文章目录
常规加密：
java
package com.xiaolu;
import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.nio.charset.Charset;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.*;
public class RSAUtil {
public static final String SIGN_ALGORITHMS = "SHA256WithRSA";
public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
/** */
/**
* RSA最大加密明文大小
*/
private static final int MAX_ENCRYPT_BLOCK = 117;
/** */
/**
* RSA最大解密密文大小
*/
private static final int MAX_DECRYPT_BLOCK = 128;
public static KeyPair getKeyPair() throws Exception {
KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
generator.initialize(1024);
return generator.generateKeyPair();
}
/**
* 签名
*
* @param content
* @param privateKey
* @return
*/
public static String sign(String content, String privateKey) {
try {
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKey));
KeyFactory keyf = KeyFactory.getInstance("RSA");
PrivateKey priKey = keyf.generatePrivate(priPKCS8);
Signature signature = Signature.getInstance(SIGN_ALGORITHMS);
signature.initSign(priKey);
signature.update(content.getBytes(DEFAULT_CHARSET));
byte[] signed = signature.sign();
return Base64.getEncoder().encodeToString(signed);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 验签
*
* @param content
* @param sign
* @param publicKey
* @return
*/
public static boolean verify(String content, String sign, String publicKey) {
try {
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
byte[] encodedKey = Base64.getDecoder().decode(publicKey);
PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));
Signature signature = Signature.getInstance(SIGN_ALGORITHMS);
signature.initVerify(pubKey);
signature.update(content.getBytes(DEFAULT_CHARSET));
return signature.verify(Base64.getDecoder().decode(sign));
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
public static PublicKey getPublicKey(String key) throws Exception {
byte[] keyBytes = Base64.getDecoder().decode(key);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(keySpec);
return publicKey;
}
public static PrivateKey getPrivateKey(String key) throws Exception {
byte[] keyBytes = Base64.getDecoder().decode(key);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
return privateKey;
}
/**
* 公钥分段加密
*
* @param content
* @param publicKeyStr
* @return
* @throws Exception
*/
public static String publicEncrpyt(String content, String publicKeyStr) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(1, getPublicKey(publicKeyStr));
byte[] bytes = content.getBytes(DEFAULT_CHARSET);
int inputLen = bytes.length;
int offSet = 0;
byte[] cache;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int i = 0;
// 对数据分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
cache = cipher.doFinal(bytes, offSet, MAX_ENCRYPT_BLOCK);
} else {
cache = cipher.doFinal(bytes, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_ENCRYPT_BLOCK;
}
byte[] encryptedData = out.toByteArray();
out.close();
return Base64.getEncoder().encodeToString(encryptedData);
}
/**
* 私钥分段加密
*
* @param content
* @param privateKeyStr
* @return
* @throws Exception
*/
public static String privateEncrpyt(String content, String privateKeyStr) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(1, getPrivateKey(privateKeyStr));
byte[] bytes = content.getBytes(DEFAULT_CHARSET);
int inputLen = bytes.length;
int offSet = 0;
byte[] cache;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int i = 0;
// 对数据分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
