--- /dev/null
+*~
+*doc
+*log
+/tmp
+/__pycache__/*
+*pyc
+.ipynb*
+*.sublime-workspace
+.directory/*
+
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
--- /dev/null
+MIT License
+
+Copyright (c) 2020 Neil Smith
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
--- /dev/null
+# Szyfow ciphers
+
+Various tools for encipher, deciphering, and breaking simple (manual) ciphers.
+
--- /dev/null
+import setuptools
+
+with open("README.md", "r") as fh:
+ long_description = fh.read()
+
+setuptools.setup(
+ name="szyfrow",
+ version="0.0.1",
+ author="Neil Smith",
+ author_email="neil.szyfrow@njae.me.uk",
+ description="Tools for using and breaking simple ciphers",
+ long_description=long_description,
+ long_description_content_type="text/markdown",
+ url="https://github.com/pypa/sampleproject",
+ packages=setuptools.find_packages(),
+ classifiers=[
+ "Programming Language :: Python :: 3",
+ "License :: OSI Approved :: MIT License",
+ "Operating System :: OS Independent",
+ ],
+ python_requires='>=3.6',
+)
--- /dev/null
+from support.utilities import *
+from support.language_models import *
+from logger import logger
+
+
+modular_division_table = {
+ (multiplier, (multiplier * plaintext) % 26): plaintext
+ for plaintext in range(26)
+ for multiplier in range(26)
+ }
+
+
+def affine_encipher_letter(accented_letter, multiplier=1, adder=0, one_based=True):
+ """Encipher a letter, given a multiplier and adder
+
+ >>> cat(affine_encipher_letter(l, 3, 5, True) \
+ for l in string.ascii_letters)
+ 'hknqtwzcfiloruxadgjmpsvybeHKNQTWZCFILORUXADGJMPSVYBE'
+ >>> cat(affine_encipher_letter(l, 3, 5, False) \
+ for l in string.ascii_letters)
+ 'filoruxadgjmpsvybehknqtwzcFILORUXADGJMPSVYBEHKNQTWZC'
+ """
+ letter = unaccent(accented_letter)
+ if letter in string.ascii_letters:
+ letter_number = pos(letter)
+ if one_based: letter_number += 1
+ cipher_number = (letter_number * multiplier + adder) % 26
+ if one_based: cipher_number -= 1
+ if letter in string.ascii_uppercase:
+ return unpos(cipher_number).upper()
+ else:
+ return unpos(cipher_number)
+ else:
+ return letter
+
+def affine_decipher_letter(letter, multiplier=1, adder=0, one_based=True):
+ """Encipher a letter, given a multiplier and adder
+
+ >>> cat(affine_decipher_letter(l, 3, 5, True) \
+ for l in 'hknqtwzcfiloruxadgjmpsvybeHKNQTWZCFILORUXADGJMPSVYBE')
+ 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
+ >>> cat(affine_decipher_letter(l, 3, 5, False) \
+ for l in 'filoruxadgjmpsvybehknqtwzcFILORUXADGJMPSVYBEHKNQTWZC')
+ 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
+ """
+ if letter in string.ascii_letters:
+ cipher_number = pos(letter)
+ if one_based: cipher_number += 1
+ # plaintext_number = (
+ # modular_division_table[multiplier]
+ # [(cipher_number - adder) % 26])
+ plaintext_number = (
+ modular_division_table[multiplier, (cipher_number - adder) % 26]
+ )
+ if one_based: plaintext_number -= 1
+ if letter in string.ascii_uppercase:
+ return unpos(plaintext_number).upper()
+ else:
+ return unpos(plaintext_number)
+ else:
+ return letter
+
+def affine_encipher(message, multiplier=1, adder=0, one_based=True):
+ """Encipher a message
+
+ >>> affine_encipher('hours passed during which jerico tried every ' \
+ 'trick he could think of', 15, 22, True)
+ 'lmyfu bkuusd dyfaxw claol psfaom jfasd snsfg jfaoe ls omytd jlaxe mh'
+ """
+ enciphered = [affine_encipher_letter(l, multiplier, adder, one_based)
+ for l in message]
+ return cat(enciphered)
+
+def affine_decipher(message, multiplier=1, adder=0, one_based=True):
+ """Decipher a message
+
+ >>> affine_decipher('lmyfu bkuusd dyfaxw claol psfaom jfasd snsfg ' \
+ 'jfaoe ls omytd jlaxe mh', 15, 22, True)
+ 'hours passed during which jerico tried every trick he could think of'
+ """
+ enciphered = [affine_decipher_letter(l, multiplier, adder, one_based)
+ for l in message]
+ return cat(enciphered)
+
+
+
+def affine_break(message, fitness=Pletters):
+ """Breaks an affine cipher using frequency analysis
+
+ >>> affine_break('lmyfu bkuusd dyfaxw claol psfaom jfasd snsfg jfaoe ls ' \
+ 'omytd jlaxe mh jm bfmibj umis hfsul axubafkjamx. ls kffkxwsd jls ' \
+ 'ofgbjmwfkiu olfmxmtmwaokttg jlsx ls kffkxwsd jlsi zg tsxwjl. jlsx ' \
+ 'ls umfjsd jlsi zg hfsqysxog. ls dmmdtsd mx jls bats mh bkbsf. ls ' \
+ 'bfmctsd kfmyxd jls lyj, mztanamyu xmc jm clm cku tmmeaxw kj lai ' \
+ 'kxd clm ckuxj.') # doctest: +ELLIPSIS
+ ((15, 22, True), -340.601181913...)
+ """
+ sanitised_message = sanitise(message)
+ best_multiplier = 0
+ best_adder = 0
+ best_one_based = True
+ best_fit = float("-inf")
+ for one_based in [True, False]:
+ for multiplier in [x for x in range(1, 26, 2) if x != 13]:
+ for adder in range(26):
+ plaintext = affine_decipher(sanitised_message,
+ multiplier, adder, one_based)
+ fit = fitness(plaintext)
+ logger.debug('Affine break attempt using key {0}x+{1} ({2}) '
+ 'gives fit of {3} and decrypt starting: {4}'.
+ format(multiplier, adder, one_based, fit,
+ plaintext[:50]))
+ if fit > best_fit:
+ best_fit = fit
+ best_multiplier = multiplier
+ best_adder = adder
+ best_one_based = one_based
+ logger.info('Affine break best fit with key {0}x+{1} ({2}) gives fit of '
+ '{3} and decrypt starting: {4}'.format(
+ best_multiplier, best_adder, best_one_based, best_fit,
+ affine_decipher(sanitised_message, best_multiplier,
+ best_adder, best_one_based)[:50]))
+ return (best_multiplier, best_adder, best_one_based), best_fit
--- /dev/null
+from enum import Enum
+import multiprocessing
+import itertools
+
+from support.utilities import *
+from support.language_models import *
+from cipher.column_transposition import transpositions, transpositions_of
+
+from logger import logger
+
+# Where each piece of text ends up in the AMSCO transpositon cipher.
+# 'index' shows where the slice appears in the plaintext, with the slice
+# from 'start' to 'end'
+AmscoSlice = collections.namedtuple('AmscoSlice', ['index', 'start', 'end'])
+
+class AmscoFillStyle(Enum):
+ continuous = 1
+ same_each_row = 2
+ reverse_each_row = 3
+
+def amsco_transposition_positions(message, keyword,
+ fillpattern=(1, 2),
+ fillstyle=AmscoFillStyle.continuous,
+ fillcolumnwise=False,
+ emptycolumnwise=True):
+ """Creates the grid for the AMSCO transposition cipher. Each element in the
+ grid shows the index of that slice and the start and end positions of the
+ plaintext that go to make it up.
+
+ >>> amsco_transposition_positions(string.ascii_lowercase, 'freddy', \
+ fillpattern=(1, 2)) # doctest: +NORMALIZE_WHITESPACE
+ [[AmscoSlice(index=3, start=4, end=6),
+ AmscoSlice(index=2, start=3, end=4),
+ AmscoSlice(index=0, start=0, end=1),
+ AmscoSlice(index=1, start=1, end=3),
+ AmscoSlice(index=4, start=6, end=7)],
+ [AmscoSlice(index=8, start=12, end=13),
+ AmscoSlice(index=7, start=10, end=12),
+ AmscoSlice(index=5, start=7, end=9),
+ AmscoSlice(index=6, start=9, end=10),
+ AmscoSlice(index=9, start=13, end=15)],
+ [AmscoSlice(index=13, start=19, end=21),
+ AmscoSlice(index=12, start=18, end=19),
+ AmscoSlice(index=10, start=15, end=16),
+ AmscoSlice(index=11, start=16, end=18),
+ AmscoSlice(index=14, start=21, end=22)],
+ [AmscoSlice(index=18, start=27, end=28),
+ AmscoSlice(index=17, start=25, end=27),
+ AmscoSlice(index=15, start=22, end=24),
+ AmscoSlice(index=16, start=24, end=25),
+ AmscoSlice(index=19, start=28, end=30)]]
+ """
+ transpositions = transpositions_of(keyword)
+ fill_iterator = itertools.cycle(fillpattern)
+ indices = itertools.count()
+ message_length = len(message)
+
+ current_position = 0
+ grid = []
+ current_fillpattern = fillpattern
+ while current_position < message_length:
+ row = []
+ if fillstyle == AmscoFillStyle.same_each_row:
+ fill_iterator = itertools.cycle(fillpattern)
+ if fillstyle == AmscoFillStyle.reverse_each_row:
+ fill_iterator = itertools.cycle(current_fillpattern)
+ for _ in range(len(transpositions)):
+ index = next(indices)
+ gap = next(fill_iterator)
+ row += [AmscoSlice(index, current_position, current_position + gap)]
+ current_position += gap
+ grid += [row]
+ if fillstyle == AmscoFillStyle.reverse_each_row:
+ current_fillpattern = list(reversed(current_fillpattern))
+ return [transpose(r, transpositions) for r in grid]
+
+def amsco_transposition_encipher(message, keyword,
+ fillpattern=(1,2), fillstyle=AmscoFillStyle.reverse_each_row):
+ """AMSCO transposition encipher.
+
+ >>> amsco_transposition_encipher('hellothere', 'abc', fillpattern=(1, 2))
+ 'hoteelhler'
+ >>> amsco_transposition_encipher('hellothere', 'abc', fillpattern=(2, 1))
+ 'hetelhelor'
+ >>> amsco_transposition_encipher('hellothere', 'acb', fillpattern=(1, 2))
+ 'hotelerelh'
+ >>> amsco_transposition_encipher('hellothere', 'acb', fillpattern=(2, 1))
+ 'hetelorlhe'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'encode')
+ 'etecstthhomoerereenisxip'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'cipher', fillpattern=(1, 2))
+ 'hetcsoeisterereipexthomn'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'cipher', fillpattern=(1, 2), fillstyle=AmscoFillStyle.continuous)
+ 'hecsoisttererteipexhomen'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'cipher', fillpattern=(2, 1))
+ 'heecisoosttrrtepeixhemen'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'cipher', fillpattern=(1, 3, 2))
+ 'hxtomephescieretoeisnter'
+ >>> amsco_transposition_encipher('hereissometexttoencipher', 'cipher', fillpattern=(1, 3, 2), fillstyle=AmscoFillStyle.continuous)
+ 'hxomeiphscerettoisenteer'
+ """
+ grid = amsco_transposition_positions(message, keyword,
+ fillpattern=fillpattern, fillstyle=fillstyle)
+ ct_as_grid = [[message[s.start:s.end] for s in r] for r in grid]
+ return combine_every_nth(ct_as_grid)
+
+
+def amsco_transposition_decipher(message, keyword,
+ fillpattern=(1,2), fillstyle=AmscoFillStyle.reverse_each_row):
+ """AMSCO transposition decipher
+
+ >>> amsco_transposition_decipher('hoteelhler', 'abc', fillpattern=(1, 2))
+ 'hellothere'
+ >>> amsco_transposition_decipher('hetelhelor', 'abc', fillpattern=(2, 1))
+ 'hellothere'
+ >>> amsco_transposition_decipher('hotelerelh', 'acb', fillpattern=(1, 2))
+ 'hellothere'
+ >>> amsco_transposition_decipher('hetelorlhe', 'acb', fillpattern=(2, 1))
+ 'hellothere'
+ >>> amsco_transposition_decipher('etecstthhomoerereenisxip', 'encode')
+ 'hereissometexttoencipher'
+ >>> amsco_transposition_decipher('hetcsoeisterereipexthomn', 'cipher', fillpattern=(1, 2))
+ 'hereissometexttoencipher'
+ >>> amsco_transposition_decipher('hecsoisttererteipexhomen', 'cipher', fillpattern=(1, 2), fillstyle=AmscoFillStyle.continuous)
+ 'hereissometexttoencipher'
+ >>> amsco_transposition_decipher('heecisoosttrrtepeixhemen', 'cipher', fillpattern=(2, 1))
+ 'hereissometexttoencipher'
+ >>> amsco_transposition_decipher('hxtomephescieretoeisnter', 'cipher', fillpattern=(1, 3, 2))
+ 'hereissometexttoencipher'
+ >>> amsco_transposition_decipher('hxomeiphscerettoisenteer', 'cipher', fillpattern=(1, 3, 2), fillstyle=AmscoFillStyle.continuous)
+ 'hereissometexttoencipher'
+ """
+
+ grid = amsco_transposition_positions(message, keyword,
+ fillpattern=fillpattern, fillstyle=fillstyle)
+ transposed_sections = [s for c in [l for l in zip(*grid)] for s in c]
+ plaintext_list = [''] * len(transposed_sections)
+ current_pos = 0
+ for slice in transposed_sections:
+ plaintext_list[slice.index] = message[current_pos:current_pos-slice.start+slice.end][:len(message[slice.start:slice.end])]
+ current_pos += len(message[slice.start:slice.end])
+ return cat(plaintext_list)
+
+
+def amsco_break(message, translist=transpositions, patterns = [(1, 2), (2, 1)],
+ fillstyles = [AmscoFillStyle.continuous,
+ AmscoFillStyle.same_each_row,
+ AmscoFillStyle.reverse_each_row],
+ fitness=Pbigrams,
+ chunksize=500):
+ """Breaks an AMSCO transposition cipher using a dictionary and
+ n-gram frequency analysis
+
+ >>> amsco_break(amsco_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']}, \
+ patterns=[(1, 2)]) # doctest: +ELLIPSIS
+ (((2, 0, 5, 3, 1, 4, 6), (1, 2), <AmscoFillStyle.continuous: 1>), -709.4646722...)
