• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* net/tipc/udp_media.c: IP bearer support for TIPC
2  *
3  * Copyright (c) 2015, Ericsson AB
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the names of the copyright holders nor the names of its
15  *    contributors may be used to endorse or promote products derived from
16  *    this software without specific prior written permission.
17  *
18  * Alternatively, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2 as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <linux/socket.h>
36 #include <linux/ip.h>
37 #include <linux/udp.h>
38 #include <linux/inet.h>
39 #include <linux/inetdevice.h>
40 #include <linux/igmp.h>
41 #include <linux/kernel.h>
42 #include <linux/workqueue.h>
43 #include <linux/list.h>
44 #include <net/sock.h>
45 #include <net/ip.h>
46 #include <net/udp_tunnel.h>
47 #include <net/ipv6_stubs.h>
48 #include <linux/tipc_netlink.h>
49 #include "core.h"
50 #include "addr.h"
51 #include "net.h"
52 #include "bearer.h"
53 #include "netlink.h"
54 #include "msg.h"
55 #include "udp_media.h"
56 
57 /* IANA assigned UDP port */
58 #define UDP_PORT_DEFAULT	6118
59 
60 #define UDP_MIN_HEADROOM        48
61 
62 /**
63  * struct udp_media_addr - IP/UDP addressing information
64  *
65  * This is the bearer level originating address used in neighbor discovery
66  * messages, and all fields should be in network byte order
67  */
68 struct udp_media_addr {
69 	__be16	proto;
70 	__be16	port;
71 	union {
72 		struct in_addr ipv4;
73 		struct in6_addr ipv6;
74 	};
75 };
76 
77 /* struct udp_replicast - container for UDP remote addresses */
78 struct udp_replicast {
79 	struct udp_media_addr addr;
80 	struct dst_cache dst_cache;
81 	struct rcu_head rcu;
82 	struct list_head list;
83 };
84 
85 /**
86  * struct udp_bearer - ip/udp bearer data structure
87  * @bearer:	associated generic tipc bearer
88  * @ubsock:	bearer associated socket
89  * @ifindex:	local address scope
90  * @work:	used to schedule deferred work on a bearer
91  */
92 struct udp_bearer {
93 	struct tipc_bearer __rcu *bearer;
94 	struct socket *ubsock;
95 	u32 ifindex;
96 	struct work_struct work;
97 	struct udp_replicast rcast;
98 };
99 
tipc_udp_is_mcast_addr(struct udp_media_addr * addr)100 static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
101 {
102 	if (ntohs(addr->proto) == ETH_P_IP)
103 		return ipv4_is_multicast(addr->ipv4.s_addr);
104 #if IS_ENABLED(CONFIG_IPV6)
105 	else
106 		return ipv6_addr_is_multicast(&addr->ipv6);
107 #endif
108 	return 0;
109 }
110 
111 /* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
tipc_udp_media_addr_set(struct tipc_media_addr * addr,struct udp_media_addr * ua)112 static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
113 				    struct udp_media_addr *ua)
114 {
115 	memset(addr, 0, sizeof(struct tipc_media_addr));
116 	addr->media_id = TIPC_MEDIA_TYPE_UDP;
117 	memcpy(addr->value, ua, sizeof(struct udp_media_addr));
118 
119 	if (tipc_udp_is_mcast_addr(ua))
120 		addr->broadcast = TIPC_BROADCAST_SUPPORT;
121 }
122 
123 /* tipc_udp_addr2str - convert ip/udp address to string */
tipc_udp_addr2str(struct tipc_media_addr * a,char * buf,int size)124 static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
125 {
126 	struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
127 
128 	if (ntohs(ua->proto) == ETH_P_IP)
129 		snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
130 	else if (ntohs(ua->proto) == ETH_P_IPV6)
131 		snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
132 	else
133 		pr_err("Invalid UDP media address\n");
134 	return 0;
135 }
136 
137 /* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
tipc_udp_msg2addr(struct tipc_bearer * b,struct tipc_media_addr * a,char * msg)138 static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
139 			     char *msg)
140 {
141 	struct udp_media_addr *ua;
142 
143 	ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
144 	if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
145 		return -EINVAL;
146 	tipc_udp_media_addr_set(a, ua);
147 	return 0;
148 }
149 
150 /* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
tipc_udp_addr2msg(char * msg,struct tipc_media_addr * a)151 static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
152 {
153 	memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
154 	msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
155 	memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
156 	       sizeof(struct udp_media_addr));
157 	return 0;
158 }
159 
160 /* tipc_send_msg - enqueue a send request */
tipc_udp_xmit(struct net * net,struct sk_buff * skb,struct udp_bearer * ub,struct udp_media_addr * src,struct udp_media_addr * dst,struct dst_cache * cache)161 static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
162 			 struct udp_bearer *ub, struct udp_media_addr *src,
163 			 struct udp_media_addr *dst, struct dst_cache *cache)
164 {
165 	struct dst_entry *ndst;
166 	int ttl, err = 0;
167 
168 	local_bh_disable();
169 	ndst = dst_cache_get(cache);
170 	if (dst->proto == htons(ETH_P_IP)) {
171 		struct rtable *rt = (struct rtable *)ndst;
172 
173 		if (!rt) {
174 			struct flowi4 fl = {
175 				.daddr = dst->ipv4.s_addr,
176 				.saddr = src->ipv4.s_addr,
177 				.flowi4_mark = skb->mark,
178 				.flowi4_proto = IPPROTO_UDP
179 			};
180 			rt = ip_route_output_key(net, &fl);
181 			if (IS_ERR(rt)) {
182 				err = PTR_ERR(rt);
183 				goto tx_error;
184 			}
185 			dst_cache_set_ip4(cache, &rt->dst, fl.saddr);
186 		}
187 
188 		ttl = ip4_dst_hoplimit(&rt->dst);
189 		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
190 				    dst->ipv4.s_addr, 0, ttl, 0, src->port,
191 				    dst->port, false, true);
192 #if IS_ENABLED(CONFIG_IPV6)
193 	} else {
194 		if (!ndst) {
195 			struct flowi6 fl6 = {
196 				.flowi6_oif = ub->ifindex,
197 				.daddr = dst->ipv6,
198 				.saddr = src->ipv6,
199 				.flowi6_proto = IPPROTO_UDP
200 			};
201 			ndst = ipv6_stub->ipv6_dst_lookup_flow(net,
202 							       ub->ubsock->sk,
203 							       &fl6, NULL);
204 			if (IS_ERR(ndst)) {
205 				err = PTR_ERR(ndst);
206 				goto tx_error;
207 			}
208 			dst_cache_set_ip6(cache, ndst, &fl6.saddr);
209 		}
210 		ttl = ip6_dst_hoplimit(ndst);
211 		err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
212 					   &src->ipv6, &dst->ipv6, 0, ttl, 0,
213 					   src->port, dst->port, false);
214 #endif
215 	}
216 	local_bh_enable();
217 	return err;
218 
219 tx_error:
220 	local_bh_enable();
221 	kfree_skb(skb);
222 	return err;
223 }
224 
tipc_udp_send_msg(struct net * net,struct sk_buff * skb,struct tipc_bearer * b,struct tipc_media_addr * addr)225 static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
226 			     struct tipc_bearer *b,
227 			     struct tipc_media_addr *addr)
228 {
229 	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
230 	struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
231 	struct udp_replicast *rcast;
232 	struct udp_bearer *ub;
233 	int err = 0;
234 
235 	if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
236 		err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
237 		if (err)
