'use strict'; const assert = require('assert'); const Buffer = require('buffer').Buffer; const util = require('util'); const EventEmitter = require('events'); const UV_UDP_REUSEADDR = process.binding('constants').os.UV_UDP_REUSEADDR; const UDP = process.binding('udp_wrap').UDP; const SendWrap = process.binding('udp_wrap').SendWrap; const BIND_STATE_UNBOUND = 0; const BIND_STATE_BINDING = 1; const BIND_STATE_BOUND = 2; // lazily loaded var cluster = null; var dns = null; const errnoException = util._errnoException; const exceptionWithHostPort = util._exceptionWithHostPort; function lookup(address, family, callback) { if (!dns) dns = require('dns'); return dns.lookup(address, family, callback); } function lookup4(address, callback) { return lookup(address || '127.0.0.1', 4, callback); } function lookup6(address, callback) { return lookup(address || '::1', 6, callback); } function newHandle(type) { if (type === 'udp4') { const handle = new UDP(); handle.lookup = lookup4; return handle; } if (type === 'udp6') { const handle = new UDP(); handle.lookup = lookup6; handle.bind = handle.bind6; handle.send = handle.send6; return handle; } throw new Error('Bad socket type specified. Valid types are: udp4, udp6'); } exports._createSocketHandle = function(address, port, addressType, fd, flags) { // Opening an existing fd is not supported for UDP handles. assert(typeof fd !== 'number' || fd < 0); var handle = newHandle(addressType); if (port || address) { var err = handle.bind(address, port || 0, flags); if (err) { handle.close(); return err; } } return handle; }; function Socket(type, listener) { EventEmitter.call(this); if (type !== null && typeof type === 'object') { var options = type; type = options.type; } var handle = newHandle(type); handle.owner = this; this._handle = handle; this._receiving = false; this._bindState = BIND_STATE_UNBOUND; this.type = type; this.fd = null; // compatibility hack // If true - UV_UDP_REUSEADDR flag will be set this._reuseAddr = options && options.reuseAddr; if (typeof listener === 'function') this.on('message', listener); } util.inherits(Socket, EventEmitter); exports.Socket = Socket; exports.createSocket = function(type, listener) { return new Socket(type, listener); }; function startListening(socket) { socket._handle.onmessage = onMessage; // Todo: handle errors socket._handle.recvStart(); socket._receiving = true; socket._bindState = BIND_STATE_BOUND; socket.fd = -42; // compatibility hack socket.emit('listening'); } function replaceHandle(self, newHandle) { // Set up the handle that we got from master. newHandle.lookup = self._handle.lookup; newHandle.bind = self._handle.bind; newHandle.send = self._handle.send; newHandle.owner = self; // Replace the existing handle by the handle we got from master. self._handle.close(); self._handle = newHandle; } Socket.prototype.bind = function(port_ /*, address, callback*/) { var self = this; let port = port_; self._healthCheck(); if (this._bindState !== BIND_STATE_UNBOUND) throw new Error('Socket is already bound'); this._bindState = BIND_STATE_BINDING; if (typeof arguments[arguments.length - 1] === 'function') self.once('listening', arguments[arguments.length - 1]); if (port instanceof UDP) { replaceHandle(self, port); startListening(self); return self; } var address; var exclusive; if (port !== null && typeof port === 'object') { address = port.address || ''; exclusive = !!port.exclusive; port = port.port; } else { address = typeof arguments[1] === 'function' ? '' : arguments[1]; exclusive = false; } // defaulting address for bind to all interfaces if (!address && self._handle.lookup === lookup4) { address = '0.0.0.0'; } else if (!address && self._handle.lookup === lookup6) { address = '::'; } // resolve address first self._handle.lookup(address, function(err, ip) { if (err) { self._bindState = BIND_STATE_UNBOUND; self.emit('error', err); return; } if (!cluster) cluster = require('cluster'); var flags = 0; if (self._reuseAddr) flags |= UV_UDP_REUSEADDR; if (cluster.isWorker && !exclusive) { function onHandle(err, handle) { if (err) { var ex = exceptionWithHostPort(err, 'bind', ip, port); self.emit('error', ex); self._bindState = BIND_STATE_UNBOUND; return; } if (!self._handle) // handle has been closed in the mean time. return handle.close(); replaceHandle(self, handle); startListening(self); } cluster._getServer(self, { address: ip, port: port, addressType: self.type, fd: -1, flags: flags }, onHandle); } else { if (!self._handle) return; // handle has been closed in the mean time const err = self._handle.bind(ip, port || 0, flags); if (err) { var ex = exceptionWithHostPort(err, 'bind', ip, port); self.emit('error', ex); self._bindState = BIND_STATE_UNBOUND; // Todo: close? return; } startListening(self); } }); return self; }; // thin wrapper around `send`, here for compatibility with dgram_legacy.js Socket.prototype.sendto = function(buffer, offset, length, port, address, callback) { if (typeof offset !== 'number' || typeof length !== 'number') throw new Error('Send takes "offset" and "length" as args 2 and 3'); if (typeof address !== 'string') throw new Error(this.type + ' sockets must send to port, address'); this.send(buffer, offset, length, port, address, callback); }; function sliceBuffer(buffer, offset, length) { if (typeof buffer === 'string') buffer = Buffer.from(buffer); else if (!(buffer instanceof Buffer)) throw new TypeError('First argument must be a buffer or string'); offset = offset >>> 0; length = length >>> 0; return buffer.slice(offset, offset + length); } function fixBufferList(list) { const newlist = new Array(list.length); for (var i = 0, l = list.length; i < l; i++) { var buf = list[i]; if (typeof buf === 'string') newlist[i] = Buffer.from(buf); else if (!