[SECMARK]: Add secmark support to conntrack

Add a secmark field to IP and NF conntracks, so that security markings
on packets can be copied to their associated connections, and also
copied back to packets as required.  This is similar to the network
mark field currently used with conntrack, although it is intended for
enforcement of security policy rather than network policy.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 20 insertions, 0 deletions

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 10eccdd4d6ea..023f81e5f96b 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -60,6 +60,18 @@ config NF_CONNTRACK_MARK
           of packets, but this mark value is kept in the conntrack session
           instead of the individual packets.
 
+config NF_CONNTRACK_SECMARK
+        bool  'Connection tracking security mark support'
+        depends on NF_CONNTRACK && NETWORK_SECMARK
+        help
+          This option enables security markings to be applied to
+          connections.  Typically they are copied to connections from
+          packets using the CONNSECMARK target and copied back from
+          connections to packets with the same target, with the packets
+          being originally labeled via SECMARK.
+
+          If unsure, say 'N'.
+
 config NF_CONNTRACK_EVENTS
         bool "Connection tracking events (EXPERIMENTAL)"
         depends on EXPERIMENTAL && NF_CONNTRACK
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index bc2bd4c3859e..cd299f4b7db1 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -990,6 +990,9 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
 #ifdef CONFIG_NF_CONNTRACK_MARK
                 conntrack->mark = exp->master->mark;
 #endif
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+                conntrack->secmark = exp->master->secmark;
+#endif
                 nf_conntrack_get(&conntrack->master->ct_general);
                 NF_CT_STAT_INC(expect_new);
         } else
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index e01d20d8e287..e34c574f0351 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -213,6 +213,11 @@ static int ct_seq_show(struct seq_file *s, void *v)
                 return -ENOSPC;
 #endif
 
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+        if (seq_printf(s, "secmark=%u ", conntrack->secmark))
+                return -ENOSPC;
+#endif
+
         if (seq_printf(s, "use=%u\n", atomic_read(&conntrack->ct_general.use)))
                 return -ENOSPC;