[MLSXFRM]: Add security sid to flowi
This adds security to flow key for labeling of flows as also to allow
for making flow cache lookups based on the security label seemless.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/secid.txt b/Documentation/networking/secid.txt
new file mode 100644
index 0000000..95ea067
--- /dev/null
+++ b/Documentation/networking/secid.txt
@@ -0,0 +1,14 @@
+flowi structure:
+
+The secid member in the flow structure is used in LSMs (e.g. SELinux) to indicate
+the label of the flow. This label of the flow is currently used in selecting
+matching labeled xfrm(s).
+
+If this is an outbound flow, the label is derived from the socket, if any, or
+the incoming packet this flow is being generated as a response to (e.g. tcp
+resets, timewait ack, etc.). It is also conceivable that the label could be
+derived from other sources such as process context, device, etc., in special
+cases, as may be appropriate.
+
+If this is an inbound flow, the label is derived from the IPSec security
+associations, if any, used by the packet.
diff --git a/include/net/flow.h b/include/net/flow.h
index 04d89f7..1cee5a8 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -78,6 +78,7 @@
#define fl_icmp_type uli_u.icmpt.type
#define fl_icmp_code uli_u.icmpt.code
#define fl_ipsec_spi uli_u.spi
+ __u32 secid; /* used by xfrm; see secid.txt */
} __attribute__((__aligned__(BITS_PER_LONG/8)));
#define FLOW_DIR_IN 0