1 // SPDX-License-Identifier: GPL-2.0
2 /* Bareudp: UDP tunnel encasulation for different Payload types like
4 * Copyright (c) 2019 Nokia, Inc.
5 * Authors: Martin Varghese, <martin.varghese@nokia.com>
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/etherdevice.h>
13 #include <linux/hash.h>
14 #include <net/dst_metadata.h>
15 #include <net/gro_cells.h>
16 #include <net/rtnetlink.h>
17 #include <net/protocol.h>
18 #include <net/ip6_tunnel.h>
19 #include <net/ip_tunnels.h>
20 #include <net/udp_tunnel.h>
21 #include <net/bareudp.h>
23 #define BAREUDP_BASE_HLEN sizeof(struct udphdr)
24 #define BAREUDP_IPV4_HLEN (sizeof(struct iphdr) + \
25 sizeof(struct udphdr))
26 #define BAREUDP_IPV6_HLEN (sizeof(struct ipv6hdr) + \
27 sizeof(struct udphdr))
29 static bool log_ecn_error = true;
30 module_param(log_ecn_error, bool, 0644);
31 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
33 /* per-network namespace private data for this module */
35 static unsigned int bareudp_net_id;
38 struct list_head bareudp_list;
45 bool multi_proto_mode;
48 /* Pseudo network device */
50 struct net *net; /* netns for packet i/o */
51 struct net_device *dev; /* netdev for bareudp tunnel */
55 bool multi_proto_mode;
56 struct socket __rcu *sock;
57 struct list_head next; /* bareudp node on namespace list */
58 struct gro_cells gro_cells;
61 static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
63 struct metadata_dst *tun_dst = NULL;
64 struct bareudp_dev *bareudp;
65 unsigned short family;
71 bareudp = rcu_dereference_sk_user_data(sk);
75 if (skb->protocol == htons(ETH_P_IP))
80 if (bareudp->ethertype == htons(ETH_P_IP)) {
83 if (skb_copy_bits(skb, BAREUDP_BASE_HLEN, &ipversion,
85 bareudp->dev->stats.rx_dropped++;
91 proto = htons(ETH_P_IP);
92 } else if (ipversion == 6 && bareudp->multi_proto_mode) {
93 proto = htons(ETH_P_IPV6);
95 bareudp->dev->stats.rx_dropped++;
98 } else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
99 struct iphdr *tunnel_hdr;
101 tunnel_hdr = (struct iphdr *)skb_network_header(skb);
102 if (tunnel_hdr->version == 4) {
103 if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
104 proto = bareudp->ethertype;
105 } else if (bareudp->multi_proto_mode &&
106 ipv4_is_multicast(tunnel_hdr->daddr)) {
107 proto = htons(ETH_P_MPLS_MC);
109 bareudp->dev->stats.rx_dropped++;
114 struct ipv6hdr *tunnel_hdr_v6;
116 tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
118 ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
119 if (!(addr_type & IPV6_ADDR_MULTICAST)) {
120 proto = bareudp->ethertype;
121 } else if (bareudp->multi_proto_mode &&
122 (addr_type & IPV6_ADDR_MULTICAST)) {
123 proto = htons(ETH_P_MPLS_MC);
125 bareudp->dev->stats.rx_dropped++;
130 proto = bareudp->ethertype;
133 if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
135 !net_eq(bareudp->net,
136 dev_net(bareudp->dev)))) {
137 bareudp->dev->stats.rx_dropped++;
140 tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
142 bareudp->dev->stats.rx_dropped++;
145 skb_dst_set(skb, &tun_dst->dst);
146 skb->dev = bareudp->dev;
147 oiph = skb_network_header(skb);
148 skb_reset_network_header(skb);
149 skb_reset_mac_header(skb);
151 if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
152 err = IP_ECN_decapsulate(oiph, skb);
154 err = IP6_ECN_decapsulate(oiph, skb);
158 if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
159 net_info_ratelimited("non-ECT from %pI4 "
161 &((struct iphdr *)oiph)->saddr,
162 ((struct iphdr *)oiph)->tos);
164 net_info_ratelimited("non-ECT from %pI6\n",
165 &((struct ipv6hdr *)oiph)->saddr);
168 ++bareudp->dev->stats.rx_frame_errors;
169 ++bareudp->dev->stats.rx_errors;
175 err = gro_cells_receive(&bareudp->gro_cells, skb);
176 if (likely(err == NET_RX_SUCCESS))
177 dev_sw_netstats_rx_add(bareudp->dev, len);
181 /* Consume bad packet */
187 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
192 static int bareudp_init(struct net_device *dev)
194 struct bareudp_dev *bareudp = netdev_priv(dev);
197 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
201 err = gro_cells_init(&bareudp->gro_cells, dev);
203 free_percpu(dev->tstats);
209 static void bareudp_uninit(struct net_device *dev)
211 struct bareudp_dev *bareudp = netdev_priv(dev);
