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Java

AES Encryption ECB Mode with PKCS7 Padding

See more Encryption Examples

Duplicates the following C# code:
public static byte[] DecryptBySymmetricKey(string encryptedText, byte[] key)
  {
     string keyAsBase64 = Convert.ToBase64String(key);

     byte[] dataToDecrypt = Convert.FromBase64String(encryptedText);
     var keyBytes = key;
     AesManaged tdes = new AesManaged();
     tdes.KeySize = 256;
     tdes.BlockSize = 128;
     tdes.Key = keyBytes;
     tdes.Mode = CipherMode.ECB;
     tdes.Padding = PaddingMode.PKCS7;
     ICryptoTransform decrypt__1 = tdes.CreateDecryptor();
     byte[] deCipher = decrypt__1.TransformFinalBlock(dataToDecrypt, 0, dataToDecrypt.Length);
     tdes.Clear();
     string EK_result = Convert.ToBase64String(deCipher);
     return EK_result;
}

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt = new CkCrypt2();

    // In the C# code above that is to be duplicated here, use the base64 encoded key.
    String keyAsBase64 = "...";
    String encryptedBytesAsBase64 = "....";

    crypt.put_KeyLength(256);
    crypt.put_CryptAlgorithm("AES");
    crypt.put_CipherMode("ecb");
    crypt.put_PaddingScheme(0);
    crypt.SetEncodedKey(keyAsBase64,"base64");

    crypt.put_EncodingMode("base64");

    // Pass the base64 representation of the encrypted data.
    // (The EncodingMode indicates you are passing base64.)
    String EK_result = crypt.decryptStringENC(encryptedBytesAsBase64);

    System.out.println(EK_result);
  }
}