cipher_suite ) |
| { |
| return( 1 ); |
| } |
| } |
| return( 0 ); |
| } |
| |
| /* Parse ServerHello message and configure context |
| * |
| * struct { |
| * ProtocolVersion legacy_version = 0x0303; // TLS 1.2 |
| * Random random; |
| * opaque legacy_session_id_echo<0..32>; |
| * CipherSuite cipher_suite; |
| * uint8 legacy_compression_method = 0; |
| * Extension extensions<6..2^16-1>; |
| * } ServerHello; |
| */ |
| static int ssl_tls13_parse_server_hello( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| const unsigned char *p = buf; |
| size_t extensions_len; |
| const unsigned char *extensions_end; |
| uint16_t cipher_suite; |
| const mbedtls_ssl_ciphersuite_t *ciphersuite_info; |
| |
| /* |
| * Check there is space for minimal fields |
| * |
| * - legacy_version ( 2 bytes) |
| * - random (MBEDTLS_SERVER_HELLO_RANDOM_LEN bytes) |
| * - legacy_session_id_echo ( 1 byte ), minimum size |
| * - cipher_suite ( 2 bytes) |
| * - legacy_compression_method ( 1 byte ) |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, MBEDTLS_SERVER_HELLO_RANDOM_LEN + 6 ); |
| |
| MBEDTLS_SSL_DEBUG_BUF( 4, "server hello", p, end - p ); |
| MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, version", p, 2 ); |
| |
| /* ... |
| * ProtocolVersion legacy_version = 0x0303; // TLS 1.2 |
| * ... |
| * with ProtocolVersion defined as: |
| * uint16 ProtocolVersion; |
| */ |
| if( !( p[0] == MBEDTLS_SSL_MAJOR_VERSION_3 && |
| p[1] == MBEDTLS_SSL_MINOR_VERSION_3 ) ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Unsupported version of TLS." ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION, |
| MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION ); |
| return( MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION ); |
| } |
| p += 2; |
| |
| /* ... |
| * Random random; |
| * ... |
| * with Random defined as: |
| * opaque Random[MBEDTLS_SERVER_HELLO_RANDOM_LEN]; |
| */ |
| memcpy( &ssl->handshake->randbytes[MBEDTLS_CLIENT_HELLO_RANDOM_LEN], p, |
| MBEDTLS_SERVER_HELLO_RANDOM_LEN ); |
| MBEDTLS_SSL_DEBUG_BUF( 3, "server hello, random bytes", |
| p, MBEDTLS_SERVER_HELLO_RANDOM_LEN ); |
| p += MBEDTLS_SERVER_HELLO_RANDOM_LEN; |
| |
| /* ... |
| * opaque legacy_session_id_echo<0..32>; |
| * ... |
| */ |
| if( ssl_tls13_check_server_hello_session_id_echo( ssl, &p, end ) != 0 ) |
| { |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| /* ... |
| * CipherSuite cipher_suite; |
| * ... |
| * with CipherSuite defined as: |
| * uint8 CipherSuite[2]; |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 ); |
| cipher_suite = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| p += 2; |
| |
| |
| /* |
| * Check whether this ciphersuite is supported and offered. |
| * Via the force_ciphersuite version we may have instructed the client |
| * to use a different ciphersuite. |
| */ |
| ciphersuite_info = mbedtls_ssl_ciphersuite_from_id( cipher_suite ); |
| if( ciphersuite_info == NULL || |
| ssl_tls13_cipher_suite_is_offered( ssl, cipher_suite ) == 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "ciphersuite(%04x) not found or not offered", |
| cipher_suite ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| |
| |
| /* Configure ciphersuites */ |
| mbedtls_ssl_optimize_checksum( ssl, ciphersuite_info ); |
| |
| ssl->handshake->ciphersuite_info = ciphersuite_info; |
| ssl->session_negotiate->ciphersuite = cipher_suite; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, chosen ciphersuite: ( %04x ) - %s", |
| cipher_suite, ciphersuite_info->name ) ); |
| |
| #if defined(MBEDTLS_HAVE_TIME) |
| ssl->session_negotiate->start = time( NULL ); |
| #endif /* MBEDTLS_HAVE_TIME */ |
| |
| /* ... |
| * uint8 legacy_compression_method = 0; |
| * ... |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 1 ); |
| if( p[0] != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad legacy compression method" ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER, |
| MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER ); |
| } |
| p++; |
| |
| /* ... |
| * Extension extensions<6..2^16-1>; |
| * ... |
| * struct { |
| * ExtensionType extension_type; (2 bytes) |
| * opaque extension_data<0..2^16-1>; |
| * } Extension; |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 ); |
| extensions_len = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| p += 2; |
| |
| /* Check extensions do not go beyond the buffer of data. */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, extensions_len ); |
| extensions_end = p + extensions_len; |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "server hello extensions", p, extensions_len ); |
