AES Cipher Key Strength in BlackBerry

Question

Hi All,

I need to create an application that decrypts data that is encrypted using AES with a 512-bit key. What I need to know is whether we can create an AES key of length 512-bits? The documentation says we can create a key of length up to 256-bits. If that is the case, is there any way that I can add my own implementation for 512-bit AES key, or will I have to reduce the key strength used to encrypt the data originally?

Thanks,

Basilio

Answer 1

AES is defined to accept a key of 128, 192 or 256 bits. If you stuff a 512-bit key into a cipher then that cipher cannot be AES.

Also, if using a 256-bit key for symmetric encryption is an actual "strength reduction" from what you get with a 512-bit key, then this means that you are in the habit of breaking known Laws of physics. Consequently, you are either a god, or somewhat delusional.