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 | */ |
23 | static inline bool ppp_proto_is_valid(u16 proto) |
24 | { |
25 | return !!((proto & 0x0101) == 0x0001); |
26 | } |
27 | |
28 | #endif /* _PPP_DEFS_H_ */ |
29 | |