I have to decrypt text in JAVA, encrypted in C# (AES, RijndaelManaged).
After several days of reading and searching solutions, and a lot of stackoverflow solutions tested, i still have a problem unsolved.
I apply C# code here (which is working) and the java code (which not fully working).
Here is the exception from the java code:
Exception in thread "main" javax.crypto.IllegalBlockSizeException: last block incomplete in decryption
at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher.engineDoFinal(Unknown Source)
at javax.crypto.Cipher.doFinal(Cipher.java:2164)
at test.Decrypt.main(Decrypt.java:39)
JAVA code
import java.nio.charset.StandardCharsets;
import java.security.spec.KeySpec;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
public class Decrypt {
public static void main(String[] args) throws Exception {
String encText = "EAAAADE2ODA2NjQya2JNN2M1ISShgi+Oi5tbsPgOz5KsCHj0";
final String password = "KJH#$@kds32@!kjhdkftt";
final String iv = "16806642kbM7c5!$";
byte[] salt = new byte[] { 34, (byte) 134, (byte) 145, 12, 7, 6, (byte) 243, 63, 43, 54, 75, 65, 53, 2, 34, 54,
45, 67, 64, 64, 32, (byte) 213 };
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
KeySpec spec = new PBEKeySpec(password.toCharArray(), salt, 1000, 256);
SecretKey tmp = factory.generateSecret(spec);
SecretKeySpec secret = new SecretKeySpec(tmp.getEncoded(), "AES");
IvParameterSpec ivs = new IvParameterSpec(iv.getBytes(StandardCharsets.US_ASCII));
System.out.println("Key:" + Base64.getEncoder().encodeToString(secret.getEncoded()));
System.out.println("IV:" + Base64.getEncoder().encodeToString(ivs.getIV()));
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
cipher.init(Cipher.DECRYPT_MODE, secret, ivs);
byte [] decodedText = Base64.getDecoder().decode(encText);
String plaintext = new String(cipher.doFinal(decodedText), "UTF-8");
System.out.println(plaintext);
}
}
C# code
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
namespace Test
{
public class EncriptionHelper
{
public static void Main()
{
var cleanTxt = "8212093345";
var encTxt = "EAAAADE2ODA2NjQya2JNN2M1ISShgi+Oi5tbsPgOz5KsCHj0";
var secret = "KJH#$@kds32@!kjhdkftt";
var xtxt = EncryptStringAES(cleanTxt, secret);
var txt = DecryptStringAES(encTxt, secret);
Console.WriteLine(txt);
Console.WriteLine(xtxt);
}
private static byte[] vector = Encoding.ASCII.GetBytes("16806642kbM7c5!$");
private static byte[] salt = new byte[] { 34, 134, 145, 12, 7, 6, 243, 63, 43, 54, 75, 65, 53, 2, 34, 54, 45, 67, 64, 64, 32, 213 };
/// <summary>
/// Encrypt the given string using AES. The string can be decrypted using
/// DecryptStringAES(). The sharedSecret parameters must match.
public static string EncryptStringAES(string text, string sharedSecret)
{
if (string.IsNullOrEmpty(text))
{
throw new ArgumentNullException("Text is null or empty");
}
if (string.IsNullOrEmpty(sharedSecret))
{
throw new ArgumentNullException("Secret is null or empty");
}
if (salt == null || salt.Length == 0)
{
throw new ArgumentNullException("Salt is null or empty");
}
string outStr = null;
RijndaelManaged aesAlg = null;
try
{
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, salt);
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
aesAlg.IV = vector;
ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
using (MemoryStream msEncrypt = new MemoryStream())
{
msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
swEncrypt.Write(text);
}
}
outStr = Convert.ToBase64String(msEncrypt.ToArray());
}
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
// Return the encrypted bytes from the memory stream.
return outStr;
}
/// <summary>
/// Decrypt the given string. Assumes the string was encrypted using
/// EncryptStringAES(), using an identical sharedSecret.
/// </summary>
public static string DecryptStringAES(string cipherText, string sharedSecret)
{
if (string.IsNullOrEmpty(cipherText))
{
throw new ArgumentNullException("Text is null or empty");
}
if (string.IsNullOrEmpty(sharedSecret))
{
throw new ArgumentNullException("Secret is null or empty");
}
if (salt == null || salt.Length == 0)
{
throw new ArgumentNullException("Salt is null or empty");
}
RijndaelManaged aesAlg = null;
string result = null;
try
{
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, salt);
byte[] bytes = Convert.FromBase64String(cipherText);
using (MemoryStream msDecrypt = new MemoryStream(bytes))
{
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
aesAlg.IV = ReadByteArray(msDecrypt);
Console.WriteLine("KEY: "+ Convert.ToBase64String(aesAlg.Key));
Console.WriteLine("IV: "+ Convert.ToBase64String(aesAlg.IV));
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
result = srDecrypt.ReadToEnd();
}
}
}
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
return result;
}
private static byte[] ReadByteArray(Stream s)
{
byte[] rawLength = new byte[sizeof(int)];
if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
{
throw new SystemException("Stream did not contain properly formatted byte array");
}
byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
if (s.Read(buffer, 0, buffer.Length) != buffer.Length)
{
throw new SystemException("Did not read byte array properly");
}
return buffer;
}
}
}