cache = cipher.doFinal(bytes, offSet, MAX_ENCRYPT_BLOCK);
} else {
cache = cipher.doFinal(bytes, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_ENCRYPT_BLOCK;
}
byte[] encryptedData = out.toByteArray();
out.close();
return Base64.getEncoder().encodeToString(encryptedData);
}
/**
* 私钥分段解密
*
* @param content
* @param privateKeyStr
* @return
* @throws Exception
*/
public static String privateDecrypt(String content, String privateKeyStr) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(2, getPrivateKey(privateKeyStr));
byte[] bytes = Base64.getDecoder().decode(content);
int inputLen = bytes.length;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段解密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
cache = cipher.doFinal(bytes, offSet, MAX_DECRYPT_BLOCK);
} else {
cache = cipher.doFinal(bytes, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_DECRYPT_BLOCK;
}
byte[] decryptedData = out.toByteArray();
out.close();
return new String(decryptedData);
}
/**
* 公钥分段解密
*
* @param content
* @param publicKeyStr
* @return
* @throws Exception
*/
public static String publicDecrypt(String content, String publicKeyStr) throws Exception {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(2, getPublicKey(publicKeyStr));
byte[] bytes = Base64.getDecoder().decode(content);
int inputLen = bytes.length;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段解密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
cache = cipher.doFinal(bytes, offSet, MAX_DECRYPT_BLOCK);
} else {
cache = cipher.doFinal(bytes, offSet, inputLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_DECRYPT_BLOCK;
}
byte[] decryptedData = out.toByteArray();
out.close();
return new String(decryptedData);
}
public static void main(String[] args) throws Exception {
String content = "SYxxkj123@";
// 公钥216
String publicKey ="MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDaLRe493205T6+xpTqD3q2xtLEut8GPS6ter1mp507S8MutmRJ8mn8oBykNVFz8ZKCsOGI1UJZS2jNpEBOuCTu7GXZ/uTCBmLDigS5rG3YzlMkg0EdnyKxTRRLjoPUyIWSVKGZlU5VC/zBvB03qKZ3HpzHZHxGG/3z6E8aoXoPRwIDAQAB";
//私钥844
// String privateKey ="";
String s = publicEncrpyt(content, publicKey);
System.out.println("公钥加密后"+s);
}
}分段加密
java
package com.xiaolu;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import javax.crypto.Cipher;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
public class Demo {
public static BASE64Encoder base64Encoder = new BASE64Encoder();
public static BASE64Decoder base64Decoder = new BASE64Decoder();
// 公钥216
private static String publicKeyStr ="MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCCaGn5+Yq9o7kxmDS2zwIREIEkcpKbx44uPT/PX22XOjgzkMvbCEamu7KyatNhkrrSH6E14l1F739WztXffJ/OCXUmgF4egMedyGCA8ymZWbzyhwnZcywa8me8S2rjb3gkCD6VFq8BSPJx9vaMvlR7eZxe1O5lllaV6tE6SlNY7QIDAQAB";
//私钥844
private static String privateKeyStr =
"MIICdgIBADANBgkqhkiG9w0BAQEFAASCAmAwggJcAgEAAoGBAIJoafn5ir2juTGYNLbPAhEQgSRy" +
"kpvHji49P89fbZc6ODOQy9sIRqa7srJq02GSutIfoTXiXUXvf1bO1d98n84JdSaAXh6Ax53IYIDz" +
"KZlZvPKHCdlzLBryZ7xLauNveCQIPpUWrwFI8nH29oy+VHt5nF7U7mWWVpXq0TpKU1jtAgMBAAEC" +
"gYBOzKsk+s4EM5dnSXKo+ENmblOq43SFnzrh4+7X7vD4zZxCRH96NfEDNS4Qs45RSmmLKMOwHL2B" +
"0etfWBJSPisNZomhOBgTSfvHDSIFNbvVFqQBH5zEtxIB3bPrkW5X6EDF2BYCatC70Al21kmzHr2d" +
"BaL/c2p/4ueTdna/zKSKwQJBAMZLvFeyLi9jiIXXUzv7AkxF4SICtOOL56mKMkVlAXOWQgQe9FVs" +
"O8lTTK6GqqLrYe5cqgTiQqcLCP8/5n33oF0CQQCoW0ospTg8JEqStTmwemF8HfgxLU6YGj5kegD2" +
"Fq6HfCTq/z59THohbq6l+yoSxO3mjZb+7Zv1zu6oDR7YXFHRAkB66dEaDtFAAJNMWxc107Yt7xbI" +
