xfrm: use gre key as flow upper protocol info

The GRE Key field is intended to be used for identifying an individual
traffic flow within a tunnel. It is useful to be able to have XFRM
policy selector matches to have different policies for different
GRE tunnels.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index bcfb6b24b019..54b283229488 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -805,6 +805,9 @@ __be16 xfrm_flowi_sport(struct flowi *fl)
         case IPPROTO_MH:
                 port = htons(fl->fl_mh_type);
                 break;
+        case IPPROTO_GRE:
+                port = htonl(fl->fl_gre_key) >> 16;
+                break;
         default:
                 port = 0;       /*XXX*/
         }
@@ -826,6 +829,9 @@ __be16 xfrm_flowi_dport(struct flowi *fl)
         case IPPROTO_ICMPV6:
                 port = htons(fl->fl_icmp_code);
                 break;
+        case IPPROTO_GRE:
+                port = htonl(fl->fl_gre_key) & 0xffff;
+                break;
         default:
                 port = 0;       /*XXX*/
         }