root/include/net/ip6_checksum.h

INCLUDED FROM

DEFINITIONS

1. ip6_compute_pseudo
2. ip6_gro_compute_pseudo
3. tcp_v6_check
4. __tcp_v6_send_check
5. tcp_v6_send_check
6. udp_v6_check

/*
 * INET         An implementation of the TCP/IP protocol suite for the LINUX
 *              operating system.  INET is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              Checksumming functions for IPv6
 *
 * Authors:     Jorge Cwik, <jorge@laser.satlink.net>
 *              Arnt Gulbrandsen, <agulbra@nvg.unit.no>
 *              Borrows very liberally from tcp.c and ip.c, see those
 *              files for more names.
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 */

/*
 *      Fixes:
 *
 *      Ralf Baechle                    :       generic ipv6 checksum
 *      <ralf@waldorf-gmbh.de>
 */

#ifndef _CHECKSUM_IPV6_H
#define _CHECKSUM_IPV6_H

#include <asm/types.h>
#include <asm/byteorder.h>
#include <net/ip.h>
#include <asm/checksum.h>
#include <linux/in6.h>
#include <linux/tcp.h>
#include <linux/ipv6.h>

#ifndef _HAVE_ARCH_IPV6_CSUM
__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
                        const struct in6_addr *daddr,
                        __u32 len, unsigned short proto,
                        __wsum csum);
#endif

static inline __wsum ip6_compute_pseudo(struct sk_buff *skb, int proto)
{
        return ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
                                            &ipv6_hdr(skb)->daddr,
                                            skb->len, proto, 0));
}

static inline __wsum ip6_gro_compute_pseudo(struct sk_buff *skb, int proto)
{
        const struct ipv6hdr *iph = skb_gro_network_header(skb);

        return ~csum_unfold(csum_ipv6_magic(&iph->saddr, &iph->daddr,
                                            skb_gro_len(skb), proto, 0));
}

static __inline__ __sum16 tcp_v6_check(int len,
                                   const struct in6_addr *saddr,
                                   const struct in6_addr *daddr,
                                   __wsum base)
{
        return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
}

static inline void __tcp_v6_send_check(struct sk_buff *skb,
                                       const struct in6_addr *saddr,
                                       const struct in6_addr *daddr)
{
        struct tcphdr *th = tcp_hdr(skb);

        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0);
                skb->csum_start = skb_transport_header(skb) - skb->head;
                skb->csum_offset = offsetof(struct tcphdr, check);
        } else {
                th->check = tcp_v6_check(skb->len, saddr, daddr,
                                         csum_partial(th, th->doff << 2,
                                                      skb->csum));
        }
}

#if IS_ENABLED(CONFIG_IPV6)
static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
{
        struct ipv6_pinfo *np = inet6_sk(sk);

        __tcp_v6_send_check(skb, &np->saddr, &sk->sk_v6_daddr);
}
#endif

static inline __sum16 udp_v6_check(int len,
                                   const struct in6_addr *saddr,
                                   const struct in6_addr *daddr,
                                   __wsum base)
{
        return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base);
}

void udp6_set_csum(bool nocheck, struct sk_buff *skb,
                   const struct in6_addr *saddr,
                   const struct in6_addr *daddr, int len);

int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto);
#endif