6 files changed, 470 insertions, 8 deletions

diff --git a/net/tipc/Kconfig b/net/tipc/Kconfig
index 91c8a8e031db..c25a3a149dc4 100644
--- a/net/tipc/Kconfig
+++ b/net/tipc/Kconfig
@@ -26,3 +26,11 @@ config TIPC_MEDIA_IB
         help
           Saying Y here will enable support for running TIPC on
           IP-over-InfiniBand devices.
+config TIPC_MEDIA_UDP
+        bool "IP/UDP media type support"
+        depends on TIPC
+        select NET_UDP_TUNNEL
+        help
+          Saying Y here will enable support for running TIPC over IP/UDP
+        bool
+        default y
diff --git a/net/tipc/Makefile b/net/tipc/Makefile
index 599b1a540d2b..57e460be4692 100644
--- a/net/tipc/Makefile
+++ b/net/tipc/Makefile
@@ -10,5 +10,6 @@ tipc-y	+= addr.o bcast.o bearer.o \
            netlink.o netlink_compat.o node.o socket.o eth_media.o \
            server.o socket.o
 
+tipc-$(CONFIG_TIPC_MEDIA_UDP)   += udp_media.o
 tipc-$(CONFIG_TIPC_MEDIA_IB)    += ib_media.o
 tipc-$(CONFIG_SYSCTL)           += sysctl.o
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index af6deeb397a8..840db89e4283 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -48,6 +48,9 @@ static struct tipc_media * const media_info_array[] = {
 #ifdef CONFIG_TIPC_MEDIA_IB
         &ib_media_info,
 #endif
+#ifdef CONFIG_TIPC_MEDIA_UDP
+        &udp_media_info,
+#endif
         NULL
 };
 
@@ -216,7 +219,8 @@ void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
  * tipc_enable_bearer - enable bearer with the given name
  */
 static int tipc_enable_bearer(struct net *net, const char *name,
-                              u32 disc_domain, u32 priority)
+                              u32 disc_domain, u32 priority,
+                              struct nlattr *attr[])
 {
         struct tipc_net *tn = net_generic(net, tipc_net_id);
         struct tipc_bearer *b_ptr;
@@ -304,7 +308,7 @@ restart:
 
         strcpy(b_ptr->name, name);
         b_ptr->media = m_ptr;
-        res = m_ptr->enable_media(net, b_ptr);
+        res = m_ptr->enable_media(net, b_ptr, attr);
         if (res) {
                 pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
                         name, -res);
@@ -372,7 +376,8 @@ static void bearer_disable(struct net *net, struct tipc_bearer *b_ptr,
         kfree_rcu(b_ptr, rcu);
 }
 
-int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b)
+int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
+                         struct nlattr *attr[])
 {
         struct net_device *dev;
         char *driver_name = strchr((const char *)b->name, ':') + 1;
@@ -791,7 +796,7 @@ int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
         }
 
         rtnl_lock();
-        err = tipc_enable_bearer(net, bearer, domain, prio);
+        err = tipc_enable_bearer(net, bearer, domain, prio, attrs);
         if (err) {
                 rtnl_unlock();
                 return err;
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 097aff08ad5b..5cad243ee8fc 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -41,7 +41,7 @@
 #include <net/genetlink.h>
 
 #define MAX_BEARERS     2
-#define MAX_MEDIA       2
+#define MAX_MEDIA       3
 #define MAX_NODES       4096
 #define WSIZE           32
 
@@ -59,6 +59,7 @@
  */
 #define TIPC_MEDIA_TYPE_ETH     1
 #define TIPC_MEDIA_TYPE_IB      2
+#define TIPC_MEDIA_TYPE_UDP     3
 
