Optional Tor support

src/lib/utils/tor.js

@@ -0,0 +1,79 @@
+const SocksProxyAgent = require("socks-proxy-agent")
+const {connect} = require("net");
+const constants = require("../constants")
+const {request} = require("./request")
+
+class TorManager {
+	/**
+	 * @param {import("@deadcanaries/granax/lib/controller")} tor
+	 * @param {number} port
+	 */
+	constructor(tor, port) {
+		this.tor = tor
+		this.port = port
+		this.agent = new SocksProxyAgent("socks5://localhost:"+this.port)
+	}
+
+	async request(url, test) {
+		let result = null
+		while (!result) {
+			const req = await request(url, {agent: this.agent}, {log: true, statusLine: "TOR"})
+			try {
+				result = await test(req)
+			} catch (e) {
+				await this.newCircuit()
+			}
+		}
+		return result
+	}
+
+	newCircuit() {
+		return new Promise(resolve => {
+			this.tor.cleanCircuits(() => resolve())
+		})
+	}
+}
+
+try {
+	var granax = require("@deadcanaries/granax")
+} catch (e) {}
+
+/** @type {Promise<TorManager>} */
+module.exports = new Promise(resolve => {
+	if (granax) {
+		/** @type {import("@deadcanaries/granax/lib/controller")} */
+		// @ts-ignore
+		let tor
+		if (constants.tor_password == null) {
+			// @ts-ignore
+			tor = new granax()
+		} else {
+			tor = new granax.TorController(connect(9051), {authOnConnect: false})
+			tor.authenticate(`"${constants.tor_password}"`, err => {
+				if (err) console.log("Tor auth error:", err)
+			})
+		}
+
+		console.log("Starting tor...")
+
+		tor.once("ready", () => {
+			tor.getInfo("net/listeners/socks", (err, result) => {
+				if (err) throw err
+				// result is string containing something like "127.0.0.1:36977"
+				// yes, the string contains double quotes!
+				const port = +result.match(/:(\d+)/)[1]
+				const torManager = new TorManager(tor, port)
+				console.log("Tor is ready, using SOCKS port "+port)
+				resolve(torManager)
+			})
+		})
+
+		tor.on("error", function() {
+			console.log("Tor error!")
+			console.log(...arguments)
+		})
+	} else {
+		console.log("Note: Tor functionality not installed. You may wish to run `npm install @deadcanaries/granax`. (78+ MB download required.)")
+		resolve(null)
+	}
+})