RSA使用js加密，使用java解密

http://yajiao.iteye.com/blog/1772835

RSA算法使用javascript加密，使用java解密，提供完整代码及例子下载。
    javascript加密介绍参见另一篇：javascript使用RSA加密提交数据。本篇的例子使用的js是上一篇中提到的第2个版本。
   
    本篇是服务端解密部分，并且提供可运行的包括js的全部示例代码。
    由于sun虚拟机自带的RSA解密填充模式使用的都是特殊的PADDING模式，而js中使用的padding其实就是特殊处理的部分，实际加密时是nopadding模式，所以无法直接使用sun自带的RSA算法在服务器端解密，可以使用第3方bouncycastle提供的算法程序，最新版可以在这里下载http://www.bouncycastle.org/latest_releases.html
   
  
Java代码 
import java.security.KeyFactory; 
import java.security.KeyPair; 
import java.security.KeyPairGenerator; 
import java.security.PrivateKey; 
import java.security.Provider; 
import java.security.PublicKey; 
import java.security.SecureRandom; 
import java.security.spec.PKCS8EncodedKeySpec; 
import java.security.spec.X509EncodedKeySpec; 
 
import javax.crypto.Cipher; 
 
import org.bouncycastle.jce.provider.BouncyCastleProvider; 
import org.bouncycastle.util.encoders.Base64; 
import org.bouncycastle.util.encoders.Hex; 
 
public class RSABCExample { 
 
    // 可以先注册到虚拟机中,再通过名称使用;也可以不注册,直接传入后使用 
    public static final Provider pro = new BouncyCastleProvider(); 
     
    private static final String charSet = "UTF-8"; 
 
    private static String publicKeyStr = null; 
    private static String privateKeyStr = null; 
    private static PrivateKey privateKey = null; 
    private static PublicKey publicKey = null; 
    // 种子,改变后,生成的密钥对会发生变化 
    private static final String seedKey = "random"; 
 
    public static void generateKeyPair() throws Exception { 
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA", pro); 
        kpg.initialize(1024, new SecureRandom(seedKey.getBytes())); 
        KeyPair kp = kpg.generateKeyPair(); 
 
        privateKey = kp.getPrivate(); 
        privateKeyStr = new String(Base64.encode(privateKey.getEncoded())); 
        publicKey = kp.getPublic(); 
        publicKeyStr = new String(Base64.encode(publicKey.getEncoded())); 
 
        System.out.println("PrivateKey:" + privateKey); 
        System.out.println("PublicKey:" + publicKey); 
 
        System.out.println(privateKeyStr); 
        System.out.println(publicKeyStr); 
    } 
 
    public static PublicKey getPublicRSAKey(String key) throws Exception { 
        X509EncodedKeySpec x509 = new X509EncodedKeySpec(Base64.decode(key)); 
        KeyFactory kf = KeyFactory.getInstance("RSA", pro); 
        return kf.generatePublic(x509); 
    } 
 
    public static PrivateKey getPrivateRSAKey(String key) throws Exception { 
        PKCS8EncodedKeySpec pkgs8 = new PKCS8EncodedKeySpec(Base64.decode(key)); 
        KeyFactory kf = KeyFactory.getInstance("RSA", pro); 
        return kf.generatePrivate(pkgs8); 
    } 
 
    public static byte[] encrypt(String input) throws Exception { 
        long start = System.currentTimeMillis(); 
        Cipher cipher = Cipher.getInstance("RSA", pro); 
        cipher.init(Cipher.ENCRYPT_MODE, publicKey); 
        byte[] re = cipher.doFinal(input.getBytes(charSet)); 
        long end = System.currentTimeMillis(); 
//      System.out.println("encrypt use time "+(end-start)+""); 
        return re; 
    } 
 
    public static byte[] decrypt(byte[] encrypted) throws Exception { 
        long start = System.currentTimeMillis(); 
        Cipher cipher = Cipher.getInstance("RSA", pro); 
        cipher.init(Cipher.DECRYPT_MODE, privateKey); 
        byte[] re = cipher.doFinal(encrypted); 
        long end = System.currentTimeMillis(); 
//      System.out.println("decrypt use time "+(end-start)+""); 
        return re; 
    } 
     
    public static String decodeJsValue(String jsValue) throws Exception { 
        byte[] input = Hex.decode(jsValue); 
        byte[] raw = decrypt(input); 
         
        // 标志位为0之后的是输入的有效字节 
        int i = raw.length - 1; 
        while (i > 0 && raw[i] != 0) { 
            i--; 
        } 
        i++; 
        byte[] data = new byte[raw.length - i]; 
        for (int j = i; j < raw.length; j++) { 
            data[j - i] = raw[j]; 
        } 
         
        return new String(data,charSet); 
    } 
 
    public static void main(String[] args) throws Exception { 
        generateKeyPair(); 
        PublicKey pb = getPublicRSAKey(publicKeyStr); 
        System.out.println(pb.equals(publicKey)); 
        PrivateKey ppk = getPrivateRSAKey(privateKeyStr); 
        System.out.println(ppk.equals(privateKey)); 
 
        String input = "测试abcABC123"; 
        byte[] en = encrypt(input); 
        System.out.println(new String(Hex.encode(en))); 
 
        byte[] re = decrypt(en); 
        System.out.println(new String(re, charSet)); 
         
        // js加密后的值 
        String de = "08f7e292ccb4c73a981569a9c2dbf2b9c0c2cf615967282863e6e358432af288f1f026ed91a8ff5f6579ac246af9ce1f94f85e92b8a926627b95e6bd05b00b80a5548e9ce1a9bb2a20073cce629936ab9e27021af7370c2664065107a702c1805a4ec131a3573007213da3e390221053867074a427ffc28aa642fe2099ad7332"; 
        System.out.println(decodeJsValue(de)); 
         
        re = decrypt(en); 
        System.out.println(new String(re, charSet)); 
    } 
 
}