####### Routing Logic ########
/* Main SIP request routing logic
 * - processing of any incoming SIP request starts with this route
 * - note: this is the same as route { ... } */
request_route {
	# per request initial checks
	route(REQINIT);
	# NAT detection
	route(NAT);
	
	# handle requests within SIP dialogs	
	route(WITHINDLG);	
	### only initial requests (no To tag)	
	# CANCEL processing	
	if (is_method("CANCEL"))	
	{	
		if (t_check_trans())	
			t_relay();	
		exit;	
	}

	t_check_trans();	
	# authentication	
	route(AUTH);	
	# record routing for dialog forming requests (in case they are routed)	
	# - remove preloaded route headers	
	remove_hf("Route");	
	if (is_method("INVITE|SUBSCRIBE"))	
		record_route();	
# account only INVITEs	
	if (is_method("INVITE"))	
	{	
		setflag(FLT_ACC); # do accounting	
	}	
	# dispatch requests to foreign domains	
	route(SIPOUT);	
	### requests for my local domains	
	# handle presence related requests	
	route(PRESENCE);	
	# handle registrations	
	route(REGISTRAR);	
	if ($rU==$null)	
	{	
		# request with no Username in RURI	
		sl_send_reply("484","Address Incomplete");	
		exit;	
	}	
	# dispatch destinations to PSTN	
	route(PSTN);	
	#!ifdef WITH_FREESWITCH	
	# save callee ID	
	$avp(callee) = $rU;	
	route(FSDISPATCH);	
	#!endif	
	# user location service	
	route(LOCATION);	
	route(RELAY);	
}	

route[RELAY] {	
#!ifdef WITH_NAT	
	if (check_route_param("nat=yes")) {	
		setbflag(FLB_NATB);	
	}	
	if (isflagset(FLT_NATS) || isbflagset(FLB_NATB)) {	
		route(RTPPROXY);	
	}	
#!endif

#!ifdef WITH_CFGSAMPLES	
	/* example how to enable some additional event routes */	
	if (is_method("INVITE")) {	
		#t_on_branch("BRANCH_ONE");	
		t_on_reply("REPLY_ONE");	
		t_on_failure("FAIL_ONE");	
	}	
#!endif

if (!t_relay()) {	
		sl_reply_error();	
	}	
	exit;	
}	
# Per SIP request initial checks	
route[REQINIT] {
#!ifdef WITH_ANTIFLOOD	
	# flood dection from same IP and traffic ban for a while	
	# be sure you exclude checking trusted peers, such as pstn gateways	
	# - local host excluded (e.g., loop to self)	
	if(src_ip!=myself)	
	{	
		if($sht(ipban=>$si)!=$null)	
		{	
			# ip is already blocked	
			xdbg("request from blocked IP - $rm from $fu (IP:$si:$sp)\n");	
			exit;	
		}	
		if (!pike_check_req())	
		{	
			xlog("L_ALERT","ALERT: pike blocking $rm from $fu (IP:$si:$sp)\n");	
			$sht(ipban=>$si) = 1;	
			exit;	
		}	
	}	
#!endif

if (!mf_process_maxfwd_header("10")) {	
		sl_send_reply("483","Too Many Hops");	
		exit;	
	}	
	if(!sanity_check("1511", "7"))	
	{	
		xlog("Malformed SIP message from $si:$sp\n");	
		exit;	
	}	
}

# Handle requests within SIP dialogs	
route[WITHINDLG] {	
	if (has_totag()) {	
		# sequential request withing a dialog should	
		# take the path determined by record-routing	
		if (loose_route()) {	
			if (is_method("BYE")) {	
				setflag(FLT_ACC); # do accounting ...	
				setflag(FLT_ACCFAILED); # ... even if the transaction fails	
			}
			route(RELAY);	
		} else {	
			if (is_method("SUBSCRIBE") && uri == myself) {	
				# in-dialog subscribe requests	
				route(PRESENCE);	
				exit;	
			}	
			if ( is_method("ACK") ) {	
				if ( t_check_trans() ) {	
					# no loose-route, but stateful ACK;	
					# must be an ACK after a 487	
					# or e.g. 404 from upstream server	
					t_relay();	
					exit;	
				} else {	
					# ACK without matching transaction ... ignore and discard	
					exit;	
				}	
			}	
			sl_send_reply("404","Not here");	
		}	
		exit;	
	}	
}

# Handle SIP registrations	
route[REGISTRAR] {	
	if (is_method("REGISTER"))	
	{	
		if(isflagset(FLT_NATS))	
		{	
			setbflag(FLB_NATB);	
			# uncomment next line to do SIP NAT pinging 	
			## setbflag(FLB_NATSIPPING);	
		}	
		if (!save("location"))	
			sl_reply_error();	
		exit;	
	}	
}

