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 * @proto: Ethernet protocol in use
69 * @port: port being used
70 * @ipv4: IPv4 address of neighbor
71 * @ipv6: IPv6 address of neighbor
72 */
73struct udp_media_addr {
74 __be16 proto;
75 __be16 port;
76 union {
77 struct in_addr ipv4;
78 struct in6_addr ipv6;
79 };
80};
81
82/* struct udp_replicast - container for UDP remote addresses */
83struct udp_replicast {
84 struct udp_media_addr addr;
85 struct dst_cache dst_cache;
86 struct rcu_head rcu;
87 struct list_head list;
88};
89
90/**
91 * struct udp_bearer - ip/udp bearer data structure
92 * @bearer: associated generic tipc bearer
93 * @ubsock: bearer associated socket
94 * @ifindex: local address scope
95 * @work: used to schedule deferred work on a bearer
96 * @rcast: associated udp_replicast container
97 */
98struct udp_bearer {
99 struct tipc_bearer __rcu *bearer;
100 struct socket *ubsock;
101 u32 ifindex;
102 struct work_struct work;
103 struct udp_replicast rcast;
104};
105
106static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
107{
108 if (ntohs(addr->proto) == ETH_P_IP)
109 return ipv4_is_multicast(addr: addr->ipv4.s_addr);
110#if IS_ENABLED(CONFIG_IPV6)
111 else
112 return ipv6_addr_is_multicast(addr: &addr->ipv6);
113#endif
114 return 0;
115}
116
117/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
118static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
119 struct udp_media_addr *ua)
120{
121 memset(addr, 0, sizeof(struct tipc_media_addr));
122 addr->media_id = TIPC_MEDIA_TYPE_UDP;
123 memcpy(addr->value, ua, sizeof(struct udp_media_addr));
124
125 if (tipc_udp_is_mcast_addr(addr: ua))
126 addr->broadcast = TIPC_BROADCAST_SUPPORT;
127}
128
129/* tipc_udp_addr2str - convert ip/udp address to string */
130static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
131{
132 struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
133
134 if (ntohs(ua->proto) == ETH_P_IP)
135 snprintf(buf, size, fmt: "%pI4:%u", &ua->ipv4, ntohs(ua->port));
136 else if (ntohs(ua->proto) == ETH_P_IPV6)
137 snprintf(buf, size, fmt: "%pI6:%u", &ua->ipv6, ntohs(ua->port));
138 else
139 pr_err("Invalid UDP media address\n");
140 return 0;
141}
142
143/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
144static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
145 char *msg)
146{
147 struct udp_media_addr *ua;
148
149 ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
150 if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
151 return -EINVAL;
152 tipc_udp_media_addr_set(addr: a, ua);
153 return 0;
154}
155
156/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
157static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
158{
159 memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
160 msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
161 memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
162 sizeof(struct udp_media_addr));
163 return 0;
164}
165
166/* tipc_send_msg - enqueue a send request */
167static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
168 struct udp_bearer *ub, struct udp_media_addr *src,
169 struct udp_media_addr *dst, struct dst_cache *cache)
170{
171 struct dst_entry *ndst;
172 int ttl, err = 0;
173
174 local_bh_disable();
175 ndst = dst_cache_get(dst_cache: cache);
176 if (dst->proto == htons(ETH_P_IP)) {
177 struct rtable *rt = (struct rtable *)ndst;
178
179 if (!rt) {
180 struct flowi4 fl = {
181 .daddr = dst->ipv4.s_addr,
182 .saddr = src->ipv4.s_addr,
183 .flowi4_mark = skb->mark,
184 .flowi4_proto = IPPROTO_UDP
185 };
186 rt = ip_route_output_key(net, flp: &fl);
187 if (IS_ERR(ptr: rt)) {
188 err = PTR_ERR(ptr: rt);
189 goto tx_error;
190 }
191 dst_cache_set_ip4(dst_cache: cache, dst: &rt->dst, saddr: fl.saddr);
192 }
193
194 ttl = ip4_dst_hoplimit(dst: &rt->dst);
195 udp_tunnel_xmit_skb(rt, sk: ub->ubsock->sk, skb, src: src->ipv4.s_addr,
