使用加密包的填充块无效或损坏

Question

我有一段时间使用加密包来解密来自服务器的消息，这些消息是我在一切工作正常之前加密的，但是当我从 pubspec.yaml 文件中清理我的包时，会出现此错误：

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无效参数：无效或损坏的填充块

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这很令人困惑，我认为问题根本不是来自于清洁包装。

我的代码：

import 'package:encrypt/encrypt.dart' as encrypt;

class EncryptMessages{

  static encryptWithAESKey(String data) {
    encrypt.Key aesKey = encrypt.Key.fromLength(16);
    final encrypter = encrypt.Encrypter(encrypt.AES(aesKey));
    encrypt.Encrypted encryptedData =
    encrypter.encrypt(data, iv: encrypt.IV.fromLength(16)); ///allZerosOfLength
    return encryptedData.base64;
  }

  static decryptWithAESKey(String data) {
    encrypt.Key aesKey = encrypt.Key.fromLength(16);
    final encrypter = encrypt.Encrypter(encrypt.AES(aesKey));
    encrypt.Encrypted encrypted = encrypt.Encrypted.fromBase64(data);
    String decryptedData =
    encrypter.decrypt(encrypted, iv: encrypt.IV.fromLength(16)); ///allZerosOfLength
    return decryptedData;
  }
}

使用加密：^5.0.3

我尝试将软件包版本更改为^5.0.1，^5.0.2

我尝试了allZerosOfLength

我尝试填充到“PKCS7”

Answer 1

我也面临同样的错误

原因：IV值不是恒定的，每次运行时都会产生新的值。 要解密数据，我们需要使用与加密数据相同的 IV。

解决方案：

1. 生成IV
2. 像密钥一样存储 IV 的 base64 以安全存储

代码

import 'package:encrypt/encrypt.dart' as encrypt;
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

class SecureStorage {
  SecureStorage._();

  static final SecureStorage _instance = SecureStorage._();

  factory SecureStorage() {
    return _instance;
  }

  final _storage = const FlutterSecureStorage();

  late encrypt.Key encryptionKey;
  late encrypt.IV iv;

  Future<void> init() async {
    await _getKey();
    await _getIV();
  }

  Future<void> _getKey() async {
    String? key = await _storage.read(key: 'encryptionKey');
    if (key == null) {
      key = encrypt.Key.fromLength(32).base64; // Create a new key if not exists
      await _storage.write(key: 'encryptionKey', value: key);
    }
    encryptionKey = encrypt.Key.fromBase64(key);
  }

  Future<void> _getIV() async {
    String? iv64 = await _storage.read(key: 'encryptionIV');
    if (iv64 == null) {
      iv64 = encrypt.IV.fromLength(16).base64; // Create a new IV if not exists
      await _storage.write(key: 'encryptionIV', value: iv64);
    }
    iv = encrypt.IV.fromBase64(iv64);
  }

  String encryptData(String data) {
    final encrypter = encrypt.Encrypter(encrypt.AES(encryptionKey));
    final encrypted = encrypter.encrypt(data, iv: iv);
    return encrypted.base64;
  }

  String decryptData(String encryptedData) {
    final encrypter = encrypt.Encrypter(encrypt.AES(encryptionKey));
    return encrypter.decrypt64(encryptedData, iv: iv);
  }
}