diff options
| author | Patrick McHardy <kaber@trash.net> | 2006-01-06 23:05:17 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-01-07 12:57:34 -0800 |
| commit | 4e8e9de7c25315669e2d5565acc50ec379522c28 (patch) | |
| tree | 3d101041c9d28a70b8eec77af279cbfbb72b3027 /net/ipv4 | |
| parent | 3e3850e989c5d2eb1aab6f0fd9257759f0f4cbc6 (diff) | |
| download | linux-4e8e9de7c25315669e2d5565acc50ec379522c28.tar.bz2 | |
[NETFILTER]: Use conntrack information to determine if packet was NATed
Preparation for IPsec support for NAT:
Use conntrack information instead of saving the saving and comparing the
addresses to determine if a packet was NATed and needs to be rerouted to
make it easier to extend the key.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/ip_nat_standalone.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c index f04111f74e09..1bb50897a5a2 100644 --- a/net/ipv4/netfilter/ip_nat_standalone.c +++ b/net/ipv4/netfilter/ip_nat_standalone.c @@ -162,18 +162,20 @@ ip_nat_in(unsigned int hooknum, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - u_int32_t saddr, daddr; + struct ip_conntrack *ct; + enum ip_conntrack_info ctinfo; unsigned int ret; - saddr = (*pskb)->nh.iph->saddr; - daddr = (*pskb)->nh.iph->daddr; - ret = ip_nat_fn(hooknum, pskb, in, out, okfn); if (ret != NF_DROP && ret != NF_STOLEN - && ((*pskb)->nh.iph->saddr != saddr - || (*pskb)->nh.iph->daddr != daddr)) { - dst_release((*pskb)->dst); - (*pskb)->dst = NULL; + && (ct = ip_conntrack_get(*pskb, &ctinfo)) != NULL) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (ct->tuplehash[dir].tuple.src.ip != + ct->tuplehash[!dir].tuple.dst.ip) { + dst_release((*pskb)->dst); + (*pskb)->dst = NULL; + } } return ret; } @@ -200,7 +202,8 @@ ip_nat_local_fn(unsigned int hooknum, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - u_int32_t saddr, daddr; + struct ip_conntrack *ct; + enum ip_conntrack_info ctinfo; unsigned int ret; /* root is playing with raw sockets. */ @@ -208,14 +211,15 @@ ip_nat_local_fn(unsigned int hooknum, || (*pskb)->nh.iph->ihl * 4 < sizeof(struct iphdr)) return NF_ACCEPT; - saddr = (*pskb)->nh.iph->saddr; - daddr = (*pskb)->nh.iph->daddr; - ret = ip_nat_fn(hooknum, pskb, in, out, okfn); if (ret != NF_DROP && ret != NF_STOLEN - && ((*pskb)->nh.iph->saddr != saddr - || (*pskb)->nh.iph->daddr != daddr)) - return ip_route_me_harder(pskb) == 0 ? ret : NF_DROP; + && (ct = ip_conntrack_get(*pskb, &ctinfo)) != NULL) { + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + + if (ct->tuplehash[dir].tuple.dst.ip != + ct->tuplehash[!dir].tuple.src.ip) + return ip_route_me_harder(pskb) == 0 ? ret : NF_DROP; + } return ret; } |