1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	from tahoe:	in_cksum.c	1.2	86/01/05
32 *	from:		@(#)in_cksum.c	1.3 (Berkeley) 1/19/91
33 *	from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
34 *	from: src/sys/alpha/include/in_cksum.h,v 1.7 2005/03/02 21:33:20 joerg
35 * $FreeBSD$
36 */
37
38#ifndef _MACHINE_IN_CKSUM_H_
39#define	_MACHINE_IN_CKSUM_H_	1
40
41#include <sys/cdefs.h>
42
43#define	in_cksum(m, len)	in_cksum_skip(m, len, 0)
44
45#if defined(IPVERSION) && (IPVERSION == 4)
46/*
47 * It it useful to have an Internet checksum routine which is inlineable
48 * and optimized specifically for the task of computing IP header checksums
49 * in the normal case (where there are no options and the header length is
50 * therefore always exactly five 32-bit words.
51 */
52#ifdef __CC_SUPPORTS___INLINE
53
54static __inline void
55in_cksum_update(struct ip *ip)
56{
57	int __tmpsum;
58	__tmpsum = (int)ntohs(ip->ip_sum) + 256;
59	ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16));
60}
61
62#else
63
64#define	in_cksum_update(ip)						\
65	do {								\
66		int __tmpsum;						\
67		__tmpsum = (int)ntohs(ip->ip_sum) + 256;		\
68		ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16));	\
69	} while(0)
70
71#endif
72#endif
73
74#ifdef _KERNEL
75#if defined(IPVERSION) && (IPVERSION == 4)
76u_int in_cksum_hdr(const struct ip *ip);
77#endif
78u_short in_addword(u_short sum, u_short b);
79u_short in_pseudo(u_int sum, u_int b, u_int c);
80u_short in_cksum_skip(struct mbuf *m, int len, int skip);
81#endif
82
83#endif /* _MACHINE_IN_CKSUM_H_ */
84