1*0f4c859eSApple OSS Distributions /*
2*0f4c859eSApple OSS Distributions * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
3*0f4c859eSApple OSS Distributions *
4*0f4c859eSApple OSS Distributions * @APPLE_LICENSE_HEADER_START@
5*0f4c859eSApple OSS Distributions *
6*0f4c859eSApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code
7*0f4c859eSApple OSS Distributions * as defined in and that are subject to the Apple Public Source License
8*0f4c859eSApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in
9*0f4c859eSApple OSS Distributions * compliance with the License. Please obtain a copy of the License at
10*0f4c859eSApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this
11*0f4c859eSApple OSS Distributions * file.
12*0f4c859eSApple OSS Distributions *
13*0f4c859eSApple OSS Distributions * The Original Code and all software distributed under the License are
14*0f4c859eSApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15*0f4c859eSApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16*0f4c859eSApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17*0f4c859eSApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18*0f4c859eSApple OSS Distributions * Please see the License for the specific language governing rights and
19*0f4c859eSApple OSS Distributions * limitations under the License.
20*0f4c859eSApple OSS Distributions *
21*0f4c859eSApple OSS Distributions * @APPLE_LICENSE_HEADER_END@
22*0f4c859eSApple OSS Distributions */
23*0f4c859eSApple OSS Distributions
24*0f4c859eSApple OSS Distributions /*
25*0f4c859eSApple OSS Distributions * Copyright (c) 1988, 1992, 1993
26*0f4c859eSApple OSS Distributions * The Regents of the University of California. All rights reserved.
27*0f4c859eSApple OSS Distributions *
28*0f4c859eSApple OSS Distributions * @(#)in_cksum.c 8.1 (Berkeley) 6/10/93
29*0f4c859eSApple OSS Distributions */
30*0f4c859eSApple OSS Distributions
31*0f4c859eSApple OSS Distributions #include <sys/param.h>
32*0f4c859eSApple OSS Distributions #include "in_cksum.h"
33*0f4c859eSApple OSS Distributions
34*0f4c859eSApple OSS Distributions typedef union {
35*0f4c859eSApple OSS Distributions char c[2];
36*0f4c859eSApple OSS Distributions u_short s;
37*0f4c859eSApple OSS Distributions } short_union_t;
38*0f4c859eSApple OSS Distributions
39*0f4c859eSApple OSS Distributions typedef union {
40*0f4c859eSApple OSS Distributions u_short s[2];
41*0f4c859eSApple OSS Distributions long l;
42*0f4c859eSApple OSS Distributions } long_union_t;
43*0f4c859eSApple OSS Distributions
44*0f4c859eSApple OSS Distributions static __inline__ void
reduce(int * sum)45*0f4c859eSApple OSS Distributions reduce(int * sum)
46*0f4c859eSApple OSS Distributions {
47*0f4c859eSApple OSS Distributions long_union_t l_util;
48*0f4c859eSApple OSS Distributions
49*0f4c859eSApple OSS Distributions l_util.l = *sum;
50*0f4c859eSApple OSS Distributions *sum = l_util.s[0] + l_util.s[1];
51*0f4c859eSApple OSS Distributions if (*sum > 65535) {
52*0f4c859eSApple OSS Distributions *sum -= 65535;
53*0f4c859eSApple OSS Distributions }
54*0f4c859eSApple OSS Distributions return;
55*0f4c859eSApple OSS Distributions }
56*0f4c859eSApple OSS Distributions
57*0f4c859eSApple OSS Distributions
58*0f4c859eSApple OSS Distributions #include <stdio.h>
59*0f4c859eSApple OSS Distributions
60*0f4c859eSApple OSS Distributions unsigned short
in_cksum(void * pkt,int len)61*0f4c859eSApple OSS Distributions in_cksum(void * pkt, int len)
62*0f4c859eSApple OSS Distributions {
63*0f4c859eSApple OSS Distributions u_short * w;
64*0f4c859eSApple OSS Distributions int sum = 0;
65*0f4c859eSApple OSS Distributions
66*0f4c859eSApple OSS Distributions w = (u_short *)pkt;
67*0f4c859eSApple OSS Distributions while ((len -= 32) >= 0) {
68*0f4c859eSApple OSS Distributions sum += w[0]; sum += w[1];
69*0f4c859eSApple OSS Distributions sum += w[2]; sum += w[3];
70*0f4c859eSApple OSS Distributions sum += w[4]; sum += w[5];
71*0f4c859eSApple OSS Distributions sum += w[6]; sum += w[7];
72*0f4c859eSApple OSS Distributions sum += w[8]; sum += w[9];
73*0f4c859eSApple OSS Distributions sum += w[10]; sum += w[11];
74*0f4c859eSApple OSS Distributions sum += w[12]; sum += w[13];
75*0f4c859eSApple OSS Distributions sum += w[14]; sum += w[15];
76*0f4c859eSApple OSS Distributions w += 16;
77*0f4c859eSApple OSS Distributions }
78*0f4c859eSApple OSS Distributions len += 32;
79*0f4c859eSApple OSS Distributions while ((len -= 8) >= 0) {
80*0f4c859eSApple OSS Distributions sum += w[0]; sum += w[1];
81*0f4c859eSApple OSS Distributions sum += w[2]; sum += w[3];
82*0f4c859eSApple OSS Distributions w += 4;
83*0f4c859eSApple OSS Distributions }
84*0f4c859eSApple OSS Distributions len += 8;
85*0f4c859eSApple OSS Distributions if (len) {
86*0f4c859eSApple OSS Distributions reduce(&sum);
87*0f4c859eSApple OSS Distributions while ((len -= 2) >= 0) {
88*0f4c859eSApple OSS Distributions sum += *w++;
89*0f4c859eSApple OSS Distributions }
90*0f4c859eSApple OSS Distributions }
91*0f4c859eSApple OSS Distributions if (len == -1) { /* odd-length packet */
92*0f4c859eSApple OSS Distributions short_union_t s_util;
93*0f4c859eSApple OSS Distributions
94*0f4c859eSApple OSS Distributions s_util.s = 0;
95*0f4c859eSApple OSS Distributions s_util.c[0] = *((char *)w);
96*0f4c859eSApple OSS Distributions s_util.c[1] = 0;
97*0f4c859eSApple OSS Distributions sum += s_util.s;
98*0f4c859eSApple OSS Distributions }
99*0f4c859eSApple OSS Distributions reduce(&sum);
100*0f4c859eSApple OSS Distributions return ~sum & 0xffff;
101*0f4c859eSApple OSS Distributions }
102