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ec47cae | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 | #!/usr/bin/env python3
"""
Encrypt a plaintext using the protocol's cipher.
Usage: python encrypt.py <plaintext_hex> [--key-hex KEY] [--iv-hex IV]
Input: plaintext as a hexadecimal string
Output: ciphertext as a hexadecimal string on stdout
This script applies ONLY the cipher layer -- no compression,
base64, or transport encoding.
"""
import sys
def encrypt(plaintext: bytes, key: bytes | None = None, iv: bytes | None = None) -> bytes:
"""Encrypt plaintext bytes and return ciphertext bytes.
Implement the cipher used by this protocol.
Do not apply compression, base64, or transport encoding.
"""
raise NotImplementedError("TODO: implement encryption")
def main():
if len(sys.argv) < 2:
print(f"Usage: {sys.argv[0]} <plaintext_hex> [--key-hex KEY] [--iv-hex IV]",
file=sys.stderr)
sys.exit(1)
plaintext = bytes.fromhex(sys.argv[1])
key_hex = None
iv_hex = None
i = 2
while i < len(sys.argv):
if sys.argv[i] == "--key-hex" and i + 1 < len(sys.argv):
key_hex = sys.argv[i + 1]
i += 2
elif sys.argv[i] == "--iv-hex" and i + 1 < len(sys.argv):
iv_hex = sys.argv[i + 1]
i += 2
else:
i += 1
key = bytes.fromhex(key_hex) if key_hex else None
iv = bytes.fromhex(iv_hex) if iv_hex else None
ciphertext = encrypt(plaintext, key, iv)
print(ciphertext.hex())
if __name__ == "__main__":
main()
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