linux/net/ipv6/xfrm6_input.c
Herbert Xu b59f45d0b2 [IPSEC] xfrm: Abstract out encapsulation modes
This patch adds the structure xfrm_mode.  It is meant to represent
the operations carried out by transport/tunnel modes.

By doing this we allow additional encapsulation modes to be added
without clogging up the xfrm_input/xfrm_output paths.

Candidate modes include 4-to-6 tunnel mode, 6-to-4 tunnel mode, and
BEET modes.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:28:39 -07:00

140 lines
2.7 KiB
C

/*
* xfrm6_input.c: based on net/ipv4/xfrm4_input.c
*
* Authors:
* Mitsuru KANDA @USAGI
* Kazunori MIYAZAWA @USAGI
* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
* YOSHIFUJI Hideaki @USAGI
* IPv6 support
*/
#include <linux/module.h>
#include <linux/string.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
int xfrm6_rcv_spi(struct sk_buff *skb, u32 spi)
{
int err;
u32 seq;
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
int nexthdr;
unsigned int nhoff;
nhoff = IP6CB(skb)->nhoff;
nexthdr = skb->nh.raw[nhoff];
seq = 0;
if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
goto drop;
do {
struct ipv6hdr *iph = skb->nh.ipv6h;
if (xfrm_nr == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, nexthdr, AF_INET6);
if (x == NULL)
goto drop;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
nexthdr = x->type->input(x, skb);
if (nexthdr <= 0)
goto drop_unlock;
skb->nh.raw[nhoff] = nexthdr;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++] = x;
if (x->mode->input(x, skb))
goto drop;
if (x->props.mode) { /* XXX */
decaps = 1;
break;
}
if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
goto drop;
} while (!err);
/* Allocate new secpath or COW existing one. */
if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
struct sec_path *sp;
sp = secpath_dup(skb->sp);
if (!sp)
goto drop;
if (skb->sp)
secpath_put(skb->sp);
skb->sp = sp;
}
if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
goto drop;
memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
xfrm_nr * sizeof(xfrm_vec[0]));
skb->sp->len += xfrm_nr;
skb->ip_summed = CHECKSUM_NONE;
nf_reset(skb);
if (decaps) {
if (!(skb->dev->flags&IFF_LOOPBACK)) {
dst_release(skb->dst);
skb->dst = NULL;
}
netif_rx(skb);
return -1;
} else {
#ifdef CONFIG_NETFILTER
skb->nh.ipv6h->payload_len = htons(skb->len);
__skb_push(skb, skb->data - skb->nh.raw);
NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
ip6_rcv_finish);
return -1;
#else
return 1;
#endif
}
drop_unlock:
spin_unlock(&x->lock);
xfrm_state_put(x);
drop:
while (--xfrm_nr >= 0)
xfrm_state_put(xfrm_vec[xfrm_nr]);
kfree_skb(skb);
return -1;
}
EXPORT_SYMBOL(xfrm6_rcv_spi);
int xfrm6_rcv(struct sk_buff **pskb)
{
return xfrm6_rcv_spi(*pskb, 0);
}