 /**
  * struct tipc_node_map - set of node identifiers
@@ -104,7 +105,8 @@ struct tipc_media {
         int (*send_msg)(struct net *net, struct sk_buff *buf,
                         struct tipc_bearer *b_ptr,
                         struct tipc_media_addr *dest);
-        int (*enable_media)(struct net *net, struct tipc_bearer *b_ptr);
+        int (*enable_media)(struct net *net, struct tipc_bearer *b_ptr,
+                            struct nlattr *attr[]);
         void (*disable_media)(struct tipc_bearer *b_ptr);
         int (*addr2str)(struct tipc_media_addr *addr,
                         char *strbuf,
@@ -183,6 +185,9 @@ extern struct tipc_media eth_media_info;
 #ifdef CONFIG_TIPC_MEDIA_IB
 extern struct tipc_media ib_media_info;
 #endif
+#ifdef CONFIG_TIPC_MEDIA_UDP
+extern struct tipc_media udp_media_info;
+#endif
 
 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info);
 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info);
@@ -197,7 +202,8 @@ int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info);
 int tipc_media_set_priority(const char *name, u32 new_value);
 int tipc_media_set_window(const char *name, u32 new_value);
 void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a);
-int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b);
+int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
+                         struct nlattr *attrs[]);
 void tipc_disable_l2_media(struct tipc_bearer *b);
 int tipc_l2_send_msg(struct net *net, struct sk_buff *buf,
                      struct tipc_bearer *b, struct tipc_media_addr *dest);
diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index c1cc8d7a5d52..fa167846d1ab 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -87,7 +87,7 @@ struct plist;
  * Note: Headroom should be a multiple of 4 to ensure the TIPC header fields
  *       are word aligned for quicker access
  */
-#define BUF_HEADROOM LL_MAX_HEADER
+#define BUF_HEADROOM (LL_MAX_HEADER + 48)
 
