[PATCH nf-next] netfilter: nft_ct: make byte/packet expr more friendly

[PATCH nf-next] netfilter: nft_ct: make byte/packet expr more friendly

[Liping Zhang]

From: Liping Zhang <liping.zhang@spreadtrum.com>

If we want to use ct packets expr, and add a rule like follows:
  # nft add rule filter input ct packets gt 1 counter

We will find that no packets will hit it, because
nf_conntrack_acct is disabled by default. So It will
not work until we enable it manually via
"echo 1 > /proc/sys/net/netfilter/nf_conntrack_acct".

This is not friendly, so like xt_connbytes do, if the user
want to use ct byte/packet expr, enable nf_conntrack_acct
automatically.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
---
 net/netfilter/nft_ct.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index 137e308..7ce8fd7 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -355,6 +355,9 @@ static int nft_ct_get_init(const struct nft_ctx *ctx,
 	if (err < 0)
 		return err;
 
+	if (priv->key == NFT_CT_BYTES || priv->key == NFT_CT_PKTS)
+		nf_ct_set_acct(ctx->net, true);
+
 	return 0;
 }
 
-- 
2.5.5

Re: [PATCH nf-next] netfilter: nft_ct: make byte/packet expr more friendly

[Florian Westphal]

Liping Zhang <zlpnobody@163.com> wrote:
> From: Liping Zhang <liping.zhang@spreadtrum.com>
> 
> If we want to use ct packets expr, and add a rule like follows:
>   # nft add rule filter input ct packets gt 1 counter
> 
> We will find that no packets will hit it, because
> nf_conntrack_acct is disabled by default. So It will
> not work until we enable it manually via
> "echo 1 > /proc/sys/net/netfilter/nf_conntrack_acct".
> 
> This is not friendly, so like xt_connbytes do, if the user
> want to use ct byte/packet expr, enable nf_conntrack_acct
> automatically.

Good idea, thanks!

Re: [PATCH nf-next] netfilter: nft_ct: make byte/packet expr more friendly

[Pablo Neira Ayuso]

On Tue, Jul 05, 2016 at 11:23:00PM +0800, Liping Zhang wrote:
> From: Liping Zhang <liping.zhang@spreadtrum.com>
> 
> If we want to use ct packets expr, and add a rule like follows:
>   # nft add rule filter input ct packets gt 1 counter
> 
> We will find that no packets will hit it, because
> nf_conntrack_acct is disabled by default. So It will
> not work until we enable it manually via
> "echo 1 > /proc/sys/net/netfilter/nf_conntrack_acct".
> 
> This is not friendly, so like xt_connbytes do, if the user
> want to use ct byte/packet expr, enable nf_conntrack_acct
> automatically.

Applied, thanks.