/* jshint -W117 */ // SDP STUFF function SDP(sdp) { this.media = sdp.split('\r\nm='); for (var i = 1; i < this.media.length; i++) { this.media[i] = 'm=' + this.media[i]; if (i != this.media.length - 1) { this.media[i] += '\r\n'; } } this.session = this.media.shift() + '\r\n'; this.raw = this.session + this.media.join(''); } exports.SDP = SDP; var jsdom = require("jsdom"); var window = jsdom.jsdom().parentWindow; var $ = require('jquery')(window); var SDPUtil = require('./strophe.jingle.sdp.util.js').SDPUtil; /** * Returns map of MediaChannel mapped per channel idx. */ SDP.prototype.getMediaSsrcMap = function() { var self = this; var media_ssrcs = {}; for (channelNum = 0; channelNum < self.media.length; channelNum++) { modified = true; tmp = SDPUtil.find_lines(self.media[channelNum], 'a=ssrc:'); var type = SDPUtil.parse_mid(SDPUtil.find_line(self.media[channelNum], 'a=mid:')); var channel = new MediaChannel(channelNum, type); media_ssrcs[channelNum] = channel; tmp.forEach(function (line) { var linessrc = line.substring(7).split(' ')[0]; // allocate new ChannelSsrc if(!channel.ssrcs[linessrc]) { channel.ssrcs[linessrc] = new ChannelSsrc(linessrc, type); } channel.ssrcs[linessrc].lines.push(line); }); tmp = SDPUtil.find_lines(self.media[channelNum], 'a=ssrc-group:'); tmp.forEach(function(line){ var semantics = line.substr(0, idx).substr(13); var ssrcs = line.substr(14 + semantics.length).split(' '); if (ssrcs.length != 0) { var ssrcGroup = new ChannelSsrcGroup(semantics, ssrcs); channel.ssrcGroups.push(ssrcGroup); } }); } return media_ssrcs; }; /** * Returns true if this SDP contains given SSRC. * @param ssrc the ssrc to check. * @returns {boolean} true if this SDP contains given SSRC. */ SDP.prototype.containsSSRC = function(ssrc) { var channels = this.getMediaSsrcMap(); var contains = false; Object.keys(channels).forEach(function(chNumber){ var channel = channels[chNumber]; //console.log("Check", channel, ssrc); if(Object.keys(channel.ssrcs).indexOf(ssrc) != -1){ contains = true; } }); return contains; }; /** * Returns map of MediaChannel that contains only media not contained in otherSdp. Mapped by channel idx. * @param otherSdp the other SDP to check ssrc with. */ SDP.prototype.getNewMedia = function(otherSdp) { // this could be useful in Array.prototype. function arrayEquals(array) { // if the other array is a falsy value, return if (!array) return false; // compare lengths - can save a lot of time if (this.length != array.length) return false; for (var i = 0, l=this.length; i < l; i++) { // Check if we have nested arrays if (this[i] instanceof Array && array[i] instanceof Array) { // recurse into the nested arrays if (!this[i].equals(array[i])) return false; } else if (this[i] != array[i]) { // Warning - two different object instances will never be equal: {x:20} != {x:20} return false; } } return true; } var myMedia = this.getMediaSsrcMap(); var othersMedia = otherSdp.getMediaSsrcMap(); var newMedia = {}; Object.keys(othersMedia).forEach(function(channelNum) { var myChannel = myMedia[channelNum]; var othersChannel = othersMedia[channelNum]; if(!myChannel && othersChannel) { // Add whole channel newMedia[channelNum] = othersChannel; return; } // Look for new ssrcs accross the channel Object.keys(othersChannel.ssrcs).forEach(function(ssrc) { if(Object.keys(myChannel.ssrcs).indexOf(ssrc) === -1) { // Allocate channel if we've found ssrc that doesn't exist in our channel if(!newMedia[channelNum]){ newMedia[channelNum] = new MediaChannel(othersChannel.chNumber, othersChannel.mediaType); } newMedia[channelNum].ssrcs[ssrc] = othersChannel.ssrcs[ssrc]; } }); // Look