netfilter: connlabels: Export setting connlabel length
Add functions to change connlabel length into nf_conntrack_labels.c so
they may be reused by other modules like OVS and nftables without
needing to jump through xt_match_check() hoops.
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nf_conntrack_labels.c b/net/netfilter/nf_conntrack_labels.c
index daa7c13..3ce5c31 100644
--- a/net/netfilter/nf_conntrack_labels.c
+++ b/net/netfilter/nf_conntrack_labels.c
@@ -14,6 +14,8 @@
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_labels.h>
+static spinlock_t nf_connlabels_lock;
+
static unsigned int label_bits(const struct nf_conn_labels *l)
{
unsigned int longs = l->words;
@@ -89,6 +91,35 @@
}
EXPORT_SYMBOL_GPL(nf_connlabels_replace);
+int nf_connlabels_get(struct net *net, unsigned int n_bits)
+{
+ size_t words;
+
+ if (n_bits > (NF_CT_LABELS_MAX_SIZE * BITS_PER_BYTE))
+ return -ERANGE;
+
+ words = BITS_TO_LONGS(n_bits);
+
+ spin_lock(&nf_connlabels_lock);
+ net->ct.labels_used++;
+ if (words > net->ct.label_words)
+ net->ct.label_words = words;
+ spin_unlock(&nf_connlabels_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nf_connlabels_get);
+
+void nf_connlabels_put(struct net *net)
+{
+ spin_lock(&nf_connlabels_lock);
+ net->ct.labels_used--;
+ if (net->ct.labels_used == 0)
+ net->ct.label_words = 0;
+ spin_unlock(&nf_connlabels_lock);
+}
+EXPORT_SYMBOL_GPL(nf_connlabels_put);
+
static struct nf_ct_ext_type labels_extend __read_mostly = {
.len = sizeof(struct nf_conn_labels),
.align = __alignof__(struct nf_conn_labels),
@@ -97,6 +128,7 @@
int nf_conntrack_labels_init(void)
{
+ spin_lock_init(&nf_connlabels_lock);
return nf_ct_extend_register(&labels_extend);
}