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 IP_TUNNEL_DECLARE_FLAGS(key) = { };
65 struct bareudp_dev *bareudp;
66 unsigned short family;
67 unsigned int len;
68 __be16 proto;
69 void *oiph;
70 int err;
71 int nh;
72
73 bareudp = rcu_dereference_sk_user_data(sk);
74 if (!bareudp)
75 goto drop;
76
77 if (skb->protocol == htons(ETH_P_IP))
78 family = AF_INET;
79 else
80 family = AF_INET6;
81
82 if (bareudp->ethertype == htons(ETH_P_IP)) {
83 __u8 ipversion;
84
85 if (skb_copy_bits(skb, BAREUDP_BASE_HLEN, &ipversion,
86 sizeof(ipversion))) {
87 dev_dstats_rx_dropped(bareudp->dev);
88 goto drop;
89 }
90 ipversion >>= 4;
91
92 if (ipversion == 4) {
93 proto = htons(ETH_P_IP);
94 } else if (ipversion == 6 && bareudp->multi_proto_mode) {
95 proto = htons(ETH_P_IPV6);
96 } else {
97 dev_dstats_rx_dropped(bareudp->dev);
98 goto drop;
99 }
100 } else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
101 struct iphdr *tunnel_hdr;
102
103 tunnel_hdr = (struct iphdr *)skb_network_header(skb);
104 if (tunnel_hdr->version == 4) {
105 if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
106 proto = bareudp->ethertype;
107 } else if (bareudp->multi_proto_mode &&
108 ipv4_is_multicast(tunnel_hdr->daddr)) {
109 proto = htons(ETH_P_MPLS_MC);
110 } else {
111 dev_dstats_rx_dropped(bareudp->dev);
112 goto drop;
113 }
114 } else {
115 int addr_type;
116 struct ipv6hdr *tunnel_hdr_v6;
117
118 tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
119 addr_type =
120 ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
121 if (!(addr_type & IPV6_ADDR_MULTICAST)) {
122 proto = bareudp->ethertype;
123 } else if (bareudp->multi_proto_mode &&
124 (addr_type & IPV6_ADDR_MULTICAST)) {
125 proto = htons(ETH_P_MPLS_MC);
126 } else {
127 dev_dstats_rx_dropped(bareudp->dev);
128 goto drop;
129 }
130 }
131 } else {
132 proto = bareudp->ethertype;
133 }
134
135 if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
136 proto,
137 !net_eq(bareudp->net,
138 dev_net(bareudp->dev)))) {
139 dev_dstats_rx_dropped(bareudp->dev);
140 goto drop;
141 }
142
143 __set_bit(IP_TUNNEL_KEY_BIT, key);
144
145 tun_dst = udp_tun_rx_dst(skb, family, key, 0, 0);
146 if (!tun_dst) {
147 dev_dstats_rx_dropped(bareudp->dev);
148 goto drop;
149 }
150 skb_dst_set(skb, &tun_dst->dst);
151 skb->dev = bareudp->dev;
152 skb_reset_mac_header(skb);
153
154 /* Save offset of outer header relative to skb->head,
155 * because we are going to reset the network header to the inner header
156 * and might change skb->head.