+ >>> amsco_break(amsco_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', fillpattern=(2, 1)), \
+ 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']}, \
+ patterns=[(1, 2), (2, 1)], fitness=Ptrigrams) # doctest: +ELLIPSIS
+ (((2, 0, 5, 3, 1, 4, 6), (2, 1), <AmscoFillStyle.continuous: 1>), -997.0129085...)
+ """
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, trans, pattern, fillstyle, fitness)
+ for trans in translist
+ for pattern in patterns
+ for fillstyle in fillstyles]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(amsco_break_worker, helper_args, chunksize)
+ return max(breaks, key=lambda k: k[1])
+
+def amsco_break_worker(message, transposition,
+ pattern, fillstyle, fitness):
+ plaintext = amsco_transposition_decipher(message, transposition,
+ fillpattern=pattern, fillstyle=fillstyle)
+ fit = fitness(sanitise(plaintext))
+ logger.debug('AMSCO transposition break attempt using key {0} and pattern'
+ '{1} ({2}) gives fit of {3} and decrypt starting: '
+ '{4}'.format(
+ transposition, pattern, fillstyle, fit,
+ sanitise(plaintext)[:50]))
+ return (transposition, pattern, fillstyle), fit
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+import math
+import multiprocessing
+from support.utilities import *
+from support.language_models import *
+from cipher.caesar import caesar_encipher_letter, caesar_decipher_letter
+
+from logger import logger
+
+
+def autokey_encipher(message, keyword):
+ """Encipher with the autokey cipher
+
+ >>> autokey_encipher('meetatthefountain', 'kilt')
+ 'wmpmmxxaeyhbryoca'
+ """
+ shifts = [pos(l) for l in keyword + message]
+ pairs = zip(message, shifts)
+ return cat([caesar_encipher_letter(l, k) for l, k in pairs])
+
+def autokey_decipher(ciphertext, keyword):
+ """Decipher with the autokey cipher
+
+ >>> autokey_decipher('wmpmmxxaeyhbryoca', 'kilt')
+ 'meetatthefountain'
+ """
+ plaintext = []
+ keys = list(keyword)
+ for c in ciphertext:
+ plaintext_letter = caesar_decipher_letter(c, pos(keys[0]))
+ plaintext += [plaintext_letter]
+ keys = keys[1:] + [plaintext_letter]
+ return cat(plaintext)
+
+
+
+def autokey_sa_break( message
+ , min_keylength=2
+ , max_keylength=20
+ , workers=10
+ , initial_temperature=200
+ , max_iterations=20000
+ , fitness=Pletters
+ , chunksize=1
+ , result_count=1
+ ):
+ """Break an autokey cipher by simulated annealing
+ """
+ worker_args = []
+ ciphertext = sanitise(message)
+ for keylength in range(min_keylength, max_keylength+1):
+ for i in range(workers):
+ key = cat(random.choice(string.ascii_lowercase) for _ in range(keylength))
+ worker_args.append((ciphertext, key,
+ initial_temperature, max_iterations, fitness))
+
+ with multiprocessing.Pool() as pool:
+ breaks = pool.starmap(autokey_sa_break_worker,
+ worker_args, chunksize)
+ if result_count <= 1:
+ return max(breaks, key=lambda k: k[1])
+ else:
+ return sorted(set(breaks), key=lambda k: k[1], reverse=True)[:result_count]
+
+
+def autokey_sa_break_worker(message, key,
+ t0, max_iterations, fitness):
+
+ temperature = t0
+
+ dt = t0 / (0.9 * max_iterations)
+
+ plaintext = autokey_decipher(message, key)
+ current_fitness = fitness(plaintext)
+ current_key = key
+
+ best_key = current_key
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+
+ # print('starting for', max_iterations)
+ for i in range(max_iterations):
+ swap_pos = random.randrange(len(current_key))
+ swap_char = random.choice(string.ascii_lowercase)
+
+ new_key = current_key[:swap_pos] + swap_char + current_key[swap_pos+1:]
+
+ plaintext = autokey_decipher(message, new_key)
+ new_fitness = fitness(plaintext)
+ try:
+ sa_chance = math.exp((new_fitness - current_fitness) / temperature)
+ except (OverflowError, ZeroDivisionError):
+ # print('exception triggered: new_fit {}, current_fit {}, temp {}'.format(new_fitness, current_fitness, temperature))
+ sa_chance = 0
+ if (new_fitness > current_fitness or random.random() < sa_chance):
+ # logger.debug('Simulated annealing: iteration {}, temperature {}, '
+ # 'current alphabet {}, current_fitness {}, '
+ # 'best_plaintext {}'.format(i, temperature, current_alphabet,
+ # current_fitness, best_plaintext[:50]))
+
+ # logger.debug('new_fit {}, current_fit {}, temp {}, sa_chance {}'.format(new_fitness, current_fitness, temperature, sa_chance))
+# print(new_fitness, new_key, plaintext[:100])
+ current_fitness = new_fitness
+ current_key = new_key
+
+ if current_fitness > best_fitness:
+ best_key = current_key
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+ if i % 500 == 0:
+ logger.debug('Simulated annealing: iteration {}, temperature {}, '
+ 'current key {}, current_fitness {}, '
+ 'best_plaintext {}'.format(i, temperature, current_key,
+ current_fitness, plaintext[:50]))
+ temperature = max(temperature - dt, 0.001)
+
+# print(best_key, best_fitness, best_plaintext[:70])
+ return best_key, best_fitness # current_alphabet, current_fitness
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+import multiprocessing
+from support.utilities import *
+from support.language_models import *
+from cipher.keyword_cipher import KeywordWrapAlphabet, keyword_cipher_alphabet_of
+
+from logger import logger
+
+def bifid_grid(keyword, wrap_alphabet, letter_mapping):
+ """Create the grids for a Bifid cipher
+ """
+ cipher_alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet)
+ if letter_mapping is None:
+ letter_mapping = {'j': 'i'}
+ translation = ''.maketrans(letter_mapping)
+ cipher_alphabet = cat(collections.OrderedDict.fromkeys(cipher_alphabet.translate(translation)))
+ f_grid = {k: ((i // 5) + 1, (i % 5) + 1)
+ for i, k in enumerate(cipher_alphabet)}
+ r_grid = {((i // 5) + 1, (i % 5) + 1): k
+ for i, k in enumerate(cipher_alphabet)}
+ return translation, f_grid, r_grid
+
+def bifid_encipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a,
+ letter_mapping=None, period=None, fillvalue=None):
+ """Bifid cipher
+
+ >>> bifid_encipher("indiajelly", 'iguana')
+ 'ibidonhprm'
+ >>> bifid_encipher("indiacurry", 'iguana', period=4)
+ 'ibnhgaqltm'
+ >>> bifid_encipher("indiacurry", 'iguana', period=4, fillvalue='x')
+ 'ibnhgaqltzml'
+ """
+ translation, f_grid, r_grid = bifid_grid(keyword, wrap_alphabet, letter_mapping)
+
+ t_message = message.translate(translation)
+ pairs0 = [f_grid[l] for l in sanitise(t_message)]
+ if period:
+ chunked_pairs = [pairs0[i:i+period] for i in range(0, len(pairs0), period)]
+ if len(chunked_pairs[-1]) < period and fillvalue:
+ chunked_pairs[-1] += [f_grid[fillvalue]] * (period - len(chunked_pairs[-1]))
+ else:
+ chunked_pairs = [pairs0]
+
+ pairs1 = []
+ for c in chunked_pairs:
+ items = sum(list(list(i) for i in zip(*c)), [])
+ p = [(items[i], items[i+1]) for i in range(0, len(items), 2)]
+ pairs1 += p
+
+ return cat(r_grid[p] for p in pairs1)
+
+
+def bifid_decipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a,
+ letter_mapping=None, period=None, fillvalue=None):
+ """Decipher with bifid cipher
+
+ >>> bifid_decipher('ibidonhprm', 'iguana')
+ 'indiaielly'
+ >>> bifid_decipher("ibnhgaqltm", 'iguana', period=4)
+ 'indiacurry'
+ >>> bifid_decipher("ibnhgaqltzml", 'iguana', period=4)
+ 'indiacurryxx'
+ """
+ translation, f_grid, r_grid = bifid_grid(keyword, wrap_alphabet, letter_mapping)
+
+ t_message = message.translate(translation)
+ pairs0 = [f_grid[l] for l in sanitise(t_message)]
+ if period:
+ chunked_pairs = [pairs0[i:i+period] for i in range(0, len(pairs0), period)]
+ if len(chunked_pairs[-1]) < period and fillvalue:
+ chunked_pairs[-1] += [f_grid[fillvalue]] * (period - len(chunked_pairs[-1]))
+ else:
+ chunked_pairs = [pairs0]
+
+ pairs1 = []
+ for c in chunked_pairs:
+ items = [j for i in c for j in i]
+ gap = len(c)
+ p = [(items[i], items[i+gap]) for i in range(gap)]
+ pairs1 += p
+
+ return cat(r_grid[p] for p in pairs1)
+
+
+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 multiprocessing.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
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+import string
+import collections
+import multiprocessing
+import itertools
+import logging
+
+from cipher.enigma import *
+
+
+logger = logging.getLogger('bombe')
+# logger.setLevel(logging.WARNING)
+# logger.setLevel(logging.INFO)
+logger.setLevel(logging.DEBUG)
+
+# create the logging file handler
+fh = logging.FileHandler("enigma.log")
+formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
+fh.setFormatter(formatter)
+
+# add handler to logger object
+logger.addHandler(fh)
+
+##################################
+# # Bombe
+##################################
+#
+# Good explanation of [how the bombe worked](http://www.ellsbury.com/enigmabombe.htm) by Graham Ellsbury
+#
+
+Signal = collections.namedtuple('Signal', ['bank', 'wire'])
+Connection = collections.namedtuple('Connection', ['banks', 'scrambler'])
+MenuItem = collections.namedtuple('MenuIem', ['before', 'after', 'number'])
+
+
+def make_menu(plaintext, ciphertext):
+ return [MenuItem(p, c, i+1)
+ for i, (p, c) in enumerate(zip(plaintext, ciphertext))]
+
+
+class Scrambler(object):
+ def __init__(self, wheel1_spec, wheel2_spec, wheel3_spec, reflector_spec,
+ wheel1_pos='a', wheel2_pos='a', wheel3_pos='a'):
+ self.wheel1 = SimpleWheel(wheel1_spec, position=wheel1_pos)
+ self.wheel2 = SimpleWheel(wheel2_spec, position=wheel2_pos)
+ self.wheel3 = SimpleWheel(wheel3_spec, position=wheel3_pos)
+ self.reflector = Reflector(reflector_spec)
+
+ def __getattribute__(self, name):
+ if name=='wheel_positions':
+ return self.wheel1.position, self.wheel2.position, self.wheel3.position
+ elif name=='wheel_positions_l':
+ return self.wheel1.position_l, self.wheel2.position_l, self.wheel3.position_l
+ else:
+ return object.__getattribute__(self, name)
+
+ def advance(self, wheel1=False, wheel2=False, wheel3=True):
+ if wheel1: self.wheel1.advance()
+ if wheel2: self.wheel2.advance()
+ if wheel3: self.wheel3.advance()
+
+ def lookup(self, letter):
+ a = self.wheel3.forward(letter)
+ b = self.wheel2.forward(a)
+ c = self.wheel1.forward(b)
+ d = self.reflector.forward(c)
+ e = self.wheel1.backward(d)
+ f = self.wheel2.backward(e)
+ g = self.wheel3.backward(f)
+ return g
+
+ def set_positions(self, wheel1_pos, wheel2_pos, wheel3_pos):
+ self.wheel1.set_position(wheel1_pos)
+ self.wheel2.set_position(wheel2_pos)
+ self.wheel3.set_position(wheel3_pos)
+
+
+class Bombe(object):
+
+ def __init__(self, wheel1_spec, wheel2_spec, wheel3_spec, reflector_spec,
+ menu=None, start_signal=None, use_diagonal_board=True,
+ verify_plugboard=True):
+ self.connections = []
+ self.wheel1_spec = wheel1_spec
+ self.wheel2_spec = wheel2_spec
+ self.wheel3_spec = wheel3_spec
+ self.reflector_spec = reflector_spec
+ if menu:
+ self.read_menu(menu)
+ if start_signal:
+ self.test_start = start_signal
+ self.use_diagonal_board = use_diagonal_board
+ self.verify_plugboard = verify_plugboard
+
+ def __getattribute__(self, name):
+ if name=='wheel_positions':
+ return self.connections[0].scrambler.wheel_positions
+ elif name=='wheel_positions_l':
+ return self.connections[0].scrambler.wheel_positions_l
+ else:
+ return object.__getattribute__(self, name)
+
+ def __call__(self, start_positions):
+ return start_positions, self.test(initial_signal=self.test_start,
+ start_positions=start_positions,
+ use_diagonal_board=self.use_diagonal_board,
+ verify_plugboard=self.verify_plugboard)
+
+ def add_connection(self, bank_before, bank_after, scrambler):
+ self.connections += [Connection([bank_before, bank_after], scrambler)]
+
+ def read_menu(self, menu):
+ self.connections = []
+ for item in menu:
+ scrambler = Scrambler(self.wheel1_spec, self.wheel2_spec, self.wheel3_spec,
+ self.reflector_spec,
+ wheel3_pos=unpos(item.number - 1))
+ self.add_connection(item.before, item.after, scrambler)
+ most_common_letter = (collections.Counter(m.before for m in menu) +\
+ collections.Counter(m.after for m in menu)).most_common(1)[0][0]
+ self.test_start = Signal(most_common_letter, most_common_letter)
+
+ def set_positions(self, wheel1_pos, wheel2_pos, wheel3_pos):
+ for i, c in enumerate(self.connections):
