1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Checksumming functions for IPv6
7 *
8 * Authors: Jorge Cwik, <jorge@laser.satlink.net>
9 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
10 * Borrows very liberally from tcp.c and ip.c, see those
11 * files for more names.
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18
19 /*
20 * Fixes:
21 *
22 * Ralf Baechle : generic ipv6 checksum
23 * <ralf@waldorf-gmbh.de>
24 */
25
26 #ifndef _CHECKSUM_IPV6_H
27 #define _CHECKSUM_IPV6_H
28
29 #include <asm/types.h>
30 #include <asm/byteorder.h>
31 #include <net/ip.h>
32 #include <asm/checksum.h>
33 #include <linux/in6.h>
34
35 #ifndef _HAVE_ARCH_IPV6_CSUM
36
csum_ipv6_magic(const struct in6_addr * saddr,const struct in6_addr * daddr,__u32 len,unsigned short proto,__wsum csum)37 static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
38 const struct in6_addr *daddr,
39 __u32 len, unsigned short proto,
40 __wsum csum)
41 {
42
43 int carry;
44 __u32 ulen;
45 __u32 uproto;
46 __u32 sum = (__force u32)csum;
47
48 sum += (__force u32)saddr->s6_addr32[0];
49 carry = (sum < (__force u32)saddr->s6_addr32[0]);
50 sum += carry;
51
52 sum += (__force u32)saddr->s6_addr32[1];
53 carry = (sum < (__force u32)saddr->s6_addr32[1]);
54 sum += carry;
55
56 sum += (__force u32)saddr->s6_addr32[2];
57 carry = (sum < (__force u32)saddr->s6_addr32[2]);
58 sum += carry;
59
60 sum += (__force u32)saddr->s6_addr32[3];
61 carry = (sum < (__force u32)saddr->s6_addr32[3]);
62 sum += carry;
63
64 sum += (__force u32)daddr->s6_addr32[0];
65 carry = (sum < (__force u32)daddr->s6_addr32[0]);
66 sum += carry;
67
68 sum += (__force u32)daddr->s6_addr32[1];
69 carry = (sum < (__force u32)daddr->s6_addr32[1]);
70 sum += carry;
71
72 sum += (__force u32)daddr->s6_addr32[2];
73 carry = (sum < (__force u32)daddr->s6_addr32[2]);
74 sum += carry;
75
76 sum += (__force u32)daddr->s6_addr32[3];
77 carry = (sum < (__force u32)daddr->s6_addr32[3]);
78 sum += carry;
79
80 ulen = (__force u32)htonl((__u32) len);
81 sum += ulen;
82 carry = (sum < ulen);
83 sum += carry;
84
85 uproto = (__force u32)htonl(proto);
86 sum += uproto;
87 carry = (sum < uproto);
88 sum += carry;
89
90 return csum_fold((__force __wsum)sum);
91 }
92
93 #endif
94 #endif
95