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C# encrypt to Java Decrypt

I am using a C# "encrypt" and need a Java "decrypt" method. I need help in java that i can't replicate C# decryption on java and it is not explicit Padding on C# , i don't know what use in java and my key size I think is different but I am not sure. I'm very confused.
know that i need change Java Policy , and did it ! and Change Key size JAVA to 32 bytes.
C#
using System;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using Voa.Cross.Util.Extensions;
namespace Voa.Core.Safeties
{
public class Security
{
private readonly string _defaultKey = "sjkdhfjksdhf3444KDFK4nFLFGKdsnjcnj2cmkeKDIK484dmd999sksksksUUddUZ83k030394m49jdjPuWzRk8Zq2PfnpR3YrYWSq2AaUT6meeC3tr36nTVkuudKWbDyPjhUwbwXBzkUhSPKPpSRheR49em4qJWa6YHSCjKX3K93FEMnqXhYauXwjJwbHXfPWTSdxy6ebCBPyAfqk7Uz5nrRddVjZrxWNCMZYG3PbcvPWA34ekdkd454ldnvJKl";
private readonly int _divisionKey = 4;
private readonly byte[] _iv = new byte[16] {0x26, 0xdc, 0xff, 0x00, 0xad, 0xed, 0x7a, 0xee, 0xc5, 0xfe, 0x07, 0xaf, 0x4d, 0x08, 0x22, 0x3c};
private byte[] _key;
public Security() => _key = SHA256.Create().ComputeHash(Encoding.ASCII.GetBytes(_defaultKey));
public string Encrypt(string data, string key)
{
if (!string.IsNullOrEmpty(key))
{
CustomKey(key);
}
var encryptor = Aes.Create();
encryptor.Mode = CipherMode.CBC;
// Set key and IV
var aesKey = new byte[32];
Array.Copy(_key, 0, aesKey, 0, 32);
encryptor.Key = aesKey;
encryptor.IV = _iv;
var memoryStream = new MemoryStream();
var aesEncryptor = encryptor.CreateEncryptor();
var cryptoStream = new CryptoStream(memoryStream, aesEncryptor, CryptoStreamMode.Write);
var plainBytes = Encoding.ASCII.GetBytes(data);
cryptoStream.Write(plainBytes, 0, plainBytes.Length);
cryptoStream.FlushFinalBlock();
var cipherBytes = memoryStream.ToArray();
memoryStream.Close();
cryptoStream.Close();
var cipherText = Convert.ToBase64String(cipherBytes, 0, cipherBytes.Length);
return cipherText;
}
public string Decrypt(string data, string key)
{
if (!string.IsNullOrEmpty(key))
{
CustomKey(key);
}
var encryptor = Aes.Create();
encryptor.Mode = CipherMode.CBC;
var aesKey = new byte[32];
Array.Copy(_key, 0, aesKey, 0, 32);
encryptor.Key = aesKey;
encryptor.IV = _iv;
var memoryStream = new MemoryStream();
var aesDecryptor = encryptor.CreateDecryptor();
var cryptoStream = new CryptoStream(memoryStream, aesDecryptor, CryptoStreamMode.Write);
var plainText = string.Empty;
try
{
var cipherBytes = Convert.FromBase64String(data);
cryptoStream.Write(cipherBytes, 0, cipherBytes.Length);
cryptoStream.FlushFinalBlock();
var plainBytes = memoryStream.ToArray();
plainText = Encoding.ASCII.GetString(plainBytes, 0, plainBytes.Length);
}
finally
{
memoryStream.Close();
cryptoStream.Close();
}
return plainText;
}
private void CustomKey(string key)
{
var blockSize = key.Length / _divisionKey;
var splitKey = key.CutString(blockSize).ToList();
var splitDefaultKey = _defaultKey.CutString(blockSize).ToList();
var newKey = string.Concat(splitDefaultKey.Intertwine(splitKey).ToList());
_key = SHA256.Create().ComputeHash(Encoding.ASCII.GetBytes(newKey));
}
