xref: /linux/drivers/net/bareudp.c (revision 93a3545d812ae7cfe4426374e00a7d8f64ac02e0)
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 /* Pseudo network device */
42 struct bareudp_dev {
43 	struct net         *net;        /* netns for packet i/o */
44 	struct net_device  *dev;        /* netdev for bareudp tunnel */
45 	__be16		   ethertype;
46 	__be16             port;
47 	u16	           sport_min;
48 	bool               multi_proto_mode;
49 	bool               rx_collect_metadata;
50 	struct socket      __rcu *sock;
51 	struct list_head   next;        /* bareudp node  on namespace list */
52 	struct gro_cells   gro_cells;
53 };
54 
55 static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
56 {
57 	struct metadata_dst *tun_dst = NULL;
58 	struct pcpu_sw_netstats *stats;
59 	struct bareudp_dev *bareudp;
60 	unsigned short family;
61 	unsigned int len;
62 	__be16 proto;
63 	void *oiph;
64 	int err;
65 
66 	bareudp = rcu_dereference_sk_user_data(sk);
67 	if (!bareudp)
68 		goto drop;
69 
70 	if (skb->protocol ==  htons(ETH_P_IP))
71 		family = AF_INET;
72 	else
73 		family = AF_INET6;
74 
75 	if (bareudp->ethertype == htons(ETH_P_IP)) {
76 		struct iphdr *iphdr;
77 
78 		iphdr = (struct iphdr *)(skb->data + BAREUDP_BASE_HLEN);
79 		if (iphdr->version == 4) {
80 			proto = bareudp->ethertype;
81 		} else if (bareudp->multi_proto_mode && (iphdr->version == 6)) {
82 			proto = htons(ETH_P_IPV6);
83 		} else {
84 			bareudp->dev->stats.rx_dropped++;
85 			goto drop;
86 		}
87 	} else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
88 		struct iphdr *tunnel_hdr;
89 
90 		tunnel_hdr = (struct iphdr *)skb_network_header(skb);
91 		if (tunnel_hdr->version == 4) {
92 			if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
93 				proto = bareudp->ethertype;
94 			} else if (bareudp->multi_proto_mode &&
95 				   ipv4_is_multicast(tunnel_hdr->daddr)) {
96 				proto = htons(ETH_P_MPLS_MC);
97 			} else {
98 				bareudp->dev->stats.rx_dropped++;
99 				goto drop;
100 			}
101 		} else {
102 			int addr_type;
103 			struct ipv6hdr *tunnel_hdr_v6;
104 
105 			tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
106 			addr_type =
107 			ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
108 			if (!(addr_type & IPV6_ADDR_MULTICAST)) {
109 				proto = bareudp->ethertype;
110 			} else if (bareudp->multi_proto_mode &&
111 				   (addr_type & IPV6_ADDR_MULTICAST)) {
112 				proto = htons(ETH_P_MPLS_MC);
113 			} else {
114 				bareudp->dev->stats.rx_dropped++;
115 				goto drop;
116 			}
117 		}
118 	} else {
119 		proto = bareudp->ethertype;
120 	}
121 
122 	if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
123 				 proto,
124 				 !net_eq(bareudp->net,
125 				 dev_net(bareudp->dev)))) {
126 		bareudp->dev->stats.rx_dropped++;
127 		goto drop;
128 	}
129 	if (bareudp->rx_collect_metadata) {
130 		tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
131 		if (!tun_dst) {
132 			bareudp->dev->stats.rx_dropped++;
133 			goto drop;
134 		}
135 		skb_dst_set(skb, &tun_dst->dst);
136 	}
137 	skb->dev = bareudp->dev;
138 	oiph = skb_network_header(skb);
139 	skb_reset_network_header(skb);
140 
