17 lines
494 B
Python
Executable File
17 lines
494 B
Python
Executable File
#!/usr/bin/env nix-shell
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#!nix-shell -i python3 -p python3
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def decrypt(ciphertext: str, key: int):
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for letter in ciphertext:
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shifted = chr(((ord(letter) - ord('a') + key + 26) % 26) + ord('a'))
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print(shifted, end='')
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print()
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if __name__ == "__main__":
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with open('ciphertext') as file:
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enc = file.read().strip()[len('picoCTF{'):-len('}')]
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# Note: seems to be the last one, "crossing the rubicon"
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for shift in range(26):
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decrypt(enc, shift)
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