aes.py

• https://github.com/dhuertas/AES 를 참고하여 python으로 구현하였습니다.
• FIPS 197, Advanced Encryption Standard (AES) 를 참고하여 공부했습니다.

Plaintest message: 32 43 f6 a8 88 5a 30 8d 31 31 98 a2 e0 37 07 34

Ciphered message: 39 25 84 1d 02 dc 09 fb dc 11 85 97 19 6a 0b 32

Original message (after inv cipher): 32 43 f6 a8 88 5a 30 8d 31 31 98 a2 e0 37 07 34

AES128_/over_GF.py

def aes_gmult(a, b) - xtime

def mul_inverse(a) - for i in range(1, 256): aes_gmult(a, i) = 1

def affine_trans(x) - over GF(2) : b_i'

def mix_columns(state) - xtime

AES128_/EEA_matrix.py

def aes_gmult(a, b) - polynomial mod m(x)

def mul_inverse(a) - Extended Euclidean Algorithm

def affine_trans(x) - matrix form

def mix_columns(state) - matrix form

function file /aes_gmult_inverse.py

def aes_gmult(a, b)

1. polynomial mod m(x)
2. xtime

def mul_inverse(a)

1. for i in range(1, 256): aes_gmult(a, i) = 1
2. Extended Euclidean Algorithm

function file /affine_trans.py

def affine_trans(x)

1. matrix form
2. over GF(2) : b_i'

function file /mix_columns.py

def mix_columns(state)

1. matrix form
2. xtime