+ c.scrambler.set_positions(wheel1_pos, wheel2_pos, unpos(pos(wheel3_pos) + i))
+
+ def test(self, initial_signal=None, start_positions=None, use_diagonal_board=True,
+ verify_plugboard=True):
+ self.banks = {label:
+ dict(zip(string.ascii_lowercase, [False]*len(string.ascii_lowercase)))
+ for label in string.ascii_lowercase}
+ if start_positions:
+ self.set_positions(*start_positions)
+ if not initial_signal:
+ initial_signal = self.test_start
+ self.pending = [initial_signal]
+ self.propagate(use_diagonal_board)
+ live_wire_count = len([self.banks[self.test_start.bank][w]
+ for w in self.banks[self.test_start.bank]
+ if self.banks[self.test_start.bank][w]])
+ if live_wire_count < 26:
+ if verify_plugboard:
+ possibles = self.possible_plugboards()
+ return all(s0.isdisjoint(s1) for s0 in possibles for s1 in possibles if s0 != s1)
+ else:
+ return True
+ else:
+ return False
+
+ def propagate(self, use_diagonal_board):
+ while self.pending:
+ current = self.pending[0]
+ # print("processing", current)
+ logger.debug("Propogater processing {}".format(current))
+ self.pending = self.pending[1:]
+ if not self.banks[current.bank][current.wire]:
+ self.banks[current.bank][current.wire] = True
+ if use_diagonal_board:
+ self.pending += [Signal(current.wire, current.bank)]
+ for c in self.connections:
+ if current.bank in c.banks:
+ other_bank = [b for b in c.banks if b != current.bank][0]
+ other_wire = c.scrambler.lookup(current.wire)
+ # print(" adding", other_bank, other_wire, "because", c.banks)
+ logger.debug("Propogator adding {0} {1} because {2}".format(other_bank, other_wire, c.banks))
+ self.pending += [Signal(other_bank, other_wire)]
+
+ def run(self, run_start=None, wheel1_pos='a', wheel2_pos='a', wheel3_pos='a', use_diagonal_board=True):
+ if not run_start:
+ run_start = self.test_start
+ self.solutions = []
+ self.set_positions(wheel1_pos, wheel2_pos, wheel3_pos)
+ for run_index in range(26*26*26):
+ if self.test(initial_signal=run_start, use_diagonal_board=use_diagonal_board):
+ self.solutions += [self.connections[0].scrambler.wheel_positions_l]
+ advance3 = True
+ advance2 = False
+ advance1 = False
+ if (run_index + 1) % 26 == 0: advance2 = True
+ if (run_index + 1) % (26*26) == 0: advance1 = True
+ for c in self.connections:
+ c.scrambler.advance(advance1, advance2, advance3)
+ return self.solutions
+
+ def possible_plugboards(self):
+ possibles = set()
+ for b in self.banks:
+ active = [w for w in self.banks[b] if self.banks[b][w]]
+ inactive = [w for w in self.banks[b] if not self.banks[b][w]]
+ if len(active) == 1:
+ possibles = possibles.union({frozenset((b, active[0]))})
+ if len(inactive) == 1:
+ possibles = possibles.union({frozenset((b, inactive[0]))})
+ return possibles
+
+
+def run_multi_bombe(wheel1_spec, wheel2_spec, wheel3_spec, reflector_spec, menu,
+ start_signal=None, use_diagonal_board=True,
+ verify_plugboard=True):
+ allwheels = itertools.product(string.ascii_lowercase, repeat=3)
+
+ with multiprocessing.Pool() as pool:
+ res = pool.map(Bombe(wheel1_spec, wheel2_spec, wheel3_spec,
+ reflector_spec, menu=menu, start_signal=start_signal,
+ use_diagonal_board=use_diagonal_board,
+ verify_plugboard=verify_plugboard),
+ allwheels)
+ return [r[0] for r in res if r[1]]
\ No newline at end of file
--- /dev/null
+from itertools import chain
+import multiprocessing
+from support.utilities import *
+from support.language_models import *
+from cipher.column_transposition import transpositions_of
+
+from logger import logger
+
+def make_cadenus_keycolumn(doubled_letters = 'vw', start='a', reverse=False):
+ """Makes the key column for a Cadenus cipher (the column down between the
+ rows of letters)
+
+ >>> make_cadenus_keycolumn()['a']
+ 0
+ >>> make_cadenus_keycolumn()['b']
+ 1
+ >>> make_cadenus_keycolumn()['c']
+ 2
+ >>> make_cadenus_keycolumn()['v']
+ 21
+ >>> make_cadenus_keycolumn()['w']
+ 21
+ >>> make_cadenus_keycolumn()['z']
+ 24
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['a']
+ 1
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['b']
+ 0
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['c']
+ 24
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['i']
+ 18
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['j']
+ 18
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['v']
+ 6
+ >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['z']
+ 2
+ """
+ index_to_remove = string.ascii_lowercase.find(doubled_letters[0])
+ short_alphabet = string.ascii_lowercase[:index_to_remove] + string.ascii_lowercase[index_to_remove+1:]
+ if reverse:
+ short_alphabet = cat(reversed(short_alphabet))
+ start_pos = short_alphabet.find(start)
+ rotated_alphabet = short_alphabet[start_pos:] + short_alphabet[:start_pos]
+ keycolumn = {l: i for i, l in enumerate(rotated_alphabet)}
+ keycolumn[doubled_letters[0]] = keycolumn[doubled_letters[1]]
+ return keycolumn
+
+def cadenus_encipher(message, keyword, keycolumn, fillvalue='a'):
+ """Encipher with the Cadenus cipher
+
+ >>> cadenus_encipher(sanitise('Whoever has made a voyage up the Hudson ' \
+ 'must remember the Kaatskill mountains. ' \
+ 'They are a dismembered branch of the great'), \
+ 'wink', \
+ make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True))
+ 'antodeleeeuhrsidrbhmhdrrhnimefmthgeaetakseomehetyaasuvoyegrastmmuuaeenabbtpchehtarorikswosmvaleatned'
+ >>> cadenus_encipher(sanitise('a severe limitation on the usefulness of ' \
+ 'the cadenus is that every message must be ' \
+ 'a multiple of twenty-five letters long'), \
+ 'easy', \
+ make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True))
+ 'systretomtattlusoatleeesfiyheasdfnmschbhneuvsnpmtofarenuseieeieltarlmentieetogevesitfaisltngeeuvowul'
+ """
+ rows = chunks(message, len(message) // 25, fillvalue=fillvalue)
+ columns = zip(*rows)
+ rotated_columns = [col[start:] + col[:start] for start, col in zip([keycolumn[l] for l in keyword], columns)]
+ rotated_rows = zip(*rotated_columns)
+ transpositions = transpositions_of(keyword)
+ transposed = [transpose(r, transpositions) for r in rotated_rows]
+ return cat(chain(*transposed))
+
+def cadenus_decipher(message, keyword, keycolumn, fillvalue='a'):
+ """
+ >>> cadenus_decipher('antodeleeeuhrsidrbhmhdrrhnimefmthgeaetakseomehetyaa' \
+ 'suvoyegrastmmuuaeenabbtpchehtarorikswosmvaleatned', \
+ 'wink', \
+ make_cadenus_keycolumn(reverse=True))
+ 'whoeverhasmadeavoyageupthehudsonmustrememberthekaatskillmountainstheyareadismemberedbranchofthegreat'
+ >>> cadenus_decipher('systretomtattlusoatleeesfiyheasdfnmschbhneuvsnpmtof' \
+ 'arenuseieeieltarlmentieetogevesitfaisltngeeuvowul', \
+ 'easy', \
+ make_cadenus_keycolumn(reverse=True))
+ 'aseverelimitationontheusefulnessofthecadenusisthateverymessagemustbeamultipleoftwentyfiveletterslong'
+ """
+ rows = chunks(message, len(message) // 25, fillvalue=fillvalue)
+ transpositions = transpositions_of(keyword)
+ untransposed_rows = [untranspose(r, transpositions) for r in rows]
+ columns = zip(*untransposed_rows)
+ rotated_columns = [col[-start:] + col[:-start] for start, col in zip([keycolumn[l] for l in keyword], columns)]
+ rotated_rows = zip(*rotated_columns)
+ # return rotated_columns
+ return cat(chain(*rotated_rows))
+
+
+def cadenus_break(message, words=keywords,
+ doubled_letters='vw', fitness=Pbigrams):
+ c = make_cadenus_keycolumn(reverse=True)
+ valid_words = [w for w in words
+ if max(transpositions_of(w)) <= len(c)]
+ with multiprocessing.Pool() as pool:
+ results = pool.starmap(cadenus_break_worker,
+ [(message, w,
+ make_cadenus_keycolumn(doubled_letters=doubled_letters,
+ start=s, reverse=r),
+ fitness)
+ for w in words
+ for s in string.ascii_lowercase
+ for r in [True, False]
+ if max(transpositions_of(w)) <= len(
+ make_cadenus_keycolumn(
+ doubled_letters=doubled_letters, start=s, reverse=r))
+ ])
+ # return list(results)
+ return max(results, key=lambda k: k[1])
+
+def cadenus_break_worker(message, keyword, keycolumn, fitness):
+ message_chunks = chunks(message, 175)
+ plaintext = ''.join(cadenus_decipher(c, keyword, keycolumn) for c in message_chunks)
+ fit = fitness(plaintext)
+ return (keyword, keycolumn), fit
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+from support.utilities import *
+from support.language_models import *
+
+from logger import logger
+
+def caesar_encipher_letter(accented_letter, shift):
+ """Encipher a letter, given a shift amount
+
+ >>> caesar_encipher_letter('a', 1)
+ 'b'
+ >>> caesar_encipher_letter('a', 2)
+ 'c'
+ >>> caesar_encipher_letter('b', 2)
+ 'd'
+ >>> caesar_encipher_letter('x', 2)
+ 'z'
+ >>> caesar_encipher_letter('y', 2)
+ 'a'
+ >>> caesar_encipher_letter('z', 2)
+ 'b'
+ >>> caesar_encipher_letter('z', -1)
+ 'y'
+ >>> caesar_encipher_letter('a', -1)
+ 'z'
+ >>> caesar_encipher_letter('A', 1)
+ 'B'
+ >>> caesar_encipher_letter('é', 1)
+ 'f'
+ """
+ # letter = unaccent(accented_letter)
+ # if letter in string.ascii_letters:
+ # if letter in string.ascii_uppercase:
+ # alphabet_start = ord('A')
+ # else:
+ # alphabet_start = ord('a')
+ # return chr(((ord(letter) - alphabet_start + shift) % 26) +
+ # alphabet_start)
+ # else:
+ # return letter
+
+ letter = unaccent(accented_letter)
+ if letter in string.ascii_letters:
+ cipherletter = unpos(pos(letter) + shift)
+ if letter in string.ascii_uppercase:
+ return cipherletter.upper()
+ else:
+ return cipherletter
+ else:
+ return letter
+
+def caesar_decipher_letter(letter, shift):
+ """Decipher a letter, given a shift amount
+
+ >>> caesar_decipher_letter('b', 1)
+ 'a'
+ >>> caesar_decipher_letter('b', 2)
+ 'z'
+ """
+ return caesar_encipher_letter(letter, -shift)
+
+def caesar_encipher(message, shift):
+ """Encipher a message with the Caesar cipher of given shift
+
+ >>> caesar_encipher('abc', 1)
+ 'bcd'
+ >>> caesar_encipher('abc', 2)
+ 'cde'
+ >>> caesar_encipher('abcxyz', 2)
+ 'cdezab'
+ >>> caesar_encipher('ab cx yz', 2)
+ 'cd ez ab'
+ >>> caesar_encipher('Héllo World!', 2)
+ 'Jgnnq Yqtnf!'
+ """
+ enciphered = [caesar_encipher_letter(l, shift) for l in message]
+ return cat(enciphered)
+
+def caesar_decipher(message, shift):
+ """Decipher a message with the Caesar cipher of given shift
+
+ >>> caesar_decipher('bcd', 1)
+ 'abc'
+ >>> caesar_decipher('cde', 2)
+ 'abc'
+ >>> caesar_decipher('cd ez ab', 2)
+ 'ab cx yz'
+ >>> caesar_decipher('Jgnnq Yqtnf!', 2)
+ 'Hello World!'
+ """
+ return caesar_encipher(message, -shift)
+
+
+def caesar_break(message, fitness=Pletters):
+ """Breaks a Caesar cipher using frequency analysis
+
+ >>> caesar_break('ibxcsyorsaqcheyklxivoexlevmrimwxsfiqevvmihrsasrxliwyrh' \
+ 'ecjsppsamrkwleppfmergefifvmhixscsymjcsyqeoixlm') # doctest: +ELLIPSIS
+ (4, -130.849989015...)
+ >>> caesar_break('wxwmaxdgheetgwuxztgptedbgznitgwwhpguxyhkxbmhvvtlbhgtee' \
+ 'raxlmhiixweblmxgxwmhmaxybkbgztgwztsxwbgmxgmert') # doctest: +ELLIPSIS
+ (19, -128.82410410...)
+ >>> caesar_break('yltbbqnqnzvguvaxurorgenafsbezqvagbnornfgsbevpnaabjurer' \
+ 'svaquvzyvxrnznazlybequrvfohgriraabjtbaruraprur') # doctest: +ELLIPSIS
+ (13, -126.25403935...)
+ """
+ sanitised_message = sanitise(message)
+ best_shift = 0
+ best_fit = float('-inf')
+ for shift in range(26):
+ plaintext = caesar_decipher(sanitised_message, shift)
+ fit = fitness(plaintext)
+ logger.debug('Caesar break attempt using key {0} gives fit of {1} '
+ 'and decrypt starting: {2}'.format(shift, fit,
+ plaintext[:50]))
+ if fit > best_fit:
+ best_fit = fit
+ best_shift = shift
+ logger.info('Caesar break best fit: key {0} gives fit of {1} and '
+ 'decrypt starting: {2}'.format(best_shift, best_fit,
+ caesar_decipher(sanitised_message, best_shift)[:50]))
+ return best_shift, best_fit
--- /dev/null
+import math
+import multiprocessing
+from itertools import chain
+from support.utilities import *
+from support.language_models import *
+
+from logger import logger
+
+def transpositions_of(keyword):
+ """Finds the transpostions given by a keyword. For instance, the keyword
+ 'clever' rearranges to 'celrv', so the first column (0) stays first, the
+ second column (1) moves to third, the third column (2) moves to second,
+ and so on.