| |
| while( p < extensions_end ) |
| { |
| unsigned int extension_type; |
| size_t extension_data_len; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, extensions_end, 4 ); |
| extension_type = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| extension_data_len = MBEDTLS_GET_UINT16_BE( p, 2 ); |
| p += 4; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, extensions_end, extension_data_len ); |
| |
| switch( extension_type ) |
| { |
| case MBEDTLS_TLS_EXT_SUPPORTED_VERSIONS: |
| MBEDTLS_SSL_DEBUG_MSG( 3, |
| ( "found supported_versions extension" ) ); |
| |
| ret = ssl_tls13_parse_supported_versions_ext( ssl, |
| p, |
| p + extension_data_len ); |
| if( ret != 0 ) |
| return( ret ); |
| break; |
| |
| case MBEDTLS_TLS_EXT_PRE_SHARED_KEY: |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "found pre_shared_key extension." ) ); |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "pre_shared_key:Not supported yet" ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( |
| MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT, |
| MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| return( MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| case MBEDTLS_TLS_EXT_KEY_SHARE: |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "found key_shares extension" ) ); |
| if( ( ret = ssl_tls13_parse_key_share_ext( ssl, |
| p, p + extension_data_len ) ) != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, |
| "ssl_tls13_parse_key_share_ext", |
| ret ); |
| return( ret ); |
| } |
| break; |
| #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ |
| |
| default: |
| MBEDTLS_SSL_DEBUG_MSG( |
| 3, |
| ( "unknown extension found: %u ( ignoring )", |
| extension_type ) ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( |
| MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT, |
| MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| return( MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| } |
| |
| p += extension_data_len; |
| } |
| |
| return( 0 ); |
| } |
| |
| static int ssl_tls13_finalize_server_hello( mbedtls_ssl_context *ssl ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| mbedtls_ssl_key_set traffic_keys; |
| mbedtls_ssl_transform *transform_handshake = NULL; |
| mbedtls_ssl_handshake_params *handshake = ssl->handshake; |
| |
| /* Determine the key exchange mode: |
| * 1) If both the pre_shared_key and key_share extensions were received |
| * then the key exchange mode is PSK with EPHEMERAL. |
| * 2) If only the pre_shared_key extension was received then the key |
| * exchange mode is PSK-only. |
| * 3) If only the key_share extension was received then the key |
| * exchange mode is EPHEMERAL-only. |
| */ |
| switch( handshake->extensions_present & |
| ( MBEDTLS_SSL_EXT_PRE_SHARED_KEY | MBEDTLS_SSL_EXT_KEY_SHARE ) ) |
| { |
| /* Only the pre_shared_key extension was received */ |
| case MBEDTLS_SSL_EXT_PRE_SHARED_KEY: |
| handshake->tls13_kex_modes = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK; |
| break; |
| |
| /* Only the key_share extension was received */ |
| case MBEDTLS_SSL_EXT_KEY_SHARE: |
| handshake->tls13_kex_modes = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL; |
| break; |
| |
| /* Both the pre_shared_key and key_share extensions were received */ |
| case ( MBEDTLS_SSL_EXT_PRE_SHARED_KEY | MBEDTLS_SSL_EXT_KEY_SHARE ): |
| handshake->tls13_kex_modes = MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL; |
| break; |
| |
| /* Neither pre_shared_key nor key_share extension was received */ |
| default: |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Unknown key exchange." ) ); |
| ret = MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; |
| goto cleanup; |
| } |
| |
| /* Start the TLS 1.3 key schedule: Set the PSK and derive early secret. |
| * |
| * TODO: We don't have to do this in case we offered 0-RTT and the |
| * server accepted it. In this case, we could skip generating |
| * the early secret. */ |
| ret = mbedtls_ssl_tls13_key_schedule_stage_early( ssl ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_tls13_key_schedule_stage_early_data", |
| ret ); |
| goto cleanup; |
| } |
| |
| /* Compute handshake secret */ |
| ret = mbedtls_ssl_tls13_key_schedule_stage_handshake( ssl ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_tls13_derive_master_secret", ret ); |
| goto cleanup; |
| } |
| |
| /* Next evolution in key schedule: Establish handshake secret and |
| * key material. */ |