238 			goto out;
239 	}
240 
241 	skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
242 	ub = rcu_dereference(b->media_ptr);
243 	if (!ub) {
244 		err = -ENODEV;
245 		goto out;
246 	}
247 
248 	if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
249 		return tipc_udp_xmit(net, skb, ub, src, dst,
250 				     &ub->rcast.dst_cache);
251 
252 	/* Replicast, send an skb to each configured IP address */
253 	list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
254 		struct sk_buff *_skb;
255 
256 		_skb = pskb_copy(skb, GFP_ATOMIC);
257 		if (!_skb) {
258 			err = -ENOMEM;
259 			goto out;
260 		}
261 
262 		err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr,
263 				    &rcast->dst_cache);
264 		if (err)
265 			goto out;
266 	}
267 	err = 0;
268 out:
269 	kfree_skb(skb);
270 	return err;
271 }
272 
tipc_udp_is_known_peer(struct tipc_bearer * b,struct udp_media_addr * addr)273 static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
274 				   struct udp_media_addr *addr)
275 {
276 	struct udp_replicast *rcast, *tmp;
277 	struct udp_bearer *ub;
278 
279 	ub = rcu_dereference_rtnl(b->media_ptr);
280 	if (!ub) {
281 		pr_err_ratelimited("UDP bearer instance not found\n");
282 		return false;
283 	}
284 
285 	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
286 		if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
287 			return true;
288 	}
289 
290 	return false;
291 }
292 
tipc_udp_rcast_add(struct tipc_bearer * b,struct udp_media_addr * addr)293 static int tipc_udp_rcast_add(struct tipc_bearer *b,
294 			      struct udp_media_addr *addr)
295 {
296 	struct udp_replicast *rcast;
297 	struct udp_bearer *ub;
298 
299 	ub = rcu_dereference_rtnl(b->media_ptr);
300 	if (!ub)
301 		return -ENODEV;
302 
303 	rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
304 	if (!rcast)
305 		return -ENOMEM;
306 
307 	if (dst_cache_init(&rcast->dst_cache, GFP_ATOMIC)) {
308 		kfree(rcast);
309 		return -ENOMEM;
310 	}
311 
312 	memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
313 
314 	if (ntohs(addr->proto) == ETH_P_IP)
315 		pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
316 #if IS_ENABLED(CONFIG_IPV6)
317 	else if (ntohs(addr->proto) == ETH_P_IPV6)
318 		pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
319 #endif
320 	b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
321 	list_add_rcu(&rcast->list, &ub->rcast.list);
322 	return 0;
323 }
324 
tipc_udp_rcast_disc(struct tipc_bearer * b,struct sk_buff * skb)325 static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
326 {
327 	struct udp_media_addr src = {0};
328 	struct udp_media_addr *dst;
329 
330 	dst = (struct udp_media_addr *)&b->bcast_addr.value;
331 	if (tipc_udp_is_mcast_addr(dst))
332 		return 0;
333 
334 	src.port = udp_hdr(skb)->source;
335 
336 	if (ip_hdr(skb)->version == 4) {
337 		struct iphdr *iphdr = ip_hdr(skb);
338 
339 		src.proto = htons(ETH_P_IP);
340 		src.ipv4.s_addr = iphdr->saddr;
341 		if (ipv4_is_multicast(iphdr->daddr))
342 			return 0;
343 #if IS_ENABLED(CONFIG_IPV6)
344 	} else if (ip_hdr(skb)->version == 6) {
345 		struct ipv6hdr *iphdr = ipv6_hdr(skb);
346 
347 		src.proto = htons(ETH_P_IPV6);
348 		src.ipv6 = iphdr->saddr;
349 		if (ipv6_addr_is_multicast(&iphdr->daddr))
350 			return 0;
351 #endif
352 	} else {
353 		return 0;
354 	}
355 
356 	if (likely(tipc_udp_is_known_peer(b, &src)))
357 		return 0;
358 
359 	return tipc_udp_rcast_add(b, &src);
360 }
361 
362 /* tipc_udp_recv - read data from bearer socket */
tipc_udp_recv(struct sock * sk,struct sk_buff * skb)363 static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
