1 // SPDX-License-Identifier: GPL-2.0
2 /* Bareudp: UDP tunnel encasulation for different Payload types like
3 * MPLS, NSH, IP, etc.
4 * Copyright (c) 2019 Nokia, Inc.
5 * Authors: Martin Varghese, <martin.varghese@nokia.com>
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
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>
22
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))
28
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");
32
33 /* per-network namespace private data for this module */
34
35 static unsigned int bareudp_net_id;
36
37 struct bareudp_net {
38 struct list_head bareudp_list;
39 };
40
41 struct bareudp_conf {
42 __be16 ethertype;
43 __be16 port;
44 u16 sport_min;
45 bool multi_proto_mode;
46 };
47
48 /* Pseudo network device */
49 struct bareudp_dev {
50 struct net *net; /* netns for packet i/o */
51 struct net_device *dev; /* netdev for bareudp tunnel */
52 __be16 ethertype;
53 __be16 port;
54 u16 sport_min;
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;
59 };
60
bareudp_udp_encap_recv(struct sock * sk,struct sk_buff * skb)61 static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
62 {
63 struct metadata_dst *tun_dst = NULL;
64 struct bareudp_dev *bareudp;
65 unsigned short family;
66 unsigned int len;
67 __be16 proto;
68 void *oiph;
69 int err;
70 int nh;
71
72 bareudp = rcu_dereference_sk_user_data(sk);
73 if (!bareudp)
74 goto drop;
75
76 if (skb->protocol == htons(ETH_P_IP))
77 family = AF_INET;
78 else
79 family = AF_INET6;
80
81 if (bareudp->ethertype == htons(ETH_P_IP)) {
82 __u8 ipversion;
83
84 if (skb_copy_bits(skb, BAREUDP_BASE_HLEN, &ipversion,
85 sizeof(ipversion))) {
86 DEV_STATS_INC(bareudp->dev, rx_dropped);
87 goto drop;
88 }
89 ipversion >>= 4;
90
91 if (ipversion == 4) {
92 proto = htons(ETH_P_IP);
93 } else if (ipversion == 6 && bareudp->multi_proto_mode) {
94 proto = htons(ETH_P_IPV6);
95 } else {
96 DEV_STATS_INC(bareudp->dev, rx_dropped);
97 goto drop;
98 }
99 } else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
100 struct iphdr *tunnel_hdr;
101
102 tunnel_hdr = (struct iphdr *)skb_network_header(skb);
103 if (tunnel_hdr->version == 4) {
104 if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
105 proto = bareudp->ethertype;
106 } else if (bareudp->multi_proto_mode &&
107 ipv4_is_multicast(tunnel_hdr->daddr)) {
108 proto = htons(ETH_P_MPLS_MC);
109 } else {
110 DEV_STATS_INC(bareudp->dev, rx_dropped);
111 goto drop;
112 }
113 } else {
114 int addr_type;
115 struct ipv6hdr *tunnel_hdr_v6;
116
117 tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
118 addr_type =
119 ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
120 if (!(addr_type & IPV6_ADDR_MULTICAST)) {
121 proto = bareudp->ethertype;
122 } else if (bareudp->multi_proto_mode &&
123 (addr_type & IPV6_ADDR_MULTICAST)) {
124 proto = htons(ETH_P_MPLS_MC);
125 } else {
126 DEV_STATS_INC(bareudp->dev, rx_dropped);
127 goto drop;
128 }
129 }
130 } else {
131 proto = bareudp->ethertype;
132 }
133
134 if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
135 proto,
136 !net_eq(bareudp->net,
137 dev_net(bareudp->dev)))) {
138 DEV_STATS_INC(bareudp->dev, rx_dropped);
139 goto drop;
140 }
141 tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
142 if (!tun_dst) {
143 DEV_STATS_INC(bareudp->dev, rx_dropped);
144 goto drop;
145 }
146 skb_dst_set(skb, &tun_dst->dst);
147 skb->dev = bareudp->dev;
148 skb_reset_mac_header(skb);
149
150 /* Save offset of outer header relative to skb->head,
151 * because we are going to reset the network header to the inner header
152 * and might change skb->head.
