[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>
This commit is contained in:
Pablo Neira Ayuso 2007-09-28 14:43:53 -07:00 committed by David S. Miller
parent 3583240249
commit 5faa1f4cb5
2 changed files with 41 additions and 3 deletions

View File

@ -36,6 +36,7 @@ enum ctattr_type {
CTA_USE,
CTA_ID,
CTA_NAT_DST,
CTA_TUPLE_MASTER,
__CTA_MAX
};
#define CTA_MAX (__CTA_MAX - 1)

View File

@ -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 @@ ctnetlink_change_conntrack(struct nf_conn *ct, struct nlattr *cda[])
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 @@ ctnetlink_create_conntrack(struct nlattr *cda[],
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 @@ ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
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 @@ ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
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);
}