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/addrconf.h>
48 #include <linux/tipc_netlink.h>
49 #include "core.h"
50 #include "bearer.h"
51 #include "netlink.h"
52 #include "msg.h"
53
54 /* IANA assigned UDP port */
55 #define UDP_PORT_DEFAULT 6118
56
57 #define UDP_MIN_HEADROOM 48
58
59 /**
60 * struct udp_media_addr - IP/UDP addressing information
61 *
62 * This is the bearer level originating address used in neighbor discovery
63 * messages, and all fields should be in network byte order
64 */
65 struct udp_media_addr {
66 __be16 proto;
67 __be16 port;
68 union {
69 struct in_addr ipv4;
70 struct in6_addr ipv6;
71 };
72 };
73
74 /* struct udp_replicast - container for UDP remote addresses */
75 struct udp_replicast {
76 struct udp_media_addr addr;
77 struct rcu_head rcu;
78 struct list_head list;
79 };
80
81 /**
82 * struct udp_bearer - ip/udp bearer data structure
83 * @bearer: associated generic tipc bearer
84 * @ubsock: bearer associated socket
85 * @ifindex: local address scope
86 * @work: used to schedule deferred work on a bearer
87 */
88 struct udp_bearer {
89 struct tipc_bearer __rcu *bearer;
90 struct socket *ubsock;
91 u32 ifindex;
92 struct work_struct work;
93 struct udp_replicast rcast;
94 };
95
tipc_udp_is_mcast_addr(struct udp_media_addr * addr)96 static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
97 {
98 if (ntohs(addr->proto) == ETH_P_IP)
99 return ipv4_is_multicast(addr->ipv4.s_addr);
100 #if IS_ENABLED(CONFIG_IPV6)
101 else
102 return ipv6_addr_is_multicast(&addr->ipv6);
103 #endif
104 return 0;
105 }
106
107 /* 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)108 static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
109 struct udp_media_addr *ua)
110 {
111 memset(addr, 0, sizeof(struct tipc_media_addr));
112 addr->media_id = TIPC_MEDIA_TYPE_UDP;
113 memcpy(addr->value, ua, sizeof(struct udp_media_addr));
114
115 if (tipc_udp_is_mcast_addr(ua))
116 addr->broadcast = TIPC_BROADCAST_SUPPORT;
117 }
118
119 /* tipc_udp_addr2str - convert ip/udp address to string */
tipc_udp_addr2str(struct tipc_media_addr * a,char * buf,int size)120 static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
121 {
122 struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
123
124 if (ntohs(ua->proto) == ETH_P_IP)
125 snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
126 else if (ntohs(ua->proto) == ETH_P_IPV6)
127 snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
128 else
129 pr_err("Invalid UDP media address\n");
130 return 0;
131 }
132
133 /* 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)134 static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
135 char *msg)
136 {
137 struct udp_media_addr *ua;
138
139 ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
140 if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
141 return -EINVAL;
142 tipc_udp_media_addr_set(a, ua);
143 return 0;
144 }
145
146 /* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
tipc_udp_addr2msg(char * msg,struct tipc_media_addr * a)147 static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
148 {
149 memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
150 msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
151 memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
152 sizeof(struct udp_media_addr));
153 return 0;
154 }
155
156 /* 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)157 static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
158 struct udp_bearer *ub, struct udp_media_addr *src,
159 struct udp_media_addr *dst)
160 {
161 int ttl, err = 0;
162 struct rtable *rt;
163
164 if (dst->proto == htons(ETH_P_IP)) {
165 struct flowi4 fl = {
166 .daddr = dst->ipv4.s_addr,
167 .saddr = src->ipv4.s_addr,
168 .flowi4_mark = skb->mark,
169 .flowi4_proto = IPPROTO_UDP
170 };
171 rt = ip_route_output_key(net, &fl);
172 if (IS_ERR(rt)) {
173 err = PTR_ERR(rt);
174 goto tx_error;
175 }
176
177 ttl = ip4_dst_hoplimit(&rt->dst);
178 udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
179 dst->ipv4.s_addr, 0, ttl, 0, src->port,
180 dst->port, false, true);
181 #if IS_ENABLED(CONFIG_IPV6)
182 } else {
183 struct dst_entry *ndst;
184 struct flowi6 fl6 = {
185 .flowi6_oif = ub->ifindex,
186 .daddr = dst->ipv6,
187 .saddr = src->ipv6,
188 .flowi6_proto = IPPROTO_UDP
189 };
190 err = ipv6_stub->ipv6_dst_lookup(net, ub->ubsock->sk, &ndst,
191 &fl6);
192 if (err)
193 goto tx_error;
194 ttl = ip6_dst_hoplimit(ndst);
195 err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
196 &src->ipv6, &dst->ipv6, 0, ttl, 0,
197 src->port, dst->port, false);
198 #endif
199 }
200 return err;
201
202 tx_error:
203 kfree_skb(skb);
204 return err;
205 }
206
tipc_udp_send_msg(struct net * net,struct sk_buff * skb,struct tipc_bearer * b,struct tipc_media_addr * addr)207 static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
208 struct tipc_bearer *b,
209 struct tipc_media_addr *addr)
210 {
211 struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
212 struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
213 struct udp_replicast *rcast;
214 struct udp_bearer *ub;
215 int err = 0;
216
217 if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
218 err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
219 if (err)
220 goto out;
221 }
222
223 skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
224 ub = rcu_dereference_rtnl(b->media_ptr);
225 if (!ub) {
226 err = -ENODEV;
227 goto out;
228 }
229
230 if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
231 return tipc_udp_xmit(net, skb, ub, src, dst);
232
233 /* Replicast, send an skb to each configured IP address */
234 list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
235 struct sk_buff *_skb;
236
237 _skb = pskb_copy(skb, GFP_ATOMIC);
238 if (!_skb) {
239 err = -ENOMEM;
240 goto out;
241 }
242
243 err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr);
244 if (err)
245 goto out;
246 }
247 err = 0;
248 out:
249 kfree_skb(skb);
250 return err;
251 }
252
tipc_udp_is_known_peer(struct tipc_bearer * b,struct udp_media_addr * addr)253 static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
254 struct udp_media_addr *addr)
255 {
256 struct udp_replicast *rcast, *tmp;
257 struct udp_bearer *ub;
258
259 ub = rcu_dereference_rtnl(b->media_ptr);
260 if (!ub) {
261 pr_err_ratelimited("UDP bearer instance not found\n");
262 return false;
263 }
264
265 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
266 if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
267 return true;
268 }
269
270 return false;
271 }
272
tipc_udp_rcast_add(struct tipc_bearer * b,struct udp_media_addr * addr)273 static int tipc_udp_rcast_add(struct tipc_bearer *b,
274 struct udp_media_addr *addr)
275 {
276 struct udp_replicast *rcast;
277 struct udp_bearer *ub;
278
279 ub = rcu_dereference_rtnl(b->media_ptr);
280 if (!ub)
281 return -ENODEV;
282
283 rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
284 if (!rcast)
285 return -ENOMEM;
286
287 memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
288
