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Working with AES Encryption Java to C#

We have the application done C# and passing parameter to Java application. To make it secure we Java application developer come up with AES encryption. The developer gave sample code in Java. Kindly somebody helps me. How can I encrypt same way in C#
// Cryptix imports
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import cryptix.provider.key.RawSecretKey;
import cryptix.util.core.Hex;
import xjava.security.Cipher;
public class AESEncryption {
private Cipher m_alg;
private RawSecretKey m_key;
private static final String RIJNDAEL = "Rijndael"; //mode of encryption
private static final String PROVIDER_CRYPTIX = "Cryptix"; // Cryptography algorithm providers
/**
* Must (once) be dynamically installed. - could alternatively be set
* statically in $JAVAHOME/lib/security by changing security provider.
*
*/
static {
java.security.Security.addProvider(new cryptix.provider.Cryptix());
System.out.println(" Java Security - Add security provider - Cryptix provider added");
}
public AESEncryption(String secretKey)
throws java.security.NoSuchProviderException, java.security.NoSuchAlgorithmException {
//System.out.println("Key used for encryption/decryption :- " + secretKey);
m_alg = Cipher.getInstance(RIJNDAEL, PROVIDER_CRYPTIX);
m_key = new RawSecretKey(RIJNDAEL, Hex.fromString(secretKey));
}
/**
* encrypt supplied string.
*
* #param str to encrypted
* #return encrypted String
*/
public String encrypt(String str) throws java.security.KeyException {
byte[] ect = null;
str = convert(str); // pad if necessary
//System.out.println("String to encrypt [ " + str + " ]");
m_alg.initEncrypt(m_key);
ect = m_alg.crypt(str.getBytes());
//System.out.println("Encrypted String [ " + Hex.toString(ect) + " ]");
return Hex.toString(ect);
}
public String decrypt(String str) throws java.security.KeyException {
byte[] dct = null;
String decryptedString;
//System.out.println("String to decrypt [ " + str + " ]");
m_alg.initDecrypt(m_key);
dct = m_alg.crypt(Hex.fromString(str));
decryptedString = new String(dct);
//System.out.println("Decrypted String [ " + decryptedString + " ]");
return decryptedString.trim();
}
/**
* Internal routine to convert a string to a byte array and to
* pad the byte array (with 0) in order ot fill out the final block.
*
* padding value based on Cipher's defined block size.
*
* #param str
* #return
*/
private String convert(String str) {
int padding = 0, sourceLength = 0, i, blockSize;
sourceLength = str.length();
blockSize = m_alg.blockSize();
padding = blockSize - (sourceLength % blockSize);
if (padding != blockSize) {
for (i = 0; i < padding; i++) {
str = str + " ";
}
}
return str;
}
public static void main(String[] args) {
try {
AESEncryption tcase = new AESEncryption("27323A0825226DDD316881852610DACB81210355C3117DAD83EF5EE9E8602915");
String params ="accentué";
System.out.println("Params Before:" + params);
String encrypted = tcase.encrypt(params);
System.out.println("Params Encrypted:" + encrypted);
String enc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
//String decrypted = tcase.decrypt(encrypted);
String decrypted = tcase.decrypt(enc);
System.out.println("Params Decrypted:" + decrypted);
} catch (NoSuchProviderException e) {
e.printStackTrace();
} catch (java.security.KeyException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
}

İf you used IV vector in c# while encrypted data with AES . You should use IV vector in Java
c#
using (var random = new System.Security.Cryptography.RNGCryptoServiceProvider())
{
var key = new byte[16];
random.GetBytes(key);
using (System.Security.Cryptography.AesCryptoServiceProvider aesAlg = new System.Security.Cryptography.AesCryptoServiceProvider())
{
aesAlg.BlockSize = 128;
aesAlg.KeySize = 128;
aesAlg.Key = key;
aesAlg.IV = key;
aesAlg.Mode = System.Security.Cryptography.CipherMode.CBC;
aesAlg.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
using (ICryptoTransform iCryptoper = aesAlg.CreateEncryptor())
{
byte[] encryptedData = iCryptoper.TransformFinalBlock(x509CertData, 0, x509CertData.Length);
string encodedCert = Convert.ToBase64String(encryptedData);
System.Security.Cryptography.X509Certificates.X509Certificate2 x509Cert = new System.Security.Cryptography.X509Certificates.X509Certificate2(x509CertData);
System.Security.Cryptography.RSACryptoServiceProvider provider = (System.Security.Cryptography.RSACryptoServiceProvider)x509Cert.PublicKey.Key;
byte[] encrypted = provider.Encrypt(aesAlg.Key, false);
string test = Convert.ToBase64String(encrypted);
}
}
}
java
javax.crypto.SecretKey sc = new javax.crypto.spec.SecretKeySpec(secretKey, "AES");
Cipher dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
IvParameterSpec ivParameterSpec = new IvParameterSpec(iv);
dcipher.init(Cipher.DECRYPT_MODE, sc, ivParameterSpec);
byte[] decyrptedCert = dcipher.doFinal(java.util.Base64.getDecoder().decode(stringToDecrypt));

