netfilter: ctnetlink: deliver labels to userspace
Introduce CTA_LABELS attribute to send a bit-vector of currently active labels
to userspace.
Future patch will permit userspace to also set/delete active labels.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index e0b10ee..5f53863 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -324,6 +324,40 @@
#define ctnetlink_dump_secctx(a, b) (0)
#endif
+#ifdef CONFIG_NF_CONNTRACK_LABELS
+static int ctnetlink_label_size(const struct nf_conn *ct)
+{
+ struct nf_conn_labels *labels = nf_ct_labels_find(ct);
+
+ if (!labels)
+ return 0;
+ return nla_total_size(labels->words * sizeof(long));
+}
+
+static int
+ctnetlink_dump_labels(struct sk_buff *skb, const struct nf_conn *ct)
+{
+ struct nf_conn_labels *labels = nf_ct_labels_find(ct);
+ unsigned int len, i;
+
+ if (!labels)
+ return 0;
+
+ len = labels->words * sizeof(long);
+ i = 0;
+ do {
+ if (labels->bits[i] != 0)
+ return nla_put(skb, CTA_LABELS, len, labels->bits);
+ i++;
+ } while (i < labels->words);
+
+ return 0;
+}
+#else
+#define ctnetlink_dump_labels(a, b) (0)
+#define ctnetlink_label_size(a) (0)
+#endif
+
#define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
static inline int
@@ -464,6 +498,7 @@
ctnetlink_dump_helpinfo(skb, ct) < 0 ||
ctnetlink_dump_mark(skb, ct) < 0 ||
ctnetlink_dump_secctx(skb, ct) < 0 ||
+ ctnetlink_dump_labels(skb, ct) < 0 ||
ctnetlink_dump_id(skb, ct) < 0 ||
ctnetlink_dump_use(skb, ct) < 0 ||
ctnetlink_dump_master(skb, ct) < 0 ||
@@ -562,6 +597,7 @@
+ nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
#endif
+ ctnetlink_proto_size(ct)
+ + ctnetlink_label_size(ct)
;
}
@@ -663,6 +699,9 @@
&& ctnetlink_dump_secctx(skb, ct) < 0)
goto nla_put_failure;
#endif
+ if (events & (1 << IPCT_LABEL) &&
+ ctnetlink_dump_labels(skb, ct) < 0)
+ goto nla_put_failure;
if (events & (1 << IPCT_RELATED) &&
ctnetlink_dump_master(skb, ct) < 0)
@@ -1986,6 +2025,8 @@
if (ct->mark && ctnetlink_dump_mark(skb, ct) < 0)
goto nla_put_failure;
#endif
+ if (ctnetlink_dump_labels(skb, ct) < 0)
+ goto nla_put_failure;
rcu_read_unlock();
return 0;