1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * ppp_defs.h - PPP definitions.
4 *
5 * Copyright 1994-2000 Paul Mackerras.
6 */
7#ifndef _PPP_DEFS_H_
8#define _PPP_DEFS_H_
9
10#include <linux/crc-ccitt.h>
11#include <uapi/linux/ppp_defs.h>
12
13#define PPP_FCS(fcs, c) crc_ccitt_byte(fcs, c)
14
15/**
16 * ppp_proto_is_valid - checks if PPP protocol is valid
17 * @proto: PPP protocol
18 *
19 * Assumes proto is not compressed.
20 * Protocol is valid if the value is odd and the least significant bit of the
21 * most significant octet is 0 (see RFC 1661, section 2).
22 */
23static inline bool ppp_proto_is_valid(u16 proto)
24{
25 return !!((proto & 0x0101) == 0x0001);
26}
27
28#endif /* _PPP_DEFS_H_ */
29