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
29static bool log_ecn_error = true;
30module_param(log_ecn_error, bool, 0644);
31MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
32
33/* per-network namespace private data for this module */
34
35static unsigned int bareudp_net_id;
36
37struct bareudp_net {
38 struct list_head bareudp_list;
39};
40
41struct bareudp_conf {
42 __be16 ethertype;
43 __be16 port;
44 u16 sport_min;
45 bool multi_proto_mode;
46};
47
48/* Pseudo network device */
49struct 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
61static 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, to: &ipversion,
86 len: sizeof(ipversion))) {
87 dev_dstats_rx_dropped(dev: 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(dev: 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(addr: tunnel_hdr->daddr)) {
106 proto = bareudp->ethertype;
107 } else if (bareudp->multi_proto_mode &&
108 ipv4_is_multicast(addr: tunnel_hdr->daddr)) {
109 proto = htons(ETH_P_MPLS_MC);
110 } else {
111 dev_dstats_rx_dropped(dev: 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(addr: (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(dev: 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 inner_proto: proto,
137 xnet: !net_eq(net1: bareudp->net,
138 net2: dev_net(dev: bareudp->dev)))) {
139 dev_dstats_rx_dropped(dev: 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, flags: key, tunnel_id: 0, md_size: 0);
146 if (!tun_dst) {
147 dev_dstats_rx_dropped(dev: bareudp->dev);
148 goto drop;
149 }
150 skb_dst_set(skb, dst: &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(oipv6h: 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(gcells: &bareudp->gro_cells, skb);
196 if (likely(err == NET_RX_SUCCESS))
197 dev_dstats_rx_add(dev: bareudp->dev, len);
198
199 return 0;
200drop:
201 /* Consume bad packet */
202 kfree_skb(skb);
203
204 return 0;
205}
206
207static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
208{
209 return 0;
210}
211
212static 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(gcells: &bareudp->gro_cells, dev);
218 if (err)
219 return err;
220
221 return 0;
222}
223
224static void bareudp_uninit(struct net_device *dev)
225{
226 struct bareudp_dev *bareudp = netdev_priv(dev);
227
228 gro_cells_destroy(gcells: &bareudp->gro_cells);
229}
230
231static 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, cfg: &udp_conf, sockp: &sock);
247 if (err < 0)
248 return ERR_PTR(error: err);
249
250 udp_allow_gso(sk: sock->sk);
251 return sock;
252}
253
254/* Create new listen socket if needed */
255static 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(net: bareudp->net, port);
261 if (IS_ERR(ptr: sock))
262 return PTR_ERR(ptr: 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(net: bareudp->net, sock, sock_cfg: &tunnel_cfg);
272
273 rcu_assign_pointer(bareudp->sock, sock);
274 return 0;
275}
276
277static 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, port: bareudp->port);
283 return ret;
284}
285
286static 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
296static 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
304static 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(net1: bareudp->net, net2: dev_net(dev: 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, inner_proto_inherit: skb->protocol != htons(ETH_P_TEB)))
321 return -EINVAL;
322
323 if (!sock)
324 return -ESHUTDOWN;
325
326 sport = udp_flow_src_port(net: bareudp->net, skb,
327 min: bareudp->sport_min, USHRT_MAX,
328 use_eth: true);
329 rt = udp_tunnel_dst_lookup(skb, dev, net: bareudp->net, oif: 0, saddr: &saddr, key: &info->key,
330 sport, dport: bareudp->port, tos: key->tos,
331 dst_cache: use_cache ?
