Android SM2加密解密

Android中使用SM2算法进行加密解密的步骤如下：

1. 导入相关库和类：

import org.bouncycastle.crypto.AsymmetricCipherKeyPair;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.InvalidCipherTextException;
import org.bouncycastle.crypto.engines.SM2Engine;import org.bouncycastle.crypto.generators.ECKeyPairGenerator;
import org.bouncycastle.crypto.params.ECKeyGenerationParameters;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.params.ParametersWithRandom;
import org.bouncycastle.crypto.util.PrivateKeyFactory;
import org.bouncycastle.crypto.util.PublicKeyFactory;
import org.bouncycastle.jce.provider.BouncyCastleProvider;import org.bouncycastle.util.encoders.Base64;
import java.security.Security;

2. 初始化BouncyCastleProvider：

Security.addProvider(new BouncyCastleProvider());

3. 生成密钥对：

ECKeyPairGenerator generator = new ECKeyPairGenerator();
ECKeyGenerationParameters keyGenParams = new ECKeyGenerationParameters(SM2NamedCurves.getByName("sm2p256v1"), new SecureRandom());
generator.init(keyGenParams);
AsymmetricCipherKeyPair keyPair = generator.generateKeyPair();
ECPrivateKeyParameters privateKey = (ECPrivateKeyParameters) keyPair.getPrivate();
ECPublicKeyParameters publicKey = (ECPublicKeyParameters) keyPair.getPublic();

4. 将公钥和私钥转换为字符串形式：

String privateKeyStr = Base64.toBase64String(privateKey.getD().toByteArray());
String publicKeyStr = Base64.toBase64String(publicKey.getQ().getEncoded(false));

5. 加密数据：

String plainText = "Hello, World!";
byte[] plainBytes = plainText.getBytes("UTF-8");
CipherParameters encryptParams = new ParametersWithRandom(publicKey, new SecureRandom());
SM2Engine engine = new SM2Engine();
engine.init(true, encryptParams);
byte[] cipherBytes = engine.processBlock(plainBytes, 0, plainBytes.length);
String cipherText = Base64.toBase64String(cipherBytes);

6. 解密数据：

byte[] cipherBytes = Base64.decode(cipherText);
CipherParameters decryptParams = new ParametersWithRandom(privateKey, new SecureRandom());
engine.init(false, decryptParams);
byte[] decryptedBytes = engine.processBlock(cipherBytes, 0, cipherBytes.length);
String decryptedText = new String(decryptedBytes, "UTF-8");

注意：以上代码仅为示例，实际使用时需要根据具体情况进行适当的修改和处理。