 struct tipc_skb_cb {
         void *handle;
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
new file mode 100644
index 000000000000..0d10001db40d
--- /dev/null
+++ b/net/tipc/udp_media.c
@@ -0,0 +1,442 @@
+/* net/tipc/udp_media.c: IP bearer support for TIPC
+ *
+ * Copyright (c) 2015, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/socket.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <linux/inet.h>
+#include <linux/inetdevice.h>
+#include <linux/igmp.h>
+#include <linux/kernel.h>
+#include <linux/workqueue.h>
+#include <linux/list.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/udp_tunnel.h>
+#include <linux/tipc_netlink.h>
+#include "core.h"
+#include "bearer.h"
+
+/* IANA assigned UDP port */
+#define UDP_PORT_DEFAULT        6118
+
+static const struct nla_policy tipc_nl_udp_policy[TIPC_NLA_UDP_MAX + 1] = {
+        [TIPC_NLA_UDP_UNSPEC]   = {.type = NLA_UNSPEC},
+        [TIPC_NLA_UDP_LOCAL]    = {.type = NLA_BINARY,
+                                   .len = sizeof(struct sockaddr_storage)},
+        [TIPC_NLA_UDP_REMOTE]   = {.type = NLA_BINARY,
+                                   .len = sizeof(struct sockaddr_storage)},
+};
+
+/**
+ * struct udp_media_addr - IP/UDP addressing information
+ *
+ * This is the bearer level originating address used in neighbor discovery
+ * messages, and all fields should be in network byte order
+ */
+struct udp_media_addr {
+        __be16  proto;
+        __be16  udp_port;
+        union {
+                struct in_addr ipv4;
+                struct in6_addr ipv6;
+        };
+};
+
+/**
+ * struct udp_bearer - ip/udp bearer data structure
+ * @bearer:     associated generic tipc bearer
+ * @ubsock:     bearer associated socket
+ * @ifindex:    local address scope
+ * @work:       used to schedule deferred work on a bearer
+ */
+struct udp_bearer {
+        struct tipc_bearer __rcu *bearer;
+        struct socket *ubsock;
+        u32 ifindex;
+        struct work_struct work;
+};
+
+/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
+static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
+                                    struct udp_media_addr *ua)
+{
+        memset(addr, 0, sizeof(struct tipc_media_addr));
+        addr->media_id = TIPC_MEDIA_TYPE_UDP;
+        memcpy(addr->value, ua, sizeof(struct udp_media_addr));
+        if (ntohs(ua->proto) == ETH_P_IP) {
+                if (ipv4_is_multicast(ua->ipv4.s_addr))
+                        addr->broadcast = 1;
+        } else if (ntohs(ua->proto) == ETH_P_IPV6) {
+                if (ipv6_addr_type(&ua->ipv6) & IPV6_ADDR_MULTICAST)
+                        addr->broadcast = 1;
+        } else {
+                pr_err("Invalid UDP media address\n");
+        }
+}
+
+/* tipc_udp_addr2str - convert ip/udp address to string */
+static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
+{
+        struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
+
+        if (ntohs(ua->proto) == ETH_P_IP)
+                snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->udp_port));
+        else if (ntohs(ua->proto) == ETH_P_IPV6)
+                snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->udp_port));
+        else
+                pr_err("Invalid UDP media address\n");
+        return 0;
+}
+
+/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
+static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
+                             char *msg)
+{
+        struct udp_media_addr *ua;
+
+        ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
+        if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
+                return -EINVAL;
+        tipc_udp_media_addr_set(a, ua);
+        return 0;
+}
+
+/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
+static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
+{
+        memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
+        msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
+        memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
+               sizeof(struct udp_media_addr));
+        return 0;
+}
+
+/* tipc_send_msg - enqueue a send request */
+static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
+                             struct tipc_bearer *b,
+                             struct tipc_media_addr *dest)
+{
+        int ttl, err = 0;
+        struct udp_bearer *ub;
+        struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value;
+        struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
+        struct sk_buff *clone;
+        struct rtable *rt;
+
+        clone = skb_clone(skb, GFP_ATOMIC);
+        skb_set_inner_protocol(clone, htons(ETH_P_TIPC));
+        ub = rcu_dereference_rtnl(b->media_ptr);
+        if (!ub) {
+                err = -ENODEV;
+                goto tx_error;
+        }
+        if (htons(dst->proto) == ETH_P_IP) {
+                struct flowi4 fl = {
+                        .daddr = dst->ipv4.s_addr,