+
+ If passed a tuple, assume it's already a transposition and just return it.
+
+ >>> transpositions_of('clever')
+ (0, 2, 1, 4, 3)
+ >>> transpositions_of('fred')
+ (3, 2, 0, 1)
+ >>> transpositions_of((3, 2, 0, 1))
+ (3, 2, 0, 1)
+ """
+ if isinstance(keyword, tuple):
+ return keyword
+ else:
+ key = deduplicate(keyword)
+ transpositions = tuple(key.index(l) for l in sorted(key))
+ return transpositions
+
+
+transpositions = collections.defaultdict(list)
+for word in keywords:
+ transpositions[transpositions_of(word)] += [word]
+
+
+def pad(message_len, group_len, fillvalue):
+ padding_length = group_len - message_len % group_len
+ if padding_length == group_len: padding_length = 0
+ padding = ''
+ for i in range(padding_length):
+ if callable(fillvalue):
+ padding += fillvalue()
+ else:
+ padding += fillvalue
+ return padding
+
+def column_transposition_encipher(message, keyword, fillvalue=' ',
+ fillcolumnwise=False,
+ emptycolumnwise=False):
+ """Enciphers using the column transposition cipher.
+ Message is padded to allow all rows to be the same length.
+
+ >>> column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True)
+ 'hlohr eltee '
+ >>> column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere '
+ >>> column_transposition_encipher('hellothere', 'abcdef')
+ 'hellothere '
+ >>> column_transposition_encipher('hellothere', 'abcde')
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=False)
+ 'hlohreltee'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=True)
+ 'htehlelroe'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=True)
+ 'heotllrehe'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=False)
+ 'holrhetlee'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=True)
+ 'htleehoelr'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=False)
+ 'hleolteher'
+ >>> column_transposition_encipher('hellothere', 'cleverly')
+ 'hleolthre e '
+ >>> column_transposition_encipher('hellothere', 'cleverly', fillvalue='!')
+ 'hleolthre!e!'
+ >>> column_transposition_encipher('hellothere', 'cleverly', fillvalue=lambda: '*')
+ 'hleolthre*e*'
+ """
+ transpositions = transpositions_of(keyword)
+ message += pad(len(message), len(transpositions), fillvalue)
+ if fillcolumnwise:
+ rows = every_nth(message, len(message) // len(transpositions))
+ else:
+ rows = chunks(message, len(transpositions))
+ transposed = [transpose(r, transpositions) for r in rows]
+ if emptycolumnwise:
+ return combine_every_nth(transposed)
+ else:
+ return cat(chain(*transposed))
+
+def column_transposition_decipher(message, keyword, fillvalue=' ',
+ fillcolumnwise=False,
+ emptycolumnwise=False):
+ """Deciphers using the column transposition cipher.
+ Message is padded to allow all rows to be the same length.
+
+ >>> column_transposition_decipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hlohreltee', 'abcde', fillcolumnwise=True, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('htehlelroe', 'abcde', fillcolumnwise=False, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('heotllrehe', 'clever', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('holrhetlee', 'clever', fillcolumnwise=True, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('htleehoelr', 'clever', fillcolumnwise=False, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hleolteher', 'clever', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ """
+ transpositions = transpositions_of(keyword)
+ message += pad(len(message), len(transpositions), fillvalue)
+ if emptycolumnwise:
+ rows = every_nth(message, len(message) // len(transpositions))
+ else:
+ rows = chunks(message, len(transpositions))
+ untransposed = [untranspose(r, transpositions) for r in rows]
+ if fillcolumnwise:
+ return combine_every_nth(untransposed)
+ else:
+ return cat(chain(*untransposed))
+
+def scytale_encipher(message, rows, fillvalue=' '):
+ """Enciphers using the scytale transposition cipher.
+ Message is padded with spaces to allow all rows to be the same length.
+
+ >>> scytale_encipher('thequickbrownfox', 3)
+ 'tcnhkfeboqrxuo iw '
+ >>> scytale_encipher('thequickbrownfox', 4)
+ 'tubnhirfecooqkwx'
+ >>> scytale_encipher('thequickbrownfox', 5)
+ 'tubn hirf ecoo qkwx '
+ >>> scytale_encipher('thequickbrownfox', 6)
+ 'tqcrnxhukof eibwo '
+ >>> scytale_encipher('thequickbrownfox', 7)
+ 'tqcrnx hukof eibwo '
+ """
+ # transpositions = [i for i in range(math.ceil(len(message) / rows))]
+ # return column_transposition_encipher(message, transpositions,
+ # fillvalue=fillvalue, fillcolumnwise=False, emptycolumnwise=True)
+ transpositions = [i for i in range(rows)]
+ return column_transposition_encipher(message, transpositions,
+ fillvalue=fillvalue, fillcolumnwise=True, emptycolumnwise=False)
+
+def scytale_decipher(message, rows):
+ """Deciphers using the scytale transposition cipher.
+ Assumes the message is padded so that all rows are the same length.
+
+ >>> scytale_decipher('tcnhkfeboqrxuo iw ', 3)
+ 'thequickbrownfox '
+ >>> scytale_decipher('tubnhirfecooqkwx', 4)
+ 'thequickbrownfox'
+ >>> scytale_decipher('tubn hirf ecoo qkwx ', 5)
+ 'thequickbrownfox '
+ >>> scytale_decipher('tqcrnxhukof eibwo ', 6)
+ 'thequickbrownfox '
+ >>> scytale_decipher('tqcrnx hukof eibwo ', 7)
+ 'thequickbrownfox '
+ """
+ # transpositions = [i for i in range(math.ceil(len(message) / rows))]
+ # return column_transposition_decipher(message, transpositions,
+ # fillcolumnwise=False, emptycolumnwise=True)
+ transpositions = [i for i in range(rows)]
+ return column_transposition_decipher(message, transpositions,
+ fillcolumnwise=True, emptycolumnwise=False)
+
+
+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...)
+ """
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, trans, fillcolumnwise, emptycolumnwise,
+ fitness)
+ for trans in translist
+ 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,
+ helper_args, chunksize)
+ return max(breaks, key=lambda k: k[1])
+column_transposition_break = column_transposition_break_mp
+
+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, fillcolumnwise, emptycolumnwise), fit
+
+
+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...)
+ """
+ with multiprocessing.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
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+
+# coding: utf-8
+
+##################################
+# # Enigma machine
+##################################
+# Specification from [Codes and Ciphers](http://www.codesandciphers.org.uk/enigma/rotorspec.htm) page.
+#
+# Example Enigma machines from [Louise Dale](http://enigma.louisedade.co.uk/enigma.html) (full simulation) and [EnigmaCo](http://enigmaco.de/enigma/enigma.html) (good animation of the wheels, but no ring settings).
+#
+# There's also the nice Enigma simulator for Android by [Franklin Heath](https://franklinheath.co.uk/2012/02/04/our-first-app-published-enigma-simulator/), available on the [Google Play store](https://play.google.com/store/apps/details?id=uk.co.franklinheath.enigmasim&hl=en_GB).
+
+
+
+import string
+import collections
+import multiprocessing
+import itertools
+import logging
+
+logger = logging.getLogger('engima')
+logger.setLevel(logging.WARNING)
+# logger.setLevel(logging.INFO)
+# logger.setLevel(logging.DEBUG)
+
+# create the logging file handler
+fh = logging.FileHandler("enigma.log")
+formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
+fh.setFormatter(formatter)
+
+# add handler to logger object
+logger.addHandler(fh)
+
+
+# Some convenience functions
+
+cat = ''.join
+
+def clean(text): return cat(l.lower() for l in text if l in string.ascii_letters)
+
+def pos(letter):
+ if letter in string.ascii_lowercase:
+ return ord(letter) - ord('a')
+ elif letter in string.ascii_uppercase:
+ return ord(letter) - ord('A')
+ else:
+ return ''
+
+def unpos(number): return chr(number % 26 + ord('a'))
+
+
+wheel_i_spec = 'ekmflgdqvzntowyhxuspaibrcj'
+wheel_ii_spec = 'ajdksiruxblhwtmcqgznpyfvoe'
+wheel_iii_spec = 'bdfhjlcprtxvznyeiwgakmusqo'
+wheel_iv_spec = 'esovpzjayquirhxlnftgkdcmwb'
+wheel_v_spec = 'vzbrgityupsdnhlxawmjqofeck'
+wheel_vi_spec = 'jpgvoumfyqbenhzrdkasxlictw'
+wheel_vii_spec = 'nzjhgrcxmyswboufaivlpekqdt'
+wheel_viii_spec = 'fkqhtlxocbjspdzramewniuygv'
+beta_wheel_spec = 'leyjvcnixwpbqmdrtakzgfuhos'
+gamma_wheel_spec = 'fsokanuerhmbtiycwlqpzxvgjd'
+
+wheel_i_notches = ['q']
+wheel_ii_notches = ['e']
+wheel_iii_notches = ['v']
+wheel_iv_notches = ['j']
+wheel_v_notches = ['z']
+wheel_vi_notches = ['z', 'm']
+wheel_vii_notches = ['z', 'm']
+wheel_viii_notches = ['z', 'm']
+
+reflector_b_spec = 'ay br cu dh eq fs gl ip jx kn mo tz vw'
+reflector_c_spec = 'af bv cp dj ei go hy kr lz mx nw tq su'
+
+
+
+class LetterTransformer(object):
+ """A generic substitution cipher, that has different transforms in the
+ forward and backward directions. It requires that the transforms for all
+ letters by provided.
+ """
+ def __init__(self, specification, raw_transform=False):
+ if raw_transform:
+ transform = specification
+ else:
+ transform = self.parse_specification(specification)
+ self.validate_transform(transform)
+ self.make_transform_map(transform)
+
+ def parse_specification(self, specification):
+ return list(zip(string.ascii_lowercase, clean(specification)))
+ # return specification
+
+ def validate_transform(self, transform):
+ """A set of pairs, of from-to"""
+ if len(transform) != 26:
+ raise ValueError("Transform specification has {} pairs, requires 26".
+ format(len(transform)))
+ for p in transform:
+ if len(p) != 2:
+ raise ValueError("Not all mappings in transform "
+ "have two elements")
+ if len(set([p[0] for p in transform])) != 26:
+ raise ValueError("Transform specification must list 26 origin letters")
+ if len(set([p[1] for p in transform])) != 26:
+ raise ValueError("Transform specification must list 26 destination letters")
+
+ def make_empty_transform(self):
+ self.forward_map = [0] * 26
+ self.backward_map = [0] * 26
+
+ def make_transform_map(self, transform):
+ self.make_empty_transform()
+ for p in transform:
+ self.forward_map[pos(p[0])] = pos(p[1])
+ self.backward_map[pos(p[1])] = pos(p[0])
+ return self.forward_map, self.backward_map
+
+ def forward(self, letter):
+ if letter in string.ascii_lowercase:
+ return unpos(self.forward_map[pos(letter)])
+ else:
+ return ''
+
+ def backward(self, letter):
+ if letter in string.ascii_lowercase:
+ return unpos(self.backward_map[pos(letter)])
+ else:
+ return ''
+
+
+class Plugboard(LetterTransformer):
+ """A plugboard, a type of letter transformer where forward and backward
+ transforms are the same. If a letter isn't explicitly transformed, it is
+ kept as it is.
+ """
+ def parse_specification(self, specification):
+ return [tuple(clean(p)) for p in specification.split()]
+
+ def validate_transform(self, transform):
+ """A set of pairs, of from-to"""
+ for p in transform:
+ if len(p) != 2:
+ raise ValueError("Not all mappings in transform"
+ "have two elements")
+
+ def make_empty_transform(self):
+ self.forward_map = list(range(26))
+ self.backward_map = list(range(26))
+
+ def make_transform_map(self, transform):
+ expanded_transform = transform + [tuple(reversed(p)) for p in transform]
+ return super(Plugboard, self).make_transform_map(expanded_transform)
+
+
+
+
+class Reflector(Plugboard):
+ """A reflector is a plugboard that requires 13 transforms.
+ """
+ def validate_transform(self, transform):
+ if len(transform) != 13:
+ raise ValueError("Reflector specification has {} pairs, requires 13".
+ format(len(transform)))
+ if len(set([p[0] for p in transform] +
+ [p[1] for p in transform])) != 26:
+ raise ValueError("Reflector specification does not contain 26 letters")
+ try:
+ super(Reflector, self).validate_transform(transform)
+ except ValueError as v:
+ raise ValueError("Not all mappings in reflector have two elements")
+
+
+
+
+class SimpleWheel(LetterTransformer):
+ """A wheel is a transform that rotates.
+
+ Looking from the right, letters go in sequence a-b-c clockwise around the
+ wheel.
+
+ The position of the wheel is the number of spaces anticlockwise the wheel
+ has turned.
+
+ Letter inputs and outputs are given relative to the frame holding the wheel,
+ so if the wheel is advanced three places, an input of 'p' will enter the
+ wheel on the position under the wheel's 'q' label.
+ """
+ def __init__(self, transform, position='a', raw_transform=False):
+ super(SimpleWheel, self).__init__(transform, raw_transform)
+ self.set_position(position)
+
+ def __getattribute__(self,name):
+ if name=='position_l':
+ return unpos(self.position)
+ else:
+ return object.__getattribute__(self, name)
+
+ def set_position(self, position):
+ if isinstance(position, str):
+ # self.position = ord(position) - ord('a')
+ self.position = pos(position)
+ else:
+ self.position = position
+
+ def forward(self, letter):
+ if letter in string.ascii_lowercase:
+ return unpos((self.forward_map[(pos(letter) + self.position) % 26] - self.position))
+ else:
+ return ''
+
+ def backward(self, letter):
+ if letter in string.ascii_lowercase:
+ return unpos((self.backward_map[(pos(letter) + self.position) % 26] - self.position))
+ else:
+ return ''
+
+ def advance(self):
+ self.position = (self.position + 1) % 26
+
+
+
+class Wheel(SimpleWheel):
+ """A wheel with a movable ring.
+
+ The ring holds the letters and the notches that turn other wheels. The core
+ holds the wiring that does the transformation.
+
+ The ring position is how many steps the core is turned relative to the ring.
+ This is one-based, so a ring setting of 1 means the core and ring are
+ aligned.
+
+ The position of the wheel is the position of the core (the transforms)
+ relative to the neutral position.
+
+ The position_l is the position of the ring, or what would be observed
+ by the user of the Enigma machine.
+
+ The notch_positions are the number of advances of this wheel before it will
+ advance the next wheel.
+
+ """
+ def __init__(self, transform, ring_notch_letters, ring_setting=1, position='a', raw_transform=False):
+ self.ring_notch_letters = ring_notch_letters
+ self.ring_setting = ring_setting
+ super(Wheel, self).__init__(transform, position=position, raw_transform=raw_transform)
+ self.set_position(position)
+
+ def __getattribute__(self,name):
+ if name=='position_l':
+ return unpos(self.position + self.ring_setting - 1)
+ else:
+ return object.__getattribute__(self, name)
+
+ def set_position(self, position):
+ if isinstance(position, str):
+ self.position = (pos(position) - self.ring_setting + 1) % 26
+ else:
+ self.position = (position - self.ring_setting) % 26
+ # # self.notch_positions = [(pos(p) - pos(position)) % 26 for p in self.ring_notch_letters]
+ # self.notch_positions = [(pos(p) - (self.position + self.ring_setting - 1)) % 26 for p in self.ring_notch_letters]
+ self.notch_positions = [(self.position + self.ring_setting - 1 - pos(p)) % 26 for p in self.ring_notch_letters]
+
+ def advance(self):
+ super(Wheel, self).advance()
+ self.notch_positions = [(p + 1) % 26 for p in self.notch_positions]
+ return self.position
+
+
+class Enigma(object):
+ """An Enigma machine.
+
+
+ """
+ def __init__(self, reflector_spec,
+ left_wheel_spec, left_wheel_notches,
+ middle_wheel_spec, middle_wheel_notches,
+ right_wheel_spec, right_wheel_notches,
+ left_ring_setting, middle_ring_setting, right_ring_setting,
+ plugboard_setting):
+ self.reflector = Reflector(reflector_spec)
+ self.left_wheel = Wheel(left_wheel_spec, left_wheel_notches, ring_setting=left_ring_setting)
+ self.middle_wheel = Wheel(middle_wheel_spec, middle_wheel_notches, ring_setting=middle_ring_setting)
+ self.right_wheel = Wheel(right_wheel_spec, right_wheel_notches, ring_setting=right_ring_setting)
+ self.plugboard = Plugboard(plugboard_setting)
+
+ def __getattribute__(self,name):
+ if name=='wheel_positions':
+ return self.left_wheel.position, self.middle_wheel.position, self.right_wheel.position
+ elif name=='wheel_positions_l':
+ return self.left_wheel.position_l, self.middle_wheel.position_l, self.right_wheel.position_l
+ elif name=='notch_positions':
+ return self.left_wheel.notch_positions, self.middle_wheel.notch_positions, self.right_wheel.notch_positions
+ else:
+ return object.__getattribute__(self, name)
+
+ def set_wheels(self, left_wheel_position, middle_wheel_position, right_wheel_position):
+ self.left_wheel.set_position(left_wheel_position)
+ self.middle_wheel.set_position(middle_wheel_position)
+ self.right_wheel.set_position(right_wheel_position)
+
+ def lookup(self, letter):
+ a = self.plugboard.forward(letter)
+ b = self.right_wheel.forward(a)
+ c = self.middle_wheel.forward(b)
+ d = self.left_wheel.forward(c)
+ e = self.reflector.forward(d)
+ f = self.left_wheel.backward(e)
+ g = self.middle_wheel.backward(f)
+ h = self.right_wheel.backward(g)
+ i = self.plugboard.backward(h)
+ return i
+
+ def advance(self):
+ advance_middle = False
+ advance_left = False
+ if 0 in self.right_wheel.notch_positions:
+ advance_middle = True
+ if 0 in self.middle_wheel.notch_positions:
+ advance_left = True
+ advance_middle = True
+ self.right_wheel.advance()
+ if advance_middle: self.middle_wheel.advance()
+ if advance_left: self.left_wheel.advance()
+
+ def encipher_letter(self, letter):
+ self.advance()
+ return self.lookup(letter)
+
+ def encipher(self, message):
+ enciphered = ''
+ for letter in clean(message):
+ enciphered += self.encipher_letter(letter)
+ return enciphered
+
+ decipher = encipher
+
+
+# for i in range(26):
+# enigma.advance()
+# print('enigma.advance()')
+# print("assert(enigma.wheel_positions == {})".format(enigma.wheel_positions))
+# print("assert(cat(enigma.wheel_positions_l) == '{}')".format(cat(enigma.wheel_positions_l)))
+# print("assert(enigma.notch_positions == {})".format(enigma.notch_positions))
+# print("assert(cat(enigma.lookup(l) for l in string.ascii_lowercase) == '{}')".format(cat(enigma.lookup(l) for l in string.ascii_lowercase)))
+# print()
+
+
+if __name__ == "__main__":
+ import doctest
+ # doctest.testmod(extraglobs={'lt': LetterTransformer(1, 'a')})
+ doctest.testmod()
+
--- /dev/null
+import multiprocessing
+import numpy as np
+from numpy import matrix
+from numpy import linalg
+from support.utilities import *
+from support.language_models import *
+from cipher.affine import modular_division_table
+
+from logger import logger
+
+
+def hill_encipher(matrix, message_letters, fillvalue='a'):
+ """Hill cipher
+
+ >>> hill_encipher(np.matrix([[7,8], [11,11]]), 'hellothere')
+ 'drjiqzdrvx'
+ >>> hill_encipher(np.matrix([[6, 24, 1], [13, 16, 10], [20, 17, 15]]), \
+ 'hello there')
+ 'tfjflpznvyac'
+ """
+ n = len(matrix)
+ sanitised_message = sanitise(message_letters)
+ if len(sanitised_message) % n != 0:
+ padding = fillvalue[0] * (n - len(sanitised_message) % n)
+ else:
+ padding = ''
+ message = [pos(c) for c in sanitised_message + padding]
+ message_chunks = [message[i:i+n] for i in range(0, len(message), n)]
+ # message_chunks = chunks(message, len(matrix), fillvalue=None)
+ enciphered_chunks = [((matrix * np.matrix(c).T).T).tolist()[0]
+ for c in message_chunks]
+ return cat([unpos(round(l))
+ for l in sum(enciphered_chunks, [])])
+
+def hill_decipher(matrix, message, fillvalue='a'):
+ """Hill cipher
+
+ >>> hill_decipher(np.matrix([[7,8], [11,11]]), 'drjiqzdrvx')
+ 'hellothere'
+ >>> hill_decipher(np.matrix([[6, 24, 1], [13, 16, 10], [20, 17, 15]]), \
+ 'tfjflpznvyac')
+ 'hellothereaa'
+ """
+ adjoint = linalg.det(matrix)*linalg.inv(matrix)
+ inverse_determinant = modular_division_table[int(round(linalg.det(matrix))) % 26, 1]
+ inverse_matrix = (inverse_determinant * adjoint) % 26
+ return hill_encipher(inverse_matrix, message, fillvalue)
+
+def hill_break(message, matrix_size=2, fitness=Pletters,
+ number_of_solutions=1, chunksize=500):
+
+ all_matrices = [np.matrix(list(m))
+ for m in itertools.product([list(r)
+ for r in itertools.product(range(26), repeat=matrix_size)],
+ repeat=matrix_size)]
+ valid_matrices = [m for m, d in
+ zip(all_matrices, (int(round(linalg.det(m))) for m in all_matrices))
+ if d != 0
+ if d % 2 != 0
+ if d % 13 != 0 ]
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, matrix, fitness)
+ for matrix in valid_matrices]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(hill_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 hill_break_worker(message, matrix, fitness):
+ plaintext = hill_decipher(matrix, message)
+ fit = fitness(plaintext)
+ logger.debug('Hill cipher break attempt using key {0} gives fit of '
+ '{1} and decrypt starting: {2}'.format(matrix,
+ fit, sanitise(plaintext)[:50]))
+ return matrix, fit
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+from enum import Enum
+# from itertools import starmap
+import multiprocessing
+import math
+from support.utilities import *
+from support.language_models import *
+
+from logger import logger
+import logging
+# logger.setLevel(logging.DEBUG)
+
+
+class KeywordWrapAlphabet(Enum):
+ from_a = 1
+ from_last = 2
+ from_largest = 3
+
+
+def keyword_cipher_alphabet_of(keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Find the cipher alphabet given a keyword.
+ wrap_alphabet controls how the rest of the alphabet is added
+ after the keyword.
+
+ >>> keyword_cipher_alphabet_of('bayes')
+ 'bayescdfghijklmnopqrtuvwxz'
+ >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_a)
+ 'bayescdfghijklmnopqrtuvwxz'
+ >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_last)
+ 'bayestuvwxzcdfghijklmnopqr'
+ >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_largest)
+ 'bayeszcdfghijklmnopqrtuvwx'
+ """
+ if wrap_alphabet == KeywordWrapAlphabet.from_a:
+ cipher_alphabet = cat(deduplicate(sanitise(keyword) +
+ string.ascii_lowercase))
+ else:
+ if wrap_alphabet == KeywordWrapAlphabet.from_last:
+ last_keyword_letter = deduplicate(sanitise(keyword))[-1]
+ else:
+ last_keyword_letter = sorted(sanitise(keyword))[-1]
+ last_keyword_position = string.ascii_lowercase.find(
+ last_keyword_letter) + 1
+ cipher_alphabet = cat(
+ deduplicate(sanitise(keyword) +
+ string.ascii_lowercase[last_keyword_position:] +
+ string.ascii_lowercase))
+ return cipher_alphabet
+
+
+def keyword_encipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Enciphers a message with a keyword substitution cipher.
+ wrap_alphabet controls how the rest of the alphabet is added
+ after the keyword.
+ 0 : from 'a'
+ 1 : from the last letter in the sanitised keyword
+ 2 : from the largest letter in the sanitised keyword
+
+ >>> keyword_encipher('test message', 'bayes')
+ 'rsqr ksqqbds'
+ >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_a)
+ 'rsqr ksqqbds'
+ >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_last)
+ 'lskl dskkbus'
+ >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_largest)
+ 'qspq jsppbcs'
+ """
+ cipher_alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet)
+ cipher_translation = ''.maketrans(string.ascii_lowercase, cipher_alphabet)
+ return unaccent(message).lower().translate(cipher_translation)
+
+def keyword_decipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Deciphers a message with a keyword substitution cipher.
+ wrap_alphabet controls how the rest of the alphabet is added
+ after the keyword.
+ 0 : from 'a'
+ 1 : from the last letter in the sanitised keyword
+ 2 : from the largest letter in the sanitised keyword
+
+ >>> keyword_decipher('rsqr ksqqbds', 'bayes')
+ 'test message'
+ >>> keyword_decipher('rsqr ksqqbds', 'bayes', KeywordWrapAlphabet.from_a)
+ 'test message'
+ >>> keyword_decipher('lskl dskkbus', 'bayes', KeywordWrapAlphabet.from_last)
+ 'test message'
+ >>> keyword_decipher('qspq jsppbcs', 'bayes', KeywordWrapAlphabet.from_largest)
+ 'test message'
+ """
+ cipher_alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet)
+ cipher_translation = ''.maketrans(cipher_alphabet, string.ascii_lowercase)
+ return message.lower().translate(cipher_translation)
+
+
+def keyword_break(message, wordlist=keywords, fitness=Pletters):
+ """Breaks a keyword substitution cipher using a dictionary and
+ frequency analysis.
+
+ >>> keyword_break(keyword_encipher('this is a test message for the ' \
+ 'keyword decipherment', 'elephant', KeywordWrapAlphabet.from_last), \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
+ (('elephant', <KeywordWrapAlphabet.from_last: 2>), -52.834575011...)
+ """
+ best_keyword = ''
+ best_wrap_alphabet = True
+ best_fit = float("-inf")
+ for wrap_alphabet in KeywordWrapAlphabet:
+ for keyword in wordlist:
+ plaintext = keyword_decipher(message, keyword, wrap_alphabet)
+ 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]))
+ if fit > best_fit:
+ best_fit = fit
+ best_keyword = keyword
+ best_wrap_alphabet = wrap_alphabet
+ logger.info('Keyword break best fit with key {0} (wrap={1}) gives fit of '
+ '{2} and decrypt starting: {3}'.format(best_keyword,
+ best_wrap_alphabet, best_fit, sanitise(
+ keyword_decipher(message, best_keyword,
+ best_wrap_alphabet))[:50]))
+ return (best_keyword, best_wrap_alphabet), best_fit
+
+def keyword_break_mp(message, wordlist=keywords, fitness=Pletters,
+ number_of_solutions=1, chunksize=500):
+ """Breaks a keyword substitution cipher using a dictionary and
+ frequency analysis
+
+ >>> keyword_break_mp(keyword_encipher('this is a test message for the ' \
+ 'keyword decipherment', 'elephant', KeywordWrapAlphabet.from_last), \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
+ (('elephant', <KeywordWrapAlphabet.from_last: 2>), -52.834575011...)
+ >>> keyword_break_mp(keyword_encipher('this is a test message for the ' \
+ 'keyword decipherment', 'elephant', KeywordWrapAlphabet.from_last), \
+ wordlist=['cat', 'elephant', 'kangaroo'], \
+ number_of_solutions=2) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ [(('elephant', <KeywordWrapAlphabet.from_last: 2>), -52.834575011...),
+ (('elephant', <KeywordWrapAlphabet.from_largest: 3>), -52.834575011...)]
+ """
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, word, wrap, fitness)
+ for word in wordlist
+ for wrap in KeywordWrapAlphabet]
+ # 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)
+ 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 keyword_break_worker(message, keyword, wrap_alphabet, fitness):
+ plaintext = keyword_decipher(message, keyword, wrap_alphabet)
+ 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), fit
+
+
+def monoalphabetic_break_hillclimbing(message,
+ max_iterations=20000,
+ plain_alphabet=None,
+ cipher_alphabet=None,
+ swap_index_finder=None,
+ fitness=Pletters, chunksize=1):
+ return simulated_annealing_break(message,
+ workers=1,
+ initial_temperature=0,
+ max_iterations=max_iterations,
+ plain_alphabet=plain_alphabet,
+ cipher_alphabet=cipher_alphabet,
+ swap_index_finder=swap_index_finder,
+ fitness=fitness, chunksize=chunksize)
+
+
+def monoalphabetic_break_hillclimbing_mp(message,
+ workers=10,
+ max_iterations=20000,
+ plain_alphabet=None,
+ cipher_alphabet=None,
+ swap_index_finder=None,
+ fitness=Pletters, chunksize=1):
+ return simulated_annealing_break(message,
+ workers=workers,
+ initial_temperature=0,
+ max_iterations=max_iterations,
+ plain_alphabet=plain_alphabet,
+ cipher_alphabet=cipher_alphabet,
+ swap_index_finder=swap_index_finder,
+ fitness=fitness, chunksize=chunksize)
+
+
+def gaussian_swap_index(a):
+ return (a + int(random.gauss(0, 4))) % 26
+
+def uniform_swap_index(a):
+ return random.randrange(26)
+
+def simulated_annealing_break(message, workers=10,
+ initial_temperature=200,
+ max_iterations=20000,
+ plain_alphabet=None,
+ cipher_alphabet=None,
+ swap_index_finder=None,
+ fitness=Ptrigrams, chunksize=1):
+ worker_args = []
+ ciphertext = sanitise(message)
+ if swap_index_finder is None:
+ swap_index_finder = gaussian_swap_index
+
+ for i in range(workers):
+ if plain_alphabet is None:
+ used_plain_alphabet = string.ascii_lowercase
+ else:
+ used_plain_alphabet = plain_alphabet
+ if cipher_alphabet is None:
+ used_cipher_alphabet = list(string.ascii_lowercase)
+ random.shuffle(used_cipher_alphabet)
+ used_cipher_alphabet = cat(used_cipher_alphabet)
+ else:
+ used_cipher_alphabet = cipher_alphabet
+ # if not plain_alphabet:
+ # plain_alphabet = string.ascii_lowercase
+ # if not cipher_alphabet:
+ # cipher_alphabet = list(string.ascii_lowercase)
+ # random.shuffle(cipher_alphabet)
+ # cipher_alphabet = cat(cipher_alphabet)
+ worker_args.append((ciphertext, used_plain_alphabet, used_cipher_alphabet,
+ swap_index_finder,
+ initial_temperature, max_iterations, fitness,
+ i))
+ with multiprocessing.Pool() as pool:
+ breaks = pool.starmap(simulated_annealing_break_worker,
+ worker_args, chunksize)
+ return max(breaks, key=lambda k: k[1])
+
+
+def simulated_annealing_break_worker(message, plain_alphabet, cipher_alphabet,
+ swap_index_finder,
+ t0, max_iterations, fitness,
+ logID):
+ 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:])
+
+ temperature = t0
+
+ dt = t0 / (0.9 * max_iterations)
+
+ current_alphabet = cipher_alphabet
+ alphabet = current_alphabet
+ cipher_translation = ''.maketrans(current_alphabet, plain_alphabet)
+ plaintext = message.translate(cipher_translation)
+ current_fitness = fitness(plaintext)
+
+ best_alphabet = current_alphabet
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+
+ # print('starting for', max_iterations)
+ for i in range(max_iterations):
+ swap_a = random.randrange(26)
+ # swap_b = (swap_a + int(random.gauss(0, 4))) % 26
+ swap_b = swap_index_finder(swap_a)
+ alphabet = swap(current_alphabet, swap_a, swap_b)
+ cipher_translation = ''.maketrans(alphabet, plain_alphabet)
+ plaintext = message.translate(cipher_translation)
+ new_fitness = fitness(plaintext)
+ try:
+ sa_chance = math.exp((new_fitness - current_fitness) / temperature)
+ except (OverflowError, ZeroDivisionError):
+ # print('exception triggered: new_fit {}, current_fit {}, temp {}'.format(new_fitness, current_fitness, temperature))
+ sa_chance = 0
+ if (new_fitness > current_fitness or random.random() < sa_chance):
+ # logger.debug('Simulated annealing: iteration {}, temperature {}, '
+ # 'current alphabet {}, current_fitness {}, '
+ # 'best_plaintext {}'.format(i, temperature, current_alphabet,
+ # current_fitness, best_plaintext[:50]))
+
+ # logger.debug('new_fit {}, current_fit {}, temp {}, sa_chance {}'.format(new_fitness, current_fitness, temperature, sa_chance))
+ current_fitness = new_fitness
+ current_alphabet = alphabet
+
+ if current_fitness > best_fitness:
+ best_alphabet = current_alphabet
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+ if i % 500 == 0:
+ logger.debug('Simulated annealing worker {}: iteration {}, temperature {}, '
+ 'current alphabet {}, plain alphabet {}, current_fitness {}, '
+ 'best_plaintext {}'.format(logID, i, temperature, current_alphabet, plain_alphabet,
+ current_fitness, plaintext[:50]))
+ temperature = max(temperature - dt, 0.001)
+
+ return best_alphabet, best_fitness # current_alphabet, current_fitness
+
+if __name__ == "__main__":
+ import doctest
--- /dev/null
+from support.utilities import *
+from support.language_models import *
+from cipher.keyword_cipher import KeywordWrapAlphabet, keyword_cipher_alphabet_of
+from cipher.polybius import polybius_grid
+import multiprocessing
+
+from logger import logger
+
+def playfair_wrap(n, lowest, highest):
+ skip = highest - lowest + 1
+ while n > highest or n < lowest:
+ if n > highest:
+ n -= skip
+ if n < lowest:
+ n += skip
+ return n
+
+def playfair_encipher_bigram(ab, grid, padding_letter='x'):
+ a, b = ab
+ max_row = max(c[0] for c in grid.values())
+ max_col = max(c[1] for c in grid.values())
+ min_row = min(c[0] for c in grid.values())
+ min_col = min(c[1] for c in grid.values())
+ if a == b:
+ b = padding_letter
+ if grid[a][0] == grid[b][0]: # same row
+ cp = (grid[a][0], playfair_wrap(grid[a][1] + 1, min_col, max_col))
+ dp = (grid[b][0], playfair_wrap(grid[b][1] + 1, min_col, max_col))
+ elif grid[a][1] == grid[b][1]: # same column
+ cp = (playfair_wrap(grid[a][0] + 1, min_row, max_row), grid[a][1])
+ dp = (playfair_wrap(grid[b][0] + 1, min_row, max_row), grid[b][1])
+ else:
+ cp = (grid[a][0], grid[b][1])
+ dp = (grid[b][0], grid[a][1])
+ c = [k for k, v in grid.items() if v == cp][0]
+ d = [k for k, v in grid.items() if v == dp][0]
+ return c + d
+
+def playfair_decipher_bigram(ab, grid, padding_letter='x'):
+ a, b = ab
+ max_row = max(c[0] for c in grid.values())
+ max_col = max(c[1] for c in grid.values())
+ min_row = min(c[0] for c in grid.values())
+ min_col = min(c[1] for c in grid.values())
+ if a == b:
+ b = padding_letter
+ if grid[a][0] == grid[b][0]: # same row
+ cp = (grid[a][0], playfair_wrap(grid[a][1] - 1, min_col, max_col))
+ dp = (grid[b][0], playfair_wrap(grid[b][1] - 1, min_col, max_col))
+ elif grid[a][1] == grid[b][1]: # same column
+ cp = (playfair_wrap(grid[a][0] - 1, min_row, max_row), grid[a][1])
+ dp = (playfair_wrap(grid[b][0] - 1, min_row, max_row), grid[b][1])
+ else:
+ cp = (grid[a][0], grid[b][1])
+ dp = (grid[b][0], grid[a][1])
+ c = [k for k, v in grid.items() if v == cp][0]
+ d = [k for k, v in grid.items() if v == dp][0]
+ return c + d
+
+def playfair_bigrams(text, padding_letter='x', padding_replaces_repeat=True):
+ i = 0
+ bigrams = []
+ while i < len(text):
+ bigram = text[i:i+2]
+ if len(bigram) == 1:
+ i = len(text) + 1
+ bigram = bigram + padding_letter
+ else:
+ if bigram[0] == bigram[1]:
+ bigram = bigram[0] + padding_letter
+ if padding_replaces_repeat:
+ i += 2
+ else:
+ i += 1
+ else:
+ i += 2
+ bigrams += [bigram]
+ return bigrams
+
+def playfair_encipher(message, keyword, padding_letter='x',
+ padding_replaces_repeat=False, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ column_order = list(range(5))
+ row_order = list(range(5))
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = polybius_grid(keyword, column_order, row_order,
+ letters_to_merge=letters_to_merge,
+ wrap_alphabet=wrap_alphabet)
+ message_bigrams = playfair_bigrams(sanitise(message), padding_letter=padding_letter,
+ padding_replaces_repeat=padding_replaces_repeat)
+ ciphertext_bigrams = [playfair_encipher_bigram(b, grid, padding_letter=padding_letter) for b in message_bigrams]
+ return cat(ciphertext_bigrams)
+
+def playfair_decipher(message, keyword, padding_letter='x',
+ padding_replaces_repeat=False, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ column_order = list(range(5))
+ row_order = list(range(5))
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = polybius_grid(keyword, column_order, row_order,
+ letters_to_merge=letters_to_merge,
+ wrap_alphabet=wrap_alphabet)
+ message_bigrams = playfair_bigrams(sanitise(message), padding_letter=padding_letter,
+ padding_replaces_repeat=padding_replaces_repeat)
+ plaintext_bigrams = [playfair_decipher_bigram(b, grid, padding_letter=padding_letter) for b in message_bigrams]
+ return cat(plaintext_bigrams)
+
+def playfair_break_mp(message,
+ letters_to_merge=None, padding_letter='x',
+ wordlist=keywords, fitness=Pletters,
+ number_of_solutions=1, chunksize=500):
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, word, wrap,
+ letters_to_merge, padding_letter,
+ pad_replace,
+ fitness)
+ for word in wordlist
+ for wrap in KeywordWrapAlphabet
+ for pad_replace in [False, True]]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(playfair_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 playfair_break_worker(message, keyword, wrap,
+ letters_to_merge, padding_letter,
+ pad_replace,
+ fitness):
+ plaintext = playfair_decipher(message, keyword, padding_letter,
+ pad_replace,
+ letters_to_merge,
+ wrap)
+ if plaintext:
+ fit = fitness(plaintext)
+ else:
+ fit = float('-inf')
+ logger.debug('Playfair break attempt using key {0} (wrap={1}, merging {2}, '
+ 'pad replaces={3}), '
+ 'gives fit of {4} and decrypt starting: '
+ '{5}'.format(keyword, wrap, letters_to_merge, pad_replace,
+ fit, sanitise(plaintext)[:50]))
+ return (keyword, wrap, letters_to_merge, padding_letter, pad_replace), fit
+
+def playfair_simulated_annealing_break(message, workers=10,
+ initial_temperature=200,
+ max_iterations=20000,
+ plain_alphabet=None,
+ cipher_alphabet=None,
+ fitness=Pletters, chunksize=1):
+ worker_args = []
+ ciphertext = sanitise(message)
+ for i in range(workers):
+ if plain_alphabet is None:
+ used_plain_alphabet = string.ascii_lowercase
+ else:
+ used_plain_alphabet = plain_alphabet
+ if cipher_alphabet is None:
+ # used_cipher_alphabet = list(string.ascii_lowercase)
+ # random.shuffle(used_cipher_alphabet)
+ # used_cipher_alphabet = cat(used_cipher_alphabet)
+ used_cipher_alphabet = random.choice(keywords)
+ else:
+ used_cipher_alphabet = cipher_alphabet
+ worker_args.append((ciphertext, used_plain_alphabet, used_cipher_alphabet,
+ initial_temperature, max_iterations, fitness))
+ with multiprocessing.Pool() as pool:
+ breaks = pool.starmap(playfair_simulated_annealing_break_worker,
+ worker_args, chunksize)
+ return max(breaks, key=lambda k: k[1])
+
+def playfair_simulated_annealing_break_worker(message, plain_alphabet, cipher_alphabet,
+ t0, 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:])
+
+ temperature = t0
+
+ dt = t0 / (0.9 * max_iterations)
+
+ current_alphabet = cipher_alphabet
+ current_wrap = KeywordWrapAlphabet.from_a
+ current_letters_to_merge = {'j': 'i'}
+ current_pad_replace = False
+ current_padding_letter = 'x'
+
+ alphabet = current_alphabet
+ wrap = current_wrap
+ letters_to_merge = current_letters_to_merge
+ pad_replace = current_pad_replace
+ padding_letter = current_padding_letter
+ plaintext = playfair_decipher(message, alphabet, padding_letter,
+ pad_replace,
+ letters_to_merge,
+ wrap)
+ current_fitness = fitness(plaintext)
+
+ best_alphabet = current_alphabet
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+
+ # print('starting for', max_iterations)
+ for i in range(max_iterations):
+ chosen = random.random()
+ # if chosen < 0.7:
+ # swap_a = random.randrange(26)
+ # swap_b = (swap_a + int(random.gauss(0, 4))) % 26
+ # alphabet = swap(current_alphabet, swap_a, swap_b)
+ # elif chosen < 0.8:
+ # wrap = random.choice(list(KeywordWrapAlphabet))
+ # elif chosen < 0.9:
+ # pad_replace = random.choice([True, False])
+ # elif chosen < 0.95:
+ # letter_from = random.choice(string.ascii_lowercase)
+ # letter_to = random.choice([c for c in string.ascii_lowercase if c != letter_from])
+ # letters_to_merge = {letter_from: letter_to}
+ # else:
+ # padding_letter = random.choice(string.ascii_lowercase)
+ if chosen < 0.7:
+ swap_a = random.randrange(len(current_alphabet))
+ swap_b = (swap_a + int(random.gauss(0, 4))) % len(current_alphabet)
+ alphabet = swap(current_alphabet, swap_a, swap_b)
+ elif chosen < 0.85:
+ new_letter = random.choice(string.ascii_lowercase)
+ alphabet = swap(current_alphabet + new_letter, random.randrange(len(current_alphabet)), len(current_alphabet))
+ else:
+ if len(current_alphabet) > 1:
+ deletion_position = random.randrange(len(current_alphabet))
+ alphabet = current_alphabet[:deletion_position] + current_alphabet[deletion_position+1:]
+ else:
+ alphabet = current_alphabet
+
+ try:
+ plaintext = playfair_decipher(message, alphabet, padding_letter,
+ pad_replace,
+ letters_to_merge,
+ wrap)
+ except:
+ print("Error", alphabet, padding_letter,
+ pad_replace,
+ letters_to_merge,
+ wrap)
+ raise
+
+ new_fitness = fitness(plaintext)
+ try:
+ sa_chance = math.exp((new_fitness - current_fitness) / temperature)
+ except (OverflowError, ZeroDivisionError):
+ # print('exception triggered: new_fit {}, current_fit {}, temp {}'.format(new_fitness, current_fitness, temperature))
+ sa_chance = 0
+ if (new_fitness > current_fitness or random.random() < sa_chance):
+ # logger.debug('Simulated annealing: iteration {}, temperature {}, '
+ # 'current alphabet {}, current_fitness {}, '
+ # 'best_plaintext {}'.format(i, temperature, current_alphabet,
+ # current_fitness, best_plaintext[:50]))
+
+ # logger.debug('new_fit {}, current_fit {}, temp {}, sa_chance {}'.format(new_fitness, current_fitness, temperature, sa_chance))
+ current_fitness = new_fitness
+ current_alphabet = alphabet
+ current_wrap = wrap
+ current_letters_to_merge = letters_to_merge
+ current_pad_replace = pad_replace
+ current_padding_letter = padding_letter
+
+ if current_fitness > best_fitness:
+ best_alphabet = current_alphabet
+ best_wrap = current_wrap
+ best_letters_to_merge = current_letters_to_merge
+ best_pad_replace = current_pad_replace
+ best_padding_letter = current_padding_letter
+ best_fitness = current_fitness
+ best_plaintext = plaintext
+ if i % 500 == 0:
+ logger.debug('Simulated annealing: iteration {}, temperature {}, '
+ 'current alphabet {}, current_fitness {}, '
+ 'best_plaintext {}'.format(i, temperature, current_alphabet,
+ current_fitness, plaintext[:50]))
+ temperature = max(temperature - dt, 0.001)
+
+ return { 'alphabet': best_alphabet
+ , 'wrap': best_wrap
+ , 'letters_to_merge': best_letters_to_merge
+ , 'pad_replace': best_pad_replace
+ , 'padding_letter': best_padding_letter
+ }, best_fitness # current_alphabet, current_fitness
--- /dev/null
+from support.utilities import *
+from support.language_models import *
+
+from logger import logger
+
+
+class PocketEnigma(object):
+ """A pocket enigma machine
+ The wheel is internally represented as a 26-element list self.wheel_map,
+ where wheel_map[i] == j shows that the position i places on from the arrow
+ maps to the position j places on.