153 */
154 nh = skb_network_header(skb) - skb->head;
155
156 skb_reset_network_header(skb);
157
158 if (!pskb_inet_may_pull(skb)) {
159 DEV_STATS_INC(bareudp->dev, rx_length_errors);
160 DEV_STATS_INC(bareudp->dev, rx_errors);
161 goto drop;
162 }
163
164 /* Get the outer header. */
165 oiph = skb->head + nh;
166
167 if (!ipv6_mod_enabled() || family == AF_INET)
168 err = IP_ECN_decapsulate(oiph, skb);
169 else
170 err = IP6_ECN_decapsulate(oiph, skb);
171
172 if (unlikely(err)) {
173 if (log_ecn_error) {
174 if (!ipv6_mod_enabled() || family == AF_INET)
175 net_info_ratelimited("non-ECT from %pI4 "
176 "with TOS=%#x\n",
177 &((struct iphdr *)oiph)->saddr,
178 ((struct iphdr *)oiph)->tos);
179 else
180 net_info_ratelimited("non-ECT from %pI6\n",
181 &((struct ipv6hdr *)oiph)->saddr);
182 }
183 if (err > 1) {
184 DEV_STATS_INC(bareudp->dev, rx_frame_errors);
185 DEV_STATS_INC(bareudp->dev, rx_errors);
186 goto drop;
187 }
188 }
189
190 len = skb->len;
191 err = gro_cells_receive(&bareudp->gro_cells, skb);
192 if (likely(err == NET_RX_SUCCESS))
193 dev_sw_netstats_rx_add(bareudp->dev, len);
194
195 return 0;
196 drop:
197 /* Consume bad packet */
198 kfree_skb(skb);
199
200 return 0;
201 }
202
bareudp_err_lookup(struct sock * sk,struct sk_buff * skb)203 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
204 {
205 return 0;
206 }
207
bareudp_init(struct net_device * dev)208 static int bareudp_init(struct net_device *dev)
209 {
210 struct bareudp_dev *bareudp = netdev_priv(dev);
211 int err;
212
213 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
214 if (!dev->tstats)
215 return -ENOMEM;
216
217 err = gro_cells_init(&bareudp->gro_cells, dev);
218 if (err) {
219 free_percpu(dev->tstats);
220 return err;
221 }
222 return 0;
223 }
224
bareudp_uninit(struct net_device * dev)225 static void bareudp_uninit(struct net_device *dev)
226 {
227 struct bareudp_dev *bareudp = netdev_priv(dev);
228
229 gro_cells_destroy(&bareudp->gro_cells);
230 free_percpu(dev->tstats);
231 }
232
bareudp_create_sock(struct net * net,__be16 port)233 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
234 {
235 struct udp_port_cfg udp_conf;
236 struct socket *sock;
237 int err;
238
239 memset(&udp_conf, 0, sizeof(udp_conf));
240
241 if (ipv6_mod_enabled())
242 udp_conf.family = AF_INET6;
243 else
244 udp_conf.family = AF_INET;
245
246 udp_conf.local_udp_port = port;
247 /* Open UDP socket */
248 err = udp_sock_create(net, &udp_conf, &sock);
249 if (err < 0)
250 return ERR_PTR(err);
251
252 udp_allow_gso(sock->sk);
253 return sock;
254 }
255
256 /* Create new listen socket if needed */
bareudp_socket_create(struct bareudp_dev * bareudp,__be16 port)257 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
258 {
259 struct udp_tunnel_sock_cfg tunnel_cfg;
260 struct socket *sock;
261
262 sock = bareudp_create_sock(bareudp->net, port);
263 if (IS_ERR(sock))
264 return PTR_ERR(sock);
265
266 /* Mark socket as an encapsulation socket */
267 memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
268 tunnel_cfg.sk_user_data = bareudp;
269 tunnel_cfg.encap_type = 1;
270 tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
271 tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
272 tunnel_cfg.encap_destroy = NULL;
273 setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
274
275 rcu_assign_pointer(bareudp->sock, sock);
276 return 0;
277 }
278
bareudp_open(struct net_device * dev)279 static int bareudp_open(struct net_device *dev)
280 {
281 struct bareudp_dev *bareudp = netdev_priv(dev);
282 int ret = 0;
283
284 ret = bareudp_socket_create(bareudp, bareudp->port);
285 return ret;
286 }
287
bareudp_sock_release(struct bareudp_dev * bareudp)288 static void bareudp_sock_release(struct bareudp_dev *bareudp)
289 {
290 struct socket *sock;
291
292 sock = bareudp->sock;
293 rcu_assign_pointer(bareudp->sock, NULL);
294 synchronize_net();
295 udp_tunnel_sock_release(sock);
296 }
297
bareudp_stop(struct net_device * dev)298 static int bareudp_stop(struct net_device *dev)