213 gro_cells_destroy(&bareudp->gro_cells);
214 free_percpu(dev->tstats);
217 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
219 struct udp_port_cfg udp_conf;
223 memset(&udp_conf, 0, sizeof(udp_conf));
224 #if IS_ENABLED(CONFIG_IPV6)
225 udp_conf.family = AF_INET6;
227 udp_conf.family = AF_INET;
229 udp_conf.local_udp_port = port;
230 /* Open UDP socket */
231 err = udp_sock_create(net, &udp_conf, &sock);
235 udp_allow_gso(sock->sk);
239 /* Create new listen socket if needed */
240 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
242 struct udp_tunnel_sock_cfg tunnel_cfg;
245 sock = bareudp_create_sock(bareudp->net, port);
247 return PTR_ERR(sock);
249 /* Mark socket as an encapsulation socket */
250 memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
251 tunnel_cfg.sk_user_data = bareudp;
252 tunnel_cfg.encap_type = 1;
253 tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
254 tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
255 tunnel_cfg.encap_destroy = NULL;
256 setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
258 rcu_assign_pointer(bareudp->sock, sock);
262 static int bareudp_open(struct net_device *dev)
264 struct bareudp_dev *bareudp = netdev_priv(dev);
267 ret = bareudp_socket_create(bareudp, bareudp->port);
271 static void bareudp_sock_release(struct bareudp_dev *bareudp)
275 sock = bareudp->sock;
276 rcu_assign_pointer(bareudp->sock, NULL);
278 udp_tunnel_sock_release(sock);
281 static int bareudp_stop(struct net_device *dev)
283 struct bareudp_dev *bareudp = netdev_priv(dev);
285 bareudp_sock_release(bareudp);
289 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
290 struct bareudp_dev *bareudp,
291 const struct ip_tunnel_info *info)
293 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
294 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
295 struct socket *sock = rcu_dereference(bareudp->sock);
296 bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
297 const struct ip_tunnel_key *key = &info->key;
308 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
309 IPPROTO_UDP, use_cache);
314 skb_tunnel_check_pmtu(skb, &rt->dst,
315 BAREUDP_IPV4_HLEN + info->options_len, false);
317 sport = udp_flow_src_port(bareudp->net, skb,
318 bareudp->sport_min, USHRT_MAX,
320 tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
322 df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
323 skb_scrub_packet(skb, xnet);
326 if (!skb_pull(skb, skb_network_offset(skb)))
329 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
330 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
332 err = skb_cow_head(skb, min_headroom);
336 err = udp_tunnel_handle_offloads(skb, udp_sum);
340 skb_set_inner_protocol(skb, bareudp->ethertype);
341 udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
342 tos, ttl, df, sport, bareudp->port,
343 !net_eq(bareudp->net, dev_net(bareudp->dev)),
344 !(info->key.tun_flags & TUNNEL_CSUM));
348 dst_release(&rt->dst);
352 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
353 struct bareudp_dev *bareudp,
354 const struct ip_tunnel_info *info)
356 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
357 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
358 struct socket *sock = rcu_dereference(bareudp->sock);
359 bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
360 const struct ip_tunnel_key *key = &info->key;
361 struct dst_entry *dst = NULL;
362 struct in6_addr saddr, daddr;
371 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
372 IPPROTO_UDP, use_cache);
376 skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
379 sport = udp_flow_src_port(bareudp->net, skb,
380 bareudp->sport_min, USHRT_MAX,
382 prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
385 skb_scrub_packet(skb, xnet);
388 if (!skb_pull(skb, skb_network_offset(skb)))
391 min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
392 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
394 err = skb_cow_head(skb, min_headroom);
398 err = udp_tunnel_handle_offloads(skb, udp_sum);
402 daddr = info->key.u.ipv6.dst;
403 udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
404 &saddr, &daddr, prio, ttl,
405 info->key.label, sport, bareudp->port,
406 !(info->key.tun_flags & TUNNEL_CSUM));
414 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
