[IPSEC]: Added xfrm_decode_session_reverse and xfrmX_policy_check_reverse

RFC 4301 requires us to relookup ICMP traffic that does not match any
policies using the reverse of its payload.  This patch adds the functions
xfrm_decode_session_reverse and xfrmX_policy_check_reverse so we can get
the reverse flow to perform such a lookup.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu
2007-12-12 10:44:16 -08:00
committed by David S. Miller
parent 815f4e57e9
commit d5422efe68
5 changed files with 80 additions and 21 deletions

View File

@@ -123,7 +123,7 @@ static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
}
static inline void
_decode_session6(struct sk_buff *skb, struct flowi *fl)
_decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
{
u16 offset = skb_network_header_len(skb);
struct ipv6hdr *hdr = ipv6_hdr(skb);
@@ -132,8 +132,8 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl)
u8 nexthdr = nh[IP6CB(skb)->nhoff];
memset(fl, 0, sizeof(struct flowi));
ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
ipv6_addr_copy(&fl->fl6_dst, reverse ? &hdr->saddr : &hdr->daddr);
ipv6_addr_copy(&fl->fl6_src, reverse ? &hdr->daddr : &hdr->saddr);
while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
nh = skb_network_header(skb);
@@ -156,8 +156,8 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl)
if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
__be16 *ports = (__be16 *)exthdr;
fl->fl_ip_sport = ports[0];
fl->fl_ip_dport = ports[1];
fl->fl_ip_sport = ports[!!reverse];
fl->fl_ip_dport = ports[!reverse];
}
fl->proto = nexthdr;
return;