Feature/minimal media anchoring (#11)

* add support for sitting behind a sip proxy that adds X-Forwarded-For header

* feature: release media from freeswitch

* handle mute/unmute

* fix for relaying INFO

* support for relaying dtmf via SIP INFO to FS

* deps

app.js

@@ -54,7 +54,10 @@ const {createSet, retrieveSet, addToSet, removeFromSet, incrKey, decrKey} = requ
   port: process.env.JAMBONES_REDIS_PORT || 6379
 }, logger);
 
-const {getRtpEngine, setRtpEngines} = require('@jambonz/rtpengine-utils')([], logger, {emitter: stats});
+const {getRtpEngine, setRtpEngines} = require('@jambonz/rtpengine-utils')([], logger, {
+  emitter: stats,
+  dtmfListenPort: process.env.DTMF_LISTEN_PORT || 22224
+});
 srf.locals = {...srf.locals,
   stats,
   queryCdrs,
@@ -96,7 +99,6 @@ if (process.env.DRACHTIO_HOST) {
   srf.on('connect', (err, hp) => {
     if (err) return this.logger.error({err}, 'Error connecting to drachtio server');
     logger.info(`connected to drachtio listening on ${hp}`);
-    if (process.env.SBC_ACCOUNT_SID) return;
 
     const hostports = hp.split(',');
     for (const hp of hostports) {
@@ -104,11 +106,12 @@ if (process.env.DRACHTIO_HOST) {
       if (arr && 'udp' === arr[1] && !matcher.contains(arr[2])) {
         logger.info(`adding sbc public address to database: ${arr[2]}`);
         srf.locals.sipAddress = arr[2];
-        addSbcAddress(arr[2]);
+        if (!process.env.SBC_ACCOUNT_SID) addSbcAddress(arr[2]);
       }
       else if (arr && 'tcp' === arr[1] && matcher.contains(arr[2])) {
         const hostport = `${arr[2]}:${arr[3]}`;
         logger.info(`adding sbc private address to redis: ${hostport}`);
+        srf.locals.privateSipAddress = hostport;
         srf.locals.addToRedis = () => addToSet(setName, hostport);
         srf.locals.removeFromRedis = () => removeFromSet(setName, hostport);
         srf.locals.addToRedis();

data/rtp-transcoding.json

@@ -3,6 +3,6 @@
   "DTLS": "off",
   "SDES": "off",
   "ICE": "remove",
-  "flags": ["media handover"],
+  "flags": ["media handover", "port latching"],
   "rtcp-mux": ["accept"]
 }

data/srtp-transcoding.json

@@ -3,14 +3,14 @@
     "transport-protocol": "UDP/TLS/RTP/SAVPF",
     "ICE": "force",
     "SDES": "off",
-    "flags": ["generate mid", "SDES-no", "media handover"],
+    "flags": ["generate mid", "SDES-no", "media handover", "port latching"],
     "rtcp-mux": ["require"]  
   },
   "teams": {
     "transport-protocol": "RTP/SAVP",
     "ICE": "force",
     "SDES": "off",
-    "flags": ["generate mid", "SDES-no", "media handover"],
+    "flags": ["generate mid", "SDES-no", "media handover", "port latching"],
     "rtcp-mux": ["accept"]
   }
 }

lib/call-session.js

@@ -39,6 +39,10 @@ class CallSession extends Emitter {
     return !!this.req.locals.msTeamsTenantFqdn;
   }
 
+  get privateSipAddress() {
+    return this.srf.locals.privateSipAddress;
+  }
+
   async connect() {
     this.logger.info('inbound call accepted for routing');
     const engine = this.getRtpEngine();
@@ -49,10 +53,26 @@ class CallSession extends Emitter {
       return this.res.send(480);
     }
     debug(`got engine: ${JSON.stringify(engine)}`);
-    const {offer, answer, del} = engine;
+    const {
+      offer,
+      answer,
+      del,
+      blockMedia,
+      unblockMedia,
+      blockDTMF,
+      unblockDTMF,
+      subscribeDTMF,
+      unsubscribeDTMF
+    } = engine;
     this.offer = offer;
     this.answer = answer;
     this.del = del;
+    this.blockMedia = blockMedia;
+    this.unblockMedia = unblockMedia;
+    this.blockDTMF = blockDTMF;
+    this.unblockDTMF = unblockDTMF;
+    this.subscribeDTMF = subscribeDTMF;
+    this.unsubscribeDTMF = unsubscribeDTMF;
 
     const featureServer = await this.getFeatureServer();
     if (!featureServer) {
@@ -98,13 +118,15 @@ class CallSession extends Emitter {
       }
 
