XMPP connection request

lib/api-functions.ts

@@ -29,12 +29,16 @@ import {
 import {
   httpConnectionRequest,
   udpConnectionRequest,
+  xmppConnectionRequest,
 } from "./connection-request.ts";
 import { Expression, Task } from "./types.ts";
 import { evaluate } from "./common/expression/util.ts";
 import { hashPassword } from "./auth.ts";
 import { flattenDevice } from "./ui/db.ts";
 import { ResourceLockedError } from "./common/errors.ts";
+import * as config from "../lib/config.ts";
+
+const XMPP_CONFIGURED = !!config.get("XMPP_JID");
 
 export async function connectionRequest(
   deviceId: string,
@@ -46,7 +50,12 @@ export async function connectionRequest(
     device = flattenDevice(res);
   }
 
-  let connectionRequestUrl, udpConnectionRequestAddress, username, password;
+  let connectionRequestUrl,
+    udpConnectionRequestAddress,
+    stunEnable,
+    connReqJabberId,
+    username,
+    password;
 
   if (device["InternetGatewayDevice.ManagementServer.ConnectionRequestURL"]) {
     connectionRequestUrl = (device[
@@ -57,6 +66,12 @@ export async function connectionRequest(
         "InternetGatewayDevice.ManagementServer.UDPConnectionRequestAddress"
       ] || {}
     ).value || [""])[0];
+    stunEnable = ((
+      device["InternetGatewayDevice.ManagementServer.STUNEnable"] || {}
+    ).value || [""])[0];
+    connReqJabberId = ((
+      device["InternetGatewayDevice.ManagementServer.ConnReqJabberID"] || {}
+    ).value || [""])[0];
     username = ((
       device[
         "InternetGatewayDevice.ManagementServer.ConnectionRequestUsername"
@@ -74,6 +89,10 @@ export async function connectionRequest(
     udpConnectionRequestAddress = ((
       device["Device.ManagementServer.UDPConnectionRequestAddress"] || {}
     ).value || [""])[0];
+    stunEnable = ((device["Device.ManagementServer.STUNEnable"] || {})
+      .value || [""])[0];
+    connReqJabberId = ((device["Device.ManagementServer.ConnReqJabberID"] || {})
+      .value || [""])[0];
     username = ((
       device["Device.ManagementServer.ConnectionRequestUsername"] || {}
     ).value || [""])[0];
@@ -148,7 +167,7 @@ export async function connectionRequest(
   const debug = !!getConfig(snapshot, "cwmp.debug", {}, now, evalCallback);
 
   let udpProm = Promise.resolve(false);
-  if (udpConnectionRequestAddress) {
+  if (udpConnectionRequestAddress && +stunEnable) {
     try {
       const u = new URL("udp://" + udpConnectionRequestAddress);
       udpProm = udpConnectionRequest(
@@ -167,14 +186,26 @@ export async function connectionRequest(
     }
   }
 
-  const status = await httpConnectionRequest(
+  let status;
-    connectionRequestUrl,
+
-    authExp,
+  if (connReqJabberId && XMPP_CONFIGURED) {
-    CONNECTION_REQUEST_ALLOW_BASIC_AUTH,
+    status = await xmppConnectionRequest(
-    CONNECTION_REQUEST_TIMEOUT,
+      connReqJabberId,
-    debug,
+      authExp,
-    deviceId,
+      CONNECTION_REQUEST_TIMEOUT,
-  );
+      debug,
+      deviceId,
+    );
+  } else {
+    status = await httpConnectionRequest(
+      connectionRequestUrl,
+      authExp,
+      CONNECTION_REQUEST_ALLOW_BASIC_AUTH,
+      CONNECTION_REQUEST_TIMEOUT,
+      debug,
+      deviceId,
+    );
+  }
 
   if (await udpProm) return "";
 

lib/config.ts

@@ -82,6 +82,9 @@ const options = {
 
   // Should probably never be changed
   DEVICE_ONLINE_THRESHOLD: { type: "int", default: 4000 },
+
+  XMPP_JID: { type: "string", default: "" },
+  XMPP_PASSWORD: { type: "string", default: "" },
 };
 
