java sm4国密算法加密、解密

1.准备工作

  所需jar包:

  bcprov-jdk15on-1.59.jar

  commons-lang3-3.1.jar

  20200901

  对应的maven依赖

<!--sm3,sm4加密算法-->
<dependency>
    <groupId>org.bouncycastle</groupId>
    <artifactId>bcprov-jdk15on</artifactId>
    <version>1.66</version>
</dependency>  
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.SecureRandom;
import java.security.Security;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.pqc.math.linearalgebra.ByteUtils;
/**
 * sm4加密算法工具类
 * @explain sm4加密、解密与加密结果验证
 *          可逆算法
 * @author Marydon
 * @creationTime 2018年7月6日上午11:46:59
 * @version 1.0
 * @since
 * @email marydon20170307@163.com
 */
public class Sm4Util {

    static {
        Security.addProvider(new BouncyCastleProvider());
    }

    private static final String ENCODING = "UTF-8";
    public static final String ALGORITHM_NAME = "SM4";
    // 加密算法/分组加密模式/分组填充方式
    // PKCS5Padding-以8个字节为一组进行分组加密
    // 定义分组加密模式使用:PKCS5Padding
    public static final String ALGORITHM_NAME_ECB_PADDING = "SM4/ECB/PKCS5Padding";
    // 128-32位16进制;256-64位16进制
    public static final int DEFAULT_KEY_SIZE = 128;
    
    /**
     * 生成ECB暗号
     * @explain ECB模式(电子密码本模式:Electronic codebook)
     * @param algorithmName
     *            算法名称
     * @param mode
     *            模式
     * @param key
     * @return
     * @throws Exception
     */
    private static Cipher generateEcbCipher(String algorithmName, int mode, byte[] key) throws Exception {
        Cipher cipher = Cipher.getInstance(algorithmName, BouncyCastleProvider.PROVIDER_NAME);
        Key sm4Key = new SecretKeySpec(key, ALGORITHM_NAME);
        cipher.init(mode, sm4Key);
        return cipher;
    }
}

2.SM4加密

  第一步:产生密钥

  方式一:系统生成密钥

/**
 * 自动生成密钥
 * @explain
 * @return
 * @throws NoSuchAlgorithmException
 * @throws NoSuchProviderException
 */
public static byte[] generateKey() throws Exception {
    return generateKey(DEFAULT_KEY_SIZE);
}

/**
 * @explain
 * @param keySize
 * @return
 * @throws Exception
 */
public static byte[] generateKey(int keySize) throws Exception {
    KeyGenerator kg = KeyGenerator.getInstance(ALGORITHM_NAME, BouncyCastleProvider.PROVIDER_NAME);
    kg.init(keySize, new SecureRandom());
    return kg.generateKey().getEncoded();
}  

  方法二:自己提供16进制的密钥

  第二步:加密

/**
 * sm4加密
 * @explain 加密模式:ECB
 *          密文长度不固定,会随着被加密字符串长度的变化而变化
 * @param hexKey
 *            16进制密钥(忽略大小写)
 * @param paramStr
 *            待加密字符串
 * @return 返回16进制的加密字符串
 * @throws Exception
 */
public static String encryptEcb(String hexKey, String paramStr) throws Exception {
    String cipherText = "";
    // 16进制字符串-->byte[]
    byte[] keyData = ByteUtils.fromHexString(hexKey);
    // String-->byte[]
    byte[] srcData = paramStr.getBytes(ENCODING);
    // 加密后的数组
    byte[] cipherArray = encrypt_Ecb_Padding(keyData, srcData);
    // byte[]-->hexString
    cipherText = ByteUtils.toHexString(cipherArray);
    return cipherText;
}

/**
 * 加密模式之Ecb
 * @explain
 * @param key
 * @param data
 * @return
 * @throws Exception
 */
public static byte[] encrypt_Ecb_Padding(byte[] key, byte[] data) throws Exception {
    Cipher cipher = generateEcbCipher(ALGORITHM_NAME_ECB_PADDING, Cipher.ENCRYPT_MODE, key);
    return cipher.doFinal(data);
}

3.SM4解密

/**
 * sm4解密
 * @explain 解密模式:采用ECB
 * @param hexKey
 *            16进制密钥
 * @param cipherText
 *            16进制的加密字符串(忽略大小写)
 * @return 解密后的字符串
 * @throws Exception
 */
public static String decryptEcb(String hexKey, String cipherText) throws Exception {
    // 用于接收解密后的字符串
    String decryptStr = "";
    // hexString-->byte[]
    byte[] keyData = ByteUtils.fromHexString(hexKey);
    // hexString-->byte[]
    byte[] cipherData = ByteUtils.fromHexString(cipherText);
    // 解密
    byte[] srcData = decrypt_Ecb_Padding(keyData, cipherData);
    // byte[]-->String
    decryptStr = new String(srcData, ENCODING);
    return decryptStr;
}
    
/**
 * 解密
 * @explain
 * @param key
 * @param cipherText
 * @return
 * @throws Exception
 */
public static byte[] decrypt_Ecb_Padding(byte[] key, byte[] cipherText) throws Exception {
    Cipher cipher = generateEcbCipher(ALGORITHM_NAME_ECB_PADDING, Cipher.DECRYPT_MODE, key);
    return cipher.doFinal(cipherText);
}  

4.加密数据校验

/**
 * 校验加密前后的字符串是否为同一数据
 * @explain
 * @param hexKey
 *            16进制密钥(忽略大小写)
 * @param cipherText
 *            16进制加密后的字符串
 * @param paramStr
 *            加密前的字符串
 * @return 是否为同一数据
 * @throws Exception
 */
public static boolean verifyEcb(String hexKey, String cipherText, String paramStr) throws Exception {
    // 用于接收校验结果
    boolean flag = false;
    // hexString-->byte[]
    byte[] keyData = ByteUtils.fromHexString(hexKey);
    // 将16进制字符串转换成数组
    byte[] cipherData = ByteUtils.fromHexString(cipherText);
    // 解密
    byte[] decryptData = decrypt_Ecb_Padding(keyData, cipherData);
    // 将原字符串转换成byte[]
    byte[] srcData = paramStr.getBytes(ENCODING);
    // 判断2个数组是否一致
    flag = Arrays.equals(decryptData, srcData);
    return flag;
}  

5.测试

public static void main(String[] args) {
    try {
        String json = "{\"name\":\"Marydon\",\"website\":\"http://www.cnblogs.com/Marydon20170307\"}";
        // 自定义的32位16进制密钥
        String key = "86C63180C2806ED1F47B859DE501215B";
        String cipher = Sm4Utils.encryptEcb(key, json);
        System.out.println(cipher);//05a087dc798bb0b3e80553e6a2e73c4ccc7651035ea056e43bea9d125806bf41c45b4263109c8770c48c5da3c6f32df444f88698c5c9fdb5b0055b8d042e3ac9d4e3f7cc67525139b64952a3508a7619
        System.out.println(Sm4Utils.verifyEcb(key, cipher, json));// true
        json = Sm4Utils.decryptEcb(key, cipher);
        System.out.println(json);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

 

posted @ 2018-07-06 11:44  Marydon  阅读(78743)  评论(10编辑  收藏  举报