「java.rsa」JAVArsa加密
今天给各位分享java.rsa的知识，其中也会对JAVArsa加密进行解释，如果能碰巧解决你现在面临的问题，别忘了关注本站，现在开始吧！
本文目录一览：
关于java中rsa的问题
【实例下载】本文介绍RSA2加密与解密，RSA2是RSA的加强版本，在密钥长度上采用2048, RSA2比RSA更安全，更可靠, 本人的另一篇文章RSA已经发表，有想了解的可以点开下面的RSA文章
Java中RSA的方式如何实现非对称加密的示例
代码如下，需要依赖一个jar包commons-codec-1.9.jar，用于Base64转换，请自行下载。
import org.apache.commons.codec.binary.Base64;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import java.io.ByteArrayOutputStream;
import java.io.UnsupportedEncodingException;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
public class RSAUtils {
// 加密方式
public static final String ALGORITHM = "RSA";
// 签名算法
private static final String SIGNATURE_ALGORITHM = "SHA1WithRSA";
// 创建密钥对初始长度
private static final int KEY_SIZE = 512;
// 字符编码格式
private static final String CHARSET = "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;
private KeyFactory keyFactory;
public RSAUtils() throws NoSuchAlgorithmException {
keyFactory = KeyFactory.getInstance(ALGORITHM);
}
/**
* 私钥加密
*
* @param content 待加密字符串
* @param privateKey 私钥
* @return 加密后字符串（BASE64编码）
*/
public String encryptByPrivateKey(String content, String privateKey) throws Exception {
String result;
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
byte[] keyBytes = new Base64().decode(privateKey);
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
PrivateKey pKey = keyFactory.generatePrivate(pkcs8KeySpec);
Cipher cipher = Cipher.getInstance(ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, pKey);
byte[] data = content.getBytes(CHARSET);
write2Stream(cipher, data, out);
byte[] resultBytes = out.toByteArray();
result = Base64.encodeBase64String(resultBytes);
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
/**
* 公钥解密
*
* @param content 已加密字符串（BASE64加密）
* @param publicKey 公钥
* @return
*/
public String decryptByPublicKey(String content, String publicKey) throws Exception {
String result = "";
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
byte[] keyBytes = new Base64().decode(publicKey);
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
PublicKey pKey = keyFactory.generatePublic(x509KeySpec);
Cipher cipher = Cipher.getInstance(ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, pKey);
byte[] data = Base64.decodeBase64(content);
write2Stream(cipher, data, out);
byte[] resultBytes = out.toByteArray();
result = new String(resultBytes);
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
/**
* 公钥加密
*
* @param content 待加密字符串
* @param publicKey 公钥
* @return 加密后字符串（BASE64编码）
*/
public String encryptByPublicKey(String content, String publicKey) throws Exception {
String result = "";
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
byte[] keyBytes = new Base64().decode(publicKey);
X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
PublicKey pKey = keyFactory.generatePublic(x509KeySpec);
Cipher cipher = Cipher.getInstance(ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, pKey);
byte[] data = content.getBytes(CHARSET);
write2Stream(cipher,
data, out);
byte[] resultBytes = out.toByteArray();
result = Base64.encodeBase64String(resultBytes);
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
/**
* 私钥解密
*
* @param content 已加密字符串