 const allConfig: { [name: string]: string | number } = {};

lib/connection-request.ts

@@ -6,6 +6,10 @@ import { Expression } from "./types.ts";
 import * as auth from "./auth.ts";
 import * as extensions from "./extensions.ts";
 import * as debug from "./debug.ts";
+import XmppClient from "./xmpp-client.ts";
+import * as config from "../lib/config.ts";
+import { encodeEntities, parseAttrs, Element } from "./xml-parser.ts";
+import * as logger from "../lib/logger.ts";
 
 async function extractAuth(
   exp: Expression,
@@ -217,3 +221,84 @@ export async function udpConnectionRequest(
   }
   client.close();
 }
+
+const XMPP_JID = config.get("XMPP_JID") as string;
+const XMPP_PASSWORD = config.get("XMPP_PASSWORD") as string;
+const XMPP_RESOURCE = crypto.randomBytes(8).toString("hex");
+
+let xmppClient: XmppClient;
+
+function xmppClientOnError(err: Error): void {
+  xmppClient = null;
+  logger.error({
+    message: "XMPP exception",
+    exception: err,
+    pid: process.pid,
+  });
+}
+
+function xmppClientOnClose(): void {
+  xmppClient = null;
+}
+
+export async function xmppConnectionRequest(
+  jid: string,
+  authExp: Expression,
+  timeout: number,
+  _debug: boolean,
+  deviceId: string,
+): Promise<string> {
+  if (!xmppClient) {
+    const [host, username] = XMPP_JID.split("@").reverse();
+    xmppClient = await XmppClient.connect({
+      host,
+      username,
+      resource: XMPP_RESOURCE,
+      password: XMPP_PASSWORD,
+      timeout: 120000,
+    });
+    xmppClient.on("error", xmppClientOnError);
+    xmppClient.on("close", xmppClientOnClose);
+    xmppClient.unref();
+  }
+
+  let username: string;
+  let password: string;
+
+  [username, password, authExp] = await extractAuth(authExp, null);
+  while (username != null && password != null) {
+    const msg = `<connectionRequest xmlns="urn:broadband-forum-org:cwmp:xmppConnReq-1-0"><username>${encodeEntities(
+      username,
+    )}</username><password>${encodeEntities(
+      password,
+    )}</password></connectionRequest>`;
+    let res: Element, rawRes: string, rawReq: string;
+    try {
+      ({ res, rawRes, rawReq } = await xmppClient.sendIqStanza(
+        XMPP_JID,
+        jid,
+        "get",
+        msg,
+        timeout,
+      ));
+    } catch (err) {
+      return err.message;
+    }
+    if (_debug) {
+      debug.outgoingXmppStanza(deviceId, rawReq);
+      debug.incomingXmppStanza(deviceId, rawRes);
+    }
+    const attrs = parseAttrs(res.attrs);
+    const type = attrs.find((a) => a.name === "type");
+    if (type && type.value === "result") return "";
+    const error = res.children.find((c) => c.name === "error");
+    if (!error || !error.children[0])
+      return "Unexpected XMPP connection request response";
+    if (error.children[0].name === "service-unavailable")
+      return "Device is offline";
+    if (error.children[0].name !== "not-authorized")
+      return "Unexpected XMPP connection request response";
+    [username, password, authExp] = await extractAuth(authExp, null);
+  }
+  return "Incorrect connection request credentials";
+}

