in_cksum.h revision 331722 
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	from tahoe:	in_cksum.c	1.2	86/01/05
30 *	from:		@(#)in_cksum.c	1.3 (Berkeley) 1/19/91
31 *	from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
32 * $FreeBSD: stable/11/sys/powerpc/include/in_cksum.h 331722 2018-03-29 02:50:57Z eadler $
33 */
34
35#ifndef _MACHINE_IN_CKSUM_H_
36#define	_MACHINE_IN_CKSUM_H_	1
37
38#include <sys/cdefs.h>
39
40#define in_cksum(m, len)	in_cksum_skip(m, len, 0)
41
42#if defined(IPVERSION) && (IPVERSION == 4)
43/*
44 * It it useful to have an Internet checksum routine which is inlineable
45 * and optimized specifically for the task of computing IP header checksums
46 * in the normal case (where there are no options and the header length is
47 * therefore always exactly five 32-bit words.
48 */
49#ifdef __CC_SUPPORTS___INLINE
50
51static __inline void
52in_cksum_update(struct ip *ip)
53{
54	int __tmpsum;
55	__tmpsum = (int)ntohs(ip->ip_sum) + 256;
56	ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16));
57}
58
59#else
60
61#define	in_cksum_update(ip) \
62	do { \
63		int __tmpsum; \
64		__tmpsum = (int)ntohs(ip->ip_sum) + 256; \
65		ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); \
66	} while(0)
67
68#endif
69#endif
70
71#ifdef _KERNEL
72#if defined(IPVERSION) && (IPVERSION == 4)
73u_int in_cksum_hdr(const struct ip *ip);
74#endif
75u_short	in_addword(u_short sum, u_short b);
76u_short	in_pseudo(u_int sum, u_int b, u_int c);
77u_short	in_cksum_skip(struct mbuf *m, int len, int skip);
78#endif
79
80#endif /* _MACHINE_IN_CKSUM_H_ */
81