332 (struct dst_cache *)&info->dst_cache : NULL);
333
334 if (IS_ERR(ptr: rt))
335 return PTR_ERR(ptr: rt);
336
337 skb_tunnel_check_pmtu(skb, encap_dst: &rt->dst,
338 BAREUDP_IPV4_HLEN + info->options_len, reply: false);
339
340 tos = ip_tunnel_ecn_encap(tos: key->tos, iph: 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, len: 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, headroom: min_headroom);
354 if (unlikely(err))
355 goto free_dst;
356
357 err = udp_tunnel_handle_offloads(skb, udp_csum: udp_sum);
358 if (err)
359 goto free_dst;
360
361 skb_set_inner_protocol(skb, protocol: bareudp->ethertype);
362 udp_tunnel_xmit_skb(rt, sk: sock->sk, skb, src: saddr, dst: info->key.u.ipv4.dst,
363 tos, ttl, df, src_port: sport, dst_port: bareudp->port,
364 xnet: !net_eq(net1: bareudp->net, net2: dev_net(dev: bareudp->dev)),
365 nocheck: !test_bit(IP_TUNNEL_CSUM_BIT,
366 info->key.tun_flags));
367 return 0;
368
369free_dst:
370 dst_release(dst: &rt->dst);
371 return err;
372}
373
374static 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(net1: bareudp->net, net2: dev_net(dev: 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, inner_proto_inherit: skb->protocol != htons(ETH_P_TEB)))
391 return -EINVAL;
392
393 if (!sock)
394 return -ESHUTDOWN;
395
396 sport = udp_flow_src_port(net: bareudp->net, skb,
397 min: bareudp->sport_min, USHRT_MAX,
398 use_eth: true);
399 dst = udp_tunnel6_dst_lookup(skb, dev, net: bareudp->net, sock, oif: 0, saddr: &saddr,
400 key, sport, dport: bareudp->port, dsfield: key->tos,
401 dst_cache: use_cache ?
402 (struct dst_cache *) &info->dst_cache : NULL);
403 if (IS_ERR(ptr: dst))
404 return PTR_ERR(ptr: dst);
405
406 skb_tunnel_check_pmtu(skb, encap_dst: dst, BAREUDP_IPV6_HLEN + info->options_len,
407 reply: false);
408
409 prio = ip_tunnel_ecn_encap(tos: key->tos, iph: ip_hdr(skb), skb);
410 ttl = key->ttl;
411
412 skb_scrub_packet(skb, xnet);
413
414 err = -ENOSPC;
415 if (!skb_pull(skb, len: 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, headroom: min_headroom);
422 if (unlikely(err))
423 goto free_dst;
424
425 err = udp_tunnel_handle_offloads(skb, udp_csum: udp_sum);
426 if (err)
427 goto free_dst;
428
429 daddr = info->key.u.ipv6.dst;
430 udp_tunnel6_xmit_skb(dst, sk: sock->sk, skb, dev,
431 saddr: &saddr, daddr: &daddr, prio, ttl,
432 label: info->key.label, src_port: sport, dst_port: bareudp->port,
433 nocheck: !test_bit(IP_TUNNEL_CSUM_BIT,
434 info->key.tun_flags));
435 return 0;
436
437free_dst:
438 dst_release(dst);
439 return err;
440}
441
442static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
443{
444 if (bareudp->ethertype == proto)
445 return true;
446
447 if (!bareudp->multi_proto_mode)
448 return false;
449
450 if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
451 proto == htons(ETH_P_MPLS_MC))
452 return true;
453
454 if (bareudp->ethertype == htons(ETH_P_IP) &&
455 proto == htons(ETH_P_IPV6))
456 return true;
457
458 return false;
459}
460
461static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
462{
463 struct bareudp_dev *bareudp = netdev_priv(dev);
464 struct ip_tunnel_info *info = NULL;
465 int err;
466
467 if (!bareudp_proto_valid(bareudp, proto: skb->protocol)) {
468 err = -EINVAL;
469 goto tx_error;
470 }
471
472 info = skb_tunnel_info(skb);
473 if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
474 err = -EINVAL;
475 goto tx_error;
