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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /devtools/server/socket/websocket-server.js | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'devtools/server/socket/websocket-server.js')
-rw-r--r-- | devtools/server/socket/websocket-server.js | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/devtools/server/socket/websocket-server.js b/devtools/server/socket/websocket-server.js new file mode 100644 index 0000000000..4236ec2921 --- /dev/null +++ b/devtools/server/socket/websocket-server.js @@ -0,0 +1,250 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +"use strict"; + +const { executeSoon } = require("resource://devtools/shared/DevToolsUtils.js"); +const { + delimitedRead, +} = require("resource://devtools/shared/transport/stream-utils.js"); +const CryptoHash = Components.Constructor( + "@mozilla.org/security/hash;1", + "nsICryptoHash", + "initWithString" +); +const threadManager = Cc["@mozilla.org/thread-manager;1"].getService(); + +// Limit the header size to put an upper bound on allocated memory +const HEADER_MAX_LEN = 8000; + +/** + * Read a line from async input stream and return promise that resolves to the line once + * it has been read. If the line is longer than HEADER_MAX_LEN, will throw error. + */ +function readLine(input) { + return new Promise((resolve, reject) => { + let line = ""; + const wait = () => { + input.asyncWait( + stream => { + try { + const amountToRead = HEADER_MAX_LEN - line.length; + line += delimitedRead(input, "\n", amountToRead); + + if (line.endsWith("\n")) { + resolve(line.trimRight()); + return; + } + + if (line.length >= HEADER_MAX_LEN) { + throw new Error( + `Failed to read HTTP header longer than ${HEADER_MAX_LEN} bytes` + ); + } + + wait(); + } catch (ex) { + reject(ex); + } + }, + 0, + 0, + threadManager.currentThread + ); + }; + + wait(); + }); +} + +/** + * Write a string of bytes to async output stream and return promise that resolves once + * all data has been written. Doesn't do any utf-16/utf-8 conversion - the string is + * treated as an array of bytes. + */ +function writeString(output, data) { + return new Promise((resolve, reject) => { + const wait = () => { + if (data.length === 0) { + resolve(); + return; + } + + output.asyncWait( + stream => { + try { + const written = output.write(data, data.length); + data = data.slice(written); + wait(); + } catch (ex) { + reject(ex); + } + }, + 0, + 0, + threadManager.currentThread + ); + }; + + wait(); + }); +} + +/** + * Read HTTP request from async input stream. + * @return Request line (string) and Map of header names and values. + */ +const readHttpRequest = async function (input) { + let requestLine = ""; + const headers = new Map(); + + while (true) { + const line = await readLine(input); + if (!line.length) { + break; + } + + if (!requestLine) { + requestLine = line; + } else { + const colon = line.indexOf(":"); + if (colon == -1) { + throw new Error(`Malformed HTTP header: ${line}`); + } + + const name = line.slice(0, colon).toLowerCase(); + const value = line.slice(colon + 1).trim(); + headers.set(name, value); + } + } + + return { requestLine, headers }; +}; + +/** + * Write HTTP response (array of strings) to async output stream. + */ +function writeHttpResponse(output, response) { + const responseString = response.join("\r\n") + "\r\n\r\n"; + return writeString(output, responseString); +} + +/** + * Process the WebSocket handshake headers and return the key to be sent in + * Sec-WebSocket-Accept response header. + */ +function processRequest({ requestLine, headers }) { + const [method, path] = requestLine.split(" "); + if (method !== "GET") { + throw new Error("The handshake request must use GET method"); + } + + if (path !== "/") { + throw new Error("The handshake request has unknown path"); + } + + const upgrade = headers.get("upgrade"); + if (!upgrade || upgrade !== "websocket") { + throw new Error("The handshake request has incorrect Upgrade header"); + } + + const connection = headers.get("connection"); + if ( + !connection || + !connection + .split(",") + .map(t => t.trim()) + .includes("Upgrade") + ) { + throw new Error("The handshake request has incorrect Connection header"); + } + + const version = headers.get("sec-websocket-version"); + if (!version || version !== "13") { + throw new Error( + "The handshake request must have Sec-WebSocket-Version: 13" + ); + } + + // Compute the accept key + const key = headers.get("sec-websocket-key"); + if (!key) { + throw new Error( + "The handshake request must have a Sec-WebSocket-Key header" + ); + } + + return { acceptKey: computeKey(key) }; +} + +function computeKey(key) { + const str = key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"; + + const data = Array.from(str, ch => ch.charCodeAt(0)); + const hash = new CryptoHash("sha1"); + hash.update(data, data.length); + return hash.finish(true); +} + +/** + * Perform the server part of a WebSocket opening handshake on an incoming connection. + */ +const serverHandshake = async function (input, output) { + // Read the request + const request = await readHttpRequest(input); + + try { + // Check and extract info from the request + const { acceptKey } = processRequest(request); + + // Send response headers + await writeHttpResponse(output, [ + "HTTP/1.1 101 Switching Protocols", + "Upgrade: websocket", + "Connection: Upgrade", + `Sec-WebSocket-Accept: ${acceptKey}`, + ]); + } catch (error) { + // Send error response in case of error + await writeHttpResponse(output, ["HTTP/1.1 400 Bad Request"]); + throw error; + } +}; + +/** + * Accept an incoming WebSocket server connection. + * Takes an established nsISocketTransport in the parameters. + * Performs the WebSocket handshake and waits for the WebSocket to open. + * Returns Promise with a WebSocket ready to send and receive messages. + */ +const accept = async function (transport, input, output) { + await serverHandshake(input, output); + + const transportProvider = { + setListener(upgradeListener) { + // The onTransportAvailable callback shouldn't be called synchronously. + executeSoon(() => { + upgradeListener.onTransportAvailable(transport, input, output); + }); + }, + }; + + return new Promise((resolve, reject) => { + const socket = WebSocket.createServerWebSocket( + null, + [], + transportProvider, + "" + ); + socket.addEventListener("close", () => { + input.close(); + output.close(); + }); + + socket.onopen = () => resolve(socket); + socket.onerror = err => reject(err); + }); +}; + +exports.accept = accept; |