| ret = mbedtls_ssl_tls13_generate_handshake_keys( ssl, &traffic_keys ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_tls13_generate_handshake_keys", |
| ret ); |
| goto cleanup; |
| } |
| |
| transform_handshake = mbedtls_calloc( 1, sizeof( mbedtls_ssl_transform ) ); |
| if( transform_handshake == NULL ) |
| { |
| ret = MBEDTLS_ERR_SSL_ALLOC_FAILED; |
| goto cleanup; |
| } |
| |
| ret = mbedtls_ssl_tls13_populate_transform( transform_handshake, |
| ssl->conf->endpoint, |
| ssl->session_negotiate->ciphersuite, |
| &traffic_keys, |
| ssl ); |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_tls13_populate_transform", ret ); |
| goto cleanup; |
| } |
| |
| handshake->transform_handshake = transform_handshake; |
| mbedtls_ssl_set_inbound_transform( ssl, transform_handshake ); |
| |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Switch to handshake keys for inbound traffic" ) ); |
| ssl->session_in = ssl->session_negotiate; |
| |
| /* |
| * State machine update |
| */ |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_ENCRYPTED_EXTENSIONS ); |
| |
| cleanup: |
| |
| mbedtls_platform_zeroize( &traffic_keys, sizeof( traffic_keys ) ); |
| if( ret != 0 ) |
| { |
| mbedtls_free( transform_handshake ); |
| |
| MBEDTLS_SSL_PEND_FATAL_ALERT( |
| MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE, |
| MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| } |
| return( ret ); |
| } |
| |
| /* |
| * Wait and parse ServerHello handshake message. |
| * Handler for MBEDTLS_SSL_SERVER_HELLO |
| */ |
| static int ssl_tls13_process_server_hello( mbedtls_ssl_context *ssl ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char *buf; |
| size_t buf_len; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> %s", __func__ ) ); |
| |
| /* Coordination step |
| * - Fetch record |
| * - Make sure it's either a ServerHello or a HRR. |
| * - Switch processing routine in case of HRR |
| */ |
| ssl->major_ver = MBEDTLS_SSL_MAJOR_VERSION_3; |
| ssl->handshake->extensions_present = MBEDTLS_SSL_EXT_NONE; |
| |
| ret = ssl_tls13_server_hello_coordinate( ssl, &buf, &buf_len ); |
| /* Parsing step |
| * We know what message to expect by now and call |
| * the respective parsing function. |
| */ |
| if( ret == SSL_SERVER_HELLO_COORDINATE_HELLO ) |
| { |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_parse_server_hello( ssl, buf, |
| buf + buf_len ) ); |
| |
| mbedtls_ssl_tls13_add_hs_msg_to_checksum( ssl, |
| MBEDTLS_SSL_HS_SERVER_HELLO, |
| buf, buf_len ); |
| |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_finalize_server_hello( ssl ) ); |
| } |
| else if( ret == SSL_SERVER_HELLO_COORDINATE_HRR ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "HRR not supported" ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE , |
| MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| ret = MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; |
| } |
| |
| cleanup: |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= %s", __func__ ) ); |
| return( ret ); |
| } |
| |
| /* |
| * |
| * EncryptedExtensions message |
| * |
| * The EncryptedExtensions message contains any extensions which |
| * should be protected, i.e., any which are not needed to establish |
| * the cryptographic context. |
| */ |
| |
| /* |
| * Overview |
| */ |
| |
| /* Main entry point; orchestrates the other functions */ |
| static int ssl_tls13_process_encrypted_extensions( mbedtls_ssl_context *ssl ); |
| |
| static int ssl_tls13_parse_encrypted_extensions( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ); |
| static int ssl_tls13_postprocess_encrypted_extensions( mbedtls_ssl_context *ssl ); |
| |
| /* |
| * Handler for MBEDTLS_SSL_ENCRYPTED_EXTENSIONS |
| */ |
| static int ssl_tls13_process_encrypted_extensions( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| unsigned char *buf; |
| size_t buf_len; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse encrypted extensions" ) ); |
| |
| MBEDTLS_SSL_PROC_CHK( mbedtls_ssl_tls13_fetch_handshake_msg( ssl, |
| MBEDTLS_SSL_HS_ENCRYPTED_EXTENSIONS, |
| &buf, &buf_len ) ); |
| |
| /* Process the message contents */ |
| MBEDTLS_SSL_PROC_CHK( |
| ssl_tls13_parse_encrypted_extensions( ssl, buf, buf + buf_len ) ); |
| |
| mbedtls_ssl_tls13_add_hs_msg_to_checksum( |
| ssl, MBEDTLS_SSL_HS_ENCRYPTED_EXTENSIONS, buf, buf_len ); |
| |
| MBEDTLS_SSL_PROC_CHK( ssl_tls13_postprocess_encrypted_extensions( ssl ) ); |
| |
| cleanup: |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse encrypted extensions" ) ); |
| return( ret ); |
| |
| } |
| |
| /* Parse EncryptedExtensions message |
| * struct { |