299 {
300 struct bareudp_dev *bareudp = netdev_priv(dev);
301
302 bareudp_sock_release(bareudp);
303 return 0;
304 }
305
bareudp_xmit_skb(struct sk_buff * skb,struct net_device * dev,struct bareudp_dev * bareudp,const struct ip_tunnel_info * info)306 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
307 struct bareudp_dev *bareudp,
308 const struct ip_tunnel_info *info)
309 {
310 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
311 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
312 struct socket *sock = rcu_dereference(bareudp->sock);
313 bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
314 const struct ip_tunnel_key *key = &info->key;
315 struct rtable *rt;
316 __be16 sport, df;
317 int min_headroom;
318 __u8 tos, ttl;
319 __be32 saddr;
320 int err;
321
322 if (!skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
323 return -EINVAL;
324
325 if (!sock)
326 return -ESHUTDOWN;
327
328 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
329 IPPROTO_UDP, use_cache);
330
331 if (IS_ERR(rt))
332 return PTR_ERR(rt);
333
334 skb_tunnel_check_pmtu(skb, &rt->dst,
335 BAREUDP_IPV4_HLEN + info->options_len, false);
336
337 sport = udp_flow_src_port(bareudp->net, skb,
338 bareudp->sport_min, USHRT_MAX,
339 true);
340 tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
341 ttl = key->ttl;
342 df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
343 skb_scrub_packet(skb, xnet);
344
345 err = -ENOSPC;
346 if (!skb_pull(skb, skb_network_offset(skb)))
347 goto free_dst;
348
349 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
350 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
351
352 err = skb_cow_head(skb, min_headroom);
353 if (unlikely(err))
354 goto free_dst;
355
356 err = udp_tunnel_handle_offloads(skb, udp_sum);
357 if (err)
358 goto free_dst;
359
360 skb_set_inner_protocol(skb, bareudp->ethertype);
361 udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
362 tos, ttl, df, sport, bareudp->port,
363 !net_eq(bareudp->net, dev_net(bareudp->dev)),
364 !(info->key.tun_flags & TUNNEL_CSUM));
365 return 0;
366
367 free_dst:
368 dst_release(&rt->dst);
369 return err;
370 }
371
bareudp6_xmit_skb(struct sk_buff * skb,struct net_device * dev,struct bareudp_dev * bareudp,const struct ip_tunnel_info * info)372 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
373 struct bareudp_dev *bareudp,
374 const struct ip_tunnel_info *info)
375 {
376 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
377 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
378 struct socket *sock = rcu_dereference(bareudp->sock);
379 bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
380 const struct ip_tunnel_key *key = &info->key;
381 struct dst_entry *dst = NULL;
382 struct in6_addr saddr, daddr;
383 int min_headroom;
384 __u8 prio, ttl;
385 __be16 sport;
386 int err;
387
388 if (!skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
389 return -EINVAL;
390
391 if (!sock)
392 return -ESHUTDOWN;
393
394 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
395 IPPROTO_UDP, use_cache);
396 if (IS_ERR(dst))
397 return PTR_ERR(dst);
398
399 skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
400 false);
401
402 sport = udp_flow_src_port(bareudp->net, skb,
403 bareudp->sport_min, USHRT_MAX,
404 true);
405 prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
406 ttl = key->ttl;
407
408 skb_scrub_packet(skb, xnet);
409
410 err = -ENOSPC;
411 if (!skb_pull(skb, skb_network_offset(skb)))
412 goto free_dst;
413
414 min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
415 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
416
417 err = skb_cow_head(skb, min_headroom);
418 if (unlikely(err))
419 goto free_dst;
420
421 err = udp_tunnel_handle_offloads(skb, udp_sum);
422 if (err)
423 goto free_dst;
424
425 daddr = info->key.u.ipv6.dst;
426 udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
427 &saddr, &daddr, prio, ttl,
428 info->key.label, sport, bareudp->port,
