Merge branch 'basic-mpls-support'

Eric W. Biederman says:

====================
Basic MPLS support take 2

On top of my two pending neighbour table prep patches here is the mpls
support refactored to use them, and edited to not drop routes when
an interface goes down.  Additionally the addition of RTA_LLGATEWAY
has been replaced with the addtion of RTA_VIA.  RTA_VIA being an
attribute that includes the address family as well as the address
of the next hop.

MPLS is at it's heart simple and I have endeavoured to maintain that
simplicity in my implemenation.

This is an implementation of a RFC3032 forwarding engine, and basic MPLS
egress logic.  Which should make linux sufficient to be a mpls
forwarding node or to be a LSA (Label Switched Router) as it says in all
of the MPLS documents.  The ingress support will follow but it deserves
it's own discussion so I am pushing it separately.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 33 insertions, 0 deletions

diff --git a/include/linux/socket.h b/include/linux/socket.h
index 5c19cba34dce..fab4d0ddf4ed 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -181,6 +181,7 @@ struct ucred {
 #define AF_WANPIPE	25	/* Wanpipe API Sockets */
 #define AF_LLC		26	/* Linux LLC			*/
 #define AF_IB		27	/* Native InfiniBand address	*/
+#define AF_MPLS		28	/* MPLS */
 #define AF_CAN		29	/* Controller Area Network      */
 #define AF_TIPC		30	/* TIPC sockets			*/
 #define AF_BLUETOOTH	31	/* Bluetooth sockets 		*/
@@ -226,6 +227,7 @@ struct ucred {
 #define PF_WANPIPE	AF_WANPIPE
 #define PF_LLC		AF_LLC
 #define PF_IB		AF_IB
+#define PF_MPLS		AF_MPLS
 #define PF_CAN		AF_CAN
 #define PF_TIPC		AF_TIPC
 #define PF_BLUETOOTH	AF_BLUETOOTH
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 36faf4990c4b..2cb9acb618e9 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -26,6 +26,7 @@
 #endif
 #include <net/netns/nftables.h>
 #include <net/netns/xfrm.h>
+#include <net/netns/mpls.h>
 #include <linux/ns_common.h>
 
 struct user_namespace;
@@ -130,6 +131,9 @@ struct net {
 #if IS_ENABLED(CONFIG_IP_VS)
 	struct netns_ipvs	*ipvs;
 #endif
+#if IS_ENABLED(CONFIG_MPLS)
+	struct netns_mpls	mpls;
+#endif
 	struct sock		*diag_nlsk;
 	atomic_t		fnhe_genid;
 };
diff --git a/include/net/netns/mpls.h b/include/net/netns/mpls.h
new file mode 100644
index 000000000000..d29203651c01
--- /dev/null
+++ b/include/net/netns/mpls.h
@@ -0,0 +1,17 @@
+/*
+ * mpls in net namespaces
+ */
+
+#ifndef __NETNS_MPLS_H__
+#define __NETNS_MPLS_H__
+
+struct mpls_route;
+struct ctl_table_header;
+
+struct netns_mpls {
+	size_t platform_labels;
+	struct mpls_route __rcu * __rcu *platform_label;
+	struct ctl_table_header *ctl;
+};
+
+#endif /* __NETNS_MPLS_H__ */
diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index 5cc5d66bf519..06f75a407f74 100644
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -303,6 +303,8 @@ enum rtattr_type_t {
 	RTA_TABLE,
 	RTA_MARK,
 	RTA_MFC_STATS,
+	RTA_VIA,
+	RTA_NEWDST,
 	__RTA_MAX
 };
 
@@ -344,6 +346,12 @@ struct rtnexthop {
 #define RTNH_SPACE(len)	RTNH_ALIGN(RTNH_LENGTH(len))
 #define RTNH_DATA(rtnh)   ((struct rtattr*)(((char*)(rtnh)) + RTNH_LENGTH(0)))
 
+/* RTA_VIA */
+struct rtvia {
+	__kernel_sa_family_t	rtvia_family;
+	__u8			rtvia_addr[0];
+};
+
 /* RTM_CACHEINFO */
 
 struct rta_cacheinfo {
@@ -623,6 +631,8 @@ enum rtnetlink_groups {
 #define RTNLGRP_IPV6_NETCONF	RTNLGRP_IPV6_NETCONF
 	RTNLGRP_MDB,
 #define RTNLGRP_MDB		RTNLGRP_MDB
+	RTNLGRP_MPLS_ROUTE,
+#define RTNLGRP_MPLS_ROUTE	RTNLGRP_MPLS_ROUTE
 	__RTNLGRP_MAX
 };
 #define RTNLGRP_MAX	(__RTNLGRP_MAX - 1)