+                        .saddr = src->ipv4.s_addr,
+                        .flowi4_mark = clone->mark,
+                        .flowi4_proto = IPPROTO_UDP
+                };
+                rt = ip_route_output_key(net, &fl);
+                if (IS_ERR(rt)) {
+                        err = PTR_ERR(rt);
+                        goto tx_error;
+                }
+                ttl = ip4_dst_hoplimit(&rt->dst);
+                err = udp_tunnel_xmit_skb(rt, clone, src->ipv4.s_addr,
+                                          dst->ipv4.s_addr, 0, ttl, 0,
+                                          src->udp_port, dst->udp_port,
+                                          false, true);
+                if (err < 0) {
+                        ip_rt_put(rt);
+                        goto tx_error;
+                }
+#if IS_ENABLED(CONFIG_IPV6)
+        } else {
+                struct dst_entry *ndst;
+                struct flowi6 fl6 = {
+                        .flowi6_oif = ub->ifindex,
+                        .daddr = dst->ipv6,
+                        .saddr = src->ipv6,
+                        .flowi6_proto = IPPROTO_UDP
+                };
+                err = ip6_dst_lookup(ub->ubsock->sk, &ndst, &fl6);
+                if (err)
+                        goto tx_error;
+                ttl = ip6_dst_hoplimit(ndst);
+                err = udp_tunnel6_xmit_skb(ndst, clone, ndst->dev, &src->ipv6,
+                                           &dst->ipv6, 0, ttl, src->udp_port,
+                                           dst->udp_port, false);
+#endif
+        }
+        return err;
+
+tx_error:
+        kfree_skb(clone);
+        return err;
+}
+
+/* tipc_udp_recv - read data from bearer socket */
+static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
+{
+        struct udp_bearer *ub;
+        struct tipc_bearer *b;
+
+        ub = rcu_dereference_sk_user_data(sk);
+        if (!ub) {
+                pr_err_ratelimited("Failed to get UDP bearer reference");
+                kfree_skb(skb);
+                return 0;
+        }
+
+        skb_pull(skb, sizeof(struct udphdr));
+        rcu_read_lock();
+        b = rcu_dereference_rtnl(ub->bearer);
+
+        if (b) {
+                tipc_rcv(sock_net(sk), skb, b);
+                rcu_read_unlock();
+                return 0;
+        }
+        rcu_read_unlock();
+        kfree_skb(skb);
+        return 0;
+}
+
+static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
+{
+        int err = 0;
+        struct ip_mreqn mreqn;
+        struct sock *sk = ub->ubsock->sk;
+
+        if (ntohs(remote->proto) == ETH_P_IP) {
+                if (!ipv4_is_multicast(remote->ipv4.s_addr))
+                        return 0;
+                mreqn.imr_multiaddr = remote->ipv4;
+                mreqn.imr_ifindex = ub->ifindex;
+                err = __ip_mc_join_group(sk, &mreqn);
+        } else {
+                if (!ipv6_addr_is_multicast(&remote->ipv6))
+                        return 0;
+                err = __ipv6_sock_mc_join(sk, ub->ifindex, &remote->ipv6);
+        }
+        return err;
+}
+
+/**
+ * parse_options - build local/remote addresses from configuration
+ * @attrs:      netlink config data
+ * @ub:         UDP bearer instance
+ * @local:      local bearer IP address/port
+ * @remote:     peer or multicast IP/port
+ */
+static int parse_options(struct nlattr *attrs[], struct udp_bearer *ub,
+                         struct udp_media_addr *local,
+                         struct udp_media_addr *remote)
+{
+        struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
+        struct sockaddr_storage *sa_local, *sa_remote;
+
+        if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
+                goto err;
+        if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX,
+                             attrs[TIPC_NLA_BEARER_UDP_OPTS],
+                             tipc_nl_udp_policy))
+                goto err;
+        if (opts[TIPC_NLA_UDP_LOCAL] && opts[TIPC_NLA_UDP_REMOTE]) {
+                sa_local = nla_data(opts[TIPC_NLA_UDP_LOCAL]);
+                sa_remote = nla_data(opts[TIPC_NLA_UDP_REMOTE]);
+        } else {
+err:
+                pr_err("Invalid UDP bearer configuration");
+                return -EINVAL;
+        }
+        if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET) {
+                struct sockaddr_in *ip4;
+
+                ip4 = (struct sockaddr_in *)sa_local;
+                local->proto = htons(ETH_P_IP);
+                local->udp_port = ip4->sin_port;
+                local->ipv4.s_addr = ip4->sin_addr.s_addr;
+
+                ip4 = (struct sockaddr_in *)sa_remote;
+                remote->proto = htons(ETH_P_IP);
+                remote->udp_port = ip4->sin_port;
+                remote->ipv4.s_addr = ip4->sin_addr.s_addr;
+                return 0;
+
+#if IS_ENABLED(CONFIG_IPV6)