429 !(info->key.tun_flags & TUNNEL_CSUM));
430 return 0;
431
432 free_dst:
433 dst_release(dst);
434 return err;
435 }
436
bareudp_proto_valid(struct bareudp_dev * bareudp,__be16 proto)437 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
438 {
439 if (bareudp->ethertype == proto)
440 return true;
441
442 if (!bareudp->multi_proto_mode)
443 return false;
444
445 if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
446 proto == htons(ETH_P_MPLS_MC))
447 return true;
448
449 if (bareudp->ethertype == htons(ETH_P_IP) &&
450 proto == htons(ETH_P_IPV6))
451 return true;
452
453 return false;
454 }
455
bareudp_xmit(struct sk_buff * skb,struct net_device * dev)456 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
457 {
458 struct bareudp_dev *bareudp = netdev_priv(dev);
459 struct ip_tunnel_info *info = NULL;
460 int err;
461
462 if (!bareudp_proto_valid(bareudp, skb->protocol)) {
463 err = -EINVAL;
464 goto tx_error;
465 }
466
467 info = skb_tunnel_info(skb);
468 if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
469 err = -EINVAL;
470 goto tx_error;
471 }
472
473 rcu_read_lock();
474 if (ipv6_mod_enabled() && info->mode & IP_TUNNEL_INFO_IPV6)
475 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
476 else
477 err = bareudp_xmit_skb(skb, dev, bareudp, info);
478
479 rcu_read_unlock();
480
481 if (likely(!err))
482 return NETDEV_TX_OK;
483 tx_error:
484 dev_kfree_skb(skb);
485
486 if (err == -ELOOP)
487 DEV_STATS_INC(dev, collisions);
488 else if (err == -ENETUNREACH)
489 DEV_STATS_INC(dev, tx_carrier_errors);
490
491 DEV_STATS_INC(dev, tx_errors);
492 return NETDEV_TX_OK;
493 }
494
bareudp_fill_metadata_dst(struct net_device * dev,struct sk_buff * skb)495 static int bareudp_fill_metadata_dst(struct net_device *dev,
496 struct sk_buff *skb)
497 {
498 struct ip_tunnel_info *info = skb_tunnel_info(skb);
499 struct bareudp_dev *bareudp = netdev_priv(dev);
500 bool use_cache;
501
502 use_cache = ip_tunnel_dst_cache_usable(skb, info);
503
504 if (!ipv6_mod_enabled() || ip_tunnel_info_af(info) == AF_INET) {
505 struct rtable *rt;
506 __be32 saddr;
507
508 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
509 info, IPPROTO_UDP, use_cache);
510 if (IS_ERR(rt))
511 return PTR_ERR(rt);
512
513 ip_rt_put(rt);
514 info->key.u.ipv4.src = saddr;
515 } else if (ip_tunnel_info_af(info) == AF_INET6) {
516 struct dst_entry *dst;
517 struct in6_addr saddr;
518 struct socket *sock = rcu_dereference(bareudp->sock);
519
520 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
521 &saddr, info, IPPROTO_UDP,
522 use_cache);
523 if (IS_ERR(dst))
524 return PTR_ERR(dst);
525
526 dst_release(dst);
527 info->key.u.ipv6.src = saddr;
528 } else {
529 return -EINVAL;
530 }
531
532 info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
533 bareudp->sport_min,
534 USHRT_MAX, true);
535 info->key.tp_dst = bareudp->port;
536 return 0;
537 }
538
539 static const struct net_device_ops bareudp_netdev_ops = {
540 .ndo_init = bareudp_init,
541 .ndo_uninit = bareudp_uninit,
542 .ndo_open = bareudp_open,
543 .ndo_stop = bareudp_stop,
544 .ndo_start_xmit = bareudp_xmit,
545 .ndo_get_stats64 = dev_get_tstats64,
546 .ndo_fill_metadata_dst = bareudp_fill_metadata_dst,
547 };
548
549 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
550 [IFLA_BAREUDP_PORT] = { .type = NLA_U16 },
551 [IFLA_BAREUDP_ETHERTYPE] = { .type = NLA_U16 },
552 [IFLA_BAREUDP_SRCPORT_MIN] = { .type = NLA_U16 },
553 [IFLA_BAREUDP_MULTIPROTO_MODE] = { .type = NLA_FLAG },
554 };
555
556 /* Info for udev, that this is a virtual tunnel endpoint */
557 static const struct device_type bareudp_type = {
558 .name = "bareudp",
559 };
560
561 /* Initialize the device structure. */
bareudp_setup(struct net_device * dev)562 static void bareudp_setup(struct net_device *dev)
563 {
564 dev->netdev_ops = &bareudp_netdev_ops;
565 dev->needs_free_netdev = true;
566 SET_NETDEV_DEVTYPE(dev, &bareudp_type);
567 dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
568 dev->features |= NETIF_F_RXCSUM;
