Bump dependencies, add support for v3.3 firmware (#216)

* Update dependency coveralls to v3.0.4 (#206) * Update dependency ava to v2.1.0 (#211) * Update dependency documentation to v11.0.1 (#213) * Update dependency delay to v4.3.0 (#212) * Protocol 3.3 and encrypted discovery (#214) * Add check for set resolver * Don't emit event on set ACK * Don't emit event on set ACK * Hacked in support for protocol 3.3 and new UDP broadcast * MessageParser.decode now attempts to parse JSON after decryption Cipher.decrypt now always outputs a string, as MessageParser handles JSON parsing Updated cipher tests to account for this API change Tests now pass * Rollback cipher changes for now -- saving breaking changes for v6.0.0 Minor version bump to v5.1.0 as a result of the added protocol support * Fixed 3.1 producing a buffer on decryption failure Fixed 3.3 crc being taken before the payload is written * Removed debug used during testing * Removed redundant try catch block, as it throws the errors it catches * Moved some shared code from encode31() and encode33() to shared code path in encode() * Updated tests for improved coverage, including 3.3 protocol code paths * Refactored out encode31 and encode33 entirely as their differences could be contained to payload treatment * Ensure that version is a string Switched constructor to terse defaults pattern * Moved UDP key to its own file Added note about using protocol 3.3 without find()
codetheweb · Jun 16, 2019 · 94f24f1 · 94f24f1
1 parent 2fb72e8
commit 94f24f1
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diff --git a/README.md b/README.md
@@ -97,6 +97,7 @@ const device = new TuyAPI({
 ## 📝 Notes
 - Only one TCP connection can be in use with a device at once. If using this, do not have the app on your phone open.
 - Some devices ship with older firmware that may not work with `tuyapi`.  If you're experiencing issues, please try updating the device's firmware in the official app.
+- Newer firmware may use protocol 3.3. If you are not using `find()`, you will need to manually pass `version: 3.3` to the constructor.
 
 
 ## 📓 Documentation

diff --git a/index.js b/index.js
@@ -497,66 +497,88 @@ class TuyaDevice extends EventEmitter {
       return Promise.resolve(true);
     }
 
-    // Create new listener
+    // Create new listeners
     const listener = dgram.createSocket({type: 'udp4', reuseAddr: true});
     listener.bind(6666);
 
-    debug(`Finding missing IP ${this.device.ip} or ID ${this.device.id}`);
+    const listenerEncrypted = dgram.createSocket({type: 'udp4', reuseAddr: true});
+    listenerEncrypted.bind(6667);
 
-    // Find IP for device
-    return pTimeout(new Promise((resolve, reject) => { // Timeout
-      listener.on('message', message => {
-        debug('Received UDP message.');
+    const broadcastHandler = (resolve, reject) => message => {
+      debug('Received UDP message.');
 
-        let dataRes;
-        try {
-          dataRes = this.device.parser.parse(message)[0];
-        } catch (error) {
-          debug(error);
-          reject(error);
-        }
+      let dataRes;
+      try {
+        dataRes = this.device.parser.parse(message)[0];
+      } catch (error) {
+        debug(error);
+        reject(error);
+      }
 
-        debug('UDP data:');
-        debug(dataRes);
+      debug('UDP data:');
+      debug(dataRes);
 
-        const thisID = dataRes.payload.gwId;
-        const thisIP = dataRes.payload.ip;
+      const thisID = dataRes.payload.gwId;
+      const thisIP = dataRes.payload.ip;
 
-        // Add to array if it doesn't exist
-        if (!this.foundDevices.some(e => (e.id === thisID && e.ip === thisIP))) {
-          this.foundDevices.push({id: thisID, ip: thisIP});
-        }
+      // Add to array if it doesn't exist
+      if (!this.foundDevices.some(e => (e.id === thisID && e.ip === thisIP))) {
+        this.foundDevices.push({id: thisID, ip: thisIP});
+      }
 
-        if (!all &&
-            (this.device.id === thisID || this.device.ip === thisIP) &&
-            dataRes.payload) {
-          // Add IP
-          this.device.ip = dataRes.payload.ip;
+      if (!all &&
+          (this.device.id === thisID || this.device.ip === thisIP) &&
+          dataRes.payload) {
+        // Add IP
+        this.device.ip = dataRes.payload.ip;
 
-          // Add ID and gwID
-          this.device.id = dataRes.payload.gwId;
-          this.device.gwID = dataRes.payload.gwId;
+        // Add ID and gwID
+        this.device.id = dataRes.payload.gwId;
+        this.device.gwID = dataRes.payload.gwId;
 
