关于RSA加密算法的工具类
最近在捣鼓SSO(单点登录),就是一个在应用(系统)登录之后,当切换其他应用(系统)的时候,可以省去登录,提高用户的使用的便捷。(具体有时间在写)
期间涉及的安全问题,发送数据涉及账户密码以及分布系统之间的信息安全问题。
- package test.rsa;
- import java.io.*;
- import java.math.BigInteger;
- import java.security.*;
- import java.security.interfaces.*;
- import java.security.spec.*;
- import javax.crypto.*;
- import org.bouncycastle.util.encoders.Hex;
- import sun.misc.*;
- public class TestRSA {
- /**
- * * 生成密钥对 *
- *
- * @return KeyPair *
- * @throws EncryptException
- */
- public static KeyPair generateKeyPair() throws Exception {
- try {
- KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA",
- new org.bouncycastle.jce.provider.BouncyCastleProvider());
- final int KEY_SIZE = 1024;// 块加密的大小,是不要太大,否则效率会低
- keyPairGen.initialize(KEY_SIZE, new SecureRandom());
- KeyPair keyPair = keyPairGen.generateKeyPair();
- saveKeyPair(keyPair);
- return keyPair;
- } catch (Exception e) {
- throw new Exception(e.getMessage());
- }
- }
- public static KeyPair getKeyPair() throws Exception {
- FileInputStream fis = new FileInputStream(
- "D:/javasoft/TempTest/RSAKey.txt");
- ObjectInputStream oos = new ObjectInputStream(fis);
- KeyPair kp = (KeyPair) oos.readObject();
- oos.close();
- fis.close();
- return kp;
- }
- public static void saveKeyPair(KeyPair kp) throws Exception {
- FileOutputStream fos = new FileOutputStream(
- "D:/javasoft/TempTest/RSAKey.txt");
- ObjectOutputStream oos = new ObjectOutputStream(fos);
- // 生成密钥
- oos.writeObject(kp);
- oos.close();
- fos.close();
- }
- /**
- * * 生成公钥 *
- *
- * @param modulus *
- * @param publicExponent *
- * @return RSAPublicKey *
- * @throws Exception
- */
- public static RSAPublicKey generateRSAPublicKey(byte[] modulus,
- byte[] publicExponent) throws Exception {
- KeyFactory keyFac = null;
- try {
- keyFac = KeyFactory.getInstance("RSA",
- new org.bouncycastle.jce.provider.BouncyCastleProvider());
- } catch (NoSuchAlgorithmException ex) {
- throw new Exception(ex.getMessage());
- }
- RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(new BigInteger(
- modulus), new BigInteger(publicExponent));
- try {
- return (RSAPublicKey) keyFac.generatePublic(pubKeySpec);
- } catch (InvalidKeySpecException ex) {
- throw new Exception(ex.getMessage());
- }
- }
- /**
- * * 生成私钥 *
- *
- * @param modulus *
- * @param privateExponent *
- * @return RSAPrivateKey *
- * @throws Exception
- */
- public static RSAPrivateKey generateRSAPrivateKey(byte[] modulus,
- byte[] privateExponent) throws Exception {
- KeyFactory keyFac = null;
- try {
- keyFac = KeyFactory.getInstance("RSA",
- new org.bouncycastle.jce.provider.BouncyCastleProvider());
- } catch (NoSuchAlgorithmException ex) {
- throw new Exception(ex.getMessage());
- }
- RSAPrivateKeySpec priKeySpec = new RSAPrivateKeySpec(new BigInteger(
- modulus), new BigInteger(privateExponent));
- try {
- return (RSAPrivateKey) keyFac.generatePrivate(priKeySpec);
- } catch (InvalidKeySpecException ex) {
- throw new Exception(ex.getMessage());
- }
- }
- /**
- * 加密的方法
- * @throws IOException
- * @throws NoSuchPaddingException
- * @throws NoSuchAlgorithmException
- */
- private static String encrypt(PublicKey pk,String source) throws Exception{
- Cipher cipher = Cipher.getInstance("RSA",new org.bouncycastle.jce.provider.BouncyCastleProvider());
- cipher.init(Cipher.ENCRYPT_MODE, pk);
- byte[] sbt = source.getBytes();
- byte[] epByte = cipher.doFinal(sbt);
- BASE64Encoder encoder = new BASE64Encoder();
- String epStr = encoder.encode(epByte);
- return epStr;
- }
- private static String encrypt1(PublicKey pk,String source) throws Exception{
- Cipher cipher = Cipher.getInstance("RSA",new org.bouncycastle.jce.provider.BouncyCastleProvider());
- cipher.init(Cipher.ENCRYPT_MODE, pk);
- byte[] s = source.getBytes();
- byte[] en_s = cipher.doFinal(s);
- return new String(Hex.encode(en_s));
- }
- /**
- * 解密的方法
- * @throws Exception
- */
- public static String decrypt(PrivateKey pk,String source) throws Exception {
- /** 得到Cipher对象对已用公钥加密的数据进行RSA解密 */
- Cipher cipher = Cipher.getInstance("RSA",new org.bouncycastle.jce.provider.BouncyCastleProvider());
- cipher.init(Cipher.DECRYPT_MODE, pk);
- BASE64Decoder decoder = new BASE64Decoder();
- byte[] b1 = decoder.decodeBuffer(source);
- /** 执行解密操作 */
- byte[] b = cipher.doFinal(b1);
- return new String(b);
- }
- public static String decrypt1(PrivateKey pk,String source) throws Exception {
- /** 得到Cipher对象对已用公钥加密的数据进行RSA解密 */
- Cipher cipher = Cipher.getInstance("RSA",new org.bouncycastle.jce.provider.BouncyCastleProvider());
- cipher.init(Cipher.DECRYPT_MODE, pk);
- /** 执行解密操作 */
- byte[] b = cipher.doFinal(Hex.decode(source));
- return new String(b);
- }
- public static void main(String[] args) throws Exception {
- String s = "1-Test-我";
- String en_s = encrypt1(getKeyPair().getPublic(), s);
- System.out.println("----------------分割线--------------------------");
- System.out.println("加密之后:");
- System.out.println(en_s);
- System.out.println("----------------分割线--------------------------");
- String de_s = decrypt1(getKeyPair().getPrivate(),en_s);
- System.out.println("还原密文:");
- System.out.println(de_s);
- }
- }