Detailed explanation of Java's method of implementing RSA algorithm

This article describes the method of implementing RSA algorithm in Java. Share it for your reference, as follows:

One introduction

The only widely accepted and implemented for data encryption and digital signature public key encryption, private key decryption private key encryption, public key decryption

Two RSA parameter description

Three realizations

 package com.imooc.security.rsa;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 org.apache.commons.codec.binary.Base64;public class ImoocRSA { private static String src = "cakin24 security rsa"; public static void main(String[] args) { jdkRSA(); } public static void jdkRSA() { try { //1. Initialization key 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. Private key encryption, public key decryption--encryption 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("Private key encryption, public key decryption-encryption: " + Base64.encodeBase64String(result)); //3. Private key encryption, public key decryption-decryption-decryption 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("Private key encryption, public key decryption-decryption: " + new String(result)); //4. Public key encryption, private key decryption-encryption x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded()); keyFactory = KeyFactory.getInstance("RSA"); publicKey = keyFactory.generatePublic(x509EncodedKeySpec); cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.ENCRYPT_MODE, publicKey); result = cipher.doFinal(src.getBytes()); System.out.println("Public key encryption, private key decryption-encryption: " + Base64.encodeBase64String(result)); //5. Public key encryption, private key decryption-decryption-pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded()); keyFactory = KeyFactory.getInstance("RSA"); privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec); cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.DECRYPT_MODE, privateKey); result = cipher.doFinal(result); System.out.println("Public key encryption, private key decryption-decryption: " + new String(result)); } catch (Exception e) { e.printStackTrace(); } }}

Four realization effects

Public Key: MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAJcBeOb97IdkkirBmx3MOY5e4eRwh0uvC2BcNlY1rDo0lZ8ibR1bl1RJXWkHv7U0ASO/5DBlnnnGbQRtsJlsCPMCAwEAQ==
Private Key: MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAlwF45v3sh2SSKsGbHcw5jl7h5HCHS68LYFw2VjWsOjSVnyJtHVuXVEldaQe/tTQBI7/kMGWeecZtBG2wmWwI8wIDAQABAkAdSkPRSl+ew3s2n+cemIZxfyYB0XHs1D84qapAfpixkUNvWL0A4ovrwsnwt4MEjAtWVTufNvTxIZcZdx+Q5DbBAi EA9TzzYMGRU+3mdlAx0ICF+NIqwvlqyvedKa4KSx55gVUCIQCdoeX6mqGRP78aQjYKWeogwliszjU5fN/LFvKZrcgBJwIhAMvbBLzzaykHY0IKW75kd/lkSyOUTY+20bAp+miDRqGZAiA6r36eeRkzqUbtcL8LxYPb5F79HtxD5dCvnIB/ZGp0uwIgWtXI7IxHjYCsNomSJdu1J3dU9KqQuW/eOHxrk/OgUYE=
Private key encryption, public key decryption - Encryption: VjkFsOiVeLvKES5RprhsJK9tdTzohdELLS7yluidCYEe7DkuCM9srj8kwadynHI4M0oLAfJhK6447hp7Ia8x7A==
Private key encryption, public key decryption - decryption: cakin24 security rsa
Public key encryption, private key decryption - encryption: gAWl73UxHtO+EfKkpmfMdhtK0Vh7HB8n+30l1Hp8aAMIagD21h2x/q/Ns+soGsOXNovuNzaSGZenmZzcjB4VEA==
Public key encryption, private key decryption - decryption: cakin24 security rsa

Five application scenarios

PS: Friends who are interested in encryption and decryption can also refer to the online tools of this site:

Online RSA encryption/decryption tools:
http://tools.VeVB.COM/password/rsa_encode

Text online encryption and decryption tools (including AES, DES, RC4, etc.):
http://tools.VeVB.COM/password/txt_encode

MD5 online encryption tool:
http://tools.VeVB.COM/password/CreateMD5Password

Online hash/hash algorithm encryption tool:
http://tools.VeVB.COM/password/hash_encrypt

Online MD5/hash/SHA-1/SHA-2/SHA-256/SHA-512/SHA-3/RIPEMD-160 encryption tool:
http://tools.VeVB.COM/password/hash_md5_sha

Online sha1/sha224/sha256/sha384/sha512 encryption tool:
http://tools.VeVB.COM/password/sha_encode

For more information about Java related content, please check out the topics of this site: "Summary of Java Mathematical Operation Skills", "Tutorial on Java Data Structures and Algorithms", "Summary of Java Characters and String Operation Skills", "Summary of Java Operation DOM Node Skills" and "Summary of Java Cache Operation Skills"

I hope this article will be helpful to everyone's Java programming.