157 */
158 nh = skb_network_header(skb) - skb->head;
159
160 skb_reset_network_header(skb);
161
162 if (!pskb_inet_may_pull(skb)) {
163 DEV_STATS_INC(bareudp->dev, rx_length_errors);
164 DEV_STATS_INC(bareudp->dev, rx_errors);
165 goto drop;
166 }
167
168 /* Get the outer header. */
169 oiph = skb->head + nh;
170
171 if (!ipv6_mod_enabled() || family == AF_INET)
172 err = IP_ECN_decapsulate(oiph, skb);
173 else
174 err = IP6_ECN_decapsulate(oiph, skb);
175
176 if (unlikely(err)) {
177 if (log_ecn_error) {
178 if (!ipv6_mod_enabled() || family == AF_INET)
179 net_info_ratelimited("non-ECT from %pI4 "
180 "with TOS=%#x\n",
181 &((struct iphdr *)oiph)->saddr,
182 ((struct iphdr *)oiph)->tos);
183 else
184 net_info_ratelimited("non-ECT from %pI6\n",
185 &((struct ipv6hdr *)oiph)->saddr);
186 }
187 if (err > 1) {
188 DEV_STATS_INC(bareudp->dev, rx_frame_errors);
189 DEV_STATS_INC(bareudp->dev, rx_errors);
190 goto drop;
191 }
192 }
193
194 len = skb->len;
195 err = gro_cells_receive(&bareudp->gro_cells, skb);
196 if (likely(err == NET_RX_SUCCESS))
197 dev_dstats_rx_add(bareudp->dev, len);
198
199 return 0;
200 drop:
201 /* Consume bad packet */
202 kfree_skb(skb);
203
204 return 0;
205 }
206
bareudp_err_lookup(struct sock * sk,struct sk_buff * skb)207 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
208 {
209 return 0;
210 }
211
bareudp_init(struct net_device * dev)212 static int bareudp_init(struct net_device *dev)
213 {
214 struct bareudp_dev *bareudp = netdev_priv(dev);
215 int err;
216
217 err = gro_cells_init(&bareudp->gro_cells, dev);
218 if (err)
219 return err;
220
221 return 0;
222 }
223
bareudp_uninit(struct net_device * dev)224 static void bareudp_uninit(struct net_device *dev)
225 {
226 struct bareudp_dev *bareudp = netdev_priv(dev);
227
228 gro_cells_destroy(&bareudp->gro_cells);
229 }
230
bareudp_create_sock(struct net * net,__be16 port)231 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
232 {
233 struct udp_port_cfg udp_conf;
234 struct socket *sock;
235 int err;
236
237 memset(&udp_conf, 0, sizeof(udp_conf));
238
239 if (ipv6_mod_enabled())
240 udp_conf.family = AF_INET6;
241 else
242 udp_conf.family = AF_INET;
243
244 udp_conf.local_udp_port = port;
245 /* Open UDP socket */
246 err = udp_sock_create(net, &udp_conf, &sock);
247 if (err < 0)
248 return ERR_PTR(err);
249
250 udp_allow_gso(sock->sk);
251 return sock;
252 }
253
254 /* Create new listen socket if needed */
bareudp_socket_create(struct bareudp_dev * bareudp,__be16 port)255 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
256 {
257 struct udp_tunnel_sock_cfg tunnel_cfg;
258 struct socket *sock;
259
260 sock = bareudp_create_sock(bareudp->net, port);
261 if (IS_ERR(sock))
262 return PTR_ERR(sock);
263
264 /* Mark socket as an encapsulation socket */
265 memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
266 tunnel_cfg.sk_user_data = bareudp;
267 tunnel_cfg.encap_type = 1;
268 tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
269 tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
270 tunnel_cfg.encap_destroy = NULL;
271 setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
272
273 rcu_assign_pointer(bareudp->sock, sock);
274 return 0;
275 }
276
bareudp_open(struct net_device * dev)277 static int bareudp_open(struct net_device *dev)
278 {
279 struct bareudp_dev *bareudp = netdev_priv(dev);
280 int ret = 0;
281
282 ret = bareudp_socket_create(bareudp, bareudp->port);
283 return ret;
284 }
285
bareudp_sock_release(struct bareudp_dev * bareudp)286 static void bareudp_sock_release(struct bareudp_dev *bareudp)
287 {
288 struct socket *sock;
289
290 sock = bareudp->sock;
291 rcu_assign_pointer(bareudp->sock, NULL);
292 synchronize_net();
293 udp_tunnel_sock_release(sock);
294 }
295
bareudp_stop(struct net_device * dev)296 static int bareudp_stop(struct net_device *dev)
297 {
298 struct bareudp_dev *bareudp = netdev_priv(dev);
299
300 bareudp_sock_release(bareudp);
301 return 0;
302 }
303
bareudp_xmit_skb(struct sk_buff * skb,struct net_device * dev,struct bareudp_dev * bareudp,const struct ip_tunnel_info * info)304 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
305 struct bareudp_dev *bareudp,
306 const struct ip_tunnel_info *info)
307 {
308 bool udp_sum = test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
309 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
310 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
311 struct socket *sock = rcu_dereference(bareudp->sock);
312 const struct ip_tunnel_key *key = &info->key;
313 struct rtable *rt;
314 __be16 sport, df;
315 int min_headroom;
316 __u8 tos, ttl;
317 __be32 saddr;
318 int err;
319
320 if (skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
321 return -EINVAL;
322
323 if (!sock)
324 return -ESHUTDOWN;
325
326 sport = udp_flow_src_port(bareudp->net, skb,
327 bareudp->sport_min, USHRT_MAX,
328 true);
329 rt = udp_tunnel_dst_lookup(skb, dev, bareudp->net, 0, &saddr, &info->key,
330 sport, bareudp->port, key->tos,
331 use_cache ?
