from numpy import matrix
from numpy import linalg
from language_models import *
+import pprint
## Utility functions
cat = ''.join
wcat = ' '.join
+lcat = '\n'.join
def pos(letter):
if letter in string.ascii_lowercase:
>>> vigenere_encipher('hello', 'abc')
'hfnlp'
"""
- shifts = [ord(l) - ord('a') for l in sanitise(keyword)]
+ 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])
>>> vigenere_decipher('hfnlp', 'abc')
'hello'
"""
- shifts = [ord(l) - ord('a') for l in sanitise(keyword)]
+ 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])
-beaufort_encipher=vigenere_decipher
-beaufort_decipher=vigenere_encipher
+
+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 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 transpositions_of(keyword):
padding = fillvalue[0] * (n - len(sanitised_message) % n)
else:
padding = ''
- message = [ord(c) - ord('a') for c in sanitised_message + 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([chr(int(round(l)) % 26 + ord('a'))
+ return cat([unpos(round(l))
for l in sum(enciphered_chunks, [])])
def hill_decipher(matrix, message, fillvalue='a'):
return cat(plaintext_list)
+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)
+
class PocketEnigma(object):
"""A pocket enigma machine
The wheel is internally represented as a 26-element list self.wheel_map,
self.validate_wheel_spec(wheel)
self.make_wheel_map(wheel)
if position in string.ascii_lowercase:
- self.position = ord(position) - ord('a')
+ self.position = pos(position)
else:
self.position = position
self.validate_wheel_spec(wheel_spec)
self.wheel_map = [0] * 26
for p in wheel_spec:
- self.wheel_map[ord(p[0]) - ord('a')] = ord(p[1]) - ord('a')
- self.wheel_map[ord(p[1]) - ord('a')] = ord(p[0]) - ord('a')
+ 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):
''
"""
if letter in string.ascii_lowercase:
- return chr(
- (self.wheel_map[(ord(letter) - ord('a') - self.position) % 26] +
- self.position) % 26 +
- ord('a'))
+ return unpos(
+ (self.wheel_map[(pos(letter) - self.position) % 26] +
+ self.position))
else:
return ''
>>> pe.set_position('z')
25
"""
- self.position = ord(position) - ord('a')
+ self.position = pos(position)
return self.position