LXR linux/net/ipv6/xfrm6

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * xfrm6_input.c: based on net/ipv4/xfrm4_input.c
   4 *
   5 * Authors:
   6 *      Mitsuru KANDA @USAGI
   7 *      Kazunori MIYAZAWA @USAGI
   8 *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9 *      YOSHIFUJI Hideaki @USAGI
  10 *              IPv6 support
  11 */
  12
  13#include <linux/module.h>
  14#include <linux/string.h>
  15#include <linux/netfilter.h>
  16#include <linux/netfilter_ipv6.h>
  17#include <net/ipv6.h>
  18#include <net/xfrm.h>
  19
  20int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb)
  21{
  22        return xfrm6_extract_header(skb);
  23}
  24
  25int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi,
  26                  struct ip6_tnl *t)
  27{
  28        XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
  29        XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
  30        XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
  31        return xfrm_input(skb, nexthdr, spi, 0);
  32}
  33EXPORT_SYMBOL(xfrm6_rcv_spi);
  34
  35static int xfrm6_transport_finish2(struct net *net, struct sock *sk,
  36                                   struct sk_buff *skb)
  37{
  38        if (xfrm_trans_queue(skb, ip6_rcv_finish))
  39                __kfree_skb(skb);
  40        return -1;
  41}
  42
  43int xfrm6_transport_finish(struct sk_buff *skb, int async)
  44{
  45        struct xfrm_offload *xo = xfrm_offload(skb);
  46        int nhlen = skb->data - skb_network_header(skb);
  47
  48        skb_network_header(skb)[IP6CB(skb)->nhoff] =
  49                XFRM_MODE_SKB_CB(skb)->protocol;
  50
  51#ifndef CONFIG_NETFILTER
  52        if (!async)
  53                return 1;
  54#endif
  55
  56        __skb_push(skb, nhlen);
  57        ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
  58        skb_postpush_rcsum(skb, skb_network_header(skb), nhlen);
  59
  60        if (xo && (xo->flags & XFRM_GRO)) {
  61                skb_mac_header_rebuild(skb);
  62                return -1;
  63        }
  64
  65        NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
  66                dev_net(skb->dev), NULL, skb, skb->dev, NULL,
  67                xfrm6_transport_finish2);
  68        return -1;
  69}
  70
  71int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t)
  72{
  73        return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
  74                             0, t);
  75}
  76EXPORT_SYMBOL(xfrm6_rcv_tnl);
  77
  78int xfrm6_rcv(struct sk_buff *skb)
  79{
  80        return xfrm6_rcv_tnl(skb, NULL);
  81}
  82EXPORT_SYMBOL(xfrm6_rcv);
  83int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
  84                     xfrm_address_t *saddr, u8 proto)
  85{
  86        struct net *net = dev_net(skb->dev);
  87        struct xfrm_state *x = NULL;
  88        int i = 0;
  89
  90        if (secpath_set(skb)) {
  91                XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
  92                goto drop;
  93        }
  94
  95        if (1 + skb->sp->len == XFRM_MAX_DEPTH) {
  96                XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
  97                goto drop;
  98        }
  99
 100        for (i = 0; i < 3; i++) {
 101                xfrm_address_t *dst, *src;
 102
 103                switch (i) {
 104                case 0:
 105                        dst = daddr;
 106                        src = saddr;
 107                        break;
 108                case 1:
 109                        /* lookup state with wild-card source address */
 110                        dst = daddr;
 111                        src = (xfrm_address_t *)&in6addr_any;
 112                        break;
 113                default:
 114                        /* lookup state with wild-card addresses */
 115                        dst = (xfrm_address_t *)&in6addr_any;
 116                        src = (xfrm_address_t *)&in6addr_any;
 117                        break;
 118                }
 119
 120                x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6);
 121                if (!x)
 122                        continue;
 123
 124                spin_lock(&x->lock);
 125
 126                if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
 127                    likely(x->km.state == XFRM_STATE_VALID) &&
 128                    !xfrm_state_check_expire(x)) {
 129                        spin_unlock(&x->lock);
 130                        if (x->type->input(x, skb) > 0) {
 131                                /* found a valid state */
 132                                break;
 133                        }
 134                } else
 135                        spin_unlock(&x->lock);
 136
 137                xfrm_state_put(x);
 138                x = NULL;
 139        }
 140
 141        if (!x) {
 142                XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 143                xfrm_audit_state_notfound_simple(skb, AF_INET6);
 144                goto drop;
 145        }
 146
 147        skb->sp->xvec[skb->sp->len++] = x;
 148
 149        spin_lock(&x->lock);
 150
 151        x->curlft.bytes += skb->len;
 152        x->curlft.packets++;
 153
 154        spin_unlock(&x->lock);
 155
 156        return 1;
 157
 158drop:
 159        return -1;
 160}
 161EXPORT_SYMBOL(xfrm6_input_addr);
 162