| * Extension extensions<0..2^16-1>; |
| * } EncryptedExtensions; |
| */ |
| static int ssl_tls13_parse_encrypted_extensions( mbedtls_ssl_context *ssl, |
| const unsigned char *buf, |
| const unsigned char *end ) |
| { |
| int ret = 0; |
| size_t extensions_len; |
| const unsigned char *p = buf; |
| const unsigned char *extensions_end; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 ); |
| extensions_len = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| p += 2; |
| |
| MBEDTLS_SSL_DEBUG_BUF( 3, "encrypted extensions", p, extensions_len ); |
| extensions_end = p + extensions_len; |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, extensions_len ); |
| |
| while( p < extensions_end ) |
| { |
| unsigned int extension_type; |
| size_t extension_data_len; |
| |
| /* |
| * struct { |
| * ExtensionType extension_type; (2 bytes) |
| * opaque extension_data<0..2^16-1>; |
| * } Extension; |
| */ |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, extensions_end, 4 ); |
| extension_type = MBEDTLS_GET_UINT16_BE( p, 0 ); |
| extension_data_len = MBEDTLS_GET_UINT16_BE( p, 2 ); |
| p += 4; |
| |
| MBEDTLS_SSL_CHK_BUF_READ_PTR( p, extensions_end, extension_data_len ); |
| |
| /* The client MUST check EncryptedExtensions for the |
| * presence of any forbidden extensions and if any are found MUST abort |
| * the handshake with an "unsupported_extension" alert. |
| */ |
| switch( extension_type ) |
| { |
| |
| case MBEDTLS_TLS_EXT_SUPPORTED_GROUPS: |
| MBEDTLS_SSL_DEBUG_MSG( 3, ( "found extensions supported groups" ) ); |
| break; |
| |
| default: |
| MBEDTLS_SSL_DEBUG_MSG( |
| 3, ( "unsupported extension found: %u ", extension_type) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( |
| MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT, |
| MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| return ( MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION ); |
| } |
| |
| p += extension_data_len; |
| } |
| |
| /* Check that we consumed all the message. */ |
| if( p != end ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "EncryptedExtension lengths misaligned" ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR, |
| MBEDTLS_ERR_SSL_DECODE_ERROR ); |
| return( MBEDTLS_ERR_SSL_DECODE_ERROR ); |
| } |
| |
| return( ret ); |
| } |
| |
| static int ssl_tls13_postprocess_encrypted_extensions( mbedtls_ssl_context *ssl ) |
| { |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| if( mbedtls_ssl_tls13_some_psk_enabled( ssl ) ) |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_SERVER_FINISHED ); |
| else |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CERTIFICATE_REQUEST ); |
| #else |
| ((void) ssl); |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_SERVER_FINISHED ); |
| #endif |
| return( 0 ); |
| } |
| |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| /* |
| * Handler for MBEDTLS_SSL_CERTIFICATE_REQUEST |
| */ |
| static int ssl_tls13_process_certificate_request( mbedtls_ssl_context *ssl ) |
| { |
| int ret = mbedtls_ssl_read_record( ssl, 0 ); |
| |
| if( ret != 0 ) |
| { |
| MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_read_record", ret ); |
| return( ret ); |
| } |
| |
| if( ( ssl->in_msgtype == MBEDTLS_SSL_MSG_HANDSHAKE ) && |
| ( ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE_REQUEST ) ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "CertificateRequest not supported" ) ); |
| MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE, |
| MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| return( MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE ); |
| } |
| |
| ssl->keep_current_message = 1; |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_SERVER_CERTIFICATE ); |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Handler for MBEDTLS_SSL_SERVER_CERTIFICATE |
| */ |
| static int ssl_tls13_process_server_certificate( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| ret = mbedtls_ssl_tls13_process_certificate( ssl ); |
| if( ret != 0 ) |
| return( ret ); |
| |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CERTIFICATE_VERIFY ); |
| return( 0 ); |
| } |
| |
| /* |
| * Handler for MBEDTLS_SSL_CERTIFICATE_VERIFY |
| */ |
| static int ssl_tls13_process_certificate_verify( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| ret = mbedtls_ssl_tls13_process_certificate_verify( ssl ); |
| if( ret != 0 ) |
| return( ret ); |
| |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_SERVER_FINISHED ); |
| return( 0 ); |
| } |
| #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ |
| |
| /* |
