RSATest.java

package com.timliu.security.asymmetric_encryption;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;
import javax.crypto.KeyAgreement;
import javax.crypto.SecretKey;
import javax.crypto.interfaces.DHPublicKey;
import javax.crypto.spec.DHParameterSpec;

import org.apache.commons.codec.binary.Base64;

import com.sun.org.apache.xalan.internal.utils.Objects;

public class RSATest 
{
	public static final String src = "rsa test";

	public static void main(String[] args) 
	{
		jdkRSA();

	}
	
	// jdk实现：
	public static void jdkRSA()
	{		
		try 
		{
			// 1.初始化发送方密钥
			KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
			keyPairGenerator.initialize(512);
			KeyPair keyPair = keyPairGenerator.generateKeyPair();
			RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
			RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
			System.out.println("Public Key:" + Base64.encodeBase64String(rsaPublicKey.getEncoded()));
			System.out.println("Private Key:" + Base64.encodeBase64String(rsaPrivateKey.getEncoded()));
			
			// 2.私钥加密、公钥解密 ---- 加密
			PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
			KeyFactory keyFactory = KeyFactory.getInstance("RSA");
			PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
			Cipher cipher = Cipher.getInstance("RSA");
			cipher.init(Cipher.ENCRYPT_MODE, privateKey);
			byte[] result = cipher.doFinal(src.getBytes());
			System.out.println("私钥加密、公钥解密 ---- 加密:" + Base64.encodeBase64String(result));
			
			// 3.私钥加密、公钥解密 ---- 解密
			X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
			keyFactory = KeyFactory.getInstance("RSA");
			PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
			cipher = Cipher.getInstance("RSA");
			cipher.init(Cipher.DECRYPT_MODE, publicKey);
			result = cipher.doFinal(result);
			System.out.println("私钥加密、公钥解密 ---- 解密:" + new String(result));
			
			
			
			// 4.公钥加密、私钥解密 ---- 加密
			X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
			KeyFactory keyFactory2 = KeyFactory.getInstance("RSA");
			PublicKey publicKey2 = keyFactory2.generatePublic(x509EncodedKeySpec2);
			Cipher cipher2 = Cipher.getInstance("RSA");
			cipher2.init(Cipher.ENCRYPT_MODE, publicKey2);
			byte[] result2 = cipher2.doFinal(src.getBytes());
			System.out.println("公钥加密、私钥解密 ---- 加密:" + Base64.encodeBase64String(result2));
			
			// 5.私钥解密、公钥加密 ---- 解密
			PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
			KeyFactory keyFactory5 = KeyFactory.getInstance("RSA");
			PrivateKey privateKey5 = keyFactory5.generatePrivate(pkcs8EncodedKeySpec5);
			Cipher cipher5 = Cipher.getInstance("RSA");
			cipher5.init(Cipher.DECRYPT_MODE, privateKey5);
			byte[] result5 = cipher5.doFinal(result2);
			System.out.println("公钥加密、私钥解密 ---- 解密:" + new String(result5));
			
		} catch (Exception e) {
			
			e.printStackTrace();
		}
		
	}

}