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                skb_reset_transport_header(skb);
  63                return -1;
  64        }
  65
  66        NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
  67                dev_net(skb->dev), NULL, skb, skb->dev, NULL,
  68                xfrm6_transport_finish2);
  69        return -1;
  70}
  71
  72int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t)
  73{
  74        return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
  75                             0, t);
  76}
  77EXPORT_SYMBOL(xfrm6_rcv_tnl);
  78
  79int xfrm6_rcv(struct sk_buff *skb)
  80{
  81        return xfrm6_rcv_tnl(skb, NULL);
  82}
  83EXPORT_SYMBOL(xfrm6_rcv);
  84int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
  85                     xfrm_address_t *saddr, u8 proto)
  86{
  87        struct net *net = dev_net(skb->dev);
  88        struct xfrm_state *x = NULL;
  89        struct sec_path *sp;
  90        int i = 0;
  91
  92        sp = secpath_set(skb);
  93        if (!sp) {
  94                XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
  95                goto drop;
  96        }
  97
  98        if (1 + sp->len == XFRM_MAX_DEPTH) {
  99                XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 100                goto drop;
 101        }
 102
 103        for (i = 0; i < 3; i++) {
 104                xfrm_address_t *dst, *src;
 105
 106                switch (i) {
 107                case 0:
 108                        dst = daddr;
 109                        src = saddr;
 110                        break;
 111                case 1:
 112                        /* lookup state with wild-card source address */
 113                        dst = daddr;
 114                        src = (xfrm_address_t *)&in6addr_any;
 115                        break;
 116                default:
 117                        /* lookup state with wild-card addresses */
 118                        dst = (xfrm_address_t *)&in6addr_any;
 119                        src = (xfrm_address_t *)&in6addr_any;
 120                        break;
 121                }
 122
 123                x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6);
 124                if (!x)
 125                        continue;
 126
 127                spin_lock(&x->lock);
 128
 129                if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
 130                    likely(x->km.state == XFRM_STATE_VALID) &&
 131                    !xfrm_state_check_expire(x)) {
 132                        spin_unlock(&x->lock);
 133                        if (x->type->input(x, skb) > 0) {
 134                                /* found a valid state */
 135                                break;
 136                        }
 137                } else
 138                        spin_unlock(&x->lock);
 139
 140                xfrm_state_put(x);
 141                x = NULL;
 142        }
 143
 144        if (!x) {
 145                XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 146                xfrm_audit_state_notfound_simple(skb, AF_INET6);
 147                goto drop;
 148        }
 149
 150        sp->xvec[sp->len++] = x;
 151
 152        spin_lock(&x->lock);
 153
 154        x->curlft.bytes += skb->len;
 155        x->curlft.packets++;
 156
 157        spin_unlock(&x->lock);
 158
 159        return 1;
 160
 161drop:
 162        return -1;
 163}
 164EXPORT_SYMBOL(xfrm6_input_addr);
 165