| * Handler for MBEDTLS_SSL_SERVER_FINISHED |
| */ |
| static int ssl_tls13_process_server_finished( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| ret = mbedtls_ssl_tls13_process_finished_message( ssl ); |
| if( ret != 0 ) |
| return( ret ); |
| |
| #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE) |
| mbedtls_ssl_handshake_set_state( |
| ssl, |
| MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED ); |
| #else |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CLIENT_FINISHED ); |
| #endif |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Handler for MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED |
| */ |
| #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE) |
| static int ssl_tls13_write_change_cipher_spec( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| ret = mbedtls_ssl_tls13_write_change_cipher_spec( ssl ); |
| if( ret != 0 ) |
| return( ret ); |
| |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CLIENT_FINISHED ); |
| |
| return( 0 ); |
| } |
| #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */ |
| |
| /* |
| * Handler for MBEDTLS_SSL_CLIENT_FINISHED |
| */ |
| static int ssl_tls13_write_client_finished( mbedtls_ssl_context *ssl ) |
| { |
| int ret; |
| |
| mbedtls_ssl_set_outbound_transform( ssl, ssl->handshake->transform_handshake ); |
| |
| ret = mbedtls_ssl_tls13_write_finished_message( ssl ); |
| if( ret != 0 ) |
| return( ret ); |
| |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_FLUSH_BUFFERS ); |
| return( 0 ); |
| } |
| |
| /* |
| * Handler for MBEDTLS_SSL_FLUSH_BUFFERS |
| */ |
| static int ssl_tls13_flush_buffers( mbedtls_ssl_context *ssl ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "handshake: done" ) ); |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_HANDSHAKE_WRAPUP ); |
| return( 0 ); |
| } |
| |
| /* |
| * Handler for MBEDTLS_SSL_HANDSHAKE_WRAPUP |
| */ |
| static int ssl_tls13_handshake_wrapup( mbedtls_ssl_context *ssl ) |
| { |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Switch to application keys for inbound traffic" ) ); |
| mbedtls_ssl_set_inbound_transform ( ssl, ssl->transform_application ); |
| |
| MBEDTLS_SSL_DEBUG_MSG( 1, ( "Switch to application keys for outbound traffic" ) ); |
| mbedtls_ssl_set_outbound_transform( ssl, ssl->transform_application ); |
| |
| mbedtls_ssl_tls13_handshake_wrapup( ssl ); |
| |
| mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_HANDSHAKE_OVER ); |
| return( 0 ); |
| } |
| |
| int mbedtls_ssl_tls13_handshake_client_step( mbedtls_ssl_context *ssl ) |
| { |
| int ret = 0; |
| |
| MBEDTLS_SSL_DEBUG_MSG( 2, ( "tls13 client state: %s(%d)", |
| mbedtls_ssl_states_str( ssl->state ), |
| ssl->state ) ); |
| |
| switch( ssl->state ) |
| { |
| /* |
| * ssl->state is initialized as HELLO_REQUEST. It is the same |
| * as CLIENT_HELLO state. |
| */ |
| case MBEDTLS_SSL_HELLO_REQUEST: |
| case MBEDTLS_SSL_CLIENT_HELLO: |
| ret = ssl_tls13_write_client_hello( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_SERVER_HELLO: |
| ret = ssl_tls13_process_server_hello( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_ENCRYPTED_EXTENSIONS: |
| ret = ssl_tls13_process_encrypted_extensions( ssl ); |
| break; |
| |
| #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) |
| case MBEDTLS_SSL_CERTIFICATE_REQUEST: |
| ret = ssl_tls13_process_certificate_request( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_SERVER_CERTIFICATE: |
| ret = ssl_tls13_process_server_certificate( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_CERTIFICATE_VERIFY: |
| ret = ssl_tls13_process_certificate_verify( ssl ); |
| break; |
| #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */ |
| |
| case MBEDTLS_SSL_SERVER_FINISHED: |
| ret = ssl_tls13_process_server_finished( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_CLIENT_FINISHED: |
| ret = ssl_tls13_write_client_finished( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_FLUSH_BUFFERS: |
| ret = ssl_tls13_flush_buffers( ssl ); |
| break; |
| |
| case MBEDTLS_SSL_HANDSHAKE_WRAPUP: |
| ret = ssl_tls13_handshake_wrapup( ssl ); |
| break; |
| |
| /* |
| * Injection of dummy-CCS's for middlebox compatibility |
| */ |
| #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE) |
| case MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED: |
| ret = ssl_tls13_write_change_cipher_spec( ssl ); |
| break; |
| #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */ |
| |
| 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 */ |
| |
| #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */ |