import collections
import norms
import logging
-from itertools import zip_longest, cycle, permutations
+import random
+from itertools import zip_longest, cycle, permutations, starmap
from segment import segment
from multiprocessing import Pool
from math import log10
import matplotlib.pyplot as plt
+logger = logging.getLogger(__name__)
+logger.addHandler(logging.FileHandler('cipher.log'))
+logger.setLevel(logging.WARNING)
+#logger.setLevel(logging.INFO)
+#logger.setLevel(logging.DEBUG)
+
from cipher import *
from language_models import *
frequency analysis
>>> keyword_break(keyword_encipher('this is a test message for the ' \
- 'keyword decipherment', 'elephant', 1), \
+ 'keyword decipherment', 'elephant', Keyword_wrap_alphabet.from_last), \
wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
- (('elephant', 1), -52.834575011...)
+ (('elephant', <Keyword_wrap_alphabet.from_last: 2>), -52.834575011...)
"""
best_keyword = ''
best_wrap_alphabet = True
best_fit = float("-inf")
- for wrap_alphabet in range(3):
+ for wrap_alphabet in Keyword_wrap_alphabet:
for keyword in wordlist:
plaintext = keyword_decipher(message, keyword, wrap_alphabet)
fit = fitness(plaintext)
frequency analysis
>>> keyword_break_mp(keyword_encipher('this is a test message for the ' \
- 'keyword decipherment', 'elephant', 1), \
+ 'keyword decipherment', 'elephant', Keyword_wrap_alphabet.from_last), \
wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
- (('elephant', 1), -52.834575011...)
+ (('elephant', <Keyword_wrap_alphabet.from_last: 2>), -52.834575011...)
"""
with Pool() as pool:
helper_args = [(message, word, wrap, fitness)
- for word in wordlist for wrap in range(3)]
+ for word in wordlist
+ for wrap in Keyword_wrap_alphabet]
# Gotcha: the helper function here needs to be defined at the top level
# (limitation of Pool.starmap)
breaks = pool.starmap(keyword_break_worker, helper_args, chunksize)
wrap_alphabet, fit, sanitise(plaintext)[:50]))
return (keyword, wrap_alphabet), fit
-def scytale_break(message, fitness=Pbigrams):
- """Breaks a Scytale cipher
-
- >>> scytale_break('tfeulchtrtteehwahsdehneoifeayfsondmwpltmaoalhikotoere' \
- 'dcweatehiplwxsnhooacgorrcrcraotohsgullasenylrendaianeplscdriioto' \
- 'aek') # doctest: +ELLIPSIS
- (6, -281.276219108...)
- """
- best_key = 0
- best_fit = float("-inf")
- for key in range(1, 20):
- if len(message) % key == 0:
- plaintext = scytale_decipher(message, key)
- fit = fitness(sanitise(plaintext))
- logger.debug('Scytale break attempt using key {0} gives fit of '
- '{1} and decrypt starting: {2}'.format(key,
- fit, sanitise(plaintext)[:50]))
- if fit > best_fit:
- best_fit = fit
- best_key = key
- logger.info('Scytale break best fit with key {0} gives fit of {1} and '
- 'decrypt starting: {2}'.format(best_key, best_fit,
- sanitise(scytale_decipher(message, best_key))[:50]))
- return best_key, best_fit
+def monoalphabetic_break_hillclimbing(message, max_iterations = 10000000,
+ fitness=Pletters):
+ ciphertext = unaccent(message).lower()
+ alphabet = list(string.ascii_lowercase)
+ random.shuffle(alphabet)
+ alphabet = ''.join(alphabet)
+ return monoalphabetic_break_hillclimbing_worker(ciphertext, alphabet,
+ max_iterations, fitness)
+
+def monoalphabetic_break_hillclimbing_mp(message, workers=10,
+ max_iterations = 10000000, fitness=Pletters, chunksize=1):
+ worker_args = []
+ ciphertext = unaccent(message).lower()
+ for i in range(workers):
+ alphabet = list(string.ascii_lowercase)
+ random.shuffle(alphabet)
+ alphabet = ''.join(alphabet)
+ worker_args.append((ciphertext, alphabet, max_iterations, fitness))
+ with Pool() as pool:
+ breaks = pool.starmap(monoalphabetic_break_hillclimbing_worker,
+ worker_args, chunksize)
+ return max(breaks, key=lambda k: k[1])
+
+def monoalphabetic_break_hillclimbing_worker(message, alphabet,