"zSKw9TSoy4ezqhNHQXk0MrfDB27bsS2T9NdqWzr91CRzGIi2IEn4ZfSKWmblAkB2S1bOEfV2hMWF" +
"WiND9mnDDUfUPhKIW4BVl0hPodZWSouiN2DQJ8l07lF3PQjuEUNcCUb8rzYzvIgCut1eh1fRAkEA" +
"qBOEqBuRq9W7vrBlHbqEk1EXu2MfeRLZWljZn6uoyedJCdSh+6neUUvqHDGi3DNdss/ByWHI9e+9" +
"zOXTURmMaQ==";
private static RSAUtil ourInstance = new RSAUtil();
public static RSAUtil getInstance() {
return ourInstance;
}
// 生成密钥对
private static void generateKeyPair() throws NoSuchAlgorithmException {
KeyPairGenerator keyPairGenerator;
keyPairGenerator = KeyPairGenerator.getInstance("RSA");
keyPairGenerator.initialize(1024);
KeyPair keyPair = keyPairGenerator.generateKeyPair();
// 获取公钥，并以base64格式打印出来
PublicKey publicKey = keyPair.getPublic();
publicKeyStr = new String(base64Encoder.encode(publicKey.getEncoded()));
System.out.println("公钥:"+publicKeyStr);
// 获取私钥，并以base64格式打印出来
PrivateKey privateKey = keyPair.getPrivate();
privateKeyStr = new String(base64Encoder.encode(privateKey.getEncoded()));
System.out.println("私钥:"+privateKeyStr);
}
// 将base64编码后的公钥字符串转成PublicKey实例
private static PublicKey getPublicKey(String publicKey) throws Exception {
byte[] keyBytes = base64Decoder.decodeBuffer(publicKey);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
return keyFactory.generatePublic(keySpec);
}
// 将base64编码后的私钥字符串转成PrivateKey实例
private static PrivateKey getPrivateKey(String privateKey) throws Exception {
byte[] keyBytes = base64Decoder.decodeBuffer(privateKey);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
return keyFactory.generatePrivate(keySpec);
}
// 私钥加密
public static String encryptByPrivateKey(String content) throws Exception {
// 获取私钥
PrivateKey privateKey = getPrivateKey(privateKeyStr);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
byte[] cipherText = cipher.doFinal(content.getBytes());
String cipherStr = base64Encoder.encode(cipherText);
return cipherStr;
}
// 私钥解密
public static String decryptByPrivateKey(String content) throws Exception {
// 获取私钥
PrivateKey privateKey = getPrivateKey(privateKeyStr);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
byte[] cipherText = base64Decoder.decodeBuffer(content);
byte[] decryptText = cipher.doFinal(cipherText);
return new String(decryptText);
}
// 公钥加密
public static String encryptByPublicKey(String content) throws Exception {
// 获取公钥
PublicKey publicKey = getPublicKey(publicKeyStr);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] cipherText = cipher.doFinal(content.getBytes());
String cipherStr = base64Encoder.encode(cipherText);
return cipherStr;
}
// 公钥解密
public static String decryptByPublicKey(String content) throws Exception {
// 获取公钥
PublicKey publicKey = getPublicKey(publicKeyStr);
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, publicKey);
byte[] cipherText = base64Decoder.decodeBuffer(content);
byte[] decryptText = cipher.doFinal(cipherText);
return new String(decryptText);
}
public static void main(String[] args) throws Exception {
String data="SYxxkj123@";
System.out.println("初始数据："+data);
// 公钥加密
String encryptedBytes = encryptByPublicKey(data);
System.out.println("公钥加密后：" + encryptedBytes);
// // 私钥解密
// String decryptedBytes = decryptByPrivateKey(encryptedBytes);
//
// System.out.println("私钥解密后：" + decryptedBytes);
// // 私钥加密
// String encryptedBytes2 = encryptByPrivateKey(data);
// System.out.println("私钥加密后：" + encryptedBytes2);
// // 公钥解密
// String decryptedBytes2 = decryptByPublicKey(encryptedBytes2);
// System.out.println("公钥解密后：" + decryptedBytes2);
generateKeyPair();
}
}