+        } else if ((sa_local->ss_family & sa_remote->ss_family) == AF_INET6) {
+                struct sockaddr_in6 *ip6;
+
+                ip6 = (struct sockaddr_in6 *)sa_local;
+                local->proto = htons(ETH_P_IPV6);
+                local->udp_port = ip6->sin6_port;
+                local->ipv6 = ip6->sin6_addr;
+                ub->ifindex = ip6->sin6_scope_id;
+
+                ip6 = (struct sockaddr_in6 *)sa_remote;
+                remote->proto = htons(ETH_P_IPV6);
+                remote->udp_port = ip6->sin6_port;
+                remote->ipv6 = ip6->sin6_addr;
+                return 0;
+#endif
+        }
+        return -EADDRNOTAVAIL;
+}
+
+/**
+ * tipc_udp_enable - callback to create a new udp bearer instance
+ * @net:        network namespace
+ * @b:          pointer to generic tipc_bearer
+ * @attrs:      netlink bearer configuration
+ *
+ * validate the bearer parameters and initialize the udp bearer
+ * rtnl_lock should be held
+ */
+static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
+                           struct nlattr *attrs[])
+{
+        int err = -EINVAL;
+        struct udp_bearer *ub;
+        struct udp_media_addr *remote;
+        struct udp_media_addr local = {0};
+        struct udp_port_cfg udp_conf = {0};
+        struct udp_tunnel_sock_cfg tuncfg = {0};
+
+        ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
+        if (!ub)
+                return -ENOMEM;
+
+        remote = (struct udp_media_addr *)&b->bcast_addr.value;
+        memset(remote, 0, sizeof(struct udp_media_addr));
+        err = parse_options(attrs, ub, &local, remote);
+        if (err)
+                goto err;
+
+        b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
+        b->bcast_addr.broadcast = 1;
+        rcu_assign_pointer(b->media_ptr, ub);
+        rcu_assign_pointer(ub->bearer, b);
+        tipc_udp_media_addr_set(&b->addr, &local);
+        if (htons(local.proto) == ETH_P_IP) {
+                struct net_device *dev;
+
+                dev = __ip_dev_find(net, local.ipv4.s_addr, false);
+                if (!dev) {
+                        err = -ENODEV;
+                        goto err;
+                }
+                udp_conf.family = AF_INET;
+                udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
+                udp_conf.use_udp_checksums = false;
+                ub->ifindex = dev->ifindex;
+                b->mtu = dev->mtu - sizeof(struct iphdr)
+                        - sizeof(struct udphdr);
+#if IS_ENABLED(CONFIG_IPV6)
+        } else if (htons(local.proto) == ETH_P_IPV6) {
+                udp_conf.family = AF_INET6;
+                udp_conf.use_udp6_tx_checksums = true;
+                udp_conf.use_udp6_rx_checksums = true;
+                udp_conf.local_ip6 = in6addr_any;
+                b->mtu = 1280;
+#endif
+        } else {
+                err = -EAFNOSUPPORT;
+                goto err;
+        }
+        udp_conf.local_udp_port = local.udp_port;
+        err = udp_sock_create(net, &udp_conf, &ub->ubsock);
+        if (err)
+                goto err;
+        tuncfg.sk_user_data = ub;
+        tuncfg.encap_type = 1;
+        tuncfg.encap_rcv = tipc_udp_recv;
+        tuncfg.encap_destroy = NULL;
+        setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
+
+        if (enable_mcast(ub, remote))
+                goto err;
+        return 0;
+err:
+        kfree(ub);
+        return err;
+}
+
+/* cleanup_bearer - break the socket/bearer association */
+static void cleanup_bearer(struct work_struct *work)
+{
+        struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
+
+        if (ub->ubsock)
+                udp_tunnel_sock_release(ub->ubsock);
+        synchronize_net();
+        kfree(ub);
+}
+
+/* tipc_udp_disable - detach bearer from socket */
+static void tipc_udp_disable(struct tipc_bearer *b)
+{
+        struct udp_bearer *ub;
+
+        ub = rcu_dereference_rtnl(b->media_ptr);
+        if (!ub) {
+                pr_err("UDP bearer instance not found\n");
+                return;
+        }
+        if (ub->ubsock)
+                sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
+        RCU_INIT_POINTER(b->media_ptr, NULL);
+        RCU_INIT_POINTER(ub->bearer, NULL);
+
+        /* sock_release need to be done outside of rtnl lock */
+        INIT_WORK(&ub->work, cleanup_bearer);
+        schedule_work(&ub->work);
+}
+
+struct tipc_media udp_media_info = {
+        .send_msg       = tipc_udp_send_msg,
+        .enable_media   = tipc_udp_enable,
+        .disable_media  = tipc_udp_disable,
+        .addr2str       = tipc_udp_addr2str,
+        .addr2msg       = tipc_udp_addr2msg,
+        .msg2addr       = tipc_udp_msg2addr,
+        .priority       = TIPC_DEF_LINK_PRI,
+        .tolerance      = TIPC_DEF_LINK_TOL,
+        .window         = TIPC_DEF_LINK_WIN,
+        .type_id        = TIPC_MEDIA_TYPE_UDP,
+        .hwaddr_len     = 0,
+        .name           = "udp"
+};