def encrypt(self, message, key=None):
key = key or self.key
N = len(key)
result = [''] * len(message)
for i, char in enumerate(message):
result[i] = shift_char(
char, key[i % N]) if key[i % N] != '_' else key[i % N]
return ''.join(result)
def caesar_cipher_encrypt(input_stream, output_stream, shift, decode=False):
if decode:
shift *= -1
while True:
buffer = input_stream.read(READ_WRITE_BUFFER_SIZE)
if not buffer:
break
output_buffer = ''.join(shift_char(c, shift) for c in buffer)
output_stream.write(output_buffer)
def vigenere_cipher_encrypt(input_stream, output_stream, key, decode=False):
key_digits = map(lambda x: get_char_num(x), key)
if decode:
key_digits = list(map(lambda x: -x, key_digits))
j = 0
while True:
buffer = input_stream.read(READ_WRITE_BUFFER_SIZE)
if not buffer:
break
output_buffer_chars = []
for c in buffer:
shift = key_digits[j % len(key_digits)]
output_buffer_chars.append(shift_char(c, shift))
j += 1
output_stream.write(''.join(output_buffer_chars))
def translate_reverse(self, char):
cumulative_rotor_rotation = self._window_position + self.ring_setting
shift_index = shift_num(alphaord(char), cumulative_rotor_rotation)
return shift_char(char, self.reverse_shifts[shift_index])
def translate_forward(self, char):
cumulative_rotor_rotation = 0
shift_index = shift_num(alphaord(char), cumulative_rotor_rotation)
return shift_char(char, self.forward_shifts[shift_index])
def encrypt_shift(self, text, key=None):
'''
C = (P + K) % 26
'''
key = self.key if key is None else key
return "".join(shift_char(char, key) for char in text)
def model_similarity_metric(curr_model, base_model, curr_model_shift=0):
return sum(
model_value_similarity(
value, base_model.get(shift_char(char, curr_model_shift), 0))
for char, value in curr_model.items())
def translate(self, char):
return shift_char(char, self.shifts[alphaord(char)])