feat support invite private to private network (#111)

* feat support invite private to private network

* feat support invite private to private network

* support multi private cidrs

* fix review comment

* fix matching regex

* fix regex to extract IP from sip uri

lib/call-session.js

@@ -1,7 +1,7 @@
 const Emitter = require('events');
 const sdpTransform = require('sdp-transform');
 const SrsClient = require('@jambonz/siprec-client-utils');
-const {makeRtpEngineOpts, nudgeCallCounts} = require('./utils');
+const {makeRtpEngineOpts, nudgeCallCounts, isPrivateVoipNetwork} = require('./utils');
 const {forwardInDialogRequests} = require('drachtio-fn-b2b-sugar');
 const {SipError, stringifyUri, parseUri} = require('drachtio-srf');
 const debug = require('debug')('jambonz:sbc-outbound');
@@ -204,13 +204,19 @@ class CallSession extends Emitter {
           destUri = stringifyUri(uri);
           this.logger.info(`overriding destination user with ${dest}, so final uri is ${destUri}`);
         }
-        uris = [destUri];
+        uris = [{
+          private_network: contact.includes('transport=ws') ? false : await isPrivateVoipNetwork(destUri),
+          uri: destUri
+        }];
         if (!contact.includes('transport=ws')) {
           proxy = this.req.locals.registration.proxy;
         }
       }
       else if (this.req.locals.target === 'forward') {
-        uris = [this.req.uri];
+        uris = [{
+          private_network: await isPrivateVoipNetwork(this.req.uri),
+          uri: this.req.uri
+        }];
         if (this.req.has('X-SIP-Proxy')) {
           proxy = this.req.get('X-SIP-Proxy');
           if (!proxy.startsWith('sip:') && !proxy.startsWith('sips:')) proxy = `sip:${proxy}`;
@@ -220,9 +226,15 @@ class CallSession extends Emitter {
         const vmailParam = 'opaque=app:voicemail';
         proxy = `sip:${this.req.calledNumber}@sip.pstnhub.microsoft.com:5061;transport=tls`;
         if (this.req.uri.includes(vmailParam)) {
-          uris = [`sip:${this.req.calledNumber}@sip.pstnhub.microsoft.com;${vmailParam}`];
+          uris = [{
+            private_network: false,
+            uri: `sip:${this.req.calledNumber}@sip.pstnhub.microsoft.com;${vmailParam}`
+          }];
         }
-        else uris = [`sip:${this.req.calledNumber}@sip.pstnhub.microsoft.com`];
+        else uris = [{
+          private_network: false,
+          uri: `sip:${this.req.calledNumber}@sip.pstnhub.microsoft.com`
+        }];
         headers = {
           ...headers,
           Contact: `sip:${this.req.calledNumber}@${this.req.get('X-MS-Teams-Tenant-FQDN')}:5061;transport=tls`
@@ -301,6 +313,13 @@ class CallSession extends Emitter {
                 this.rtpEngineOpts = makeRtpEngineOpts(this.req, false, true, o.pad_crypto, true);
               }
             });
+            // Check private network for each gw
+            uris = await Promise.all(uris.map(async(u) => {
+              return {
+                private_network: await isPrivateVoipNetwork(u),
+                uri: u
+              };
+            }));
             this.logger.debug({uris, voip_carrier_sid}, 'selected outbound gateways for requested carrier');
           }
           else {
@@ -315,15 +334,22 @@ class CallSession extends Emitter {
         debug(`sending call to PSTN ${uris}`);
       }
 
+      // private_network should be called at last
+      uris = uris.sort((a, b) => a.private_network - b.private_network);
+      const toPrivate = uris.some((u) => u.private_network === true);
+      const toPublic = uris.some((u) => u.private_network === false);
+      let isOfferUpdatedToPrivate = toPrivate && !toPublic;
+
+
       // rtpengine 'offer'
       const opts = updateRtpEngineFlags(this.req.body, {
         ...this.rtpEngineOpts.common,
         ...this.rtpEngineOpts.uac.mediaOpts,
         'from-tag': this.rtpEngineOpts.uas.tag,
-        direction:  ['private', 'public'],
+        direction:  ['private', toPublic ? 'public' : 'private'],
         sdp: this.req.body
       });
-      const response = await this.offer(opts);
+      let response = await this.offer(opts);
       debug(`response from rtpengine to offer ${JSON.stringify(response)}`);
       this.logger.debug({offer: opts, response}, 'initial offer to rtpengine');
       if ('ok' !== response.result) {
@@ -338,7 +364,17 @@ class CallSession extends Emitter {
       let earlyMedia = false;
       while (uris.length) {
         let hdrs = { ...headers};
-        const uri = uris.shift();
+        const {private_network, uri} = uris.shift();
+        if (private_network && !isOfferUpdatedToPrivate) {
+          // Cannot make call to all public Uris, now come to talk with private network Uris
+          this.rtpEngineResource.destroy()
+            .catch((err) => this.logger.info({err}, 'Error destroying rtpe to re-connect to private network'));
+          response = await this.offer({
+            ...opts,
+            direction: ['private', 'private']
+          });
+          isOfferUpdatedToPrivate = true;
+        }
         const gw = mapGateways.get(uri);
         const passFailure = 0 === uris.length;  // only a single target
         if (0 === uris.length) {

lib/utils.js

@@ -1,6 +1,11 @@
 const rtpCharacteristics = require('../data/rtp-transcoding');
 const srtpCharacteristics = require('../data/srtp-transcoding');
 const debug = require('debug')('jambonz:sbc-outbound');
+const CIDRMatcher = require('cidr-matcher');
+const dns = require('dns');
+
+const cidrMatcher = process.env.PRIVATE_VOIP_NETWORK_CIDR ?
+  new CIDRMatcher(process.env.PRIVATE_VOIP_NETWORK_CIDR.split(',')) : null;
 
 function makeRtpEngineOpts(req, srcIsUsingSrtp, dstIsUsingSrtp, padCrypto, teams) {
   const from = req.getParsedHeader('from');
@@ -181,6 +186,29 @@ const nudgeCallCounts = async(logger, sids, nudgeOperator, writers) => {
   return {callsSP: null, calls: null, callsApp: null};
 };
 
+const isPrivateVoipNetwork = async(uri) => {
+  if (cidrMatcher) {
+    try {
+      const arr = /sips?:.*@(.*?)(:\d+)?(;.*)$/.exec(uri);
+      if (arr) {
+        const input = arr[1];
+        let addresses;
+        if (input.match(/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/)) {
+          addresses = [input];
+        } else {
+          addresses = await dns.resolve4(input);
+        }
+        for (const ip of addresses) {
+          if (cidrMatcher.contains(ip)) {
+            return true;
+          }
+        }
+      }
+    } catch (err) {}
+  }
+  return false;
+};
+
 module.exports = {
   makeRtpEngineOpts,
   selectHostPort,
@@ -190,5 +218,6 @@ module.exports = {
   equalsIgnoreOrder,
   systemHealth,
   createHealthCheckApp,
-  nudgeCallCounts
+  nudgeCallCounts,
+  isPrivateVoipNetwork
 };