476 }
477
478 rcu_read_lock();
479 if (ipv6_mod_enabled() && info->mode & IP_TUNNEL_INFO_IPV6)
480 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
481 else
482 err = bareudp_xmit_skb(skb, dev, bareudp, info);
483
484 rcu_read_unlock();
485
486 if (likely(!err))
487 return NETDEV_TX_OK;
488tx_error:
489 dev_kfree_skb(skb);
490
491 if (err == -ELOOP)
492 DEV_STATS_INC(dev, collisions);
493 else if (err == -ENETUNREACH)
494 DEV_STATS_INC(dev, tx_carrier_errors);
495
496 DEV_STATS_INC(dev, tx_errors);
497 return NETDEV_TX_OK;
498}
499
500static int bareudp_fill_metadata_dst(struct net_device *dev,
501 struct sk_buff *skb)
502{
503 struct ip_tunnel_info *info = skb_tunnel_info(skb);
504 struct bareudp_dev *bareudp = netdev_priv(dev);
505 bool use_cache;
506 __be16 sport;
507
508 use_cache = ip_tunnel_dst_cache_usable(skb, info);
509 sport = udp_flow_src_port(net: bareudp->net, skb,
510 min: bareudp->sport_min, USHRT_MAX,
511 use_eth: true);
512
513 if (!ipv6_mod_enabled() || ip_tunnel_info_af(tun_info: info) == AF_INET) {
514 struct rtable *rt;
515 __be32 saddr;
516
517 rt = udp_tunnel_dst_lookup(skb, dev, net: bareudp->net, oif: 0, saddr: &saddr,
518 key: &info->key, sport, dport: bareudp->port,
519 tos: info->key.tos,
520 dst_cache: use_cache ? &info->dst_cache : NULL);
521 if (IS_ERR(ptr: rt))
522 return PTR_ERR(ptr: rt);
523
524 ip_rt_put(rt);
525 info->key.u.ipv4.src = saddr;
526 } else if (ip_tunnel_info_af(tun_info: info) == AF_INET6) {
527 struct dst_entry *dst;
528 struct in6_addr saddr;
529 struct socket *sock = rcu_dereference(bareudp->sock);
530
531 dst = udp_tunnel6_dst_lookup(skb, dev, net: bareudp->net, sock,
532 oif: 0, saddr: &saddr, key: &info->key,
533 sport, dport: bareudp->port, dsfield: info->key.tos,
534 dst_cache: use_cache ? &info->dst_cache : NULL);
535 if (IS_ERR(ptr: dst))
536 return PTR_ERR(ptr: dst);
537
538 dst_release(dst);
539 info->key.u.ipv6.src = saddr;
540 } else {
541 return -EINVAL;
542 }
543
544 info->key.tp_src = sport;
545 info->key.tp_dst = bareudp->port;
546 return 0;
547}
548
549static const struct net_device_ops bareudp_netdev_ops = {
550 .ndo_init = bareudp_init,
551 .ndo_uninit = bareudp_uninit,
552 .ndo_open = bareudp_open,
553 .ndo_stop = bareudp_stop,
554 .ndo_start_xmit = bareudp_xmit,
555 .ndo_fill_metadata_dst = bareudp_fill_metadata_dst,
556};
557
558static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
559 [IFLA_BAREUDP_PORT] = { .type = NLA_U16 },
560 [IFLA_BAREUDP_ETHERTYPE] = { .type = NLA_U16 },
561 [IFLA_BAREUDP_SRCPORT_MIN] = { .type = NLA_U16 },
562 [IFLA_BAREUDP_MULTIPROTO_MODE] = { .type = NLA_FLAG },
563};
564
565/* Info for udev, that this is a virtual tunnel endpoint */
566static const struct device_type bareudp_type = {
567 .name = "bareudp",
568};
569
570/* Initialize the device structure. */
571static void bareudp_setup(struct net_device *dev)
572{
573 dev->netdev_ops = &bareudp_netdev_ops;
574 dev->needs_free_netdev = true;
575 SET_NETDEV_DEVTYPE(dev, &bareudp_type);
576 dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
577 dev->features |= NETIF_F_RXCSUM;
578 dev->features |= NETIF_F_GSO_SOFTWARE;
579 dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
580 dev->hw_features |= NETIF_F_RXCSUM;
581 dev->hw_features |= NETIF_F_GSO_SOFTWARE;
582 dev->hard_header_len = 0;
583 dev->addr_len = 0;
584 dev->mtu = ETH_DATA_LEN;
585 dev->min_mtu = IPV4_MIN_MTU;
