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authorMartin Varghese <martin.varghese@nokia.com>2020-02-24 10:57:50 +0530
committerDavid S. Miller <davem@davemloft.net>2020-02-24 13:31:42 -0800
commit571912c69f0ed731bd1e071ade9dc7ca4aa52065 (patch)
tree319a2ff693104702ebfc44cbf22cbfebc5000fba /drivers/net/bareudp.c
parent48851e9e802de3ede4ce81c3f7896c63e841adbc (diff)
net: UDP tunnel encapsulation module for tunnelling different protocols like MPLS, IP, NSH etc.
The Bareudp tunnel module provides a generic L3 encapsulation tunnelling module for tunnelling different protocols like MPLS, IP,NSH etc inside a UDP tunnel. Signed-off-by: Martin Varghese <martin.varghese@nokia.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/bareudp.c')
-rw-r--r--drivers/net/bareudp.c743
1 files changed, 743 insertions, 0 deletions
diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
new file mode 100644
index 000000000000..32518969139e
--- /dev/null
+++ b/drivers/net/bareudp.c
@@ -0,0 +1,743 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Bareudp: UDP tunnel encasulation for different Payload types like
+ * MPLS, NSH, IP, etc.
+ * Copyright (c) 2019 Nokia, Inc.
+ * Authors: Martin Varghese, <martin.varghese@nokia.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/etherdevice.h>
+#include <linux/hash.h>
+#include <net/dst_metadata.h>
+#include <net/gro_cells.h>
+#include <net/rtnetlink.h>
+#include <net/protocol.h>
+#include <net/ip6_tunnel.h>
+#include <net/ip_tunnels.h>
+#include <net/udp_tunnel.h>
+#include <net/bareudp.h>
+
+#define BAREUDP_BASE_HLEN sizeof(struct udphdr)
+#define BAREUDP_IPV4_HLEN (sizeof(struct iphdr) + \
+ sizeof(struct udphdr))
+#define BAREUDP_IPV6_HLEN (sizeof(struct ipv6hdr) + \
+ sizeof(struct udphdr))
+
+static bool log_ecn_error = true;
+module_param(log_ecn_error, bool, 0644);
+MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
+
+/* per-network namespace private data for this module */
+
+static unsigned int bareudp_net_id;
+
+struct bareudp_net {
+ struct list_head bareudp_list;
+};
+
+/* Pseudo network device */
+struct bareudp_dev {
+ struct net *net; /* netns for packet i/o */
+ struct net_device *dev; /* netdev for bareudp tunnel */
+ __be16 ethertype;
+ __be16 port;
+ u16 sport_min;
+ struct socket __rcu *sock;
+ struct list_head next; /* bareudp node on namespace list */
+ struct gro_cells gro_cells;
+};
+
+static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct metadata_dst *tun_dst = NULL;
+ struct pcpu_sw_netstats *stats;
+ struct bareudp_dev *bareudp;
+ unsigned short family;
+ unsigned int len;
+ __be16 proto;
+ void *oiph;
+ int err;
+
+ bareudp = rcu_dereference_sk_user_data(sk);
+ if (!bareudp)
+ goto drop;
+
+ if (skb->protocol == htons(ETH_P_IP))
+ family = AF_INET;
+ else
+ family = AF_INET6;
+
+ proto = bareudp->ethertype;
+
+ if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
+ proto,
+ !net_eq(bareudp->net,
+ dev_net(bareudp->dev)))) {
+ bareudp->dev->stats.rx_dropped++;
+ goto drop;
+ }
+
+ tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
+ if (!tun_dst) {
+ bareudp->dev->stats.rx_dropped++;
+ goto drop;
+ }
+ skb_dst_set(skb, &tun_dst->dst);
+ skb->dev = bareudp->dev;
+ oiph = skb_network_header(skb);
+ skb_reset_network_header(skb);
+
+ if (family == AF_INET)
+ err = IP_ECN_decapsulate(oiph, skb);
+#if IS_ENABLED(CONFIG_IPV6)
+ else
+ err = IP6_ECN_decapsulate(oiph, skb);
+#endif
+
+ if (unlikely(err)) {
+ if (log_ecn_error) {
+ if (family == AF_INET)
+ net_info_ratelimited("non-ECT from %pI4 "
+ "with TOS=%#x\n",
+ &((struct iphdr *)oiph)->saddr,
+ ((struct iphdr *)oiph)->tos);
+#if IS_ENABLED(CONFIG_IPV6)
+ else
+ net_info_ratelimited("non-ECT from %pI6\n",
+ &((struct ipv6hdr *)oiph)->saddr);