332 (struct dst_cache *)&info->dst_cache : NULL);
333
334 if (IS_ERR(rt))
335 return PTR_ERR(rt);
336
337 skb_tunnel_check_pmtu(skb, &rt->dst,
338 BAREUDP_IPV4_HLEN + info->options_len, false);
339
340 tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
341 ttl = key->ttl;
342 df = test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags) ?
343 htons(IP_DF) : 0;
344 skb_scrub_packet(skb, xnet);
345
346 err = -ENOSPC;
347 if (!skb_pull(skb, skb_network_offset(skb)))
348 goto free_dst;
349
350 min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
351 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
352
353 err = skb_cow_head(skb, min_headroom);
354 if (unlikely(err))
355 goto free_dst;
356
357 err = udp_tunnel_handle_offloads(skb, udp_sum);
358 if (err)
359 goto free_dst;
360
361 skb_set_inner_protocol(skb, bareudp->ethertype);
362 udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
363 tos, ttl, df, sport, bareudp->port,
364 !net_eq(bareudp->net, dev_net(bareudp->dev)),
365 !test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags),
366 0);
367 return 0;
368
369 free_dst:
370 dst_release(&rt->dst);
371 return err;
372 }
373
bareudp6_xmit_skb(struct sk_buff * skb,struct net_device * dev,struct bareudp_dev * bareudp,const struct ip_tunnel_info * info)374 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
375 struct bareudp_dev *bareudp,
376 const struct ip_tunnel_info *info)
377 {
378 bool udp_sum = test_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
379 bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
380 bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
381 struct socket *sock = rcu_dereference(bareudp->sock);
382 const struct ip_tunnel_key *key = &info->key;
383 struct dst_entry *dst = NULL;
384 struct in6_addr saddr, daddr;
385 int min_headroom;
386 __u8 prio, ttl;
387 __be16 sport;
388 int err;
389
390 if (skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB)))
391 return -EINVAL;
392
393 if (!sock)
394 return -ESHUTDOWN;
395
396 sport = udp_flow_src_port(bareudp->net, skb,
397 bareudp->sport_min, USHRT_MAX,
398 true);
399 dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock, 0, &saddr,
400 key, sport, bareudp->port, key->tos,
401 use_cache ?
402 (struct dst_cache *) &info->dst_cache : NULL);
403 if (IS_ERR(dst))
404 return PTR_ERR(dst);
405
406 skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
407 false);
408
409 prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
410 ttl = key->ttl;
411
412 skb_scrub_packet(skb, xnet);
413
414 err = -ENOSPC;
415 if (!skb_pull(skb, skb_network_offset(skb)))
416 goto free_dst;
417
418 min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
419 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
420
421 err = skb_cow_head(skb, min_headroom);
422 if (unlikely(err))
423 goto free_dst;
424
425 err = udp_tunnel_handle_offloads(skb, udp_sum);
426 if (err)
427 goto free_dst;
428
429 daddr = info->key.u.ipv6.dst;
430 udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
431 &saddr, &daddr, prio, ttl,
432 info->key.label, sport, bareudp->port,
433 !test_bit(IP_TUNNEL_CSUM_BIT,
434 info->key.tun_flags),
435 0);
436 return 0;
437
438 free_dst:
439 dst_release(dst);
440 return err;
441 }
442
bareudp_proto_valid(struct bareudp_dev * bareudp,__be16 proto)443 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
444 {
445 if (bareudp->ethertype == proto)
446 return true;
447
448 if (!bareudp->multi_proto_mode)
449 return false;
450
451 if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
452 proto == htons(ETH_P_MPLS_MC))
453 return true;
454
455 if (bareudp->ethertype == htons(ETH_P_IP) &&
456 proto == htons(ETH_P_IPV6))
457 return true;
458
459 return false;
460 }
461