}
}
JAVA test...
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class SecurityAESEncryption {
private static final String _key = "sjkdhfjksdhf3444KDFK4nFLFGKdsnjcnj2cmkeKDIK484dmd999sksksksUUddUZ83k030394m49jdjPuWzRk8Zq2PfnpR3YrYWSq2AaUT6meeC3tr36nTVkuudKWbDyPjhUwbwXBzkUhSPKPpSRheR49em4qJWa6YHSCjKX3K93FEMnqXhYauXwjJwbHXfPWTSdxy6ebCBPyAfqk7Uz5nrRddVjZrxWNCMZYG3PbcvPWA34ekdkd454ldnvJKl";
private static final char[] initCharArray = new char[] {0x26, 0xdc, 0xff, 0x00, 0xad, 0xed, 0x7a, 0xee, 0xc5, 0xfe, 0x07, 0xaf, 0x4d, 0x08, 0x22, 0x3c};
private static final byte[] initVector = SecurityAESEncryption.charToByteArray(initCharArray);
//private static final String initArray = "26dcff00aded7aeec5fe07af4d08223c";
//private static final byte[] ivValue = SecurityAESEncryption.hexStringToByteArray(initArray);
//private static final byte[] key = DigestUtils.sha256(_key.getBytes(StandardCharsets.US_ASCII)).;
private static final byte[] key = SecurityAESEncryption.computeHash(_key);
public static String encrypt(String value) {
try {
System.out.println(key.length);
System.out.println(Base64.decodeBase64(key).length);
byte[] aesKey = new byte[32];
System.arraycopy(key, 0, aesKey, 0, 32);
SecretKeySpec skeySpec = new SecretKeySpec(aesKey, "AES");
IvParameterSpec iv = new IvParameterSpec(initVector);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
byte[] encrypted = cipher.doFinal(value.getBytes());
return Base64.encodeBase64String(encrypted);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static String decrypt(String encrypted) {
try {
byte[] encryptedBytes = Base64.decodeBase64(encrypted);
System.out.println(key.length);
System.out.println(Base64.decodeBase64(key).length);
byte[] aesKey = new byte[32];
System.arraycopy(key, 0, aesKey, 0, 32);
IvParameterSpec iv = new IvParameterSpec(initVector);
SecretKeySpec skeySpec = new SecretKeySpec(aesKey, "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);
//byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));
byte[] original = cipher.doFinal(encryptedBytes);
return new String(original,StandardCharsets.US_ASCII);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static byte[] charToByteArray(char[] x)
{
final byte[] res = new byte[x.length];
for (int i = 0; i < x.length; i++)
{
res[i] = (byte) x[i];
}
return res;
}
public static byte[] computeHash(String input) {
try {
// Static getInstance method is called with hashing SHA
MessageDigest md = MessageDigest.getInstance("SHA-256");
return md.digest(input.getBytes(StandardCharsets.US_ASCII));
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return null;
}
public static byte[] hexStringToByteArray(String s) {
int len = s.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
return data;
}
public static void main(String[] args) {
String originalString = "123456!##";
System.out.println("Original String to encrypt - " + originalString);
String encryptedString = encrypt(originalString);
System.out.println("Encrypted String - " + encryptedString);
String decryptedString = decrypt("Ci10C7ZjUPoEnitdh7QkEw==");
System.out.println("After decryption - " + decryptedString);
}

