Don't allow transport=tcp when tcpenable=no.

When tcpenable=no, sending to transport=tcp hosts was still allowed.
Resolving the source address wasn't possible and yielded the string
"(null)" in SIP messages. Fixed that and a couple of not-so-correct
log messages.

(closes issue ASTERISK-18837)
Reported by: Andreas Topp

Review: https://reviewboard.asterisk.org/r/1585
Reviewed by: Matt Jordan
........

Merged revisions 347166 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 347167 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@347168 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -27870,12 +27870,14 @@ static struct sip_peer *build_peer(const char *name, struct ast_variable *v, str
 
 					if (!strncasecmp(trans, "udp", 3)) {
 						peer->transports |= SIP_TRANSPORT_UDP;
-					} else if (!strncasecmp(trans, "tcp", 3)) {
+					} else if (sip_cfg.tcp_enabled && !strncasecmp(trans, "tcp", 3)) {
 						peer->transports |= SIP_TRANSPORT_TCP;
-					} else if (!strncasecmp(trans, "tls", 3)) {
+					} else if (sip_cfg.tcp_enabled && !strncasecmp(trans, "tls", 3)) {
 						peer->transports |= SIP_TRANSPORT_TLS;
+					} else if (!sip_cfg.tcp_enabled && (!strncasecmp(trans, "tcp", 3) || !strncasecmp(trans, "tls", 3))) {
+						ast_log(LOG_WARNING, "'%s' is not a valid transport type when tcpenabled=no. if no other is specified, the defaults from general will be used.\n", trans);
 					} else {
-						ast_log(LOG_NOTICE, "'%s' is not a valid transport type. if no other is specified, udp will be used.\n", trans);
+						ast_log(LOG_NOTICE, "'%s' is not a valid transport type. if no other is specified, the defaults from general will be used.\n", trans);
 					}
 
 					if (!peer->default_outbound_transport) { /*!< The first transport listed should be default outbound */
@@ -29281,8 +29283,11 @@ static int reload_config(enum channelreloadreason reason)
 		ast_log(LOG_WARNING, "To disallow external domains, you need to configure local SIP domains.\n");
 		sip_cfg.allow_external_domains = 1;
 	}
-	/* If not configured, set default transports */
-	if (default_transports == 0) {
+	/* If not or badly configured, set default transports */
+	if (!sip_cfg.tcp_enabled && ((default_transports & SIP_TRANSPORT_TCP) || (default_transports & SIP_TRANSPORT_TLS))) {
+		ast_log(LOG_WARNING, "Cannot use 'tcp' or 'tls' transport with tcpenable=no. Falling back to 'udp'.\n");
+		default_transports = default_primary_transport = SIP_TRANSPORT_UDP;
+	} else if (default_transports == 0) {
 		default_transports = default_primary_transport = SIP_TRANSPORT_UDP;
 	}