289 if (ntohs(addr->proto) == ETH_P_IP)
290 pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
291 #if IS_ENABLED(CONFIG_IPV6)
292 else if (ntohs(addr->proto) == ETH_P_IPV6)
293 pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
294 #endif
295 b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
296 list_add_rcu(&rcast->list, &ub->rcast.list);
297 return 0;
298 }
299
tipc_udp_rcast_disc(struct tipc_bearer * b,struct sk_buff * skb)300 static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
301 {
302 struct udp_media_addr src = {0};
303 struct udp_media_addr *dst;
304
305 dst = (struct udp_media_addr *)&b->bcast_addr.value;
306 if (tipc_udp_is_mcast_addr(dst))
307 return 0;
308
309 src.port = udp_hdr(skb)->source;
310
311 if (ip_hdr(skb)->version == 4) {
312 struct iphdr *iphdr = ip_hdr(skb);
313
314 src.proto = htons(ETH_P_IP);
315 src.ipv4.s_addr = iphdr->saddr;
316 if (ipv4_is_multicast(iphdr->daddr))
317 return 0;
318 #if IS_ENABLED(CONFIG_IPV6)
319 } else if (ip_hdr(skb)->version == 6) {
320 struct ipv6hdr *iphdr = ipv6_hdr(skb);
321
322 src.proto = htons(ETH_P_IPV6);
323 src.ipv6 = iphdr->saddr;
324 if (ipv6_addr_is_multicast(&iphdr->daddr))
325 return 0;
326 #endif
327 } else {
328 return 0;
329 }
330
331 if (likely(tipc_udp_is_known_peer(b, &src)))
332 return 0;
333
334 return tipc_udp_rcast_add(b, &src);
335 }
336
337 /* tipc_udp_recv - read data from bearer socket */
tipc_udp_recv(struct sock * sk,struct sk_buff * skb)338 static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
339 {
340 struct udp_bearer *ub;
341 struct tipc_bearer *b;
342 struct tipc_msg *hdr;
343 int err;
344
345 ub = rcu_dereference_sk_user_data(sk);
346 if (!ub) {
347 pr_err_ratelimited("Failed to get UDP bearer reference");
348 goto out;
349 }
350 skb_pull(skb, sizeof(struct udphdr));
351 hdr = buf_msg(skb);
352
353 rcu_read_lock();
354 b = rcu_dereference_rtnl(ub->bearer);
355 if (!b)
356 goto rcu_out;
357
358 if (b && test_bit(0, &b->up)) {
359 tipc_rcv(sock_net(sk), skb, b);
360 rcu_read_unlock();
361 return 0;
362 }
363
364 if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
365 err = tipc_udp_rcast_disc(b, skb);
366 if (err)
367 goto rcu_out;
368 }
369
370 rcu_out:
371 rcu_read_unlock();
372 out:
373 kfree_skb(skb);
374 return 0;
375 }
376
enable_mcast(struct udp_bearer * ub,struct udp_media_addr * remote)377 static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
378 {
379 int err = 0;
380 struct ip_mreqn mreqn;
381 struct sock *sk = ub->ubsock->sk;
382
383 if (ntohs(remote->proto) == ETH_P_IP) {
384 mreqn.imr_multiaddr = remote->ipv4;
385 mreqn.imr_ifindex = ub->ifindex;
386 err = ip_mc_join_group(sk, &mreqn);
387 #if IS_ENABLED(CONFIG_IPV6)
388 } else {
389 err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
390 &remote->ipv6);
391 #endif
392 }
393 return err;
394 }
395
__tipc_nl_add_udp_addr(struct sk_buff * skb,struct udp_media_addr * addr,int nla_t)396 static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
397 struct udp_media_addr *addr, int nla_t)
398 {
399 if (ntohs(addr->proto) == ETH_P_IP) {
400 struct sockaddr_in ip4;
401
402 memset(&ip4, 0, sizeof(ip4));
403 ip4.sin_family = AF_INET;
404 ip4.sin_port = addr->port;
405 ip4.sin_addr.s_addr = addr->ipv4.s_addr;
406 if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
407 return -EMSGSIZE;
408
409 #if IS_ENABLED(CONFIG_IPV6)
410 } else if (ntohs(addr->proto) == ETH_P_IPV6) {
411 struct sockaddr_in6 ip6;
412
413 memset(&ip6, 0, sizeof(ip6));
414 ip6.sin6_family = AF_INET6;
415 ip6.sin6_port = addr->port;
416 memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
417 if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
418 return -EMSGSIZE;
419 #endif
420 }
421
422 return 0;
423 }
424
tipc_udp_nl_dump_remoteip(struct sk_buff * skb,struct netlink_callback * cb)425 int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
426 {
427 u32 bid = cb->args[0];
428 u32 skip_cnt = cb->args[1];
429 u32 portid = NETLINK_CB(cb->skb).portid;
430 struct udp_replicast *rcast, *tmp;
431 struct tipc_bearer *b;
432 struct udp_bearer *ub;
433 void *hdr;
434 int err;
435 int i;
436
437 if (!bid && !skip_cnt) {
438 struct net *net = sock_net(skb->sk);
439 struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
440 struct nlattr **attrs;
441 char *bname;
442
443 err = tipc_nlmsg_parse(cb->nlh, &attrs);
444 if (err)
445 return err;
446
447 if (!attrs[TIPC_NLA_BEARER])
448 return -EINVAL;
449
450 err = nla_parse_nested(battrs, TIPC_NLA_BEARER_MAX,
451 attrs[TIPC_NLA_BEARER],
452 tipc_nl_bearer_policy, NULL);
453 if (err)
454 return err;
455
456 if (!battrs[TIPC_NLA_BEARER_NAME])
457 return -EINVAL;
458
459 bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
460
461 rtnl_lock();
462 b = tipc_bearer_find(net, bname);
463 if (!b) {
464 rtnl_unlock();
465 return -EINVAL;
466 }
467 bid = b->identity;
468 } else {
469 struct net *net = sock_net(skb->sk);
470 struct tipc_net *tn = net_generic(net, tipc_net_id);
471
472 rtnl_lock();
473 b = rtnl_dereference(tn->bearer_list[bid]);
474 if (!b) {
475 rtnl_unlock();
476 return -EINVAL;
477 }
478 }
479
480 ub = rcu_dereference_rtnl(b->media_ptr);
481 if (!ub) {
482 rtnl_unlock();
483 return -EINVAL;
484 }
485
486 i = 0;
487 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
488 if (i < skip_cnt)
489 goto count;
490
491 hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
492 &tipc_genl_family, NLM_F_MULTI,
493 TIPC_NL_BEARER_GET);
494 if (!hdr)
495 goto done;
496
497 err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
498 TIPC_NLA_UDP_REMOTE);
499 if (err) {
500 genlmsg_cancel(skb, hdr);
501 goto done;
502 }
503 genlmsg_end(skb, hdr);
504 count:
505 i++;
506 }
507 done:
508 rtnl_unlock();
509 cb->args[0] = bid;
510 cb->args[1] = i;
511
512 return skb->len;
513 }
514
tipc_udp_nl_add_bearer_data(struct tipc_nl_msg * msg,struct tipc_bearer * b)515 int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
516 {
517 struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
518 struct udp_media_addr *dst;
519 struct udp_bearer *ub;
520 struct nlattr *nest;
521
522 ub = rcu_dereference_rtnl(b->media_ptr);
523 if (!ub)
524 return -ENODEV;
525
526 nest = nla_nest_start(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
527 if (!nest)
528 goto msg_full;
529
530 if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
531 goto msg_full;
532
533 dst = (struct udp_media_addr *)&b->bcast_addr.value;
534 if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
535 goto msg_full;
536
537 if (!list_empty(&ub->rcast.list)) {
538 if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
539 goto msg_full;
540 }
541
542 nla_nest_end(msg->skb, nest);
543 return 0;
544 msg_full:
545 nla_nest_cancel(msg->skb, nest);
546 return -EMSGSIZE;
547 }
548
549 /**
550 * tipc_parse_udp_addr - build udp media address from netlink data
551 * @nlattr: netlink attribute containing sockaddr storage aligned address
552 * @addr: tipc media address to fill with address, port and protocol type