* @param privateKey 私钥
* @return 解密后字符串
*/
public String decryptByPrivateKey(String content, String privateKey) throws Exception {
String result = "";
try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
byte[] keyBytes = new Base64().decode(privateKey);
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
PrivateKey pKey = keyFactory.generatePrivate(pkcs8KeySpec);
Cipher cipher = Cipher.getInstance(ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, pKey);
byte[] data = Base64.decodeBase64(content);
write2Stream(cipher, data, out);
byte[] resultBytes = out.toByteArray();
result = new String(resultBytes);
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
private static void write2Stream(Cipher cipher, byte[] data, ByteArrayOutputStream out) throws
BadPaddingException, IllegalBlockSizeException {
int dataLen = data.length;
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段解密
while (dataLen - offSet 0) {
if (dataLen - offSet MAX_DECRYPT_BLOCK) {
cache = cipher.doFinal(data, offSet, MAX_DECRYPT_BLOCK);
} else {
cache = cipher.doFinal(data, offSet, dataLen - offSet);
}
out.write(cache, 0, cache.length);
i++;
offSet = i * MAX_DECRYPT_BLOCK;
}
}
/**
* 用私钥对信息生成数字签名
*
* @param data 已加密数据
* @param privateKey 私钥(BASE64编码)
* @return sign
*/
public String sign(String data, String privateKey) throws Exception {
String result = "";
try {
byte[] keyBytes = new Base64().decode(privateKey);
PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initSign(privateK);
signature.update(parse2HexStr(data).getBytes(CHARSET));
result = new Base64().encodeToString(signature.sign());
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
/**
* 校验数字签名
*
* @param data 已加密数据
* @param publicKey 公钥(BASE64编码)
* @param sign 数字签名
* @return
* @throws Exception
*/
public boolean verify(String data, String publicKey, String sign) throws Exception {
boolean result;
try {
byte[] keyBytes = new Base64().decode(publicKey);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
PublicKey publicK = keyFactory.generatePublic(keySpec);
Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
signature.initVerify(publicK);
signature.update(parse2HexStr(data).getBytes(CHARSET));
result = signature.verify(new Base64().decode(sign));
} catch (Exception e) {
throw new Exception(e);
}
return result;
}
/**
* 将二进制转换成16进制
*
* @param data
* @return
*/
public static String parse2HexStr(String data) throws Exception {
String result = "";
try {
byte[] buf = data.getBytes(CHARSET);
StringBuffer sb = new StringBuffer();
for (int i = 0; i buf.length; i++) {
String hex = Integer.toHexString(buf[i] 0xFF);
if (hex.length() == 1) {
hex = '0' + hex;
}
sb.append(hex.toUpperCase());
}
result = sb.toString();
} catch (UnsupportedEncodingException e) {
throw new Exception(e);
}
return result;
}
/**
* 生成公钥与私钥
*/
public static void createKey() throws Exception {
try {
KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(ALGORITHM);
keyPairGenerator.initialize(KEY_SIZE);
KeyPair keyPair = keyPairGenerator.generateKeyPair();
RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
String publicKey = Base64.encodeBase64String(rsaPublicKey.getEncoded());
