tunnel: Bareudp Tunnel Support.

There are various L3 encapsulation standards using UDP being discussed to
leverage the UDP based load balancing capability of different networks.
MPLSoUDP (__ https://tools.ietf.org/html/rfc7510) is one among them.

The Bareudp tunnel provides a generic L3 encapsulation support for
tunnelling different L3 protocols like MPLS, IP, NSH etc. inside a UDP
tunnel.

An example to create bareudp device to tunnel MPLS traffic is
given

$ ovs-vsctl add-port br_mpls udp_port -- set interface udp_port \
             type=bareudp options:remote_ip=2.1.1.3
             options:local_ip=2.1.1.2 \
             options:payload_type=0x8847 options:dst_port=6635

The bareudp device supports special handling for MPLS & IP as
they can have multiple ethertypes. MPLS procotcol can have ethertypes
ETH_P_MPLS_UC (unicast) & ETH_P_MPLS_MC (multicast). IP protocol can have
ethertypes ETH_P_IP (v4) & ETH_P_IPV6 (v6).

The bareudp device to tunnel L3 traffic with multiple ethertypes
(MPLS & IP) can be created by passing the L3 protocol name as string in
the field payload_type. An example to create bareudp device to tunnel
MPLS unicast & multicast traffic is given below.::

$ ovs-vsctl add-port  br_mpls udp_port -- set interface
            udp_port \
            type=bareudp options:remote_ip=2.1.1.3
            options:local_ip=2.1.1.2 \
            options:payload_type=mpls options:dst_port=6635

Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-By: Greg Rose <gvrose8192@gmail.com>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/lib/dpif-netlink-rtnl.c b/lib/dpif-netlink-rtnl.c
index fd157ce2d..4fc42daed 100644
--- a/lib/dpif-netlink-rtnl.c
+++ b/lib/dpif-netlink-rtnl.c
@@ -58,6 +58,18 @@ VLOG_DEFINE_THIS_MODULE(dpif_netlink_rtnl);
 #define IFLA_GENEVE_UDP_ZERO_CSUM6_RX 10
 #endif
 
+#ifndef IFLA_BAREUDP_MAX
+#define IFLA_BAREUDP_MAX 0
+#endif
+#if IFLA_BAREUDP_MAX < 4
+#define IFLA_BAREUDP_PORT 1
+#define IFLA_BAREUDP_ETHERTYPE 2
+#define IFLA_BAREUDP_SRCPORT_MIN 3
+#define IFLA_BAREUDP_MULTIPROTO_MODE 4
+#endif
+
+#define BAREUDP_SRCPORT_MIN 49153
+
 static const struct nl_policy rtlink_policy[] = {
     [IFLA_LINKINFO] = { .type = NL_A_NESTED },
 };
@@ -81,6 +93,10 @@ static const struct nl_policy geneve_policy[] = {
     [IFLA_GENEVE_UDP_ZERO_CSUM6_RX] = { .type = NL_A_U8 },
     [IFLA_GENEVE_PORT] = { .type = NL_A_U16 },
 };
+static const struct nl_policy bareudp_policy[] = {
+    [IFLA_BAREUDP_PORT] = { .type = NL_A_U16 },
+    [IFLA_BAREUDP_ETHERTYPE] = { .type = NL_A_U16 },
+};
 
 static const char *
 vport_type_to_kind(enum ovs_vport_type type,
@@ -113,6 +129,8 @@ vport_type_to_kind(enum ovs_vport_type type,
         }
     case OVS_VPORT_TYPE_GTPU:
         return NULL;
+    case OVS_VPORT_TYPE_BAREUDP:
+        return "bareudp";
     case OVS_VPORT_TYPE_NETDEV:
     case OVS_VPORT_TYPE_INTERNAL:
     case OVS_VPORT_TYPE_LISP:
@@ -243,6 +261,24 @@ dpif_netlink_rtnl_geneve_verify(const struct netdev_tunnel_config *tnl_cfg,
 
     return err;
 }
+static int
+dpif_netlink_rtnl_bareudp_verify(const struct netdev_tunnel_config *tnl_cfg,
+                                const char *kind, struct ofpbuf *reply)
+{
+    struct nlattr *bareudp[ARRAY_SIZE(bareudp_policy)];
+    int err;
+
+    err = rtnl_policy_parse(kind, reply, bareudp_policy, bareudp,
+                            ARRAY_SIZE(bareudp_policy));
+    if (!err) {
+        if ((tnl_cfg->dst_port != nl_attr_get_be16(bareudp[IFLA_BAREUDP_PORT]))
+            || (tnl_cfg->payload_ethertype
+                != nl_attr_get_be16(bareudp[IFLA_BAREUDP_ETHERTYPE]))) {
+            err = EINVAL;
+        }
+    }
+    return err;
+}
 
 static int
 dpif_netlink_rtnl_verify(const struct netdev_tunnel_config *tnl_cfg,
@@ -275,6 +311,9 @@ dpif_netlink_rtnl_verify(const struct netdev_tunnel_config *tnl_cfg,
     case OVS_VPORT_TYPE_GENEVE:
         err = dpif_netlink_rtnl_geneve_verify(tnl_cfg, kind, reply);
         break;
+    case OVS_VPORT_TYPE_BAREUDP:
+        err = dpif_netlink_rtnl_bareudp_verify(tnl_cfg, kind, reply);
+        break;
     case OVS_VPORT_TYPE_NETDEV:
     case OVS_VPORT_TYPE_INTERNAL:
     case OVS_VPORT_TYPE_LISP:
@@ -357,6 +396,16 @@ dpif_netlink_rtnl_create(const struct netdev_tunnel_config *tnl_cfg,
         nl_msg_put_u8(&request, IFLA_GENEVE_UDP_ZERO_CSUM6_RX, 1);
         nl_msg_put_be16(&request, IFLA_GENEVE_PORT, tnl_cfg->dst_port);
         break;
+    case OVS_VPORT_TYPE_BAREUDP:
+        nl_msg_put_be16(&request, IFLA_BAREUDP_ETHERTYPE,
+                        tnl_cfg->payload_ethertype);
+        nl_msg_put_u16(&request, IFLA_BAREUDP_SRCPORT_MIN,
+                       BAREUDP_SRCPORT_MIN);
+        nl_msg_put_be16(&request, IFLA_BAREUDP_PORT, tnl_cfg->dst_port);
+        if (tnl_cfg->exts & (1 << OVS_BAREUDP_EXT_MULTIPROTO_MODE)) {
+            nl_msg_put_flag(&request, IFLA_BAREUDP_MULTIPROTO_MODE);
+        }
+        break;
     case OVS_VPORT_TYPE_NETDEV:
     case OVS_VPORT_TYPE_INTERNAL:
     case OVS_VPORT_TYPE_LISP:
@@ -470,6 +519,7 @@ dpif_netlink_rtnl_port_destroy(const char *name, const char *type)
     case OVS_VPORT_TYPE_ERSPAN:
     case OVS_VPORT_TYPE_IP6ERSPAN:
     case OVS_VPORT_TYPE_IP6GRE:
+    case OVS_VPORT_TYPE_BAREUDP:
         return dpif_netlink_rtnl_destroy(name);
     case OVS_VPORT_TYPE_NETDEV:
     case OVS_VPORT_TYPE_INTERNAL: