[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>

9 files changed, 74 insertions, 0 deletions

diff --git a/include/linux/netfilter_ipv4/ip_conntrack.h b/include/linux/netfilter_ipv4/ip_conntrack.h
index 17d7ef9..e0e9951 100644
--- a/include/linux/netfilter_ipv4/ip_conntrack.h
+++ b/include/linux/netfilter_ipv4/ip_conntrack.h
@@ -121,6 +121,10 @@ struct ip_conntrack
 	u_int32_t mark;
 #endif
 
+#ifdef CONFIG_IP_NF_CONNTRACK_SECMARK
+	u_int32_t secmark;
+#endif
+
 	/* Traversed often, so hopefully in different cacheline to top */
 	/* These are my tuples; original and reply */
 	struct ip_conntrack_tuple_hash tuplehash[IP_CT_DIR_MAX];
diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index dbe7a11..4111178 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -114,6 +114,10 @@ struct nf_conn
 	u_int32_t mark;
 #endif
 
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+	u_int32_t secmark;
+#endif
+
 	/* Storage reserved for other modules: */
 	union nf_conntrack_proto proto;
 
diff --git a/include/net/netfilter/nf_conntrack_compat.h b/include/net/netfilter/nf_conntrack_compat.h
index 3cac19f..f1b1482 100644
--- a/include/net/netfilter/nf_conntrack_compat.h
+++ b/include/net/netfilter/nf_conntrack_compat.h
@@ -20,6 +20,19 @@ static inline u_int32_t *nf_ct_get_mark(const struct sk_buff *skb,
 }
 #endif /* CONFIG_IP_NF_CONNTRACK_MARK */
 
+#ifdef CONFIG_IP_NF_CONNTRACK_SECMARK
+static inline u_int32_t *nf_ct_get_secmark(const struct sk_buff *skb,
+					   u_int32_t *ctinfo)
+{
+	struct ip_conntrack *ct = ip_conntrack_get(skb, ctinfo);
+
+	if (ct)
+		return &ct->secmark;
+	else
+		return NULL;
+}
+#endif /* CONFIG_IP_NF_CONNTRACK_SECMARK */
+
 #ifdef CONFIG_IP_NF_CT_ACCT
 static inline struct ip_conntrack_counter *
 nf_ct_get_counters(const struct sk_buff *skb)
@@ -70,6 +83,19 @@ static inline u_int32_t *nf_ct_get_mark(const struct sk_buff *skb,
 }
 #endif /* CONFIG_NF_CONNTRACK_MARK */
 
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+static inline u_int32_t *nf_ct_get_secmark(const struct sk_buff *skb,
+					   u_int32_t *ctinfo)
+{
+	struct nf_conn *ct = nf_ct_get(skb, ctinfo);
+
+	if (ct)
+		return &ct->secmark;
+	else
+		return NULL;
+}
+#endif /* CONFIG_NF_CONNTRACK_MARK */
+
 #ifdef CONFIG_NF_CT_ACCT
 static inline struct ip_conntrack_counter *
 nf_ct_get_counters(const struct sk_buff *skb)
diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig
index ff4b118..e1d7f5f 100644
--- a/net/ipv4/netfilter/Kconfig
+++ b/net/ipv4/netfilter/Kconfig
@@ -55,6 +55,18 @@ config IP_NF_CONNTRACK_MARK
 	  of packets, but this mark value is kept in the conntrack session
 	  instead of the individual packets.
 	
+config IP_NF_CONNTRACK_SECMARK
+	bool  'Connection tracking security mark support'
+	depends on IP_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 IP_NF_CONNTRACK_EVENTS
 	bool "Connection tracking events (EXPERIMENTAL)"
 	depends on EXPERIMENTAL && IP_NF_CONNTRACK
diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c
index 4fe9e69..7e4cf9a 100644
--- a/net/ipv4/netfilter/ip_conntrack_core.c
+++ b/net/ipv4/netfilter/ip_conntrack_core.c
@@ -724,6 +724,9 @@ init_conntrack(struct ip_conntrack_tuple *tuple,
 		/* this is ugly, but there is no other place where to put it */
 		conntrack->nat.masq_index = exp->master->nat.masq_index;
 #endif
+#ifdef CONFIG_IP_NF_CONNTRACK_SECMARK
+		conntrack->secmark = exp->master->secmark;
+#endif
 		nf_conntrack_get(&conntrack->master->ct_general);
 		CONNTRACK_STAT_INC(expect_new);
 	} else {
diff --git a/net/ipv4/netfilter/ip_conntrack_standalone.c b/net/ipv4/netfilter/ip_conntrack_standalone.c
index 6cb9b98..88445aa 100644
--- a/net/ipv4/netfilter/ip_conntrack_standalone.c
+++ b/net/ipv4/netfilter/ip_conntrack_standalone.c
@@ -189,6 +189,11 @@ static int ct_seq_show(struct seq_file *s, void *v)
 		return -ENOSPC;
 #endif
 
+#ifdef CONFIG_IP_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;
 
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 10eccdd..023f81e 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 bc2bd4c..cd299f4 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 e01d20d..e34c574 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;