for new ssrc groups across the channels othersChannel.ssrcGroups.forEach(function(otherSsrcGroup){ // try to match the other ssrc-group with an ssrc-group of ours var matched = false; for (var i = 0; i < myChannel.ssrcGroups.length; i++) { var mySsrcGroup = myChannel.ssrcGroups[i]; if (otherSsrcGroup.semantics == mySsrcGroup.semantics && arrayEquals.apply(otherSsrcGroup.ssrcs, [mySsrcGroup.ssrcs])) { matched = true; break; } } if (!matched) { // Allocate channel if we've found an ssrc-group that doesn't // exist in our channel if(!newMedia[channelNum]){ newMedia[channelNum] = new MediaChannel(othersChannel.chNumber, othersChannel.mediaType); } newMedia[channelNum].ssrcGroups.push(otherSsrcGroup); } }); }); return newMedia; }; // remove iSAC and CN from SDP SDP.prototype.mangle = function () { var i, j, mline, lines, rtpmap, newdesc; for (i = 0; i < this.media.length; i++) { lines = this.media[i].split('\r\n'); lines.pop(); // remove empty last element mline = SDPUtil.parse_mline(lines.shift()); if (mline.media != 'audio') continue; newdesc = ''; mline.fmt.length = 0; for (j = 0; j < lines.length; j++) { if (lines[j].substr(0, 9) == 'a=rtpmap:') { rtpmap = SDPUtil.parse_rtpmap(lines[j]); if (rtpmap.name == 'CN' || rtpmap.name == 'ISAC') continue; mline.fmt.push(rtpmap.id); newdesc += lines[j] + '\r\n'; } else { newdesc += lines[j] + '\r\n'; } } this.media[i] = SDPUtil.build_mline(mline) + '\r\n'; this.media[i] += newdesc; } this.raw = this.session + this.media.join(''); }; // remove lines matching prefix from session section SDP.prototype.removeSessionLines = function(prefix) { var self = this; var lines = SDPUtil.find_lines(this.session, prefix); lines.forEach(function(line) { self.session = self.session.replace(line + '\r\n', ''); }); this.raw = this.session + this.media.join(''); return lines; } // remove lines matching prefix from a media section specified by mediaindex // TODO: non-numeric mediaindex could match mid SDP.prototype.removeMediaLines = function(mediaindex, prefix) { var self = this; var lines = SDPUtil.find_lines(this.media[mediaindex], prefix); lines.forEach(function(line) { self.media[mediaindex] = self.media[mediaindex].replace(line + '\r\n', ''); }); this.raw = this.session + this.media.join(''); return lines; } // add content's to a jingle element SDP.prototype.toJingle = function (elem, thecreator) { var i, j, k, mline, ssrc, rtpmap, tmp, line, lines; var self = this; // new bundle plan if (SDPUtil.find_line(this.session, 'a=group:')) { lines = SDPUtil.find_lines(this.session, 'a=group:'); for (i = 0; i < lines.length; i++) { tmp = lines[i].split(' '); var semantics = tmp.shift().substr(8); elem.c('group', {xmlns: 'urn:xmpp:jingle:apps:grouping:0', semantics:semantics}); for (j = 0; j < tmp.length; j++) { elem.c('content', {name: tmp[j]}).up(); } elem.up(); } } // old bundle plan, to be removed var bundle = []; if (SDPUtil.find_line(this.session, 'a=group:BUNDLE')) { bundle = SDPUtil.find_line(this.session, 'a=group:BUNDLE ').split(' '); bundle.shift(); } for (i = 0; i < this.media.length; i++) { mline = SDPUtil.parse_mline(this.media[i].split('\r\n')[0]); if (!(mline.media === 'audio' || mline.media === 'video' || mline.media === 'application')) { continue; } if (SDPUtil.find_line(this.media[i], 'a=ssrc:')) { ssrc = SDPUtil.find_line(this.media[i], 'a=ssrc:').substring(7).split(' ')[0]; // take the first } else { ssrc = false; } elem.c('content', {creator: thecreator, name: mline.media}); if (SDPUtil.find_line(this.media[i], 'a=mid:')) { // prefer identifier from a=mid if present var mid = SDPUtil.parse_mid(SDPUtil.find_line(this.media[i], 'a=mid:')); elem.attrs({ name: mid }); // old BUNDLE plan, to be removed if (bundle.indexOf(mid) !