xref: /openbmc/linux/include/net/ip6_checksum.h (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1*1da177e4SLinus Torvalds /*
2*1da177e4SLinus Torvalds  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3*1da177e4SLinus Torvalds  *		operating system.  INET is implemented using the  BSD Socket
4*1da177e4SLinus Torvalds  *		interface as the means of communication with the user level.
5*1da177e4SLinus Torvalds  *
6*1da177e4SLinus Torvalds  *		Checksumming functions for IPv6
7*1da177e4SLinus Torvalds  *
8*1da177e4SLinus Torvalds  * Authors:	Jorge Cwik, <jorge@laser.satlink.net>
9*1da177e4SLinus Torvalds  *		Arnt Gulbrandsen, <agulbra@nvg.unit.no>
10*1da177e4SLinus Torvalds  *		Borrows very liberally from tcp.c and ip.c, see those
11*1da177e4SLinus Torvalds  *		files for more names.
12*1da177e4SLinus Torvalds  *
13*1da177e4SLinus Torvalds  *		This program is free software; you can redistribute it and/or
14*1da177e4SLinus Torvalds  *		modify it under the terms of the GNU General Public License
15*1da177e4SLinus Torvalds  *		as published by the Free Software Foundation; either version
16*1da177e4SLinus Torvalds  *		2 of the License, or (at your option) any later version.
17*1da177e4SLinus Torvalds  */
18*1da177e4SLinus Torvalds 
19*1da177e4SLinus Torvalds /*
20*1da177e4SLinus Torvalds  *	Fixes:
21*1da177e4SLinus Torvalds  *
22*1da177e4SLinus Torvalds  *	Ralf Baechle			:	generic ipv6 checksum
23*1da177e4SLinus Torvalds  *	<ralf@waldorf-gmbh.de>
24*1da177e4SLinus Torvalds  */
25*1da177e4SLinus Torvalds 
26*1da177e4SLinus Torvalds #ifndef _CHECKSUM_IPV6_H
27*1da177e4SLinus Torvalds #define _CHECKSUM_IPV6_H
28*1da177e4SLinus Torvalds 
29*1da177e4SLinus Torvalds #include <asm/types.h>
30*1da177e4SLinus Torvalds #include <asm/byteorder.h>
31*1da177e4SLinus Torvalds #include <net/ip.h>
32*1da177e4SLinus Torvalds #include <asm/checksum.h>
33*1da177e4SLinus Torvalds #include <linux/in6.h>
34*1da177e4SLinus Torvalds 
35*1da177e4SLinus Torvalds #ifndef _HAVE_ARCH_IPV6_CSUM
36*1da177e4SLinus Torvalds 
37*1da177e4SLinus Torvalds static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
38*1da177e4SLinus Torvalds 						     struct in6_addr *daddr,
39*1da177e4SLinus Torvalds 						     __u16 len,
40*1da177e4SLinus Torvalds 						     unsigned short proto,
41*1da177e4SLinus Torvalds 						     unsigned int csum)
42*1da177e4SLinus Torvalds {
43*1da177e4SLinus Torvalds 
44*1da177e4SLinus Torvalds 	int carry;
45*1da177e4SLinus Torvalds 	__u32 ulen;
46*1da177e4SLinus Torvalds 	__u32 uproto;
47*1da177e4SLinus Torvalds 
48*1da177e4SLinus Torvalds 	csum += saddr->s6_addr32[0];
49*1da177e4SLinus Torvalds 	carry = (csum < saddr->s6_addr32[0]);
50*1da177e4SLinus Torvalds 	csum += carry;
51*1da177e4SLinus Torvalds 
52*1da177e4SLinus Torvalds 	csum += saddr->s6_addr32[1];
53*1da177e4SLinus Torvalds 	carry = (csum < saddr->s6_addr32[1]);
54*1da177e4SLinus Torvalds 	csum += carry;
55*1da177e4SLinus Torvalds 
56*1da177e4SLinus Torvalds 	csum += saddr->s6_addr32[2];
57*1da177e4SLinus Torvalds 	carry = (csum < saddr->s6_addr32[2]);
58*1da177e4SLinus Torvalds 	csum += carry;
59*1da177e4SLinus Torvalds 
60*1da177e4SLinus Torvalds 	csum += saddr->s6_addr32[3];
61*1da177e4SLinus Torvalds 	carry = (csum < saddr->s6_addr32[3]);
62*1da177e4SLinus Torvalds 	csum += carry;
63*1da177e4SLinus Torvalds 
64*1da177e4SLinus Torvalds 	csum += daddr->s6_addr32[0];
65*1da177e4SLinus Torvalds 	carry = (csum < daddr->s6_addr32[0]);
66*1da177e4SLinus Torvalds 	csum += carry;
67*1da177e4SLinus Torvalds 
68*1da177e4SLinus Torvalds 	csum += daddr->s6_addr32[1];
69*1da177e4SLinus Torvalds 	carry = (csum < daddr->s6_addr32[1]);
70*1da177e4SLinus Torvalds 	csum += carry;
71*1da177e4SLinus Torvalds 
72*1da177e4SLinus Torvalds 	csum += daddr->s6_addr32[2];
73*1da177e4SLinus Torvalds 	carry = (csum < daddr->s6_addr32[2]);
74*1da177e4SLinus Torvalds 	csum += carry;
75*1da177e4SLinus Torvalds 
76*1da177e4SLinus Torvalds 	csum += daddr->s6_addr32[3];
77*1da177e4SLinus Torvalds 	carry = (csum < daddr->s6_addr32[3]);
78*1da177e4SLinus Torvalds 	csum += carry;
79*1da177e4SLinus Torvalds 
80*1da177e4SLinus Torvalds 	ulen = htonl((__u32) len);
81*1da177e4SLinus Torvalds 	csum += ulen;
82*1da177e4SLinus Torvalds 	carry = (csum < ulen);
83*1da177e4SLinus Torvalds 	csum += carry;
84*1da177e4SLinus Torvalds 
85*1da177e4SLinus Torvalds 	uproto = htonl(proto);
86*1da177e4SLinus Torvalds 	csum += uproto;
87*1da177e4SLinus Torvalds 	carry = (csum < uproto);
88*1da177e4SLinus Torvalds 	csum += carry;
89*1da177e4SLinus Torvalds 
90*1da177e4SLinus Torvalds 	return csum_fold(csum);
91*1da177e4SLinus Torvalds }
92*1da177e4SLinus Torvalds 
93*1da177e4SLinus Torvalds #endif
94*1da177e4SLinus Torvalds #endif
95