telebit.js/wsclient.js

414 lines
12 KiB
JavaScript

(function () {
'use strict';
var WebSocket = require('ws');
var PromiseA = require('bluebird');
var sni = require('sni');
var Packer = require('tunnel-packer');
function run(copts) {
var tokens = [ copts.token ];
var activityTimeout = copts.activityTimeout || 2*60*1000;
var pongTimeout = copts.pongTimeout || 10*1000;
var wstunneler;
var authenticated = false;
var localclients = {};
var clientHandlers = {
onClose: function (cid, opts, err) {
wsHandlers.sendMessage(Packer.pack(opts, null, err && 'error' || 'end'));
delete localclients[cid];
console.log('[local onClose] closed "' + cid + '" (' + clientHandlers.count() + ' clients)');
}
, onError: function(cid, opts, err) {
console.info("[local onError] closing '" + cid + "' because '" + err.message + "'");
clientHandlers.onClose(cid, opts, err);
}
, closeSingle: function (cid) {
if (!localclients[cid]) {
return;
}
console.log('[closeSingle]', cid);
try {
localclients[cid].end();
setTimeout(function () {
if (localclients[cid]) {
console.warn('[closeSingle]', cid, 'connection still present');
delete localclients[cid];
}
}, 500);
} catch (err) {
console.warn('[closeSingle] failed to close connection', cid, err);
delete localclients[cid];
}
}
, closeAll: function () {
console.log('[closeAll]');
Object.keys(localclients).forEach(function (cid) {
try {
localclients[cid].end();
} catch (err) {
console.warn('[closeAll] failed to close connection', cid, err);
}
});
setTimeout(function () {
Object.keys(localclients).forEach(function (cid) {
if (localclients[cid]) {
console.warn('[closeAll]', cid, 'connection still present');
delete localclients[cid];
}
});
}, 500);
}
, count: function () {
return Object.keys(localclients).length;
}
};
var pendingCommands = {};
function sendCommand(name) {
var id = Math.ceil(1e9 * Math.random());
var cmd = [id, name].concat(Array.prototype.slice.call(arguments, 1));
wsHandlers.sendMessage(Packer.pack(null, cmd, 'control'));
setTimeout(function () {
if (pendingCommands[id]) {
console.warn('command', id, 'timed out');
pendingCommands[id]({
message: 'response not received in time'
, code: 'E_TIMEOUT'
});
}
}, pongTimeout);
return new PromiseA(function (resolve, reject) {
pendingCommands[id] = function (err, result) {
delete pendingCommands[id];
if (err) {
reject(err);
} else {
resolve(result);
}
};
});
}
var packerHandlers = {
oncontrol: function (opts) {
var cmd, err;
try {
cmd = JSON.parse(opts.data.toString());
} catch (err) {}
if (!Array.isArray(cmd) || typeof cmd[0] !== 'number') {
console.warn('received bad command "' + opts.data.toString() + '"');
return;
}
if (cmd[0] < 0) {
var cb = pendingCommands[-cmd[0]];
if (!cb) {
console.warn('received response for unknown request:', cmd);
} else {
cb.apply(null, cmd.slice(1));
}
return;
}
// TODO: handle a "hello" message that let's us know we're authenticated.
err = { message: 'unknown command '+cmd[1], code: 'E_UNKNOWN_COMMAND' };
wsHandlers.sendMessage(Packer.pack(null, [-cmd[0], err], 'control'));
}
, onmessage: function (opts) {
var net = copts.net || require('net');
var cid = Packer.addrToId(opts);
var service = opts.service.toLowerCase();
var portList = copts.services[service];
var servername;
var port;
var str;
var m;
authenticated = true;
if (localclients[cid]) {
//console.log("[=>] received data from '" + cid + "' =>", opts.data.byteLength);
localclients[cid].write(opts.data);
return;
}
if (!portList) {
packerHandlers._onConnectError(cid, opts, new Error("unsupported service '" + service + "'"));
return;
}
if ('http' === service) {
str = opts.data.toString();
m = str.match(/(?:^|[\r\n])Host: ([^\r\n]+)[\r\n]*/im);
servername = (m && m[1].toLowerCase() || '').split(':')[0];
}
else if ('https' === service) {
servername = sni(opts.data);
}
else {
servername = '*';
}
if (!servername) {
//console.warn(opts.data.toString());
packerHandlers._onConnectError(cid, opts, new Error("missing servername for '" + cid + "' " + opts.data.byteLength));
return;
}
port = portList[servername] || portList['*'];
var createOpts = {
port: port
, host: '127.0.0.1'
, servername: servername
, data: opts.data
, remoteFamily: opts.family
, remoteAddress: opts.address
, remotePort: opts.port
};
localclients[cid] = net.createConnection(createOpts, function () {
// this will happen before 'data' or 'readable' is triggered
// We use the data from the createOpts object so that the createConnection function has
// the oppurtunity of removing/changing it if it wants/needs to handle it differently.
