netfilter: xt_connlimit: fix daddr connlimit in SNAT scenario

We use the reply tuples when limiting the connections by the destination
addresses, however, in SNAT scenario, the final reply tuples won't be
ready until SNAT is done in POSTROUING or INPUT chain, and the following
nf_conntrack_find_get() in count_tem() will get nothing, so connlimit
can't work as expected.

In this patch, the original tuples are always used, and an additional
member addr is appended to save the address in either end.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Changli Gao 2011-03-15 13:23:28 +01:00 committed by Patrick McHardy
parent f2247fbdc4
commit 8183e3a88a

View File

@ -33,8 +33,9 @@
/* we will save the tuples of all connections we care about */
struct xt_connlimit_conn {
struct list_head list;
struct nf_conntrack_tuple tuple;
struct list_head list;
struct nf_conntrack_tuple tuple;
union nf_inet_addr addr;
};
struct xt_connlimit_data {
@ -151,7 +152,7 @@ static int count_them(struct net *net,
continue;
}
if (same_source_net(addr, mask, &conn->tuple.src.u3, family))
if (same_source_net(addr, mask, &conn->addr, family))
/* same source network -> be counted! */
++matches;
nf_ct_put(found_ct);
@ -165,6 +166,7 @@ static int count_them(struct net *net,
if (conn == NULL)
return -ENOMEM;
conn->tuple = *tuple;
conn->addr = *addr;
list_add(&conn->list, hash);
++matches;
}
@ -185,15 +187,11 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
int connections;
ct = nf_ct_get(skb, &ctinfo);
if (ct != NULL) {
if (info->flags & XT_CONNLIMIT_DADDR)
tuple_ptr = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
else
tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
} else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
par->family, &tuple)) {
if (ct != NULL)
tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
par->family, &tuple))
goto hotdrop;
}
if (par->family == NFPROTO_IPV6) {
const struct ipv6hdr *iph = ipv6_hdr(skb);