netfilter: add connlabel conntrack extension
similar to connmarks, except labels are bit-based; i.e.
all labels may be attached to a flow at the same time.
Up to 128 labels are supported. Supporting more labels
is possible, but requires increasing the ct offset delta
from u8 to u16 type due to increased extension sizes.
Mapping of bit-identifier to label name is done in userspace.
The extension is enabled at run-time once "-m connlabel" netfilter
rules are added.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index e4a0c4f..85aa4b7 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -45,6 +45,7 @@
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_conntrack_timestamp.h>
#include <net/netfilter/nf_conntrack_timeout.h>
+#include <net/netfilter/nf_conntrack_labels.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_core.h>
@@ -763,6 +764,7 @@
}
EXPORT_SYMBOL_GPL(nf_conntrack_free);
+
/* Allocate a new conntrack: we return -ENOMEM if classification
failed due to stress. Otherwise it really is unclassifiable. */
static struct nf_conntrack_tuple_hash *
@@ -809,6 +811,7 @@
nf_ct_acct_ext_add(ct, GFP_ATOMIC);
nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
+ nf_ct_labels_ext_add(ct);
ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL;
nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0,
@@ -1352,6 +1355,7 @@
}
nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size);
+ nf_conntrack_labels_fini(net);
nf_conntrack_helper_fini(net);
nf_conntrack_timeout_fini(net);
nf_conntrack_ecache_fini(net);
@@ -1583,7 +1587,15 @@
ret = nf_conntrack_helper_init(net);
if (ret < 0)
goto err_helper;
+
+ ret = nf_conntrack_labels_init(net);
+ if (ret < 0)
+ goto err_labels;
+
return 0;
+
+err_labels:
+ nf_conntrack_helper_fini(net);
err_helper:
nf_conntrack_timeout_fini(net);
err_timeout: