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 __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto) 52 { 53 const struct ipv6hdr *iph = skb_gro_network_header(skb); 54 55 return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr, 56 skb_gro_len(skb), proto, 0)); 57 } 58 59 static __inline__ __sum16 tcp_v6_check(int len, 60 const struct in6_addr *saddr, 61 const struct in6_addr *daddr, 62 __wsum base) 63 { 64 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); 65 } 66 67 static inline void __tcp_v6_send_check(struct sk_buff *skb, 68 const struct in6_addr *saddr, 69 const struct in6_addr *daddr) 70 { 71 struct tcphdr *th = tcp_hdr(skb); 72 73 if (skb->ip_summed == CHECKSUM_PARTIAL) { 74 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0); 75 skb->csum_start = skb_transport_header(skb) - skb->head; 76 skb->csum_offset = offsetof(struct tcphdr, check); 77 } else { 78 th->check = tcp_v6_check(skb->len, saddr, daddr, 79 csum_partial(th, th->doff << 2, 80 skb->csum)); 81 } 82 } 83 84 #if IS_ENABLED(CONFIG_IPV6) 85 static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb) 86 { 87 struct ipv6_pinfo *np = inet6_sk(sk); 88 89 __tcp_v6_send_check(skb, &np->saddr, &sk->sk_v6_daddr); 90 } 91 #endif 92 93 static inline __sum16 udp_v6_check(int len, 94 const struct in6_addr *saddr, 95 const struct in6_addr *daddr, 96 __wsum base) 97 { 98 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base); 99 } 100 101 void udp6_set_csum(bool nocheck, struct sk_buff *skb, 102 const struct in6_addr *saddr, 103 const struct in6_addr *daddr, int len); 104 105 int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto); 106 #endif 107