[NETFILTER]: nf_conntrack_netlink: add support to related connections
This patch adds support to relate a connection to an existing master
connection. This patch is used by conntrackd to correctly replicate
related connections.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 2abd648..9be1826 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -4,7 +4,7 @@
* (C) 2001 by Jay Schulist <jschlst@samba.org>
* (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
* (C) 2003 by Patrick Mchardy <kaber@trash.net>
- * (C) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
+ * (C) 2005-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* Initial connection tracking via netlink development funded and
* generally made possible by Network Robots, Inc. (www.networkrobots.com)
@@ -975,7 +975,8 @@
static int
ctnetlink_create_conntrack(struct nlattr *cda[],
struct nf_conntrack_tuple *otuple,
- struct nf_conntrack_tuple *rtuple)
+ struct nf_conntrack_tuple *rtuple,
+ struct nf_conn *master_ct)
{
struct nf_conn *ct;
int err = -EINVAL;
@@ -1022,6 +1023,10 @@
rcu_assign_pointer(help->helper, helper);
}
+ /* setup master conntrack: this is a confirmed expectation */
+ if (master_ct)
+ ct->master = master_ct;
+
add_timer(&ct->timeout);
nf_conntrack_hash_insert(ct);
@@ -1064,10 +1069,37 @@
h = __nf_conntrack_find(&rtuple, NULL);
if (h == NULL) {
+ struct nf_conntrack_tuple master;
+ struct nf_conntrack_tuple_hash *master_h = NULL;
+ struct nf_conn *master_ct = NULL;
+
+ if (cda[CTA_TUPLE_MASTER]) {
+ err = ctnetlink_parse_tuple(cda,
+ &master,
+ CTA_TUPLE_MASTER,
+ u3);
+ if (err < 0)
+ return err;
+
+ master_h = __nf_conntrack_find(&master, NULL);
+ if (master_h == NULL) {
+ err = -ENOENT;
+ goto out_unlock;
+ }
+ master_ct = nf_ct_tuplehash_to_ctrack(master_h);
+ atomic_inc(&master_ct->ct_general.use);
+ }
+
write_unlock_bh(&nf_conntrack_lock);
err = -ENOENT;
if (nlh->nlmsg_flags & NLM_F_CREATE)
- err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
+ err = ctnetlink_create_conntrack(cda,
+ &otuple,
+ &rtuple,
+ master_ct);
+ if (err < 0 && master_ct)
+ nf_ct_put(master_ct);
+
return err;
}
/* implicit 'else' */
@@ -1081,6 +1113,11 @@
err = -EINVAL;
goto out_unlock;
}
+ /* can't link an existing conntrack to a master */
+ if (cda[CTA_TUPLE_MASTER]) {
+ err = -EINVAL;
+ goto out_unlock;
+ }
err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h),
cda);
}