416 if (bareudp->ethertype == proto)
419 if (!bareudp->multi_proto_mode)
422 if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
423 proto == htons(ETH_P_MPLS_MC))
426 if (bareudp->ethertype == htons(ETH_P_IP) &&
427 proto == htons(ETH_P_IPV6))
433 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
435 struct bareudp_dev *bareudp = netdev_priv(dev);
436 struct ip_tunnel_info *info = NULL;
439 if (!bareudp_proto_valid(bareudp, skb->protocol)) {
444 info = skb_tunnel_info(skb);
445 if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
451 if (IS_ENABLED(CONFIG_IPV6) && info->mode & IP_TUNNEL_INFO_IPV6)
452 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
454 err = bareudp_xmit_skb(skb, dev, bareudp, info);
464 dev->stats.collisions++;
465 else if (err == -ENETUNREACH)
466 dev->stats.tx_carrier_errors++;
468 dev->stats.tx_errors++;
472 static int bareudp_fill_metadata_dst(struct net_device *dev,
475 struct ip_tunnel_info *info = skb_tunnel_info(skb);
476 struct bareudp_dev *bareudp = netdev_priv(dev);
479 use_cache = ip_tunnel_dst_cache_usable(skb, info);
481 if (!IS_ENABLED(CONFIG_IPV6) || ip_tunnel_info_af(info) == AF_INET) {
485 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
486 info, IPPROTO_UDP, use_cache);
491 info->key.u.ipv4.src = saddr;
492 } else if (ip_tunnel_info_af(info) == AF_INET6) {
493 struct dst_entry *dst;
494 struct in6_addr saddr;
495 struct socket *sock = rcu_dereference(bareudp->sock);
497 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
498 &saddr, info, IPPROTO_UDP,
504 info->key.u.ipv6.src = saddr;
509 info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
512 info->key.tp_dst = bareudp->port;
516 static const struct net_device_ops bareudp_netdev_ops = {
517 .ndo_init = bareudp_init,
518 .ndo_uninit = bareudp_uninit,
519 .ndo_open = bareudp_open,
520 .ndo_stop = bareudp_stop,
521 .ndo_start_xmit = bareudp_xmit,
522 .ndo_get_stats64 = dev_get_tstats64,
523 .ndo_fill_metadata_dst = bareudp_fill_metadata_dst,
526 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
527 [IFLA_BAREUDP_PORT] = { .type = NLA_U16 },
528 [IFLA_BAREUDP_ETHERTYPE] = { .type = NLA_U16 },
529 [IFLA_BAREUDP_SRCPORT_MIN] = { .type = NLA_U16 },
530 [IFLA_BAREUDP_MULTIPROTO_MODE] = { .type = NLA_FLAG },
533 /* Info for udev, that this is a virtual tunnel endpoint */
534 static const struct device_type bareudp_type = {
538 /* Initialize the device structure. */
539 static void bareudp_setup(struct net_device *dev)
541 dev->netdev_ops = &bareudp_netdev_ops;
542 dev->needs_free_netdev = true;
543 SET_NETDEV_DEVTYPE(dev, &bareudp_type);
544 dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
545 dev->features |= NETIF_F_RXCSUM;
546 dev->features |= NETIF_F_LLTX;
547 dev->features |= NETIF_F_GSO_SOFTWARE;
548 dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
549 dev->hw_features |= NETIF_F_RXCSUM;
550 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
551 dev->hard_header_len = 0;
553 dev->mtu = ETH_DATA_LEN;
554 dev->min_mtu = IPV4_MIN_MTU;
555 dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
556 dev->type = ARPHRD_NONE;
558 dev->priv_flags |= IFF_NO_QUEUE;
559 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
562 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
563 struct netlink_ext_ack *extack)
566 NL_SET_ERR_MSG(extack,
567 "Not enough attributes provided to perform the operation");
573 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
574 struct netlink_ext_ack *extack)
576 memset(conf, 0, sizeof(*conf));
578 if (!data[IFLA_BAREUDP_PORT]) {
579 NL_SET_ERR_MSG(extack, "port not specified");
582 if (!data[IFLA_BAREUDP_ETHERTYPE]) {
583 NL_SET_ERR_MSG(extack, "ethertype not specified");
587 conf->port = nla_get_u16(data[IFLA_BAREUDP_PORT]);
588 conf->ethertype = nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
590 if (data[IFLA_BAREUDP_SRCPORT_MIN])
591 conf->sport_min = nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
593 if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
594 conf->multi_proto_mode = true;
599 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
600 const struct bareudp_conf *conf)
602 struct bareudp_dev *bareudp, *t = NULL;
604 list_for_each_entry(bareudp, &bn->bareudp_list, next) {
