netfilter: nf_conntrack: push zone object into functions

This patch replaces the zone id which is pushed down into functions
with the actual zone object. It's a bigger one-time change, but
needed for later on extending zones with a direction parameter, and
thus decoupling this additional information from all call-sites.

No functional changes in this patch.

The default zone becomes a global const object, namely nf_ct_zone_dflt
and will be returned directly in various cases, one being, when there's
f.e. no zoning support.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 23 insertions, 10 deletions

diff --git a/include/net/netfilter/nf_conntrack_zones.h b/include/net/netfilter/nf_conntrack_zones.h
index 034efe8d45a5..0788bb0f267d 100644
--- a/include/net/netfilter/nf_conntrack_zones.h
+++ b/include/net/netfilter/nf_conntrack_zones.h
@@ -1,25 +1,38 @@
 #ifndef _NF_CONNTRACK_ZONES_H
 #define _NF_CONNTRACK_ZONES_H
 
-#define NF_CT_DEFAULT_ZONE	0
-
-#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
-#include <net/netfilter/nf_conntrack_extend.h>
+#define NF_CT_DEFAULT_ZONE_ID	0
 
 struct nf_conntrack_zone {
 	u16	id;
 };
 
-static inline u16 nf_ct_zone(const struct nf_conn *ct)
+extern const struct nf_conntrack_zone nf_ct_zone_dflt;
+
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
+#include <net/netfilter/nf_conntrack_extend.h>
+
+static inline const struct nf_conntrack_zone *
+nf_ct_zone(const struct nf_conn *ct)
 {
+	const struct nf_conntrack_zone *nf_ct_zone = NULL;
+
 #ifdef CONFIG_NF_CONNTRACK_ZONES
-	struct nf_conntrack_zone *nf_ct_zone;
 	nf_ct_zone = nf_ct_ext_find(ct, NF_CT_EXT_ZONE);
-	if (nf_ct_zone)
-		return nf_ct_zone->id;
 #endif
-	return NF_CT_DEFAULT_ZONE;
+	return nf_ct_zone ? nf_ct_zone : &nf_ct_zone_dflt;
 }
 
-#endif /* CONFIG_NF_CONNTRACK || CONFIG_NF_CONNTRACK_MODULE */
+static inline const struct nf_conntrack_zone *
+nf_ct_zone_tmpl(const struct nf_conn *tmpl)
+{
+	return tmpl ? nf_ct_zone(tmpl) : &nf_ct_zone_dflt;
+}
+
+static inline bool nf_ct_zone_equal(const struct nf_conn *a,
+				    const struct nf_conntrack_zone *b)
+{
+	return nf_ct_zone(a)->id == b->id;
+}
+#endif /* IS_ENABLED(CONFIG_NF_CONNTRACK) */
 #endif /* _NF_CONNTRACK_ZONES_H */