参考博客：https://www.cnblogs.com/taoshihan/p/6340854.html
一、确认Linux服务器是否安装openssl
确认指令：openssl version -a
如果没有安装，可以百度参考
二、生成RSA公私钥
1、进入Linux系统，随意一个文件夹
demo：cd /home/RSA
package com.snowball.common.util.test; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.FileInputStream; import java.security.InvalidKeyException; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; import java.security.interfaces.RSAPrivateKey; import java.security.interfaces.RSAPublicKey; import java.security.spec.InvalidKeySpecException; import java.security.spec.X509EncodedKeySpec; import java.security.spec.RSAPrivateKeySpec; import org.bouncycastle.asn1.ASN1Sequence; import org.bouncycastle.asn1.pkcs.RSAPrivateKeyStructure; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import org.bouncycastle.jce.provider.BouncyCastleProvider; import sun.misc.BASE64Decoder; import sun.misc.BASE64Encoder; @SuppressWarnings("restriction") public class RSAUtil { /** * 私钥 */ private RSAPrivateKey privateKey; /** * 公钥 */ private RSAPublicKey publicKey; /** * 获取私钥 * @return 当前的私钥对象 */ public RSAPrivateKey getPrivateKey() { return privateKey; } /** * 获取公钥 * @return 当前的公钥对象 */ public RSAPublicKey getPublicKey() { return publicKey; } /** * 随机生成密钥对 */ public void genKeyPair(){ KeyPairGenerator keyPairGen= null; try { keyPairGen= KeyPairGenerator.getInstance("RSA"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } keyPairGen.initialize(1024, new SecureRandom()); KeyPair keyPair= keyPairGen.generateKeyPair(); this.privateKey= (RSAPrivateKey) keyPair.getPrivate(); this.publicKey= (RSAPublicKey) keyPair.getPublic(); } /** * 从文件中输入流中加载公钥 * @param in 公钥输入流 * @throws Exception 加载公钥时产生的异常 */ public void loadPublicKey(InputStream in) throws Exception{ try { BufferedReader br= new BufferedReader(new InputStreamReader(in)); String readLine= null; StringBuilder sb= new StringBuilder(); while((readLine= br.readLine())!=null){ if(readLine.charAt(0)=='-'){ continue; }else{ sb.append(readLine); sb.append('\r'); } } loadPublicKey(sb.toString()); } catch (IOException e) { throw new Exception("公钥数据流读取错误"); } catch (NullPointerException e) { throw new Exception("公钥输入流为空"); } } /** * 从字符串中加载公钥 * @param publicKeyStr 公钥数据字符串 * @throws Exception 加载公钥时产生的异常 */ public void loadPublicKey(String publicKeyStr) throws Exception{ try { BASE64Decoder base64Decoder= new BASE64Decoder(); byte[] buffer= base64Decoder.decodeBuffer(publicKeyStr); KeyFactory keyFactory= KeyFactory.getInstance("RSA"); X509EncodedKeySpec keySpec= new X509EncodedKeySpec(buffer); this.publicKey= (RSAPublicKey) keyFactory.generatePublic(keySpec); } catch (NoSuchAlgorithmException e) { throw new Exception("无此算法"); } catch (InvalidKeySpecException e) { throw new Exception("公钥非法"); } catch (IOException e) { throw new Exception("公钥数据内容读取错误"); } catch (NullPointerException e) { throw new Exception("公钥数据为空"); } } /** * 从文件中加载私钥 * @param keyFileName 私钥文件名 * @return 是否成功 * @throws Exception */ public void loadPrivateKey(InputStream in) throws Exception{ try { BufferedReader br= new BufferedReader(new InputStreamReader(in)); String readLine= null; StringBuilder sb= new StringBuilder(); while((readLine= br.readLine())!=null){ if(readLine.charAt(0)=='-'){ continue; }else{ sb.append(readLine); sb.append('\r'); } } loadPrivateKey(sb.toString()); } catch (IOException e) { throw new Exception("私钥数据读取错误"); } catch (NullPointerException e) { throw new Exception("私钥输入流为空"); } } public void loadPrivateKey(String privateKeyStr) throws Exception{ try { BASE64Decoder base64Decoder= new BASE64Decoder(); byte[] buffer= base64Decoder.decodeBuffer(privateKeyStr); RSAPrivateKeyStructure asn1PrivKey = new RSAPrivateKeyStructure((ASN1Sequence) ASN1Sequence.fromByteArray(buffer)); RSAPrivateKeySpec rsaPrivKeySpec = new RSAPrivateKeySpec(asn1PrivKey.getModulus(), asn1PrivKey.getPrivateExponent()); KeyFactory keyFactory= KeyFactory.getInstance("RSA"); RSAPrivateKey