bareudp_xmit(struct sk_buff * skb,struct net_device * dev)462 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
463 {
464 struct bareudp_dev *bareudp = netdev_priv(dev);
465 struct ip_tunnel_info *info = NULL;
466 int err;
467
468 if (!bareudp_proto_valid(bareudp, skb->protocol)) {
469 err = -EINVAL;
470 goto tx_error;
471 }
472
473 info = skb_tunnel_info(skb);
474 if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
475 err = -EINVAL;
476 goto tx_error;
477 }
478
479 rcu_read_lock();
480 if (ipv6_mod_enabled() && info->mode & IP_TUNNEL_INFO_IPV6)
481 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
482 else
483 err = bareudp_xmit_skb(skb, dev, bareudp, info);
484
485 rcu_read_unlock();
486
487 if (likely(!err))
488 return NETDEV_TX_OK;
489 tx_error:
490 dev_kfree_skb(skb);
491
492 if (err == -ELOOP)
493 DEV_STATS_INC(dev, collisions);
494 else if (err == -ENETUNREACH)
495 DEV_STATS_INC(dev, tx_carrier_errors);
496
497 DEV_STATS_INC(dev, tx_errors);
498 return NETDEV_TX_OK;
499 }
500
bareudp_fill_metadata_dst(struct net_device * dev,struct sk_buff * skb)501 static int bareudp_fill_metadata_dst(struct net_device *dev,
502 struct sk_buff *skb)
503 {
504 struct ip_tunnel_info *info = skb_tunnel_info(skb);
505 struct bareudp_dev *bareudp = netdev_priv(dev);
506 bool use_cache;
507 __be16 sport;
508
509 use_cache = ip_tunnel_dst_cache_usable(skb, info);
510 sport = udp_flow_src_port(bareudp->net, skb,
511 bareudp->sport_min, USHRT_MAX,
512 true);
513
514 if (!ipv6_mod_enabled() || ip_tunnel_info_af(info) == AF_INET) {
515 struct rtable *rt;
516 __be32 saddr;
517
518 rt = udp_tunnel_dst_lookup(skb, dev, bareudp->net, 0, &saddr,
519 &info->key, sport, bareudp->port,
520 info->key.tos,
521 use_cache ? &info->dst_cache : NULL);
522 if (IS_ERR(rt))
523 return PTR_ERR(rt);
524
525 ip_rt_put(rt);
526 info->key.u.ipv4.src = saddr;
527 } else if (ip_tunnel_info_af(info) == AF_INET6) {
528 struct dst_entry *dst;
529 struct in6_addr saddr;
530 struct socket *sock = rcu_dereference(bareudp->sock);
531
532 dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock,
533 0, &saddr, &info->key,
534 sport, bareudp->port, info->key.tos,
535 use_cache ? &info->dst_cache : NULL);
536 if (IS_ERR(dst))
537 return PTR_ERR(dst);
538
539 dst_release(dst);
540 info->key.u.ipv6.src = saddr;
541 } else {
542 return -EINVAL;
543 }
544
545 info->key.tp_src = sport;
546 info->key.tp_dst = bareudp->port;
547 return 0;
548 }
549
550 static const struct net_device_ops bareudp_netdev_ops = {
551 .ndo_init = bareudp_init,
552 .ndo_uninit = bareudp_uninit,
553 .ndo_open = bareudp_open,
554 .ndo_stop = bareudp_stop,
555 .ndo_start_xmit = bareudp_xmit,
556 .ndo_fill_metadata_dst = bareudp_fill_metadata_dst,
557 };
558
559 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
560 [IFLA_BAREUDP_PORT] = { .type = NLA_U16 },
561 [IFLA_BAREUDP_ETHERTYPE] = { .type = NLA_U16 },
562 [IFLA_BAREUDP_SRCPORT_MIN] = { .type = NLA_U16 },
563 [IFLA_BAREUDP_MULTIPROTO_MODE] = { .type = NLA_FLAG },
564 };
565
566 /* Info for udev, that this is a virtual tunnel endpoint */
567 static const struct device_type bareudp_type = {
568 .name = "bareudp",
569 };
570
571 /* Initialize the device structure. */
bareudp_setup(struct net_device * dev)572 static void bareudp_setup(struct net_device *dev)
573 {
574 dev->netdev_ops = &bareudp_netdev_ops;
575 dev->needs_free_netdev = true;
576 SET_NETDEV_DEVTYPE(dev, &bareudp_type);
577 dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
578 dev->features |= NETIF_F_RXCSUM;
579 dev->features |= NETIF_F_GSO_SOFTWARE;
580 dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
581 dev->hw_features |= NETIF_F_RXCSUM;
582 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
583 dev->hard_header_len = 0;
584 dev->addr_len = 0;
585 dev->mtu = ETH_DATA_LEN;
