fad38387af
I think this is a form of symmetric encryption where the passphrase (e.g. "ICE") is repeated (e.g. "ICEICEICEICEI...") until it matches the length of the cleartext string; after that, the two byte-strings are XOR'd against one another and then encoded as hexadecimal creating the ciphertext. Change-Id: Ib148f06d6c42a41377d1df1f0738d77da935a9f6 Reviewed-on: https://cl.tvl.fyi/c/depot/+/4789 Tested-by: BuildkiteCI Reviewed-by: wpcarro <wpcarro@gmail.com> Autosubmit: wpcarro <wpcarro@gmail.com>
16 lines
611 B
Python
16 lines
611 B
Python
def encrypt_repeating_key(x, key):
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result = b""
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for i in range(len(x)):
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b = ord(x[i]) ^ ord(key[i % len(key)])
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result += b.to_bytes(1, 'big')
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return result.hex()
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cleartext = "Burning 'em, if you ain't quick and nimble\nI go crazy when I hear a cymbal"
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expected = "0b3637272a2b2e63622c2e69692a23693a2a3c6324202d623d63343c2a26226324272765272a282b2f20430a652e2c652a3124333a653e2b2027630c692b20283165286326302e27282f"
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run_tests = False
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if run_tests:
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ciphertext = encrypt_repeating_key(cleartext, "ICE")
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print(ciphertext)
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assert ciphertext == expected
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print("Success!")
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