* Fix compile errors with MacOS
- _POSIX_C_SOURCE must not be defined for num_CPU()
* separate util_posix.c require changes in tools directory as well
* remove unnecessary self-include
This implements the attack described in
Carlo Meijer, Roel Verdult, "Ciphertext-only Cryptanalysis on Hardened
Mifare Classic Cards" in Proceedings of the 22nd ACM SIGSAC Conference on
Computer and Communications Security, 2015
It uses precomputed tables for many bitflip properties (not only two as in the paper)
and is therefore quite efficient. To prevent failing it doesn't do
differential analysis with several nonce bytes' Sum(a8) properties (each of them
may be wrongly guessed) - instead it concentrates on one nonce byte and tries all
Sum(a8) property guesses sequentially (ordered by probability). The brute force phase
makes use of aczid's bit sliced brute forcer (https://github.com/aczid/crypto1_bs).
Includes runtime CPU-detection to leverage modern (and old) SIMD instructions
with a single executable.