lib/debug.ts

@@ -200,3 +200,37 @@ export function clientError(remoteAddress: string, err: Error): void {
     appendFileSync(DEBUG_FILE, JSON.stringify(msg) + "\n");
   else throw new Error(`Unrecognized DEBUG_FORMAT option`);
 }
+
+export function outgoingXmppStanza(deviceId: string, body: string): void {
+  if (!DEBUG_FILE) return;
+  const now = new Date();
+  const msg = {
+    event: "outgoing XMPP stanza",
+    timestamp: now,
+    deviceId: deviceId,
+    body: body,
+  };
+
+  if (DEBUG_FORMAT === "yaml")
+    appendFileSync(DEBUG_FILE, "---\n" + stringify(msg));
+  else if (DEBUG_FORMAT === "json")
+    appendFileSync(DEBUG_FILE, JSON.stringify(msg) + "\n");
+  else throw new Error(`Unrecognized DEBUG_FORMAT option`);
+}
+
+export function incomingXmppStanza(deviceId: string, body: string): void {
+  if (!DEBUG_FILE) return;
+  const now = new Date();
+  const msg = {
+    event: "incoming XMPP stanza",
+    timestamp: now,
+    deviceId: deviceId,
+    body: body,
+  };
+
+  if (DEBUG_FORMAT === "yaml")
+    appendFileSync(DEBUG_FILE, "---\n" + stringify(msg));
+  else if (DEBUG_FORMAT === "json")
+    appendFileSync(DEBUG_FILE, JSON.stringify(msg) + "\n");
+  else throw new Error(`Unrecognized DEBUG_FORMAT option`);
+}