196 dst: dst->ipv4.s_addr, tos: 0, ttl, df: 0, src_port: src->port,
197 dst_port: dst->port, xnet: false, nocheck: true);
198#if IS_ENABLED(CONFIG_IPV6)
199 } else {
200 if (!ndst) {
201 struct flowi6 fl6 = {
202 .flowi6_oif = ub->ifindex,
203 .daddr = dst->ipv6,
204 .saddr = src->ipv6,
205 .flowi6_proto = IPPROTO_UDP
206 };
207 ndst = ipv6_stub->ipv6_dst_lookup_flow(net,
208 ub->ubsock->sk,
209 &fl6, NULL);
210 if (IS_ERR(ptr: ndst)) {
211 err = PTR_ERR(ptr: ndst);
212 goto tx_error;
213 }
214 dst_cache_set_ip6(dst_cache: cache, dst: ndst, saddr: &fl6.saddr);
215 }
216 ttl = ip6_dst_hoplimit(dst: ndst);
217 err = udp_tunnel6_xmit_skb(dst: ndst, sk: ub->ubsock->sk, skb, NULL,
218 saddr: &src->ipv6, daddr: &dst->ipv6, prio: 0, ttl, label: 0,
219 src_port: src->port, dst_port: dst->port, nocheck: false);
220#endif
221 }
222 local_bh_enable();
223 return err;
224
225tx_error:
226 local_bh_enable();
227 kfree_skb(skb);
228 return err;
229}
230
231static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
232 struct tipc_bearer *b,
233 struct tipc_media_addr *addr)
234{
235 struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
236 struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
237 struct udp_replicast *rcast;
238 struct udp_bearer *ub;
239 int err = 0;
240
241 if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
242 err = pskb_expand_head(skb, UDP_MIN_HEADROOM, ntail: 0, GFP_ATOMIC);
243 if (err)
244 goto out;
245 }
246
247 skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
248 ub = rcu_dereference(b->media_ptr);
249 if (!ub) {
250 err = -ENODEV;
251 goto out;
252 }
253
254 if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
255 return tipc_udp_xmit(net, skb, ub, src, dst,
256 cache: &ub->rcast.dst_cache);
257
258 /* Replicast, send an skb to each configured IP address */
259 list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
260 struct sk_buff *_skb;
261
262 _skb = pskb_copy(skb, GFP_ATOMIC);
263 if (!_skb) {
264 err = -ENOMEM;
265 goto out;
266 }
267
268 err = tipc_udp_xmit(net, skb: _skb, ub, src, dst: &rcast->addr,
269 cache: &rcast->dst_cache);
270 if (err)
271 goto out;
272 }
273 err = 0;
274out:
275 kfree_skb(skb);
276 return err;
277}
278
279static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
280 struct udp_media_addr *addr)
281{
282 struct udp_replicast *rcast, *tmp;
283 struct udp_bearer *ub;
284
285 ub = rcu_dereference_rtnl(b->media_ptr);
286 if (!ub) {
287 pr_err_ratelimited("UDP bearer instance not found\n");
288 return false;
289 }
290
291 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
292 if (!memcmp(p: &rcast->addr, q: addr, size: sizeof(struct udp_media_addr)))
293 return true;
294 }
295
296 return false;
297}
298
299static int tipc_udp_rcast_add(struct tipc_bearer *b,
300 struct udp_media_addr *addr)
301{
302 struct udp_replicast *rcast;
303 struct udp_bearer *ub;
304
305 ub = rcu_dereference_rtnl(b->media_ptr);
306 if (!ub)
307 return -ENODEV;
308
309 rcast = kmalloc(size: sizeof(*rcast), GFP_ATOMIC);
310 if (!rcast)
311 return -ENOMEM;
312
313 if (dst_cache_init(dst_cache: &rcast->dst_cache, GFP_ATOMIC)) {
314 kfree(objp: rcast);
315 return -ENOMEM;
316 }
317
318 memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
319
320 if (ntohs(addr->proto) == ETH_P_IP)
321 pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
322#if IS_ENABLED(CONFIG_IPV6)
323 else if (ntohs(addr->proto) == ETH_P_IPV6)
324 pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
325#endif
326 b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
327 list_add_rcu(new: &rcast->list, head: &ub->rcast.list);
328 return 0;
329}
330
331static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
332{
333 struct udp_media_addr src = {0};
334 struct udp_media_addr *dst;
335
336 dst = (struct udp_media_addr *)&b->bcast_addr.value;