+ max_iterations, fitness):
+ def swap(letters, i, j):
+ if i > j:
+ i, j = j, i
+ if i == j:
+ return letters
+ else:
+ return letters[:i] + letters[j] + letters[i+1:j] + letters[i] + letters[j+1:]
+ best_alphabet = alphabet
+ best_fitness = float('-inf')
+ for i in range(max_iterations):
+ alphabet = swap(alphabet, random.randrange(26), random.randrange(26))
+ cipher_translation = ''.maketrans(string.ascii_lowercase, alphabet)
+ plaintext = message.translate(cipher_translation)
+ if fitness(plaintext) > best_fitness:
+ best_fitness = fitness(plaintext)
+ best_alphabet = alphabet
+ print(i, best_alphabet, best_fitness, plaintext)
+ return best_alphabet, best_fitness
def column_transposition_break_mp(message, translist=transpositions,
fitness=Pbigrams, chunksize=500):
"""Breaks a column transposition cipher using a dictionary and
n-gram frequency analysis
+
+ >>> column_transposition_break_mp(column_transposition_encipher(sanitise( \
+ "It is a truth universally acknowledged, that a single man in \
+ possession of a good fortune, must be in want of a wife. However \
+ little known the feelings or views of such a man may be on his \
+ first entering a neighbourhood, this truth is so well fixed in the \
+ minds of the surrounding families, that he is considered the \
+ rightful property of some one or other of their daughters."), \
+ 'encipher'), \
+ translist={(2, 0, 5, 3, 1, 4, 6): ['encipher'], \
+ (5, 0, 6, 1, 3, 4, 2): ['fourteen'], \
+ (6, 1, 0, 4, 5, 3, 2): ['keyword']}) # doctest: +ELLIPSIS
+ (((2, 0, 5, 3, 1, 4, 6), False, False), -709.4646722...)
+ >>> column_transposition_break_mp(column_transposition_encipher(sanitise( \
+ "It is a truth universally acknowledged, that a single man in \
+ possession of a good fortune, must be in want of a wife. However \
+ little known the feelings or views of such a man may be on his \
+ first entering a neighbourhood, this truth is so well fixed in the \
+ minds of the surrounding families, that he is considered the \
+ rightful property of some one or other of their daughters."), \
+ 'encipher'), \
+ translist={(2, 0, 5, 3, 1, 4, 6): ['encipher'], \
+ (5, 0, 6, 1, 3, 4, 2): ['fourteen'], \
+ (6, 1, 0, 4, 5, 3, 2): ['keyword']}, \
+ fitness=Ptrigrams) # doctest: +ELLIPSIS
+ (((2, 0, 5, 3, 1, 4, 6), False, False), -997.0129085...)
"""
- # >>> column_transposition_break_mp(column_transposition_encipher(sanitise( \
- # "It is a truth universally acknowledged, that a single man in \
- # possession of a good fortune, must be in want of a wife. However \
- # little known the feelings or views of such a man may be on his \
- # first entering a neighbourhood, this truth is so well fixed in the \
- # minds of the surrounding families, that he is considered the \
- # rightful property of some one or other of their daughters."), \
- # 'encipher'), \
- # translist={(2, 0, 5, 3, 1, 4, 6): ['encipher'], \
- # (5, 0, 6, 1, 3, 4, 2): ['fourteen'], \
- # (6, 1, 0, 4, 5, 3, 2): ['keyword']}) # doctest: +ELLIPSIS
- # (((2, 0, 5, 3, 1, 4, 6), False), 0.0628106372...)
- # >>> column_transposition_break_mp(column_transposition_encipher(sanitise( \
- # "It is a truth universally acknowledged, that a single man in \
- # possession of a good fortune, must be in want of a wife. However \
- # little known the feelings or views of such a man may be on his \
- # first entering a neighbourhood, this truth is so well fixed in the \
- # minds of the surrounding families, that he is considered the \
- # rightful property of some one or other of their daughters."), \
- # 'encipher'), \
- # translist={(2, 0, 5, 3, 1, 4, 6): ['encipher'], \
- # (5, 0, 6, 1, 3, 4, 2): ['fourteen'], \
- # (6, 1, 0, 4, 5, 3, 2): ['keyword']}, \
- # target_counts=normalised_english_trigram_counts) # doctest: +ELLIPSIS
- # (((2, 0, 5, 3, 1, 4, 6), False), 0.0592259560...)