Convert Java MessageDigest code snippet to C#

The java code below generates a SHA-256 hash of the input msg, using the key. However, all my attempts to write code that does same operation in C# have not yielded the same results given same input. I would need help getting the C# equivalent as I have tried a lot already with little success.
I think I've been able to translate most of the code into C# correctly, apart from the part which updates the digest (m.update()), first with the key, then later with the message before hashing.
JAVA CODE
public static String generateHash256Value(String msg, String key) {
MessageDigest m = null;
String hashText = null;
System.out.println("Value to hash::::::::::" + msg);
byte[] actualKeyBytes = HexToByte(secret_key);
try {
m = MessageDigest.getInstance("SHA-256");
m.update(actualKeyBytes, 0, actualKeyBytes.length);
try {
m.update(msg.getBytes("UTF-8"), 0, msg.length());
}
catch (UnsupportedEncodingException ex) {
ex.printStackTrace();
}
hashText = new BigInteger(1, m.digest()).toString(16);
if (hashText.length() < 64) { //must be 64 in length
int numberOfZeroes = 64 - hashText.length();
String zeroes = "";
for (int i = 0; i < numberOfZeroes; i++) {
zeroes = zeroes + "0";
}
hashText = zeroes + hashText;
}
}
catch (NoSuchAlgorithmException ex) {
ex.printStackTrace();
}
hashText = hashText.toUpperCase();
return hashText;
}
public static byte[] hex2Byte(String str) {
byte[] bytes = new byte[str.length() / 2];
for (int i = 0; i < bytes.length; i++) {
bytes[i] = (byte) Integer
.parseInt(str.substring(2 * i, 2 * i + 2), 16);
}
return bytes;
}
C# CODE (attempt)
private static string DoSpecialSha256Hash(string message, string key)
{
String hashText = null;
Console.WriteLine("Value to hash::::::::::" + message);
byte[] keyByte = hex2Byte(key);
Encoding encoder = new System.Text.UTF8Encoding();
var hashAlgo = new SHA256Managed();
var messageBytes = encoder.GetBytes(message);
var toDigest = Combine(keyByte, messageBytes);
hashText = ByteToString(hashAlgo.ComputeHash(toDigest, 0, message.Length));
if (hashText.Length < 64)
{ //must be 64 in length
int numberOfZeroes = 64 - hashText.Length;
String zeroes = "";
for (int i = 0; i < numberOfZeroes; i++)
{
zeroes = zeroes + "0";
}
hashText = zeroes + hashText;
}
hashText = hashText.ToUpper();
return hashText;
}
public static byte[] HexToByte(String hex)
{
return Enumerable.Range(0, hex.Length)
.Where(x => x % 2 == 0)
.Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
.ToArray();
}
private static string ByteToString(byte[] buff)
{
string sbinary = "";
for (int i = 0; i < buff.Length; i++)
{
sbinary += buff[i].ToString("X2"); // hex format
}
return (sbinary);
}
private static byte[] Combine(params byte[][] arrays)
{
byte[] rv = new byte[arrays.Sum(a => a.Length)];
int offset = 0;
foreach (byte[] array in arrays)
{
System.Buffer.BlockCopy(array, 0, rv, offset, array.Length);
offset += array.Length;
}
return rv;
}
Thanks,

convert byte array to string in java

I try to convert byte array to string in java using new String( bytes, "UTF-8") method, but they only return the object. like this #AB4634bSbbfa
So, I searched some way to solve this problem.
I finally get valid string array, by converting hex-code to basic-character array.
like this. char[] chars = {"0", "1", ... "e", "f"};
This never happened before why do i have to convert hex-code to get valid string.
Here is method.
byte array which is hashed by Mac-sha-256 with specific key when i hashed.
public static String getHashString() {
String algorithm = "HmacSHA256";
String hashKey = "some_key";
String message = "abcdefg";
String hexed = "";
try {
Mac sha256_HMAC = Mac.getInstance(algorithm);
SecretKeySpec secret_key = new SecretKeySpec(hashKey.getBytes(), algorithm);
sha256_HMAC.init(secret_key);
byte[] hash = sha256_HMAC.doFinal(message.getBytes("UTF-8"));
// it doesn't work for me.
// hexed = new String(hash, "UTF-8");
// it works.
hexed = bytesToHex(hash);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return hexed;
}
public static final char[] HEX_DIGITS = "0123456789abcdef".toCharArray();
public static String bytesToHex(final byte[] data ) {
final int l = data.length;
final char[] hexChars = new char[l<<1];
for( int i=0, j =0; i < l; i++ ) {
hexChars[j++] = HEX_DIGITS[(0xF0 & data[i]) >>> 4];
hexChars[j++] = HEX_DIGITS[0x0F & data[i]];
}
return new String(hexChars);
}
Thanks.

