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Diffstat (limited to 'c/src/exec/libnetworking/machine/in_cksum.h')
| -rw-r--r-- | c/src/exec/libnetworking/machine/in_cksum.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/c/src/exec/libnetworking/machine/in_cksum.h b/c/src/exec/libnetworking/machine/in_cksum.h new file mode 100644 index 0000000000..15509b3888 --- /dev/null +++ b/c/src/exec/libnetworking/machine/in_cksum.h @@ -0,0 +1,118 @@ +/*- + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * from tahoe: in_cksum.c 1.2 86/01/05 + * from: @(#)in_cksum.c 1.3 (Berkeley) 1/19/91 + * from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp + * $Id$ + */ + +#ifndef _MACHINE_IN_CKSUM_H_ +#define _MACHINE_IN_CKSUM_H_ 1 + +#include <sys/cdefs.h> + +/* + * It it useful to have an Internet checksum routine which is inlineable + * and optimized specifically for the task of computing IP header checksums + * in the normal case (where there are no options and the header length is + * therefore always exactly five 32-bit words. + */ +#if (defined(__GNUC__) && defined(__i386__)) +static __inline u_int +in_cksum_hdr(const struct ip *ip) +{ + register u_int sum = 0; + +#define ADD(n) __asm("addl " #n "(%2), %0" : "=r" (sum) : "0" (sum), "r" (ip)) +#define ADDC(n) __asm("adcl " #n "(%2), %0" : "=r" (sum) : "0" (sum), "r" (ip)) +#define MOP __asm("adcl $0, %0" : "=r" (sum) : "0" (sum)) + + ADD(0); + ADDC(4); + ADDC(8); + ADDC(12); + ADDC(16); + MOP; + sum = (sum & 0xffff) + (sum >> 16); + if (sum > 0xffff) + sum -= 0xffff; + + return ~sum & 0xffff; +} + +static __inline void +in_cksum_update(struct ip *ip) +{ + int __tmpsum; + __tmpsum = (int)ntohs(ip->ip_sum) + 256; + ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); +} + +#elif (defined(__GNUC__) && (defined(__mc68000__) || defined(__m68k__))) + +static __inline__ u_int +in_cksum_hdr(const struct ip *ip) +{ + register u_int *ap = (u_int *)ip; + register u_int sum = *ap++; + register u_int tmp; + + __asm__("addl %2@+,%0\n\t" + "movel %2@+,%1\n\t" + "addxl %1,%0\n\t" + "movel %2@+,%1\n\t" + "addxl %1,%0\n\t" + "movel %2@,%1\n\t" + "addxl %1,%0\n\t" + "moveq #0,%1\n\t" + "addxl %1,%0\n" : + "=d" (sum), "=d" (tmp), "=a" (ap) : + "0" (sum), "2" (ap)); + sum = (sum & 0xffff) + (sum >> 16); + if (sum > 0xffff) + sum -= 0xffff; + return ~sum & 0xffff; +} + +#else +u_int in_cksum_hdr __P((const struct ip *)); +#define in_cksum_update(ip) \ + do { \ + int __tmpsum; \ + __tmpsum = (int)ntohs(ip->ip_sum) + 256; \ + ip->ip_sum = htons(__tmpsum + (__tmpsum >> 16)); \ + } while(0) + +#endif + +#endif /* _MACHINE_IN_CKSUM_H_ */ |