553 * @scope_id: IPv6 scope id pointer, not NULL indicates it's required
554 */
555
tipc_parse_udp_addr(struct nlattr * nla,struct udp_media_addr * addr,u32 * scope_id)556 static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
557 u32 *scope_id)
558 {
559 struct sockaddr_storage sa;
560
561 nla_memcpy(&sa, nla, sizeof(sa));
562 if (sa.ss_family == AF_INET) {
563 struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
564
565 addr->proto = htons(ETH_P_IP);
566 addr->port = ip4->sin_port;
567 addr->ipv4.s_addr = ip4->sin_addr.s_addr;
568 return 0;
569
570 #if IS_ENABLED(CONFIG_IPV6)
571 } else if (sa.ss_family == AF_INET6) {
572 struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
573
574 addr->proto = htons(ETH_P_IPV6);
575 addr->port = ip6->sin6_port;
576 memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
577
578 /* Scope ID is only interesting for local addresses */
579 if (scope_id) {
580 int atype;
581
582 atype = ipv6_addr_type(&ip6->sin6_addr);
583 if (__ipv6_addr_needs_scope_id(atype) &&
584 !ip6->sin6_scope_id) {
585 return -EINVAL;
586 }
587
588 *scope_id = ip6->sin6_scope_id ? : 0;
589 }
590
591 return 0;
592 #endif
593 }
594 return -EADDRNOTAVAIL;
595 }
596
tipc_udp_nl_bearer_add(struct tipc_bearer * b,struct nlattr * attr)597 int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
598 {
599 int err;
600 struct udp_media_addr addr = {0};
601 struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
602 struct udp_media_addr *dst;
603
604 if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX, attr,
605 tipc_nl_udp_policy, NULL))
606 return -EINVAL;
607
608 if (!opts[TIPC_NLA_UDP_REMOTE])
609 return -EINVAL;
610
611 err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
612 if (err)
613 return err;
614
615 dst = (struct udp_media_addr *)&b->bcast_addr.value;
616 if (tipc_udp_is_mcast_addr(dst)) {
617 pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
618 return -EINVAL;
619 }
620
621 if (tipc_udp_is_known_peer(b, &addr))
622 return 0;
623
624 return tipc_udp_rcast_add(b, &addr);
625 }
626
627 /**
628 * tipc_udp_enable - callback to create a new udp bearer instance
629 * @net: network namespace
630 * @b: pointer to generic tipc_bearer
631 * @attrs: netlink bearer configuration
632 *
633 * validate the bearer parameters and initialize the udp bearer
634 * rtnl_lock should be held
635 */
tipc_udp_enable(struct net * net,struct tipc_bearer * b,struct nlattr * attrs[])636 static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
637 struct nlattr *attrs[])
638 {
639 int err = -EINVAL;
640 struct udp_bearer *ub;
641 struct udp_media_addr remote = {0};
642 struct udp_media_addr local = {0};
643 struct udp_port_cfg udp_conf = {0};
644 struct udp_tunnel_sock_cfg tuncfg = {NULL};
645 struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
646
647 ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
648 if (!ub)
649 return -ENOMEM;
650
651 INIT_LIST_HEAD(&ub->rcast.list);
652
653 if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
654 goto err;
655
656 if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX,
657 attrs[TIPC_NLA_BEARER_UDP_OPTS],
658 tipc_nl_udp_policy, NULL))
659 goto err;
660
661 if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
662 pr_err("Invalid UDP bearer configuration");
663 err = -EINVAL;
664 goto err;
665 }
666
667 err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
668 &ub->ifindex);
669 if (err)
670 goto err;
671
672 err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
673 if (err)
674 goto err;
675
