Welcome to crypyto’s documentation!

crypyto is a Python package that provides a set of cryptographic tools with simple use to your applications.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Dependencies

• Python >= 3.5
• Python packages (no need to worry if you use pip to install crypyto):
  • unidecode to normalize strings
  • Pillow to handle images

Installing

The easiest way to install crypyto is by using pip:

pip install crypyto

You can also clone this repository using git

git clone https://github.com/yanorestes/crypyto.git

Ciphers

This module provides simple usage of functions related to a list of ciphers

Ciphers crypyto supports:

• Polybius Square
• Atbash
• Caesar Cipher
• ROT13
• Affine Cipher
• Rail Fence Cipher

Polybius Square

class crypyto.ciphers.PolybiusSquare(width, height, abc='ABCDEFGHIJKLMNOPQRSTUVWXYZ', ij=True)

PolybiusSquare represents a Polybius Square cipher manipulator

Parameters:

• width (int) – The square’s width. Must be at least 1. Width times height must be greater than the alphabet length
• height (int) – The square’s height. Must be at least 1. Height times width must be greater than the alphabet length
• abc (str) – The alphabet used in the square. Defaults to string.ascii_uppercase
• ij (bool) – Whether ‘i’ and ‘j’ are treated as the same letter. Defaults to True

Raises:

• ValueError – When width is smaller than 1
• ValueError – When width * height is smaller than len(abc)

decrypt(cipher)

Returns decrypted cipher (str)

Parameters:cipher (str) – The cipher to be decrypted. May or may not contain the square size at the beggining (e.g. ‘5x5#’) Raises:ValueError – When cipher doesn’t match the Polybius Square pattern

Examples

>>> from crypyto.ciphers import PolybiusSquare
>>> ps = PolybiusSquare(5, 5)
>>> ps.decrypt('5x5#5-1;3-3;3-1;2-4;4-5;5-3;4-4;5-1;4-1;2-3;5-1;3-4;3-4;1-1;2-2;5-1')
'ENCRYPTEDMESSAGE'

encrypt(text)

Returns encrypted text (str)

Parameters:text (str) – The text to be encrypted

Examples

>>> from crypyto.ciphers import PolybiusSquare
>>> ps = PolybiusSquare(5, 5)
>>> ps.encrypt('EncryptedMessage')
'5x5#5-1;3-3;3-1;2-4;4-5;5-3;4-4;5-1;4-1;2-3;5-1;3-4;3-4;1-1;2-2;5-1'

Atbash

class crypyto.ciphers.Atbash(abc='ABCDEFGHIJKLMNOPQRSTUVWXYZ')

Atbash represents an Atbash cipher manipulator

Parameters:abc (str) – The alphabet used in the cipher. Defaults to string.ascii_uppercase

decrypt(cipher, decode_unicode=True)

Returns decrypted text (str)

Parameters:

• cipher (str) – The cipher to be decrypted
• decode_unicode (bool) – Whether the cipher should have unicode characters converted to ascii before decrypting. Defautls to True

Examples

>>> from crypyto.ciphers import Atbash
>>> atbash = Atbash()
>>> atbash.decrypt('SVOOL, DLIOW!')
'HELLO, WORLD!'

encrypt(text, decode_unicode=True)

Returns encrypted text (str)

Parameters:

• text (str) – The text to be encrypted
• decode_unicode (bool) – Whether the text should have unicode characters converted to ascii before encrypting. Defautls to True

Examples

>>> from crypyto.ciphers import Atbash
>>> atbash = Atbash()
>>> atbash.encrypt('Hello, world!')
'SVOOL, DLIOW!'

Caesar Cipher

class crypyto.ciphers.Caesar(abc='ABCDEFGHIJKLMNOPQRSTUVWXYZ', key=1)

Caesar represents a Caesar cipher manipulator

Parameters:

• abc (str) – The alphabet used in the cipher. Defaults to string.ascii_uppercase
• key (int) – The key to initialize the cipher manipulator. Defaults to 1

brute_force(cipher, decode_unicode=True, output_file=None)

Prints (to stdout or specified file) all possible results

Parameters:

• cipher (str) – The cipher to be decrypted
• decode_unicode (bool) – Whether the cipher should have unicode characters converted to ascii before decrypting. Defautls to True
• output_file (str|None) – The filename of the file the results are gonna be printed. Defaults to None, which indicated printing on stdout

Examples

>>> from crypyto.ciphers import Caesar
>>> caesar = Caesar()
>>> caesar.brute_force('MJQQT, BTWQI!')
NKRRU, CUXRJ!
OLSSV, DVYSK!
...
HELLO, WORLD!
IFMMP, XPSME!
...

decrypt(cipher, decode_unicode=True, key=None)

Returns decrypted cipher (str)

Parameters:

• cipher (str) – The cipher to be decrypted
• decode_unicode (bool) – Whether the cipher should have unicode characters converted to ascii before decrypting. Defautls to True
• key (int|None) – The key used to decrypt. Defaults to None, which uses the value from self.key

Examples

>>> from crypyto.ciphers import Caesar
>>> caesar = Caesar(key=5)
>>> caesar.decrypt('MJQQT, BTWQI!')
'HELLO, WORLD!'

encrypt(text, decode_unicode=True, key=None)

Returns encrypted text (str)

Parameters:

• text (str) – The text to be encrypted
• decode_unicode (bool) – Whether the text should have unicode characters converted to ascii before encrypting. Defautls to True
• key (int|None) – The key used to encrypt. Defaults to None, which uses the value from self.key

Examples

>>> from crypyto.ciphers import Caesar
>>> caesar = Caesar(key=5)
>>> caesar.encrypt('Hello, world!')
'MJQQT, BTWQI!'

