aes.h

Can this file be rewritten so it does not explicitly define AES128, AES192, or AES256 within the file? It should simply default to AES128 if not defined. Simply remove the following statements completely:
#define AES128 1
//#define AES192 1
//#define AES256 1

Allow the compiler to define the symbol and its value. The reason I ask, is that I'd like to use your library "as is" with no modifications whatsoever yet allow the flexibility of using it in AES256 or AES192 mode.

Start with aes.h and inspect how AES128, AES192, and AES256 are currently defined and selected. Remove the explicit definitions described in the issue while preserving AES128 as the default when no symbol is supplied, then verify that compiler-provided AES192 and AES256 selections remain possible.

Written by the indexing model from the issue text.