MyFavMirrors
/
MeshCentral
mirror of https://github.com/Ylianst/MeshCentral.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Added websocket device to browser frame forwarding, #4172

This commit is contained in:
Ylian Saint-Hilaire 2022-06-28 11:05:15 -07:00
parent 91dead8e84
commit 8a8d9869dd
1 changed files with 92 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

104
apprelays.js
View File

@ -229,21 +229,29 @@ module.exports.CreateWebRelay = function (parent, db, args, domain) {
// Process a websocket request
obj.processWebSocket = function (req, ws) {
//console.log('processWebSocket', req.url);
if (obj.relayActive == false) { console.log("ERROR: Attempt to use an unconnected tunnel"); return false; }
parent.lastOperation = obj.lastOperation = Date.now();
console.log('processWebSocket', req.url);
// Mark this tunnel as being a web socket tunnel
obj.isWebSocket = true;
obj.ws = ws;
// Pause the websocket until we get a tunnel connected
obj.ws._socket.pause();
// Remove the trailing '/.websocket' if needed
if (req.url.endsWith('/.websocket')) { req.url = req.url.substring(0, req.url.length - 11); }
if (obj.relayActive == false) { console.log("ERROR: Attempt to use an unconnected tunnel"); return false; }
parent.lastOperation = obj.lastOperation = Date.now();
// Construct the HTTP request and send it out
var request = req.method + ' ' + req.url + ' HTTP/' + req.httpVersion + '\r\n';
request += 'host: ' + obj.addr + ':' + obj.port + '\r\n';
const blockedHeaders = ['origin', 'host', 'cookie']; // These are headers we do not forward
const blockedHeaders = ['origin', 'host', 'cookie', 'sec-websocket-extensions']; // These are headers we do not forward
for (var i in req.headers) { if (blockedHeaders.indexOf(i) == -1) { request += i + ': ' + req.headers[i] + '\r\n'; } }
if (parent.webCookie != null) { request += 'cookie: ' + parent.webCookie + '\r\n' } // If we have a sessin cookie, use it.
request += '\r\n';
send(Buffer.from(request));
}
@ -397,7 +405,18 @@ module.exports.CreateWebRelay = function (parent, db, args, domain) {
// Check if this HTTP request has a body
if ((obj.socketXHeader['connection'] != null) && (obj.socketXHeader['connection'].toLowerCase() == 'close')) { obj.socketParseState = 1; }
if (obj.socketXHeader['content-length'] != null) { obj.socketParseState = 1; }
if ((obj.socketXHeader["transfer-encoding"] != null) && (obj.socketXHeader["transfer-encoding"].toLowerCase() == 'chunked')) { obj.socketParseState = 1; }
if ((obj.socketXHeader['transfer-encoding'] != null) && (obj.socketXHeader['transfer-encoding'].toLowerCase() == 'chunked')) { obj.socketParseState = 1; }
if (obj.isWebSocket) {
console.log('websocket', obj.socketXHeader);
if ((obj.socketXHeader['connection'] != null) && (obj.socketXHeader['connection'].toLowerCase() == 'upgrade')) {
console.log('websocket pass-thru');
obj.socketParseState = 2; // Switch to decoding websocket frames
obj.ws._socket.resume(); // Resume the browser's websocket
} else {
console.log('websocket failed');
obj.close(); // Failed to upgrade to websocket
}
}
// Forward the HTTP request into the tunnel, if no body is present, close the request.
processHttpResponse(obj.socketXHeader, null, (obj.socketParseState == 0));
@ -417,7 +436,8 @@ module.exports.CreateWebRelay = function (parent, db, args, domain) {
processHttpResponse(null, data, (obj.socketContentLengthRemaining == 0)); // Send any data we have, if we are done, signal the end of the response
if (obj.socketContentLengthRemaining > 0) return; // If more data is needed, return now so we exit the while() loop.
csize = 0; // We are done
} else if ((obj.socketXHeader["transfer-encoding"] != null) && (obj.socketXHeader["transfer-encoding"].toLowerCase() == 'chunked')) {
}
else if ((obj.socketXHeader['transfer-encoding'] != null) && (obj.socketXHeader['transfer-encoding'].toLowerCase() == 'chunked')) {
// The body is chunked
var clen = obj.socketAccumulator.indexOf('\r\n');
if (clen < 0) { return; } // Chunk length not found, exit now and get more data.
@ -438,23 +458,79 @@ module.exports.CreateWebRelay = function (parent, db, args, domain) {
if (obj.socketParseState == 2) {
// We are in websocket pass-thru mode, decode the websocket frame
if (obj.socketAccumulator.length < 2) return; // Need at least 2 bytes to decode a websocket header
console.log('WebSocket frame', obj.socketAccumulator.length, Buffer.from(obj.socketAccumulator, 'binary'));
//console.log('WebSocket frame', obj.socketAccumulator.length, Buffer.from(obj.socketAccumulator, 'binary'));
// Decode the websocket frame
const buf = Buffer.from(obj.socketAccumulator, 'binary');
const fin = ((buf[0] & 0x80) != 0);
const rsv = ((buf[0] & 0x70) != 0);
const op = buf[0] & 0x0F;
const mask = ((buf[1] & 0x80) != 0);
const len = buf[1] & 0x7F;
console.log('fin', fin);
console.log('op', op);
console.log('mask', mask);
console.log('len', len);
var len = buf[1] & 0x7F;
// Connection close
if ((fin == true) || (op == 8)) { obj.close(); }
// Calculate the total length
var payload = null;
if (len < 126) {
// 1 byte length
if (buf.length < (2 + len)) return; // Insuffisent data
payload = buf.slice(2, 2 + len);
obj.socketAccumulator = obj.socketAccumulator.substring(2 + len); // Remove data from accumulator
} else if (len == 126) {
// 2 byte length
if (buf.length < 4) return;
len = buf.readInt16BE(2);
if (buf.length < (4 + len)) return; // Insuffisent data
payload = buf.slice(4, 4 + len);
obj.socketAccumulator = obj.socketAccumulator.substring(4 + len); // Remove data from accumulator
} if (len == 127) {
// 8 byte length
if (buf.length < 10) return;
len = buf.readInt32BE(2);
if (len > 0) { obj.close(); return; } // This frame is larger than 4 gigabyte, close the connection.
len = buf.readInt32BE(6);
if (buf.length < (10 + len)) return; // Insuffisent data
payload = buf.slice(10, 10 + len);
obj.socketAccumulator = obj.socketAccumulator.substring(10 + len); // Remove data from accumulator
}
if (buf.length < len) return;
// If the mask or reserved bit are true, we are not decoding this right, close the connection.
if ((mask == true) || (rsv == true)) { obj.close(); return; }
// TODO: If FIN is not set, we need to add support for continue frames
// Perform operation
switch (op) {
case 0: { // Continue frame
//console.log('continue', payload.length);
break;
}
case 1: { // Text frame
//console.log('text', payload.length);
try { obj.ws.send(payload.toString('binary')); } catch (ex) { }
break;
}
case 2: { // Binary frame
//console.log('binary', payload.length);
try { obj.ws.send(payload); } catch (ex) { }
break;
}
case 8: { // Connection close
obj.close();
return;
}
case 9: { // Ping frame
//console.log('ping', payload.length);
// TODO
break;
}
case 10: { // Pong frame
//console.log('pong', payload.length);
// TODO
break;
}
}
}
}
}