141 	if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
142 		err = IP_ECN_decapsulate(oiph, skb);
143 	else
144 		err = IP6_ECN_decapsulate(oiph, skb);
145 
146 	if (unlikely(err)) {
147 		if (log_ecn_error) {
148 			if  (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
149 				net_info_ratelimited("non-ECT from %pI4 "
150 						     "with TOS=%#x\n",
151 						     &((struct iphdr *)oiph)->saddr,
152 						     ((struct iphdr *)oiph)->tos);
153 			else
154 				net_info_ratelimited("non-ECT from %pI6\n",
155 						     &((struct ipv6hdr *)oiph)->saddr);
156 		}
157 		if (err > 1) {
158 			++bareudp->dev->stats.rx_frame_errors;
159 			++bareudp->dev->stats.rx_errors;
160 			goto drop;
161 		}
162 	}
163 
164 	len = skb->len;
165 	err = gro_cells_receive(&bareudp->gro_cells, skb);
166 	if (likely(err == NET_RX_SUCCESS)) {
167 		stats = this_cpu_ptr(bareudp->dev->tstats);
168 		u64_stats_update_begin(&stats->syncp);
169 		stats->rx_packets++;
170 		stats->rx_bytes += len;
171 		u64_stats_update_end(&stats->syncp);
172 	}
173 	return 0;
174 drop:
175 	/* Consume bad packet */
176 	kfree_skb(skb);
177 
178 	return 0;
179 }
180 
181 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
182 {
183 	return 0;
184 }
185 
186 static int bareudp_init(struct net_device *dev)
187 {
188 	struct bareudp_dev *bareudp = netdev_priv(dev);
189 	int err;
190 
191 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
192 	if (!dev->tstats)
193 		return -ENOMEM;
194 
195 	err = gro_cells_init(&bareudp->gro_cells, dev);
196 	if (err) {
197 		free_percpu(dev->tstats);
198 		return err;
199 	}
200 	return 0;
201 }
202 
203 static void bareudp_uninit(struct net_device *dev)
204 {
205 	struct bareudp_dev *bareudp = netdev_priv(dev);
206 
207 	gro_cells_destroy(&bareudp->gro_cells);
208 	free_percpu(dev->tstats);
209 }
210 
211 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
212 {
213 	struct udp_port_cfg udp_conf;
214 	struct socket *sock;
215 	int err;
216 
217 	memset(&udp_conf, 0, sizeof(udp_conf));
218 #if IS_ENABLED(CONFIG_IPV6)
219 	udp_conf.family = AF_INET6;
220 #else
221 	udp_conf.family = AF_INET;
222 #endif
223 	udp_conf.local_udp_port = port;
224 	/* Open UDP socket */
225 	err = udp_sock_create(net, &udp_conf, &sock);
226 	if (err < 0)
227 		return ERR_PTR(err);
228 
229 	return sock;
230 }
231 
232 /* Create new listen socket if needed */
233 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
234 {
235 	struct udp_tunnel_sock_cfg tunnel_cfg;
236 	struct socket *sock;
237 
238 	sock = bareudp_create_sock(bareudp->net, port);
239 	if (IS_ERR(sock))
240 		return PTR_ERR(sock);
241 
242 	/* Mark socket as an encapsulation socket */
243 	memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
244 	tunnel_cfg.sk_user_data = bareudp;
245 	tunnel_cfg.encap_type = 1;
246 	tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
247 	tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
248 	tunnel_cfg.encap_destroy = NULL;
249 	setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
250 
251 	/* As the setup_udp_tunnel_sock does not call udp_encap_enable if the
252 	 * socket type is v6 an explicit call to udp_encap_enable is needed.
