From 459a8914ab873d0f2cb7df7ccc764b872fc2b9d6 Mon Sep 17 00:00:00 2001
From: Daniel-Constantin Mierla <miconda@gmail.com>
Date: Sun, 8 Jan 2017 10:08:47 +0100
Subject: [PATCH] examples: kemi - added basic script for jsdt engine

---
 .../examples/kemi/kamailio-basic-kemi-jsdt.js | 381 ++++++++++++++++++
 1 file changed, 381 insertions(+)
 create mode 100644 misc/examples/kemi/kamailio-basic-kemi-jsdt.js

diff --git a/misc/examples/kemi/kamailio-basic-kemi-jsdt.js b/misc/examples/kemi/kamailio-basic-kemi-jsdt.js
new file mode 100644
index 00000000000..f5ea8d103f5
--- /dev/null
+++ b/misc/examples/kemi/kamailio-basic-kemi-jsdt.js
@@ -0,0 +1,381 @@
+// Kamailio - equivalent of routing blocks in JavaScript
+//
+// KSR - the new dynamic object exporting Kamailio functions
+// sr - the old static object exporting Kamailio functions
+//
+
+// global variables corresponding to defined values (e.g., flags) in kamailio.cfg
+var FLT_ACC=1
+var FLT_ACCMISSED=2
+var FLT_ACCFAILED=3
+var FLT_NATS=5
+
+FLB_NATB=6
+FLB_NATSIPPING=7
+
+// SIP request routing
+// equivalent of request_route{}
+function ksr_request_route()
+{
+	var METHOD = KSR.pv.get("$rm");
+	// KSR.sl.sl_send_reply(100,"Intelligent trying");
+	// KSR.info("===== request - from kamailio lua script\n");
+
+	// per request initial checks
+	ksr_route_reqinit();
+
+	// NAT detection
+	ksr_route_natdetect();
+
+	// CANCEL processing
+	if (METHOD == "CANCEL") {
+		if(KSR.tm.t_check_trans()>0) {
+			ksr_route_relay();
+		}
+		return;
+	}
+
+	// handle requests within SIP dialogs
+	ksr_route_withindlg();
+
+	// -- only initial requests (no To tag)
+
+	// handle retransmissions
+	if (KSR.tmx.t_precheck_trans()>0) {
+		KSR.tm.t_check_trans();
+		return;
+	}
+	if (KSR.tm.t_check_trans()==0) { return; }
+
+	// authentication
+	ksr_route_auth();
+
+	// record routing for dialog forming requests (in case they are routed)
+	// - remove preloaded route headers
+	KSR.hdr.remove("Route");
+	if (METHOD=="INVITE" || METHOD=="SUBSCRIBE") {
+		KSR.rr.record_route();
+	}
+
+	// account only INVITEs
+	if (METHOD=="INVITE") {
+		KSR.setflag(FLT_ACC); // do accounting
+	}
+
+	// dispatch requests to foreign domains
+	ksr_route_sipout();
+
+	// -- requests for my local domains
+
+	// handle registrations
+	ksr_route_registrar();
+
+	if (KSR.pv.is_null("$rU")) {
+		// request with no Username in RURI
+		KSR.sl.sl_send_reply(484, "Address Incomplete");
+		return;
+	}
+
+	// user location service
+	ksr_route_location();
+
+	return;
+}
+
+// wrapper around tm relay function
+function ksr_route_relay()
+{
+	// enable additional event routes for forwarded requests
+	// - serial forking, RTP relaying handling, a.s.o.
