[SECMARK]: Add secmark support to core networking.

Add a secmark field to the skbuff structure, to allow security subsystems to
place security markings on network packets.  This is similar to the nfmark
field, except is intended for implementing security policy, rather than than
networking policy.

This patch was already acked in principle by Dave Miller.

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>

1 files changed, 22 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 23bad3bf3c9d..fe2c58e5306f 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -210,6 +210,7 @@ enum {
  *      @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
  *      @tc_index: Traffic control index
  *      @tc_verd: traffic control verdict
+ *      @secmark: security marking
  */
 
 struct sk_buff {
@@ -289,6 +290,9 @@ struct sk_buff {
 #ifdef CONFIG_NET_DMA
         dma_cookie_t            dma_cookie;
 #endif
+#ifdef CONFIG_NETWORK_SECMARK
+        __u32                   secmark;
+#endif
 
 
         /* These elements must be at the end, see alloc_skb() for details.  */
@@ -1400,5 +1404,23 @@ static inline void nf_reset(struct sk_buff *skb)
 static inline void nf_reset(struct sk_buff *skb) {}
 #endif /* CONFIG_NETFILTER */
 
+#ifdef CONFIG_NETWORK_SECMARK
+static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
+{
+        to->secmark = from->secmark;
+}
+
+static inline void skb_init_secmark(struct sk_buff *skb)
+{
+        skb->secmark = 0;
+}
+#else
+static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
+{ }
+
+static inline void skb_init_secmark(struct sk_buff *skb)
+{ }
+#endif
+
 #endif  /* __KERNEL__ */
 #endif  /* _LINUX_SKBUFF_H */