605 if (conf->port == bareudp->port)
611 static int bareudp_configure(struct net *net, struct net_device *dev,
612 struct bareudp_conf *conf,
613 struct netlink_ext_ack *extack)
615 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
616 struct bareudp_dev *t, *bareudp = netdev_priv(dev);
621 t = bareudp_find_dev(bn, conf);
623 NL_SET_ERR_MSG(extack, "Another bareudp device using the same port already exists");
627 if (conf->multi_proto_mode &&
628 (conf->ethertype != htons(ETH_P_MPLS_UC) &&
629 conf->ethertype != htons(ETH_P_IP))) {
630 NL_SET_ERR_MSG(extack, "Cannot set multiproto mode for this ethertype (only IPv4 and unicast MPLS are supported)");
634 bareudp->port = conf->port;
635 bareudp->ethertype = conf->ethertype;
636 bareudp->sport_min = conf->sport_min;
637 bareudp->multi_proto_mode = conf->multi_proto_mode;
639 err = register_netdevice(dev);
643 list_add(&bareudp->next, &bn->bareudp_list);
647 static int bareudp_link_config(struct net_device *dev,
653 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
660 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
662 struct bareudp_dev *bareudp = netdev_priv(dev);
664 list_del(&bareudp->next);
665 unregister_netdevice_queue(dev, head);
668 static int bareudp_newlink(struct net *net, struct net_device *dev,
669 struct nlattr *tb[], struct nlattr *data[],
670 struct netlink_ext_ack *extack)
672 struct bareudp_conf conf;
675 err = bareudp2info(data, &conf, extack);
679 err = bareudp_configure(net, dev, &conf, extack);
683 err = bareudp_link_config(dev, tb);
690 bareudp_dellink(dev, NULL);
694 static size_t bareudp_get_size(const struct net_device *dev)
696 return nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_PORT */
697 nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_ETHERTYPE */
698 nla_total_size(sizeof(__u16)) + /* IFLA_BAREUDP_SRCPORT_MIN */
699 nla_total_size(0) + /* IFLA_BAREUDP_MULTIPROTO_MODE */
703 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
705 struct bareudp_dev *bareudp = netdev_priv(dev);
707 if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
708 goto nla_put_failure;
709 if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
710 goto nla_put_failure;
711 if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
712 goto nla_put_failure;
713 if (bareudp->multi_proto_mode &&
714 nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
715 goto nla_put_failure;
723 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
725 .maxtype = IFLA_BAREUDP_MAX,
726 .policy = bareudp_policy,
727 .priv_size = sizeof(struct bareudp_dev),
728 .setup = bareudp_setup,
729 .validate = bareudp_validate,
730 .newlink = bareudp_newlink,
731 .dellink = bareudp_dellink,
732 .get_size = bareudp_get_size,
733 .fill_info = bareudp_fill_info,
736 static __net_init int bareudp_init_net(struct net *net)
738 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
740 INIT_LIST_HEAD(&bn->bareudp_list);
744 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
746 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
747 struct bareudp_dev *bareudp, *next;
749 list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
750 unregister_netdevice_queue(bareudp->dev, head);
753 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
759 list_for_each_entry(net, net_list, exit_list)
760 bareudp_destroy_tunnels(net, &list);
762 /* unregister the devices gathered above */
763 unregister_netdevice_many(&list);
767 static struct pernet_operations bareudp_net_ops = {
768 .init = bareudp_init_net,
769 .exit_batch = bareudp_exit_batch_net,
770 .id = &bareudp_net_id,
771 .size = sizeof(struct bareudp_net),
774 static int __init bareudp_init_module(void)
778 rc = register_pernet_subsys(&bareudp_net_ops);
782 rc = rtnl_link_register(&bareudp_link_ops);
788 unregister_pernet_subsys(&bareudp_net_ops);
792 late_initcall(bareudp_init_module);
794 static void __exit bareudp_cleanup_module(void)
796 rtnl_link_unregister(&bareudp_link_ops);
797 unregister_pernet_subsys(&bareudp_net_ops);
799 module_exit(bareudp_cleanup_module);
801 MODULE_ALIAS_RTNL_LINK("bareudp");
802 MODULE_LICENSE("GPL");
803 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
804 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");