586 dev->min_mtu = IPV4_MIN_MTU;
587 dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
588 dev->type = ARPHRD_NONE;
589 netif_keep_dst(dev);
590 dev->priv_flags |= IFF_NO_QUEUE;
591 dev->lltx = true;
592 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
593 dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
594 }
595
bareudp_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)596 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
597 struct netlink_ext_ack *extack)
598 {
599 if (!data) {
600 NL_SET_ERR_MSG(extack,
601 "Not enough attributes provided to perform the operation");
602 return -EINVAL;
603 }
604 return 0;
605 }
606
bareudp2info(struct nlattr * data[],struct bareudp_conf * conf,struct netlink_ext_ack * extack)607 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
608 struct netlink_ext_ack *extack)
609 {
610 memset(conf, 0, sizeof(*conf));
611
612 if (!data[IFLA_BAREUDP_PORT]) {
613 NL_SET_ERR_MSG(extack, "port not specified");
614 return -EINVAL;
615 }
616 if (!data[IFLA_BAREUDP_ETHERTYPE]) {
617 NL_SET_ERR_MSG(extack, "ethertype not specified");
618 return -EINVAL;
619 }
620
621 conf->port = nla_get_u16(data[IFLA_BAREUDP_PORT]);
622 conf->ethertype = nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
623
624 if (data[IFLA_BAREUDP_SRCPORT_MIN])
625 conf->sport_min = nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
626
627 if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
628 conf->multi_proto_mode = true;
629
630 return 0;
631 }
632
bareudp_find_dev(struct bareudp_net * bn,const struct bareudp_conf * conf)633 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
634 const struct bareudp_conf *conf)
635 {
636 struct bareudp_dev *bareudp, *t = NULL;
637
638 list_for_each_entry(bareudp, &bn->bareudp_list, next) {
639 if (conf->port == bareudp->port)
640 t = bareudp;
641 }
642 return t;
643 }
644
bareudp_configure(struct net * net,struct net_device * dev,struct bareudp_conf * conf,struct netlink_ext_ack * extack)645 static int bareudp_configure(struct net *net, struct net_device *dev,
646 struct bareudp_conf *conf,
647 struct netlink_ext_ack *extack)
648 {
649 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
650 struct bareudp_dev *t, *bareudp = netdev_priv(dev);
651 int err;
652
653 bareudp->net = net;
654 bareudp->dev = dev;
655 t = bareudp_find_dev(bn, conf);
656 if (t) {
657 NL_SET_ERR_MSG(extack, "Another bareudp device using the same port already exists");
658 return -EBUSY;
659 }
660
661 if (conf->multi_proto_mode &&
662 (conf->ethertype != htons(ETH_P_MPLS_UC) &&
663 conf->ethertype != htons(ETH_P_IP))) {
664 NL_SET_ERR_MSG(extack, "Cannot set multiproto mode for this ethertype (only IPv4 and unicast MPLS are supported)");
665 return -EINVAL;
666 }
667
668 bareudp->port = conf->port;
669 bareudp->ethertype = conf->ethertype;
670 bareudp->sport_min = conf->sport_min;
671 bareudp->multi_proto_mode = conf->multi_proto_mode;
672
673 err = register_netdevice(dev);
674 if (err)
675 return err;
676
677 list_add(&bareudp->next, &bn->bareudp_list);
678 return 0;
679 }
680
bareudp_link_config(struct net_device * dev,struct nlattr * tb[])681 static int bareudp_link_config(struct net_device *dev,
682 struct nlattr *tb[])
683 {
684 int err;
685
686 if (tb[IFLA_MTU]) {
687 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
688 if (err)
689 return err;
690 }
691 return 0;
692 }
693
bareudp_dellink(struct net_device * dev,struct list_head * head)694 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
695 {
696 struct bareudp_dev *bareudp = netdev_priv(dev);
697
698 list_del(&bareudp->next);
699 unregister_netdevice_queue(dev, head);
700 }
701
bareudp_newlink(struct net_device * dev,struct rtnl_newlink_params * params,struct netlink_ext_ack * extack)702 static int bareudp_newlink(struct net_device *dev,