337 if (tipc_udp_is_mcast_addr(addr: dst))
338 return 0;
339
340 src.port = udp_hdr(skb)->source;
341
342 if (ip_hdr(skb)->version == 4) {
343 struct iphdr *iphdr = ip_hdr(skb);
344
345 src.proto = htons(ETH_P_IP);
346 src.ipv4.s_addr = iphdr->saddr;
347 if (ipv4_is_multicast(addr: iphdr->daddr))
348 return 0;
349#if IS_ENABLED(CONFIG_IPV6)
350 } else if (ip_hdr(skb)->version == 6) {
351 struct ipv6hdr *iphdr = ipv6_hdr(skb);
352
353 src.proto = htons(ETH_P_IPV6);
354 src.ipv6 = iphdr->saddr;
355 if (ipv6_addr_is_multicast(addr: &iphdr->daddr))
356 return 0;
357#endif
358 } else {
359 return 0;
360 }
361
362 if (likely(tipc_udp_is_known_peer(b, &src)))
363 return 0;
364
365 return tipc_udp_rcast_add(b, addr: &src);
366}
367
368/* tipc_udp_recv - read data from bearer socket */
369static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
370{
371 struct udp_bearer *ub;
372 struct tipc_bearer *b;
373 struct tipc_msg *hdr;
374 int err;
375
376 ub = rcu_dereference_sk_user_data(sk);
377 if (!ub) {
378 pr_err_ratelimited("Failed to get UDP bearer reference");
379 goto out;
380 }
381 skb_pull(skb, len: sizeof(struct udphdr));
382 hdr = buf_msg(skb);
383
384 b = rcu_dereference(ub->bearer);
385 if (!b)
386 goto out;
387
388 if (b && test_bit(0, &b->up)) {
389 TIPC_SKB_CB(skb)->flags = 0;
390 tipc_rcv(net: sock_net(sk), skb, b);
391 return 0;
392 }
393
394 if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
395 err = tipc_udp_rcast_disc(b, skb);
396 if (err)
397 goto out;
398 }
399
400out:
401 kfree_skb(skb);
402 return 0;
403}
404
405static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
406{
407 int err = 0;
408 struct ip_mreqn mreqn;
409 struct sock *sk = ub->ubsock->sk;
410
411 if (ntohs(remote->proto) == ETH_P_IP) {
412 mreqn.imr_multiaddr = remote->ipv4;
413 mreqn.imr_ifindex = ub->ifindex;
414 err = ip_mc_join_group(sk, imr: &mreqn);
415#if IS_ENABLED(CONFIG_IPV6)
416 } else {
417 lock_sock(sk);
418 err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
419 &remote->ipv6);
420 release_sock(sk);
421#endif
422 }
423 return err;
424}
425
426static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
427 struct udp_media_addr *addr, int nla_t)
428{
429 if (ntohs(addr->proto) == ETH_P_IP) {
430 struct sockaddr_in ip4;
431
432 memset(&ip4, 0, sizeof(ip4));
433 ip4.sin_family = AF_INET;
434 ip4.sin_port = addr->port;
435 ip4.sin_addr.s_addr = addr->ipv4.s_addr;
436 if (nla_put(skb, attrtype: nla_t, attrlen: sizeof(ip4), data: &ip4))
437 return -EMSGSIZE;
438
439#if IS_ENABLED(CONFIG_IPV6)
440 } else if (ntohs(addr->proto) == ETH_P_IPV6) {
441 struct sockaddr_in6 ip6;
442
443 memset(&ip6, 0, sizeof(ip6));
444 ip6.sin6_family = AF_INET6;
445 ip6.sin6_port = addr->port;
446 memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
447 if (nla_put(skb, attrtype: nla_t, attrlen: sizeof(ip6), data: &ip6))
448 return -EMSGSIZE;
449#endif
450 }
451
452 return 0;
453}
454
455int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
456{
457 u32 bid = cb->args[0];
458 u32 skip_cnt = cb->args[1];
459 u32 portid = NETLINK_CB(cb->skb).portid;
460 struct udp_replicast *rcast, *tmp;
461 struct tipc_bearer *b;
462 struct udp_bearer *ub;
463 void *hdr;
464 int err;
465 int i;
466
467 if (!bid && !skip_cnt) {
468 struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
469 struct net *net = sock_net(sk: skb->sk);
470 struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
471 char *bname;
472
473 if (!attrs[TIPC_NLA_BEARER])
474 return -EINVAL;
475
476 err = nla_parse_nested_deprecated(tb: battrs, maxtype: TIPC_NLA_BEARER_MAX,
477 nla: attrs[TIPC_NLA_BEARER],
478 policy: tipc_nl_bearer_policy, NULL);
479 if (err)
480 return err;
481
482 if (!battrs[TIPC_NLA_BEARER_NAME])
483 return -EINVAL;
484
485 bname = nla_data(nla: battrs[TIPC_NLA_BEARER_NAME]);
486
487 rtnl_lock();
488 b = tipc_bearer_find(net, name: bname);
