Psu Encrypt

Graduate Student Version (80bit key)

• Graham Seamans
• [email protected]

To Run

• Place the key into ./key.txt. Hex but with no leading '0x'.
• Place the plaintext into ./plaintext.txt or the ciphertext into ./ciphertext.txt
• Run: python src/main.py e or python src/main.py d where e is encrypt and d is decrypt. If you don't provide an arumgent you will be prompted.
• Find the plaintext or cypher text in the appropriate file.

Notes

• This runs with ASCII encode and decode so things will get weird with UTF-8 files, although the majority of the text will be just fine.

Included Files

• ./plaintext.txt - Put the plain text here to encrypt or find it here after decryption.
• ./ciphertext.txt - Put the cipher text here to decrypt or find it here after encryption.
• ./key.txt - The key goes here. No '0x' before the key. 80bit key only.
• ./src/main.py - Takes user input about whether to encrypt and decrypt and interfaces with cipher.py
• ./src/cipher.py - Largely runs the show. Reads and writes to files and calls the festel.py with blocks to encrypt or decrypt.
• ./src/festel.py - The festel cipher. Gets keys from key.py. Has the f and g functions.
• ./src/key.py - Generates the keys. Makes a list of lists of all subkeys in encrytion order.
• ./src/ftable.py - The ftable and lookup function.
• ./src/utility.py - Functions to translate between and combine ascii, hex, binary, binary strings, and such.