| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
| 37 | static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, |
| 38 | struct in6_addr *daddr, |
| 39 | __u16 len, |
| 40 | unsigned short proto, |
| 41 | unsigned int csum) |
| 42 | { |
| 43 | |
| 44 | int carry; |
| 45 | __u32 ulen; |
| 46 | __u32 uproto; |
| 47 | |
| 48 | csum += saddr->s6_addr32[0]; |
| 49 | carry = (csum < saddr->s6_addr32[0]); |
| 50 | csum += carry; |
| 51 | |
| 52 | csum += saddr->s6_addr32[1]; |
| 53 | carry = (csum < saddr->s6_addr32[1]); |
| 54 | csum += carry; |
| 55 | |
| 56 | csum += saddr->s6_addr32[2]; |
| 57 | carry = (csum < saddr->s6_addr32[2]); |
| 58 | csum += carry; |
| 59 | |
| 60 | csum += saddr->s6_addr32[3]; |
| 61 | carry = (csum < saddr->s6_addr32[3]); |
| 62 | csum += carry; |
| 63 | |
| 64 | csum += daddr->s6_addr32[0]; |
| 65 | carry = (csum < daddr->s6_addr32[0]); |
| 66 | csum += carry; |
| 67 | |
| 68 | csum += daddr->s6_addr32[1]; |
| 69 | carry = (csum < daddr->s6_addr32[1]); |
| 70 | csum += carry; |
| 71 | |
| 72 | csum += daddr->s6_addr32[2]; |
| 73 | carry = (csum < daddr->s6_addr32[2]); |
| 74 | csum += carry; |
| 75 | |
| 76 | csum += daddr->s6_addr32[3]; |
| 77 | carry = (csum < daddr->s6_addr32[3]); |
| 78 | csum += carry; |
| 79 | |
| 80 | ulen = htonl((__u32) len); |
| 81 | csum += ulen; |
| 82 | carry = (csum < ulen); |
| 83 | csum += carry; |
| 84 | |
| 85 | uproto = htonl(proto); |
| 86 | csum += uproto; |
| 87 | carry = (csum < uproto); |
| 88 | csum += carry; |
| 89 | |
| 90 | return csum_fold(csum); |
| 91 | } |
| 92 | |
| 93 | #endif |
| 94 | #endif |