+	var METHOD = KSR.pv.get("$rm");
+	if (METHOD=="INVITE" || METHOD=="BYE" || METHOD=="SUBSCRIBE"
+			|| METHOD="UPDATE") {
+		if (KSR.tm.t_is_set("branch_route")<0) {
+			KSR.tm.t_on_branch("ksr_branch_manage");
+		}
+	}
+	if (METHOD=="INVITE" || METHOD=="SUBSCRIBE" || METHOD=="UPDATE") {
+		if (KSR.tm.t_is_set("onreply_route")<0) {
+			KSR.tm.t_on_reply("ksr_onreply_manage");
+		}
+	}
+
+	if (METHOD=="INVITE") {
+		if (KSR.tm.t_is_set("failure_route")<0) {
+			KSR.tm.t_on_failure("MANAGE_FAILURE");
+		}
+	}
+
+	if (KSR.tm.t_relay()<0) {
+		KSR.sl.sl_reply_error();
+	}
+	KSR.x.exit();
+}
+
+
+// Per SIP request initial checks
+function ksr_route_reqinit()
+{
+	if (!KSR.is_myself(KSR.pv.get("$si"))) {
+		if (!KSR.pv.is_null("$sht(ipban=>$si)")) {
+			// ip is already blocked
+			KSR.dbg("request from blocked IP - " + KSR.pv.get("$rm")
+					+ " from " + KSR.pv.get("$fu") + " (IP:"
+					+ KSR.pv.get("$si") + ":" + KSR.pv.get("$sp") + ")\n");
+			KSR.x.exit();
+		}
+		if (KSR.pike.pike_check_req()<0) {
+			KSR.err("ALERT: pike blocking " + KSR.pv.get("$rm")
+					+ " from " + KSR.pv.get("$fu") + " (IP:"
+					+ KSR.pv.get("$si") + ":" + KSR.pv.get("$sp") + ")\n");
+			KSR.pv.seti("$sht(ipban=>$si)", 1);
+			KSR.x.exit();
+		}
+	}
+	if (!KSR.pv.is_null("$ua")) {
+		var UA = KSR.pv.get("$ua");
+		if (UA.indexOf("friendly-scanner")>=0 || UA.indexOf("sipcli")>=0) {
+			KSR.sl.sl_send_reply(200, "OK");
+			KSR.x.exit();
+		}
+	}
+
+	if (KSR.maxfwd.process_maxfwd(10) < 0) {
+		KSR.sl.sl_send_reply(483,"Too Many Hops");
+		KSR.x.exit();
+	}
+
+	if (KSR.pv.get("$rm")=="OPTIONS"
+			&& KSR.is_myself(KSR.pv.get("$ru"))
+			&& KSR.pv.is_null("$rU")) {
+		KSR.sl.sl_send_reply(200,"Keepalive");
+		KSR.x.exit();
+	}
+
+	if (KSR.sanity.sanity_check(1511, 7)<0) {
+		KSR.err("Malformed SIP message from "
+				+ KSR.pv.get("$si") + ":" + KSR.pv.get("$sp") + "\n");
+		KSR.x.exit();
+	}
+}
+
+
+// Handle requests within SIP dialogs
+function ksr_route_withindlg()
+{
+	if (KSR.siputils.has_totag()<0) { return; }
+
+	var METHOD = KSR.pv.get("$rm");
+	// sequential request withing a dialog should
+	// take the path determined by record-routing
+	if (KSR.rr.loose_route()>0) {
+		ksr_route_dlguri();
+		if (METHOD=="BYE") {
+			KSR.setflag(FLT_ACC); // do accounting ...
+			KSR.setflag(FLT_ACCFAILED); // ... even if the transaction fails
+		} else if (METHOD=="ACK") {
+			// ACK is forwarded statelessy
+			ksr_route_natmanage();
+		} else if (METHOD=="NOTIFY") {
+			// Add Record-Route for in-dialog NOTIFY as per RFC 6665.
+			KSR.rr.record_route();
+		}
+		ksr_route_relay();
+		KSR.x.exit();
+	}
+	if (METHOD=="ACK") {
+		if (KSR.tm.t_check_trans() >0) {
+			// no loose-route, but stateful ACK;
+			// must be an ACK after a 487
+			// or e.g. 404 from upstream server
+			ksr_route_relay();
+			KSR.x.exit();
+		} else {
+			// ACK without matching transaction ... ignore and discard
+			KSR.x.exit();
+		}
+	}
+	KSR.sl.sl_send_reply(404, "Not here");
+	KSR.x.exit();
+}
+
+// Handle SIP registrations
+function ksr_route_registrar()
+{
+	if (KSR.pv.get("$rm")!="REGISTER") { return; }
+	if (KSR.isflagset(FLT_NATS)) {
+		KSR.setbflag(FLB_NATB);
+		// do SIP NAT pinging
+		KSR.setbflag(FLB_NATSIPPING);
+	}
+	if (KSR.registrar.save("location", 0)<0) {
+		KSR.sl.sl_reply_error();
+	}
+	KSR.x.exit();
+}
+
+// User location service
+function ksr_route_location()
+{
+	var rc = KSR.registrar.lookup("location");
+	if (rc<0) {
+		KSR.tm.t_newtran();
