需求
第三方交互，要求国密SM4进行加密，故引入。
SM4为对称加密，用就完事。
引入Maven依赖
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcprov-jdk15on</artifactId>
<version>1.57</version>
</dependency>
SM4Utils工具类
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.pqc.math.linearalgebra.ByteUtils;
import xyz.diuut.pojo.BaseSmEnum;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.AlgorithmParameters;
import java.security.Key;
import java.security.SecureRandom;
import java.security.Security;
import java.util.Arrays;
/**
* @description:
* @author: Diuut
* @date: 2022/5/31 10:56
*/
public class SM4Utils {
static {
Security.addProvider(new BouncyCastleProvider());
}
private static final String ENCODING = BaseSmEnum.ENCODING.getMsg();
public static final String ALGORITHM_NAME = BaseSmEnum.ALGORITHM_NAME.getMsg();
// 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_CBC_PADDING = BaseSmEnum.ALGORITHM_NAME_CBC_PADDING.getMsg();
public static final String ALGORITHM_NAME_ECB_PADDING = BaseSmEnum.ALGORITHM_NAME_ECB_PADDING.getMsg();
// 128-32位16进制；256-64位16进制
public static final int DEFAULT_KEY_SIZE = 128;
/**
* 自动生成密钥
*
* @return
* @explain
*/
public static byte[] generateKey() throws Exception {
return generateKey(DEFAULT_KEY_SIZE);
}
public static String generateKeyString() throws Exception {
return ByteUtils.toHexString(generateKey());
}
/**
* @param keySize
* @return
* @throws Exception
* @explain
*/
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();
}
/**
* sm4加密_CBC
*
* @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
* @explain 加密模式：CBC
*/
public static String protectMsg_CBC(String hexKey, String paramStr) throws Exception {
String result = "";
// 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_Cbc_Padding(keyData, srcData);
// byte[]-->hexString
result = ByteUtils.toHexString(cipherArray);
return result;
}
/**
* sm4加密_ECB
*
* @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
* @explain 加密模式：CBC
*/
public static String protectMsg_ECB(String hexKey, String paramStr) throws Exception {
String result = "";
// 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
result = ByteUtils.toHexString(cipherArray);
return result;
}
/**
* 加密模式之CBC
*
* @param key
* @param data
* @return
* @throws Exception
* @explain
*/
public static byte[] encrypt_Cbc_Padding(byte[] key, byte[] data) throws Exception {
Cipher cipher = generateCbcCipher(ALGORITHM_NAME_CBC_PADDING, Cipher.ENCRYPT_MODE, key);
return cipher.doFinal(data);
}
private static Cipher generateCbcCipher(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, generateIV());
return cipher;
}
/**
* 加密模式之ECB
*
* @param key
* @param data
* @return
* @throws Exception
* @explain
*/
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);
}
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;
}
//生成iv
public static AlgorithmParameters generateIV() throws Exception {
//iv 为一个 16 字节的数组，这里采用和 iOS 端一样的构造方法，数据全为0
byte[] iv = new byte[16];
Arrays.fill(iv, (byte) 0x00);
System.out.println("generateIV"+ByteUtils.toHexString(iv));
AlgorithmParameters params = AlgorithmParameters.getInstance(ALGORITHM_NAME);
params.init(new IvParameterSpec(iv));
return params;
}
/**
* sm4解密_CBC
*
* @param hexKey 16进制密钥
* @param text 16进制的加密字符串（忽略大小写）
* @return 解密后的字符串
* @throws Exception
* @explain 解密模式：采用CBC
*/
public static String uncoverMsg_CBC(String hexKey, String text) throws Exception {
// 用于接收解密后的字符串
String result = "";
// hexString-->byte[]
byte[] keyData = ByteUtils.fromHexString(hexKey);
// hexString-->byte[]
byte[] resultData = ByteUtils.fromHexString(text);
// 解密
byte[] srcData = decrypt_Cbc_Padding(keyData, resultData);
// byte[]-->String
result = new String(srcData, ENCODING);