# USER location service	
route[LOCATION] {	
#!ifdef WITH_ALIASDB	
	# search in DB-based aliases	
	alias_db_lookup("dbaliases");	
#!endif	
	if (!lookup("location")) {	
		switch ($rc) {	
			case -1:	
			case -3:	
				t_newtran();	
				t_reply("404", "Not Found");	
				exit;	
			case -2:	
				sl_send_reply("405", "Method Not Allowed");	
				exit;	
		}	
	}	
	# when routing via usrloc, log the missed calls also	
	if (is_method("INVITE"))	
	{	
		setflag(FLT_ACCMISSED);	
	}	
}

# Presence server route	
route[PRESENCE] {	
	if(!is_method("PUBLISH|SUBSCRIBE"))	
		return;	
#!ifdef WITH_PRESENCE	
	if (!t_newtran())	
	{	
		sl_reply_error();	
		exit;	
	};	
	if(is_method("PUBLISH"))	
	{	
		handle_publish();	
		t_release();	
	}	
	else	
	if( is_method("SUBSCRIBE"))	
	{	
		handle_subscribe();	
		t_release();	
	}	
	exit;	
#!endif	
	# if presence enabled, this part will not be executed	
	if (is_method("PUBLISH") || $rU==$null)	
	{	
		sl_send_reply("404", "Not here");	
		exit;	
	}	
	return;	
}

	# Authentication route	
route[AUTH] {	
#!ifdef WITH_AUTH	
	if (is_method("REGISTER"))	
	{	
		# authenticate the REGISTER requests (uncomment to enable auth)	
		if (!www_authorize("$td", "subscriber"))	
		{	
			www_challenge("$td", "0");	
			exit;	
		}	
		if ($au!=$tU)	
		{	
			sl_send_reply("403","Forbidden auth ID");	
			exit;	
		}	
	} else {	
#!ifdef WITH_FREESWITCH	
	if(route(FSINBOUND))	
		return;	
#!endif	
#!ifdef WITH_IPAUTH	
		if(allow_source_address())	
		{	
			# source IP allowed	
			return;	
		}	
#!endif	

# authenticate if from local subscriber	
		if (from_uri==myself)	
		{	
			if (!proxy_authorize("$fd", "subscriber")) {	
				proxy_challenge("$fd", "0");	
				exit;	
			}	
			if (is_method("PUBLISH"))	
			{	
				if ($au!=$tU) {	
					sl_send_reply("403","Forbidden auth ID");	
					exit;	
				}	
			} else {	
				if ($au!=$fU) {	
					sl_send_reply("403","Forbidden auth ID");	
					exit;	
				}	
			}	
			consume_credentials();	
			# caller authenticated	
		} else {	
			# caller is not local subscriber, then check if it calls	
			# a local destination, otherwise deny, not an open relay here	
			if (!uri==myself)	
			{	
				sl_send_reply("403","Not relaying");	
				exit;	
			}	
		}	
	}	
#!endif	
	return;	
}	
# Caller NAT detection route	
route[NAT] {	
#!ifdef WITH_NAT	
	force_rport();	
	if (nat_uac_test("19")) {	
		if (method=="REGISTER") {	
			fix_nated_register();	
		} else {	
			fix_nated_contact();	
		}	
		setflag(FLT_NATS);	
	}	
#!endif	
	return;	
}	
# RTPProxy control	
route[RTPPROXY] {	
#!ifdef WITH_NAT	
	if (is_method("BYE")) {	
		unforce_rtp_proxy();	
	} else if (is_method("INVITE")){	
		force_rtp_proxy();	
	}	
	if (!has_totag()) add_rr_param(";nat=yes");	
#!endif	
	return;	
}	
# Routing to foreign domains	
route[SIPOUT] {	
	if (!uri==myself)	
	{	
		append_hf("P-hint: outbound\r\n");	
		route(RELAY);	
	}	
}	
# PSTN GW routing	
route[PSTN] {	
#!ifdef WITH_PSTN	
	# check if PSTN GW IP is defined	
	if (strempty($sel(cfg_get.pstn.gw_ip))) {	
		xlog("SCRIPT: PSTN rotuing enabled but pstn.gw_ip not defined\n");	
		return;	
	}	
	# route to PSTN dialed numbers starting with '+' or '00'	
	#     (international format)	
	# - update the condition to match your dialing rules for PSTN routing	
	if(!($rU=~"^(\+|00)[1-9][0-9]{3,20}$"))	
		return;	
	# only local users allowed to call	
	if(from_uri!=myself) {	
		sl_send_reply("403", "Not Allowed");	
		exit;	
	}	
	$ru = "sip:" + $rU + "@" + $sel(cfg_get.pstn.gw_ip);	
	route(RELAY);	
	exit;	
#!endif	
	return;	
}