253 	 */
254 	if (sock->sk->sk_family == AF_INET6)
255 		udp_encap_enable();
256 
257 	rcu_assign_pointer(bareudp->sock, sock);
258 	return 0;
259 }
260 
261 static int bareudp_open(struct net_device *dev)
262 {
263 	struct bareudp_dev *bareudp = netdev_priv(dev);
264 	int ret = 0;
265 
266 	ret =  bareudp_socket_create(bareudp, bareudp->port);
267 	return ret;
268 }
269 
270 static void bareudp_sock_release(struct bareudp_dev *bareudp)
271 {
272 	struct socket *sock;
273 
274 	sock = bareudp->sock;
275 	rcu_assign_pointer(bareudp->sock, NULL);
276 	synchronize_net();
277 	udp_tunnel_sock_release(sock);
278 }
279 
280 static int bareudp_stop(struct net_device *dev)
281 {
282 	struct bareudp_dev *bareudp = netdev_priv(dev);
283 
284 	bareudp_sock_release(bareudp);
285 	return 0;
286 }
287 
288 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
289 			    struct bareudp_dev *bareudp,
290 			    const struct ip_tunnel_info *info)
291 {
292 	bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
293 	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
294 	struct socket *sock = rcu_dereference(bareudp->sock);
295 	bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
296 	const struct ip_tunnel_key *key = &info->key;
297 	struct rtable *rt;
298 	__be16 sport, df;
299 	int min_headroom;
300 	__u8 tos, ttl;
301 	__be32 saddr;
302 	int err;
303 
304 	if (!sock)
305 		return -ESHUTDOWN;
306 
307 	rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
308 				    IPPROTO_UDP, use_cache);
309 
310 	if (IS_ERR(rt))
311 		return PTR_ERR(rt);
312 
313 	skb_tunnel_check_pmtu(skb, &rt->dst,
314 			      BAREUDP_IPV4_HLEN + info->options_len);
315 
316 	sport = udp_flow_src_port(bareudp->net, skb,
317 				  bareudp->sport_min, USHRT_MAX,
318 				  true);
319 	tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
320 	ttl = key->ttl;
321 	df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
322 	skb_scrub_packet(skb, xnet);
323 
324 	err = -ENOSPC;
325 	if (!skb_pull(skb, skb_network_offset(skb)))
326 		goto free_dst;
327 
328 	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
329 		BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
330 
331 	err = skb_cow_head(skb, min_headroom);
332 	if (unlikely(err))
333 		goto free_dst;
334 
335 	err = udp_tunnel_handle_offloads(skb, udp_sum);
336 	if (err)
337 		goto free_dst;
338 
339 	skb_set_inner_protocol(skb, bareudp->ethertype);
340 	udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
341 			    tos, ttl, df, sport, bareudp->port,
342 			    !net_eq(bareudp->net, dev_net(bareudp->dev)),
343 			    !(info->key.tun_flags & TUNNEL_CSUM));
344 	return 0;
345 
346 free_dst:
347 	dst_release(&rt->dst);
348 	return err;
349 }
350 
351 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
352 			     struct bareudp_dev *bareudp,
353 			     const struct ip_tunnel_info *info)
354 {
355 	bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
356 	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
357 	struct socket *sock  = rcu_dereference(bareudp->sock);
358 	bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
359 	const struct ip_tunnel_key *key = &info->key;
360 	struct dst_entry *dst = NULL;
361 	struct in6_addr saddr, daddr;
362 	int min_headroom;
363 	__u8 prio, ttl;
364 	__be16 sport;
365 	int err;
366 
367 	if (!sock)
368 		return -ESHUTDOWN;
369 
370 	dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
371 				    IPPROTO_UDP, use_cache);
372 	if (IS_ERR(dst))
373 		return PTR_ERR(dst);
374 
375 	skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len);
376 
377 	sport = udp_flow_src_port(bareudp->net, skb,
378 				  bareudp->sport_min, USHRT_MAX,
379 				  true);
380 	prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
381 	ttl = key->ttl;
382 
383 	skb_scrub_packet(skb, xnet);
384 
385 	err = -ENOSPC;
386 	if (!skb_pull(skb, skb_network_offset(skb)))
387 		goto free_dst;
388 
389 	min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
390 		BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
391 
392 	err = skb_cow_head(skb, min_headroom);
393 	if (unlikely(err))
394 		goto free_dst;
395 