+ """
+ def __init__(self, wheel=1, position='a'):
+ """initialise the pocket enigma, including which wheel to use and the
+ starting position of the wheel.
+
+ The wheel is either 1 or 2 (the predefined wheels) or a list of letter
+ pairs.
+
+ The position is the letter pointed to by the arrow on the wheel.
+
+ >>> pe.wheel_map
+ [25, 4, 23, 10, 1, 7, 9, 5, 12, 6, 3, 17, 8, 14, 13, 21, 19, 11, 20, 16, 18, 15, 24, 2, 22, 0]
+ >>> pe.position
+ 0
+ """
+ self.wheel1 = [('a', 'z'), ('b', 'e'), ('c', 'x'), ('d', 'k'),
+ ('f', 'h'), ('g', 'j'), ('i', 'm'), ('l', 'r'), ('n', 'o'),
+ ('p', 'v'), ('q', 't'), ('s', 'u'), ('w', 'y')]
+ self.wheel2 = [('a', 'c'), ('b', 'd'), ('e', 'w'), ('f', 'i'),
+ ('g', 'p'), ('h', 'm'), ('j', 'k'), ('l', 'n'), ('o', 'q'),
+ ('r', 'z'), ('s', 'u'), ('t', 'v'), ('x', 'y')]
+ if wheel == 1:
+ self.make_wheel_map(self.wheel1)
+ elif wheel == 2:
+ self.make_wheel_map(self.wheel2)
+ else:
+ self.validate_wheel_spec(wheel)
+ self.make_wheel_map(wheel)
+ if position in string.ascii_lowercase:
+ self.position = pos(position)
+ else:
+ self.position = position
+
+ def make_wheel_map(self, wheel_spec):
+ """Expands a wheel specification from a list of letter-letter pairs
+ into a full wheel_map.
+
+ >>> pe.make_wheel_map(pe.wheel2)
+ [2, 3, 0, 1, 22, 8, 15, 12, 5, 10, 9, 13, 7, 11, 16, 6, 14, 25, 20, 21, 18, 19, 4, 24, 23, 17]
+ """
+ self.validate_wheel_spec(wheel_spec)
+ self.wheel_map = [0] * 26
+ for p in wheel_spec:
+ self.wheel_map[pos(p[0])] = pos(p[1])
+ self.wheel_map[pos(p[1])] = pos(p[0])
+ return self.wheel_map
+
+ def validate_wheel_spec(self, wheel_spec):
+ """Validates that a wheel specificaiton will turn into a valid wheel
+ map.
+
+ >>> pe.validate_wheel_spec([])
+ Traceback (most recent call last):
+ ...
+ ValueError: Wheel specification has 0 pairs, requires 13
+ >>> pe.validate_wheel_spec([('a', 'b', 'c')]*13)
+ Traceback (most recent call last):
+ ...
+ ValueError: Not all mappings in wheel specificationhave two elements
+ >>> pe.validate_wheel_spec([('a', 'b')]*13)
+ Traceback (most recent call last):
+ ...
+ ValueError: Wheel specification does not contain 26 letters
+ """
+ if len(wheel_spec) != 13:
+ raise ValueError("Wheel specification has {} pairs, requires 13".
+ format(len(wheel_spec)))
+ for p in wheel_spec:
+ if len(p) != 2:
+ raise ValueError("Not all mappings in wheel specification"
+ "have two elements")
+ if len(set([p[0] for p in wheel_spec] +
+ [p[1] for p in wheel_spec])) != 26:
+ raise ValueError("Wheel specification does not contain 26 letters")
+
+ def encipher_letter(self, letter):
+ """Enciphers a single letter, by advancing the wheel before looking up
+ the letter on the wheel.
+
+ >>> pe.set_position('f')
+ 5
+ >>> pe.encipher_letter('k')
+ 'h'
+ """
+ self.advance()
+ return self.lookup(letter)
+ decipher_letter = encipher_letter
+
+ def lookup(self, letter):
+ """Look up what a letter enciphers to, without turning the wheel.
+
+ >>> pe.set_position('f')
+ 5
+ >>> cat([pe.lookup(l) for l in string.ascii_lowercase])
+ 'udhbfejcpgmokrliwntsayqzvx'
+ >>> pe.lookup('A')
+ ''
+ """
+ if letter in string.ascii_lowercase:
+ return unpos(
+ (self.wheel_map[(pos(letter) - self.position) % 26] +
+ self.position))
+ else:
+ return ''
+
+ def advance(self):
+ """Advances the wheel one position.
+
+ >>> pe.set_position('f')
+ 5
+ >>> pe.advance()
+ 6
+ """
+ self.position = (self.position + 1) % 26
+ return self.position
+
+ def encipher(self, message, starting_position=None):
+ """Enciphers a whole message.
+
+ >>> pe.set_position('f')
+ 5
+ >>> pe.encipher('helloworld')
+ 'kjsglcjoqc'
+ >>> pe.set_position('f')
+ 5
+ >>> pe.encipher('kjsglcjoqc')
+ 'helloworld'
+ >>> pe.encipher('helloworld', starting_position = 'x')
+ 'egrekthnnf'
+ """
+ if starting_position:
+ self.set_position(starting_position)
+ transformed = ''
+ for l in message:
+ transformed += self.encipher_letter(l)
+ return transformed
+ decipher = encipher
+
+ def set_position(self, position):
+ """Sets the position of the wheel, by specifying the letter the arrow
+ points to.
+
+ >>> pe.set_position('a')
+ 0
+ >>> pe.set_position('m')
+ 12
+ >>> pe.set_position('z')
+ 25
+ """
+ self.position = pos(position)
+ return self.position
+
+
+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
+
+if __name__ == "__main__":
+ import doctest
+ doctest.testmod(extraglobs={'pe': PocketEnigma(1, 'a')})
\ No newline at end of file
--- /dev/null
+import multiprocessing
+from support.utilities import *
+from support.language_models import *
+from cipher.keyword_cipher import KeywordWrapAlphabet, keyword_cipher_alphabet_of
+
+from logger import logger
+
+def polybius_grid(keyword, column_order, row_order, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Grid for a Polybius cipher, using a keyword to rearrange the
+ alphabet.
+
+
+ >>> polybius_grid('a', 'abcde', 'abcde')['x'] == ('e', 'c')
+ True
+ >>> polybius_grid('elephant', 'abcde', 'abcde')['e'] == ('a', 'a')
+ True
+ >>> polybius_grid('elephant', 'abcde', 'abcde')['b'] == ('b', 'c')
+ True
+ """
+ alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet=wrap_alphabet)
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = {l: k
+ for k, l in zip([(c, r) for c in column_order for r in row_order],
+ [l for l in alphabet if l not in letters_to_merge])}
+ for l in letters_to_merge:
+ grid[l] = grid[letters_to_merge[l]]
+ return grid
+
+def polybius_reverse_grid(keyword, column_order, row_order, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Grid for decrypting using a Polybius cipher, using a keyword to
+ rearrange the alphabet.
+
+ >>> polybius_reverse_grid('a', 'abcde', 'abcde')['e', 'c'] == 'x'
+ True
+ >>> polybius_reverse_grid('elephant', 'abcde', 'abcde')['a', 'a'] == 'e'
+ True
+ >>> polybius_reverse_grid('elephant', 'abcde', 'abcde')['b', 'c'] == 'b'
+ True
+ """
+ alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet=wrap_alphabet)
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = {k: l
+ for k, l in zip([(c, r) for c in column_order for r in row_order],
+ [l for l in alphabet if l not in letters_to_merge])}
+ return grid
+
+
+def polybius_flatten(pair, column_first):
+ """Convert a series of pairs into a single list of characters"""
+ if column_first:
+ return str(pair[1]) + str(pair[0])
+ else:
+ return str(pair[0]) + str(pair[1])
+
+def polybius_encipher(message, keyword, column_order, row_order,
+ column_first=False,
+ letters_to_merge=None, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Encipher a message with Polybius cipher, using a keyword to rearrange
+ the alphabet
+
+
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', \
+ [1, 2, 3, 4, 5], [1, 2, 3, 4, 5], \
+ wrap_alphabet=KeywordWrapAlphabet.from_last)
+ '2214445544551522115522511155551543114252542214111352123234442355411135441314115451112122'
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', \
+ column_first=False)
+ 'bbadccddccddaebbaaddbbceaaddddaecbaacadadcbbadaaacdaabedbcccdeddbeaabdccacadaadcceaababb'
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', \
+ column_first=True)
+ 'bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaacaadbadecbccedddebaadbcccadaaacdecaaabbb'
+ """
+ grid = polybius_grid(keyword, column_order, row_order, letters_to_merge, wrap_alphabet)
+ return cat(polybius_flatten(grid[l], column_first)
+ for l in message
+ if l in grid)
+
+
+def polybius_decipher(message, keyword, column_order, row_order,
+ column_first=False,
+ letters_to_merge=None, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Decipher a message with a Polybius cipher, using a keyword to rearrange
+ the alphabet
+
+ >>> polybius_decipher('bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaaca'\
+ 'adbadecbccedddebaadbcccadaaacdecaaabbb', 'elephant', 'abcde', 'abcde', \
+ column_first=False)
+ 'toisisvtestxessvbephktoefhnugiysweqifoekxelt'
+
+ >>> polybius_decipher('bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaaca'\
+ 'adbadecbccedddebaadbcccadaaacdecaaabbb', 'elephant', 'abcde', 'abcde', \
+ column_first=True)
+ 'thisisatestmessageforthepolybiusdecipherment'
+ """
+ grid = polybius_reverse_grid(keyword, column_order, row_order, letters_to_merge, wrap_alphabet)
+ column_index_type = type(column_order[0])
+ row_index_type = type(row_order[0])
+ if column_first:
+ pairs = [(column_index_type(p[1]), row_index_type(p[0])) for p in chunks(message, 2)]
+ else:
+ pairs = [(row_index_type(p[0]), column_index_type(p[1])) for p in chunks(message, 2)]
+ return cat(grid[p] for p in pairs if p in grid)
+
+
+def polybius_break_mp(message, column_labels, row_labels,
+ letters_to_merge=None,
+ wordlist=keywords, fitness=Pletters,
+ number_of_solutions=1, chunksize=500):
+ """Breaks a Polybius substitution cipher using a dictionary and
+ frequency analysis
+
+ >>> polybius_break_mp(polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde'), \
+ 'abcde', 'abcde', \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ (('elephant', <KeywordWrapAlphabet.from_a: 1>, 'abcde', 'abcde', False), \
+ -54.53880...)
+ >>> polybius_break_mp(polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', column_first=True), \
+ 'abcde', 'abcde', \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ (('elephant', <KeywordWrapAlphabet.from_a: 1>, 'abcde', 'abcde', True), \
+ -54.53880...)
+ >>> polybius_break_mp(polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', column_first=False), \
+ 'abcde', 'abcde', \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ (('elephant', <KeywordWrapAlphabet.from_a: 1>, 'abcde', 'abcde', False), \
+ -54.53880...)
+ >>> polybius_break_mp(polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'pqrst', column_first=True), \
+ 'abcde', 'pqrst', \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
+ (('elephant', <KeywordWrapAlphabet.from_a: 1>, 'abcde', 'pqrst', True), \
+ -54.53880...)
