ip_tunnel: add mpls over gre support
This commit introduces the MPLSoGRE support (RFC 4023), using ip tunnel
API by simply adding ipgre_tunnel_encap_(add|del)_mpls_ops() and the new
tunnel type TUNNEL_ENCAP_MPLS.
Signed-off-by: Amine Kherbouche <amine.kherbouche@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index c5b9ce4..9745e8f 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -16,6 +16,7 @@
#include <net/arp.h>
#include <net/ip_fib.h>
#include <net/netevent.h>
+#include <net/ip_tunnels.h>
#include <net/netns/generic.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
@@ -39,6 +40,36 @@ static int one = 1;
static int label_limit = (1 << 20) - 1;
static int ttl_max = 255;
+#if IS_ENABLED(CONFIG_NET_IP_TUNNEL)
+size_t ipgre_mpls_encap_hlen(struct ip_tunnel_encap *e)
+{
+ return sizeof(struct mpls_shim_hdr);
+}
+
+static const struct ip_tunnel_encap_ops mpls_iptun_ops = {
+ .encap_hlen = ipgre_mpls_encap_hlen,
+};
+
+static int ipgre_tunnel_encap_add_mpls_ops(void)
+{
+ return ip_tunnel_encap_add_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
+}
+
+static void ipgre_tunnel_encap_del_mpls_ops(void)
+{
+ ip_tunnel_encap_del_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
+}
+#else
+static int ipgre_tunnel_encap_add_mpls_ops(void)
+{
+ return 0;
+}
+
+static void ipgre_tunnel_encap_del_mpls_ops(void)
+{
+}
+#endif
+
static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
struct nlmsghdr *nlh, struct net *net, u32 portid,
unsigned int nlm_flags);
@@ -2485,6 +2516,10 @@ static int __init mpls_init(void)
0);
rtnl_register(PF_MPLS, RTM_GETNETCONF, mpls_netconf_get_devconf,
mpls_netconf_dump_devconf, 0);
+ err = ipgre_tunnel_encap_add_mpls_ops();
+ if (err)
+ pr_err("Can't add mpls over gre tunnel ops\n");
+
err = 0;
out:
return err;
@@ -2502,6 +2537,7 @@ static void __exit mpls_exit(void)
dev_remove_pack(&mpls_packet_type);
unregister_netdevice_notifier(&mpls_dev_notifier);
unregister_pernet_subsys(&mpls_net_ops);
+ ipgre_tunnel_encap_del_mpls_ops();
}
module_exit(mpls_exit);