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, __u8 proto, __wsum csum);
41#endif
42
43static inline __wsum ip6_compute_pseudo(struct sk_buff *skb, int proto)
44{
45 return ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
46 &ipv6_hdr(skb)->daddr,
47 skb->len, proto, 0));
48}
49
50static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto)
51{
52 const struct ipv6hdr *iph = skb_gro_network_header(skb);
53
54 return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
55 skb_gro_len(skb), proto, 0));
56}
57
58static __inline__ __sum16 tcp_v6_check(int len,
59 const struct in6_addr *saddr,
60 const struct in6_addr *daddr,
61 __wsum base)
62{
63 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
64}
65
66static inline void __tcp_v6_send_check(struct sk_buff *skb,
67 const struct in6_addr *saddr,
68 const struct in6_addr *daddr)
69{
70 struct tcphdr *th = tcp_hdr(skb);
71
72 if (skb->ip_summed == CHECKSUM_PARTIAL) {
73 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0);
74 skb->csum_start = skb_transport_header(skb) - skb->head;
75 skb->csum_offset = offsetof(struct tcphdr, check);
76 } else {
77 th->check = tcp_v6_check(skb->len, saddr, daddr,
78 csum_partial(th, th->doff << 2,
79 skb->csum));
80 }
81}
82
83#if IS_ENABLED(CONFIG_IPV6)
84static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
85{
86 struct ipv6_pinfo *np = inet6_sk(sk);
87
88 __tcp_v6_send_check(skb, &np->saddr, &sk->sk_v6_daddr);
89}
90#endif
91
92static inline __sum16 udp_v6_check(int len,
93 const struct in6_addr *saddr,
94 const struct in6_addr *daddr,
95 __wsum base)
96{
97 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base);
98}
99
100void udp6_set_csum(bool nocheck, struct sk_buff *skb,
101 const struct in6_addr *saddr,
102 const struct in6_addr *daddr, int len);
103
104int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto);
105#endif
106