-          // Change product key if neccessary
-          this.device.productKey = dataRes.payload.productKey;
+        // Change product key if neccessary
+        this.device.productKey = dataRes.payload.productKey;
 
-          // Change protocol version if necessary
+        // Change protocol version if necessary
+        if (this.device.version !== dataRes.payload.version) {
           this.device.version = dataRes.payload.version;
 
-          // Cleanup
-          listener.close();
-          listener.removeAllListeners();
-          resolve(true);
+          // Update the parser
+          this.device.parser = new MessageParser({
+            key: this.device.key,
+            version: this.device.version});
         }
-      });
+
+        // Cleanup
+        listener.close();
+        listener.removeAllListeners();
+        listenerEncrypted.close();
+        listenerEncrypted.removeAllListeners();
+        resolve(true);
+      }
+    };
+
+    debug(`Finding missing IP ${this.device.ip} or ID ${this.device.id}`);
+
+    // Find IP for device
+    return pTimeout(new Promise((resolve, reject) => { // Timeout
+      listener.on('message', broadcastHandler(resolve, reject));
 
       listener.on('error', err => {
         reject(err);
       });
+
+      listenerEncrypted.on('message', broadcastHandler(resolve, reject));
+
+      listenerEncrypted.on('error', err => {
+        reject(err);
+      });
     }), timeout * 1000, () => {
       // Have to do this so we exit cleanly
       listener.close();
       listener.removeAllListeners();
+      listenerEncrypted.close();
+      listenerEncrypted.removeAllListeners();
 
       // Return all devices
       if (all) {
@@ -577,18 +599,14 @@ class TuyaDevice extends EventEmitter {
   async toggle(property = '1') {
     property = property.toString();
 
-    try {
-      // Get status
-      const status = await this.get({dps: property});
+    // Get status
+    const status = await this.get({dps: property});
 
-      // Set to opposite
-      await this.set({set: !status, dps: property});
+    // Set to opposite
+    await this.set({set: !status, dps: property});
 
-      // Return new status
-      return await this.get({dps: property});
-    } catch (error) {
-      throw error;
-    }
+    // Return new status
+    return this.get({dps: property});
   }
 }
 

diff --git a/lib/cipher.js b/lib/cipher.js
@@ -1,4 +1,7 @@
 const crypto = require('crypto');
+const config = require('./config');
+
+const UDP_KEY = crypto.createHash('md5').update(config.udpKey, 'utf8').digest();
 
 /**
 * Low-level class for encrypting and decrypting payloads.
@@ -49,19 +52,35 @@ class TuyaCipher {
     let format = 'buffer';
 
     if (data.indexOf(this.version) === 0) {
-      // Data has version number and is encoded in base64
-
-      // Remove prefix of version number and MD5 hash
-      data = data.slice(19);
+      if (this.version === '3.3') {
+        // Remove 3.3 header
+        data = data.slice(15);
+      } else {
+        // Data has version number and is encoded in base64
 
-      // Decode incoming data as base64
-      format = 'base64';
+        // Remove prefix of version number and MD5 hash
+        data = data.slice(19).toString();
+        // Decode incoming data as base64
+        format = 'base64';
+      }
     }
 
     // Decrypt data
-    const decipher = crypto.createDecipheriv('aes-128-ecb', this.key, '');
-    let result = decipher.update(data, format, 'utf8');
-    result += decipher.final('utf8');
+    let result;
+    try {
+      const decipher = crypto.createDecipheriv('aes-128-ecb', this.key, '');
+      result = decipher.update(data, format, 'utf8');
+      result += decipher.final('utf8');
+    } catch (error) {
+      // Try the universal key, in case it's a new UDP message format
+      try {
+        const decipher = crypto.createDecipheriv('aes-128-ecb', UDP_KEY, '');
+        result = decipher.update(data, format, 'utf8');
+        result += decipher.final('utf8');
+      } catch (error) {
+        throw new Error('Decrypt failed');
+      }
+    }
 
     // Try to parse data as JSON,
     // otherwise return as string.