       // now send the INVITE in towards the feature servers
-      const headers = {
+      let headers = {
         'From': createBLegFromHeader(this.req),
         'To': this.req.get('To'),
         'X-Account-Sid': this.req.locals.account_sid,
         'X-CID': this.req.get('Call-ID'),
-        'X-Forwarded-For': `${this.req.source_address}:${this.req.source_port}`
+        'X-Forwarded-For': `${this.req.source_address}`
       };
+      if (this.privateSipAddress) headers = {...headers, Contact: `<sip:${this.privateSipAddress}>`};
+
       const responseHeaders = {};
       if (this.req.locals.carrier) Object.assign(headers, {'X-Originating-Carrier': this.req.locals.carrier});
       if (this.req.locals.msTeamsTenantFqdn) {
@@ -136,7 +158,14 @@ class CallSession extends Emitter {
         proxy,
         headers,
         responseHeaders,
-        proxyRequestHeaders: ['all', '-Authorization', '-Max-Forwards', '-Record-Route', '-Session-Expires', 'Min-SE'],
+        proxyRequestHeaders: [
+          'all',
+          '-Authorization',
+          '-Max-Forwards',
+          '-Record-Route',
+          '-Session-Expires',
+          '-X-Subspace-Forwarded-For'
+        ],
         proxyResponseHeaders: ['all'],
         localSdpB: response.sdp,
         localSdpA: async(sdp, res) => {
@@ -179,12 +208,15 @@ class CallSession extends Emitter {
   }
 
   _setDlgHandlers(dlg) {
-    this.activeCallIds.set(this.req.get('Call-ID'), this);
+    const {callId} = dlg.sip;
+    this.activeCallIds.set(callId, this);
+    this.subscribeDTMF(this.logger, callId, this.rtpEngineOpts.uas.tag,
+      this._onDTMF.bind(this));
     dlg.on('destroy', () => {
       debug('call ended with normal termination');
       this.logger.info('call ended with normal termination');
       this.rtpEngineResource.destroy().catch((err) => {});
-      this.activeCallIds.delete(this.req.get('Call-ID'));
+      this.activeCallIds.delete(callId);
       if (dlg.other && dlg.other.connected) dlg.other.destroy().catch((e) => {});
     });
 
@@ -213,7 +245,7 @@ class CallSession extends Emitter {
         this.rtpEngineResource.destroy().catch((err) => {});
         this.activeCallIds.delete(this.req.get('Call-ID'));
         dlg.other.destroy().catch((e) => {});
-
+        this.unsubscribeDTMF(this.logger, this.req.get('Call-ID'), this.rtpEngineOpts.uas.tag);
         if (process.env.JAMBONES_HOSTING) {
           this.decrKey(this.callCountKey)
             .then((count) => this.logger.debug({key: this.callCountKey},
@@ -237,14 +269,49 @@ class CallSession extends Emitter {
         }
       });
     });
+
+    this.subscribeDTMF(this.logger, this.req.get('Call-ID'), this.rtpEngineOpts.uas.tag,
+      this._onDTMF.bind(this, uac));
+
     uas.on('modify', this._onReinvite.bind(this, uas));
     uac.on('modify', this._onReinvite.bind(this, uac));
 
     uac.on('refer', this._onFeatureServerTransfer.bind(this, uac));
     uas.on('refer', this._onRefer.bind(this, uas));
 
+    uas.on('info', this._onInfo.bind(this, uas));
+    uac.on('info', this._onInfo.bind(this, uac));
+
     // default forwarding of other request types
-    forwardInDialogRequests(uas, ['info', 'notify', 'options', 'message']);
+    forwardInDialogRequests(uas, ['notify', 'options', 'message']);
+  }
+
+  async _onDTMF(dlg, payload) {
+    this.logger.info({payload}, '_onDTMF');
+    try {
+      let dtmf;
+      switch (payload.event) {
+        case 10:
+          dtmf = '*';
+          break;
+        case 11:
+          dtmf = '#';
+          break;
+        default:
+          dtmf = '' + payload.event;
+          break;
+      }
+      await dlg.request({
+        method: 'INFO',
+        headers: {
+          'Content-Type': 'application/dtmf-relay'
+        },
+        body: `Signal=${dtmf}
+Duration=${payload.duration} `
+      });
+    } catch (err) {
+      this.logger.info({err}, 'Error sending INFO application/dtmf-relay');
+    }
   }
 
