「rsa算法java」rsa算法java scanner

admin 2023-03-19 18:43:08 397

今天给各位分享rsa算法java的知识，其中也会对rsa算法java scanner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：

1、如何用java实现128位密钥的RSA算法
2、java rsa私钥加密
3、java RSA算法实现256位密钥怎么做
4、关于java中rsa的问题
5、Java通过RSA算法获取公私钥对将公钥提供出去如何获取字符串的公钥

如何用java实现128位密钥的RSA算法

import javax.crypto.Cipher;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.security.Key;

import java.security.KeyPair;

import java.security.KeyPairGenerator;

import java.security.SecureRandom;

public class RSA_Encrypt {

/** 指定加密算法为DESede */

private static String ALGORITHM = "RSA";

/** 指定key的大小 */

private static int KEYSIZE = 128;

/** 指定公钥存放文件 */

private static String PUBLIC_KEY_FILE = "PublicKey";

/** 指定私钥存放文件 */

private static String PRIVATE_KEY_FILE = "PrivateKey";

// private static String PUBLIC_KEY_FILE = "D://PublicKey.a";

// private static String PRIVATE_KEY_FILE = "D://PrivateKey.a";

/**

* 生成密钥对

private static void generateKeyPair() throws Exception{

/** RSA算法要求有一个可信任的随机数源 */

SecureRandom sr = new SecureRandom();

/** 为RSA算法创建一个KeyPairGenerator对象 */

KeyPairGenerator kpg = KeyPairGenerator.getInstance(ALGORITHM);

/** 利用上面的随机数据源初始化这个KeyPairGenerator对象 */

kpg.initialize(KEYSIZE, sr);

/** 生成密匙对 */

KeyPair kp = kpg.generateKeyPair();

/** 得到公钥 */

Key publicKey = kp.getPublic();

/** 得到私钥 */

Key privateKey = kp.getPrivate();

/** 用对象流将生成的密钥写入文件 */

ObjectOutputStream oos1 = new ObjectOutputStream(new FileOutputStream(PUBLIC_KEY_FILE));

ObjectOutputStream oos2 = new ObjectOutputStream(new FileOutputStream(PRIVATE_KEY_FILE));

oos1.writeObject(publicKey);

oos2.writeObject(privateKey);

/** 清空缓存，关闭文件输出流 */

oos1.close();

oos2.close();

}

/**

* 加密方法

* source：源数据

public static String encrypt(String source) throws Exception{

generateKeyPair();

/** 将文件中的公钥对象读出 */

ObjectInputStream ois = new ObjectInputStream(new FileInputStream(PUBLIC_KEY_FILE));

Key key = (Key) ois.readObject();

ois.close();

/** 得到Cipher对象来实现对源数据的RSA加密 */

Cipher cipher = Cipher.getInstance(ALGORITHM);

cipher.init(Cipher.ENCRYPT_MODE, key);

byte[] b = source.getBytes();

/** 执行加密操作 */

byte[] b1 = cipher.doFinal(b);

BASE64Encoder encoder = new BASE64Encoder();

return encoder.encode(b1);

}

/**

* 解密算法

* cryptograph:密文

public static String decrypt(String cryptograph) throws Exception{

/** 将文件中的私钥对象读出 */

ObjectInputStream ois = new ObjectInputStream(new FileInputStream(PRIVATE_KEY_FILE));

Key key = (Key) ois.readObject();

/** 得到Cipher对象对已用公钥加密的数据进行RSA解密 */

Cipher cipher = Cipher.getInstance(ALGORITHM);

cipher.init(Cipher.DECRYPT_MODE, key);

BASE64Decoder decoder = new BASE64Decoder();

byte[] b1 = decoder.decodeBuffer(cryptograph);

/** 执行解密操作 */

byte[] b = cipher.doFinal(b1);

return new String(b);

}

public static void main(String[] args) {

try {

String source = "Hello World!";//要加密的字符串

String cryptograph = encrypt(source);

System.out.println(cryptograph);

String target = decrypt(cryptograph);//解密密文

System.out.println(target);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}//生成的密文