== -1) { elem.c('bundle', {xmlns: 'http://estos.de/ns/bundle'}).up(); bundle.splice(bundle.indexOf(mid), 1); } } if (SDPUtil.find_line(this.media[i], 'a=rtpmap:').length) { elem.c('description', {xmlns: 'urn:xmpp:jingle:apps:rtp:1', media: mline.media }); if (ssrc) { elem.attrs({ssrc: ssrc}); } for (j = 0; j < mline.fmt.length; j++) { rtpmap = SDPUtil.find_line(this.media[i], 'a=rtpmap:' + mline.fmt[j]); elem.c('payload-type', SDPUtil.parse_rtpmap(rtpmap)); // put any 'a=fmtp:' + mline.fmt[j] lines into if (SDPUtil.find_line(this.media[i], 'a=fmtp:' + mline.fmt[j])) { tmp = SDPUtil.parse_fmtp(SDPUtil.find_line(this.media[i], 'a=fmtp:' + mline.fmt[j])); for (k = 0; k < tmp.length; k++) { elem.c('parameter', tmp[k]).up(); } } this.RtcpFbToJingle(i, elem, mline.fmt[j]); // XEP-0293 -- map a=rtcp-fb elem.up(); } if (SDPUtil.find_line(this.media[i], 'a=crypto:', this.session)) { elem.c('encryption', {required: 1}); var crypto = SDPUtil.find_lines(this.media[i], 'a=crypto:', this.session); crypto.forEach(function(line) { elem.c('crypto', SDPUtil.parse_crypto(line)).up(); }); elem.up(); // end of encryption } if (ssrc) { // new style mapping elem.c('source', { ssrc: ssrc, xmlns: 'urn:xmpp:jingle:apps:rtp:ssma:0' }); // FIXME: group by ssrc and support multiple different ssrcs var ssrclines = SDPUtil.find_lines(this.media[i], 'a=ssrc:'); ssrclines.forEach(function(line) { idx = line.indexOf(' '); var linessrc = line.substr(0, idx).substr(7); if (linessrc != ssrc) { elem.up(); ssrc = linessrc; elem.c('source', { ssrc: ssrc, xmlns: 'urn:xmpp:jingle:apps:rtp:ssma:0' }); } var kv = line.substr(idx + 1); elem.c('parameter'); if (kv.indexOf(':') == -1) { elem.attrs({ name: kv }); } else { elem.attrs({ name: kv.split(':', 2)[0] }); elem.attrs({ value: kv.split(':', 2)[1] }); } elem.up(); }); elem.up(); // old proprietary mapping, to be removed at some point tmp = SDPUtil.parse_ssrc(this.media[i]); tmp.xmlns = 'http://estos.de/ns/ssrc'; tmp.ssrc = ssrc; elem.c('ssrc', tmp).up(); // ssrc is part of description // XEP-0339 handle ssrc-group attributes var ssrc_group_lines = SDPUtil.find_lines(this.media[i], 'a=ssrc-group:'); ssrc_group_lines.forEach(function(line) { idx = line.indexOf(' '); var semantics = line.substr(0, idx).substr(13); var ssrcs = line.substr(14 + semantics.length).split(' '); if (ssrcs.length != 0) { elem.c('ssrc-group', { semantics: semantics, xmlns: 'urn:xmpp:jingle:apps:rtp:ssma:0' }); ssrcs.forEach(function(ssrc) { elem.c('source', { ssrc: ssrc }) .up(); }); elem.up(); } }); } if (SDPUtil.find_line(this.media[i], 'a=rtcp-mux')) { elem.c('rtcp-mux').up(); } // XEP-0293 -- map a=rtcp-fb:* this.RtcpFbToJingle(i, elem, '*'); // XEP-0294 if (SDPUtil.find_line(this.media[i], 'a=extmap:')) { lines = SDPUtil.find_lines(this.media[i], 'a=extmap:'); for (j = 0; j < lines.length; j++) { tmp = SDPUtil.parse_extmap(lines[j]); elem.c('rtp-hdrext', { xmlns: 'urn:xmpp:jingle:apps:rtp:rtp-hdrext:0', uri: tmp.uri, id: tmp.value }); if (tmp.hasOwnProperty('direction')) { switch (tmp.direction) { case 'sendonly': elem.attrs({senders: 'responder'}); break; case 'recvonly': elem.attrs({senders: 'initiator'}); break; case 'sendrecv': elem.attrs({senders: 'both'}); break; case 'inactive': elem.attrs({senders: 'none'}); break; } } // TODO: handle params elem.up(); } } elem.up(); // end of description } // map ice-ufrag/pwd, dtls