String privateKey = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
System.out.println("publicKey=" + publicKey + "\nprivateKey=" + privateKey);
} catch (NoSuchAlgorithmException e) {
throw new Exception(e);
}
}
public static void main(String[] args) throws Exception {
String PRIVATE_KEY = "MIICeAIBADANBgkqhkiG9w0BAQEFAASCAmIwggJeAgEAAoGBAKeYGXH6Vz+m+KuL11RDRaNdHB4YQeZgqpJGPRSwBelgvEoHu2/fNs1bmgfJhI8lhr/o/Hy8EFB/I/DDyLcCcU4bCLtxpki8edC+KJR2WvyYfnVmWEe/3q2jSVKRf81868q9Cd3MMfrQPMsY4x0TQ0GtOf/nMSMbAltV2W8J86IfAgMBAAECgYEApYu4lr2SMW3ddJZNvQ42W4g9nfyYG9igpJx8+VJmhIDpfLbmjzsOBwvUupx0NHH9CNQ7k3qxItJzzf+W5C+lesEOAqdO5nahRZsL8BIDoxTEn2j+1GXkzQw3vqPY50xqRnZsoP5TyNNsOM7KYaOoz4VFMdVIFwoT3OKM5z7mxgECQQD51r17WZDSa/kucaH7gCOePxJPS6Ust0eVd5tBOMpFzD/VtziogSIWyhGKkLH0SyTJEe91CCpdpxufLSZgIiN5AkEAq7ojtvU4twak1N1/1qX+t8f5wD8i/8GU702PeCwkGI5ymrARq+W2yCuvU1bouXBhjKHV4KhafKYixdHUMg00VwJAYVUjpLaUESY3gbyLWqvlNHVl8LaLtwwAO17JgXNaei7Ef8JNtHf6i95VTyJn8cCEqEDwhSuVNb8wp6azWKh0IQJBAJHrcT2d0bt0IcvfCynRk0eG3WnGPG8mhu9w8GAk4ecb47YdtmZio5YjyK8AQnCQVdOyEJL9eyY/5XxCeBSvs7ECQQCKQ2f5HLDkkHvc6rlaHCJmqNRCS+CxhoaiaSPYLAac7WXmb614ACLECc86C/nkefTq0SNpUDVbGxVpJi9/FOUf";
String PUBLIC_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCnmBlx+lc/pviri9dUQ0WjXRweGEHmYKqSRj0UsAXpYLxKB7tv3zbNW5oHyYSPJYa/6Px8vBBQfyPww8i3AnFOGwi7caZIvHnQviiUdlr8mH51ZlhHv96to0lSkX/NfOvKvQndzDH60DzLGOMdE0NBrTn/5zEjGwJbVdlvCfOiHwIDAQAB";
RSAUtils rsaUtil = new RSAUtils();
String encryptByPublicKey = rsaUtil.encryptByPublicKey("你好！", PUBLIC_KEY);
System.out.println(encryptByPublicKey);
String decryptByPrivateKey = rsaUtil.decryptByPrivateKey(encryptByPublicKey, PRIVATE_KEY);
System.out.println(decryptByPrivateKey);
String encryptByPrivateKey = rsaUtil.encryptByPrivateKey("你好！", PRIVATE_KEY);
System.out.println(encryptByPrivateKey);
String decryptByPublicKey = rsaUtil.decryptByPublicKey(encryptByPrivateKey, PUBLIC_KEY);
System.out.println(decryptByPublicKey);
String sign = rsaUtil.sign("1234", PRIVATE_KEY);
System.out.println("sign:" + sign);
System.out.println(rsaUtil.verify("1234", PUBLIC_KEY, sign));
}
}
Java RSA解密
根据已知的公钥m与e生成PublicKey，然后加密，需要用到bouncycastle这个库，大致代码如下：
// 生成m与e
byte[] mBytes = Hex.decode("C535AD4F...略");
BigInteger m = new BigInteger(1, mBytes);
BigInteger e = BigInteger.valueOf(0x10001);
// 恢复公钥
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(new RSAPublicKeySpec(m, e));
/* 根据经验，那个JS加密后的密文用Java解出来是反转的字符串，
* 所以如果想要达到与JS完全一致的效果的话，需要将明文先反转，
* 即将 "admin" 变成 "nimda"
*/
byte[] data = new StringBuilder("admin").reverse().toString().getBytes();
// 现在可以用publicKey加密了
Cipher cipher = Cipher.getInstance("RSA", new BouncyCastleProvider());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] enc = cipher.doFinal(data);
System.out.println(Hex.toHexString(enc));
理论上代码大概是这样。加密结果是：
0d42e0ab31391a536346a1a1af7696e21734ab6004b33f4ce1add778d0c3b8b93141cf0422ef3e086e41d0dcf96c9908e30dd9b993c1eea0d0a392f2ecf4347e5ed7d9b3451796ef04203248536ebca02120a9c3fa520f88ca43ec0df30d2210026ac98e0dcd460bd3bd38b4ddd30a5fe0a0c103a5bd02b2e7eb9ae3a2ddab68
关于java.rsa和JAVArsa加密的介绍到此就结束了，不知道你从中找到你需要的信息了吗 ？如果你还想了解更多这方面的信息，记得收藏关注本站。
发布于：2022-11-22，除非注明，否则均为原创文章，转载请注明出处。