396 	err = udp_tunnel_handle_offloads(skb, udp_sum);
397 	if (err)
398 		goto free_dst;
399 
400 	daddr = info->key.u.ipv6.dst;
401 	udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
402 			     &saddr, &daddr, prio, ttl,
403 			     info->key.label, sport, bareudp->port,
404 			     !(info->key.tun_flags & TUNNEL_CSUM));
405 	return 0;
406 
407 free_dst:
408 	dst_release(dst);
409 	return err;
410 }
411 
412 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
413 {
414 	struct bareudp_dev *bareudp = netdev_priv(dev);
415 	struct ip_tunnel_info *info = NULL;
416 	int err;
417 
418 	if (skb->protocol != bareudp->ethertype) {
419 		if (!bareudp->multi_proto_mode ||
420 		    (skb->protocol !=  htons(ETH_P_MPLS_MC) &&
421 		     skb->protocol !=  htons(ETH_P_IPV6))) {
422 			err = -EINVAL;
423 			goto tx_error;
424 		}
425 	}
426 
427 	info = skb_tunnel_info(skb);
428 	if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
429 		err = -EINVAL;
430 		goto tx_error;
431 	}
432 
433 	rcu_read_lock();
434 	if (IS_ENABLED(CONFIG_IPV6) && info->mode & IP_TUNNEL_INFO_IPV6)
435 		err = bareudp6_xmit_skb(skb, dev, bareudp, info);
436 	else
437 		err = bareudp_xmit_skb(skb, dev, bareudp, info);
438 
439 	rcu_read_unlock();
440 
441 	if (likely(!err))
442 		return NETDEV_TX_OK;
443 tx_error:
444 	dev_kfree_skb(skb);
445 
446 	if (err == -ELOOP)
447 		dev->stats.collisions++;
448 	else if (err == -ENETUNREACH)
449 		dev->stats.tx_carrier_errors++;
450 
451 	dev->stats.tx_errors++;
452 	return NETDEV_TX_OK;
453 }
454 
455 static int bareudp_fill_metadata_dst(struct net_device *dev,
456 				     struct sk_buff *skb)
457 {
458 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
459 	struct bareudp_dev *bareudp = netdev_priv(dev);
460 	bool use_cache;
461 
462 	use_cache = ip_tunnel_dst_cache_usable(skb, info);
463 
464 	if (!IS_ENABLED(CONFIG_IPV6) || ip_tunnel_info_af(info) == AF_INET) {
465 		struct rtable *rt;
466 		__be32 saddr;
467 
468 		rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
469 					    info, IPPROTO_UDP, use_cache);
470 		if (IS_ERR(rt))
471 			return PTR_ERR(rt);
472 
473 		ip_rt_put(rt);
474 		info->key.u.ipv4.src = saddr;
475 	} else if (ip_tunnel_info_af(info) == AF_INET6) {
476 		struct dst_entry *dst;
477 		struct in6_addr saddr;
478 		struct socket *sock = rcu_dereference(bareudp->sock);
479 
480 		dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
481 					    &saddr, info, IPPROTO_UDP,
482 					    use_cache);
483 		if (IS_ERR(dst))
484 			return PTR_ERR(dst);
485 
486 		dst_release(dst);
487 		info->key.u.ipv6.src = saddr;
488 	} else {
489 		return -EINVAL;
490 	}
491 
492 	info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
493 					     bareudp->sport_min,
494 			USHRT_MAX, true);
495 	info->key.tp_dst = bareudp->port;
496 	return 0;
497 }
498 
499 static const struct net_device_ops bareudp_netdev_ops = {
500 	.ndo_init               = bareudp_init,
501 	.ndo_uninit             = bareudp_uninit,
502 	.ndo_open               = bareudp_open,
503 	.ndo_stop               = bareudp_stop,
504 	.ndo_start_xmit         = bareudp_xmit,
505 	.ndo_get_stats64        = ip_tunnel_get_stats64,
506 	.ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
507 };
508 
509 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
510 	[IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
511 	[IFLA_BAREUDP_ETHERTYPE]	   = { .type = NLA_U16 },
512 	[IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
513 	[IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
514 };
515 
516 /* Info for udev, that this is a virtual tunnel endpoint */
517 static struct device_type bareudp_type = {
518 	.name = "bareudp",
519 };
520 
521 /* Initialize the device structure. */
522 static void bareudp_setup(struct net_device *dev)
523 {
524 	dev->netdev_ops = &bareudp_netdev_ops;
525 	dev->needs_free_netdev = true;
526 	SET_NETDEV_DEVTYPE(dev, &bareudp_type);
527 	dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
528 	dev->features    |= NETIF_F_RXCSUM;
529 	dev->features    |= NETIF_F_GSO_SOFTWARE;
530 	dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
