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Diffstat (limited to 'testing/xpcshell/node-ws/lib/permessage-deflate.js')
| -rw-r--r-- | testing/xpcshell/node-ws/lib/permessage-deflate.js | 511 |
1 files changed, 511 insertions, 0 deletions
diff --git a/testing/xpcshell/node-ws/lib/permessage-deflate.js b/testing/xpcshell/node-ws/lib/permessage-deflate.js new file mode 100644 index 0000000000..94603c98da --- /dev/null +++ b/testing/xpcshell/node-ws/lib/permessage-deflate.js @@ -0,0 +1,511 @@ +'use strict'; + +const zlib = require('zlib'); + +const bufferUtil = require('./buffer-util'); +const Limiter = require('./limiter'); +const { kStatusCode } = require('./constants'); + +const TRAILER = Buffer.from([0x00, 0x00, 0xff, 0xff]); +const kPerMessageDeflate = Symbol('permessage-deflate'); +const kTotalLength = Symbol('total-length'); +const kCallback = Symbol('callback'); +const kBuffers = Symbol('buffers'); +const kError = Symbol('error'); + +// +// We limit zlib concurrency, which prevents severe memory fragmentation +// as documented in https://github.com/nodejs/node/issues/8871#issuecomment-250915913 +// and https://github.com/websockets/ws/issues/1202 +// +// Intentionally global; it's the global thread pool that's an issue. +// +let zlibLimiter; + +/** + * permessage-deflate implementation. + */ +class PerMessageDeflate { + /** + * Creates a PerMessageDeflate instance. + * + * @param {Object} [options] Configuration options + * @param {(Boolean|Number)} [options.clientMaxWindowBits] Advertise support + * for, or request, a custom client window size + * @param {Boolean} [options.clientNoContextTakeover=false] Advertise/ + * acknowledge disabling of client context takeover + * @param {Number} [options.concurrencyLimit=10] The number of concurrent + * calls to zlib + * @param {(Boolean|Number)} [options.serverMaxWindowBits] Request/confirm the + * use of a custom server window size + * @param {Boolean} [options.serverNoContextTakeover=false] Request/accept + * disabling of server context takeover + * @param {Number} [options.threshold=1024] Size (in bytes) below which + * messages should not be compressed if context takeover is disabled + * @param {Object} [options.zlibDeflateOptions] Options to pass to zlib on + * deflate + * @param {Object} [options.zlibInflateOptions] Options to pass to zlib on + * inflate + * @param {Boolean} [isServer=false] Create the instance in either server or + * client mode + * @param {Number} [maxPayload=0] The maximum allowed message length + */ + constructor(options, isServer, maxPayload) { + this._maxPayload = maxPayload | 0; + this._options = options || {}; + this._threshold = + this._options.threshold !== undefined ? this._options.threshold : 1024; + this._isServer = !!isServer; + this._deflate = null; + this._inflate = null; + + this.params = null; + + if (!zlibLimiter) { + const concurrency = + this._options.concurrencyLimit !== undefined + ? this._options.concurrencyLimit + : 10; + zlibLimiter = new Limiter(concurrency); + } + } + + /** + * @type {String} + */ + static get extensionName() { + return 'permessage-deflate'; + } + + /** + * Create an extension negotiation offer. + * + * @return {Object} Extension parameters + * @public + */ + offer() { + const params = {}; + + if (this._options.serverNoContextTakeover) { + params.server_no_context_takeover = true; + } + if (this._options.clientNoContextTakeover) { + params.client_no_context_takeover = true; + } + if (this._options.serverMaxWindowBits) { + params.server_max_window_bits = this._options.serverMaxWindowBits; + } + if (this._options.clientMaxWindowBits) { + params.client_max_window_bits = this._options.clientMaxWindowBits; + } else if (this._options.clientMaxWindowBits == null) { + params.client_max_window_bits = true; + } + + return params; + } + + /** + * Accept an extension negotiation offer/response. + * + * @param {Array} configurations The extension negotiation offers/reponse + * @return {Object} Accepted configuration + * @public + */ + accept(configurations) { + configurations = this.normalizeParams(configurations); + + this.params = this._isServer + ? this.acceptAsServer(configurations) + : this.acceptAsClient(configurations); + + return this.params; + } + + /** + * Releases all resources used by the extension. + * + * @public + */ + cleanup() { + if (this._inflate) { + this._inflate.close(); + this._inflate = null; + } + + if (this._deflate) { + const