lib/xmpp-client.ts

@@ -0,0 +1,466 @@
+import * as net from "node:net";
+import * as tls from "node:tls";
+import { EventEmitter } from "node:events";
+import { createHash, createHmac, randomBytes } from "node:crypto";
+import { parseXml, Element, parseAttrs } from "./xml-parser.ts";
+
+function encodeBase64(str: string): string {
+  return Buffer.from(str).toString("base64");
+}
+
+function decodeBase64(str: string): string {
+  return Buffer.from(str, "base64").toString();
+}
+
+function detectStreamTag(data: string): number {
+  const i1 = data.indexOf("<stream:stream");
+  if (i1 < 0) throw new Error("Cannot detect opening stream tag");
+  const i2 = data.indexOf(">", i1);
+  if (i2 < 0) throw new Error("Cannot detect opening stream tag");
+  return i2 + 1;
+}
+
+function xmppStream<T>(
+  socket: net.Socket,
+  callback: Generator<void, T, Element>,
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const onError = (err: Error): void => {
+      socket.removeListener("error", onError);
+      reject(err);
+    };
+    socket.on("error", onError);
+
+    const onData = (chunk: Buffer): void => {
+      try {
+        const str = chunk.toString("utf8");
+        const xml = parseXml(str);
+        const { value, done } = callback.next(xml.children[0]);
+        if (done) {
+          socket.removeListener("error", onError);
+          socket.removeListener("data", onData);
+          resolve(value as T);
+        }
+      } catch (err) {
+        socket.removeListener("error", onError);
+        socket.removeListener("data", onData);
+        reject(err);
+      }
+    };
+
+    socket.once("data", (chunk: Buffer) => {
+      try {
+        const str = chunk.toString("utf8");
+        const i = detectStreamTag(str);
+        const streamTagStr = str.slice(0, i);
+        const xml = parseXml(streamTagStr + "</stream:stream>");
+        callback.next(xml.children[0]);
+        chunk = chunk.slice(Buffer.byteLength(streamTagStr));
+        if (chunk.length) onData(chunk);
+        socket.on("data", onData);
+      } catch (err) {
+        socket.removeListener("error", onError);
+        socket.removeListener("data", onData);
+        reject(err);
+      }
+    });
+
+    try {
+      callback.next();
+    } catch (err) {
+      socket.removeListener("error", onError);
+      socket.removeListener("data", onData);
+      reject(err);
+    }
+  });
+}
+
+const INT_1 = Buffer.from([0, 0, 0, 1]);
+const saltedPasswordCache = {
+  password: "",
+  iterationCount: 0,
+  saltBase64: "",
+  salted: Buffer.allocUnsafe(0),
+};
+
+function saltPassword(
+  password: string,
+  saltBase64: string,
+  iteractionCount: number,
+): Buffer {
+  if (
+    password === saltedPasswordCache.password &&
+    saltBase64 === saltedPasswordCache.saltBase64 &&
+    iteractionCount === saltedPasswordCache.iterationCount
+  )
+    return saltedPasswordCache.salted;
+
+  const hi = createHmac("sha1", password)
+    .update(Buffer.concat([Buffer.from(saltBase64, "base64"), INT_1]))
+    .digest();
+  let hi2: Buffer = hi;
+  for (let i = 1; i < iteractionCount; ++i) {
+    hi2 = createHmac("sha1", password).update(hi2).digest();
+    for (const [j, b] of hi2.entries()) hi[j] ^= b;
+  }
+
+  saltedPasswordCache.saltBase64 = saltBase64;
+  saltedPasswordCache.password = password;
+  saltedPasswordCache.iterationCount = iteractionCount;
+  saltedPasswordCache.salted = hi;
+
+  return hi;
+}
+
+function* loginPlain(
+  socket: net.Socket,
+  username: string,
+  password: string,
+): Generator<void, void, Element> {
+  socket.write(
+    `<auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl" mechanism="PLAIN">${encodeBase64(
+      `\x00${username}\x00${password}`,
+    )}</auth>`,
+  );
+  const res1 = yield;
+
+  if (
+    res1.name === "failure" &&
+    res1.children.some((c) => c.name === "not-authorized")
+  )
+    throw new Error("Not authorized");
+
+  if (res1.name !== "success")
+    throw new Error(`Unexpected response ${res1.name}`);
+}
+
+function* loginScram(
+  socket: net.Socket,
+  username: string,
+  password: string,
+): Generator<void, void, Element> {
+  const cnonce = randomBytes(8).toString("base64");
+  const gs2Header = "n,,";
+  const clientFirstMessageBare = `n=${username},r=${cnonce}`;
+  const clientFirstMessage = gs2Header + clientFirstMessageBare;
+  socket.write(
+    `<auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl" mechanism="SCRAM-SHA-1">${encodeBase64(
+      clientFirstMessage,
+    )}</auth>`,
+  );
+  const res1 = yield;
+  if (res1.name !== "challenge")
+    throw new Error(`Unexpected element ${res1.name}`);
+  const serverFirstMessage = decodeBase64(res1.text);
+
+  let iterationCount: number;
+  let saltBase64: string;
+  let nonce: string;
+  for (const s of serverFirstMessage.split(",")) {
