in_cksum.h revision 66458
166458Sdfr/*-
266458Sdfr * Copyright (c) 1990 The Regents of the University of California.
366458Sdfr * All rights reserved.
466458Sdfr *
566458Sdfr * Redistribution and use in source and binary forms, with or without
666458Sdfr * modification, are permitted provided that the following conditions
766458Sdfr * are met:
866458Sdfr * 1. Redistributions of source code must retain the above copyright
966458Sdfr *    notice, this list of conditions and the following disclaimer.
1066458Sdfr * 2. Redistributions in binary form must reproduce the above copyright
1166458Sdfr *    notice, this list of conditions and the following disclaimer in the
1266458Sdfr *    documentation and/or other materials provided with the distribution.
1366458Sdfr * 3. All advertising materials mentioning features or use of this software
1466458Sdfr *    must display the following acknowledgement:
1566458Sdfr *	This product includes software developed by the University of
1666458Sdfr *	California, Berkeley and its contributors.
1766458Sdfr * 4. Neither the name of the University nor the names of its contributors
1866458Sdfr *    may be used to endorse or promote products derived from this software
1966458Sdfr *    without specific prior written permission.
2066458Sdfr *
2166458Sdfr * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2266458Sdfr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2366458Sdfr * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2466458Sdfr * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2566458Sdfr * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2666458Sdfr * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2766458Sdfr * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2866458Sdfr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2966458Sdfr * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
3066458Sdfr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3166458Sdfr * SUCH DAMAGE.
3266458Sdfr *
3366458Sdfr *	from tahoe:	in_cksum.c	1.2	86/01/05
3466458Sdfr *	from:		@(#)in_cksum.c	1.3 (Berkeley) 1/19/91
3566458Sdfr *	from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
3666458Sdfr * $FreeBSD: head/sys/ia64/include/in_cksum.h 66458 2000-09-29 13:46:07Z dfr $
3766458Sdfr */
3866458Sdfr
3966458Sdfr#ifndef _MACHINE_IN_CKSUM_H_
4066458Sdfr#define	_MACHINE_IN_CKSUM_H_	1
4166458Sdfr
4266458Sdfr#include <sys/cdefs.h>
4366458Sdfr
4466458Sdfr#define in_cksum(m, len)	in_cksum_skip(m, len, 0)
4566458Sdfr
4666458Sdfr/*
4766458Sdfr * It it useful to have an Internet checksum routine which is inlineable
4866458Sdfr * and optimized specifically for the task of computing IP header checksums
4966458Sdfr * in the normal case (where there are no options and the header length is
5066458Sdfr * therefore always exactly five 32-bit words.
5166458Sdfr */
5266458Sdfr#ifdef __GNUC__
5366458Sdfr
5466458Sdfrstatic __inline void
5566458Sdfrin_cksum_update(struct ip *ip)
5666458Sdfr{
5766458Sdfr	int __tmpsum;
5866458Sdfr	__tmpsum = (int)ntohs(ip->ip_sum) + 256;
5966458Sdfr	ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16));
6066458Sdfr}
6166458Sdfr
6266458Sdfr#else
6366458Sdfr
6466458Sdfr#define	in_cksum_update(ip) \
6566458Sdfr	do { \
6666458Sdfr		int __tmpsum; \
6766458Sdfr		__tmpsum = (int)ntohs(ip->ip_sum) + 256; \
6866458Sdfr		ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); \
6966458Sdfr	} while(0)
7066458Sdfr
7166458Sdfr#endif
7266458Sdfr
7366458Sdfr#ifdef _KERNEL
7466458Sdfru_int in_cksum_hdr(const struct ip *ip);
7566458Sdfru_short	in_addword(u_short sum, u_short b);
7666458Sdfru_short	in_pseudo(u_int sum, u_int b, u_int c);
7766458Sdfru_short	in_cksum_skip(struct mbuf *m, int len, int skip);
7866458Sdfr#endif
7966458Sdfr
8066458Sdfr#endif /* _MACHINE_IN_CKSUM_H_ */
81