   /**
@@ -281,6 +348,8 @@ class CallSession extends Emitter {
         });
       }
 
+      this.unsubscribeDTMF(this.logger, this.req.get('Call-ID'), this.rtpEngineOpts.uas.tag);
+
       const uas = await this.srf.createUAS(req, res, {
         localSdp: response.sdp,
         headers
@@ -307,6 +376,7 @@ class CallSession extends Emitter {
         res.send(200, {body: dlg.local.sdp});
         return;
       }
+      const reason = req.get('X-Reason');
       const fromTag = dlg.type === 'uas' ? this.rtpEngineOpts.uas.tag : this.rtpEngineOpts.uac.tag;
       const toTag = dlg.type === 'uas' ? this.rtpEngineOpts.uac.tag : this.rtpEngineOpts.uas.tag;
       const offerMedia = dlg.type === 'uas' ? this.rtpEngineOpts.uac.mediaOpts : this.rtpEngineOpts.uas.mediaOpts;
@@ -320,13 +390,23 @@ class CallSession extends Emitter {
         direction,
         sdp: req.body,
       };
+      if (reason) opts.flags.push('reset');
 
       let response = await this.offer(opts);
       if ('ok' !== response.result) {
         res.send(488);
         throw new Error(`_onReinvite: rtpengine failed: offer: ${JSON.stringify(response)}`);
       }
-      const sdp = await dlg.other.modify(response.sdp);
+
+      /* if this is a re-invite from the FS to change media anchoring, avoid sending the reinvite out */
+      let sdp;
+      if (reason && dlg.type === 'uac' && ['release-media', 'anchor-media'].includes(reason)) {
+        this.logger.info(`got a reinvite from FS to ${reason}`);
+        sdp = dlg.other.remote.sdp;
+      }
+      else {
+        sdp = await dlg.other.modify(response.sdp);
+      }
       opts = {
         ...this.rtpEngineOpts.common,
         ...answerMedia,
@@ -345,6 +425,46 @@ class CallSession extends Emitter {
     }
   }
 
+  async _onInfo(dlg, req, res) {
+    const fromTag = dlg.type === 'uas' ? this.rtpEngineOpts.uas.tag : this.rtpEngineOpts.uac.tag;
+    try {
+      if (dlg.type === 'uac' && req.has('X-Reason')) {
+        const reason = req.get('X-Reason');
+        const opts = {
+          ...this.rtpEngineOpts.common,
+          flags: ['reset'],
+          'from-tag': fromTag
+        };
+        this.logger.info(`_onInfo: got request ${reason}`);
+        res.send(200);
+
+        if (reason.startsWith('mute')) {
+          const response = Promise.all([this.blockMedia(opts), this.blockDTMF(opts)]);
+          this.logger.info({response}, `_onInfo: response to rtpengine command for ${reason}`);
+        }
+        else if (reason.startsWith('unmute')) {
+          const response = Promise.all([this.unblockMedia(opts), this.unblockDTMF(opts)]);
+          this.logger.info({response}, `_onInfo: response to rtpengine command for ${reason}`);
+        }
+      }
+      else {
+        const immutableHdrs = ['via', 'from', 'to', 'call-id', 'cseq', 'max-forwards', 'content-length'];
+        const headers = {};
+        Object.keys(req.headers).forEach((h) => {
+          if (!immutableHdrs.includes(h)) headers[h] = req.headers[h];
+        });
+        const response = await dlg.other.request({method: 'INFO', headers, body: req.body});
+        const responseHeaders = {};
+        if (response.has('Content-Type')) {
+          Object.assign(responseHeaders, {'Content-Type': response.get('Content-Type')});
+        }
+        res.send(response.status, {headers: responseHeaders, body: response.body});
+      }
+    } catch (err) {
+      this.logger.info({err}, `Error handing INFO request on ${dlg.type} leg`);
+    }
+  }
+
   async _onFeatureServerTransfer(dlg, req, res) {
     try {
       const referTo = req.getParsedHeader('Refer-To');
@@ -444,6 +564,7 @@ class CallSession extends Emitter {
 
