################################ Routing Logic ######################################

route{
       # initial sanity checks -- messages with
       # max_forwards==0, or excessively long requests
       if (!mf_process_maxfwd_header("10")) {
               sl_send_reply("483","Too Many Hops");
               exit;
       };
       if (msg:len >= 2048 ) {
               sl_send_reply("513", "Message too big");
               exit;
       };
if (msg:len >= 2048 ) {
        sl_send_reply("513", "Message too big");
        exit;
};
# we record-route all messages -- to make sure that
# subsequent messages will go through our proxy; that's
# particularly good if upstream and downstream entities
# use different transport protocol
if (!method=="REGISTER")
        record_route();
# subsequent messages withing a dialog should take the
# path determined by record-routing
if (loose_route()) {
        # mark routing logic in request
        append_hf("P-hint: rr-enforced\r\n");
        route(1);
};

if (!uri==myself) {
        # mark routing logic in request
        append_hf("P-hint: outbound\r\n");
        # if you have some interdomain connections via TLS
        #if(uri=~"@tls_domain1.net") {
        #       t_relay("tls:domain1.net");
        #       exit;
   #} else if(uri=~"@tls_domain2.net") {
   #       t_relay("tls:domain2.net");
   #       exit;
   #}
   route(1);
};

if (is_method("INVITE"))
	{
		if (!do_routing("0")) {
    		send_reply("503", "No Rules matching the URI");
    		exit;
 	 }
		route(1);

	}

# if the request is for other domain use UsrLoc
# (in case, it does not work, use the following command
# with proper names and addresses in it)
if (uri==myself) {
        if (method=="REGISTER") {
                # Uncomment this if you want to use digest authentication
                #if (!www_authorize("openser.org","subscriber")) {
                #        www_challenge("openser.org", "0");
                #        exit;
                #};
                save("location");
                exit;
        };
}

lookup("aliases");
if (!uri==myself) {
        append_hf("P-hint: outbound alias\r\n");
        route(1);
};
        # native SIP destinations are handled using our USRLOC DB
        if (!lookup("location")) {
                 sl_send_reply("404", "Not Found");
                 exit;
        };
        append_hf("P-hint: usrloc applied\r\n");

route(1);




}

route[1] {
        # send it out now; use stateful forwarding as it works
        # reliably even for UDP2TCP
        if (!t_relay()) {
                sl_reply_error();
        };
        exit;
}