531 	dev->hw_features |= NETIF_F_GSO_SOFTWARE;
532 	dev->hard_header_len = 0;
533 	dev->addr_len = 0;
534 	dev->mtu = ETH_DATA_LEN;
535 	dev->min_mtu = IPV4_MIN_MTU;
536 	dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
537 	dev->type = ARPHRD_NONE;
538 	netif_keep_dst(dev);
539 	dev->priv_flags |= IFF_NO_QUEUE;
540 	dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
541 }
542 
543 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
544 			    struct netlink_ext_ack *extack)
545 {
546 	if (!data) {
547 		NL_SET_ERR_MSG(extack,
548 			       "Not enough attributes provided to perform the operation");
549 		return -EINVAL;
550 	}
551 	return 0;
552 }
553 
554 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
555 			struct netlink_ext_ack *extack)
556 {
557 	memset(conf, 0, sizeof(*conf));
558 
559 	if (!data[IFLA_BAREUDP_PORT]) {
560 		NL_SET_ERR_MSG(extack, "port not specified");
561 		return -EINVAL;
562 	}
563 	if (!data[IFLA_BAREUDP_ETHERTYPE]) {
564 		NL_SET_ERR_MSG(extack, "ethertype not specified");
565 		return -EINVAL;
566 	}
567 
568 	if (data[IFLA_BAREUDP_PORT])
569 		conf->port =  nla_get_u16(data[IFLA_BAREUDP_PORT]);
570 
571 	if (data[IFLA_BAREUDP_ETHERTYPE])
572 		conf->ethertype =  nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
573 
574 	if (data[IFLA_BAREUDP_SRCPORT_MIN])
575 		conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
576 
577 	if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
578 		conf->multi_proto_mode = true;
579 
580 	if (data[IFLA_BAREUDP_RX_COLLECT_METADATA])
581 		conf->rx_collect_metadata = true;
582 
583 	return 0;
584 }
585 
586 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
587 					    const struct bareudp_conf *conf)
588 {
589 	struct bareudp_dev *bareudp, *t = NULL;
590 
591 	list_for_each_entry(bareudp, &bn->bareudp_list, next) {
592 		if (conf->port == bareudp->port)
593 			t = bareudp;
594 	}
595 	return t;
596 }
597 
598 static int bareudp_configure(struct net *net, struct net_device *dev,
599 			     struct bareudp_conf *conf)
600 {
601 	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
602 	struct bareudp_dev *t, *bareudp = netdev_priv(dev);
603 	int err;
604 
605 	bareudp->net = net;
606 	bareudp->dev = dev;
607 	t = bareudp_find_dev(bn, conf);
608 	if (t)
609 		return -EBUSY;
610 
611 	if (conf->multi_proto_mode &&
612 	    (conf->ethertype != htons(ETH_P_MPLS_UC) &&
613 	     conf->ethertype != htons(ETH_P_IP)))
614 		return -EINVAL;
615 
616 	bareudp->port = conf->port;
617 	bareudp->ethertype = conf->ethertype;
618 	bareudp->sport_min = conf->sport_min;
619 	bareudp->multi_proto_mode = conf->multi_proto_mode;
620 	bareudp->rx_collect_metadata = conf->rx_collect_metadata;
621 
622 	err = register_netdevice(dev);
623 	if (err)
624 		return err;
625 
626 	list_add(&bareudp->next, &bn->bareudp_list);
627 	return 0;
628 }
629 
630 static int bareudp_link_config(struct net_device *dev,
631 			       struct nlattr *tb[])
632 {
633 	int err;
634 
635 	if (tb[IFLA_MTU]) {
636 		err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
637 		if (err)
638 			return err;
639 	}
640 	return 0;
641 }
642 
643 static int bareudp_newlink(struct net *net, struct net_device *dev,
644 			   struct nlattr *tb[], struct nlattr *data[],
645 			   struct netlink_ext_ack *extack)
646 {
647 	struct bareudp_conf conf;
648 	int err;
649 
650 	err = bareudp2info(data, &conf, extack);
651 	if (err)
652 		return err;
653 
654 	err = bareudp_configure(net, dev, &conf);
655 	if (err)
656 		return err;
657 
658 	err = bareudp_link_config(dev, tb);
659 	if (err)
660 		return err;
661 
662 	return 0;
663 }
664 
665 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
666 {
667 	struct bareudp_dev *bareudp = netdev_priv(dev);
668 
669 	list_del(&bareudp->next);
670 	unregister_netdevice_queue(dev, head);
671 }
672 
673 static size_t bareudp_get_size(const struct net_device *dev)
674 {
675 	return  nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_PORT */
676 		nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_ETHERTYPE */
677 		nla_total_size(sizeof(__u16))  +  /* IFLA_BAREUDP_SRCPORT_MIN */