return result;
}
/**
* sm4解密_ECB
*
* @param hexKey 16进制密钥
* @param text 16进制的加密字符串（忽略大小写）
* @return 解密后的字符串
* @throws Exception
* @explain 解密模式：采用ECB
*/
public static String uncoverMsg_ECB(String hexKey, String text) throws Exception {
// 用于接收解密后的字符串
String result = "";
// hexString-->byte[]
byte[] keyData = ByteUtils.fromHexString(hexKey);
// hexString-->byte[]
byte[] resultData = ByteUtils.fromHexString(text);
// 解密
byte[] srcData = decrypt_Ecb_Padding(keyData, resultData);
// byte[]-->String
result = new String(srcData, ENCODING);
return result;
}
/**
* 解密
*
* @param key
* @param cipherText
* @return
* @throws Exception
* @explain
*/
public static byte[] decrypt_Cbc_Padding(byte[] key, byte[] cipherText) throws Exception {
Cipher cipher = generateCbcCipher(ALGORITHM_NAME_CBC_PADDING, Cipher.DECRYPT_MODE, key);
return cipher.doFinal(cipherText);
}
/**
* 解密
*
* @param key
* @param cipherText
* @return
* @throws Exception
* @explain
*/
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);
}
public static void main(String[] args) {
try {
String json = "openid=ooj0E5I8XR4AC5RnafNaZTwRhQn6";
System.out.println("加密前源数据————" + json);
// 生成32位16进制密钥
String key="0qig5udx3ntl8wci";
// key = SM4Utils.generateKeyString();
key=StringToHex.stringToHexString(key);
// System.out.println(key + "-----生成key");
String cipher = SM4Utils.protectMsg_ECB(key,json);
System.out.println("加密串---" + cipher);
json = SM4Utils.uncoverMsg_ECB(key, cipher);
System.out.println("解密后数据---" + json);
} catch (Exception e) {
e.printStackTrace();
}
}
}
SM4Utils工具类使用枚举
package xyz.diuut.pojo;
public enum BaseSmEnum {
/**
*
*/
ENCODING("UTF-8"),
ALGORITHM_NAME("SM4"),
ALGORITHM_NAME_CBC_PADDING("SM4/CBC/PKCS7Padding"),
ALGORITHM_NAME_ECB_PADDING("SM4/ECB/PKCS5Padding"),
;
private String msg;
BaseSmEnum(String msg) {
this.msg = msg;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
@Override
public String toString() {
return "BaseEnum{" +
"msg='" + msg + '\'' +
'}';
}
}
StringToHex工具类（部分对接提供的秘钥需转成hex才可以使用）
package xyz.diuut;
/**
* @Author Diuut
* @Date 2022/5/31 11:09
*/
public class StringToHex {
/**
* 字符串转换为16进制字符串
*
* @param s
* @return
*/
public static String stringToHexString(String s) {
String str = "";
for (int i = 0; i < s.length(); i++) {
int ch = s.charAt(i);
String s4 = Integer.toHexString(ch);
str = str + s4;
}
return str;
}
/**
* 16进制字符串转换为字符串
*
* @param s
* @return
*/
public static String hexStringToString(String s) {
if (s == null || s.equals("")) {
return null;
}
s = s.replace(" ", "");
byte[] baKeyword = new byte[s.length() / 2];
for (int i = 0; i < baKeyword.length; i++) {
try {
baKeyword[i] = (byte) (0xff & Integer.parseInt(
s.substring(i * 2, i * 2 + 2), 16));
} catch (Exception e) {
e.printStackTrace();
}
}
try {
s = new String(baKeyword, "gbk");
new String();
} catch (Exception e1) {
e1.printStackTrace();
}
return s;
}
/**
* 16进制表示的字符串转换为字节数组
*
* @param s 16进制表示的字符串
* @return byte[] 字节数组
*/
public static byte[] hexStringToByteArray(String s) {
int len = s.length();
byte[] b = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
// 两位一组，表示一个字节,把这样表示的16进制字符串，还原成一个字节
b[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4) + Character
.digit(s.charAt(i + 1), 16));
}
return b;
}
/**
* byte数组转16进制字符串
* @param bArray
* @return
*/
public static final String bytesToHexString(byte[] bArray) {
StringBuffer sb = new StringBuffer(bArray.length);
String sTemp;
for (int i = 0; i < bArray.length; i++) {
sTemp = Integer.toHexString(0xFF & bArray[i]);
if (sTemp.length() < 2) {
sb.append(0);
}
sb.append(sTemp.toUpperCase());
}
return sb.toString();
}
}
上面的内容都引入后工具类中有测试方法可以试下。暂时只用到了上面的东西，后面如果有其他用到的再补充。以上。