+ """
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, word, wrap,
+ column_labels, row_labels, column_first,
+ letters_to_merge,
+ fitness)
+ for word in wordlist
+ for wrap in KeywordWrapAlphabet
+ for column_first in [False, True]]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (limitation of Pool.starmap)
+ breaks = pool.starmap(polybius_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 polybius_break_worker(message, keyword, wrap_alphabet,
+ column_order, row_order, column_first,
+ letters_to_merge,
+ fitness):
+ plaintext = polybius_decipher(message, keyword,
+ column_order, row_order,
+ column_first=column_first,
+ letters_to_merge=letters_to_merge,
+ wrap_alphabet=wrap_alphabet)
+ if plaintext:
+ fit = fitness(plaintext)
+ else:
+ fit = float('-inf')
+ logger.debug('Polybius break attempt using key {0} (wrap={1}, merging {2}), '
+ 'columns as {3}, rows as {4} (column_first={5}) '
+ 'gives fit of {6} and decrypt starting: '
+ '{7}'.format(keyword, wrap_alphabet, letters_to_merge,
+ column_order, row_order, column_first,
+ fit, sanitise(plaintext)[:50]))
+ return (keyword, wrap_alphabet, column_order, row_order, column_first), fit
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
--- /dev/null
+import math
+from enum import Enum
+from itertools import starmap, zip_longest
+from support.utilities import *
+from support.language_models import *
+
+
+from logger import logger
+
+def railfence_encipher(message, height, fillvalue=''):
+ """Railfence cipher.
+ Works by splitting the text into sections, then reading across them to
+ generate the rows in the cipher. The rows are then combined to form the
+ ciphertext.
+
+ Example: the plaintext "hellotherefriends", with a height of four, written
+ out in the railfence as
+ h h i
+ etere*
+ lorfns
+ l e d
+ (with the * showing the one character to finish the last section).
+ Each 'section' is two columns, but unfolded. In the example, the first
+ section is 'hellot'.
+
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 2, fillvalue='!')
+ 'hlohraateerishsslnpeefetotsigaleccpeselteevsmhatetiiaogicotxfretnrifneihr!'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 3, fillvalue='!')
+ 'horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihr!!lhateihsnefttiaece!'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 5, fillvalue='!')
+ 'hresleogcseeemhetaocofrnrner!!lhateihsnefttiaece!!ltvsatiigitxetifih!!oarspeslp!'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 10, fillvalue='!')
+ 'hepisehagitnr!!lernesge!!lmtocerh!!otiletap!!tseaorii!!hassfolc!!evtitffe!!rahsetec!!eixn!'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 3)
+ 'horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihrlhateihsnefttiaece'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 5)
+ 'hresleogcseeemhetaocofrnrnerlhateihsnefttiaeceltvsatiigitxetifihoarspeslp'
+ >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 7)
+ 'haspolsevsetgifrifrlatihnettaeelemtiocxernhorersleesgcptehaiaottneihesfic'
+ """
+ sections = chunks(message, (height - 1) * 2, fillvalue=fillvalue)
+ n_sections = len(sections)
+ # Add the top row
+ rows = [cat([s[0] for s in sections])]
+ # process the middle rows of the grid
+ for r in range(1, height-1):
+ rows += [cat([s[r:r+1] + s[height*2-r-2:height*2-r-1] for s in sections])]
+ # process the bottom row
+ rows += [cat([s[height - 1:height] for s in sections])]
+ # rows += [wcat([s[height - 1] for s in sections])]
+ return cat(rows)
+
+def railfence_decipher(message, height, fillvalue=''):
+ """Railfence decipher.
+ Works by reconstructing the grid used to generate the ciphertext, then
+ unfolding the sections so the text can be concatenated together.
+
+ Example: given the ciphertext 'hhieterelorfnsled' and a height of 4, first
+ work out that the second row has a character missing, find the rows of the
+ grid, then split the section into its two columns.
+
+ 'hhieterelorfnsled' is split into
+ h h i
+ etere
+ lorfns
+ l e d
+ (spaces added for clarity), which is stored in 'rows'. This is then split
+ into 'down_rows' and 'up_rows':
+
+ down_rows:
+ hhi
+ eee
+ lrn
+ led
+
+ up_rows:
+ tr
+ ofs
+
+ These are then zipped together (after the up_rows are reversed) to recover
+ the plaintext.
+
+ Most of the procedure is about finding the correct lengths for each row then
+ splitting the ciphertext into those rows.
+
+ >>> railfence_decipher('hlohraateerishsslnpeefetotsigaleccpeselteevsmhatetiiaogicotxfretnrifneihr!', 2).strip('!')
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihr!!lhateihsnefttiaece!', 3).strip('!')
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('hresleogcseeemhetaocofrnrner!!lhateihsnefttiaece!!ltvsatiigitxetifih!!oarspeslp!', 5).strip('!')
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('hepisehagitnr!!lernesge!!lmtocerh!!otiletap!!tseaorii!!hassfolc!!evtitffe!!rahsetec!!eixn!', 10).strip('!')
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihrlhateihsnefttiaece', 3)
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('hresleogcseeemhetaocofrnrnerlhateihsnefttiaeceltvsatiigitxetifihoarspeslp', 5)
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ >>> railfence_decipher('haspolsevsetgifrifrlatihnettaeelemtiocxernhorersleesgcptehaiaottneihesfic', 7)
+ 'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
+ """
+ # find the number and size of the sections, including how many characters
+ # are missing for a full grid
+ n_sections = math.ceil(len(message) / ((height - 1) * 2))
+ padding_to_add = n_sections * (height - 1) * 2 - len(message)
+ # row_lengths are for the both up rows and down rows
+ row_lengths = [n_sections] * (height - 1) * 2
+ for i in range((height - 1) * 2 - 1, (height - 1) * 2 - (padding_to_add + 1), -1):
+ row_lengths[i] -= 1
+ # folded_rows are the combined row lengths in the middle of the railfence
+ folded_row_lengths = [row_lengths[0]]
+ for i in range(1, height-1):
+ folded_row_lengths += [row_lengths[i] + row_lengths[-i]]
+ folded_row_lengths += [row_lengths[height - 1]]
+ # find the rows that form the railfence grid
+ rows = []
+ row_start = 0
+ for i in folded_row_lengths:
+ rows += [message[row_start:row_start + i]]
+ row_start += i
+ # split the rows into the 'down_rows' (those that form the first column of
+ # a section) and the 'up_rows' (those that ofrm the second column of a
+ # section).
+ down_rows = [rows[0]]
+ up_rows = []
+ for i in range(1, height-1):
+ down_rows += [cat([c for n, c in enumerate(rows[i]) if n % 2 == 0])]
+ up_rows += [cat([c for n, c in enumerate(rows[i]) if n % 2 == 1])]
+ down_rows += [rows[-1]]
+ up_rows.reverse()
+ return cat(c for r in zip_longest(*(down_rows + up_rows), fillvalue='') for c in r)
+
+
+def railfence_break(message, max_key_length=20,
+ fitness=Pletters, chunksize=500):
+ """Breaks a railfence cipher using a matrix of given rank and letter frequencies
+
+
+ """
+
+ sanitised_message = sanitise(message)
+ results = starmap(worker, [(sanitised_message, i, fitness)
+ for i in range(2, max_key_length+1)])
+ return max(results, key=lambda k: k[1])
+
+
+def railfence_break(message, max_key_length=20,
+ fitness=Pbigrams, chunksize=500):
+ """Breaks a railfence cipher using a range of lengths and
+ n-gram frequency analysis
+
+ >>> railfence_break(railfence_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."), \
+ 7)) # doctest: +ELLIPSIS
+ (7, -709.46467226...)
+ >>> railfence_break(railfence_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."), \
+ 7), \
+ fitness=Ptrigrams) # doctest: +ELLIPSIS
+ (7, -997.0129085...)
+ """
+ def worker(message, height, fitness):
+ plaintext = railfence_decipher(message, height)
+ fit = fitness(plaintext)
+ return height, fit
+
+ sanitised_message = sanitise(message)
+ results = starmap(worker, [(sanitised_message, i, fitness)
+ for i in range(2, max_key_length+1)])
+ return max(results, key=lambda k: k[1])
--- /dev/null
+from enum import Enum
+from itertools import starmap, cycle
+import multiprocessing
+from cipher.caesar import *
+from support.utilities import *
+from support.language_models import *
+
+from logger import logger
+
+def vigenere_encipher(message, keyword):
+ """Vigenere encipher
+
+ >>> vigenere_encipher('hello', 'abc')
+ 'hfnlp'
+ """
+ shifts = [pos(l) for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([caesar_encipher_letter(l, k) for l, k in pairs])
+
+def vigenere_decipher(message, keyword):
+ """Vigenere decipher
+
+ >>> vigenere_decipher('hfnlp', 'abc')
+ 'hello'
+ """
+ shifts = [pos(l) for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([caesar_decipher_letter(l, k) for l, k in pairs])
+
+
+def beaufort_encipher(message, keyword):
+ """Beaufort encipher
+
+ >>> beaufort_encipher('inhisjournaldatedtheidesofoctober', 'arcanaimperii')
+ 'sevsvrusyrrxfayyxuteemazudmpjmmwr'
+ """
+ shifts = [pos(l) for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([unpos(k - pos(l)) for l, k in pairs])
+
+beaufort_decipher = beaufort_encipher
+
+beaufort_variant_encipher=vigenere_decipher
+beaufort_variant_decipher=vigenere_encipher
+
+
+def index_of_coincidence_scan(text, max_key_length=20):
+ """Finds the index of coincidence of the text, using different chunk sizes."""
+ stext = sanitise(text)
+ iocs = {}
+ for i in range(1, max_key_length + 1):
+ splits = every_nth(stext, i)
+ mean_ioc = sum(index_of_coincidence(s) for s in splits) / i
+ iocs[i] = mean_ioc
+ return iocs
+
+def vigenere_keyword_break_mp(message, wordlist=keywords, fitness=Pletters,
+ chunksize=500):
+ """Breaks a vigenere cipher using a dictionary and frequency analysis.
+
+ >>> vigenere_keyword_break_mp(vigenere_encipher(sanitise('this is a test ' \
+ 'message for the vigenere decipherment'), 'cat'), \
+ wordlist=['cat', 'elephant', 'kangaroo']) # doctest: +ELLIPSIS
+ ('cat', -52.9472712...)
+ """
+ with multiprocessing.Pool() as pool:
+ helper_args = [(message, word, fitness)
+ for word in wordlist]
+ # Gotcha: the helper function here needs to be defined at the top level
+ # (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)
+ fit = fitness(plaintext)
+ logger.debug('Vigenere keyword break attempt using key {0} gives fit of '
+ '{1} and decrypt starting: {2}'.format(keyword,
+ fit, sanitise(plaintext)[:50]))
+ return keyword, fit
+
+
+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 " \
+ "run. She is ready and so am I. I stole Daniel's pocketbook this " \
+ "afternoon when he left his jacket hanging on the easel in the " \
+ "attic. I jump every time I hear a footstep on the stairs, " \
+ "certain that the theft has been discovered and that I will " \
+ "be caught. The SS officer visits less often now that he is " \
+ "sure"), 'florence')) # doctest: +ELLIPSIS
+ ('florence', -307.5473096...)
+ """
+ def worker(message, key_length, fitness):
+ splits = every_nth(sanitised_message, key_length)
+ key = cat([unpos(caesar_break(s)[0]) for s in splits])
+ plaintext = vigenere_decipher(message, key)
+ fit = fitness(plaintext)
+ 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_sub_break(message, fitness=Pletters):
+ """Breaks one chunk of a Beaufort cipher with frequency analysis
+
+ >>> beaufort_sub_break('samwpplggnnmmyaazgympjapopnwiywwomwspgpjmefwmawx' \
+ 'jafjhxwwwdigxshnlywiamhyshtasxptwueahhytjwsn') # doctest: +ELLIPSIS
+ (0, -117.4492...)
+ >>> beaufort_sub_break('eyprzjjzznxymrygryjqmqhznjrjjapenejznawngnnezgza' \
+ 'dgndknaogpdjneadadazlhkhxkryevrronrmdjnndjlo') # doctest: +ELLIPSIS
+ (17, -114.9598...)
+ """
+ best_shift = 0
+ best_fit = float('-inf')
+ for key in range(26):
+ plaintext = [unpos(key - pos(l)) for l in message]
+ fit = fitness(plaintext)
+ logger.debug('Beaufort sub break attempt using key {0} gives fit of {1} '
+ 'and decrypt starting: {2}'.format(key, fit,
+ plaintext[:50]))
+ if fit > best_fit:
+ best_fit = fit
+ best_key = key
+ logger.info('Beaufort sub break best fit: key {0} gives fit of {1} and '
+ 'decrypt starting: {2}'.format(best_key, best_fit,
+ cat([unpos(best_key - pos(l)) for l in message[:50]])))
+ return best_key, best_fit
+
+
+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 " \
+ "run. She is ready and so am I. I stole Daniel's pocketbook this " \
+ "afternoon when he left his jacket hanging on the easel in the " \
+ "attic. I jump every time I hear a footstep on the stairs, " \
+ "certain that the theft has been discovered and that I will " \
+ "be caught. The SS officer visits less often now " \
+ "that he is sure"), 'florence')) # doctest: +ELLIPSIS
+ ('florence', -307.5473096791...)
+ """
+ def worker(message, key_length, fitness):
+ splits = every_nth(message, key_length)
+ key = cat([unpos(beaufort_sub_break(s)[0]) for s in splits])
+ plaintext = beaufort_decipher(message, key)
+ fit = fitness(plaintext)
+ 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_variant_frequency_break(message, max_key_length=20, fitness=Pletters):
+ """Breaks a Beaufort cipher with frequency analysis
+
+ >>> beaufort_variant_frequency_break(beaufort_variant_encipher(sanitise("It is time to " \
+ "run. She is ready and so am I. I stole Daniel's pocketbook this " \
+ "afternoon when he left his jacket hanging on the easel in the " \
+ "attic. I jump every time I hear a footstep on the stairs, " \
+ "certain that the theft has been discovered and that I will " \
+ "be caught. The SS officer visits less often now " \
+ "that he is sure"), 'florence')) # doctest: +ELLIPSIS
+ ('florence', -307.5473096791...)
+ """
+ def worker(message, key_length, fitness):
+ splits = every_nth(sanitised_message, key_length)
+ key = cat([unpos(-caesar_break(s)[0]) for s in splits])
+ plaintext = beaufort_variant_decipher(message, key)
+ fit = fitness(plaintext)
+ 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])
+
+if __name__ == "__main__":
+ import doctest
\ No newline at end of file
projects / szyfrow.git / commitdiff