关于 SM4 加秘密解密的工具类（转载）

怼烎@ 2022-12-10 08:55 127阅读 0赞

1、需要依赖：

<dependency>
                <groupId>org.bouncycastle</groupId>
                <artifactId>bcprov-jdk15on</artifactId>
                <version>1.66</version>
            </dependency>
    
            <dependency>
                <groupId>cn.hutool</groupId>
                <artifactId>hutool-all</artifactId>
                <version>5.4.1</version>
            </dependency>

2、工具类

package com.wlhy.utils;
    
    import org.bouncycastle.jce.provider.BouncyCastleProvider;
    import org.bouncycastle.pqc.math.linearalgebra.ByteUtils;
    
    import javax.crypto.Cipher;
    import javax.crypto.spec.SecretKeySpec;
    import java.security.Key;
    import java.security.Security;
    import java.util.Arrays;
    
    public class Sm4Util {
    
    	  static {
    	        Security.addProvider(new BouncyCastleProvider());
    	    }
    	    private static final String ENCODING = "UTF-8";
    	    public static final String ALGORITHM_NAME = "SM4";
    	    // PKCS5Padding  NoPadding 补位规则，PKCS5Padding缺位补0，NoPadding不补
    	    public static final String ALGORITHM_NAME_ECB_PADDING = "SM4/ECB/PKCS5Padding";
    	 
    	    /**
    	     * ECB加密模式，无向量
    	     * @explain ECB
    	     * @param algorithmName
    	     * @param mode
    	     * @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;
    	    }
    	    /**
    	     * 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[]
    	        //当加密数据为16进制字符串时使用这行
    //	        byte[] srcData = ByteUtils.fromHexString(hexKey);
    	        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
    	     * @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);//声称Ecb暗号,通过第二个参数判断加密还是解密
    	        return cipher.doFinal(data);
    	    }
    	 
    	    //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);//生成Ecb暗号,通过第二个参数判断加密还是解密
    	        return cipher.doFinal(cipherText);
    	    }
    	    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;
    	    }
    
    	    public static void main(String[] args) {
    	        try {
    	            System.out.println("开始****************************");
    	            String json = "xxxxxx";
    	            System.out.println("加密前："+json);
    	            //自定义的32位16进制秘钥
    	            String key = "76747161590C11EA8FBA40167E2083BB ";
    	            String cipher = encryptEcb(key,json);//sm4加密
    	            System.out.println("加密后："+cipher);
    	            System.out.println("校验："+verifyEcb(key,cipher,json));//校验加密前后是否为同一数据
    
    				cipher = "jiami";
    	            json =decryptEcb(key,cipher);//解密
    	            System.out.println("解密后："+json);
    	            System.out.println("结束****************************");
    	        } catch (Exception e) {
    	            e.printStackTrace();
    	        }
    	 
    	    }
    
    }