703 struct rtnl_newlink_params *params,
704 struct netlink_ext_ack *extack)
705 {
706 struct net *link_net = rtnl_newlink_link_net(params);
707 struct nlattr **data = params->data;
708 struct nlattr **tb = params->tb;
709 struct bareudp_conf conf;
710 int err;
711
712 err = bareudp2info(data, &conf, extack);
713 if (err)
714 return err;
715
716 err = bareudp_configure(link_net, dev, &conf, extack);
717 if (err)
718 return err;
719
720 err = bareudp_link_config(dev, tb);
721 if (err)
722 goto err_unconfig;
723
724 return 0;
725
726 err_unconfig:
727 bareudp_dellink(dev, NULL);
728 return err;
729 }
730
bareudp_get_size(const struct net_device * dev)731 static size_t bareudp_get_size(const struct net_device *dev)
732 {
733 return nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_PORT */
734 nla_total_size(sizeof(__be16)) + /* IFLA_BAREUDP_ETHERTYPE */
735 nla_total_size(sizeof(__u16)) + /* IFLA_BAREUDP_SRCPORT_MIN */
736 nla_total_size(0) + /* IFLA_BAREUDP_MULTIPROTO_MODE */
737 0;
738 }
739
bareudp_fill_info(struct sk_buff * skb,const struct net_device * dev)740 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
741 {
742 struct bareudp_dev *bareudp = netdev_priv(dev);
743
744 if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
745 goto nla_put_failure;
746 if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
747 goto nla_put_failure;
748 if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
749 goto nla_put_failure;
750 if (bareudp->multi_proto_mode &&
751 nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
752 goto nla_put_failure;
753
754 return 0;
755
756 nla_put_failure:
757 return -EMSGSIZE;
758 }
759
760 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
761 .kind = "bareudp",
762 .maxtype = IFLA_BAREUDP_MAX,
763 .policy = bareudp_policy,
764 .priv_size = sizeof(struct bareudp_dev),
765 .setup = bareudp_setup,
766 .validate = bareudp_validate,
767 .newlink = bareudp_newlink,
768 .dellink = bareudp_dellink,
769 .get_size = bareudp_get_size,
770 .fill_info = bareudp_fill_info,
771 };
772
bareudp_init_net(struct net * net)773 static __net_init int bareudp_init_net(struct net *net)
774 {
775 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
776
777 INIT_LIST_HEAD(&bn->bareudp_list);
778 return 0;
779 }
780
bareudp_exit_rtnl_net(struct net * net,struct list_head * dev_kill_list)781 static void __net_exit bareudp_exit_rtnl_net(struct net *net,
782 struct list_head *dev_kill_list)
783 {
784 struct bareudp_net *bn = net_generic(net, bareudp_net_id);
785 struct bareudp_dev *bareudp, *next;
786
787 list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
788 bareudp_dellink(bareudp->dev, dev_kill_list);
789 }
790
791 static struct pernet_operations bareudp_net_ops = {
792 .init = bareudp_init_net,
793 .exit_rtnl = bareudp_exit_rtnl_net,
794 .id = &bareudp_net_id,
795 .size = sizeof(struct bareudp_net),
796 };
797
bareudp_init_module(void)798 static int __init bareudp_init_module(void)
799 {
800 int rc;
801
802 rc = register_pernet_subsys(&bareudp_net_ops);
803 if (rc)
804 goto out1;
805
806 rc = rtnl_link_register(&bareudp_link_ops);
807 if (rc)
808 goto out2;
809
810 return 0;
811 out2:
812 unregister_pernet_subsys(&bareudp_net_ops);
813 out1:
814 return rc;
815 }
816 late_initcall(bareudp_init_module);
817
bareudp_cleanup_module(void)818 static void __exit bareudp_cleanup_module(void)
819 {
820 rtnl_link_unregister(&bareudp_link_ops);
821 unregister_pernet_subsys(&bareudp_net_ops);
822 }
823 module_exit(bareudp_cleanup_module);
824
825 MODULE_ALIAS_RTNL_LINK("bareudp");
826 MODULE_LICENSE("GPL");
827 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
828 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");
829