         // successfully connected
         this.logger.info('successfully connected new call leg for REFER');
+        this.unsubscribeDTMF(this.logger, this.req.get('Call-ID'), this.rtpEngineOpts.uas.tag);
         this.referInvite = null;
         sendNotify(this.uas, '200 OK');
         this.uas.destroy();

lib/middleware.js

@@ -73,6 +73,17 @@ module.exports = function(srf, logger) {
 
   const initLocals = (req, res, next) => {
     req.locals = req.locals || {};
+
+    /* check if forwarded by a proxy that applied an X-Forwarded-For Header */
+    if (req.has('X-Subspace-Forwarded-For')) {
+      const original_source_address = req.get('X-Subspace-Forwarded-For');
+      logger.info({
+        callId: req.get('Call-ID'),
+        original_source_address,
+        proxy_source_address: req.source_address,
+      }, 'overwriting source address for proxied SIP INVITE');
+      req.source_address = original_source_address;
+    }
     req.locals.cdr = initCdr(req);
     const callId = req.get('Call-ID');
     req.on('cancel', () => {

package.json

@@ -20,7 +20,7 @@
   },
   "scripts": {
     "start": "node app",
-    "test": "NODE_ENV=test JAMBONES_NETWORK_CIDR='127.0.0.1/32' JAMBONES_HOSTING=1 SBC_ACCOUNT_SID=ed649e33-e771-403a-8c99-1780eabbc803 JAMBONES_TIME_SERIES_HOST=127.0.0.1 JAMBONES_MYSQL_HOST=127.0.0.1 JAMBONES_MYSQL_USER=jambones_test JAMBONES_MYSQL_PASSWORD=jambones_test JAMBONES_MYSQL_DATABASE=jambones_test JAMBONES_REDIS_HOST=localhost JAMBONES_REDIS_PORT=16379 JAMBONES_LOGLEVEL=debug DRACHTIO_SECRET=cymru DRACHTIO_HOST=127.0.0.1 DRACHTIO_PORT=9060 JAMBONES_RTPENGINES=127.0.0.1:12222 JAMBONES_FEATURE_SERVERS=172.38.0.11 node test/ ",
+    "test": "NODE_ENV=test JAMBONES_NETWORK_CIDR='127.0.0.1/32' JAMBONES_HOSTING=1 SBC_ACCOUNT_SID=ed649e33-e771-403a-8c99-1780eabbc803 JAMBONES_TIME_SERIES_HOST=127.0.0.1 JAMBONES_MYSQL_HOST=127.0.0.1 JAMBONES_MYSQL_USER=jambones_test JAMBONES_MYSQL_PASSWORD=jambones_test JAMBONES_MYSQL_DATABASE=jambones_test JAMBONES_REDIS_HOST=localhost JAMBONES_REDIS_PORT=16379 JAMBONES_LOGLEVEL=error DRACHTIO_SECRET=cymru DRACHTIO_HOST=127.0.0.1 DRACHTIO_PORT=9060 JAMBONES_RTPENGINES=127.0.0.1:12222 JAMBONES_FEATURE_SERVERS=172.38.0.11 node test/ ",
     "coverage": "./node_modules/.bin/nyc --reporter html --report-dir ./coverage npm run test",
     "jslint": "eslint app.js lib"
   },
@@ -28,7 +28,7 @@
     "@jambonz/db-helpers": "^0.6.12",
     "@jambonz/http-authenticator": "^0.2.0",
     "@jambonz/realtimedb-helpers": "^0.4.8",
-    "@jambonz/rtpengine-utils": "^0.1.12",
+    "@jambonz/rtpengine-utils": "^0.1.14",
     "@jambonz/stats-collector": "^0.1.5",
     "@jambonz/time-series": "^0.1.5",
     "aws-sdk": "^2.848.0",
@@ -39,7 +39,7 @@
     "cidr-matcher": "^2.1.1",
     "debug": "^4.3.1",
     "drachtio-fn-b2b-sugar": "0.0.12",
-    "drachtio-srf": "^4.4.49",
+    "drachtio-srf": "^4.4.55",
     "pino": "^6.8.0",
     "rtpengine-client": "^0.2.0"
   },