1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * from tahoe: in_cksum.c 1.2 86/01/05
32 * from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
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/*
43 * It it useful to have an Internet checksum routine which is inlineable
44 * and optimized specifically for the task of computing IP header checksums
45 * in the normal case (where there are no options and the header length is
46 * therefore always exactly five 32-bit words.
47 */
48#if defined(IPVERSION) && (IPVERSION == 4)
49static __inline u_int
50in_cksum_hdr(const struct ip *ip)
51{
52 u_int sum = 0;
53
54 __asm(
55 "addl %1, %0\n"
56 "adcl %2, %0\n"
57 "adcl %3, %0\n"
58 "adcl %4, %0\n"
59 "adcl %5, %0\n"
60 "adcl $0, %0"
61 : "+r" (sum)
62 : "g" (((const u_int32_t *)ip)[0]),
63 "g" (((const u_int32_t *)ip)[1]),
64 "g" (((const u_int32_t *)ip)[2]),
65 "g" (((const u_int32_t *)ip)[3]),
66 "g" (((const u_int32_t *)ip)[4])
67 : "cc"
68 );
69 sum = (sum & 0xffff) + (sum >> 16);
70 if (sum > 0xffff)
71 sum -= 0xffff;
72
73 return ~sum & 0xffff;
74}
75#endif
76
77static __inline u_short
78in_addword(u_short sum, u_short b)
79{
80 __asm(
81 "addw %1, %0\n"
82 "adcw $0, %0"
83 : "+r" (sum)
84 : "g" (b)
85 : "cc"
86 );
87 return (sum);
88}
89
90static __inline u_short
91in_pseudo(u_int sum, u_int b, u_int c)
92{
93 __asm(
94 "addl %1, %0\n"
95 "adcl %2, %0\n"
96 "adcl $0, %0"
97 : "+r" (sum)
98 : "g" (b),
99 "g" (c)
100 : "cc"
101 );
102 sum = (sum & 0xffff) + (sum >> 16);
103 if (sum > 0xffff)
104 sum -= 0xffff;
105 return (sum);
106}
107
108#ifdef _KERNEL
109
110#define HAVE_MD_IN_CKSUM
111
112u_short in_cksum_skip(struct mbuf *m, int len, int skip);
113#endif /* _KERNEL */
114
115#endif /* _MACHINE_IN_CKSUM_H_ */