# JSONRPC over HTTP(S) routing
#!ifdef WITH_JSONRPC
event_route[xhttp:request] {
	set_reply_close();
	set_reply_no_connect();
	if(src_ip!=127.0.0.1) {
		xhttp_reply("403", "Forbidden", "text/html",
				"<html><body>Not allowed from $si</body></html>");
		exit;
	}
	if ($hu =~ "^/RPC") {
		jsonrpc_dispatch();
		exit;
	}
	xhttp_reply("200", "OK", "text/html",
				"<html><body>Wrong URL $hu</body></html>");
    exit;
}
#!endif

#!ifdef WITH_FREESWITCH	
# FreeSWITCH routing blocks	
route[FSINBOUND] {	
	if($si== $sel(cfg_get.freeswitch.bindip)	
			&& $sp==$sel(cfg_get.freeswitch.bindport))	
		return 1;	
	return -1;	
}	
route[FSDISPATCH] {	
	if(!is_method("INVITE"))	
		return;	
	if(route(FSINBOUND))	
		return;	
	# dial number selection	
	switch($rU) {	
		case /"^41$":	
			# 41 - voicebox menu	
			# allow only authenticated users	
			if($au==$null)	
			{	
				sl_send_reply("403", "Not allowed");	
				exit;	
			}	
			$rU = "vm-" + $au;	
		break;	
		case /"^441[0-9][0-9]$":	
			# starting with 44 folowed by 1XY - direct call to voice box	
			strip(2);	
			route(FSVBOX);	
		break;	
		case /"^433[01][0-9][0-9]$":	
			# starting with 433 folowed by (0|1)XY - conference	
			strip(2);	
		break;	
		case /"^45[0-9]+$":	
			strip(2);	
		break;	
		default:	
			# offline - send to voicebox	
			if (!registered("location"))	
			{	
				route(FSVBOX);	
				exit;	
			}	
			# online - do bridging	
			prefix("kb-");	
			if(is_method("INVITE"))	
			{	
				# in case of failure - re-route to FreeSWITCH VoiceMail	
				t_on_failure("FAIL_FSVBOX");	
			}	
	}	
	route(FSRELAY);	
	exit;	
}	
route[FSVBOX] {	
	if(!($rU=~"^1[0-9][0-9]+$"))	
		return;	
	prefix("vb-");	
	route(FSRELAY);	
}	
# Send to FreeSWITCH	
route[FSRELAY] {	
	$du = "sip:" + $sel(cfg_get.freeswitch.bindip) + ":"	
			+ $sel(cfg_get.freeswitch.bindport);	
	if($var(newbranch)==1)	
	{	
		append_branch();	
		$var(newbranch) = 0;	
	}	
	route(RELAY);	
	exit;	
}	
#!endif	
# Sample branch router	
branch_route[BRANCH_ONE] {	
	xdbg("new branch at $ru\n");	
}	
# Sample onreply route	
onreply_route[REPLY_ONE] {	
	xdbg("incoming reply\n");	
#!ifdef WITH_NAT	
	if ((isflagset(FLT_NATS) || isbflagset(FLB_NATB))	
			&& status=~"(183)|(2[0-9][0-9])") {	
		force_rtp_proxy();	
	}	
	if (isbflagset("6")) {	
		fix_nated_contact();	
	}	
#!endif	
}


# Sample failure route	
failure_route[FAIL_ONE] {	
#!ifdef WITH_NAT	
	if (is_method("INVITE")	
			&& (isbflagset(FLB_NATB) || isflagset(FLT_NATS))) {	
		unforce_rtp_proxy();	
	}	
#!endif	
	if (t_is_canceled()) {	
		exit;	
	}	
	# uncomment the following lines if you want to block client 	
	# redirect based on 3xx replies.	
	##if (t_check_status("3[0-9][0-9]")) {	
	##t_reply("404","Not found");	
	##	exit;	
	##}	
	# uncomment the following lines if you want to redirect the failed 	
	# calls to a different new destination	
	##if (t_check_status("486|408")) {	
	##	sethostport("192.168.2.100:5060");	
	##	append_branch();	
	##	# do not set the missed call flag again	
	##	t_relay();	
	##}	
}	
#!ifdef WITH_FREESWITCH	
failure_route[FAIL_FSVBOX] {	
#!ifdef WITH_NAT	
	if (is_method("INVITE")	
			&& (isbflagset(FLB_NATB) || isflagset(FLT_NATS))) {	
		unforce_rtp_proxy();	
	}	
#!endif	
	if (t_is_canceled()) {	
		exit;	
	}	
	if (t_check_status("486|408")) {	
		# re-route to FreeSWITCH VoiceMail	
		$rU = $avp(callee);	
		$var(newbranch) = 1;	
		route(FSVBOX);	
	}	
}	
#!endif