fingerprint, candidates this.TransportToJingle(i, elem); if (SDPUtil.find_line(this.media[i], 'a=sendrecv', this.session)) { elem.attrs({senders: 'both'}); } else if (SDPUtil.find_line(this.media[i], 'a=sendonly', this.session)) { elem.attrs({senders: 'initiator'}); } else if (SDPUtil.find_line(this.media[i], 'a=recvonly', this.session)) { elem.attrs({senders: 'responder'}); } else if (SDPUtil.find_line(this.media[i], 'a=inactive', this.session)) { elem.attrs({senders: 'none'}); } if (mline.port == '0') { // estos hack to reject an m-line elem.attrs({senders: 'rejected'}); } elem.up(); // end of content } elem.up(); return elem; }; SDP.prototype.TransportToJingle = function (mediaindex, elem) { var i = mediaindex; var tmp; var self = this; elem.c('transport'); // XEP-0343 DTLS/SCTP if (SDPUtil.find_line(this.media[mediaindex], 'a=sctpmap:').length) { var sctpmap = SDPUtil.find_line( this.media[i], 'a=sctpmap:', self.session); if (sctpmap) { var sctpAttrs = SDPUtil.parse_sctpmap(sctpmap); elem.c('sctpmap', { xmlns: 'urn:xmpp:jingle:transports:dtls-sctp:1', number: sctpAttrs[0], /* SCTP port */ protocol: sctpAttrs[1], /* protocol */ }); // Optional stream count attribute if (sctpAttrs.length > 2) elem.attrs({ streams: sctpAttrs[2]}); elem.up(); } } // XEP-0320 var fingerprints = SDPUtil.find_lines(this.media[mediaindex], 'a=fingerprint:', this.session); fingerprints.forEach(function(line) { tmp = SDPUtil.parse_fingerprint(line); tmp.xmlns = 'urn:xmpp:jingle:apps:dtls:0'; elem.c('fingerprint').t(tmp.fingerprint); delete tmp.fingerprint; line = SDPUtil.find_line(self.media[mediaindex], 'a=setup:', self.session); if (line) { tmp.setup = line.substr(8); } elem.attrs(tmp); elem.up(); // end of fingerprint }); tmp = SDPUtil.iceparams(this.media[mediaindex], this.session); if (tmp) { tmp.xmlns = 'urn:xmpp:jingle:transports:ice-udp:1'; elem.attrs(tmp); // XEP-0176 if (SDPUtil.find_line(this.media[mediaindex], 'a=candidate:', this.session)) { // add any a=candidate lines var lines = SDPUtil.find_lines(this.media[mediaindex], 'a=candidate:', this.session); lines.forEach(function (line) { elem.c('candidate', SDPUtil.candidateToJingle(line)).up(); }); } } elem.up(); // end of transport } SDP.prototype.RtcpFbToJingle = function (mediaindex, elem, payloadtype) { // XEP-0293 var lines = SDPUtil.find_lines(this.media[mediaindex], 'a=rtcp-fb:' + payloadtype); lines.forEach(function (line) { var tmp = SDPUtil.parse_rtcpfb(line); if (tmp.type == 'trr-int') { elem.c('rtcp-fb-trr-int', {xmlns: 'urn:xmpp:jingle:apps:rtp:rtcp-fb:0', value: tmp.params[0]}); elem.up(); } else { elem.c('rtcp-fb', {xmlns: 'urn:xmpp:jingle:apps:rtp:rtcp-fb:0', type: tmp.type}); if (tmp.params.length > 0) { elem.attrs({'subtype': tmp.params[0]}); } elem.up(); } }); }; SDP.prototype.RtcpFbFromJingle = function (elem, payloadtype) { // XEP-0293 var media = ''; var tmp = elem.find('>rtcp-fb-trr-int[xmlns="urn:xmpp:jingle:apps:rtp:rtcp-fb:0"]'); if (tmp.length) { media += 'a=rtcp-fb:' + '*' + ' ' + 'trr-int' + ' '; if (tmp.attr('value')) { media += tmp.attr('value'); } else { media += '0'; } media += '\r\n'; } tmp = elem.find('>rtcp-fb[xmlns="urn:xmpp:jingle:apps:rtp:rtcp-fb:0"]'); tmp.each(function () { media += 'a=rtcp-fb:' + payloadtype + ' ' + $(this).attr('type'); if ($(this).attr('subtype')) { media += ' ' + $(this).attr('subtype'); } media += '\r\n'; }); return media; }; // construct an SDP from a jingle stanza SDP.prototype.fromJingle = function (jingle) { var self = this; this.raw = 'v=0\r\n' + 'o=- ' + '1923518516' + ' 2 IN IP4 0.0.0.0\r\n' +// FIXME 