Your edited Java prog now successfully encrypts the string "123456!##" to this (Base64 encoded) string "LnZV0Vph+eUeJLT2Gst0kw==" using a String as input to a SHA-256 digest, so the real key used for en-/decryption is
(hex) "07c3491eaa6a6289ca91b7b0f290d60688538860b44753f1cf9617977985d2db".
Using this encoded string as input for your decrypt method returns the original string but when using the encoded/encrypted
string "Ci10C7ZjUPoEnitdh7QkEw==" I'm running into this exception:
javax.crypto.BadPaddingException: Given final block not properly padded.
Such issues can arise if a bad key is used during decryption.
Imho this indicates that the key your're using on Java-side is not the same as on C#-side (we don't see the real input
to Encrypt and I don't know what "CustomKey" is doing :-).
Could you please print out
the aeskey and -iv from your C#-Encrypt method directly after you setup them in encryptor-inits and share them here,
that might be usefull for us to help.
public string Encrypt(string data, string key)
...
// Set key and IV
var aesKey = new byte[32];
Array.Copy(_key, 0, aesKey, 0, 32);
encryptor.Key = aesKey;
encryptor.IV = _iv;
==> print aesKey & _iv
...

AES encryption .Net to Android for mobile

I referred to the below link
AES Encryption .net to swift,
But, applying the same for ANDROID, I am not able to get the correct AES encryption with version(PBKDF2) conversion for my code. NEED HELP.
public static String Encrypt(String PlainText) throws Exception {
try {
byte[] salt = new byte[] { 0x49, 0x76, 0x61, 0x6E, 0x20, 0x4D,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 };
System.out.println("Exception setting up cipher: "+pbkdf2("<keyname>",salt.toString(),1024,128));
Cipher _aesCipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
byte[] keyBytes =pbkdf2("<keyname>",salt.toString(),1024,128).getBytes();
SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");
byte[] iv ="OFRna73m*aze01xY".getBytes();//pbkdf2("<keyname>",salt.toString(),2,64).getBytes();
IvParameterSpec ivSpec = new IvParameterSpec(iv);
_aesCipher.init(1, keySpec, ivSpec);
byte[] plainText = PlainText.getBytes();
byte[] result = _aesCipher.doFinal(plainText);
return Base64.encodeToString(result, Base64.DEFAULT);//Base64.encode(result,1));
} catch (Exception ex1) {
System.out.println("Exception setting up cipher: "
+ ex1.getMessage() + "\r\n");
ex1.printStackTrace();
return "";
}
}
public static String pbkdf2(String password, String salt, int iterations, int keyLength) throws NoSuchAlgorithmException, InvalidKeySpecException {
char[] chars = password.toCharArray();
PBEKeySpec spec = new PBEKeySpec(chars, salt.getBytes(), iterations, keyLength);
SecretKeyFactory skf = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
byte[] hash = skf.generateSecret(spec).getEncoded();
return toHex(hash);
}
// Converts byte array to a hexadecimal string
private static String toHex(byte[] array) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < array.length; i++) {
sb.append(Integer.toString((array[i] & 0xff) + 0x100, 16).substring(1));
}
return sb.toString();
}

Please check below code .
I have created Singletone class for the same so that i can access it anywhere in app.
Below Points Should be same like .net or swift
Important Points are IV , SALT and PASSWORD
Please check this too PBKDF2WithHmacSHA1
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
to generate key we used this
KeySpec spec = new PBEKeySpec(password, salt, 2, 256);
Importnant points are (password, salt,iterantion,bytes) this must be same like other platform which you are using with like .net or swift
public class AesBase64Wrapper {
private static String IV = "it should be same like server or other platform";
private static String PASSWORD = "it should be same like server or other platform";
private static String SALT = "it should be same like server or other platform";
private static volatile AesBase64Wrapper sSoleInstance = new AesBase64Wrapper();
//private constructor.
private AesBase64Wrapper() {
}
public static AesBase64Wrapper getInstance() {
return sSoleInstance;
}
// For Encryption
public String encryptAndEncode(String raw) {
try {
Cipher c = getCipher(Cipher.ENCRYPT_MODE);
byte[] encryptedVal = c.doFinal(getBytes(raw));
//String retVal = Base64.encodeToString(encryptedVal, Base64.DEFAULT);
String retVal = Base64.encodeToString(encryptedVal, Base64.NO_WRAP);
return retVal;
}catch (Throwable t) {
throw new RuntimeException(t);
}
}
public String decodeAndDecrypt(String encrypted) throws Exception {
// byte[] decodedValue = Base64.decode(getBytes(encrypted),Base64.DEFAULT);
byte[] decodedValue = Base64.decode(getBytes(encrypted), Base64.NO_WRAP);
Cipher c = getCipher(Cipher.DECRYPT_MODE);
byte[] decValue = c.doFinal(decodedValue);
return new String(decValue);
}
private String getString(byte[] bytes) throws UnsupportedEncodingException {
return new String(bytes, "UTF-8");
}
private byte[] getBytes(String str) throws UnsupportedEncodingException {
return str.getBytes("UTF-8");
}
private Cipher getCipher(int mode) throws Exception {
Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
byte[] iv = getBytes(IV);
String xyz = String.valueOf(generateKey());
Log.i("generateKey", xyz);
c.init(mode, generateKey(), new IvParameterSpec(iv));
return c;
}
private Key generateKey() throws Exception {
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
char[] password = PASSWORD.toCharArray();
byte[] salt = getBytes(SALT);
KeySpec spec = new PBEKeySpec(password, salt, 2, 256);
SecretKey tmp = factory.generateSecret(spec);
byte[] encoded = tmp.getEncoded();
byte b = encoded[1];
Log.e("Secrete Key", String.valueOf(encoded));
return new SecretKeySpec(encoded, "CBC");
}
}
In Activity you can use it like
String EncryptString = AesBase64Wrapper.getInstance().encryptAndEncode("hello");
String DecryptString = AesBase64Wrapper.getInstance().encryptAndEncode(EncryptString);
// You will Get Output in Decrypted String

