SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/ipv6/xfrm6_input.c

   1 /*
   2  * xfrm6_input.c: based on net/ipv4/xfrm4_input.c
   3  *
   4  * Authors:
   5  *      Mitsuru KANDA @USAGI
   6  *      Kazunori MIYAZAWA @USAGI
   7  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   8  *      YOSHIFUJI Hideaki @USAGI
   9  *              IPv6 support
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/string.h>
  14 #include <linux/netfilter.h>
  15 #include <linux/netfilter_ipv6.h>
  16 #include <net/ipv6.h>
  17 #include <net/xfrm.h>
  18
  19 int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb)
  20 {
  21         return xfrm6_extract_header(skb);
  22 }
  23
  24 int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
  25 {
  26         XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
  27         XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
  28         return xfrm_input(skb, nexthdr, spi, 0);
  29 }
  30 EXPORT_SYMBOL(xfrm6_rcv_spi);
  31
  32 int xfrm6_transport_finish(struct sk_buff *skb, int async)
  33 {
  34         skb_network_header(skb)[IP6CB(skb)->nhoff] =
  35                 XFRM_MODE_SKB_CB(skb)->protocol;
  36
  37 #ifdef CONFIG_NETFILTER
  38         ipv6_hdr(skb)->payload_len = htons(skb->len);
  39         __skb_push(skb, skb->data - skb_network_header(skb));
  40
  41         NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, skb->dev, NULL,
  42                 ip6_rcv_finish);
  43         return -1;
  44 #else
  45         if (async)
  46                 return ip6_rcv_finish(skb);
  47
  48         return 1;
  49 #endif
  50 }
  51
  52 int xfrm6_rcv(struct sk_buff *skb)
  53 {
  54         return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
  55                              0);
  56 }
  57
  58 EXPORT_SYMBOL(xfrm6_rcv);
  59
  60 int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
  61                      xfrm_address_t *saddr, u8 proto)
  62 {
  63         struct xfrm_state *x = NULL;
  64         int wildcard = 0;
  65         xfrm_address_t *xany;
  66         int nh = 0;
  67         int i = 0;
  68
  69         /* Allocate new secpath or COW existing one. */
  70         if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
  71                 struct sec_path *sp;
  72
  73                 sp = secpath_dup(skb->sp);
  74                 if (!sp) {
  75                         XFRM_INC_STATS(LINUX_MIB_XFRMINERROR);
  76                         goto drop;
  77                 }
  78                 if (skb->sp)
  79                         secpath_put(skb->sp);
  80                 skb->sp = sp;
  81         }
  82
  83         if (1 + skb->sp->len == XFRM_MAX_DEPTH) {
  84                 XFRM_INC_STATS(LINUX_MIB_XFRMINBUFFERERROR);
  85                 goto drop;
  86         }
  87
  88         xany = (xfrm_address_t *)&in6addr_any;
  89
  90         for (i = 0; i < 3; i++) {
  91                 xfrm_address_t *dst, *src;
  92                 switch (i) {
  93                 case 0:
  94                         dst = daddr;
  95                         src = saddr;
  96                         break;
  97                 case 1:
  98                         /* lookup state with wild-card source address */
  99                         wildcard = 1;
 100                         dst = daddr;
 101                         src = xany;
 102                         break;
 103                 case 2:
 104                 default:
 105                         /* lookup state with wild-card addresses */
 106                         wildcard = 1; /* XXX */
 107                         dst = xany;
 108                         src = xany;
 109                         break;
 110                 }
 111
 112                 x = xfrm_state_lookup_byaddr(dst, src, proto, AF_INET6);
 113                 if (!x)
 114                         continue;
 115
 116                 spin_lock(&x->lock);
 117
 118                 if (wildcard) {
 119                         if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
 120                                 spin_unlock(&x->lock);
 121                                 xfrm_state_put(x);
 122                                 x = NULL;
 123                                 continue;
 124                         }
 125                 }
 126
 127                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 128                         spin_unlock(&x->lock);
 129                         xfrm_state_put(x);
 130                         x = NULL;
 131                         continue;
 132                 }
 133                 if (xfrm_state_check_expire(x)) {
 134                         spin_unlock(&x->lock);
 135                         xfrm_state_put(x);
 136                         x = NULL;
 137                         continue;
 138                 }
 139
 140                 spin_unlock(&x->lock);
 141
 142                 nh = x->type->input(x, skb);
 143                 if (nh <= 0) {
 144                         xfrm_state_put(x);
 145                         x = NULL;
 146                         continue;
 147                 }
 148
 149                 /* Found a state */
 150                 break;
 151         }
 152
 153         if (!x) {
 154                 XFRM_INC_STATS(LINUX_MIB_XFRMINNOSTATES);
 155                 goto drop;
 156         }
 157
 158         skb->sp->xvec[skb->sp->len++] = x;
 159
 160         spin_lock(&x->lock);
 161
 162         x->curlft.bytes += skb->len;
 163         x->curlft.packets++;
 164
 165         spin_unlock(&x->lock);
 166
 167         return 1;
 168
 169 drop:
 170         return -1;
 171 }
 172
 173 EXPORT_SYMBOL(xfrm6_input_addr);