kernel-ark/net/ipv6/xfrm6_input.c
Herbert Xu 13996378e6 [IPSEC]: Rename mode to outer_mode and add inner_mode
This patch adds a new field to xfrm states called inner_mode.  The existing
mode object is renamed to outer_mode.

This is the first part of an attempt to fix inter-family transforms.  As it
is we always use the outer family when determining which mode to use.  As a
result we may end up shoving IPv4 packets into netfilter6 and vice versa.

What we really want is to use the inner family for the first part of outbound
processing and the outer family for the second part.  For inbound processing
we'd use the opposite pairing.

I've also added a check to prevent silly combinations such as transport mode
with inter-family transforms.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-17 21:35:51 -07:00

248 lines
4.6 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, int nexthdr, __be32 spi)
{
int err;
__be32 seq;
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
unsigned int nhoff;
nhoff = IP6CB(skb)->nhoff;
seq = 0;
if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
goto drop;
do {
struct ipv6hdr *iph = ipv6_hdr(skb);
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_network_header(skb)[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->outer_mode->input(x, skb))
goto drop;
if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
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;
nf_reset(skb);
if (decaps) {
dst_release(skb->dst);
skb->dst = NULL;
netif_rx(skb);
return -1;
} else {
#ifdef CONFIG_NETFILTER
ipv6_hdr(skb)->payload_len = htons(skb->len);
__skb_push(skb, skb->data - skb_network_header(skb));
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 *skb)
{
return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
0);
}
EXPORT_SYMBOL(xfrm6_rcv);
int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
xfrm_address_t *saddr, u8 proto)
{
struct xfrm_state *x = NULL;
int wildcard = 0;
xfrm_address_t *xany;
struct xfrm_state *xfrm_vec_one = NULL;
int nh = 0;
int i = 0;
xany = (xfrm_address_t *)&in6addr_any;
for (i = 0; i < 3; i++) {
xfrm_address_t *dst, *src;
switch (i) {
case 0:
dst = daddr;
src = saddr;
break;
case 1:
/* lookup state with wild-card source address */
wildcard = 1;
dst = daddr;
src = xany;
break;
case 2:
default:
/* lookup state with wild-card addresses */
wildcard = 1; /* XXX */
dst = xany;
src = xany;
break;
}
x = xfrm_state_lookup_byaddr(dst, src, proto, AF_INET6);
if (!x)
continue;
spin_lock(&x->lock);
if (wildcard) {
if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
spin_unlock(&x->lock);
xfrm_state_put(x);
x = NULL;
continue;
}
}
if (unlikely(x->km.state != XFRM_STATE_VALID)) {
spin_unlock(&x->lock);
xfrm_state_put(x);
x = NULL;
continue;
}
if (xfrm_state_check_expire(x)) {
spin_unlock(&x->lock);
xfrm_state_put(x);
x = NULL;
continue;
}
nh = x->type->input(x, skb);
if (nh <= 0) {
spin_unlock(&x->lock);
xfrm_state_put(x);
x = NULL;
continue;
}
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec_one = x;
break;
}
if (!xfrm_vec_one)
goto drop;
/* 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 (1 + skb->sp->len > XFRM_MAX_DEPTH)
goto drop;
skb->sp->xvec[skb->sp->len] = xfrm_vec_one;
skb->sp->len ++;
return 1;
drop:
if (xfrm_vec_one)
xfrm_state_put(xfrm_vec_one);
return -1;
}
EXPORT_SYMBOL(xfrm6_input_addr);