Following is a sample which shows Conversion of Byte array to String :-
public class TestByte
{
public static void main(String[] argv) {
String example = "This is an example";
byte[] bytes = example.getBytes();
System.out.println("Text : " + example);
System.out.println("Text [Byte Format] : " + bytes);
System.out.println("Text [Byte Format] : " + bytes.toString());
String s = new String(bytes);
System.out.println("Text Decryted : " + s);
}}

I'm not sure the string you get in the end is what you're after. I think a common scenario is to use
new BASE64Encoder().encode(hash)
which will return you the hashed message as String.

just do new String(byteArray);

Java Aes class convert to php

Java code :
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
public class AESSecurityUtil {
private static final String AES = "AES";
private static final String CHARSET_NAME = "utf-8";
private static SecretKeySpec getKey(String password) throws NoSuchAlgorithmException{
KeyGenerator kgen = KeyGenerator.getInstance(AES);
SecureRandom random=SecureRandom.getInstance("SHA1PRNG");
random.setSeed(password.getBytes());
kgen.init(128, random);
SecretKey secretKey = kgen.generateKey();
byte[] enCodeFormat = secretKey.getEncoded();
SecretKeySpec key = new SecretKeySpec(enCodeFormat, AES);
return key;
}
public static String encode(String str, String password)
{
byte[] arr = encodeToArr(str, password);
return byteArrToString(arr);
}
private static byte[] encodeToArr(String str, String password)
{
try
{
Cipher cipher = Cipher.getInstance(AES);
byte[] byteContent = str.getBytes(CHARSET_NAME);
cipher.init(Cipher.ENCRYPT_MODE, getKey(password));
byte[] result = cipher.doFinal(byteContent);
return result;
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
public static String decode(String hexStr, String password){
byte[] arr = string2ByteArr(hexStr);
return decode(arr, password);
}
private static String decode(byte[] arr, String password) {
try{
Cipher cipher = Cipher.getInstance(AES);
cipher.init(Cipher.DECRYPT_MODE, getKey(password));
byte[] result = cipher.doFinal(arr);
return new String(result, CHARSET_NAME);
}catch (Exception e){
e.printStackTrace();
}
return null;
}
private static String byteArrToString(byte[] arr) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i <arr.length; i++) {
String s = Integer.toString(arr[i] + 128, 16);
if (s.length() == 1){
s = "0" + s;
}
sb.append(s);
}
return sb.toString().toUpperCase();
}
private static byte[] string2ByteArr(String s) {
s = s.toUpperCase();
String str = "0123456789ABCDEF";
byte[] arr = new byte[s.length() / 2];
for (int i = 0; i <arr.length; i++){
char s1 = s.charAt(i * 2);
char s2 = s.charAt(i * 2 + 1);
int tmp1 = str.indexOf(s1) * 16;
int tmp2 = str.indexOf(s2);
arr[i] = (byte) (tmp1 + tmp2 - 128);
}
return arr;
}
public static void main(String[] args) throws Exception {
System.out.println(decode("03AB8A3B85AFDD3926850B14C1BFF608", "imcc"));
String keyStr = "UITN25LMUQC436IM";
String plainText = "this is a string will be AES_Encrypt";
String encText = encode(plainText,keyStr);
String decString = decode(encText,keyStr);
System.out.println(encText);
System.out.println(decString);
}
}
Does the class can turn into a php code to achieve encryption and decryption ? I think the problem is that the getKey method can not achieve in php.
This Java class, provided by the platform side, can not require making changes.
Please tell me where the problem is?
Thanks
Append ...my PHP code:
<?php
if (!function_exists('hex2bin')) {
function hex2bin($str) {
$sbin = "";
$len = strlen($str);
for ($i = 0; $i < $len; $i += 2) {
$sbin .= pack("H*", substr($str, $i, 2));
}
return $sbin;
}
}
class Util_AesEncrypt {
private $_cipher = MCRYPT_RIJNDAEL_128;
private $_mode = MCRYPT_MODE_ECB;
private function _pkcs5Pad($text, $blockSize) {
$pad = $blockSize - (strlen($text) % $blockSize);
return $text . str_repeat(chr($pad), $pad);
}
private function _pkcs5Unpad($text) {
$end = substr($text, -1);
$last = ord($end);
$len = strlen($text) - $last;
if (substr($text, $len) == str_repeat($end, $last)) {
return substr($text, 0, $len);
}
return false;
}
public function encrypt($encrypt, $key) {
$blockSize = mcrypt_get_block_size($this->_cipher, $this->_mode);
$paddedData = $this->_pkcs5Pad($encrypt, $blockSize);
$ivSize = mcrypt_get_iv_size($this->_cipher, $this->_mode);
$iv = mcrypt_create_iv($ivSize, MCRYPT_RAND);
$encrypted = mcrypt_encrypt($this->_cipher, $key, $paddedData, $this->_mode, $iv);
return bin2hex($encrypted);
}
public function decrypt($decrypt, $key) {
$decoded = hex2bin($decrypt);
$blockSize = mcrypt_get_iv_size($this->_cipher, $this->_mode);
$iv = mcrypt_create_iv($blockSize, MCRYPT_RAND);
$decrypted = mcrypt_decrypt($this->_cipher, $key, $decoded, $this->_mode, $iv);
return $this->_pkcs5Unpad($decrypted);
}
}
$keyStr = 'UITN25LMUQC436IM';
$plainText = 'this is a string will be AES_Encrypt';
$aes = new Util_AesEncrypt();
$encText = $aes->encrypt($plainText, $keyStr);
$decString = $aes->decrypt($encText, $keyStr);
echo $encText, "\n", $decString;
Different encryption results

