Add extension check for NewSessionTicket
@@ -2565,9 +2565,12 @@ static int ssl_tls13_parse_new_session_ticket_exts( mbedtls_ssl_context *ssl,
const unsigned char *end )
{
const unsigned char *p = buf;
+ uint32_t extensions_present;
((void) ssl);
+ extensions_present = MBEDTLS_SSL_EXT_NONE;
+
while( p < end )
{
unsigned int extension_type;
@@ -2580,6 +2583,27 @@ static int ssl_tls13_parse_new_session_ticket_exts( mbedtls_ssl_context *ssl,
MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, extension_data_len );
+ /* RFC 8446 page 35
+ *
+ * If an implementation receives an extension which it recognizes and which
+ * is not specified for the message in which it appears, it MUST abort the
+ * handshake with an "illegal_parameter" alert.
+ */
+ extensions_present |= mbedtls_tls13_get_extension_mask( extension_type );
+ MBEDTLS_SSL_DEBUG_MSG( 3,
+ ( "NewSessionTicket : received %s(%u) extension",
+ mbedtls_tls13_get_extension_name( extension_type ),
+ extension_type ) );
+ if( ( extensions_present & MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_NST ) == 0 )
+ {
+ MBEDTLS_SSL_DEBUG_MSG(
+ 3, ( "forbidden extension received." ) );
+ MBEDTLS_SSL_PEND_FATAL_ALERT(
+ MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER,
+ MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
+ return( MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
+ }
+
switch( extension_type )
{
case MBEDTLS_TLS_EXT_EARLY_DATA:
@@ -2587,11 +2611,18 @@ static int ssl_tls13_parse_new_session_ticket_exts( mbedtls_ssl_context *ssl,
break;
default:
+ MBEDTLS_SSL_DEBUG_MSG( 3,
+ ( "NewSessionTicket : received %s(%u) extension ( ignored )",
+ mbedtls_tls13_get_extension_name( extension_type ),
+ extension_type ) );
break;
}
+
p += extension_data_len;
}
+ MBEDTLS_SSL_TLS1_3_PRINT_EXTS( 3, "NewSessionTicket", extensions_present );
+
return( 0 );
}
