miniproto.crypto.mtproto.derive_aes_key_iv

miniproto.crypto.mtproto.derive_aes_key_iv

derive_aes_key_iv(auth_key: bytes, msg_key: bytes, *, client_to_server: bool = True) -> tuple[bytes, bytes]

Derive the AES-256 key and 32-byte IGE IV required by MTProto 2.0.

Parameters:

• auth_key (bytes) – Exactly 256 bytes of authorization-key material.
• msg_key (bytes) – Exactly 16 bytes produced for the same traffic direction.
• client_to_server (bool) – Selects the client-to-server offset by default; set false for server-to-client traffic.

Returns:

• tuple[bytes, bytes] – A (key, iv) pair for AES-256-IGE.

Raises:

• ValueError – If the authorization key or message key has an invalid length.

Native and fallback implementations are output-compatible. This only derives material; it never transmits or clears the supplied key bytes.