rtnetlink: add new rtm tunnel api for tunnel id filtering

This patch adds new rtm tunnel msg and api for tunnel id
filtering in dst_metadata devices. First dst_metadata
device to use the api is vxlan driver with AF_BRIDGE
family.

This and later changes add ability in vxlan driver to do
tunnel id filtering (or vni filtering) on dst_metadata
devices. This is similar to vlan api in the vlan filtering bridge.

this patch includes selinux nlmsg_route_perms support for RTM_*TUNNEL
api from Benjamin Poirier.
Signed-off-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/if_link.h

@@ -713,7 +713,32 @@ enum ipvlan_mode {
 #define IPVLAN_F_PRIVATE	0x01
 #define IPVLAN_F_VEPA		0x02
 
+/* Tunnel RTM header */
+struct tunnel_msg {
+	__u8 family;
+	__u8 reserved1;
+	__u16 reserved2;
+	__u32 ifindex;
+};
+
 /* VXLAN section */
+enum {
+	VXLAN_VNIFILTER_ENTRY_UNSPEC,
+	VXLAN_VNIFILTER_ENTRY_START,
+	VXLAN_VNIFILTER_ENTRY_END,
+	VXLAN_VNIFILTER_ENTRY_GROUP,
+	VXLAN_VNIFILTER_ENTRY_GROUP6,
+	__VXLAN_VNIFILTER_ENTRY_MAX
+};
+#define VXLAN_VNIFILTER_ENTRY_MAX	(__VXLAN_VNIFILTER_ENTRY_MAX - 1)
+
+enum {
+	VXLAN_VNIFILTER_UNSPEC,
+	VXLAN_VNIFILTER_ENTRY,
+	__VXLAN_VNIFILTER_MAX
+};
+#define VXLAN_VNIFILTER_MAX	(__VXLAN_VNIFILTER_MAX - 1)
+
 enum {
 	IFLA_VXLAN_UNSPEC,
 	IFLA_VXLAN_ID,
@@ -745,6 +770,7 @@ enum {
 	IFLA_VXLAN_GPE,
 	IFLA_VXLAN_TTL_INHERIT,
 	IFLA_VXLAN_DF,
+	IFLA_VXLAN_VNIFILTER, /* only applicable with COLLECT_METADATA mode */
 	__IFLA_VXLAN_MAX
 };
 #define IFLA_VXLAN_MAX	(__IFLA_VXLAN_MAX - 1)

include/uapi/linux/rtnetlink.h

@@ -185,6 +185,13 @@ enum {
 	RTM_GETNEXTHOPBUCKET,
 #define RTM_GETNEXTHOPBUCKET	RTM_GETNEXTHOPBUCKET
 
+	RTM_NEWTUNNEL = 120,
+#define RTM_NEWTUNNEL	RTM_NEWTUNNEL
+	RTM_DELTUNNEL,
+#define RTM_DELTUNNEL	RTM_DELTUNNEL
+	RTM_GETTUNNEL,
+#define RTM_GETTUNNEL	RTM_GETTUNNEL
+
 	__RTM_MAX,
 #define RTM_MAX		(((__RTM_MAX + 3) & ~3) - 1)
 };
@@ -756,6 +763,8 @@ enum rtnetlink_groups {
 #define RTNLGRP_BRVLAN		RTNLGRP_BRVLAN
 	RTNLGRP_MCTP_IFADDR,
 #define RTNLGRP_MCTP_IFADDR	RTNLGRP_MCTP_IFADDR
+	RTNLGRP_TUNNEL,
+#define RTNLGRP_TUNNEL		RTNLGRP_TUNNEL
 	__RTNLGRP_MAX
 };
 #define RTNLGRP_MAX	(__RTNLGRP_MAX - 1)

security/selinux/nlmsgtab.c

@@ -91,6 +91,9 @@ static const struct nlmsg_perm nlmsg_route_perms[] =
 	{ RTM_NEWNEXTHOPBUCKET,	NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 	{ RTM_DELNEXTHOPBUCKET,	NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
 	{ RTM_GETNEXTHOPBUCKET,	NETLINK_ROUTE_SOCKET__NLMSG_READ  },
+	{ RTM_NEWTUNNEL,	NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
+	{ RTM_DELTUNNEL,	NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
+	{ RTM_GETTUNNEL,	NETLINK_ROUTE_SOCKET__NLMSG_READ  },
 };
 
 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =
@@ -176,7 +179,7 @@ int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
 		 * structures at the top of this file with the new mappings
 		 * before updating the BUILD_BUG_ON() macro!
 		 */
-		BUILD_BUG_ON(RTM_MAX != (RTM_NEWNEXTHOPBUCKET + 3));
+		BUILD_BUG_ON(RTM_MAX != (RTM_NEWTUNNEL + 3));
 		err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
 				 sizeof(nlmsg_route_perms));
 		break;