netfilter: nf_tables: add SECMARK support

Add the ability to set the security context of packets within the nf_tables framework.
Add a nft_object for holding security contexts in the kernel and manipulating packets on the wire.

Convert the security context strings at rule addition time to security identifiers.
This is the same behavior like in xt_SECMARK and offers better performance than computing it per packet.

Set the maximum security context length to 256.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 24 insertions, 4 deletions

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index ffd5c0f9412b..3fbce3b9c5ec 100644
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -249,12 +249,24 @@ static struct nft_expr_type *nft_basic_types[] = {
 	&nft_exthdr_type,
 };
 
+static struct nft_object_type *nft_basic_objects[] = {
+#ifdef CONFIG_NETWORK_SECMARK
+	&nft_secmark_obj_type,
+#endif
+};
+
 int __init nf_tables_core_module_init(void)
 {
-	int err, i;
+	int err, i, j = 0;
+
+	for (i = 0; i < ARRAY_SIZE(nft_basic_objects); i++) {
+		err = nft_register_obj(nft_basic_objects[i]);
+		if (err)
+			goto err;
+	}
 
-	for (i = 0; i < ARRAY_SIZE(nft_basic_types); i++) {
-		err = nft_register_expr(nft_basic_types[i]);
+	for (j = 0; j < ARRAY_SIZE(nft_basic_types); j++) {
+		err = nft_register_expr(nft_basic_types[j]);
 		if (err)
 			goto err;
 	}
@@ -262,8 +274,12 @@ int __init nf_tables_core_module_init(void)
 	return 0;
 
 err:
+	while (j-- > 0)
+		nft_unregister_expr(nft_basic_types[j]);
+
 	while (i-- > 0)
-		nft_unregister_expr(nft_basic_types[i]);
+		nft_unregister_obj(nft_basic_objects[i]);
+
 	return err;
 }
 
@@ -274,4 +290,8 @@ void nf_tables_core_module_exit(void)
 	i = ARRAY_SIZE(nft_basic_types);
 	while (i-- > 0)
 		nft_unregister_expr(nft_basic_types[i]);
+
+	i = ARRAY_SIZE(nft_basic_objects);
+	while (i-- > 0)
+		nft_unregister_obj(nft_basic_objects[i]);
 }