refactor getTag

inwaar · Oct 6, 2024 · d4acf8f · d4acf8f
1 parent 271b0c2
commit d4acf8f
Show file tree

Hide file tree

Showing 2 changed files with 42 additions and 51 deletions.
diff --git a/src/client.js b/src/client.js
@@ -140,18 +140,18 @@ class Client extends EventEmitter {
         this._transformer = new PropertyTransformer();
 
         /**
-         * Client options
-         *
-         * @type {CLIENT_OPTIONS}
+         * @type {EncryptionService}
          * @private
          */
-        this._options = { ...CLIENT_OPTIONS, ...options };
+        this._encryptionService;
 
         /**
-         * @type {EncryptionService}
+         * Client options
+         *
+         * @type {CLIENT_OPTIONS}
          * @private
          */
-        this._encryptionService = new EncryptionService();
+        this._options = { ...CLIENT_OPTIONS, ...options };
 
         /**
          * @private
@@ -212,6 +212,9 @@ class Client extends EventEmitter {
     async _initialize() {
         this._dispose();
 
+        // The encryption service is stateful so requires re-initialization
+        this._encryptionService = new EncryptionService();
+
         try {
             await this._socketSend({ t: 'scan' });
             await this._reconnect();
@@ -360,17 +363,19 @@ class Client extends EventEmitter {
      * @private
      */
     async _sendBindRequest() {
+        const encryptedMessage = this._encryptionService.encrypt({
+            mac: this._cid,
+            t: 'bind',
+            uid: 0,
+        });
+
         await this._socketSend({
             cid: 'app',
             i: 1,
             t: 'pack',
             uid: 0,
-            pack: this._encryptionService.encrypt({
-                mac: this._cid,
-                t: 'bind',
-                uid: 0,
-            }),
-            tag: this._encryptionService.getTag(),
+            pack: encryptedMessage.payload,
+            tag: encryptedMessage.tag,
         });
     }
 
@@ -417,13 +422,15 @@ class Client extends EventEmitter {
      */
     async _sendRequest(message) {
         this._trace('OUT.MSG', message, this._encryptionService.getKey());
+
+        const encryptedMessage = this._encryptionService.encrypt(message);
         await this._socketSend({
             cid: 'app',
             i: 0,
             t: 'pack',
             uid: 0,
-            pack: this._encryptionService.encrypt(message),
-            tag: this._encryptionService.getTag(),
+            pack: encryptedMessage.payload,
+            tag: encryptedMessage.tag,
         });
     }
 

diff --git a/src/encryption-service.js b/src/encryption-service.js
@@ -2,6 +2,13 @@
 
 const crypto = require('crypto');
 
+/**
+ * @typedef EncryptedMessage
+ * @property {string} payload
+ * @property {string|undefined} tag
+ * @private
+ */
+
 /**
  * @private
  */
@@ -63,20 +70,10 @@ class EncryptionService {
      * Encrypt UDP message
      *
      * @param {object} output Request object
-     * @returns {string}
+     * @returns {EncryptedMessage}
      */
     encrypt(output) {
-        const result = this._activeCipher.encrypt(output);
-        return result;
-    }
-
-    /**
-     * Required for GCM
-     *
-     * @returns {string|undefined}
-     */
-    getTag() {
-        return this._activeCipher.getTag();
+        return this._activeCipher.encrypt(output);
     }
 }
 
@@ -128,21 +125,15 @@ class EcbCipher {
      * Encrypt UDP message
      *
      * @param {object} output Request object
-     * @returns {string}
+     * @returns {EncryptedMessage}
      */
     encrypt(output) {
         const cipher = crypto.createCipheriv('aes-128-ecb', this._key, '');
         const str = cipher.update(JSON.stringify(output), 'utf8', 'base64');
-        return str + cipher.final('base64');
-    }
-
-    /**
-     * Not applicable for ECB
-     *
-     * @returns {string|undefined}
-     */
-    getTag() {
-        return undefined;
+        const encrypted = str + cipher.final('base64');
+        return {
+            payload: encrypted,
+        };
     }
 }
 
@@ -209,10 +200,10 @@ class GcmCipher {
     }
 
     /**
-     * Encrypt UDP message. Sets _encTag to be received before sending with getTag() and added to message.
+     * Encrypt UDP message
      *
      * @param {object} output Request object
-     * @returns {string}
+     * @returns {EncryptedMessage}
      */
     encrypt(output) {
         const cipher = crypto.createCipheriv(
@@ -223,19 +214,12 @@ class GcmCipher {
         cipher.setAAD(GCM_AEAD);
         const str = cipher.update(JSON.stringify(output), 'utf8', 'base64');
         const outstr = str + cipher.final('base64');
-        this._encTag = cipher.getAuthTag().toString('base64').toString('utf-8');
-        return outstr;
-    }
+        const tag = cipher.getAuthTag().toString('base64').toString('utf-8');
 
-    /**
-     * Receive and clear the last generated tag
-     *
-     * @returns {string|undefined}
-     */
-    getTag() {
-        const tmpTag = this._encTag;
-        this._encTag = undefined;
-        return tmpTag;
+        return {
+            payload: outstr,
+            tag,
+        };
     }
 }