priKey=(RSAPrivateKey) keyFactory.generatePrivate(rsaPrivKeySpec); this.privateKey=priKey; } catch (NoSuchAlgorithmException e) { throw new Exception("无此算法"); } catch (InvalidKeySpecException e) { throw new Exception("私钥非法"); } catch (IOException e) { throw new Exception("私钥数据内容读取错误"); } catch (NullPointerException e) { throw new Exception("私钥数据为空"); } } /** * 加密过程 * @param publicKey 公钥 * @param plainTextData 明文数据 * @return * @throws Exception 加密过程中的异常信息 */ public byte[] encrypt(RSAPublicKey publicKey, byte[] plainTextData) throws Exception{ if(publicKey== null){ throw new Exception("加密公钥为空, 请设置"); } Cipher cipher= null; try { cipher= Cipher.getInstance("RSA/ECB/PKCS1Padding", new BouncyCastleProvider()); cipher.init(Cipher.ENCRYPT_MODE, publicKey); byte[] output= cipher.doFinal(plainTextData); return output; } catch (NoSuchAlgorithmException e) { throw new Exception("无此加密算法"); } catch (NoSuchPaddingException e) { e.printStackTrace(); return null; }catch (InvalidKeyException e) { throw new Exception("加密公钥非法,请检查"); } catch (IllegalBlockSizeException e) { throw new Exception("明文长度非法"); } catch (BadPaddingException e) { throw new Exception("明文数据已损坏"); } } /** * 解密过程 * @param privateKey 私钥 * @param cipherData 密文数据 * @return 明文 * @throws Exception 解密过程中的异常信息 */ public byte[] decrypt(RSAPrivateKey privateKey, byte[] cipherData) throws Exception{ if (privateKey== null){ throw new Exception("解密私钥为空, 请设置"); } Cipher cipher= null; try { cipher= Cipher.getInstance("RSA/ECB/PKCS1Padding", new BouncyCastleProvider()); cipher.init(Cipher.DECRYPT_MODE, privateKey); byte[] output= cipher.doFinal(cipherData); return output; } catch (NoSuchAlgorithmException e) { throw new Exception("无此解密算法"); } catch (NoSuchPaddingException e) { e.printStackTrace(); return null; }catch (InvalidKeyException e) { throw new Exception("解密私钥非法,请检查"); } catch (IllegalBlockSizeException e) { throw new Exception("密文长度非法"); } catch (BadPaddingException e) { throw new Exception("密文数据已损坏"); } } public static void main(String[] args){ RSAUtil rsaEncrypt= new RSAUtil(); //加载公钥 try { rsaEncrypt.loadPublicKey(new FileInputStream(RSAUtil.class.getClassLoader().getResource("rsa_public_key.pem").getPath())); System.out.println("加载公钥成功"); } catch (Exception e) { System.err.println(e.getMessage()); System.err.println("加载公钥失败"); } //加载私钥 try { rsaEncrypt.loadPrivateKey(new FileInputStream(RSAUtil.class.getClassLoader().getResource("rsa_private_key.pem").getPath())); System.out.println("加载私钥成功"); } catch (Exception e) { System.err.println(e.getMessage()); System.err.println("加载私钥失败"); } //完整加解密 try { //测试字符串 String encryptStr= "13392801646"; System.out.println("加密前:"); System.out.println(encryptStr); //加密 byte[] cipher = rsaEncrypt.encrypt(rsaEncrypt.getPublicKey(), encryptStr.getBytes()); //解密 byte[] plainText = rsaEncrypt.decrypt(rsaEncrypt.getPrivateKey(), cipher); BASE64Encoder encode = new BASE64Encoder(); String buffer= encode.encode(cipher); System.out.println("加密后:"); System.out.println(new String(buffer)); System.out.println("解密后:"); System.out.println(new String(plainText)); } catch (Exception e) { System.err.println(e.getMessage()); } //小米提供的密文，解密用例 try { BASE64Decoder base64Decoder= new BASE64Decoder(); byte[] dd = base64Decoder.decodeBuffer("tv8BHq/CYcEC/eJo68hE+r2lYwzx/bfaNfrZx+a81oSLjHBWl+6lgy+1DuBD7pThA9cFrpcHimkV7iHZVp8AWvJyI5U2Z7jDhG4XK1/P0kZK4wShI6ay7MyFYOI4fYL47RpCongRcYsv2A1RDW92/0lsiut43BXD8K80xA56sBQ="); byte[] dds = rsaEncrypt.decrypt(rsaEncrypt.getPrivateKey(), dd); System.out.println("测试解密："+new String(dds)); } catch (Exception e) { } } }
2、生成RSA私钥
命令：openssl genrsa -out 私钥名称.pem 1024
demo：openssl genrsa -out rsa_private_key.pem 1024
3、生成私钥
命令：openssl rsa -in 私钥名称.pem -pubout -out 公钥名称.pem
demo：openssl rsa -in rsa_private_key.pem -pubout -out rsa_public_key.pem
4、通过ftp工具下载生成的公私钥
5、导入项目，代码实现参考"RSAUtil.java"文件