Issue in sending encoded parameters on servlet

I am using this class for encoding/decoding:
public class enc_dec {
public static Cipher dcipher, ecipher;
public enc_dec() {
byte[] salt = { (byte) 0xA9, (byte) 0x9B, (byte) 0xC8, (byte) 0x32,
(byte) 0x56, (byte) 0x34, (byte) 0xE3, (byte) 0x03 };
int iterationCount = 19;
try {
// Generate a temporary key. In practice, you would save this key
// Encrypting with DES Using a Pass Phrase
KeySpec keySpec = new PBEKeySpec("".toCharArray(), salt,iterationCount);
SecretKey key = SecretKeyFactory.getInstance("PBEWithMD5AndDES")
.generateSecret(keySpec);
ecipher = Cipher.getInstance(key.getAlgorithm());
dcipher = Cipher.getInstance(key.getAlgorithm());
// Prepare the parameters to the cipthers
AlgorithmParameterSpec paramSpec = new PBEParameterSpec(salt,
iterationCount);
ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
} catch (Exception e) { }
}
// Encrpt Password
#SuppressWarnings("unused")
public String encrypt(String str) {
try {
// Encode the string into bytes using utf-8
byte[] utf8 = str.getBytes("UTF8");
// Encrypt
byte[] enc = ecipher.doFinal(utf8);
// Encode bytes to base64 to get a string
return new sun.misc.BASE64Encoder().encode(enc);
} catch (Exception e) {
}
return null;
}
// Decrpt password
// To decrypt the encryted password
public String decrypt(String str) {
Cipher dcipher = null;
try {
byte[] salt = { (byte) 0xA9, (byte) 0x9B, (byte) 0xC8, (byte) 0x32,
(byte) 0x56, (byte) 0x34, (byte) 0xE3, (byte) 0x03 };
int iterationCount = 19;
try {
String passPhrase = "";
KeySpec keySpec = new PBEKeySpec(passPhrase.toCharArray(),
salt, iterationCount);
SecretKey key = SecretKeyFactory
.getInstance("PBEWithMD5AndDES")
.generateSecret(keySpec);
dcipher = Cipher.getInstance(key.getAlgorithm());
// Prepare the parameters to the cipthers
AlgorithmParameterSpec paramSpec = new PBEParameterSpec(salt,
iterationCount);
dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
} catch (Exception e) {}
// Decode base64 to get bytes
byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str);
// Decrypt
byte[] utf8 = dcipher.doFinal(dec);
// Decode using utf-8
return new String(utf8, "UTF8");
} catch (Exception e) {
}
return null;
}
This is my URL-which i am sending from a JSP page:
http://localhost:8080/Sample_Project/send_encode.ENC?type=M0z7jTCb8PPfSZxfAdhw3Q==&payment=UxCU5BdZh4U=&sr_no=eN1X3XOeYuI=
This is my send_encode servlet:
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
HttpSession session=request.getSession(false);
if(session.getAttribute("session_set")!=null)
{
classes.enc_dec enc=new classes.enc_dec();
response.setContentType("text/html;charset=UTF-8");
PrintWriter out=response.getWriter();
String type=enc.decrypt(request.getParameter("type"));
String payment=enc.decrypt(request.getParameter("payment"));
long sr_no=Long.parseLong(request.getParameter("sr_no"));
try{
RequestDispatcher comprd = getServletContext().getRequestDispatcher("/new_page.jsp?type="+enc.encrypt(type)+"&payment="+enc.encrypt(payment)+"");
comprd.include(request, response);
}
catch(Exception e)
{
System.out.println("The ecxeption is "+e);
}
}
The exception I am facing is:
WARNING: StandardWrapperValve[send_encode]: Servlet.service() for servlet send_encode threw exception
java.lang.NumberFormatException: For input string: "eN1X3XOeYuI="
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Long.parseLong(Long.java:441)
at java.lang.Long.parseLong(Long.java:483)
at controller.send_encode.doGet(send_encode.java:30)
I have set encoding as UTF-8 but still i am getting the exception.I have also tried other questions posted on SO but unable to get any help.
Thanks in advance

