很简单的一个需求,ipad端给密码RSA加密,传到java后台,解密。RSA加密算法是基于一个密钥对的,分为公钥和私钥,一般情况公钥加密,私钥解密,但也可私钥加密,公钥解密。还可以验签,就是先用私钥对数据进行加密,然后对加密后的数据进行签名,得到一个签名值。然后再用公钥先验签,证明是对应私钥加密过的数据才解密。主要是为了防止来源不确定的数据。
根据上面的介绍,大家也都知道,RSA算法的关键就是密钥对,我和IOS的同事各自找了RSA的算法实现代码,都能正常根据密钥对加解密。问题是我们各自使用对方的密钥对就不能加解密成功。IOS同事也是一个新手。连RSA算法是个什么概念都没搞清楚,我也懂点IOS。所以就陪着他一起看代码,找资料。看到底什么原因引起的密钥对不能共用。后来找到下面这篇文章:
Java中使用OpenSSL生成的RSA公私钥进行数据加解密
原来在用mac 系统中自带的openssl生成的密钥对文件是X509编码格式的。而我们JAVA所需的私钥文件是PKCS#8编码格式的。。所以要将在mac 系统中生成的私钥文件转下码就行了。转码方式参考上面链接。附下java代码:
- import java.io.BufferedReader;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- 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.PKCS8EncodedKeySpec;
- import java.security.spec.X509EncodedKeySpec;
- import javax.crypto.BadPaddingException;
- import javax.crypto.Cipher;
- import javax.crypto.IllegalBlockSizeException;
- import javax.crypto.NoSuchPaddingException;
- import sun.misc.BASE64Decoder;
- import sun.misc.BASE64Encoder;
- public class RSAEncrypt {
- private static final String DEFAULT_PUBLIC_KEY=
- "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQChDzcjw/rWgFwnxunbKp7/4e8w" + "\r" +
- "/UmXx2jk6qEEn69t6N2R1i/LmcyDT1xr/T2AHGOiXNQ5V8W4iCaaeNawi7aJaRht" + "\r" +
- "Vx1uOH/2U378fscEESEG8XDqll0GCfB1/TjKI2aitVSzXOtRs8kYgGU78f7VmDNg" + "\r" +
- "XIlk3gdhnzh+uoEQywIDAQAB" + "\r";
- private static final String DEFAULT_PRIVATE_KEY=
- "MIICdQIBADANBgkqhkiG9w0BAQEFAASCAl8wggJbAgEAAoGBAKEPNyPD+taAXCfG" + "\r" +
- "6dsqnv/h7zD9SZfHaOTqoQSfr23o3ZHWL8uZzINPXGv9PYAcY6Jc1DlXxbiIJpp4" + "\r" +
- "1rCLtolpGG1XHW44f/ZTfvx+xwQRIQbxcOqWXQYJ8HX9OMojZqK1VLNc61GzyRiA" + "\r" +
- "ZTvx/tWYM2BciWTeB2GfOH66gRDLAgMBAAECgYBp4qTvoJKynuT3SbDJY/XwaEtm" + "\r" +
- "u768SF9P0GlXrtwYuDWjAVue0VhBI9WxMWZTaVafkcP8hxX4QZqPh84td0zjcq3j" + "\r" +
- "DLOegAFJkIorGzq5FyK7ydBoU1TLjFV459c8dTZMTu+LgsOTD11/V/Jr4NJxIudo" + "\r" +
- "MBQ3c4cHmOoYv4uzkQJBANR+7Fc3e6oZgqTOesqPSPqljbsdF9E4x4eDFuOecCkJ" + "\r" +
- "DvVLOOoAzvtHfAiUp+H3fk4hXRpALiNBEHiIdhIuX2UCQQDCCHiPHFd4gC58yyCM" + "\r" +
- "6Leqkmoa+6YpfRb3oxykLBXcWx7DtbX+ayKy5OQmnkEG+MW8XB8wAdiUl0/tb6cQ" + "\r" +
- "FaRvAkBhvP94Hk0DMDinFVHlWYJ3xy4pongSA8vCyMj+aSGtvjzjFnZXK4gIjBjA" + "\r" +
- "2Z9ekDfIOBBawqp2DLdGuX2VXz8BAkByMuIh+KBSv76cnEDwLhfLQJlKgEnvqTvX" + "\r" +
- "TB0TUw8avlaBAXW34/5sI+NUB1hmbgyTK/T/IFcEPXpBWLGO+e3pAkAGWLpnH0Zh" + "\r" +
- "Fae7oAqkMAd3xCNY6ec180tAe57hZ6kS+SYLKwb4gGzYaCxc22vMtYksXHtUeamo" + "\r" +
- "1NMLzI2ZfUoX" + "\r";
- /**
- * 私钥
- */
- private RSAPrivateKey privateKey;
- /**
- * 公钥
- */
- private RSAPublicKey publicKey;
- /**
- * 字节数据转字符串专用集合
- */
- private static final char[] HEX_CHAR= {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
- /**
- * 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){