diff --git a/library/ssl_tls.c b/library/ssl_tls.c index bd2c27057..ba586a05e 100644 --- a/library/ssl_tls.c +++ b/library/ssl_tls.c @@ -3458,7 +3458,6 @@ static int ssl_handle_possible_reconnect( mbedtls_ssl_context *ssl ) */ static int ssl_parse_record_header( mbedtls_ssl_context *ssl ) { - int ret; int major_ver, minor_ver; MBEDTLS_SSL_DEBUG_BUF( 4, "input record header", ssl->in_hdr, mbedtls_ssl_hdr_len( ssl ) ); @@ -3480,12 +3479,13 @@ static int ssl_parse_record_header( mbedtls_ssl_context *ssl ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "unknown record type" ) ); - if( ( ret = mbedtls_ssl_send_alert_message( ssl, - MBEDTLS_SSL_ALERT_LEVEL_FATAL, - MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ) ) != 0 ) - { - return( ret ); - } +#if defined(MBEDTLS_SSL_PROTO_DTLS) + /* Silently ignore invalid DTLS records as recommended by RFC 6347 + * Section 4.1.2.7 */ + if( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE ); return( MBEDTLS_ERR_SSL_INVALID_RECORD ); }