bububa/gist:8580106

## gistfile1.txt
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>获取内网IP</title>
</head>
<body>
您的内网IP：
<span id="list"></span>
<script>
// NOTE: window.RTCPeerConnection is "not a constructor" in FF22/23
var RTCPeerConnection = /*window.RTCPeerConnection ||*/ window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
if (RTCPeerConnection) (function () {
var rtc = new RTCPeerConnection({iceServers:[]});
if (window.mozRTCPeerConnection) { // FF needs a channel/stream to proceed
rtc.createDataChannel('', {reliable:false});
};
rtc.onicecandidate = function (evt) {
if (evt.candidate) grepSDP(evt.candidate.candidate);
};
rtc.createOffer(function (offerDesc) {
grepSDP(offerDesc.sdp);
rtc.setLocalDescription(offerDesc);
}, function (e) { console.warn("offer failed", e); });
var addrs = Object.create(null);
addrs["0.0.0.0"] = false;
function updateDisplay(newAddr) {
if (newAddr in addrs) return;
else addrs[newAddr] = true;
var displayAddrs = Object.keys(addrs).filter(function (k) { return addrs[k]; });
document.getElementById('list').innerHTML = displayAddrs.join(" or perhaps ") || "n/a";
}
function grepSDP(sdp) {
var hosts = [];
sdp.split('\r\n').forEach(function (line) { // c.f.http://tools.ietf.org/html/rfc4566#page-39
if (~line.indexOf("a=candidate")) { //http://tools.ietf.org/html/rfc4566#section-5.13
var parts = line.split(' '), //http://tools.ietf.org/html/rfc5245#section-15.1
addr = parts[4],
type = parts[7];
if (type === 'host') updateDisplay(addr);
} else if (~line.indexOf("c=")) { //http://tools.ietf.org/html/rfc4566#section-5.7
var parts = line.split(' '),
addr = parts[2];
updateDisplay(addr);
}
});
}
})(); else {
document.getElementById('list').innerHTML = "<code>ifconfig | grep inet | grep -v inet6 | cut -d\" \" -f2 | tail -n1</code>";
document.getElementById('list').nextSibling.textContent = "In Chrome and Firefox your IP should display automatically, by the power of WebRTCskull.";
}
</script>
</body>
</html>
	<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
	<html xmlns="http://www.w3.org/1999/xhtml">
	<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
	<title>获取内网IP</title>
	</head>
	<body>
	您的内网IP：
	<span id="list"></span>
	<script>
	// NOTE: window.RTCPeerConnection is "not a constructor" in FF22/23
	var RTCPeerConnection = /window.RTCPeerConnection \|\|/ window.webkitRTCPeerConnection \|\| window.mozRTCPeerConnection;
	if (RTCPeerConnection) (function () {
	var rtc = new RTCPeerConnection({iceServers:[]});
	if (window.mozRTCPeerConnection) { // FF needs a channel/stream to proceed
	rtc.createDataChannel('', {reliable:false});
	};
	rtc.onicecandidate = function (evt) {
	if (evt.candidate) grepSDP(evt.candidate.candidate);
	};
	rtc.createOffer(function (offerDesc) {
	grepSDP(offerDesc.sdp);
	rtc.setLocalDescription(offerDesc);
	}, function (e) { console.warn("offer failed", e); });
	var addrs = Object.create(null);
	addrs["0.0.0.0"] = false;
	function updateDisplay(newAddr) {
	if (newAddr in addrs) return;
	else addrs[newAddr] = true;
	var displayAddrs = Object.keys(addrs).filter(function (k) { return addrs[k]; });
	document.getElementById('list').innerHTML = displayAddrs.join(" or perhaps ") \|\| "n/a";
	}
	function grepSDP(sdp) {
	var hosts = [];
	sdp.split('\r\n').forEach(function (line) { // c.f.http://tools.ietf.org/html/rfc4566#page-39
	if (~line.indexOf("a=candidate")) { //http://tools.ietf.org/html/rfc4566#section-5.13
	var parts = line.split(' '), //http://tools.ietf.org/html/rfc5245#section-15.1
	addr = parts[4],
	type = parts[7];
	if (type === 'host') updateDisplay(addr);
	} else if (~line.indexOf("c=")) { //http://tools.ietf.org/html/rfc4566#section-5.7
	var parts = line.split(' '),
	addr = parts[2];
	updateDisplay(addr);
	}
	});
	}
	})(); else {
	document.getElementById('list').innerHTML = "<code>ifconfig \| grep inet \| grep -v inet6 \| cut -d\" \" -f2 \| tail -n1</code>";
	document.getElementById('list').nextSibling.textContent = "In Chrome and Firefox your IP should display automatically, by the power of WebRTCskull.";
	}
	</script>
	</body>
	</html>