364 {
365 	struct udp_bearer *ub;
366 	struct tipc_bearer *b;
367 	struct tipc_msg *hdr;
368 	int err;
369 
370 	ub = rcu_dereference_sk_user_data(sk);
371 	if (!ub) {
372 		pr_err_ratelimited("Failed to get UDP bearer reference");
373 		goto out;
374 	}
375 	skb_pull(skb, sizeof(struct udphdr));
376 	hdr = buf_msg(skb);
377 
378 	b = rcu_dereference(ub->bearer);
379 	if (!b)
380 		goto out;
381 
382 	if (b && test_bit(0, &b->up)) {
383 		TIPC_SKB_CB(skb)->flags = 0;
384 		tipc_rcv(sock_net(sk), skb, b);
385 		return 0;
386 	}
387 
388 	if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
389 		err = tipc_udp_rcast_disc(b, skb);
390 		if (err)
391 			goto out;
392 	}
393 
394 out:
395 	kfree_skb(skb);
396 	return 0;
397 }
398 
enable_mcast(struct udp_bearer * ub,struct udp_media_addr * remote)399 static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
400 {
401 	int err = 0;
402 	struct ip_mreqn mreqn;
403 	struct sock *sk = ub->ubsock->sk;
404 
405 	if (ntohs(remote->proto) == ETH_P_IP) {
406 		mreqn.imr_multiaddr = remote->ipv4;
407 		mreqn.imr_ifindex = ub->ifindex;
408 		err = ip_mc_join_group(sk, &mreqn);
409 #if IS_ENABLED(CONFIG_IPV6)
410 	} else {
411 		err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
412 						   &remote->ipv6);
413 #endif
414 	}
415 	return err;
416 }
417 
__tipc_nl_add_udp_addr(struct sk_buff * skb,struct udp_media_addr * addr,int nla_t)418 static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
419 				  struct udp_media_addr *addr, int nla_t)
420 {
421 	if (ntohs(addr->proto) == ETH_P_IP) {
422 		struct sockaddr_in ip4;
423 
424 		memset(&ip4, 0, sizeof(ip4));
425 		ip4.sin_family = AF_INET;
426 		ip4.sin_port = addr->port;
427 		ip4.sin_addr.s_addr = addr->ipv4.s_addr;
428 		if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
429 			return -EMSGSIZE;
430 
431 #if IS_ENABLED(CONFIG_IPV6)
432 	} else if (ntohs(addr->proto) == ETH_P_IPV6) {
433 		struct sockaddr_in6 ip6;
434 
435 		memset(&ip6, 0, sizeof(ip6));
436 		ip6.sin6_family = AF_INET6;
437 		ip6.sin6_port  = addr->port;
438 		memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
439 		if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
440 			return -EMSGSIZE;
441 #endif
442 	}
443 
444 	return 0;
445 }
446 
tipc_udp_nl_dump_remoteip(struct sk_buff * skb,struct netlink_callback * cb)447 int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
448 {
449 	u32 bid = cb->args[0];
450 	u32 skip_cnt = cb->args[1];
451 	u32 portid = NETLINK_CB(cb->skb).portid;
452 	struct udp_replicast *rcast, *tmp;
453 	struct tipc_bearer *b;
454 	struct udp_bearer *ub;
455 	void *hdr;
456 	int err;
457 	int i;
458 
459 	if (!bid && !skip_cnt) {
460 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
461 		struct net *net = sock_net(skb->sk);
462 		struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
463 		char *bname;
464 
465 		if (!attrs[TIPC_NLA_BEARER])
466 			return -EINVAL;
467 
468 		err = nla_parse_nested_deprecated(battrs, TIPC_NLA_BEARER_MAX,
469 						  attrs[TIPC_NLA_BEARER],
470 						  tipc_nl_bearer_policy, NULL);
471 		if (err)
472 			return err;
473 
474 		if (!battrs[TIPC_NLA_BEARER_NAME])
475 			return -EINVAL;
476 
477 		bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
478 
479 		rtnl_lock();
480 		b = tipc_bearer_find(net, bname);
481 		if (!b) {
482 			rtnl_unlock();
483 			return -EINVAL;
484 		}
485 		bid = b->identity;
486 	} else {
487 		struct net *net = sock_net(skb->sk);
488 		struct tipc_net *tn = net_generic(net, tipc_net_id);