+    if (s.startsWith("i=")) iterationCount = parseInt(s.slice(2));
+    else if (s.startsWith("s=")) saltBase64 = s.slice(2);
+    else if (s.startsWith("r=")) nonce = s.slice(2);
+  }
+  if (iterationCount == null || isNaN(iterationCount))
+    throw new Error("Invalid iteration count");
+  if (saltBase64 == null) throw new Error("Missing salt");
+  if (nonce == null) throw new Error("Missing nonce");
+
+  const saltedPassword = saltPassword(password, saltBase64, iterationCount);
+  const clientKey = createHmac("sha1", saltedPassword)
+    .update("Client Key")
+    .digest();
+  const storedKey = createHash("sha1").update(clientKey).digest();
+
+  const clientFinalMessageWithoutProof = `c=${encodeBase64(
+    gs2Header,
+  )},r=${nonce}`;
+  const authMessage = `${clientFirstMessageBare},${serverFirstMessage},${clientFinalMessageWithoutProof}`;
+  const clientSignature = createHmac("sha1", storedKey)
+    .update(authMessage)
+    .digest();
+
+  const clientProof = Buffer.from(clientKey);
+  for (const [i, b] of clientSignature.entries()) clientProof[i] ^= b;
+
+  const clientFinalMessage = `${clientFinalMessageWithoutProof},p=${clientProof.toString(
+    "base64",
+  )}`;
+  socket.write(
+    `<response xmlns="urn:ietf:params:xml:ns:xmpp-sasl">${encodeBase64(
+      clientFinalMessage,
+    )}</response>`,
+  );
+  const res2 = yield;
+
+  if (
+    res2.name === "failure" &&
+    res2.children.some((c) => c.name === "not-authorized")
+  )
+    throw new Error("Not authorized");
+
+  if (res2.name !== "success")
+    throw new Error(`Unexpected response ${res2.name}`);
+
+  const serverKey = createHmac("sha1", saltedPassword)
+    .update("Server Key")
+    .digest();
+  const serverSignature = createHmac("sha1", serverKey)
+    .update(authMessage)
+    .digest("base64");
+
+  if (!decodeBase64(res2.text).endsWith(serverSignature))
+    throw new Error("Invalid server signature");
+}
+
+function* starttls(socket: net.Socket): Generator<void, void, Element> {
+  socket.write("<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'/>");
+  const res1 = yield;
+  if (res1.name !== "proceed") throw new Error("Failed to initiate STARTTLS");
+}
+
+function* bind(
+  socket: net.Socket,
+  resource: string,
+): Generator<void, void, Element> {
+  const id = randomBytes(8).toString("base64");
+  socket.write(
+    `<iq id='${id}' type='set'><bind xmlns='urn:ietf:params:xml:ns:xmpp-bind'><resource>${resource}</resource></bind></iq>`,
+  );
+  const res1 = yield;
+  if (res1.name !== "iq") throw new Error(`Unexpected element ${res1.name}`);
+  const attrs1 = parseAttrs(res1.attrs);
+  const idAttr = attrs1.find((a) => a.name === "id");
+  if (!idAttr || idAttr.value !== id) throw new Error("Invalid ID");
+  const typeAttr = attrs1.find((a) => a.name === "type");
+  if (!typeAttr) throw new Error("Missing type attribute");
+  if (typeAttr.value !== "result") throw new Error("Cannot bind to resource");
+}
+
+const STATUS_RESTART_STREAM = 1;
+const STATUS_STARTTLS = 2;
+
+function* init(
+  socket: net.Socket,
+  host: string,
+  username: string,
+  password: string,
+  resource: string,
+): Generator<void, number, Element> {
+  socket.write(
+    `<?xml version='1.0'?><stream:stream from='${username}@${host}' to='${host}' version='1.0' xml:lang='en' xmlns='jabber:client' xmlns:stream='http://etherx.jabber.org/streams'>`,
+  );
+  const open = yield;
+  if (open.name !== "stream:stream")
+    throw new Error(`Unexpected element ${open.name}`);
+  const features = yield;
+  if (features.name !== "stream:features")
+    throw new Error(`Unexpected element ${features.name}`);
+  for (const feature of features.children) {
+    if (feature.name === "starttls") {
+      if (feature.children.some((c) => c.name === "required")) {
+        yield* starttls(socket);
+        return STATUS_STARTTLS;
+      }
+    } else if (feature.name === "mechanisms") {
+      const mechanisms: Set<string> = new Set(
+        feature.children.map((c) => c.text),
+      );
+      if (mechanisms.has("PLAIN")) {
+        yield* loginPlain(socket, username, password);
+        return STATUS_RESTART_STREAM;
+      } else if (mechanisms.has("SCRAM-SHA-1")) {
+        yield* loginScram(socket, username, password);
+        return STATUS_RESTART_STREAM;
+      } else {
+        throw new Error("No supported SASL method");
+      }
+    } else if (feature.name === "bind") {
+      yield* bind(socket, resource);
+      return 0;
+    }
+  }
+  return 0;
+}
+
+function upgradeTls(socket: net.Socket, host: string): Promise<tls.TLSSocket> {
+  return new Promise((resolve, reject) => {
+    socket.on("error", reject);
+    const newSocket = tls.connect({ socket, host }, () => {
+      socket.removeListener("error", reject);
