From 5faa1f4cb5a1f124f76172d775467f4a9db5b452 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 28 Sep 2007 14:43:53 -0700 Subject: [PATCH] [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 Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/linux/netfilter/nfnetlink_conntrack.h | 1 + net/netfilter/nf_conntrack_netlink.c | 43 +++++++++++++++++-- 2 files changed, 41 insertions(+), 3 deletions(-) diff --git a/include/linux/netfilter/nfnetlink_conntrack.h b/include/linux/netfilter/nfnetlink_conntrack.h index d7c3503972..4affa3fe78 100644 --- a/include/linux/netfilter/nfnetlink_conntrack.h +++ b/include/linux/netfilter/nfnetlink_conntrack.h @@ -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) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 2abd648f7d..9be1826e6c 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -4,7 +4,7 @@ * (C) 2001 by Jay Schulist * (C) 2002-2006 by Harald Welte * (C) 2003 by Patrick Mchardy - * (C) 2005-2006 by Pablo Neira Ayuso + * (C) 2005-2007 by Pablo Neira Ayuso * * 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); } -- 2.39.5