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 * 4. 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 * $FreeBSD$ 33 */ 34 35 #ifndef _MACHINE_IN_CKSUM_H_ 36 #define _MACHINE_IN_CKSUM_H_ 1 37 38 #ifndef _SYS_CDEFS_H_ 39 #error this file needs sys/cdefs.h as a prerequisite 40 #endif 41 42 #include <sys/cdefs.h> 43 44 #define in_cksum(m, len) in_cksum_skip(m, len, 0) 45 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 54 static __inline void 55 in_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 73 #ifdef _KERNEL 74 u_int in_cksum_hdr(const struct ip *ip); 75 u_short in_addword(u_short sum, u_short b); 76 u_short in_pseudo(u_int sum, u_int b, u_int c); 77 u_short in_cksum_skip(struct mbuf *m, int len, int skip); 78 #endif 79 80 #endif /* _MACHINE_IN_CKSUM_H_ */ 81