569 dev->features |= NETIF_F_LLTX;
570 dev->features |= NETIF_F_GSO_SOFTWARE;
571 dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
572 dev->hw_features |= NETIF_F_RXCSUM;
573 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
574 dev->hard_header_len = 0;
575 dev->addr_len = 0;
576 dev->mtu = ETH_DATA_LEN;
577 dev->min_mtu = IPV4_MIN_MTU;
578 dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
579 dev->type = ARPHRD_NONE;
580 netif_keep_dst(dev);
581 dev->priv_flags |= IFF_NO_QUEUE;
582 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
583 }
584
bareudp_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)585 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
586 struct netlink_ext_ack *extack)
587 {
588 if (!data) {
589 NL_SET_ERR_MSG(extack,
590 "Not enough attributes provided to perform the operation");
591 return -EINVAL;
592 }
593 return 0;
594 }
595
bareudp2info(struct nlattr * data[],struct bareudp_conf * conf,struct netlink_ext_ack * extack)596 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
597 struct netlink_ext_ack *extack)
598 {
599 memset(conf, 0, sizeof(*conf));
600
601 if (!data[IFLA_BAREUDP_PORT]) {
602 NL_SET_ERR_MSG(extack, "port not specified");
603 return -EINVAL;
604 }
605 if (!data[IFLA_BAREUDP_ETHERTYPE]) {
606 NL_SET_ERR_MSG(extack, "ethertype not specified");
607 return -EINVAL;
608 }
609
610 conf->port = nla_get_u16(data[IFLA_BAREUDP_PORT]);
611 conf->ethertype = nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
612
613 if (data[IFLA_BAREUDP_SRCPORT_MIN])
614 conf->sport_min = nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
615
616 if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
617 conf->multi_proto_mode = true;
618
619 return 0;
620 }
621
bareudp_find_dev(struct bareudp_net * bn,const struct bareudp_conf * conf)622 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
623 const struct bareudp_conf *conf)
624 {
625 struct bareudp_dev *bareudp, *t = NULL;
626
627 list_for_each_entry(bareudp, &bn->bareudp_list, next) {
628 if (conf->port == bareudp->port)
629 t = bareudp;
630 }
631 return t;
632 }
633
bareudp_configure(struct net * net,struct net_device * dev,struct bareudp_conf * conf,struct netlink_ext_ack * extack)634 static int bareudp_configure(struct net *net, struct net_device *dev,
635 struct bareudp_conf *conf,
636 struct netlink_ext_ack *extack)
637 {
638 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
639 struct bareudp_dev *t, *bareudp = netdev_priv(dev);
640 int err;
641
642 bareudp->net = net;
643 bareudp->dev = dev;
644 t = bareudp_find_dev(bn, conf);
645 if (t) {
646 NL_SET_ERR_MSG(extack, "Another bareudp device using the same port already exists");
647 return -EBUSY;
648 }
649
650 if (conf->multi_proto_mode &&
651 (conf->ethertype != htons(ETH_P_MPLS_UC) &&
652 conf->ethertype != htons(ETH_P_IP))) {
653 NL_SET_ERR_MSG(extack, "Cannot set multiproto mode for this ethertype (only IPv4 and unicast MPLS are supported)");
654 return -EINVAL;
655 }
656
657 bareudp->port = conf->port;
658 bareudp->ethertype = conf->ethertype;
659 bareudp->sport_min = conf->sport_min;
660 bareudp->multi_proto_mode = conf->multi_proto_mode;
661
662 err = register_netdevice(dev);
663 if (err)
664 return err;
665
666 list_add(&bareudp->next, &bn->bareudp_list);
667 return 0;
668 }
669
bareudp_link_config(struct net_device * dev,struct nlattr * tb[])670 static int bareudp_link_config(struct net_device *dev,
671 struct nlattr *tb[])
672 {
673 int err;
674
675 if (tb[IFLA_MTU]) {
676 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
677 if (err)
678 return err;
679 }
680 return 0;
681 }
682
bareudp_dellink(struct net_device * dev,struct list_head * head)683 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
684 {
685 struct bareudp_dev *bareudp = netdev_priv(dev);
686
687 list_del(&bareudp->next);
688 unregister_netdevice_queue(dev, head);
689 }
690
bareudp_newlink(struct net * net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)691 static int bareudp_newlink(struct net *net, struct net_device *dev,
