fix(NetworkConfigManager, server): enhance IPSec password encryption and decryption error handling; add validation for encrypted password format and improve logging for better debugging

backend/utils/encryption.js

@@ -53,30 +53,61 @@ function encrypt(text) {
  * @returns {string} - Расшифрованный текст
  */
 function decrypt(encryptedText) {
-  if (!encryptedText) return '';
+  if (!encryptedText) {
+    throw new Error('Encrypted text is empty');
+  }
+  
+  if (typeof encryptedText !== 'string') {
+    throw new Error('Encrypted text must be a string');
+  }
   
   try {
     const parts = encryptedText.split(':');
     if (parts.length !== 3) {
-      throw new Error('Invalid encrypted format');
+      throw new Error(`Invalid encrypted format: expected 3 parts separated by ':', got ${parts.length}`);
     }
     
     const [ivBase64, authTagBase64, encryptedBase64] = parts;
-    const iv = Buffer.from(ivBase64, 'base64');
-    const authTag = Buffer.from(authTagBase64, 'base64');
-    const encrypted = encryptedBase64;
+    
+    if (!ivBase64 || !authTagBase64 || !encryptedBase64) {
+      throw new Error('Invalid encrypted format: one or more parts are empty');
+    }
+    
+    let iv, authTag;
+    try {
+      iv = Buffer.from(ivBase64, 'base64');
+      authTag = Buffer.from(authTagBase64, 'base64');
+    } catch (bufferError) {
+      throw new Error(`Failed to decode base64: ${bufferError.message}`);
+    }
+    
+    if (iv.length !== 16) {
+      throw new Error(`Invalid IV length: expected 16 bytes, got ${iv.length}`);
+    }
+    
+    if (authTag.length !== 16) {
+      throw new Error(`Invalid auth tag length: expected 16 bytes, got ${authTag.length}`);
+    }
     
     const key = getEncryptionKey();
     const decipher = crypto.createDecipheriv(ALGORITHM, key, iv);
     decipher.setAuthTag(authTag);
     
-    let decrypted = decipher.update(encrypted, 'base64', 'utf8');
+    let decrypted = decipher.update(encryptedBase64, 'base64', 'utf8');
     decrypted += decipher.final('utf8');
     
     return decrypted;
   } catch (error) {
-    console.error('Decryption error:', error);
-    throw new Error('Failed to decrypt data');
+    if (error.message.includes('Unsupported state') || error.message.includes('bad decrypt')) {
+      throw new Error(`Decryption failed: possibly wrong encryption key or corrupted data. Original error: ${error.message}`);
+    }
+    console.error('Decryption error details:', {
+      error: error.message,
+      stack: error.stack,
+      encryptedTextLength: encryptedText.length,
+      encryptedTextPreview: encryptedText.substring(0, 100)
+    });
+    throw error;
   }
 }