Java Decyption logic throwing BadpaddingException But its working in .NET

.NET code
public String Decrypt(string encryptedString)
{
byte[] toEncryptArray = Convert.FromBase64String(encryptedString)
MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
byte[] keyArray = hashmd5.ComputeHash(System.Text.Encoding.Unicode.GetBytes(key));
hashmd5.Clear();
TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
tdes.Key = keyArray;
tdes.Mode = CipherMode.ECB;
tdes.Padding = PaddingMode.PKCS7;
ICryptoTransform cTransform = tdes.CreateDecryptor();
byte[] resultArray = cTransform.TransformFinalBlock(
toEncryptArray, 0, toEncryptArray.Length);
}
Java code
public void decryptin(String encryptedText) throws Exception{
byte[] message = Base64.decodeBase64(encryptedText.getBytes("UTF-8"));
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] digestOfUsername = md.digest(key.getBytes("UTF-8"));
byte[] keyBytes = Arrays.copyOf(digestOfUsername, 24);
SecretKey key = new SecretKeySpec(keyBytes, "DESede");
Cipher decipher = Cipher.getInstance("DESede/ECB/PKCS5Padding",new SunJCE());
decipher.init(Cipher.DECRYPT_MODE, key);
byte[] plainText = decipher.doFinal(message);// BadpaddingException
String decryptedString = new String(plainText);
}
.NET code working fine but java is code is not give the proper output
its giving BadpaddingException : at dofinal() please correct me where i am doing mistake.

Ok, so the problem is that you are converting the encrypted bytes to a hex string (using the asHex method) but are not converting the hex string back to a byte array correctly for decryption. You can't use getBytes.
You can use the following method to convert a hex string to a byte array:
public static byte[] fromHexString(String s) {
int len = s.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
return data;
}
and then change your decrypt method to use:
original = decipher.doFinal(fromHexString(message));

finally i got the ans :
public void decrypt(String encryptedText)throws Exception {
byte[] message = new BASE64Decoder().decodeBuffer(encryptedText);
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] digestOfPassword = md.digest(kEY.getBytes("UTF-16LE"));
byte[] keyBytes = new byte[24];
System.arraycopy(digestOfPassword, 0, keyBytes, 0, 16);
System.arraycopy(digestOfPassword, 0, keyBytes, 16, 8);
SecretKey key = new SecretKeySpec(keyBytes, "DESede");
Cipher decipher = Cipher.getInstance("DESede/ECB/PKCS5Padding");
decipher.init(Cipher.DECRYPT_MODE, key);
byte[] plainText = decipher.doFinal(message);
String decryptedString = new String(plainText, UTF);
}

