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__ __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