netfilter: xt_connbytes: Force CT accounting to be enabled

Check at rule install time that CT accounting is enabled. Force it
to be enabled if not while also emitting a warning since this is not
the default state.

This is in preparation for deprecating CONFIG_NF_CT_ACCT upon which
CONFIG_NETFILTER_XT_MATCH_CONNBYTES depended being set.

Added 2 CT accounting support functions:

nf_ct_acct_enabled() - Get CT accounting state.
nf_ct_set_acct() - Enable/disable CT accountuing.

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/net/netfilter/nf_conntrack_acct.h b/include/net/netfilter/nf_conntrack_acct.h
index 03e218f0be43..4e9c63a20db2 100644
--- a/include/net/netfilter/nf_conntrack_acct.h
+++ b/include/net/netfilter/nf_conntrack_acct.h
@@ -45,6 +45,18 @@ struct nf_conn_counter *nf_ct_acct_ext_add(struct nf_conn *ct, gfp_t gfp)
 extern unsigned int
 seq_print_acct(struct seq_file *s, const struct nf_conn *ct, int dir);
 
+/* Check if connection tracking accounting is enabled */
+static inline bool nf_ct_acct_enabled(struct net *net)
+{
+        return net->ct.sysctl_acct != 0;
+}
+
+/* Enable/disable connection tracking accounting */
+static inline void nf_ct_set_acct(struct net *net, bool enable)
+{
+        net->ct.sysctl_acct = enable;
+}
+
 extern int nf_conntrack_acct_init(struct net *net);
 extern void nf_conntrack_acct_fini(struct net *net);