package com.modules.Encryptor;  
  
import java.io.BufferedReader;  
import java.io.FileReader;  
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 java.util.ArrayList;  
import java.util.List;  
  
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 RSAEncryptor {  
  
      
    public static void main(String[] args){    
          
        String privateKeyPath = "/Users/Isaacs/Desktop/RSA_KEYS/rsa_public_key.pem";        // replace your public key path here  
        String publicKeyPath =  "/Users/Isaacs/Desktop/RSA_KEYS/pkcs8_private_key.pem";     // replace your private path here  
        RSAEncryptor rsaEncryptor = new RSAEncryptor(privateKeyPath, publicKeyPath);  
  
        try {  
              
            String test = "JAVA";  
            String testRSAEnWith64 = rsaEncryptor.encryptWithBase64(test);  
            String testRSADeWith64 = rsaEncryptor.decryptWithBase64(testRSAEnWith64);  
            System.out.println("\nEncrypt: \n" + testRSAEnWith64);  
            System.out.println("\nDecrypt: \n" + testRSADeWith64);  
              
            // NSLog the encrypt string from Xcode , and paste it here.  
            // 請貼上來自IOS端加密後的字串  
//            String rsaBase46StringFromIOS =  
//                    "nIIV7fVsHe8QquUbciMYbbumoMtbBuLsCr2yMB/WAhm+S/kGRPlf+k2GH8imZIYQ" + "\r" +  
//                    "QBDssVLQmS392QlxS87hnwMRJIzWw6vdRv/k79TgTfu6tI/9QTqIOvNlQIqtIcVm" + "\r" +  
//                    "R/suvydoymKgdlB+ce5/tHSxfqEOLLrL1Zl2PqJSP4A=";  
//              
//            String decryptStringFromIOS = rsaEncryptor.decryptWithBase64(rsaBase46StringFromIOS);  
//            System.out.println("Decrypt result from ios client: \n" + decryptStringFromIOS);  
              
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
  
    }  
  
  
  
  
  
    /** 
     * @param publicKeyFilePath      
     * @param privateKeyFilePath     
     */  
    public RSAEncryptor(String publicKeyFilePath, String privateKeyFilePath) throws Exception {  
        String public_key = getKeyFromFile(publicKeyFilePath);  
        String private_key = getKeyFromFile(privateKeyFilePath);  
        loadPublicKey(public_key);    
        loadPrivateKey(private_key);    
    }  
    public RSAEncryptor() {  
        // load the PublicKey and PrivateKey manually  
    }  
      
      
    public String getKeyFromFile(String filePath) throws Exception {  
        BufferedReader bufferedReader = new BufferedReader(new FileReader(filePath));  
          
        String line = null;  
        List<String> list = new ArrayList<String>();  
        while ((line = bufferedReader.readLine()) != null){  
            list.add(line);  
        }  
          
        // remove the firt line and last line  
        StringBuilder stringBuilder = new StringBuilder();  
        for (int i = 1; i < list.size() - 1; i++) {  
            stringBuilder.append(list.get(i)).append("\r");  
        }  
          
        String key = stringBuilder.toString();  
        return key;  
    }  
      
    public String decryptWithBase64(String base64String) throws Exception {  
        //  http://commons.apache.org/proper/commons-codec/ : org.apache.commons.codec.binary.Base64  
        // sun.misc.BASE64Decoder  
        byte[] binaryData = decrypt(getPrivateKey(), new BASE64Decoder().decodeBuffer(base64String) /*org.apache.commons.codec.binary.Base64.decodeBase64(base46String.getBytes())*/);  
        String string = new String(binaryData);  
        return string;  
    }  
      
    public String encryptWithBase64(String string) throws Exception {  
        //  http://commons.apache.org/proper/commons-codec/ : org.apache.commons.codec.binary.Base64  
        // sun.misc.BASE64Encoder  
        byte[] binaryData = encrypt(getPublicKey(), string.getBytes());  
        String base64String = new BASE64Encoder().encodeBuffer(binaryData) /* org.apache.commons.codec.binary.Base64.encodeBase64(binaryData) */;  
        return base64String;  
    }  
    
      
      
    // convenient properties  
    public static RSAEncryptor sharedInstance = null;  
    public static void setSharedInstance (RSAEncryptor rsaEncryptor) {  
        sharedInstance = rsaEncryptor;  
    }  
      
      
      
      
    // From: http://blog.csdn.net/chaijunkun/article/details/7275632  
  
    /**  
     * 私鑰  
     */    
    private RSAPrivateKey privateKey;    
    
    /**  
     * 公鑰  
     */    
    private RSAPublicKey publicKey;    
        
    /**  
     * 獲取私鑰  
     * @return 當前的私鑰物件  
     */    
    public RSAPrivateKey getPrivateKey() {    
        return privateKey;    
    }    
    
    /**  
     * 獲取公鑰  
     * @return 當前的公鑰物件  
     */    
    public RSAPublicKey getPublicKey() {    
        return publicKey;    
    }    
    
    /**  
     * 隨機生成金鑰對  
     */    
    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();    
    }    
    