The JAVA getKey() function will get 128bit key from password use SHA1PRNG, you can use this PHP code to get key from password:
$key = substr(openssl_digest(openssl_digest($password, 'sha1', true), 'sha1', true), 0, 16);
I also spent a lot of time in this case, Good Luck.

Convert HMAC-SHA256 function from Java to Ruby

I'm trying to convert this hashing function to Ruby from Java.
Java code:
Mac localMac = "HMAC-SHA256";
String str1 = "a4d1b77bbb1a4a5ca695ad72c84b77e5";
localMac.init(new SecretKeySpec(str1.getBytes("UTF-8"), localMac.getAlgorithm()));
byte[] arrayOfByte = localMac.doFinal("{"_uid":"3396112","_csrftoken":"a23482932482sdsf4428","media_id":"616150302791211280_187036957"}");
BigInteger localBigInteger = new BigInteger(1, arrayOfByte);
String str3 = String.format("%0" + (arrayOfByte.length << 1) + "x", new Object[] { localBigInteger });
return str3;
Ruby code:
require 'openssl'
require 'base64'
secret = "a4d1b77bbb1a4a5ca695ad72c84b77e5"
digest = OpenSSL::Digest::Digest.new('sha256')
hash = OpenSSL::HMAC.hexdigest(digest, secret,'{"_uid":"3396112","_csrftoken":"a23482932482sdsf4428","media_id":"616150302791211280_187036957"}')
p hash
For some reason the hashes are never the same. Any help?

You can do it like this
public static void main(String[] args) {
String str1 = "a4d1b77bbb1a4a5ca695ad72c84b77e5";
byte[] keyBytes = str1.getBytes();
SecretKeySpec localMac = new SecretKeySpec(
keyBytes, "HmacSHA256");
final String inputStr = "{\"_uid\":\"3396112\",\"_csrftoken\":"
+ "\"a23482932482sdsf4428\","
+ "\"media_id\":\"616150302791211280_187036957\"}";
try {
Mac mac = Mac.getInstance("HmacSHA256");
mac.init(localMac);
// Compute the hmac on input data bytes
byte[] arrayOfByte = mac.doFinal(inputStr
.getBytes());
BigInteger localBigInteger = new BigInteger(1,
arrayOfByte);
String str3 = String.format("%0"
+ (arrayOfByte.length << 1) + "x",
new Object[] { localBigInteger });
System.out.println(str3);
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (IllegalStateException e) {
e.printStackTrace();
}
}
Which will output e48d690dc6825e8f2895845be112fb1e5ee22f5283f2243512d6cca2714e8b35.
$ cat test.rb
#!/usr/bin/env ruby
require 'openssl'
require 'base64'
secret = "a4d1b77bbb1a4a5ca695ad72c84b77e5"
digest = OpenSSL::Digest::Digest.new('sha256')
hash = OpenSSL::HMAC.hexdigest(digest, secret,'{"_uid":"3396112","_csrftoken":"a23482932482sdsf4428","media_id":"616150302791211280_187036957 "}')
p hash
$ ./test.rb
"e48d690dc6825e8f2895845be112fb1e5ee22f5283f2243512d6cca2714e8b35"