JAVA实现 SM4 ECB加密（不使用ECBBlockCiphe）

jar下载链接：

Download Bouncy Castle Java - BouncycastleDownload our Bouncy Castle Java APIs through GitHub, Maven, or our website for a comprehensive and flexible set of cryptographic functions.https://www.bouncycastle.org/download/bouncy-castle-java/

代码：

import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.engines.SM4Engine;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.util.encoders.Hex;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class Sm4Util {

    public static byte[] hexStringToByteArray(String hexString) {
        return Hex.decode(hexString);
    }

    public static String encryptToString(String plainText, String hexKey) {
        // 将十六进制密钥转换为字节数组
        byte[] keyBytes = hexStringToByteArray(hexKey);
        SM4Engine engine = new SM4Engine();
        CipherParameters param = new KeyParameter(keyBytes);
        engine.init(true, param);

        byte[] data = plainText.getBytes(StandardCharsets.UTF_8);
        int blockSize = engine.getBlockSize();
        int outputLength = data.length + (data.length % blockSize == 0? 0 : blockSize - (data.length % blockSize));
        byte[] output = new byte[outputLength];

        for (int i = 0; i < data.length; i += blockSize) {
            byte[] block = new byte[blockSize];
            System.arraycopy(data, i, block, 0, Math.min(data.length - i, blockSize));
            byte[] encryptedBlock = new byte[blockSize];
            engine.processBlock(block, 0, encryptedBlock, 0);
            System.arraycopy(encryptedBlock, 0, output, i, Math.min(encryptedBlock.length, output.length - i));
        }

        // 使用 Base64 编码加密结果
        return Base64.getEncoder().encodeToString(output);
    }

    public static void main(String[] args) {
        String plainText = "Admin@2024";      //待加密内容
        String hexKey = "6417849756d1f61073901258fcc7a686";    //32位16进制密钥

        String encryptedText = encryptToString(plainText, hexKey);
        System.out.println("加密后的文本：" + encryptedText);
    }
}