+		if (rc==-1 || rc==-3) {
+			KSR.sl.send_reply("404", "Not Found");
+			KSR.x.exit();
+		} else if (rc==-2) {
+			KSR.sl.send_reply("405", "Method Not Allowed");
+			KSR.x.exit();
+		}
+	}
+
+	// when routing via usrloc, log the missed calls also
+	if (KSR.pv.get("$rm")=="INVITE") {
+		KSR.setflag(FLT_ACCMISSED);
+	}
+
+	ksr_route_relay();
+	KSR.x.exit();
+}
+
+
+// IP authorization and user uthentication
+function ksr_route_auth()
+{
+	var METHOD = KSR.pv.get("$rm");
+	if (METHOD!="REGISTER") {
+		if (KSR.permissions.allow_source_address(1)>0) {
+			// source IP allowed
+			return;
+		}
+	}
+
+	if (METHOD=="REGISTER" || KSR.is_myself(KSR.pv.get("$fu"))) {
+		// authenticate requests
+		if (KSR.auth_db.auth_check(KSR.pv.get("$fd"), "subscriber", 1)<0) {
+			KSR.auth.auth_challenge(KSR.pv.get("$fd"), 0);
+			KSR.x.exit();
+		}
+		// user authenticated - remove auth header
+		if (METHOD!="REGISTER" && METHOD!="PUBLISH") {
+			KSR.auth.consume_credentials();
+		}
+	}
+
+	// if caller is not local subscriber, then check if it calls
+	// a local destination, otherwise deny, not an open relay here
+	if ((! KSR.is_myself(KSR.pv.get("$fu"))
+			&& (! KSR.is_myself(KSR.pv.get("$ru"))))) {
+		KSR.sl.sl_send_reply(403,"Not relaying");
+		KSR.x.exit();
+	}
+
+	return;
+}
+
+// Caller NAT detection
+function ksr_route_natdetect()
+{
+	KSR.force_rport();
+	if (KSR.nathelper.nat_uac_test(19)>0) {
+		if (KSR.pv.get("$rm")=="REGISTER") {
+			KSR.nathelper.fix_nated_register();
+		} else if (KSR.siputils.is_first_hop()>0) {
+			KSR.nathelper.set_contact_alias();
+		}
+		KSR.setflag(FLT_NATS);
+	}
+	return;
+}
+
+// RTPProxy control
+function ksr_route_natmanage()
+{
+	if (KSR.siputils.is_request()>0) {
+		if (KSR.siputils.has_totag()>0) {
+			if (KSR.rr.check_route_param("nat=yes")>0) {
+				KSR.setbflag(FLB_NATB);
+			}
+		}
+	}
+	if (! (KSR.isflagset(FLT_NATS) || KSR.isbflagset(FLB_NATB))) {
+		return;
+	}
+
+	KSR.rtpproxy.rtpproxy_manage("co");
+
+	if (KSR.siputils.is_request()>0) {
+		if (! KSR.siputils.has_totag()) {
+			if (KSR.tmx.t_is_branch_route()>0) {
+				KSR.rr.add_rr_param(";nat=yes");
+			}
+		}
+	}
+	if (KSR.siputils.is_reply()>0) {
+		if (KSR.isbflagset(FLB_NATB)) {
+			KSR.nathelper.set_contact_alias();
+		}
+	}
+	return;
+}
+
+// URI update for dialog requests
+function ksr_route_dlguri()
+{
+	if (! KSR.isdsturiset()) {
+		KSR.nathelper.handle_ruri_alias();
+	}
+	return;
+}
+
+// Routing to foreign domains
+function ksr_route_sipout()
+{
+	if (KSR.is_myself(KSR.pv.get("$ru"))) { return; }
+
+	KSR.hdr.append_hf("P-Hint: outbound\r\n");
+	ksr_route_relay();
+	KSR.xexit();;
+}
+
+// Manage outgoing branches
+// equivalent of branch_route[...]{}
+function ksr_branch_manage()
+{
+	KSR.dbg("new branch [" + KSR.pv.get("$T_branch_idx]")
+				+ " to " + KSR.pv.get("$ru") + "\n");
+	ksr_route_natmanage();
+	return;
+}
+
+// Manage incoming replies
+// equivalent of onreply_route[...]{}
+function ksr_onreply_manage()
+{
+	KSR.dbg("incoming reply\n");
+	var scode = KSR.pv.get("$rs");
+	if (scode>100 && scode<=299) {
+		ksr_route_natmanage();
+	}
+	return;
+}
+
+// Manage failure routing cases
+// equivalent of failure_route[...]{}
+function ksr_failure_manage()
+{
+	ksr_route_natmanage();
+
+	if (KSR.tm.t_is_canceled()>0) {
+		return;
+	}
+	return;
+}
+
+// SIP response handling
+// equivalent of reply_route{}
+function ksr_reply_route()
+{
+	KSR.info("===== response - from kamailio JS script\n");
+	return;
+}