's=-\r\n' + 't=0 0\r\n'; // http://tools.ietf.org/html/draft-ietf-mmusic-sdp-bundle-negotiation-04#section-8 if ($(jingle).find('>group[xmlns="urn:xmpp:jingle:apps:grouping:0"]').length) { $(jingle).find('>group[xmlns="urn:xmpp:jingle:apps:grouping:0"]').each(function (idx, group) { var contents = $(group).find('>content').map(function (idx, content) { return content.getAttribute('name'); }).get(); if (contents.length > 0) { self.raw += 'a=group:' + (group.getAttribute('semantics') || group.getAttribute('type')) + ' ' + contents.join(' ') + '\r\n'; } }); } else if ($(jingle).find('>group[xmlns="urn:ietf:rfc:5888"]').length) { // temporary namespace, not to be used. to be removed soon. $(jingle).find('>group[xmlns="urn:ietf:rfc:5888"]').each(function (idx, group) { var contents = $(group).find('>content').map(function (idx, content) { return content.getAttribute('name'); }).get(); if (group.getAttribute('type') !== null && contents.length > 0) { self.raw += 'a=group:' + group.getAttribute('type') + ' ' + contents.join(' ') + '\r\n'; } }); } else { // for backward compability, to be removed soon // assume all contents are in the same bundle group, can be improved upon later var bundle = $(jingle).find('>content').filter(function (idx, content) { //elem.c('bundle', {xmlns:'http://estos.de/ns/bundle'}); return $(content).find('>bundle').length > 0; }).map(function (idx, content) { return content.getAttribute('name'); }).get(); if (bundle.length) { this.raw += 'a=group:BUNDLE ' + bundle.join(' ') + '\r\n'; } } this.session = this.raw; jingle.find('>content').each(function () { var m = self.jingle2media($(this)); self.media.push(m); }); // reconstruct msid-semantic -- apparently not necessary /* var msid = SDPUtil.parse_ssrc(this.raw); if (msid.hasOwnProperty('mslabel')) { this.session += "a=msid-semantic: WMS " + msid.mslabel + "\r\n"; } */ this.raw = this.session + this.media.join(''); }; // translate a jingle content element into an an SDP media part SDP.prototype.jingle2media = function (content) { var media = '', desc = content.find('description'), ssrc = desc.attr('ssrc'), self = this, tmp; var sctp = content.find( '>transport>sctpmap[xmlns="urn:xmpp:jingle:transports:dtls-sctp:1"]'); tmp = { media: desc.attr('media') }; tmp.port = '1'; if (content.attr('senders') == 'rejected') { // estos hack to reject an m-line. tmp.port = '0'; } if (content.find('>transport>fingerprint').length || desc.find('encryption').length) { if (sctp.length) tmp.proto = 'DTLS/SCTP'; else tmp.proto = 'RTP/SAVPF'; } else { tmp.proto = 'RTP/AVPF'; } if (!sctp.length) { tmp.fmt = desc.find('payload-type').map( function () { return this.getAttribute('id'); }).get(); media += SDPUtil.build_mline(tmp) + '\r\n'; } else { media += 'm=application 1 DTLS/SCTP ' + sctp.attr('number') + '\r\n'; media += 'a=sctpmap:' + sctp.attr('number') + ' ' + sctp.attr('protocol'); var streamCount = sctp.attr('streams'); if (streamCount) media += ' ' + streamCount + '\r\n'; else media += '\r\n'; } media += 'c=IN IP4 0.0.0.0\r\n'; if (!sctp.length) media += 'a=rtcp:1 IN IP4 0.0.0.0\r\n'; //tmp = content.find('>transport[xmlns="urn:xmpp:jingle:transports:ice-udp:1"]'); tmp = content.find('>bundle>transport[xmlns="urn:xmpp:jingle:transports:ice-udp:1"]'); //console.log('transports: '+content.find('>transport[xmlns="urn:xmpp:jingle:transports:ice-udp:1"]').length); //console.log('bundle.transports: '+content.find('>bundle>transport[xmlns="urn:xmpp:jingle:transports:ice-udp:1"]').length); //console.log("tmp fingerprint: "+tmp.find('>fingerprint').innerHTML); if (tmp.length) { if (tmp.attr('ufrag')) { media += SDPUtil.build_iceufrag(tmp.attr('ufrag')) + '\r\n'; } if (tmp.attr('pwd')) { media += SDPUtil.build_icepwd(tmp.attr('pwd')) + '\r\n'; } tmp.find('>fingerprint').each(function () { // FIXME: check namespace at some point media += 'a=fingerprint:' + this.getAttribute('hash'); media += ' ' + $(this).text(); media += '\r\n'; //console.log("mline "+media); if (this.getAttribute('setup')) { media += 'a=setup:' + this.getAttribute('setup') + '\r\n'; } }); } switch (content.attr('senders')) { case 'initiator': media += 'a=sendonly\r\n'; break; case 'responder': media += 'a=recvonly\r\n'; break; case 'none': media += 'a=inactive\r\n'; break; case 'both': media += 'a=sendrecv\r\n'; break; } media += 'a=mid:' + content.attr('name') + '\r\n'; /*if (content.attr('name') == 'video') { media += 'a=x-google-flag:conference' + '\r\n'; }*/ // // see http://code.google.com/p/libjingle/issues/detail?id=309 -- no spec though // and http://mail.jabber.org/pipermail/jingle/2011-December/001761.html if (desc.find('rtcp-mux').length) { media += 'a=rtcp-mux\r\n'; } if (desc.find('encryption').length) { desc.find('encryption>crypto').each(function () { media += 'a=crypto:' + this.getAttribute('tag'); media += ' ' + this.getAttribute('crypto-suite'); media += ' ' + this.getAttribute('key-params'); if (this.getAttribute('session-params')) { media += ' ' + this.getAttribute('session-params'); } media += '\r\n'; }); } desc.find('payload-type').each(function () { media += SDPUtil.build_rtpmap(this) + '\r\n'; if ($(this).find('>parameter').length) { media += 'a=fmtp:' + this.getAttribute('id') + ' '; media += $(this).find('parameter').map(function () { return (this.getAttribute('name') ? (this.getAttribute('name') + '=') : '') + this.getAttribute('value'); }).get().join('; '); media += '\r\n'; } // xep-0293 media += self.RtcpFbFromJingle($(this), this.getAttribute('id')); }); // xep-0293 media += self.RtcpFbFromJingle(desc, '*'); // xep-0294 tmp = desc.find('>rtp-hdrext[xmlns="urn:xmpp:jingle:apps:rtp:rtp-hdrext:0"]'); tmp.each(function () { media += 'a=extmap:' + this.getAttribute('id') + ' ' + this.getAttribute('uri') + '\r\n'; }); content.find('>bundle>transport[xmlns="urn:xmpp:jingle:transports:ice-udp:1"]>candidate').each(function () { media += SDPUtil.candidateFromJingle(this); }); // XEP-0339 handle ssrc-group attributes tmp = content.find('description>ssrc-group[xmlns="urn:xmpp:jingle:apps:rtp:ssma:0"]').each(function() { var semantics = this.getAttribute('semantics'); var ssrcs = $(this).find('>source').map(function() { return this.getAttribute('ssrc'); }).get(); if (ssrcs.length != 0) { media += 'a=ssrc-group:' + semantics + ' ' + ssrcs.join(' ') + '\r\n'; } }); tmp = content.find('description>source[xmlns="urn:xmpp:jingle:apps:rtp:ssma:0"]'); tmp.each(function () { var ssrc = this.getAttribute('ssrc'); $(this).find('>parameter').each(function () { media += 'a=ssrc:' + ssrc + ' ' + this.getAttribute('name'); if (this.getAttribute('value') && this.getAttribute('value').length) media += ':' + this.getAttribute('value'); media += '\r\n'; }); }); if (tmp.length === 0) { // fallback to proprietary mapping of a=ssrc lines tmp = content.find('description>ssrc[xmlns="http://estos.de/ns/ssrc"]'); if (tmp.length) { media += 'a=ssrc:' + ssrc + ' cname:' + tmp.attr('cname') + '\r\n'; media += 'a=ssrc:' + ssrc + ' msid:' + tmp.attr('msid') + '\r\n'; media += 'a=ssrc:' + ssrc + ' mslabel:' + tmp.attr('mslabel') + '\r\n'; media += 'a=ssrc:' + ssrc + ' label:' + tmp.attr('label') + '\r\n'; } } return media; };