From 9768e1ace458fa4ebf88bc3943fd8fb77113ed9c Mon Sep 17 00:00:00 2001 From: Kelvie Wong Date: Wed, 2 May 2012 14:39:24 +0000 Subject: [PATCH] netfilter: nf_ct_expect: partially implement ctnetlink_change_expect This refreshes the "timeout" attribute in existing expectations if one is given. The use case for this would be for userspace helpers to extend the lifetime of the expectation when requested, as this is not possible right now without deleting/recreating the expectation. I use this specifically for forwarding DCERPC traffic through: DCERPC has a port mapper daemon that chooses a (seemingly) random port for future traffic to go to. We expect this traffic (with a reasonable timeout), but sometimes the port mapper will tell the client to continue using the same port. This allows us to extend the expectation accordingly. Signed-off-by: Kelvie Wong Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 462ec2dbe561..6f4b00a8fc73 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -2080,7 +2080,15 @@ static int ctnetlink_change_expect(struct nf_conntrack_expect *x, const struct nlattr * const cda[]) { - return -EOPNOTSUPP; + if (cda[CTA_EXPECT_TIMEOUT]) { + if (!del_timer(&x->timeout)) + return -ETIME; + + x->timeout.expires = jiffies + + ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ; + add_timer(&x->timeout); + } + return 0; } static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = { -- 2.20.1