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 #include <linux/tcp.h> 35 #include <linux/ipv6.h> 36 37 #ifndef _HAVE_ARCH_IPV6_CSUM 38 __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 39 const struct in6_addr *daddr, 40 __u32 len, unsigned short proto, 41 __wsum csum); 42 #endif 43 44 static inline __wsum ip6_compute_pseudo(struct sk_buff *skb, int proto) 45 { 46 return ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 47 &ipv6_hdr(skb)->daddr, 48 skb->len, proto, 0)); 49 } 50 51 static __inline__ __sum16 tcp_v6_check(int len, 52 const struct in6_addr *saddr, 53 const struct in6_addr *daddr, 54 __wsum base) 55 { 56 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); 57 } 58 59 static inline void __tcp_v6_send_check(struct sk_buff *skb, 60 const struct in6_addr *saddr, 61 const struct in6_addr *daddr) 62 { 63 struct tcphdr *th = tcp_hdr(skb); 64 65 if (skb->ip_summed == CHECKSUM_PARTIAL) { 66 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0); 67 skb->csum_start = skb_transport_header(skb) - skb->head; 68 skb->csum_offset = offsetof(struct tcphdr, check); 69 } else { 70 th->check = tcp_v6_check(skb->len, saddr, daddr, 71 csum_partial(th, th->doff << 2, 72 skb->csum)); 73 } 74 } 75 76 #if IS_ENABLED(CONFIG_IPV6) 77 static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb) 78 { 79 struct ipv6_pinfo *np = inet6_sk(sk); 80 81 __tcp_v6_send_check(skb, &np->saddr, &sk->sk_v6_daddr); 82 } 83 #endif 84 85 static inline __sum16 udp_v6_check(int len, 86 const struct in6_addr *saddr, 87 const struct in6_addr *daddr, 88 __wsum base) 89 { 90 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base); 91 } 92 93 void udp6_set_csum(bool nocheck, struct sk_buff *skb, 94 const struct in6_addr *saddr, 95 const struct in6_addr *daddr, int len); 96 97 int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto); 98 #endif 99