586 dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
587 dev->type = ARPHRD_NONE;
588 netif_keep_dst(dev);
589 dev->priv_flags |= IFF_NO_QUEUE;
590 dev->lltx = true;
591 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
592 dev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS;
593}
594
595static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
596 struct netlink_ext_ack *extack)
597{
598 if (!data) {
599 NL_SET_ERR_MSG(extack,
600 "Not enough attributes provided to perform the operation");
601 return -EINVAL;
602 }
603 return 0;
604}
605
606static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
607 struct netlink_ext_ack *extack)
608{
609 memset(conf, 0, sizeof(*conf));
610
611 if (!data[IFLA_BAREUDP_PORT]) {
612 NL_SET_ERR_MSG(extack, "port not specified");
613 return -EINVAL;
614 }
615 if (!data[IFLA_BAREUDP_ETHERTYPE]) {
616 NL_SET_ERR_MSG(extack, "ethertype not specified");
617 return -EINVAL;
618 }
619
620 conf->port = nla_get_u16(nla: data[IFLA_BAREUDP_PORT]);
621 conf->ethertype = nla_get_u16(nla: data[IFLA_BAREUDP_ETHERTYPE]);
622
623 if (data[IFLA_BAREUDP_SRCPORT_MIN])
624 conf->sport_min = nla_get_u16(nla: data[IFLA_BAREUDP_SRCPORT_MIN]);
625
626 if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
627 conf->multi_proto_mode = true;
628
629 return 0;
630}
631
632static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
633 const struct bareudp_conf *conf)
634{
635 struct bareudp_dev *bareudp, *t = NULL;
636
637 list_for_each_entry(bareudp, &bn->bareudp_list, next) {
638 if (conf->port == bareudp->port)
639 t = bareudp;
640 }
641 return t;
642}
643
644static int bareudp_configure(struct net *net, struct net_device *dev,
645 struct bareudp_conf *conf,
646 struct netlink_ext_ack *extack)
647{
648 struct bareudp_net *bn = net_generic(net, id: bareudp_net_id);
649 struct bareudp_dev *t, *bareudp = netdev_priv(dev);
650 int err;
651
652 bareudp->net = net;
653 bareudp->dev = dev;
654 t = bareudp_find_dev(bn, conf);
655 if (t) {
656 NL_SET_ERR_MSG(extack, "Another bareudp device using the same port already exists");
657 return -EBUSY;
658 }
659
660 if (conf->multi_proto_mode &&
661 (conf->ethertype != htons(ETH_P_MPLS_UC) &&
662 conf->ethertype != htons(ETH_P_IP))) {
663 NL_SET_ERR_MSG(extack, "Cannot set multiproto mode for this ethertype (only IPv4 and unicast MPLS are supported)");
664 return -EINVAL;
665 }
666
667 bareudp->port = conf->port;
668 bareudp->ethertype = conf->ethertype;
669 bareudp->sport_min = conf->sport_min;
670 bareudp->multi_proto_mode = conf->multi_proto_mode;
671
672 err = register_netdevice(dev);
673 if (err)
674 return err;
675
676 list_add(new: &bareudp->next, head: &bn->bareudp_list);
677 return 0;
678}
679
680static int bareudp_link_config(struct net_device *dev,
681 struct nlattr *tb[])
682{
683 int err;
684
685 if (tb[IFLA_MTU]) {
686 err = dev_set_mtu(dev, nla_get_u32(nla: tb[IFLA_MTU]));
687 if (err)
688 return err;
689 }
690 return 0;
691}
692
693static void bareudp_dellink(struct net_device *dev, struct list_head *head)
694{
695 struct bareudp_dev *bareudp = netdev_priv(dev);
696
697 list_del(entry: &bareudp->next);
698 unregister_netdevice_queue(dev, head);
699}
700
701static int bareudp_newlink(struct net_device *dev,
702 struct rtnl_newlink_params *params,
703 struct netlink_ext_ack *extack)
704{
705 struct net *link_net = rtnl_newlink_link_net(p: params);
