miniproto.crypto.native.mtproto_decode_message

miniproto.crypto.native.mtproto_decode_message

mtproto_decode_message(auth_key: bytes, packet: BytesLike, *, client_to_server: bool = False) -> tuple[bytes, int, int, int, int, bytes, bytes]

Decrypt, authenticate, and parse an MTProto encrypted message.

Parameters:

• auth_key (bytes) – Exactly 256 bytes of authorization-key material.
• packet (BytesLike) – Packet containing the 8-byte auth-key ID, 16-byte message key, and block-aligned ciphertext.
• client_to_server (bool) – Defaults to false for inbound server-to-client packets.

Returns:

• tuple[bytes, int, int, int, int, bytes, bytes] – (auth_key_id, server_salt, session_id, msg_id, seq_no, body, padding).

Raises:

• ValueError – If the packet is malformed, keys mismatch, lengths are invalid, or padding violates MTProto 2.0 constraints.

This checks the packet’s auth-key identifier and message key, but transport ordering, replay handling, and message semantics remain the caller’s job.