Flutter加密通信插件x25519的使用

发布于 1周前 作者 h691938207 来自 Flutter

Flutter加密通信插件x25519的使用

标题

Flutter加密通信插件x25519的使用

内容

Dart port of Curve25519

Pub package

Usage

import 'package:x25519/x255119.dart';

void genKeyAndX25519() {
  var aliceKeyPair = generateKeyPair();
  var bobKeyPair = generateKeyPair();

  var aliceSharedKey = X25519(aliceKeyPair.privateKey, bobKeyPair.publicKey);
  var bobSharedKey = X25519(bobKeyPair.privateKey, aliceKeyPair.publicKey);

  assert(ListEquality().equals(aliceSharedKey, bobSharedKey));
}

void useX25519() {
  const expectedHex =
      '89161fde887b2b53de549af483940106ecc114d6982daa98256de23bdf77661a';
  var x = List<int>.filled(32, 0);
  x[0] = 1;

  for (var i = 0; i &lt; 200; i++) {
    x = X25519(x, basePoint);
  }
  assert(HEX.encode(x) == expectedHex);
}

示例代码

import 'package:collection/collection.dart';
import 'package:hex/hex.dart';
import 'package:x25519/x25519.dart';

void genKeyAndX25519() {
  var aliceKeyPair = generateKeyPair();
  var bobKeyPair = generateKeyPair();

  var aliceSharedKey = X25519(aliceKeyPair.privateKey, bobKeyPair.publicKey);
  var bobSharedKey = X25519(bobKeyPair.privateKey, aliceKeyPair.publicKey);

  assert(ListEquality().equals(aliceSharedKey, bobSharedKey));
}

void useX25519() {
  const expectedHex =
      '89161fde887b2b53de549af483940106ecce114d6982daa98256de23bdf77661a';
  var x = List&lt;int&gt;.filled(32, 0);
  x[0] = 1;

  for (var i = 0; i &lt; 200; i++) {
    x = X25519(x, basePoint);
  }
  assert(HEX.encode(x) == expectedHex);
}

更多关于Flutter加密通信插件x25519的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html

1 回复

更多关于Flutter加密通信插件x25519的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html


在Flutter中实现基于x25519的加密通信,你可以使用pointycastle这个Dart库,它提供了多种加密算法的实现,包括x25519。虽然Flutter本身没有直接提供x25519的插件,但你可以通过pointycastle来实现。

以下是一个简单的示例,展示了如何在Flutter中使用pointycastle库进行x25519密钥交换和加密通信:

  1. 添加依赖: 首先,你需要在pubspec.yaml文件中添加pointycastle依赖:

    dependencies:
      flutter:
        sdk: flutter
      pointycastle: ^3.0.1  # 确保版本号是最新的
    
  2. 导入库: 在你的Dart文件中导入pointycastle库:

    import 'package:pointycastle/export.dart';
    import 'dart:typed_data';
    
  3. 生成密钥对: 使用X25519KeyPairGenerator生成x25519密钥对:

    SecureRandom secureRandom = FortunaRandom();
    X25519KeyPairGenerator keyPairGenerator = X25519KeyPairGenerator();
    keyPairGenerator.init(ParametersWithRandom(null, secureRandom));
    
    AsymmetricKeyPair<PublicKey, PrivateKey> keyPair = keyPairGenerator.generateKeyPair();
    Uint8List privateKey = keyPair.private.encoded;
    Uint8List publicKey = keyPair.public.encoded;
    
  4. 密钥交换: 假设你有对方的公钥,你可以使用自己的私钥和对方的公钥进行密钥交换:

    Uint8List theirPublicKey = ...; // 从对方获取的公钥
    
    X25519PrivateKeyParameters privateKeyParams = X25519PrivateKeyParameters(privateKey);
    X25519PublicKeyParameters publicKeyParams = X25519PublicKeyParameters(theirPublicKey);
    
    X25519KeyAgreement keyAgreement = X25519KeyAgreement();
    keyAgreement.init(privateKeyParams);
    
    BigInteger sharedSecret = keyAgreement.processKey(publicKeyParams);
    Uint8List sharedSecretBytes = sharedSecret.toByteArrayUnsigned();
    
  5. 加密和解密: 使用共享密钥进行对称加密和解密。这里可以使用AES等对称加密算法:

    import 'package:pointycastle/api.dart';
    import 'package:pointycastle/block/aes.dart';
    import 'package:pointycastle/paddings/pkcs7.dart';
    import 'package:pointycastle/modes/cbc.dart';
    
    SecureRandom aesRandom = FortunaRandom();
    KeyParameter aesKey = KeyParameter(sharedSecretBytes.sublist(0, 32)); // AES-256
    
    PaddedBufferedBlockCipher cipher = PaddedBufferedBlockCipher(CBCBlockCipher(AESFastEngine()));
    ParametersWithIV<KeyParameter> aesParams = ParametersWithIV<KeyParameter>(aesKey, Uint8List(16).fillRange(0, 16, (i) => aesRandom.nextInt(256)));
    
    cipher.init(true, aesParams); // 初始化为加密模式
    Uint8List input = Uint8List.fromList('Hello, Flutter!'.codeUnits);
    Uint8List encrypted = cipher.processBytes(input, 0, input.length);
    Uint8List encryptedFinal = cipher.doFinal();
    Uint8List encryptedData = Uint8List.concat([encrypted, encryptedFinal]);
    
    cipher.init(false, aesParams); // 初始化为解密模式
    Uint8List decrypted = cipher.processBytes(encryptedData, 0, encryptedData.length);
    Uint8List decryptedFinal = cipher.doFinal();
    Uint8List decryptedData = Uint8List.concat([decrypted, decryptedFinal]);
    
    String decryptedText = String.fromCharCodes(decryptedData);
    print('Decrypted Text: $decryptedText'); // 应该输出: Hello, Flutter!
    

这个示例展示了如何在Flutter中使用pointycastle库进行x25519密钥交换,并使用生成的共享密钥进行AES加密和解密。请注意,这只是一个简单的示例,实际使用中你可能需要处理更多的边缘情况和安全性问题。

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