MyCaesarCipher 0.2.0

Simple cryptographic substitution-based cipher for encoding plaintext.

MyCaesarCipher

Simple cryptographic substitution-based cipher for encoding plaintext.

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About

• The Caesar Cipher is one of the most simple and well known encryption techniques.

  • Each letter in the plaintext entry is replaced by a letter some fixed number of positions down the alphabet.

• This project was created as an exercise while I was taking the "Cracking Codes with Python" course - which I highly recommend for both beginners and experienced python programmers interested in cryptography!

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Installation

Using pip (Recommended)

Easiest method. Highly recommended over manual installation.

• Run the following to install MyCaesarCipher using pip:

pip install MyCaesarCipher

• You should now be able to import/run MyCaesarCipher within your python environment by entering the following:

>>> from MyCaesarCipher import CaesarCipher
...

• Done!

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Manual Installation

Not recommended.

1. Before use, navigate to intended installation location, and create a new directory.

2. Either clone repository with the git client of your preference, or download and extract the source code zip archive from the "releases" page, to the newly created directory.

3. Install all dependencies for this package within said directory using:

   pip install -r requirements.txt
   

   • (Optional) move installation directory to "~Python/Libs/site_packages/" to be able to import this package to a Python program like any other importable package.

• Done!

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Usage

• Within a Python environment or .py project, simply import the MyCaesarCipher module to start encryption/decryption of ciphers.

Message Encryption

• For encrypting text, use the CaesarCipher.encrypt class method:

>>> from MyCaesarCipher import CaesarCipher

>>> cipher = CaesarCipher() # Create new class instance.
>>> msg = 'Test Cipher'
>>> encoder.encrypt(text=msg, key=200, print_to_console=True)

> Original Msg : Test Cipher
> Shift-Key : 200
> Encrypted Result: Lwkl Uahzwj

• Therefore the final encrypted result of "Test Cipher" using a shift-key of 200 is:

  • "LwklfUahzwj".

• Note that the key: int parameter is optional, and if not provided, a random key between 1 and 25 will be generated:

>>> cipher.encrypt('Test Cipher', print_to_console=True)

> Original Msg : Test Cipher
> Shift-key : 19
> Encrypted Result: Mxlm Vbiaxk

>>> cipher.encrypt('Test Cipher', print_to_console=True)

> Original Msg : Test Cipher
> Shift-key : 24
> Encrypted Result: Rcqr Agnfcp

>>> cipher.encrypt('Test Cipher', print_to_console=True)

> Original Msg : Test Cipher
> Shift-key : 4
> Encrypted Result: Xiwx Gmtliv

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Message Decryption

• For decrypting text, use the CaesarCipher.decrypt class method:

>>> from MyCaesarCipher import CaesarCipher

>>> cipher = CaesarCipher() # Create new class instance.
>>> code = 'Ozno Xdkczm'
>>> cipher.decrypt(text=code, print_to_console=True)

> Decrypted Shift-Key 0 : Ozno Xdkczm

> Decrypted Shift-Key 1 : Nymn Wcjbyl

> Decrypted Shift-Key 2 : Mxlm Vbiaxk

> Decrypted Shift-Key 3 : Lwkl Uahzwj

> Decrypted Shift-Key 4 : Kvjk Tzgyvi

> Decrypted Shift-Key 5 : Juij Syfxuh

> Decrypted Shift-Key 6 : Ithi Rxewtg

> Decrypted Shift-Key 7 : Hsgh Qwdvsf

> Decrypted Shift-Key 8 : Grfg Pvcure

> Decrypted Shift-Key 9 : Fqef Oubtqd

> Decrypted Shift-Key 10 : Epde Ntaspc

> Decrypted Shift-Key 11 : Docd Mszrob

> Decrypted Shift-Key 12 : Cnbc Lryqna

> Decrypted Shift-Key 13 : Bmab Kqxpmz

> Decrypted Shift-Key 14 : Alza Jpwoly

> Decrypted Shift-Key 15 : Zkyz Iovnkx

> Decrypted Shift-Key 16 : Yjxy Hnumjw

> Decrypted Shift-Key 17 : Xiwx Gmtliv

> Decrypted Shift-Key 18 : Whvw Flskhu

> Decrypted Shift-Key 19 : Vguv Ekrjgt

> Decrypted Shift-Key 20 : Uftu Djqifs

> Decrypted Shift-Key 21 : Test Cipher # <-- Correct Result

> Decrypted Shift-Key 22 : Sdrs Bhogdq

> Decrypted Shift-Key 23 : Rcqr Agnfcp

> Decrypted Shift-Key 24 : Qbpq Zfmebo

> Decrypted Shift-Key 25 : Paop Yeldan

• The CaesarCipher.decrypt method will return all possible shifted-key variations of the given encrypted message.

• Generally, the most legible key output will be the correct decrypted message, assuming the encrypted message was legible to begin with.

• Regardless, the correct output MUST be one of the output values due to the limitations of the algorithm being tied to the length of the alphabet [26] and amount of possible numbers [0-9].

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Contact

• If you have any questions, comments, or concerns that cannot be alleviated through the project's GitHub repository, please feel free to contact me through my email address:

  • [e-mail]