}

java rsa私钥加密

java rsa私钥加密是什么？让我们一起来了解一下吧！

java rsa私钥加密是一种加密算法。私钥加密算法是用私钥来进行加密与解密信息。私钥加密也被称作对称加密，原因是加密与解密使用的秘钥是同一个。

RSA加密需要注意的事项如下：

1. 首先产生公钥与私钥

2. 设计加密与解密的算法

3. 私钥加密的数据信息只能由公钥可以解密

4. 公钥加密的数据信息只能由私钥可以解密

实战演练，具体步骤如下： public class RsaCryptTools { private static final String CHARSET = "utf-8"; private static final Base64.Decoder decoder64 = Base64.getDecoder(); private static final Base64.Encoder encoder64 = Base64.getEncoder(); /** * 生成公私钥 * @param keySize * @return * @throws NoSuchAlgorithmException */ public static SecretKey generateSecretKey(int keySize) throws NoSuchAlgorithmException { //生成密钥对 KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA"); keyGen.initialize(keySize, new SecureRandom()); KeyPair pair = keyGen.generateKeyPair(); PrivateKey privateKey = pair.getPrivate(); PublicKey publicKey = pair.getPublic(); //这里可以将密钥对保存到本地 return new SecretKey(encoder64.encodeToString(publicKey.getEncoded()), encoder64.encodeToString(privateKey.getEncoded())); } /** * 私钥加密 * @param data * @param privateInfoStr * @return * @throws IOException * @throws InvalidCipherTextException */ public static String encryptData(String data, String privateInfoStr) throws IOException, InvalidKeySpecException, NoSuchAlgorithmException, InvalidKeyException, NoSuchPaddingException, BadPaddingException, IllegalBlockSizeException { Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding"); cipher.init(Cipher.ENCRYPT_MODE, getPrivateKey(privateInfoStr)); return encoder64.encodeToString(cipher.doFinal(data.getBytes(CHARSET))); } /** * 公钥解密 * @param data * @param publicInfoStr * @return */ public static String decryptData(String data, String publicInfoStr) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeySpecException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, UnsupportedEncodingException { byte[] encryptDataBytes=decoder64.decode(data.getBytes(CHARSET)); //解密 Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding"); cipher.init(Cipher.DECRYPT_MODE, getPublicKey(publicInfoStr)); return new String(cipher.doFinal(encryptDataBytes), CHARSET); } private static PublicKey getPublicKey(String base64PublicKey) throws NoSuchAlgorithmException, InvalidKeySpecException { X509EncodedKeySpec keySpec = new X509EncodedKeySpec(Base64.getDecoder().decode(base64PublicKey.getBytes())); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); return keyFactory.generatePublic(keySpec); } private static PrivateKey getPrivateKey(String base64PrivateKey) throws NoSuchAlgorithmException, InvalidKeySpecException { PrivateKey privateKey = null; PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(base64PrivateKey.getBytes())); KeyFactory keyFactory = null; keyFactory = KeyFactory.getInstance("RSA"); privateKey = keyFactory.generatePrivate(keySpec); return privateKey; } /** * 密钥实体 * @author hank * @since 2020/2/28 0028 下午 16:27 */ public static class SecretKey { /** * 公钥 */ private String publicKey; /** * 私钥 */ private String privateKey; public SecretKey(String publicKey, String privateKey) { this.publicKey = publicKey; this.privateKey = privateKey; } public String getPublicKey() { return publicKey; } public void setPublicKey(String publicKey) { this.publicKey = publicKey; } public String getPrivateKey() { return privateKey; } public void setPrivateKey(String privateKey) { this.privateKey = privateKey; } @Override public String toString() { return "SecretKey{" + "publicKey='" + publicKey + '\'' + ", privateKey='" + privateKey + '\'' + '}'; } } private static void writeToFile(String path, byte[] key) throws IOException { File f = new File(path); f.getParentFile().mkdirs(); try(FileOutputStream fos = new FileOutputStream(f)) { fos.write(key); fos.flush(); } } public static void main(String[] args) throws NoSuchAlgorithmException, NoSuchPaddingException, IOException, BadPaddingException, IllegalBlockSizeException, InvalidKeyException, InvalidKeySpecException { SecretKey secretKey = generateSecretKey(2048); System.out.println(secretKey); String enStr = encryptData("你好测试测试", secretKey.getPrivateKey()); System.out.println(enStr); String deStr = decryptData(enStr, secretKey.getPublicKey()); System.out.println(deStr); enStr = encryptData("你好测试测试hello", secretKey.getPrivateKey()); System.out.println(enStr); deStr = decryptData(enStr, secretKey.getPublicKey()); System.out.println(deStr); } }

java RSA算法实现256位密钥怎么做

参考下面代码：

try {

KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA",

new org.bouncycastle.jce.provider.BouncyCastleProvider());

final int KEY_SIZE = 128;// 没什么好说的了，这个值关系到块加密的大小，可以更改，但是不要太大，否则效率会低

keyPairGen.initialize(KEY_SIZE, new SecureRandom());

KeyPair keyPair = keyPairGen.generateKeyPair();

return keyPair;

} catch (Exception e) {

throw new Exception(e.getMessage());

}

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通过RSA算法获取公私钥对将公钥提供出去如何获取字符串的公钥

直接将公匙BYTE数组转换为16进制的串啊

private static char hexTable[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};

public static String toHexString(byte bytes[])

{

StringBuilder sb = new StringBuilder();

for (int i = 0; i bytes.length; i++)

{

char chars[] = new char[2];

int d = (bytes[i] 240) 4;

int m = bytes[i] 15;

chars[0] = hexTable[d];

chars[1] = hexTable[m];

sb.append(chars);

}

return sb.toString();

}

rsa算法java的介绍就聊到这里吧，感谢你花时间阅读本站内容，更多关于rsa算法java scanner、rsa算法java的信息别忘了在本站进行查找喔。

标签：rsa算法java