BOUNCY CAStLE AES 256 decryption problem in java

Really a buggy question , hee is the code:
import java.io.IOException;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
public class Encryption {
public static final int a = 0x9F224;
public static final int b = 0x98C36;
public static final int c = 0x776a2;
public static final int d = 0x87667;
private String preMaster;
IvParameterSpec ivSpec = new IvParameterSpec(new byte[] { 0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x02, 0x03, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x01 });
private byte[] text;
private SecretKey secret;
private byte[] sKey;
protected SecretKey passwordKey;
protected PBEParameterSpec paramSpec;
public static final String ENCYT_ALGORITHM = "AES/CBC/PKCS7Padding";
public static final String KEY_ALGORITHM = "PBEWITHSHA256AND256BITAES-CBC-BC" ;
//BENCYT_ALGORITHMSE64Encoder encod = new BENCYT_ALGORITHMSE64Encoder();
//BENCYT_ALGORITHMSE64Decoder decod = new BENCYT_ALGORITHMSE64Decoder();
public Encryption(String preMaster,String text,int x){
this.preMaster=preMaster;
this.text=Encoder.decode(text.toCharArray());
try {
KeyGenerator kg = KeyGenerator.getInstance("AES");
kg.init(256);
secret = kg.generateKey();
} catch (Exception e) {
// TODO ENCYT_ALGORITHMuto-generated catch block
e.printStackTrace();
}
}
public Encryption(String key,String text){
try {
this.text = Encoder.decode(text.toCharArray());
this.sKey = Encoder.decode(key.toCharArray());
} catch (Exception e) {
e.printStackTrace();
}
}
public String preMaster() {
byte[] keys = null;
keys = preMaster.getBytes();
int x = -1;
int process = 0;
while (x < keys.length - 2) {
x++;
switch (x) {
case 1:
process = keys[x + 1] | a ^ c & (d | keys[x] % a);
case 2:
process += a | (keys[x] ^ c) & d;
case 3:
process += keys[x] ^ (keys[x + 1] / a) % d ^ b;
default:
process += keys[x + 1] / (keys[x] ^ c | d);
}
}
byte[] xs = new byte[] { (byte) (process >>> 24),
(byte) (process >> 16 & 0xff), (byte) (process >> 8 & 0xff),
(byte) (process & 0xff) };
preMaster = new String(xs);
KeyGenerators key = new KeyGenerators(preMaster);
String toMaster = key.calculateSecurityHash("MD5")
+ key.calculateSecurityHash("MD2")
+ key.calculateSecurityHash("SHA-512");
return toMaster;
}
public String keyWrapper(){
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
Key SharedKey = secret;
String key = null;
char[] preMaster = this.preMaster().toCharArray();
try {
byte[]salt={ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06};
paramSpec = new PBEParameterSpec(salt,20);
PBEKeySpec keySpec = new PBEKeySpec(preMaster);
SecretKeyFactory factory = SecretKeyFactory.getInstance(KEY_ALGORITHM);
passwordKey = factory.generateSecret(keySpec);
Cipher c = Cipher.getInstance(KEY_ALGORITHM);
c.init(Cipher.WRAP_MODE, passwordKey, paramSpec);
byte[] wrappedKey = c.wrap(SharedKey);
key=Encoder.encode(wrappedKey);
}catch(Exception e){
e.printStackTrace();
}
return key;
}
public Key KeyUnwrapper(){
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] wrappedKey = sKey;
Key unWrapped = null;
try{
Cipher c = Cipher.getInstance(KEY_ALGORITHM,"BC");
c.init(Cipher.UNWRAP_MODE, passwordKey, paramSpec);
unWrapped = c.unwrap(wrappedKey, ENCYT_ALGORITHM, Cipher.SECRET_KEY);
}catch(Exception e){
e.printStackTrace();
}
return unWrapped;
}
public String encrypt(){
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
SecretKey key = secret;
String result=null;
try{
Cipher cipher = Cipher.getInstance(ENCYT_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, key);
result =Encoder.encode(cipher.doFinal(text));
}catch(Exception e){
e.printStackTrace();
}
return result;
}
public String decrypt(){
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
String result = null;
SecretKey key = (SecretKey) KeyUnwrapper();
try{
Cipher cipher = Cipher.getInstance(ENCYT_ALGORITHM, "BC");
cipher.init(Cipher.DECRYPT_MODE, key);
result = Encoder.encode(cipher.doFinal(text));
}catch(Exception e){
e.printStackTrace();
}
return result;
}
public static void main(String[] args) throws IOException{
Encryption en = new Encryption("123456","Hello World",0);
String enText = en.encrypt();
String key = en.keyWrapper();
System.out.println(key);
System.out.println(enText);
Encryption de = new Encryption(key,enText);
String plainText = de.decrypt();
System.out.println(plainText);
}
And , this is the result ... i tried all the combinations i can, but none of them works ..
F63DE3EE8CEECF4DF76836CA6D69A3903BD87B5726656C54C1C8EC30B6653B2C0E5C7672BE3CF4BE7B2DC7AC5D07DEA0
F1C8D92E5F74019C569D54D70045ADD6
java.lang.NullPointerException
at org.bouncycastle.jce.provider.JCEBlockCipher.engineInit(Unknown Source)
at javax.crypto.Cipher.init(DashoA13*..)
at javax.crypto.Cipher.init(DashoA13*..)
at fiador.authentication.util.Encryption.KeyUnwrapper(Encryption.java:114)
at fiador.authentication.util.Encryption.decrypt(Encryption.java:142)
at fiador.authentication.util.Encryption.main(Encryption.java:160)
java.lang.NullPointerException
at org.bouncycastle.jce.provider.JCEBlockCipher.engineInit(Unknown Source)
at javax.crypto.Cipher.a(DashoA13*..)
at javax.crypto.Cipher.a(DashoA13*..)
at javax.crypto.Cipher.init(DashoA13*..)
at javax.crypto.Cipher.init(DashoA13*..)
at fiador.authentication.util.Encryption.decrypt(Encryption.java:145)
at fiador.authentication.util.Encryption.main(Encryption.java:160)
null

The first NullPointerException occurs inside this method call (in the KeyUnwrapper method):
c.init(Cipher.UNWRAP_MODE, passwordKey, paramSpec);
Have a look: Could one of these arguments be null?
Looking at the code, it seems like passwordKey is only assigned to in keyWrapper, but this is not called on this instance of your class.