45 lines
1.0 KiB
Python
45 lines
1.0 KiB
Python
from Crypto.Cipher import AES
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from Crypto.Util.Padding import pad, unpad
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from Crypto.Random import get_random_bytes
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from random import randint
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from secret import flag
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assert (len(flag) == len("CRYPTO25{}") + 36)
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key = get_random_bytes(24)
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padding1_len = randint(1, 6)
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padding1 = get_random_bytes(padding1_len)
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padding2 = get_random_bytes(10 - padding1_len)
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flag = flag.encode()
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def encrypt() -> bytes:
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data = bytes.fromhex(input("> ").strip())
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payload = padding1 + data + padding2 + flag
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cipher = AES.new(key=key, mode=AES.MODE_ECB)
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print(cipher.encrypt(pad(payload, AES.block_size)).hex())
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def main():
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menu = \
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"What do you want to do?\n" + \
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"quit - quit the program\n" + \
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"enc - encrypt something\n" + \
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"help - show this menu again\n" + \
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"> "
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while True:
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cmd = input(menu).strip()
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if cmd == "quit":
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break
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elif cmd == "help":
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continue
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elif cmd == "enc":
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encrypt()
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if __name__ == '__main__':
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main()
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