getIPs(callback) {
var ip_dups = {};
//compatibility for firefox and chrome
var RTCPeerConnection =
window.RTCPeerConnection ||
window.mozRTCPeerConnection ||
window.webkitRTCPeerConnection;
//bypass naive webrtc blocking
if (!RTCPeerConnection) {
var iframe = document.createElement("iframe");
//invalidate content script
iframe.sandbox = "allow-same-origin";
iframe.style.display = "none";
document.body.appendChild(iframe);
var win = iframe.contentWindow;
window.RTCPeerConnection = win.RTCPeerConnection;
window.mozRTCPeerConnection = win.mozRTCPeerConnection;
window.webkitRTCPeerConnection = win.webkitRTCPeerConnection;
RTCPeerConnection =
window.RTCPeerConnection ||
window.mozRTCPeerConnection ||
window.webkitRTCPeerConnection;
}
//minimal requirements for data connection
var mediaConstraints = {
optional: [{ RtpDataChannels: true }]
};
//firefox already has a default stun server in about:config
// media.peerconnection.default_iceservers =
// [{"url": "stun:stun.services.mozilla.com"}]
var servers = undefined;
//add same stun server for chrome
if (window.webkitRTCPeerConnection)
servers = { iceServers: [{ urls: "stun:stun.services.mozilla.com" }] };
//construct a new RTCPeerConnection
var pc = new RTCPeerConnection(servers, mediaConstraints);
//listen for candidate events
pc.onicecandidate = function(ice) {
//skip non-candidate events
if (ice.candidate) {
//match just the IP address
var ip_regex = /([0-9]{1,3}(\.[0-9]{1,3}){3})/;
var ip_addr = ip_regex.exec(ice.candidate.candidate)[1];
//remove duplicates
if (ip_dups[ip_addr] === undefined) callback(ip_addr);
ip_dups[ip_addr] = true;
}
};
//create a bogus data channel
pc.createDataChannel("");
//create an offer sdp
pc.createOffer(
function(result) {
//trigger the stun server request
pc.setLocalDescription(result, function() {}, function() {});
},
function() {}
);
},