Decrypting bytes encrypted by .NET's RijndaelManaged using Java

Question

I am trying to decrypt something, which was encrypted using RijndaelManaged of .NET/C#, using Java to decrypt.

The C# program is not mine; I cannot change it to be more

Answer 1

It's possible using the standard AES decryption. Rijndel is just a superset of AES which is more lax with particular options. See Rijndael support in Java for more details.

From the answer given in the linked question:

byte[] sessionKey = null; //Where you get this from is beyond the scope of this post
byte[] iv = null ; //Ditto
byte[] plaintext = null; //Whatever you want to encrypt/decrypt
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
//You can use ENCRYPT_MODE or DECRYPT_MODE
cipher.calling init(Cipher.DECRYPT_MODE, new SecretKeySpec(sessionKey, "AES"), new IvParameterSpec(iv));
byte[] ciphertext = cipher.doFinal(plaintext);