Source code for CrackingCodes.Ch12.transpositionHacker

"""Transposition Cipher Hacker

Implements a function that can hack a transposition cipher encrypted message.

Note:
    * https://www.nostarch.com/crackingcodes/ (BSD Licensed)
"""

from pythontutorials.books.CrackingCodes.Ch11.detectEnglish import isEnglish
from pythontutorials.books.CrackingCodes.Ch08.transpositionDecrypt import decryptMessage


[docs]def main(): from pyperclip import copy # You might want to copy & paste this text from the source code at # https://www.nostarch.com/crackingcodes/: myMessage = """AaKoosoeDe5 b5sn ma reno ora'lhlrrceey e enlh na indeit n uhoretrm au ieu v er Ne2 gmanw,forwnlbsya apor tE.no euarisfatt e mealefedhsppmgAnlnoe(c -or)alat r lw o eb nglom,Ain one dtes ilhetcdba. t tg eturmudg,tfl1e1 v nitiaicynhrCsaemie-sp ncgHt nie cetrgmnoa yc r,ieaa toesa- e a0m82e1w shcnth ekh gaecnpeutaaieetgn iodhso d ro hAe snrsfcegrt NCsLc b17m8aEheideikfr aBercaeu thllnrshicwsg etriebruaisss d iorr.""" hackedMessage = hackTransposition(myMessage) if hackedMessage is None: print('Failed to hack encryption.') else: print('Copying hacked message to clipboard:') print(hackedMessage) copy(hackedMessage)
[docs]def hackTransposition(message: str): """Hacks transposition cipher encrypted messages Brute-forces a given encrypted message by looping through all the keys, checking if the result is English, and prompting the user for confirmation of decryption. Args: message: String with message to brute-force. Returns: Prints out possible results and prompts user for confirmation. If confirmed, prints out and returns full decrypted message, otherwise returns None. """ print('Hacking...') # Python programs can be stopped at any time by pressing # Ctrl-C (on Windows) or Ctrl-D (on macOS and Linux): print('(Press Ctl-C (on Windows) or Ctrl-D (on macOS and Linux) to quit at any time.)') # Brute-force by looping through every possible key: for key in range(1, len(message)): print('Trying key #%s...' % (key)) decryptedText = decryptMessage(key, message) if isEnglish(decryptedText): # Ask user if this is the correct decryption: print() print('Possible encryption hack:') print('Key %s: %s' % (key, decryptedText[:100])) print() print('Enter D if done, anything else to continue hacking:') response = input('> ') if response.strip().upper().startswith('D'): return decryptedText return None
if __name__ == '__main__': main()