java实现SM4加解密
时间: 2023-07-26 13:17:28 浏览: 80
好的,以下是Java实现SM4加解密的示例代码。需要注意的是,该代码需要依赖Bouncy Castle库,可以通过Maven等方式进行引入。
```java
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.engines.SM4Engine;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.crypto.params.ParametersWithIV;
import org.bouncycastle.crypto.params.SM4Parameters;
import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
import org.bouncycastle.crypto.params.IvParameterSpec;
import org.bouncycastle.util.encoders.Hex;
import java.nio.charset.StandardCharsets;
import java.security.Security;
public class SM4Util {
static {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
}
/**
* SM4加密
* @param key 密钥
* @param iv 向量
* @param data 待加密数据
* @return 加密后的数据
*/
public static byte[] encrypt(byte[] key, byte[] iv, byte[] data) {
SM4Engine engine = new SM4Engine();
PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(engine);
// 加密模式
CipherParameters params = new ParametersWithIV(new KeyParameter(key), new IvParameterSpec(iv));
cipher.init(true, params);
byte[] out = new byte[cipher.getOutputSize(data.length)];
int len = cipher.processBytes(data, 0, data.length, out, 0);
try {
len += cipher.doFinal(out, len);
} catch (Exception e) {
e.printStackTrace();
}
byte[] result = new byte[len];
System.arraycopy(out, 0, result, 0, len);
return result;
}
/**
* SM4解密
* @param key 密钥
* @param iv 向量
* @param data 待解密数据
* @return 解密后的数据
*/
public static byte[] decrypt(byte[] key, byte[] iv, byte[] data) {
SM4Engine engine = new SM4Engine();
PaddedBufferedBlockCipher cipher = new PaddedBufferedBlockCipher(engine);
// 解密模式
CipherParameters params = new ParametersWithIV(new KeyParameter(key), new IvParameterSpec(iv));
cipher.init(false, params);
byte[] out = new byte[cipher.getOutputSize(data.length)];
int len = cipher.processBytes(data, 0, data.length, out, 0);
try {
len += cipher.doFinal(out, len);
} catch (Exception e) {
e.printStackTrace();
}
byte[] result = new byte[len];
System.arraycopy(out, 0, result, 0, len);
return result;
}
public static void main(String[] args) {
byte[] key = Hex.decode("0123456789abcdeffedcba9876543210");
byte[] iv = Hex.decode("0123456789abcdeffedcba9876543210");
byte[] data = "Hello, world!".getBytes(StandardCharsets.UTF_8);
byte[] encrypted = encrypt(key, iv, data);
System.out.println("Encrypted: " + Hex.toHexString(encrypted));
byte[] decrypted = decrypt(key, iv, encrypted);
System.out.println("Decrypted: " + new String(decrypted, StandardCharsets.UTF_8));
}
}
```
其中,`encrypt`和`decrypt`方法分别代表SM4加密和解密的实现,需要传入密钥`key`、向量`iv`和待加密/解密的数据`data`,返回加密/解密后的数据。在示例代码中,我们使用了Bouncy Castle库提供的`SM4Engine`和`PaddedBufferedBlockCipher`来实现SM4的加解密,使用`ParametersWithIV`来指定加密/解密模式和参数。
在`main`方法中,我们对一个字符串进行SM4加解密,并打印出加解密后的结果,供参考。