1、工具类RSAUtils.java
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.io.ByteArrayOutputStream;
import javax.crypto.Cipher;
import java.security.*;
import java.util.*;
public class RSAUtils {
/**
* 加密算法RSA
*/
public static final String KEY_ALGORITHM = "RSA";
/**
* 签名算法
*/
public static final String SIGNATURE_ALGORITHM = "SHA256withRSA";
/**
* 获取公钥的key
*/
private static final String PUBLIC_KEY_STR = "PublicKeyStr";
/**
* 获取私钥的key
*/
private static final String PRIVATE_KEY_STR = "PrivateKeyStr";
/**
* RSA最大加密明文大小(字节数)
*/
private static final int MAX_ENCRYPT_BLOCK = 117;
/**
* RSA最大解密密文大小(字节数)
*/
private static final int MAX_DECRYPT_BLOCK = 128;
/**
* @description: 生成公钥私钥
* @date: 2024/1/17 14:47
* @param
* @return java.util.Map<java.lang.String,java.lang.String>
*/
public static Map<String, String> initKeyPair() throws Exception {
KeyPairGenerator kpg = KeyPairGenerator.getInstance(KEY_ALGORITHM);
kpg.initialize(1024);
KeyPair keyPair = kpg.generateKeyPair();
PublicKey publicKey = keyPair.getPublic();
PrivateKey privateKey = keyPair.getPrivate();
String publicKeyStr = encryptBASE64(publicKey.getEncoded());
String privateKeyStr = encryptBASE64(privateKey.getEncoded());
Map<String, String> keyMap = new HashMap<>();
keyMap.put(PUBLIC_KEY_STR, publicKeyStr);
keyMap.put(PRIVATE_KEY_STR, privateKeyStr);
return keyMap;
}
/**
* @description: 公钥加密
* @date: 2024/1/17 14:49
* @param str 待加密字符串
* @param key 公钥
* @return java.lang.String
*/
public static String encryptByPublicKey(String str, String key) throws Exception {
byte[] data = str.getBytes();
PublicKey publicKey = strToPublicKey(key);
Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] bytes = dataSegment(data, cipher, MAX_ENCRYPT_BLOCK);
return encryptBASE64(bytes);
}
/**
* @description: 私钥解密
* @date: 2024/1/17 14:52
* @param str 待解密字符串
* @param key 私钥
* @return java.lang.String
*/
public static String decryptByPrivateKey(String str, String key) throws Exception {
byte[] data = decryptBASE64(str);
PrivateKey privateKey = strToPrivateKey(key);
Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, privateKey);
byte[] bytes = dataSegment(data, cipher, MAX_DECRYPT_BLOCK);
return new String(bytes);
}
/**
* @description: 私钥加密
* @date: 2024/1/17 14:58
* @param str 待加密字符串
* @param key 私钥
* @return java.lang.String
*/
public static String encryptByPrivateKey(String str, String key) throws Exception {
byte[] data = str.getBytes();
PrivateKey privateKey = strToPrivateKey(key);
Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
byte[] bytes = dataSegment(data, cipher, MAX_ENCRYPT_BLOCK);
return encryptBASE64(bytes);
}
/**
* @description: 公钥解密
* @date: 2024/1/17 15:23
* @param str 待解密字符串
* @param key 公钥
* @return java.lang.String
*/
public static String decryptByPublicKey(String str, String key) throws Exception {
byte[] data = decryptBASE64(str);
PublicKey publicKey = strToPublicKey(key);
Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, publicKey);
byte[] bytes = dataSegment(data, cipher, MAX_DECRYPT_BLOCK);
return new String(bytes);
}
/**
* @description: 使用私钥对数据进行数字签名
* @date: 2024/1/17 15:36
* @param str 待加签字符串
* @param privateKey 私钥
* @return java.lang.String
*/
public static String sign(String str, String privateKey) throws Exception {
byte[] data = str.getBytes();
PrivateKey priKey = strToPrivateKey(privateKey);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initSign(priKey);
signature.update(data);
byte[] bytes = signature.sign();
