in_cksum.h revision 235941
115291Swollman/*- 215291Swollman * Copyright (c) 1990 The Regents of the University of California. 315291Swollman * All rights reserved. 415291Swollman * 515291Swollman * Redistribution and use in source and binary forms, with or without 615291Swollman * modification, are permitted provided that the following conditions 715291Swollman * are met: 815291Swollman * 1. Redistributions of source code must retain the above copyright 915291Swollman * notice, this list of conditions and the following disclaimer. 1015291Swollman * 2. Redistributions in binary form must reproduce the above copyright 1115291Swollman * notice, this list of conditions and the following disclaimer in the 1215291Swollman * documentation and/or other materials provided with the distribution. 1315291Swollman * 4. Neither the name of the University nor the names of its contributors 1415291Swollman * may be used to endorse or promote products derived from this software 1515291Swollman * without specific prior written permission. 1615291Swollman * 1715291Swollman * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 1815291Swollman * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1915291Swollman * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2015291Swollman * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2115291Swollman * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2215291Swollman * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2315291Swollman * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2415291Swollman * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2515291Swollman * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2615291Swollman * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2715291Swollman * SUCH DAMAGE. 2815291Swollman * 2915291Swollman * from tahoe: in_cksum.c 1.2 86/01/05 3015291Swollman * from: @(#)in_cksum.c 1.3 (Berkeley) 1/19/91 3115291Swollman * from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp 3250477Speter * $FreeBSD: head/sys/i386/include/in_cksum.h 235941 2012-05-24 22:00:48Z bz $ 3315291Swollman */ 3415291Swollman 3515291Swollman#ifndef _MACHINE_IN_CKSUM_H_ 3615291Swollman#define _MACHINE_IN_CKSUM_H_ 1 3715291Swollman 38143063Sjoerg#ifndef _SYS_CDEFS_H_ 39143063Sjoerg#error this file needs sys/cdefs.h as a prerequisite 40143063Sjoerg#endif 41143063Sjoerg 4269133Salfred/* 4369133Salfred * MP safe (alfred) 4469133Salfred */ 4569133Salfred 4615291Swollman#include <sys/cdefs.h> 4715291Swollman 4860104Sjlemon#define in_cksum(m, len) in_cksum_skip(m, len, 0) 4960104Sjlemon 5015291Swollman/* 5115291Swollman * It it useful to have an Internet checksum routine which is inlineable 5215291Swollman * and optimized specifically for the task of computing IP header checksums 5315291Swollman * in the normal case (where there are no options and the header length is 5415291Swollman * therefore always exactly five 32-bit words. 5515291Swollman */ 56143063Sjoerg#if defined(__GNUCLIKE_ASM) && !defined(__INTEL_COMPILER) 57235941Sbz#if defined(IPVERSION) && (IPVERSION == 4) 5815291Swollmanstatic __inline u_int 5915291Swollmanin_cksum_hdr(const struct ip *ip) 6015291Swollman{ 61194111Sed u_int sum = 0; 6215291Swollman 63194111Sed __asm( 64134300Sobrien "addl %1, %0\n" 65134300Sobrien "adcl %2, %0\n" 66134300Sobrien "adcl %3, %0\n" 67134300Sobrien "adcl %4, %0\n" 68134300Sobrien "adcl %5, %0\n" 69134300Sobrien "adcl $0, %0" 70134300Sobrien : "+r" (sum) 71134300Sobrien : "g" (((const u_int32_t *)ip)[0]), 72134300Sobrien "g" (((const u_int32_t *)ip)[1]), 73134300Sobrien "g" (((const u_int32_t *)ip)[2]), 74134300Sobrien "g" (((const u_int32_t *)ip)[3]), 75134300Sobrien "g" (((const u_int32_t *)ip)[4]) 76194111Sed : "cc" 77134300Sobrien ); 7815291Swollman sum = (sum & 0xffff) + (sum >> 16); 7915291Swollman if (sum > 0xffff) 8015291Swollman sum -= 0xffff; 8115291Swollman 8215291Swollman return ~sum & 0xffff; 8315291Swollman} 8415884Swollman 8515884Swollmanstatic __inline void 8615884Swollmanin_cksum_update(struct ip *ip) 8715884Swollman{ 8815884Swollman int __tmpsum; 8915884Swollman __tmpsum = (int)ntohs(ip->ip_sum) + 256; 9015884Swollman ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); 9115884Swollman} 92235941Sbz#endif 9315884Swollman 9458698Sjlemonstatic __inline u_short 9558698Sjlemonin_addword(u_short sum, u_short b) 9658698Sjlemon{ 97194111Sed __asm( 98172835Sbz "addw %1, %0\n" 99172835Sbz "adcw $0, %0" 100172835Sbz : "+r" (sum) 101194111Sed : "g" (b) 102194111Sed : "cc" 103172835Sbz ); 10458698Sjlemon return (sum); 10558698Sjlemon} 10658698Sjlemon 10758698Sjlemonstatic __inline u_short 10858698Sjlemonin_pseudo(u_int sum, u_int b, u_int c) 10958698Sjlemon{ 110194111Sed __asm( 111172835Sbz "addl %1, %0\n" 112172835Sbz "adcl %2, %0\n" 113172835Sbz "adcl $0, %0" 114172835Sbz : "+r" (sum) 115172835Sbz : "g" (b), 116172835Sbz "g" (c) 117194111Sed : "cc" 118172835Sbz ); 11958698Sjlemon sum = (sum & 0xffff) + (sum >> 16); 12058698Sjlemon if (sum > 0xffff) 12158698Sjlemon sum -= 0xffff; 12258698Sjlemon return (sum); 12358698Sjlemon} 12458698Sjlemon 12515291Swollman#else 126235941Sbz#if defined(IPVERSION) && (IPVERSION == 4) 12715884Swollman#define in_cksum_update(ip) \ 12815884Swollman do { \ 12915884Swollman int __tmpsum; \ 13015884Swollman __tmpsum = (int)ntohs(ip->ip_sum) + 256; \ 13115884Swollman ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); \ 13215884Swollman } while(0) 13315884Swollman 13415291Swollman#endif 135235941Sbz#endif 13615291Swollman 13755205Speter#ifdef _KERNEL 138143063Sjoerg#if !defined(__GNUCLIKE_ASM) || defined(__INTEL_COMPILER) 139235941Sbz#if defined(IPVERSION) && (IPVERSION == 4) 140126891Strhodesu_int in_cksum_hdr(const struct ip *ip); 141235941Sbz#endif 142126891Strhodesu_short in_addword(u_short sum, u_short b); 143126891Strhodesu_short in_pseudo(u_int sum, u_int b, u_int c); 144126891Strhodes#endif 145126891Strhodesu_short in_cksum_skip(struct mbuf *m, int len, int skip); 14655205Speter#endif /* _KERNEL */ 14728270Swollman 14815291Swollman#endif /* _MACHINE_IN_CKSUM_H_ */ 149