callback = this._deflate[kCallback]; + + this._deflate.close(); + this._deflate = null; + + if (callback) { + callback( + new Error( + 'The deflate stream was closed while data was being processed' + ) + ); + } + } + } + + /** + * Accept an extension negotiation offer. + * + * @param {Array} offers The extension negotiation offers + * @return {Object} Accepted configuration + * @private + */ + acceptAsServer(offers) { + const opts = this._options; + const accepted = offers.find((params) => { + if ( + (opts.serverNoContextTakeover === false && + params.server_no_context_takeover) || + (params.server_max_window_bits && + (opts.serverMaxWindowBits === false || + (typeof opts.serverMaxWindowBits === 'number' && + opts.serverMaxWindowBits > params.server_max_window_bits))) || + (typeof opts.clientMaxWindowBits === 'number' && + !params.client_max_window_bits) + ) { + return false; + } + + return true; + }); + + if (!accepted) { + throw new Error('None of the extension offers can be accepted'); + } + + if (opts.serverNoContextTakeover) { + accepted.server_no_context_takeover = true; + } + if (opts.clientNoContextTakeover) { + accepted.client_no_context_takeover = true; + } + if (typeof opts.serverMaxWindowBits === 'number') { + accepted.server_max_window_bits = opts.serverMaxWindowBits; + } + if (typeof opts.clientMaxWindowBits === 'number') { + accepted.client_max_window_bits = opts.clientMaxWindowBits; + } else if ( + accepted.client_max_window_bits === true || + opts.clientMaxWindowBits === false + ) { + delete accepted.client_max_window_bits; + } + + return accepted; + } + + /** + * Accept the extension negotiation response. + * + * @param {Array} response The extension negotiation response + * @return {Object} Accepted configuration + * @private + */ + acceptAsClient(response) { + const params = response[0]; + + if ( + this._options.clientNoContextTakeover === false && + params.client_no_context_takeover + ) { + throw new Error('Unexpected parameter "client_no_context_takeover"'); + } + + if (!params.client_max_window_bits) { + if (typeof this._options.clientMaxWindowBits === 'number') { + params.client_max_window_bits = this._options.clientMaxWindowBits; + } + } else if ( + this._options.clientMaxWindowBits === false || + (typeof this._options.clientMaxWindowBits === 'number' && + params.client_max_window_bits > this._options.clientMaxWindowBits) + ) { + throw new Error( + 'Unexpected or invalid parameter "client_max_window_bits"' + ); + } + + return params; + } + + /** + * Normalize parameters. + * + * @param {Array} configurations The extension negotiation offers/reponse + * @return {Array} The offers/response with normalized parameters + * @private + */ + normalizeParams(configurations) { + configurations.forEach((params) => { + Object.keys(params).forEach((key) => { + let value = params[key]; + + if (value.length > 1) { + throw new Error(`Parameter "${key}" must have only a single value`); + } + + value = value[0]; + + if (key === 'client_max_window_bits') { + if (value !== true) { + const num = +value; + if (!Number.isInteger(num) || num < 8 || num > 15) { + throw new TypeError( + `Invalid value for parameter "${key}": ${value}` + ); + } + value = num; + } else if (!this._isServer) { + throw new TypeError( + `Invalid value for parameter "${key}": ${value}` + ); + } + } else if (key === 'server_max_window_bits') { + const num = +value; + if (!Number.isInteger(num) || num < 8 || num > 15) { + throw new TypeError( + `Invalid value for parameter "${key}": ${value}` + ); + } + value = num; + } else if ( + key === 'client_no_context_takeover' || + key === 'server_no_context_takeover' + ) { + if (value !== true) { + throw new TypeError( + `Invalid value for parameter "${key}": ${value}` + ); + } + } else { + throw new Error(`Unknown parameter "${key}"`); + } + + params[key] = value; + }); + }); + + return configurations; + } + + /** + * Decompress data. Concurrency limited. + * + * @param {Buffer} data Compressed data + * @param {Boolean} fin Specifies whether or not this is the last fragment + * @param {Function} callback Callback + * @public + */ + decompress(data, fin, callback) { + zlibLimiter.add((done) => { + this._decompress(data, fin, (err, result) => { + done(); + callback(err, result); + }); + }); + } + + /** + * Compress data. Concurrency limited. + * + * @param {(Buffer|String)} data Data to compress + * @param {Boolean} fin Specifies whether or not this is the last fragment + * @param {Function} callback Callback + * @public + */ + compress(data, fin, callback) { + zlibLimiter.add((done) => { + this._compress(data, fin, (err, result) => { + done(); + callback(err, result); + }); + }); + } + + /** + * Decompress data. + * + * @param {Buffer} data Compressed data + * @param {Boolean} fin Specifies whether or not this is the last fragment + * @param {Function} callback Callback + * @private + */ + _decompress(data, fin, callback) { + const endpoint = this._isServer ? 