489 
490 		rtnl_lock();
491 		b = rtnl_dereference(tn->bearer_list[bid]);
492 		if (!b) {
493 			rtnl_unlock();
494 			return -EINVAL;
495 		}
496 	}
497 
498 	ub = rtnl_dereference(b->media_ptr);
499 	if (!ub) {
500 		rtnl_unlock();
501 		return -EINVAL;
502 	}
503 
504 	i = 0;
505 	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
506 		if (i < skip_cnt)
507 			goto count;
508 
509 		hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
510 				  &tipc_genl_family, NLM_F_MULTI,
511 				  TIPC_NL_BEARER_GET);
512 		if (!hdr)
513 			goto done;
514 
515 		err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
516 					     TIPC_NLA_UDP_REMOTE);
517 		if (err) {
518 			genlmsg_cancel(skb, hdr);
519 			goto done;
520 		}
521 		genlmsg_end(skb, hdr);
522 count:
523 		i++;
524 	}
525 done:
526 	rtnl_unlock();
527 	cb->args[0] = bid;
528 	cb->args[1] = i;
529 
530 	return skb->len;
531 }
532 
tipc_udp_nl_add_bearer_data(struct tipc_nl_msg * msg,struct tipc_bearer * b)533 int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
534 {
535 	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
536 	struct udp_media_addr *dst;
537 	struct udp_bearer *ub;
538 	struct nlattr *nest;
539 
540 	ub = rtnl_dereference(b->media_ptr);
541 	if (!ub)
542 		return -ENODEV;
543 
544 	nest = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
545 	if (!nest)
546 		goto msg_full;
547 
548 	if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
549 		goto msg_full;
550 
551 	dst = (struct udp_media_addr *)&b->bcast_addr.value;
552 	if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
553 		goto msg_full;
554 
555 	if (!list_empty(&ub->rcast.list)) {
556 		if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
557 			goto msg_full;
558 	}
559 
560 	nla_nest_end(msg->skb, nest);
561 	return 0;
562 msg_full:
563 	nla_nest_cancel(msg->skb, nest);
564 	return -EMSGSIZE;
565 }
566 
567 /**
568  * tipc_parse_udp_addr - build udp media address from netlink data
569  * @nla:	netlink attribute containing sockaddr storage aligned address
570  * @addr:	tipc media address to fill with address, port and protocol type
571  * @scope_id:	IPv6 scope id pointer, not NULL indicates it's required
572  */
573 
tipc_parse_udp_addr(struct nlattr * nla,struct udp_media_addr * addr,u32 * scope_id)574 static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
575 			       u32 *scope_id)
576 {
577 	struct sockaddr_storage sa;
578 
579 	nla_memcpy(&sa, nla, sizeof(sa));
580 	if (sa.ss_family == AF_INET) {
581 		struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
582 
583 		addr->proto = htons(ETH_P_IP);
584 		addr->port = ip4->sin_port;
585 		addr->ipv4.s_addr = ip4->sin_addr.s_addr;
586 		return 0;
587 
588 #if IS_ENABLED(CONFIG_IPV6)
589 	} else if (sa.ss_family == AF_INET6) {
590 		struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
591 
592 		addr->proto = htons(ETH_P_IPV6);
593 		addr->port = ip6->sin6_port;
594 		memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
595 
596 		/* Scope ID is only interesting for local addresses */
597 		if (scope_id) {
598 			int atype;
599 
600 			atype = ipv6_addr_type(&ip6->sin6_addr);
601 			if (__ipv6_addr_needs_scope_id(atype) &&
602 			    !ip6->sin6_scope_id) {
603 				return -EINVAL;
604 			}
605 
606 			*scope_id = ip6->sin6_scope_id ? : 0;
607 		}
608 
609 		return 0;
610 #endif
611 	}
612 	return -EADDRNOTAVAIL;
613 }
614 
tipc_udp_nl_bearer_add(struct tipc_bearer * b,struct nlattr * attr)615 int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
616 {
617 	int err;
