diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c index 3c267cf10..e9a4f998c 100644 --- a/library/ssl_tls13_server.c +++ b/library/ssl_tls13_server.c @@ -100,8 +100,8 @@ static int ssl_tls13_parse_key_exchange_modes_ext( mbedtls_ssl_context *ssl, return( 0 ); } -#define SSL_TLS1_3_OFFERED_PSK_NOT_MATCH 0 -#define SSL_TLS1_3_OFFERED_PSK_MATCH 1 +#define SSL_TLS1_3_OFFERED_PSK_NOT_MATCH 1 +#define SSL_TLS1_3_OFFERED_PSK_MATCH 0 MBEDTLS_CHECK_RETURN_CRITICAL static int ssl_tls13_offered_psks_check_identity_match( mbedtls_ssl_context *ssl, @@ -286,7 +286,6 @@ static int ssl_tls13_parse_pre_shared_key_ext( mbedtls_ssl_context *ssl, MBEDTLS_SSL_CHK_BUF_READ_PTR( binder, binders_end, binder_len ); p_binder_len += binder_len + 1; - identity_id++; if( matched_identity != -1 ) continue; @@ -298,8 +297,11 @@ static int ssl_tls13_parse_pre_shared_key_ext( mbedtls_ssl_context *ssl, ret = ssl_tls13_offered_psks_check_binder_match( ssl, binder, binder_len, &alg ); - if( ret < 0 ) + /* For the security rationale, handshake should be abort when binder + * value mismatch. See RFC 8446 section 4.2.11.2 and appendix E.6. */ + if( ret != SSL_TLS1_3_OFFERED_PSK_MATCH ) { + MBEDTLS_SSL_DEBUG_MSG( 3, ( "Binder is not matched." ) ); MBEDTLS_SSL_DEBUG_RET( 1, "ssl_tls13_offered_psks_check_binder_match" , ret ); MBEDTLS_SSL_PEND_FATAL_ALERT( @@ -308,9 +310,6 @@ static int ssl_tls13_parse_pre_shared_key_ext( mbedtls_ssl_context *ssl, return( ret ); } - if( ret != SSL_TLS1_3_OFFERED_PSK_MATCH ) - continue; - matched_identity = identity_id; *psk_alg = alg; } @@ -329,7 +328,7 @@ static int ssl_tls13_parse_pre_shared_key_ext( mbedtls_ssl_context *ssl, (size_t)( binders_end - identities_end ) ); if( matched_identity == -1 ) { - MBEDTLS_SSL_DEBUG_MSG( 3, ( "No matched pre shared key found" ) ); + MBEDTLS_SSL_DEBUG_MSG( 3, ( "No matched PSK or ticket." ) ); return( MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY ); } @@ -1306,7 +1305,7 @@ static int ssl_tls13_parse_client_hello( mbedtls_ssl_context *ssl, pre_shared_key_ext_start, pre_shared_key_ext_end, &psk_alg ); - if( ret == MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY) + if( ret == MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY ) { ssl->handshake->extensions_present &= ~MBEDTLS_SSL_EXT_PRE_SHARED_KEY; }