ROT13

A Caesar object with default key value of 13

Examples:

>>> from crypyto.ciphers import ROT13
>>> ROT13.encrypt('Hello, world!')
'URYYB, JBEYQ!'
>>> ROT13.encrypt('URYYB, JBEYQ!')
'HELLO, WORLD!'

Affine Cipher

class crypyto.ciphers.Affine(a, b, abc='ABCDEFGHIJKLMNOPQRSTUVWXYZ')

Affine represents an Affine cipher manipulator

Parameters:

• a (int) – Value of a. Must be coprime to len(abc)
• b (int) – Value of b
• abc (str) – The alphabet used in the cipher. Defaults to string.ascii_uppercase

Raises:

ValueError – If a is not coprime to len(abc)

decrypt(cipher)

Returns decrypted cipher (str)

Parameters:cipher (str) – Cipher to be decrypted

Examples

>>> from crypyto.cipher import Affine
>>> af = Affine(a=5, b=8)
>>> af.decrypt('RCLLA, OAPLX!')
'HELLO, WORLD!'

encrypt(text)

Returns encrypted text (str)

Parameters:text (str) – Text to be encrypted

Examples

>>> from crypyto.cipher import Affine
>>> af = Affine(a=5, b=8)
>>> af.encrypt('Hello, world!')
'RCLLA, OAPLX!'

Rail Fence Cipher

class crypyto.ciphers.RailFence(n_rails, only_alnum=False, direction='D')

RailFence represents a Rail Fence cipher manipulator

Parameters:

• n_rails (int) – Number of rails
• only_alnum (bool) – Whether the manipulator will only encrypt alphanumerical characters. Defaults to False
• direction (str) – Default direction to start zigzagging. Must be 'D' (Downwards) or 'U' (Upwards). Defaults to 'D'

Raises:

ValueError – When direction doesn’t start with 'U' or 'D'

brute_force(cipher, output_file=None)

Prints (to stdout or specified file) all possible decrypted results

Parameters:

• cipher (str) – The cipher to be decrypted
• output_file (str|None) – The filename of the file the results are gonna be printed. Defaults to None, which indicated printing on stdout

Examples

>>> from crypyto.ciphers import RailFence
>>> rf = RailFence(n_rails=1, only_alnum=True)
>>> rf.decrypt('WECRLTEERDSOEEFEAOCAIVDEN')
There are 46 possible results. You can specify an output file in the parameter output_file
Are you sure you want to print them all (Y/N)?
Y
WEEFCERALOTCEAEIRVDDSEONE
WEAREDISCOVEREDFLEEATONCE
...
NEDVIACOAEFEEOSDREETREWCL
NEDVIACOAEFEEOSDREETLREWC

decrypt(cipher)

Returns decrypted cipher

Parameters:cipher (str) – The cipher to be decrypted

Examples

>>> from crypyto.cipher import RailFence
>>> rf = RailFence(n_rails=3, only_alnum=True)
>>> rf.decrypt('WECRLTEERDSOEEFEAOCAIVDEN')
'WEAREDISCOVEREDFLEEATONCE'

encrypt(text)

Returns encrypted text (str)

Parameters:text (str) – The text to be encrypted

Examples

>>> from crypyto.cipher import RailFence
>>> rf = RailFence(n_rails=3, only_alnum=True)
>>> rf.encrypt('WE ARE DISCOVERED. FLEE AT ONCE')
'WECRLTEERDSOEEFEAOCAIVDEN'

Substitution Alphabets

This module provides simple usage of functions related to substitutions alphabets

Alphabets crypyto supports:

• Morse Code
• Image Substitution
• Templar Cipher

Morse Code

class crypyto.substitution_alphabets.Morse(word_splitter='/')

Morse represents a Morse Code manipulator

Parameters:word_splitter (str) – A string which will be used to indicate words separation. Defaults to '/'

decrypt(cipher)

Returns translated cipher into plain text

Parameters:cipher (str) – The morse code to be translated into plain text

Examples

>>> from crypyto.substitution_alphabets import Morse
>>> morse = Morse()
>>> morse.decrypt('.... . .-.. .-.. --- --..-- / .-- --- .-. .-.. -.. -.-.--')
'HELLO, WORLD!'

encrypt(text)

Returns translated text into Morse Code (str)

Parameters:text (str) – The text to be translated into Morse Code

Examples

>>> from crypyto.subsititution_alphabets import Morse
>>> morse = Morse()
>>> morse.encrypt('Hello, world!')
'.... . .-.. .-.. --- --..-- / .-- --- .-. .-.. -.. -.-.--'

Image Substitution

class crypyto.substitution_alphabets.ImageSubstitution(abc, directory, extension)

ImageSubstitution is a base class which is used by all the image-based alphabets

Parameters:

• abc (str) – The plain text alphabet this image-based alphabet have a translation to
• directory (str) – The directory where the image files are located (inside this package -> /static/directory/)
• extension (str) – The file extension the image files use

encrypt(text, filename='output.png', max_in_line=30)

Creates an image file with the translated text

Parameters:

• text (str) – Text to be translated to the specified substitution alphabet
• filename (str) – The filename of the image file with the translated text. Defaults to 'output.png'
• max_in_line (int) – The max number of letters per line. Defaults to 30

Templar Cipher

Templar represents an ImageSubstitution object adjusted to the Templar Cipher

Examples:

>>> from crypyto.substitution_alphabets import Templar
>>> Templar.encrypt('Hello, world!', 'templar_hello.png')
>>> Templar.encrypt('Hello, world!', 'templar_hello_max.png', 5)

templar_hello.png:

Encrypted hello world

templar_hello_max.png:

Encrypted hello world (5 letters per line)