summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorStefan Berger <stefanb@linux.vnet.ibm.com>2011-02-11 18:00:07 +0100
committerPatrick McHardy <kaber@trash.net>2011-02-11 18:00:07 +0100
commit44bd4de9c2270b22c3c898310102bc6be9ed2978 (patch)
treeb14ddafd121b1c1a29580c0278e9cf14667aa96a /net
parentc16e19c11730199c1df686b160c9c972ad28baf8 (diff)
netfilter: xt_connlimit: connlimit-above early loop termination
The patch below introduces an early termination of the loop that is counting matches. It terminates once the counter has exceeded the threshold provided by the user. There's no point in continuing the loop afterwards and looking at other entries. It plays together with the following code further below: return (connections > info->limit) ^ info->inverse; where connections is the result of the counted connection, which in turn is the matches variable in the loop. So once -> matches = info->limit + 1 alias -> matches > info->limit alias -> matches > threshold we can terminate the loop. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Patrick McHardy <kaber@trash.net>
Diffstat (limited to 'net')
-rw-r--r--net/netfilter/xt_connlimit.c13
1 files changed, 10 insertions, 3 deletions
diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c
index e029c4807404..82ce7c5fbbc2 100644
--- a/net/netfilter/xt_connlimit.c
+++ b/net/netfilter/xt_connlimit.c
@@ -97,7 +97,8 @@ static int count_them(struct net *net,
const struct nf_conntrack_tuple *tuple,
const union nf_inet_addr *addr,
const union nf_inet_addr *mask,
- u_int8_t family)
+ u_int8_t family,
+ unsigned int threshold)
{
const struct nf_conntrack_tuple_hash *found;
struct xt_connlimit_conn *conn;
@@ -151,9 +152,14 @@ 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->tuple.src.u3, family)) {
/* same source network -> be counted! */
++matches;
+ if (matches > threshold) {
+ nf_ct_put(found_ct);
+ break;
+ }
+ }
nf_ct_put(found_ct);
}
@@ -207,7 +213,8 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
spin_lock_bh(&info->data->lock);
connections = count_them(net, info->data, tuple_ptr, &addr,
- &info->mask, par->family);
+ &info->mask, par->family,
+ info->limit);
spin_unlock_bh(&info->data->lock);
if (connections < 0)