692 struct nlattr *tb[], struct nlattr *data[],
693 struct netlink_ext_ack *extack)
694 {
695 struct bareudp_conf conf;
696 int err;
697
698 err = bareudp2info(data, &conf, extack);
699 if (err)
700 return err;
701
702 err = bareudp_configure(net, dev, &conf, extack);
703 if (err)
704 return err;
705
706 err = bareudp_link_config(dev, tb);
707 if (err)
708 goto err_unconfig;
709
710 return 0;
711
712 err_unconfig:
713 bareudp_dellink(dev, NULL);
714 return err;
715 }
716
bareudp_get_size(const struct net_device * dev)717 static size_t bareudp_get_size(const struct net_device *dev)
718 {
719 return nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_PORT */
720 nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_ETHERTYPE */
721 nla_total_size(sizeof(__u16)) + /* IFLA_BAREUDP_SRCPORT_MIN */
722 nla_total_size(0) + /* IFLA_BAREUDP_MULTIPROTO_MODE */
723 0;
724 }
725
bareudp_fill_info(struct sk_buff * skb,const struct net_device * dev)726 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
727 {
728 struct bareudp_dev *bareudp = netdev_priv(dev);
729
730 if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
731 goto nla_put_failure;
732 if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
733 goto nla_put_failure;
734 if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
735 goto nla_put_failure;
736 if (bareudp->multi_proto_mode &&
737 nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
738 goto nla_put_failure;
739
740 return 0;
741
742 nla_put_failure:
743 return -EMSGSIZE;
744 }
745
746 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
747 .kind = "bareudp",
748 .maxtype = IFLA_BAREUDP_MAX,
749 .policy = bareudp_policy,
750 .priv_size = sizeof(struct bareudp_dev),
751 .setup = bareudp_setup,
752 .validate = bareudp_validate,
753 .newlink = bareudp_newlink,
754 .dellink = bareudp_dellink,
755 .get_size = bareudp_get_size,
756 .fill_info = bareudp_fill_info,
757 };
758
bareudp_init_net(struct net * net)759 static __net_init int bareudp_init_net(struct net *net)
760 {
761 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
762
763 INIT_LIST_HEAD(&bn->bareudp_list);
764 return 0;
765 }
766
bareudp_destroy_tunnels(struct net * net,struct list_head * head)767 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
768 {
769 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
770 struct bareudp_dev *bareudp, *next;
771
772 list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
773 unregister_netdevice_queue(bareudp->dev, head);
774 }
775
bareudp_exit_batch_net(struct list_head * net_list)776 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
777 {
778 struct net *net;
779 LIST_HEAD(list);
780
781 rtnl_lock();
782 list_for_each_entry(net, net_list, exit_list)
783 bareudp_destroy_tunnels(net, &list);
784
785 /* unregister the devices gathered above */
786 unregister_netdevice_many(&list);
787 rtnl_unlock();
788 }
789
790 static struct pernet_operations bareudp_net_ops = {
791 .init = bareudp_init_net,
792 .exit_batch = bareudp_exit_batch_net,
793 .id = &bareudp_net_id,
794 .size = sizeof(struct bareudp_net),
795 };
796
bareudp_init_module(void)797 static int __init bareudp_init_module(void)
798 {
799 int rc;
800
801 rc = register_pernet_subsys(&bareudp_net_ops);
802 if (rc)
803 goto out1;
804
805 rc = rtnl_link_register(&bareudp_link_ops);
806 if (rc)
807 goto out2;
808
809 return 0;
810 out2:
811 unregister_pernet_subsys(&bareudp_net_ops);
812 out1:
813 return rc;
814 }
815 late_initcall(bareudp_init_module);
816
bareudp_cleanup_module(void)817 static void __exit bareudp_cleanup_module(void)
818 {
819 rtnl_link_unregister(&bareudp_link_ops);
820 unregister_pernet_subsys(&bareudp_net_ops);
821 }
822 module_exit(bareudp_cleanup_module);
823
824 MODULE_ALIAS_RTNL_LINK("bareudp");
825 MODULE_LICENSE("GPL");
826 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
827 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");
828