Krypto_Grundlagen/chapter_three/Lineares-Schieberegister.py
David Huh 46634275e4 Added Lineares Schieberegister
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2021-10-18 14:57:22 +02:00

42 lines
1.2 KiB
Python

from utils import CipherUtils
CLEAR_LIST = [0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1]
INIT_STATE = [0, 1, 1, 0]
COEFFICIENTS = [1, 1, 1, 0]
def create_shift_register(init_state: list, coefficients: list):
return_list = []
current_state = init_state.copy()
current_state_list = [current_state.copy()]
if (size := len(init_state)) != len(coefficients):
print('Length of lists does not match.')
exit()
for x in range(2 ** size):
return_list.append(current_state[-1])
new_state_value = 0
for i in range(size):
new_state_value = (new_state_value + current_state[i] ^ coefficients[i]) % 2
current_state.insert(0, new_state_value)
current_state.pop(-1)
if current_state in current_state_list:
return_list.extend(current_state[1:][::-1])
break
current_state_list.append(current_state.copy())
return return_list
if __name__ == '__main__':
key = create_shift_register(INIT_STATE, COEFFICIENTS)
encrypted = CipherUtils.xor_two_lists(CLEAR_LIST, key)
decrypted = CipherUtils.xor_two_lists(encrypted, key)
print(CLEAR_LIST)
print(encrypted)
print(decrypted)