diff --git a/lib/config.json b/lib/config.json
@@ -0,0 +1 @@
+{"udpKey":"yGAdlopoPVldABfn"}
diff --git a/lib/message-parser.js b/lib/message-parser.js
@@ -66,19 +66,18 @@ const CommandType = {
 * const parser = new MessageParser({key: 'xxxxxxxxxxxxxxxx', version: 3.1})
 */
 class MessageParser {
-  constructor(options) {
-    // Defaults
-    options = options ? options : {};
-    options.version = options.version ? options.version : '3.1';
-
-    if (options.key && options.key.length !== 16) {
-      throw new TypeError('Incorrect key format');
-    }
+  constructor({key, version = 3.1} = {}) {
+    // Ensure the version is a string
+    version = version.toString();
+    this.version = version;
+
+    if (key) {
+      if (key.length !== 16) {
+        throw new TypeError('Incorrect key format');
+      }
 
-    if (options.key && options.version) {
-      this.cipher = new Cipher(options);
-      this.key = options.key;
-      this.version = options.version;
+      // Create a Cipher if we have a valid key
+      this.cipher = new Cipher({key, version});
     }
   }
 
@@ -125,12 +124,12 @@ class MessageParser {
     // Get sequence number
     const sequenceN = buffer.readUInt32BE(4);
 
+    // Get command byte
+    const commandByte = buffer.readUInt32BE(8);
+
     // Get payload size
     const payloadSize = buffer.readUInt32BE(12);
 
-    // Get command byte
-    const commandByte = buffer.readUInt8(11);
-
     // Check for payload
     if (buffer.length - 8 < payloadSize) {
       throw new TypeError(`Packet missing payload: payload has length ${payloadSize}.`);
@@ -174,20 +173,23 @@ class MessageParser {
       return false;
     }
 
-    // Try to parse data as JSON.
-    // If error, return as string.
+    // Try to decrypt data first.
     try {
-      data = JSON.parse(data);
-    } catch (error) { // Data is encrypted
-      data = data.toString('ascii');
+      if (!this.cipher) {
+        throw new Error('Missing key or version in constructor.');
+      }
 
-      try {
-        if (!this.cipher) {
-          throw new Error('Missing key or version in constructor.');
-        }
+      data = this.cipher.decrypt(data);
+    } catch (error) {
+      data = data.toString('utf8');
+    }
 
-        data = this.cipher.decrypt(data);
-      } catch (donothing) {}
+    // Try to parse data as JSON.
+    // If error, return as string.
+    if (typeof data === 'string') {
+      try {
+        data = JSON.parse(data);
+      } catch (error) { }
     }
 
     return data;
@@ -242,13 +244,43 @@ class MessageParser {
    * @returns {Buffer}
    */
   encode(options) {
-    // Ensure data is a Buffer
-    let payload;
+    // Check command byte
+    if (Object.values(CommandType).indexOf(options.commandByte) === -1) {
+      throw new TypeError('Command byte not defined.');
+    }
 
-    // Encrypt data if necessary
-    if (options.encrypted) {
+    // Convert Objects to Strings, Strings to Buffers
+    if (!(options.data instanceof Buffer)) {
+      if (typeof options.data !== 'string') {
+        options.data = JSON.stringify(options.data);
+      }
+
+      options.data = Buffer.from(options.data);
+    }
+
+    // Construct payload
+    let payload = options.data;
+
+    // Protocol 3.3 is always encrypted
+    if (this.version === '3.3') {
+      // Encrypt data
+      payload = this.cipher.encrypt({
+        data: payload,
+        base64: false
+      });
+
+      // Check if we need an extended header, only for certain CommandTypes
+      if (options.commandByte !== CommandType.DP_QUERY) {
+        // Add 3.3 header
+        const buffer = Buffer.alloc(payload.length + 15);
+        Buffer.from('3.3').copy(buffer, 0);
+        payload.copy(buffer, 15);
+        payload = buffer;
+      }
+    } else if (options.encrypted) {
+      // Protocol 3.1 and below, only encrypt data if necessary
       payload = this.cipher.encrypt({
-        data: JSON.stringify(options.data)
+        data: payload
       });
 
       // Create MD5 signature
@@ -258,19 +290,6 @@ class MessageParser {
 
       // Create byte buffer from hex data
       payload = Buffer.from(this.version + md5 + payload);
-    } else if (options.data instanceof Buffer) {
-      payload = options.data;
-    } else {
-      if (typeof options.data !== 'string') {
-        options.data = JSON.stringify(options.data);
-      }
-
-      payload = Buffer.from(options.data);
-    }
-
-    // Check command byte
-    if (Object.values(CommandType).indexOf(options.commandByte) === -1) {
-      throw new TypeError('Command byte not defined.');
     }
 
     // Allocate buffer with room for payload + 24 bytes for