618 	struct udp_media_addr addr = {0};
619 	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
620 	struct udp_media_addr *dst;
621 
622 	if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attr, tipc_nl_udp_policy, NULL))
623 		return -EINVAL;
624 
625 	if (!opts[TIPC_NLA_UDP_REMOTE])
626 		return -EINVAL;
627 
628 	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
629 	if (err)
630 		return err;
631 
632 	dst = (struct udp_media_addr *)&b->bcast_addr.value;
633 	if (tipc_udp_is_mcast_addr(dst)) {
634 		pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
635 		return -EINVAL;
636 	}
637 
638 	if (tipc_udp_is_known_peer(b, &addr))
639 		return 0;
640 
641 	return tipc_udp_rcast_add(b, &addr);
642 }
643 
644 /**
645  * tipc_udp_enable - callback to create a new udp bearer instance
646  * @net:	network namespace
647  * @b:		pointer to generic tipc_bearer
648  * @attrs:	netlink bearer configuration
649  *
650  * validate the bearer parameters and initialize the udp bearer
651  * rtnl_lock should be held
652  */
tipc_udp_enable(struct net * net,struct tipc_bearer * b,struct nlattr * attrs[])653 static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
654 			   struct nlattr *attrs[])
655 {
656 	int err = -EINVAL;
657 	struct udp_bearer *ub;
658 	struct udp_media_addr remote = {0};
659 	struct udp_media_addr local = {0};
660 	struct udp_port_cfg udp_conf = {0};
661 	struct udp_tunnel_sock_cfg tuncfg = {NULL};
662 	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
663 	u8 node_id[NODE_ID_LEN] = {0,};
664 	struct net_device *dev;
665 	int rmcast = 0;
666 
667 	ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
668 	if (!ub)
669 		return -ENOMEM;
670 
671 	INIT_LIST_HEAD(&ub->rcast.list);
672 
673 	if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
674 		goto err;
675 
676 	if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attrs[TIPC_NLA_BEARER_UDP_OPTS], tipc_nl_udp_policy, NULL))
677 		goto err;
678 
679 	if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
680 		pr_err("Invalid UDP bearer configuration");
681 		err = -EINVAL;
682 		goto err;
683 	}
684 
685 	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
686 				  &ub->ifindex);
687 	if (err)
688 		goto err;
689 
690 	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
691 	if (err)
692 		goto err;
693 
694 	if (remote.proto != local.proto) {
695 		err = -EINVAL;
696 		goto err;
697 	}
698 
699 	/* Checking remote ip address */
700 	rmcast = tipc_udp_is_mcast_addr(&remote);
701 
702 	/* Autoconfigure own node identity if needed */
703 	if (!tipc_own_id(net)) {
704 		memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
705 		tipc_net_init(net, node_id, 0);
706 	}
707 	if (!tipc_own_id(net)) {
708 		pr_warn("Failed to set node id, please configure manually\n");
709 		err = -EINVAL;
710 		goto err;
711 	}
712 
713 	b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
714 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
715 	rcu_assign_pointer(b->media_ptr, ub);
716 	rcu_assign_pointer(ub->bearer, b);
717 	tipc_udp_media_addr_set(&b->addr, &local);
718 	if (local.proto == htons(ETH_P_IP)) {
719 		dev = __ip_dev_find(net, local.ipv4.s_addr, false);
720 		if (!dev) {
721 			err = -ENODEV;
722 			goto err;
723 		}
724 		udp_conf.family = AF_INET;
725 
726 		/* Switch to use ANY to receive packets from group */
727 		if (rmcast)
728 			udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
729 		else
730 			udp_conf.local_ip.s_addr = local.ipv4.s_addr;
731 		udp_conf.use_udp_checksums = false;
732 		ub->ifindex = dev->ifindex;