706 struct nlattr **data = params->data;
707 struct nlattr **tb = params->tb;
708 struct bareudp_conf conf;
709 int err;
710
711 err = bareudp2info(data, conf: &conf, extack);
712 if (err)
713 return err;
714
715 err = bareudp_configure(net: link_net, dev, conf: &conf, extack);
716 if (err)
717 return err;
718
719 err = bareudp_link_config(dev, tb);
720 if (err)
721 goto err_unconfig;
722
723 return 0;
724
725err_unconfig:
726 bareudp_dellink(dev, NULL);
727 return err;
728}
729
730static size_t bareudp_get_size(const struct net_device *dev)
731{
732 return nla_total_size(payload: sizeof(__be16)) + /* IFLA_BAREUDP_PORT */
733 nla_total_size(payload: sizeof(__be16)) + /* IFLA_BAREUDP_ETHERTYPE */
734 nla_total_size(payload: sizeof(__u16)) + /* IFLA_BAREUDP_SRCPORT_MIN */
735 nla_total_size(payload: 0) + /* IFLA_BAREUDP_MULTIPROTO_MODE */
736 0;
737}
738
739static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
740{
741 struct bareudp_dev *bareudp = netdev_priv(dev);
742
743 if (nla_put_be16(skb, attrtype: IFLA_BAREUDP_PORT, value: bareudp->port))
744 goto nla_put_failure;
745 if (nla_put_be16(skb, attrtype: IFLA_BAREUDP_ETHERTYPE, value: bareudp->ethertype))
746 goto nla_put_failure;
747 if (nla_put_u16(skb, attrtype: IFLA_BAREUDP_SRCPORT_MIN, value: bareudp->sport_min))
748 goto nla_put_failure;
749 if (bareudp->multi_proto_mode &&
750 nla_put_flag(skb, attrtype: IFLA_BAREUDP_MULTIPROTO_MODE))
751 goto nla_put_failure;
752
753 return 0;
754
755nla_put_failure:
756 return -EMSGSIZE;
757}
758
759static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
760 .kind = "bareudp",
761 .maxtype = IFLA_BAREUDP_MAX,
762 .policy = bareudp_policy,
763 .priv_size = sizeof(struct bareudp_dev),
764 .setup = bareudp_setup,
765 .validate = bareudp_validate,
766 .newlink = bareudp_newlink,
767 .dellink = bareudp_dellink,
768 .get_size = bareudp_get_size,
769 .fill_info = bareudp_fill_info,
770};
771
772static __net_init int bareudp_init_net(struct net *net)
773{
774 struct bareudp_net *bn = net_generic(net, id: bareudp_net_id);
775
776 INIT_LIST_HEAD(list: &bn->bareudp_list);
777 return 0;
778}
779
780static void __net_exit bareudp_exit_rtnl_net(struct net *net,
781 struct list_head *dev_kill_list)
782{
783 struct bareudp_net *bn = net_generic(net, id: bareudp_net_id);
784 struct bareudp_dev *bareudp, *next;
785
786 list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
787 bareudp_dellink(dev: bareudp->dev, head: dev_kill_list);
788}
789
790static struct pernet_operations bareudp_net_ops = {
791 .init = bareudp_init_net,
792 .exit_rtnl = bareudp_exit_rtnl_net,
793 .id = &bareudp_net_id,
794 .size = sizeof(struct bareudp_net),
795};
796
797static 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(ops: &bareudp_link_ops);
806 if (rc)
807 goto out2;
808
809 return 0;
810out2:
811 unregister_pernet_subsys(&bareudp_net_ops);
812out1:
813 return rc;
814}
815late_initcall(bareudp_init_module);
816
817static void __exit bareudp_cleanup_module(void)
818{
819 rtnl_link_unregister(ops: &bareudp_link_ops);
820 unregister_pernet_subsys(&bareudp_net_ops);
821}
822module_exit(bareudp_cleanup_module);
823
824MODULE_ALIAS_RTNL_LINK("bareudp");
825MODULE_LICENSE("GPL");
826MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
827MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");
828

source code of linux/drivers/net/bareudp.c