(buf instanceof Buffer)) return null; else newlist[i] = buf; } return newlist; } function enqueue(self, toEnqueue) { // If the send queue hasn't been initialized yet, do it, and install an // event handler that flushes the send queue after binding is done. if (!self._queue) { self._queue = []; self.once('listening', clearQueue); } self._queue.push(toEnqueue); return; } function clearQueue() { const queue = this._queue; this._queue = undefined; // Flush the send queue. for (var i = 0; i < queue.length; i++) queue[i](); } // valid combinations // send(buffer, offset, length, port, address, callback) // send(buffer, offset, length, port, address) // send(buffer, offset, length, port) // send(bufferOrList, port, address, callback) // send(bufferOrList, port, address) // send(bufferOrList, port) Socket.prototype.send = function(buffer, offset, length, port, address, callback) { const self = this; let list; if (address || (port && typeof port !== 'function')) { buffer = sliceBuffer(buffer, offset, length); } else { callback = port; port = offset; address = length; } if (!Array.isArray(buffer)) { if (typeof buffer === 'string') { list = [ Buffer.from(buffer) ]; } else if (!(buffer instanceof Buffer)) { throw new TypeError('First argument must be a buffer or a string'); } else { list = [ buffer ]; } } else if (!(list = fixBufferList(buffer))) { throw new TypeError('Buffer list arguments must be buffers or strings'); } port = port >>> 0; if (port === 0 || port > 65535) throw new RangeError('Port should be > 0 and < 65536'); // Normalize callback so it's either a function or undefined but not anything // else. if (typeof callback !== 'function') callback = undefined; self._healthCheck(); if (self._bindState === BIND_STATE_UNBOUND) self.bind({port: 0, exclusive: true}, null); if (list.length === 0) list.push(Buffer.alloc(0)); // If the socket hasn't been bound yet, push the outbound packet onto the // send queue and send after binding is complete. if (self._bindState !== BIND_STATE_BOUND) { enqueue(self, self.send.bind(self, list, port, address, callback)); return; } self._handle.lookup(address, function afterDns(ex, ip) { doSend(ex, self, ip, list, address, port, callback); }); }; function doSend(ex, self, ip, list, address, port, callback) { if (ex) { if (typeof callback === 'function') { callback(ex); return; } self.emit('error', ex); return; } else if (!self._handle) { return; } var req = new SendWrap(); req.list = list; // Keep reference alive. req.address = address; req.port = port; if (callback) { req.callback = callback; req.oncomplete = afterSend; } var err = self._handle.send(req, list, list.length, port, ip, !!callback); if (err && callback) { // don't emit as error, dgram_legacy.js compatibility const ex = exceptionWithHostPort(err, 'send', address, port); process.nextTick(callback, ex); } } function afterSend(err, sent) { if (err) { err = exceptionWithHostPort(err, 'send', this.address, this.port); } else { err = null; } this.callback(err, sent); } Socket.prototype.close = function(callback) { if (typeof callback === 'function') this.on('close', callback); if (this._queue) { this._queue.push(this.close.bind(this)); return this; } this._healthCheck(); this._stopReceiving(); this._handle.close(); this._handle = null; process.nextTick(socketCloseNT, this); return this; }; function socketCloseNT(self) { self.emit('close'); } Socket.prototype.address = function() { this._healthCheck(); var out = {}; var err = this._handle.getsockname(out); if (err) { throw errnoException(err, 'getsockname'); } return out; }; Socket.prototype.setBroadcast = function(arg) { var err = this._handle.setBroadcast(arg ? 1 : 0); if (err) { throw errnoException(err, 'setBroadcast'); } }; Socket.prototype.setTTL = function(arg) { if (typeof arg !== 'number') { throw new TypeError('Argument must be a number'); } var err = this._handle.setTTL(arg); if (err) { throw errnoException(err, 'setTTL'); } return arg; }; Socket.prototype.setMulticastTTL = function(arg) { if (typeof arg !== 'number') { throw new TypeError('Argument must be a number'); } var err = this._handle.setMulticastTTL(arg); if (err) { throw errnoException(err, 'setMulticastTTL'); } return arg; }; Socket.prototype.setMulticastLoopback = function(arg) { var err = this._handle.setMulticastLoopback(arg ? 1 : 0); if (err) { throw errnoException(err, 'setMulticastLoopback'); } return arg; // 0.4 compatibility }; Socket.prototype.addMembership = function(multicastAddress, interfaceAddress) { this._healthCheck(); if (!multicastAddress) { throw new Error('multicast address must be specified'); } var err = this._handle.addMembership(multicastAddress, interfaceAddress); if (err) { throw errnoException(err, 'addMembership'); } }; Socket.prototype.dropMembership = function(multicastAddress, interfaceAddress) { this._healthCheck(); if (!multicastAddress) { throw new Error('multicast address must be specified'); } var err = this._handle.dropMembership(multicastAddress, interfaceAddress); if (err) { throw errnoException(err, 'dropMembership'); } }; Socket.prototype._healthCheck = function() { if (!this._handle) throw new Error('Not running'); // error message from dgram_legacy.js }; Socket.prototype._stopReceiving = function() { if (!this._receiving) return; this._handle.recvStop(); this._receiving = false; this.fd = null; // compatibility hack }; function onMessage(nread, handle, buf, rinfo) { var self = handle.owner; if (nread < 0) { return self.emit('error', errnoException(nread, 'recvmsg')); } rinfo.size = buf.length; // compatibility self.emit('message', buf, rinfo); } Socket.prototype.ref = function() { if (this._handle) this._handle.ref(); return this; }; Socket.prototype.unref = function() { if (this._handle) this._handle.unref(); return this; };