+#endif
+ }
+ if (err > 1) {
+ ++bareudp->dev->stats.rx_frame_errors;
+ ++bareudp->dev->stats.rx_errors;
+ goto drop;
+ }
+ }
+
+ len = skb->len;
+ err = gro_cells_receive(&bareudp->gro_cells, skb);
+ if (likely(err == NET_RX_SUCCESS)) {
+ stats = this_cpu_ptr(bareudp->dev->tstats);
+ u64_stats_update_begin(&stats->syncp);
+ stats->rx_packets++;
+ stats->rx_bytes += len;
+ u64_stats_update_end(&stats->syncp);
+ }
+ return 0;
+drop:
+ /* Consume bad packet */
+ kfree_skb(skb);
+
+ return 0;
+}
+
+static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
+{
+ return 0;
+}
+
+static int bareudp_init(struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+ int err;
+
+ dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
+ if (!dev->tstats)
+ return -ENOMEM;
+
+ err = gro_cells_init(&bareudp->gro_cells, dev);
+ if (err) {
+ free_percpu(dev->tstats);
+ return err;
+ }
+ return 0;
+}
+
+static void bareudp_uninit(struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+
+ gro_cells_destroy(&bareudp->gro_cells);
+ free_percpu(dev->tstats);
+}
+
+static struct socket *bareudp_create_sock(struct net *net, __be16 port)
+{
+ struct udp_port_cfg udp_conf;
+ struct socket *sock;
+ int err;
+
+ memset(&udp_conf, 0, sizeof(udp_conf));
+#if IS_ENABLED(CONFIG_IPV6)
+ udp_conf.family = AF_INET6;
+#else
+ udp_conf.family = AF_INET;
+#endif
+ udp_conf.local_udp_port = port;
+ /* Open UDP socket */
+ err = udp_sock_create(net, &udp_conf, &sock);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ return sock;
+}
+
+/* Create new listen socket if needed */
+static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
+{
+ struct udp_tunnel_sock_cfg tunnel_cfg;
+ struct socket *sock;
+
+ sock = bareudp_create_sock(bareudp->net, port);
+ if (IS_ERR(sock))
+ return PTR_ERR(sock);
+
+ /* Mark socket as an encapsulation socket */
+ memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
+ tunnel_cfg.sk_user_data = bareudp;
+ tunnel_cfg.encap_type = 1;
+ tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
+ tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
+ tunnel_cfg.encap_destroy = NULL;
+ setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
+
+ if (sock->sk->sk_family == AF_INET6)
+ udp_encap_enable();
+
+ rcu_assign_pointer(bareudp->sock, sock);
+ return 0;
+}
+
+static int bareudp_open(struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+ int ret = 0;
+
+ ret = bareudp_socket_create(bareudp, bareudp->port);
+ return ret;
+}
+
+static void bareudp_sock_release(struct bareudp_dev *bareudp)
+{
+ struct socket *sock;
+
+ sock = bareudp->sock;
+ rcu_assign_pointer(bareudp->sock, NULL);
+ synchronize_net();
+ udp_tunnel_sock_release(sock);
+}
+
+static int bareudp_stop(struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+
+ bareudp_sock_release(bareudp);
+ return 0;
+}
+
+static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
+ struct bareudp_dev *bareudp,
+ const struct ip_tunnel_info *info)
+{
+ bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
+ bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
+ struct socket *sock = rcu_dereference(bareudp->sock);
+ bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
+ const struct ip_tunnel_key *key = &info->key;
+ struct rtable *rt;
+ __be16 sport, df;
+ int min_headroom;
+ __u8 tos, ttl;
+ __be32 saddr;
+ int err;
+
+ if (!sock)
+ return -ESHUTDOWN;
+
+ rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
+ IPPROTO_UDP, use_cache);
+
+ if (IS_ERR(rt))
+ return PTR_ERR(rt);
+
+ skb_tunnel_check_pmtu(skb, &rt->dst,
+ BAREUDP_IPV4_HLEN + info->options_len);
+
+ sport = udp_flow_src_port(bareudp->net, skb,
+ bareudp->sport_min, USHRT_MAX,
+ true);
+ tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
+ ttl = key->ttl;