- # """
with Pool() as pool:
- helper_args = [(message, trans, columnwise, fitness)
+ helper_args = [(message, trans, fillcolumnwise, emptycolumnwise,
+ fitness)
for trans in translist.keys()
- for columnwise in [True, False]]
+ for fillcolumnwise in [True, False]
+ for emptycolumnwise in [True, False]]
# Gotcha: the helper function here needs to be defined at the top level
# (limitation of Pool.starmap)
breaks = pool.starmap(column_transposition_break_worker,
return max(breaks, key=lambda k: k[1])
column_transposition_break = column_transposition_break_mp
-def column_transposition_break_worker(message, transposition, columnwise,
- fitness):
- plaintext = column_transposition_decipher(message, transposition, columnwise=columnwise)
+def column_transposition_break_worker(message, transposition,
+ fillcolumnwise, emptycolumnwise, fitness):
+ plaintext = column_transposition_decipher(message, transposition,
+ fillcolumnwise=fillcolumnwise, emptycolumnwise=emptycolumnwise)
fit = fitness(sanitise(plaintext))
logger.debug('Column transposition break attempt using key {0} '
'gives fit of {1} and decrypt starting: {2}'.format(
transposition, fit,
sanitise(plaintext)[:50]))
- return (transposition, columnwise), fit
-
-
-def transposition_break_exhaustive(message, fitness=Pbigrams):
- best_transposition = ''
- best_pw = float('-inf')
- for keylength in range(1, 21):
- if len(message) % keylength == 0:
- for transposition in permutations(range(keylength)):
- for columnwise in [True, False]:
- plaintext = column_transposition_decipher(message,
- transposition, columnwise=columnwise)
- fit=fitness(plaintext)
- logger.debug('Column transposition break attempt using key {0} {1} '
- 'gives fit of {2} and decrypt starting: {3}'.format(
- transposition, columnwise, pw,
- sanitise(plaintext)[:50]))
- if fit > best_fit:
- best_transposition = transposition
- best_columnwise = columnwise
- best_fit = fit
- return (best_transposition, best_columnwise), best_pw
+ return (transposition, fillcolumnwise, emptycolumnwise), fit
-def vigenere_keyword_break(message, wordlist=keywords, fitness=Pletters):
- """Breaks a vigenere cipher using a dictionary and
- frequency analysis
-
- >>> vigenere_keyword_break(vigenere_encipher(sanitise('this is a test ' \
- 'message for the vigenere decipherment'), 'cat'), \
- wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
- ('cat', -52.947271216...)
+def scytale_break_mp(message, max_key_length=20,
+ fitness=Pbigrams, chunksize=500):
+ """Breaks a scytale cipher using a range of lengths and
+ n-gram frequency analysis
+
+ >>> scytale_break_mp(scytale_encipher(sanitise( \
+ "It is a truth universally acknowledged, that a single man in \
+ possession of a good fortune, must be in want of a wife. However \
+ little known the feelings or views of such a man may be on his \
+ first entering a neighbourhood, this truth is so well fixed in the \
+ minds of the surrounding families, that he is considered the \
+ rightful property of some one or other of their daughters."), \
+ 5)) # doctest: +ELLIPSIS
+ (5, -709.4646722...)
+ >>> scytale_break_mp(scytale_encipher(sanitise( \
+ "It is a truth universally acknowledged, that a single man in \
+ possession of a good fortune, must be in want of a wife. However \
+ little known the feelings or views of such a man may be on his \
+ first entering a neighbourhood, this truth is so well fixed in the \
+ minds of the surrounding families, that he is considered the \
+ rightful property of some one or other of their daughters."), \
+ 5), \
+ fitness=Ptrigrams) # doctest: +ELLIPSIS
+ (5, -997.0129085...)
"""
- best_keyword = ''
- best_fit = float("-inf")
- for keyword in wordlist:
- plaintext = vigenere_decipher(message, keyword)
- fit = fitness(plaintext)
- logger.debug('Vigenere break attempt using key {0} '
- 'gives fit of {1} and decrypt starting: {2}'.format(
- keyword, fit,
- sanitise(plaintext)[:50]))
- if fit > best_fit:
- best_fit = fit
- best_keyword = keyword
- logger.info('Vigenere break best fit with key {0} gives fit '
- 'of {1} and decrypt starting: {2}'.format(best_keyword,
- best_fit, sanitise(
- vigenere_decipher(message, best_keyword))[:50]))
- return best_keyword, best_fit
+ with Pool() as pool:
+ helper_args = [(message, trans, False, True, fitness)
+ for trans in
+ [[col for col in range(math.ceil(len(message)/rows))]
+ for rows in range(1,max_key_length+1)]]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(column_transposition_break_worker,
+ helper_args, chunksize)
+ best = max(breaks, key=lambda k: k[1])
+ return math.trunc(len(message) / len(best[0][0])), best[1]
+scytale_break = scytale_break_mp
+
def vigenere_keyword_break_mp(message, wordlist=keywords, fitness=Pletters,
chunksize=500):
# (limitation of Pool.starmap)
breaks = pool.starmap(vigenere_keyword_break_worker, helper_args, chunksize)
return max(breaks, key=lambda k: k[1])
+vigenere_keyword_break = vigenere_keyword_break_mp
def vigenere_keyword_break_worker(message, keyword, fitness):
plaintext = vigenere_decipher(message, keyword)
-def vigenere_frequency_break(message, fitness=Pletters):
+def vigenere_frequency_break(message, max_key_length=20, fitness=Pletters):
"""Breaks a Vigenere cipher with frequency analysis
>>> vigenere_frequency_break(vigenere_encipher(sanitise("It is time to " \
"sure"), 'florence')) # doctest: +ELLIPSIS
('florence', -307.5473096791...)
