block media going back to Five9 voicestream

Co-authored-by: Markus Frindt <m.frindt@cognigy.com>

Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=linux/amd64 node:18.8.0-alpine as base
+FROM --platform=linux/amd64 node:18.9.0-alpine3.16 as base
 
 RUN apk --update --no-cache add --virtual .builds-deps build-base python3
 

lib/call-session.js

@@ -80,6 +80,10 @@ class CallSession extends Emitter {
     return tp && -1 !== tp.indexOf('SAVP');
   }
 
+  get isFive9VoiceStream() {
+    return this.req.has('X-Five9-StreamingPairId');
+  }
+
   async connect() {
     const {sdp} = this.req.locals;
     this.logger.info('inbound call accepted for routing');
@@ -168,6 +172,13 @@ class CallSession extends Emitter {
         throw new Error('rtpengine failed: answer');
       }
 
+      /* special case: Five9 Voicestream calls do not advertise a:sendonly, though they should */
+      if (this.isFive9VoiceStream) {
+        this.logger.info('Voicestream call from Five9, blocking audio in the reverse direction');
+        const response = Promise.all([this.blockMedia(opts), this.blockDTMF(opts)]);
+        this.logger.debug({response}, 'response to blocMedia');
+      }
+
       let headers = {
         'From': createBLegFromHeader(this.req),
         'To': this.req.get('To'),
@@ -508,11 +519,16 @@ Duration=${payload.duration} `
         req.body;
 
       const reason = req.get('X-Reason');
+      const isReleasingMedia = reason && dlg.type === 'uas' && ['release-media', 'anchor-media'].includes(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;
       const answerMedia = dlg.type === 'uas' ? this.rtpEngineOpts.uas.mediaOpts : this.rtpEngineOpts.uac.mediaOpts;
       const direction =  dlg.type === 'uas' ? ['public', 'private'] : ['private', 'public'];
+      if (isReleasingMedia) {
+        if (!offerMedia.flags.includes('asymmetric')) offerMedia.flags.push('asymmetric');
+        offerMedia.flags = offerMedia.flags.filter((f) => f !== 'media handover');
+      }
       let opts = {
         ...this.rtpEngineOpts.common,
         ...offerMedia,
@@ -531,11 +547,11 @@ Duration=${payload.duration} `
 
       /* 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.callerIsUsingSrtp) {
+      if (isReleasingMedia && !this.callerIsUsingSrtp) {
         this.logger.info({response}, `got a reinvite from FS to ${reason}`);
         sdp = dlg.other.remote.sdp;
-        answerMedia.flags = ['asymmetric', 'port latching'];
+        if (!answerMedia.flags.includes('asymmetric')) answerMedia.flags.push('asymmetric');
+        answerMedia.flags = answerMedia.flags.filter((f) => f !== 'media handover');
         this._mediaReleased = 'release-media' === reason;
       }
       else {
@@ -776,10 +792,10 @@ Duration=${payload.duration} `
       res.send(202);
 
       // invite to new fs
-      const headers = {};
-      if (req.has('X-Retain-Call-Sid')) {
-        Object.assign(headers, {'X-Retain-Call-Sid': req.get('X-Retain-Call-Sid')});
-      }
+      const headers = {
+        ...(req.has('X-Retain-Call-Sid') && {'X-Retain-Call-Sid': req.get('X-Retain-Call-Sid')}),
+        ...(req.has('X-Account-Sid') && {'X-Account-Sid': req.get('X-Account-Sid')})
+      };
       const uac = await this.srf.createUAC(referTo.uri, {localSdp: dlg.local.sdp, headers});
       this.uac = uac;
       uac.other = this.uas;

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "sbc-inbound",
-  "version": "v0.7.6",
+  "version": "v0.7.7",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "sbc-inbound",
-      "version": "v0.7.6",
+      "version": "v0.7.7",
       "license": "MIT",
       "dependencies": {
         "@jambonz/db-helpers": "^0.6.19",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sbc-inbound",
-  "version": "v0.7.6",
+  "version": "v0.7.7",
   "main": "app.js",
   "engines": {
     "node": ">= 12.0.0"