+ df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
+ skb_scrub_packet(skb, xnet);
+
+ if (!skb_pull(skb, skb_network_offset(skb)))
+ goto free_dst;
+
+ min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
+ BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
+
+ err = skb_cow_head(skb, min_headroom);
+ if (unlikely(err))
+ goto free_dst;
+
+ err = udp_tunnel_handle_offloads(skb, udp_sum);
+ if (err)
+ goto free_dst;
+
+ skb_set_inner_protocol(skb, bareudp->ethertype);
+ udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
+ tos, ttl, df, sport, bareudp->port,
+ !net_eq(bareudp->net, dev_net(bareudp->dev)),
+ !(info->key.tun_flags & TUNNEL_CSUM));
+ return 0;
+
+free_dst:
+ dst_release(&rt->dst);
+ return err;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
+ struct bareudp_dev *bareudp,
+ const struct ip_tunnel_info *info)
+{
+ bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
+ bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
+ struct socket *sock = rcu_dereference(bareudp->sock);
+ bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
+ const struct ip_tunnel_key *key = &info->key;
+ struct dst_entry *dst = NULL;
+ struct in6_addr saddr, daddr;
+ int min_headroom;
+ __u8 prio, ttl;
+ __be16 sport;
+ int err;
+
+ if (!sock)
+ return -ESHUTDOWN;
+
+ dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
+ IPPROTO_UDP, use_cache);
+ if (IS_ERR(dst))
+ return PTR_ERR(dst);
+
+ skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len);
+
+ sport = udp_flow_src_port(bareudp->net, skb,
+ bareudp->sport_min, USHRT_MAX,
+ true);
+ prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
+ ttl = key->ttl;
+
+ skb_scrub_packet(skb, xnet);
+
+ if (!skb_pull(skb, skb_network_offset(skb)))
+ goto free_dst;
+
+ min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
+ BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
+
+ err = skb_cow_head(skb, min_headroom);
+ if (unlikely(err))
+ goto free_dst;
+
+ err = udp_tunnel_handle_offloads(skb, udp_sum);
+ if (err)
+ goto free_dst;
+
+ daddr = info->key.u.ipv6.dst;
+ udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
+ &saddr, &daddr, prio, ttl,
+ info->key.label, sport, bareudp->port,
+ !(info->key.tun_flags & TUNNEL_CSUM));
+ return 0;
+
+free_dst:
+ dst_release(dst);
+ return err;
+}
+#endif
+
+static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+ struct ip_tunnel_info *info = NULL;
+ int err;
+
+ if (skb->protocol != bareudp->ethertype) {
+ err = -EINVAL;
+ goto tx_error;
+ }
+
+ info = skb_tunnel_info(skb);
+ if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
+ err = -EINVAL;
+ goto tx_error;
+ }
+
+ rcu_read_lock();
+#if IS_ENABLED(CONFIG_IPV6)
+ if (info->mode & IP_TUNNEL_INFO_IPV6)
+ err = bareudp6_xmit_skb(skb, dev, bareudp, info);
+ else
+#endif
+ err = bareudp_xmit_skb(skb, dev, bareudp, info);
+
+ rcu_read_unlock();
+
+ if (likely(!err))
+ return NETDEV_TX_OK;
+tx_error:
+ dev_kfree_skb(skb);
+
+ if (err == -ELOOP)
+ dev->stats.collisions++;
+ else if (err == -ENETUNREACH)
+ dev->stats.tx_carrier_errors++;
+
+ dev->stats.tx_errors++;
+ return NETDEV_TX_OK;
+}
+
+static int bareudp_fill_metadata_dst(struct net_device *dev,
+ struct sk_buff *skb)
+{
+ struct ip_tunnel_info *info = skb_tunnel_info(skb);
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+ bool use_cache;
+
+ use_cache = ip_tunnel_dst_cache_usable(skb, info);
+
+ if (ip_tunnel_info_af(info) == AF_INET) {
+ struct rtable *rt;
+ __be32 saddr;
+
+ rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
+ info, IPPROTO_UDP, use_cache);
+ if (IS_ERR(rt))
+ return PTR_ERR(rt);
+
+ ip_rt_put(rt);
+ info->key.u.ipv4.src = saddr;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (ip_tunnel_info_af(info) == AF_INET6) {