"""
- best_fit = float("-inf")
- best_key = ''
- sanitised_message = sanitise(message)
- for trial_length in range(1, 20):
- splits = every_nth(sanitised_message, trial_length)
+ def worker(message, key_length, fitness):
+ splits = every_nth(sanitised_message, key_length)
key = ''.join([chr(caesar_break(s)[0] + ord('a')) for s in splits])
- plaintext = vigenere_decipher(sanitised_message, key)
+ plaintext = vigenere_decipher(message, key)
fit = fitness(plaintext)
- logger.debug('Vigenere key length of {0} ({1}) gives fit of {2}'.
- format(trial_length, key, fit))
- if fit > best_fit:
- best_fit = fit
- best_key = key
- logger.info('Vigenere break best fit with key {0} gives fit '
- 'of {1} and decrypt starting: {2}'.format(best_key,
- best_fit, sanitise(
- vigenere_decipher(message, best_key))[:50]))
- return best_key, best_fit
-
-def beaufort_frequency_break(message, fitness=Pletters):
+ return key, fit
+ sanitised_message = sanitise(message)
+ results = starmap(worker, [(sanitised_message, i, fitness)
+ for i in range(1, max_key_length+1)])
+ return max(results, key=lambda k: k[1])
+
+
+def beaufort_frequency_break(message, max_key_length=20, fitness=Pletters):
"""Breaks a Beaufort cipher with frequency analysis
>>> beaufort_frequency_break(beaufort_encipher(sanitise("It is time to " \
"that he is sure"), 'florence')) # doctest: +ELLIPSIS
('florence', -307.5473096791...)
"""
- best_fit = float("-inf")
- best_key = ''
- sanitised_message = sanitise(message)
- for trial_length in range(1, 20):
- splits = every_nth(sanitised_message, trial_length)
+ def worker(message, key_length, fitness):
+ splits = every_nth(sanitised_message, key_length)
key = ''.join([chr(-caesar_break(s)[0] % 26 + ord('a')) for s in splits])
- plaintext = beaufort_decipher(sanitised_message, key)
+ plaintext = beaufort_decipher(message, key)
fit = fitness(plaintext)
- logger.debug('Beaufort key length of {0} ({1}) gives fit of {2}'.
- format(trial_length, key, fit))
- if fit > best_fit:
- best_fit = fit
- best_key = key
- logger.info('Beaufort break best fit with key {0} gives fit '
- 'of {1} and decrypt starting: {2}'.format(best_key,
- best_fit, sanitise(
- beaufort_decipher(message, best_key))[:50]))
- return best_key, best_fit
-
+ return key, fit
+ sanitised_message = sanitise(message)
+ results = starmap(worker, [(sanitised_message, i, fitness)
+ for i in range(1, max_key_length+1)])
+ return max(results, key=lambda k: k[1])
+
+
+def pocket_enigma_break_by_crib(message, wheel_spec, crib, crib_position):
+ """Break a pocket enigma using a crib (some plaintext that's expected to
+ be in a certain position). Returns a list of possible starting wheel
+ positions that could produce the crib.
+
+ >>> pocket_enigma_break_by_crib('kzpjlzmoga', 1, 'h', 0)
+ ['a', 'f', 'q']
+ >>> pocket_enigma_break_by_crib('kzpjlzmoga', 1, 'he', 0)
+ ['a']
+ >>> pocket_enigma_break_by_crib('kzpjlzmoga', 1, 'll', 2)
+ ['a']
+ >>> pocket_enigma_break_by_crib('kzpjlzmoga', 1, 'l', 2)
+ ['a']
+ >>> pocket_enigma_break_by_crib('kzpjlzmoga', 1, 'l', 3)
+ ['a', 'j', 'n']
+ >>> pocket_enigma_break_by_crib('aaaaa', 1, 'l', 3)
+ []
+ """
+ pe = PocketEnigma(wheel=wheel_spec)
+ possible_positions = []
+ for p in string.ascii_lowercase:
+ pe.set_position(p)
+ plaintext = pe.decipher(message)
+ if plaintext[crib_position:crib_position+len(crib)] == crib:
+ possible_positions += [p]
+ return possible_positions
def plot_frequency_histogram(freqs, sort_key=None):
projects / cipher-training.git / blobdiff