676 if (remote.proto != local.proto) {
677 err = -EINVAL;
678 goto err;
679 }
680
681 b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
682 b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
683 rcu_assign_pointer(b->media_ptr, ub);
684 rcu_assign_pointer(ub->bearer, b);
685 tipc_udp_media_addr_set(&b->addr, &local);
686 if (local.proto == htons(ETH_P_IP)) {
687 struct net_device *dev;
688
689 dev = __ip_dev_find(net, local.ipv4.s_addr, false);
690 if (!dev) {
691 err = -ENODEV;
692 goto err;
693 }
694 udp_conf.family = AF_INET;
695 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
696 udp_conf.use_udp_checksums = false;
697 ub->ifindex = dev->ifindex;
698 if (tipc_mtu_bad(dev, sizeof(struct iphdr) +
699 sizeof(struct udphdr))) {
700 err = -EINVAL;
701 goto err;
702 }
703 b->mtu = dev->mtu - sizeof(struct iphdr)
704 - sizeof(struct udphdr);
705 #if IS_ENABLED(CONFIG_IPV6)
706 } else if (local.proto == htons(ETH_P_IPV6)) {
707 udp_conf.family = AF_INET6;
708 udp_conf.use_udp6_tx_checksums = true;
709 udp_conf.use_udp6_rx_checksums = true;
710 udp_conf.local_ip6 = in6addr_any;
711 b->mtu = 1280;
712 #endif
713 } else {
714 err = -EAFNOSUPPORT;
715 goto err;
716 }
717 udp_conf.local_udp_port = local.port;
718 err = udp_sock_create(net, &udp_conf, &ub->ubsock);
719 if (err)
720 goto err;
721 tuncfg.sk_user_data = ub;
722 tuncfg.encap_type = 1;
723 tuncfg.encap_rcv = tipc_udp_recv;
724 tuncfg.encap_destroy = NULL;
725 setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
726
727 /**
728 * The bcast media address port is used for all peers and the ip
729 * is used if it's a multicast address.
730 */
731 memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
732 if (tipc_udp_is_mcast_addr(&remote))
733 err = enable_mcast(ub, &remote);
734 else
735 err = tipc_udp_rcast_add(b, &remote);
736 if (err)
737 goto err;
738
739 return 0;
740 err:
741 if (ub->ubsock)
742 udp_tunnel_sock_release(ub->ubsock);
743 kfree(ub);
744 return err;
745 }
746
747 /* cleanup_bearer - break the socket/bearer association */
cleanup_bearer(struct work_struct * work)748 static void cleanup_bearer(struct work_struct *work)
749 {
750 struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
751 struct udp_replicast *rcast, *tmp;
752
753 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
754 list_del_rcu(&rcast->list);
755 kfree_rcu(rcast, rcu);
756 }
757
758 if (ub->ubsock)
759 udp_tunnel_sock_release(ub->ubsock);
760 synchronize_net();
761 kfree(ub);
762 }
763
764 /* tipc_udp_disable - detach bearer from socket */
tipc_udp_disable(struct tipc_bearer * b)765 static void tipc_udp_disable(struct tipc_bearer *b)
766 {
767 struct udp_bearer *ub;
768
769 ub = rcu_dereference_rtnl(b->media_ptr);
770 if (!ub) {
771 pr_err("UDP bearer instance not found\n");
772 return;
773 }
774 if (ub->ubsock)
775 sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
776 RCU_INIT_POINTER(ub->bearer, NULL);
777
778 /* sock_release need to be done outside of rtnl lock */
779 INIT_WORK(&ub->work, cleanup_bearer);
780 schedule_work(&ub->work);
781 }
782
783 struct tipc_media udp_media_info = {
784 .send_msg = tipc_udp_send_msg,
785 .enable_media = tipc_udp_enable,
786 .disable_media = tipc_udp_disable,
787 .addr2str = tipc_udp_addr2str,
788 .addr2msg = tipc_udp_addr2msg,
789 .msg2addr = tipc_udp_msg2addr,
790 .priority = TIPC_DEF_LINK_PRI,
791 .tolerance = TIPC_DEF_LINK_TOL,
792 .window = TIPC_DEF_LINK_WIN,
793 .type_id = TIPC_MEDIA_TYPE_UDP,
794 .hwaddr_len = 0,
795 .name = "udp"
796 };
797