+ struct dst_entry *dst;
+ struct in6_addr saddr;
+ struct socket *sock = rcu_dereference(bareudp->sock);
+
+ dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
+ &saddr, info, IPPROTO_UDP,
+ use_cache);
+ if (IS_ERR(dst))
+ return PTR_ERR(dst);
+
+ dst_release(dst);
+ info->key.u.ipv6.src = saddr;
+#endif
+ } else {
+ return -EINVAL;
+ }
+
+ info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
+ bareudp->sport_min,
+ USHRT_MAX, true);
+ info->key.tp_dst = bareudp->port;
+ return 0;
+}
+
+static const struct net_device_ops bareudp_netdev_ops = {
+ .ndo_init = bareudp_init,
+ .ndo_uninit = bareudp_uninit,
+ .ndo_open = bareudp_open,
+ .ndo_stop = bareudp_stop,
+ .ndo_start_xmit = bareudp_xmit,
+ .ndo_get_stats64 = ip_tunnel_get_stats64,
+ .ndo_fill_metadata_dst = bareudp_fill_metadata_dst,
+};
+
+static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
+ [IFLA_BAREUDP_PORT] = { .type = NLA_U16 },
+ [IFLA_BAREUDP_ETHERTYPE] = { .type = NLA_U16 },
+ [IFLA_BAREUDP_SRCPORT_MIN] = { .type = NLA_U16 },
+};
+
+/* Info for udev, that this is a virtual tunnel endpoint */
+static struct device_type bareudp_type = {
+ .name = "bareudp",
+};
+
+/* Initialize the device structure. */
+static void bareudp_setup(struct net_device *dev)
+{
+ dev->netdev_ops = &bareudp_netdev_ops;
+ dev->needs_free_netdev = true;
+ SET_NETDEV_DEVTYPE(dev, &bareudp_type);
+ dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
+ dev->features |= NETIF_F_RXCSUM;
+ dev->features |= NETIF_F_GSO_SOFTWARE;
+ dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
+ dev->hw_features |= NETIF_F_GSO_SOFTWARE;
+ dev->hard_header_len = 0;
+ dev->addr_len = 0;
+ dev->mtu = ETH_DATA_LEN;
+ dev->min_mtu = IPV4_MIN_MTU;
+ dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
+ dev->type = ARPHRD_NONE;
+ netif_keep_dst(dev);
+ dev->priv_flags |= IFF_NO_QUEUE;
+ dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+}
+
+static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ if (!data) {
+ NL_SET_ERR_MSG(extack,
+ "Not enough attributes provided to perform the operation");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf)
+{
+ if (!data[IFLA_BAREUDP_PORT] || !data[IFLA_BAREUDP_ETHERTYPE])
+ return -EINVAL;
+
+ if (data[IFLA_BAREUDP_PORT])
+ conf->port = nla_get_u16(data[IFLA_BAREUDP_PORT]);
+
+ if (data[IFLA_BAREUDP_ETHERTYPE])
+ conf->ethertype = nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
+
+ if (data[IFLA_BAREUDP_SRCPORT_MIN])
+ conf->sport_min = nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
+
+ return 0;
+}
+
+static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
+ const struct bareudp_conf *conf)
+{
+ struct bareudp_dev *bareudp, *t = NULL;
+
+ list_for_each_entry(bareudp, &bn->bareudp_list, next) {
+ if (conf->port == bareudp->port)
+ t = bareudp;
+ }
+ return t;
+}
+
+static int bareudp_configure(struct net *net, struct net_device *dev,
+ struct bareudp_conf *conf)
+{
+ struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+ struct bareudp_dev *t, *bareudp = netdev_priv(dev);
+ int err;
+
+ bareudp->net = net;
+ bareudp->dev = dev;
+ t = bareudp_find_dev(bn, conf);
+ if (t)
+ return -EBUSY;
+
+ bareudp->port = conf->port;
+ bareudp->ethertype = conf->ethertype;
+ bareudp->sport_min = conf->sport_min;
+ err = register_netdevice(dev);
+ if (err)
+ return err;
+
+ list_add(&bareudp->next, &bn->bareudp_list);
+ return 0;
+}
+
+static int bareudp_link_config(struct net_device *dev,
+ struct nlattr *tb[])
+{
+ int err;
+
+ if (tb[IFLA_MTU]) {
+ err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+static int bareudp_newlink(struct net *net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ struct bareudp_conf conf;
+ int err;
+
+ err = bareudp2info(data, &conf);