678 		nla_total_size(0)              +  /* IFLA_BAREUDP_MULTIPROTO_MODE */
679 		nla_total_size(0)              +  /* IFLA_BAREUDP_RX_COLLECT_METADATA */
680 		0;
681 }
682 
683 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
684 {
685 	struct bareudp_dev *bareudp = netdev_priv(dev);
686 
687 	if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
688 		goto nla_put_failure;
689 	if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
690 		goto nla_put_failure;
691 	if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
692 		goto nla_put_failure;
693 	if (bareudp->multi_proto_mode &&
694 	    nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
695 		goto nla_put_failure;
696 	if (bareudp->rx_collect_metadata &&
697 	    nla_put_flag(skb, IFLA_BAREUDP_RX_COLLECT_METADATA))
698 		goto nla_put_failure;
699 
700 	return 0;
701 
702 nla_put_failure:
703 	return -EMSGSIZE;
704 }
705 
706 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
707 	.kind           = "bareudp",
708 	.maxtype        = IFLA_BAREUDP_MAX,
709 	.policy         = bareudp_policy,
710 	.priv_size      = sizeof(struct bareudp_dev),
711 	.setup          = bareudp_setup,
712 	.validate       = bareudp_validate,
713 	.newlink        = bareudp_newlink,
714 	.dellink        = bareudp_dellink,
715 	.get_size       = bareudp_get_size,
716 	.fill_info      = bareudp_fill_info,
717 };
718 
719 struct net_device *bareudp_dev_create(struct net *net, const char *name,
720 				      u8 name_assign_type,
721 				      struct bareudp_conf *conf)
722 {
723 	struct nlattr *tb[IFLA_MAX + 1];
724 	struct net_device *dev;
725 	LIST_HEAD(list_kill);
726 	int err;
727 
728 	memset(tb, 0, sizeof(tb));
729 	dev = rtnl_create_link(net, name, name_assign_type,
730 			       &bareudp_link_ops, tb, NULL);
731 	if (IS_ERR(dev))
732 		return dev;
733 
734 	err = bareudp_configure(net, dev, conf);
735 	if (err) {
736 		free_netdev(dev);
737 		return ERR_PTR(err);
738 	}
739 	err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
740 	if (err)
741 		goto err;
742 
743 	err = rtnl_configure_link(dev, NULL);
744 	if (err < 0)
745 		goto err;
746 
747 	return dev;
748 err:
749 	bareudp_dellink(dev, &list_kill);
750 	unregister_netdevice_many(&list_kill);
751 	return ERR_PTR(err);
752 }
753 EXPORT_SYMBOL_GPL(bareudp_dev_create);
754 
755 static __net_init int bareudp_init_net(struct net *net)
756 {
757 	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
758 
759 	INIT_LIST_HEAD(&bn->bareudp_list);
760 	return 0;
761 }
762 
763 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
764 {
765 	struct bareudp_net *bn = net_generic(net, bareudp_net_id);
766 	struct bareudp_dev *bareudp, *next;
767 
768 	list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
769 		unregister_netdevice_queue(bareudp->dev, head);
770 }
771 
772 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
773 {
774 	struct net *net;
775 	LIST_HEAD(list);
776 
777 	rtnl_lock();
778 	list_for_each_entry(net, net_list, exit_list)
779 		bareudp_destroy_tunnels(net, &list);
780 
781 	/* unregister the devices gathered above */
782 	unregister_netdevice_many(&list);
783 	rtnl_unlock();
784 }
785 
786 static struct pernet_operations bareudp_net_ops = {
787 	.init = bareudp_init_net,
788 	.exit_batch = bareudp_exit_batch_net,
789 	.id   = &bareudp_net_id,
790 	.size = sizeof(struct bareudp_net),
791 };
792 
793 static int __init bareudp_init_module(void)
794 {
795 	int rc;
796 
797 	rc = register_pernet_subsys(&bareudp_net_ops);
798 	if (rc)
799 		goto out1;
800 
801 	rc = rtnl_link_register(&bareudp_link_ops);
802 	if (rc)
803 		goto out2;
804 
805 	return 0;
806 out2:
807 	unregister_pernet_subsys(&bareudp_net_ops);
808 out1:
809 	return rc;
810 }
811 late_initcall(bareudp_init_module);
812 
813 static void __exit bareudp_cleanup_module(void)
814 {
815 	rtnl_link_unregister(&bareudp_link_ops);
816 	unregister_pernet_subsys(&bareudp_net_ops);
817 }
818 module_exit(bareudp_cleanup_module);
819 
820 MODULE_ALIAS_RTNL_LINK("bareudp");
821 MODULE_LICENSE("GPL");
822 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
823 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");
824