if (createOpts.data) {
localclients[cid].write(createOpts.data);
}
});
console.info("[connect] new client '" + cid + "' for '" + servername + "' (" + clientHandlers.count() + " clients)");
localclients[cid].on('readable', function (size) {
var chunk;
if (!localclients[cid]) {
console.error("[error] localclients[cid]", cid);
return;
}
if (!localclients[cid].read) {
console.error("[error] localclients[cid].read", cid);
console.log(localclients[cid]);
return;
}
do {
chunk = localclients[cid].read(size);
if (chunk) {
wsHandlers.sendMessage(Packer.pack(opts, chunk));
}
} while (chunk);
});
localclients[cid].on('error', clientHandlers.onError.bind(null, cid, opts));
localclients[cid].on('end', clientHandlers.onClose.bind(null, cid, opts));
}
, onend: function (opts) {
var cid = Packer.addrToId(opts);
//console.log("[end] '" + cid + "'");
clientHandlers.closeSingle(cid);
}
, onerror: function (opts) {
var cid = Packer.addrToId(opts);
//console.log("[error] '" + cid + "'", opts.code || '', opts.message);
clientHandlers.closeSingle(cid);
}
, _onConnectError: function (cid, opts, err) {
console.info("[_onConnectError] opening '" + cid + "' failed because " + err.message);
wsHandlers.sendMessage(Packer.pack(opts, null, 'error'));
}
};
var lastActivity;
var timeoutId;
var wsHandlers = {
refreshTimeout: function () {
lastActivity = Date.now();
}
, checkTimeout: function () {
if (!wstunneler) {
console.warn('checkTimeout called when websocket already closed');
return;
}
// Determine how long the connection has been "silent", ie no activity.
var silent = Date.now() - lastActivity;
// If we have had activity within the last activityTimeout then all we need to do is
// call this function again at the soonest time when the connection could be timed out.
if (silent < activityTimeout) {
timeoutId = setTimeout(wsHandlers.checkTimeout, activityTimeout-silent);
}
// Otherwise we check to see if the pong has also timed out, and if not we send a ping
// and call this function again when the pong will have timed out.
else if (silent < activityTimeout + pongTimeout) {
console.log('pinging tunnel server');
try {
wstunneler.ping();
} catch (err) {
console.warn('failed to ping tunnel server', err);
}
timeoutId = setTimeout(wsHandlers.checkTimeout, pongTimeout);
}
// Last case means the ping we sent before didn't get a response soon enough, so we
// need to close the websocket connection.
else {
console.log('connection timed out');
wstunneler.close(1000, 'connection timeout');
}
}
, onOpen: function () {
console.info("[open] connected to '" + copts.stunneld + "'");
wsHandlers.refreshTimeout();
timeoutId = setTimeout(wsHandlers.checkTimeout, activityTimeout);
tokens.forEach(function (jwtoken) {
sendCommand('add_token', jwtoken)
.catch(function (err) {
console.error('failed re-adding token', jwtoken, 'after reconnect', err);
// Not sure if we should do something like remove the token here. It worked
// once or it shouldn't have stayed in the list, so it's less certain why
// it would have failed here.
});
});
}
, onClose: function () {
console.log('ON CLOSE');
clearTimeout(timeoutId);
wstunneler = null;
clientHandlers.closeAll();
Object.keys(pendingCommands).forEach(function (id) {
pendingCommands[id]({
message: 'websocket connection closed before response'
, code: 'E_CONN_CLOSED'
});
});
if (!authenticated) {
console.info('[close] failed on first attempt... check authentication.');
timeoutId = null;
}
else if (tokens.length) {
console.info('[retry] disconnected and waiting...');
timeoutId = setTimeout(connect, 5000);
}
}
, onError: function (err) {
console.error("[tunnel error] " + err.message);
console.error(err);
}
, sendMessage: function (msg) {
if (wstunneler) {
try {
wstunneler.send(msg, {binary: true});
} catch (err) {
// There is a chance that this occurred after the websocket was told to close
// and before it finished, in which case we don't need to log the error.
if (wstunneler.readyState !== wstunneler.CLOSING) {
console.warn('[sendMessage] error sending websocket message', err);
}
}
}
}
};
function connect() {
if (!tokens.length) {
return;
}
timeoutId = null;
var machine = require('tunnel-packer').create(packerHandlers);
console.info("[connect] '" + copts.stunneld + "'");
var tunnelUrl = copts.stunneld.replace(/\/$/, '') + '/?access_token=' + tokens[0];
wstunneler = new WebSocket(tunnelUrl, { rejectUnauthorized: !copts.insecure });
wstunneler.on('open', wsHandlers.onOpen);
wstunneler.on('close', wsHandlers.onClose);
wstunneler.on('error', wsHandlers.onError);
// Our library will automatically handle sending the pong respose to ping requests.
wstunneler.on('ping', wsHandlers.refreshTimeout);
wstunneler.on('pong', wsHandlers.refreshTimeout);
wstunneler.on('message', function (data, flags) {
wsHandlers.refreshTimeout();
if (data.error || '{' === data[0]) {
console.log(data);
return;
}
machine.fns.addChunk(data, flags);
});
}
connect();
return {
end: function() {
tokens.length = 0;
if (timeoutId) {
clearTimeout(timeoutId);
timeoutId = null;
}
if (wstunneler) {
try {
wstunneler.close();
} catch(e) {
console.error("[error] wstunneler.close()");
console.error(e);
}
}
}
, append: function (token) {
if (tokens.indexOf(token) >= 0) {
return PromiseA.resolve();
}
tokens.push(token);
var prom = sendCommand('add_token', token);
prom.catch(function (err) {
console.error('adding token', token, 'failed:', err);
// Most probably an invalid token of some kind, so we don't really want to keep it.
tokens.splice(tokens.indexOf(token));
});
return prom;
}
, clear: function (token) {
if (typeof token === 'undefined') {
token = '*';
}
if (token === '*') {
tokens.length = 0;
} else {
var index = tokens.indexOf(token);
if (index < 0) {
return PromiseA.resolve();
}
tokens.splice(index);
}
var prom = sendCommand('delete_token', token);
prom.catch(function (err) {
console.error('clearing token', token, 'failed:', err);
});
return prom;
}
};
}
module.exports.connect = run;
module.exports.createConnection = run;
}());