import matplotlib.pyplot as plt
-logger = logging.getLogger(__name__)
-logger.addHandler(logging.FileHandler('cipher.log'))
+# logging.basicConfig(filename="cipher.log", level=logging.INFO)
+# logger = logging.getLogger(__name__)
+
+logger = logging.getLogger('cipherbreak')
logger.setLevel(logging.WARNING)
-#logger.setLevel(logging.INFO)
-#logger.setLevel(logging.DEBUG)
+# logger.setLevel(logging.INFO)
+# logger.setLevel(logging.DEBUG)
+
+# create the logging file handler
+fh = logging.FileHandler("cipher.log")
+formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
+fh.setFormatter(formatter)
+
+# add handler to logger object
+logger.addHandler(fh)
+
from cipher import *
from language_models import *
if not alphabet:
alphabet = list(string.ascii_lowercase)
random.shuffle(alphabet)
- alphabet = ''.join(alphabet)
+ alphabet = cat(alphabet)
return monoalphabetic_break_hillclimbing_worker(ciphertext, alphabet,
max_iterations, fitness)
else:
this_alphabet = list(string.ascii_lowercase)
random.shuffle(this_alphabet)
- this_alphabet = ''.join(this_alphabet)
+ this_alphabet = cat(this_alphabet)
worker_args.append((ciphertext, this_alphabet, max_iterations, fitness))
with Pool() as pool:
breaks = pool.starmap(monoalphabetic_break_hillclimbing_worker,
"""
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])
+ key = cat([chr(caesar_break(s)[0] + ord('a')) for s in splits])
plaintext = vigenere_decipher(message, key)
fit = fitness(plaintext)
return key, fit
"""
def worker(message, key_length, fitness):
splits = every_nth(sanitised_message, key_length)
- key = ''.join([chr(-caesar_break(s)[0] % 26 + ord('a'))
+ key = cat([chr(-caesar_break(s)[0] % 26 + ord('a'))
for s in splits])
plaintext = beaufort_decipher(message, key)
fit = fitness(plaintext)
fit, sanitise(plaintext)[:50]))
return matrix, fit
+def bifid_break_mp(message, wordlist=keywords, fitness=Pletters, max_period=10,
+ number_of_solutions=1, chunksize=500):
+ """Breaks a keyword substitution cipher using a dictionary and
+ frequency analysis
+
+ >>> bifid_break_mp(bifid_encipher('this is a test message for the ' \
+ 'keyword decipherment', 'elephant', wrap_alphabet=KeywordWrapAlphabet.from_last), \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
+ (('elephant', <KeywordWrapAlphabet.from_last: 2>, 0), -52.834575011...)
+ >>> bifid_break_mp(bifid_encipher('this is a test message for the ' \
+ 'keyword decipherment', 'elephant', wrap_alphabet=KeywordWrapAlphabet.from_last), \
+ wordlist=['cat', 'elephant', 'kangaroo'], \
+ number_of_solutions=2) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ [(('elephant', <KeywordWrapAlphabet.from_last: 2>, 0), -52.834575011...),
+ (('elephant', <KeywordWrapAlphabet.from_largest: 3>, 0), -52.834575011...)]
+ """
+ with Pool() as pool:
+ helper_args = [(message, word, wrap, period, fitness)
+ for word in wordlist
+ for wrap in KeywordWrapAlphabet
+ for period in range(max_period+1)]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(bifid_break_worker, helper_args, chunksize)
+ if number_of_solutions == 1:
+ return max(breaks, key=lambda k: k[1])
+ else:
+ return sorted(breaks, key=lambda k: k[1], reverse=True)[:number_of_solutions]
+
+def bifid_break_worker(message, keyword, wrap_alphabet, period, fitness):
+ plaintext = bifid_decipher(message, keyword, wrap_alphabet, period=period)
+ fit = fitness(plaintext)
+ logger.debug('Keyword break attempt using key {0} (wrap={1}) gives fit of '
+ '{2} and decrypt starting: {3}'.format(keyword,
+ wrap_alphabet, fit, sanitise(plaintext)[:50]))
+ return (keyword, wrap_alphabet, period), fit
+
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