68 lines
1.7 KiB
Python
68 lines
1.7 KiB
Python
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#!/usr/bin/env python3
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import os
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from Pailier import *
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from Crypto.Util.number import *
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with open("/flag.txt", "rb") as f:
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flag_bytes = f.read()
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key = os.urandom(66)
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key_int = bytes_to_long(key)
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cipher = pailier()
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while True:
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print("1. encrypt")
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print("2. bingo")
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print("3. decrypt")
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print("4. key?")
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try:
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inp = int(input("> "))
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except (ValueError, EOFError):
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print("Invalid input")
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continue
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if inp == 1:
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print("pt (hex)")
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try:
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inp = input("> ")
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ct = cipher.encrypt(int(inp, 16))
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print('ct : ', '{0:x}'.format(ct))
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except (ValueError, EOFError):
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print("Invalid hex input")
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elif inp == 2:
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print("key (hex)")
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try:
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user_hex = input("> ").strip()
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user_key = bytes.fromhex(user_hex)
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if len(user_key) == 66 and user_key == key:
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try:
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print(flag_bytes.decode())
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except Exception:
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print(flag_bytes.hex())
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else:
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print("nope")
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except (ValueError, EOFError):
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print("nope")
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elif inp == 3:
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print("ct (hex)")
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try:
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inp = input("> ")
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pt = cipher.decrypt(int(inp, 16))
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print('pt : ', '{0:x}'.format(pt))
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except (ValueError, EOFError):
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print("Invalid hex input")
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elif inp == 4:
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try:
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ct = cipher.encrypt(key_int)
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print('ct : ', '{0:x}'.format(ct))
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except Exception:
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print("Encryption error")
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else:
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exit()
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