    /**  
     * 從檔案中輸入流中載入公鑰  
     * @param in 公鑰輸入流  
     * @throws Exception 載入公鑰時產生的異常  
     */    
    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("公鑰資料流讀取錯誤");    
        } catch (NullPointerException e) {    
            throw new Exception("公鑰輸入流為空");    
        }    
    }    
    
    /**  
     * 從字串中載入公鑰  
     * @param publicKeyStr 公鑰資料字串  
     * @throws Exception 載入公鑰時產生的異常  
     */    
    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("無此演算法");    
        } catch (InvalidKeySpecException e) {    
            throw new Exception("公鑰非法");    
        } catch (IOException e) {    
            throw new Exception("公鑰資料內容讀取錯誤");    
        } catch (NullPointerException e) {    
            throw new Exception("公鑰資料為空");    
        }    
    }    
    
    /**  
     * 從檔案中載入私鑰  
     * @param keyFileName 私鑰檔名  
     * @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("私鑰資料讀取錯誤");    
        } catch (NullPointerException e) {    
            throw new Exception("私鑰輸入流為空");    
        }    
    }    
    
    public void loadPrivateKey(String privateKeyStr) throws Exception{    
        try {    
            BASE64Decoder base64Decoder= new BASE64Decoder();    
            byte[] buffer= base64Decoder.decodeBuffer(privateKeyStr);    
            PKCS8EncodedKeySpec keySpec= new PKCS8EncodedKeySpec(buffer);    
            KeyFactory keyFactory= KeyFactory.getInstance("RSA");    
            this.privateKey= (RSAPrivateKey) keyFactory.generatePrivate(keySpec);    
        } catch (NoSuchAlgorithmException e) {    
            throw new Exception("無此演算法");    
        } catch (InvalidKeySpecException e) {    
            e.printStackTrace();  
            throw new Exception("私鑰非法");    
        } catch (IOException e) {    
            throw new Exception("私鑰資料內容讀取錯誤");    
        } catch (NullPointerException e) {    
            throw new Exception("私鑰資料為空");    
        }    
    }    
    
    /**  
     * 加密過程  
     * @param publicKey 公鑰  
     * @param plainTextData 明文資料  
     * @return  
     * @throws Exception 加密過程中的異常資訊  
     */    
    public byte[] encrypt(RSAPublicKey publicKey, byte[] plainTextData) throws Exception{    
        if(publicKey== null){    
            throw new Exception("加密公鑰為空, 請設定");    
        }    
        Cipher cipher= null;    
        try {    
            cipher= Cipher.getInstance("RSA");//, new BouncyCastleProvider());    
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);    
            byte[] output= cipher.doFinal(plainTextData);    
            return output;    
        } catch (NoSuchAlgorithmException e) {    
            throw new Exception("無此加密演算法");    
        } catch (NoSuchPaddingException e) {    
            e.printStackTrace();    
            return null;    
        }catch (InvalidKeyException e) {    
            throw new Exception("加密公鑰非法,請檢查");    
        } catch (IllegalBlockSizeException e) {    
            throw new Exception("明文長度非法");    
        } catch (BadPaddingException e) {    
            throw new Exception("明文資料已損壞");    
        }    
    }    
    
    /**  
     * 解密過程  
     * @param privateKey 私鑰  
     * @param cipherData 密文資料  
     * @return 明文  
     * @throws Exception 解密過程中的異常資訊  
     */    
    public byte[] decrypt(RSAPrivateKey privateKey, byte[] cipherData) throws Exception{    
        if (privateKey== null){    
            throw new Exception("解密私鑰為空, 請設定");    
        }    
        Cipher cipher= null;    
        try {    
            cipher= Cipher.getInstance("RSA");//, new BouncyCastleProvider());    
            cipher.init(Cipher.DECRYPT_MODE, privateKey);    
            byte[] output= cipher.doFinal(cipherData);    
            return output;    
        } catch (NoSuchAlgorithmException e) {    
            throw new Exception("無此解密演算法");    
        } catch (NoSuchPaddingException e) {    
            e.printStackTrace();    
            return null;    
        }catch (InvalidKeyException e) {    
            throw new Exception("解密私鑰非法,請檢查");    
        } catch (IllegalBlockSizeException e) {    
            throw new Exception("密文長度非法");    
        } catch (BadPaddingException e) {    
            throw new Exception("密文資料已損壞");    
        }           
    }    
    
      
      
    /**  
     * 位元組資料轉字串專用集合  
     */    
    private static final char[] HEX_CHAR= {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};   
      
    /**  
     * 位元組資料轉十六進位制字串  
     * @param data 輸入資料  
     * @return 十六進位制內容  
     */    
    public static String byteArrayToString(byte[] data){    
        StringBuilder stringBuilder= new StringBuilder();    
        for (int i=0; i<data.length; i++){    
            //取出位元組的高四位 作為索引得到相應的十六進位制識別符號 注意無符號右移    
            stringBuilder.append(HEX_CHAR[(data[i] & 0xf0)>>> 4]);    
            //取出位元組的低四位 作為索引得到相應的十六進位制識別符號    
            stringBuilder.append(HEX_CHAR[(data[i] & 0x0f)]);    
            if (i<data.length-1){    
                stringBuilder.append(' ');    
            }    
        }    
        return stringBuilder.toString();    
    }    
  
  
｝