return encryptBASE64(bytes);
}
/**
* @description: 使用公钥对数据验证签名
* @date: 2024/1/17 15:46
* @param str 待验签字符串(即要加签的内容)
* @param publicKey 公钥
* @param sign 数据签名
* @return boolean
*/
public static boolean verify(String str, String publicKey, String sign) throws Exception {
byte[] data = str.getBytes();
byte[] signBytes = decryptBASE64(sign);
PublicKey pubKey = strToPublicKey(publicKey);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initVerify(pubKey);
signature.update(data);
return signature.verify(signBytes);
}
/**
* @description: 对数据进行分段加密或解密
* @date: 2024/1/17 16:11
* @param data
* @param cipher
* @param maxBlock
* @return byte[]
*/
private static byte[] dataSegment(byte[] data, Cipher cipher, int maxBlock) throws Exception{
byte[] toByteArray;
int inputLen = data.length;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
int i = 0;
byte[] cache;
// 对数据分段加密解密
while (inputLen - offSet > 0) {
int var = inputLen - offSet > maxBlock ? maxBlock : inputLen - offSet;
cache = cipher.doFinal(data, offSet, var);
out.write(cache, 0, cache.length);
i++;
offSet = i * maxBlock;
}
toByteArray = out.toByteArray();
out.close();
return toByteArray;
}
/**
* @description: 获取私钥
* @date: 2024/1/17 14:57
* @param str 私钥字符串
* @return java.security.PrivateKey
*/
private static PrivateKey strToPrivateKey(String str) throws Exception {
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(decryptBASE64(str));
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8KeySpec);
return privateKey;
}
/**
* @description: 获取公钥
* @date: 2024/1/17 14:57
* @param str 公钥字符串
* @return java.security.PrivateKey
*/
private static PublicKey strToPublicKey(String str) throws Exception {
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(decryptBASE64(str));
KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
PublicKey publicKey = keyFactory.generatePublic(x509KeySpec);
return publicKey;
}
/**
* @description: 字节数组转字符串
* @date: 2024/1/17 14:59
* @param bytes 字节数组
* @return java.lang.String
*/
private static String encryptBASE64(byte[] bytes) {
return Base64.getEncoder().encodeToString(bytes);
}
/**
* @description: 字符串转字节数组
* @date: 2024/1/17 15:00
* @param str 字符串
* @return byte[]
*/
private static byte[] decryptBASE64(String str) {
return Base64.getDecoder().decode(str);
}
public static void main(String[] args) throws Exception {
// 获取公钥私钥
Map<String, String> keyMap = initKeyPair();
String publicKey = keyMap.get(PUBLIC_KEY_STR);
String privateKey = keyMap.get(PRIVATE_KEY_STR);
System.out.println("公钥: " + publicKey);
System.out.println("私钥: " + privateKey);
String data = "123456";
System.out.println("源数据: " + data);
// 公钥加密私钥解密
String encryptData = encryptByPublicKey(data, publicKey);
String decryptData = decryptByPrivateKey(encryptData, privateKey);
System.out.println("公钥加密结果: " + encryptData);
System.out.println("私钥解密结果: " + decryptData);
System.out.println();
// 私钥加密公钥解密
String encryptData2 = encryptByPrivateKey(data, privateKey);
String decryptData2 = decryptByPublicKey(encryptData2, publicKey);
System.out.println("私钥加密结果: " + encryptData2);
System.out.println("公钥解密结果: " + decryptData2);
System.out.println();
// 私钥加签公钥验签
String data2 = "abc123369";
String sign = sign(data2, privateKey);
boolean flag = verify(data2, publicKey, sign);
System.out.println("私钥加签结果: " + sign);
System.out.println("公钥验签结果: " + flag);
}
}
2、测试结果
标签：return,String,RSA,param,str,验签,JAVA,byte,data From： https://www.cnblogs.com/guliang/p/17975428