'client' : 'server'; + + if (!this._inflate) { + const key = `${endpoint}_max_window_bits`; + const windowBits = + typeof this.params[key] !== 'number' + ? zlib.Z_DEFAULT_WINDOWBITS + : this.params[key]; + + this._inflate = zlib.createInflateRaw({ + ...this._options.zlibInflateOptions, + windowBits + }); + this._inflate[kPerMessageDeflate] = this; + this._inflate[kTotalLength] = 0; + this._inflate[kBuffers] = []; + this._inflate.on('error', inflateOnError); + this._inflate.on('data', inflateOnData); + } + + this._inflate[kCallback] = callback; + + this._inflate.write(data); + if (fin) this._inflate.write(TRAILER); + + this._inflate.flush(() => { + const err = this._inflate[kError]; + + if (err) { + this._inflate.close(); + this._inflate = null; + callback(err); + return; + } + + const data = bufferUtil.concat( + this._inflate[kBuffers], + this._inflate[kTotalLength] + ); + + if (this._inflate._readableState.endEmitted) { + this._inflate.close(); + this._inflate = null; + } else { + this._inflate[kTotalLength] = 0; + this._inflate[kBuffers] = []; + + if (fin && this.params[`${endpoint}_no_context_takeover`]) { + this._inflate.reset(); + } + } + + callback(null, data); + }); + } + + /** + * Compress data. + * + * @param {(Buffer|String)} data Data to compress + * @param {Boolean} fin Specifies whether or not this is the last fragment + * @param {Function} callback Callback + * @private + */ + _compress(data, fin, callback) { + const endpoint = this._isServer ? 'server' : 'client'; + + if (!this._deflate) { + const key = `${endpoint}_max_window_bits`; + const windowBits = + typeof this.params[key] !== 'number' + ? zlib.Z_DEFAULT_WINDOWBITS + : this.params[key]; + + this._deflate = zlib.createDeflateRaw({ + ...this._options.zlibDeflateOptions, + windowBits + }); + + this._deflate[kTotalLength] = 0; + this._deflate[kBuffers] = []; + + this._deflate.on('data', deflateOnData); + } + + this._deflate[kCallback] = callback; + + this._deflate.write(data); + this._deflate.flush(zlib.Z_SYNC_FLUSH, () => { + if (!this._deflate) { + // + // The deflate stream was closed while data was being processed. + // + return; + } + + let data = bufferUtil.concat( + this._deflate[kBuffers], + this._deflate[kTotalLength] + ); + + if (fin) data = data.slice(0, data.length - 4); + + // + // Ensure that the callback will not be called again in + // `PerMessageDeflate#cleanup()`. + // + this._deflate[kCallback] = null; + + this._deflate[kTotalLength] = 0; + this._deflate[kBuffers] = []; + + if (fin && this.params[`${endpoint}_no_context_takeover`]) { + this._deflate.reset(); + } + + callback(null, data); + }); + } +} + +module.exports = PerMessageDeflate; + +/** + * The listener of the `zlib.DeflateRaw` stream `'data'` event. + * + * @param {Buffer} chunk A chunk of data + * @private + */ +function deflateOnData(chunk) { + this[kBuffers].push(chunk); + this[kTotalLength] += chunk.length; +} + +/** + * The listener of the `zlib.InflateRaw` stream `'data'` event. + * + * @param {Buffer} chunk A chunk of data + * @private + */ +function inflateOnData(chunk) { + this[kTotalLength] += chunk.length; + + if ( + this[kPerMessageDeflate]._maxPayload < 1 || + this[kTotalLength] <= this[kPerMessageDeflate]._maxPayload + ) { + this[kBuffers].push(chunk); + return; + } + + this[kError] = new RangeError('Max payload size exceeded'); + this[kError].code = 'WS_ERR_UNSUPPORTED_MESSAGE_LENGTH'; + this[kError][kStatusCode] = 1009; + this.removeListener('data', inflateOnData); + this.reset(); +} + +/** + * The listener of the `zlib.InflateRaw` stream `'error'` event. + * + * @param {Error} err The emitted error + * @private + */ +function inflateOnError(err) { + // + // There is no need to call `Zlib#close()` as the handle is automatically + // closed when an error is emitted. + // + this[kPerMessageDeflate]._inflate = null; + err[kStatusCode] = 1007; + this[kCallback](err); +} |