733 		if (tipc_mtu_bad(dev, sizeof(struct iphdr) +
734 				      sizeof(struct udphdr))) {
735 			err = -EINVAL;
736 			goto err;
737 		}
738 		b->mtu = b->media->mtu;
739 #if IS_ENABLED(CONFIG_IPV6)
740 	} else if (local.proto == htons(ETH_P_IPV6)) {
741 		dev = ub->ifindex ? __dev_get_by_index(net, ub->ifindex) : NULL;
742 		dev = ipv6_dev_find(net, &local.ipv6, dev);
743 		if (!dev) {
744 			err = -ENODEV;
745 			goto err;
746 		}
747 		udp_conf.family = AF_INET6;
748 		udp_conf.use_udp6_tx_checksums = true;
749 		udp_conf.use_udp6_rx_checksums = true;
750 		if (rmcast)
751 			udp_conf.local_ip6 = in6addr_any;
752 		else
753 			udp_conf.local_ip6 = local.ipv6;
754 		ub->ifindex = dev->ifindex;
755 		b->mtu = 1280;
756 #endif
757 	} else {
758 		err = -EAFNOSUPPORT;
759 		goto err;
760 	}
761 	udp_conf.local_udp_port = local.port;
762 	err = udp_sock_create(net, &udp_conf, &ub->ubsock);
763 	if (err)
764 		goto err;
765 	tuncfg.sk_user_data = ub;
766 	tuncfg.encap_type = 1;
767 	tuncfg.encap_rcv = tipc_udp_recv;
768 	tuncfg.encap_destroy = NULL;
769 	setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
770 
771 	err = dst_cache_init(&ub->rcast.dst_cache, GFP_ATOMIC);
772 	if (err)
773 		goto free;
774 
775 	/**
776 	 * The bcast media address port is used for all peers and the ip
777 	 * is used if it's a multicast address.
778 	 */
779 	memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
780 	if (rmcast)
781 		err = enable_mcast(ub, &remote);
782 	else
783 		err = tipc_udp_rcast_add(b, &remote);
784 	if (err)
785 		goto free;
786 
787 	return 0;
788 
789 free:
790 	dst_cache_destroy(&ub->rcast.dst_cache);
791 	udp_tunnel_sock_release(ub->ubsock);
792 err:
793 	kfree(ub);
794 	return err;
795 }
796 
797 /* cleanup_bearer - break the socket/bearer association */
cleanup_bearer(struct work_struct * work)798 static void cleanup_bearer(struct work_struct *work)
799 {
800 	struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
801 	struct udp_replicast *rcast, *tmp;
802 
803 	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
804 		dst_cache_destroy(&rcast->dst_cache);
805 		list_del_rcu(&rcast->list);
806 		kfree_rcu(rcast, rcu);
807 	}
808 
809 	atomic_dec(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
810 	dst_cache_destroy(&ub->rcast.dst_cache);
811 	udp_tunnel_sock_release(ub->ubsock);
812 	synchronize_net();
813 	kfree(ub);
814 }
815 
816 /* tipc_udp_disable - detach bearer from socket */
tipc_udp_disable(struct tipc_bearer * b)817 static void tipc_udp_disable(struct tipc_bearer *b)
818 {
819 	struct udp_bearer *ub;
820 
821 	ub = rtnl_dereference(b->media_ptr);
822 	if (!ub) {
823 		pr_err("UDP bearer instance not found\n");
824 		return;
825 	}
826 	sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
827 	RCU_INIT_POINTER(ub->bearer, NULL);
828 
829 	/* sock_release need to be done outside of rtnl lock */
830 	atomic_inc(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
831 	INIT_WORK(&ub->work, cleanup_bearer);
832 	schedule_work(&ub->work);
833 }
834 
835 struct tipc_media udp_media_info = {
836 	.send_msg	= tipc_udp_send_msg,
837 	.enable_media	= tipc_udp_enable,
838 	.disable_media	= tipc_udp_disable,
839 	.addr2str	= tipc_udp_addr2str,
840 	.addr2msg	= tipc_udp_addr2msg,
841 	.msg2addr	= tipc_udp_msg2addr,
842 	.priority	= TIPC_DEF_LINK_PRI,
843 	.tolerance	= TIPC_DEF_LINK_TOL,
844 	.min_win	= TIPC_DEF_LINK_WIN,
845 	.max_win	= TIPC_DEF_LINK_WIN,
846 	.mtu		= TIPC_DEF_LINK_UDP_MTU,
847 	.type_id	= TIPC_MEDIA_TYPE_UDP,
848 	.hwaddr_len	= 0,
849 	.name		= "udp"
850 };
851