+ if (err)
+ return err;
+
+ err = bareudp_configure(net, dev, &conf);
+ if (err)
+ return err;
+
+ err = bareudp_link_config(dev, tb);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static void bareudp_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+
+ list_del(&bareudp->next);
+ unregister_netdevice_queue(dev, head);
+}
+
+static size_t bareudp_get_size(const struct net_device *dev)
+{
+ return nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_PORT */
+ nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_ETHERTYPE */
+ nla_total_size(sizeof(__u16)) + /* IFLA_BAREUDP_SRCPORT_MIN */
+ 0;
+}
+
+static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+ struct bareudp_dev *bareudp = netdev_priv(dev);
+
+ if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
+ goto nla_put_failure;
+ if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
+ goto nla_put_failure;
+ if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
+ goto nla_put_failure;
+
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
+ .kind = "bareudp",
+ .maxtype = IFLA_BAREUDP_MAX,
+ .policy = bareudp_policy,
+ .priv_size = sizeof(struct bareudp_dev),
+ .setup = bareudp_setup,
+ .validate = bareudp_validate,
+ .newlink = bareudp_newlink,
+ .dellink = bareudp_dellink,
+ .get_size = bareudp_get_size,
+ .fill_info = bareudp_fill_info,
+};
+
+struct net_device *bareudp_dev_create(struct net *net, const char *name,
+ u8 name_assign_type,
+ struct bareudp_conf *conf)
+{
+ struct nlattr *tb[IFLA_MAX + 1];
+ struct net_device *dev;
+ LIST_HEAD(list_kill);
+ int err;
+
+ memset(tb, 0, sizeof(tb));
+ dev = rtnl_create_link(net, name, name_assign_type,
+ &bareudp_link_ops, tb, NULL);
+ if (IS_ERR(dev))
+ return dev;
+
+ err = bareudp_configure(net, dev, conf);
+ if (err) {
+ free_netdev(dev);
+ return ERR_PTR(err);
+ }
+ err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
+ if (err)
+ goto err;
+
+ err = rtnl_configure_link(dev, NULL);
+ if (err < 0)
+ goto err;
+
+ return dev;
+err:
+ bareudp_dellink(dev, &list_kill);
+ unregister_netdevice_many(&list_kill);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(bareudp_dev_create);
+
+static __net_init int bareudp_init_net(struct net *net)
+{
+ struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+
+ INIT_LIST_HEAD(&bn->bareudp_list);
+ return 0;
+}
+
+static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
+{
+ struct bareudp_net *bn = net_generic(net, bareudp_net_id);
+ struct bareudp_dev *bareudp, *next;
+
+ list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
+ unregister_netdevice_queue(bareudp->dev, head);
+}
+
+static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
+{
+ struct net *net;
+ LIST_HEAD(list);
+
+ rtnl_lock();
+ list_for_each_entry(net, net_list, exit_list)
+ bareudp_destroy_tunnels(net, &list);
+
+ /* unregister the devices gathered above */
+ unregister_netdevice_many(&list);
+ rtnl_unlock();
+}
+
+static struct pernet_operations bareudp_net_ops = {
+ .init = bareudp_init_net,
+ .exit_batch = bareudp_exit_batch_net,
+ .id = &bareudp_net_id,
+ .size = sizeof(struct bareudp_net),
+};
+
+static int __init bareudp_init_module(void)
+{
+ int rc;
+
+ rc = register_pernet_subsys(&bareudp_net_ops);
+ if (rc)
+ goto out1;
+
+ rc = rtnl_link_register(&bareudp_link_ops);
+ if (rc)
+ goto out2;
+
+ return 0;
+out2:
+ unregister_pernet_subsys(&bareudp_net_ops);
+out1:
+ return rc;
+}
+late_initcall(bareudp_init_module);
+
+static void __exit bareudp_cleanup_module(void)
+{
+ rtnl_link_unregister(&bareudp_link_ops);
+ unregister_pernet_subsys(&bareudp_net_ops);
+}
+module_exit(bareudp_cleanup_module);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
+MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");