+      resolve(newSocket);
+    });
+  });
+}
+
+interface XmppClientOptions {
+  host: string;
+  port?: number;
+  username?: string;
+  password?: string;
+  resource?: string;
+  timeout?: number;
+}
+
+export default class XmppClient extends EventEmitter {
+  private _socket: net.Socket;
+  private _host: string;
+  private _username: string;
+  private _resource: string;
+  private _iqStanzaCallbacks: Map<
+    string,
+    (err: Error, r?: { rawRes: string; res: Element }) => void
+  >;
+
+  private constructor() {
+    super();
+    this._socket = null;
+    this._host = null;
+    this._username = null;
+    this._resource = null;
+    this._iqStanzaCallbacks = new Map();
+  }
+
+  static connect(opts: XmppClientOptions): Promise<XmppClient> {
+    return new Promise((resolve, reject) => {
+      let socket = new net.Socket();
+      socket.on("error", reject);
+
+      socket.connect(
+        opts.port || 5222,
+        opts.host,
+        void async function () {
+          socket.removeListener("error", reject);
+          try {
+            let status = 1;
+            while (status) {
+              if (status === STATUS_STARTTLS)
+                socket = await upgradeTls(socket, opts.host);
+              status = await xmppStream(
+                socket,
+                init(
+                  socket,
+                  opts.host,
+                  opts.username,
+                  opts.password,
+                  opts.resource,
+                ),
+              );
+            }
+
+            const client = new XmppClient();
+            client._socket = socket;
+            client._host = opts.host;
+            client._username = opts.username;
+            client._resource = opts.resource;
+            socket.on("data", client._onData.bind(client));
+            socket.on("error", client._onError.bind(client));
+            if (opts.timeout)
+              socket.setTimeout(opts.timeout, client.close.bind(client));
+            resolve(client);
+          } catch (err) {
+            socket.destroy();
+            reject(err);
+          }
+        },
+      );
+    });
+  }
+
+  close(): void {
+    this._socket.end("</stream:stream>");
+    this._socket.removeAllListeners("data");
+    this._socket.removeAllListeners("error");
+    this.emit("close");
+  }
+
+  ref(): void {
+    this._socket.ref();
+  }
+
+  unref(): void {
+    this._socket.unref();
+  }
+
+  get host(): string {
+    return this._host;
+  }
+
+  get username(): string {
+    return this._username;
+  }
+
+  get resource(): string {
+    return this._resource;
+  }
+
+  private _onData(chunk: Buffer): void {
+    try {
+      let close = false;
+      let str = chunk.toString("utf8");
+      if (str.endsWith("</stream:stream>")) {
+        str = str.slice(0, -16);
+        close = true;
+      }
+      const xml = parseXml(str);
+      const idx = xml.children.map((c) => c.bodyIndex);
+      for (const [i, c] of xml.children.entries()) {
+        const s = str.slice(idx[i], idx[i + 1]);
+        if (c.name === "iq") {
+          const attrs = parseAttrs(c.attrs);
+          const id = attrs.find((a) => a.name === "id");
+          if (id) {
+            const cb = this._iqStanzaCallbacks.get(id.value);
+            if (cb) cb(null, { rawRes: s, res: c });
+          }
+        }
+        this.emit("stanza", c, s);
+      }
+      if (close) {
+        this._socket.removeAllListeners("data");
+        this._socket.removeAllListeners("error");
+        this.emit("close");
+      }
+    } catch (err) {
+      this._socket.removeAllListeners("data");
+      this._socket.removeAllListeners("error");
+      this.emit("error", err);
+    }
+  }
+
+  private _onError(err: Error): void {
+    this._socket.end();
+    this.emit("error", err);
+    for (const cb of this._iqStanzaCallbacks.values()) cb(err);
+  }
+
+  send(msg: string): void {
+    this._socket.write(msg);
+  }
+
+  sendIqStanza(
+    from: string,
+    to: string,
+    type: string,
+    body: string,
+    timeout = 3000,
+  ): Promise<{ rawReq: string; rawRes: string; res: Element }> {
+    return new Promise((resolve, reject) => {
+      const id = randomBytes(8).toString("base64");
+      const rawReq = `<iq from="${from}" to="${to}" id="${id}" type="${type}">${body}</iq>`;
+      this.send(rawReq);
+      const t = setTimeout(() => {
+        this._iqStanzaCallbacks.delete(id);
+        reject(
+          new Error("Did not receive IQ stanza response in a timely manner"),
+        );
+      }, timeout);
+      this._iqStanzaCallbacks.set(id, (err, r) => {
+        this._iqStanzaCallbacks.delete(id);
+        clearTimeout(t);
+        if (err) reject(err);
+        else resolve(Object.assign(r, { rawReq }));
+      });
+    });
+  }
+}