generated from mwc/lab_encryption
4fc2cfe227
1. Writing my own code definitely helped me understand the problem better. It was kind of lucky that the most common character in each of the secret texts was in fact " ". It made me understand the work that the cipher is doing better. 2. I watched like 3 different youtube videos about the Kasiski examination process after reading the wiki page. I quickly used "the" to get a difference to the next "the" that mapped the same as 42, so I knew the keyword had to be a multiple of 2,3, or 7. I tried the process with 3 and got nowhere, so I tried it with 6 on a whim. I got the first two letters of the code to be PY, then I couldn't figure out the third so I skipped it, and got the 4th letter to be H, so I made the guess that the keyword was PYTHON and I was right!
49 lines
1.2 KiB
Python
49 lines
1.2 KiB
Python
from easybits import Bits
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from collections import Counter
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from ciphers.caesar import CaesarCipher
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def crack_caesar(ciphertext):
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fulltext = ''
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with open(ciphertext,"r") as text:
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for line in text:
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cleanline = line.strip()
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for char in cleanline:
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fulltext += char
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counter = Counter(fulltext)
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countdict = dict(counter)
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print(countdict)
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maximum = max(countdict.values())
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target = ''
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for char in countdict:
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if countdict[char] == maximum:
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target = char
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diff = Bits(target,8).int - Bits(" ",8).int
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cipher = CaesarCipher(diff)
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decryptedtext = cipher.decrypt(fulltext) #I included this part to double check that the function works
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return diff, decryptedtext
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def polyalpha_helper(text): #used to help crack the code!
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groups = [[],[],[],[],[],[]]
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for i in range(len(text)):
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for n in range(6):
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if i%6 == n:
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groups[n].append(text[i])
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groupmax = []
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for alist in groups:
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counter = dict(Counter(alist))
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sorter = sorted(counter.items(), key=lambda item: item[1], reverse = True)
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max = sorter[0]
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groupmax.append(max)
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print(groupmax)
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