489 if (!b) {
490 rtnl_unlock();
491 return -EINVAL;
492 }
493 bid = b->identity;
494 } else {
495 struct net *net = sock_net(sk: skb->sk);
496 struct tipc_net *tn = net_generic(net, id: tipc_net_id);
497
498 rtnl_lock();
499 b = rtnl_dereference(tn->bearer_list[bid]);
500 if (!b) {
501 rtnl_unlock();
502 return -EINVAL;
503 }
504 }
505
506 ub = rtnl_dereference(b->media_ptr);
507 if (!ub) {
508 rtnl_unlock();
509 return -EINVAL;
510 }
511
512 i = 0;
513 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
514 if (i < skip_cnt)
515 goto count;
516
517 hdr = genlmsg_put(skb, portid, seq: cb->nlh->nlmsg_seq,
518 family: &tipc_genl_family, NLM_F_MULTI,
519 cmd: TIPC_NL_BEARER_GET);
520 if (!hdr)
521 goto done;
522
523 err = __tipc_nl_add_udp_addr(skb, addr: &rcast->addr,
524 nla_t: TIPC_NLA_UDP_REMOTE);
525 if (err) {
526 genlmsg_cancel(skb, hdr);
527 goto done;
528 }
529 genlmsg_end(skb, hdr);
530count:
531 i++;
532 }
533done:
534 rtnl_unlock();
535 cb->args[0] = bid;
536 cb->args[1] = i;
537
538 return skb->len;
539}
540
541int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
542{
543 struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
544 struct udp_media_addr *dst;
545 struct udp_bearer *ub;
546 struct nlattr *nest;
547
548 ub = rtnl_dereference(b->media_ptr);
549 if (!ub)
550 return -ENODEV;
551
552 nest = nla_nest_start_noflag(skb: msg->skb, attrtype: TIPC_NLA_BEARER_UDP_OPTS);
553 if (!nest)
554 goto msg_full;
555
556 if (__tipc_nl_add_udp_addr(skb: msg->skb, addr: src, nla_t: TIPC_NLA_UDP_LOCAL))
557 goto msg_full;
558
559 dst = (struct udp_media_addr *)&b->bcast_addr.value;
560 if (__tipc_nl_add_udp_addr(skb: msg->skb, addr: dst, nla_t: TIPC_NLA_UDP_REMOTE))
561 goto msg_full;
562
563 if (!list_empty(head: &ub->rcast.list)) {
564 if (nla_put_flag(skb: msg->skb, attrtype: TIPC_NLA_UDP_MULTI_REMOTEIP))
565 goto msg_full;
566 }
567
568 nla_nest_end(skb: msg->skb, start: nest);
569 return 0;
570msg_full:
571 nla_nest_cancel(skb: msg->skb, start: nest);
572 return -EMSGSIZE;
573}
574
575/**
576 * tipc_parse_udp_addr - build udp media address from netlink data
577 * @nla: netlink attribute containing sockaddr storage aligned address
578 * @addr: tipc media address to fill with address, port and protocol type
579 * @scope_id: IPv6 scope id pointer, not NULL indicates it's required
580 */
581
582static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
583 u32 *scope_id)
584{
585 struct sockaddr_storage sa;
586
587 nla_memcpy(dest: &sa, src: nla, count: sizeof(sa));
588 if (sa.ss_family == AF_INET) {
589 struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
590
591 addr->proto = htons(ETH_P_IP);
592 addr->port = ip4->sin_port;
593 addr->ipv4.s_addr = ip4->sin_addr.s_addr;
594 return 0;
595
596#if IS_ENABLED(CONFIG_IPV6)
597 } else if (sa.ss_family == AF_INET6) {
598 struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
599
600 addr->proto = htons(ETH_P_IPV6);
601 addr->port = ip6->sin6_port;
602 memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
603
604 /* Scope ID is only interesting for local addresses */
605 if (scope_id) {
606 int atype;
607
608 atype = ipv6_addr_type(addr: &ip6->sin6_addr);
609 if (__ipv6_addr_needs_scope_id(type: atype) &&
610 !ip6->sin6_scope_id) {
611 return -EINVAL;
612 }
613
614 *scope_id = ip6->sin6_scope_id ? : 0;
615 }
616
617 return 0;
618#endif
619 }
620 return -EADDRNOTAVAIL;
621}
622
623int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
624{
625 int err;
626 struct udp_media_addr addr = {0};
627 struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
628 struct udp_media_addr *dst;
629
630 if (nla_parse_nested_deprecated(tb: opts, maxtype: TIPC_NLA_UDP_MAX, nla: attr, policy: tipc_nl_udp_policy, NULL))
631 return -EINVAL;
632
633 if (!opts[TIPC_NLA_UDP_REMOTE])
634 return -EINVAL;
635
636 err = tipc_parse_udp_addr(nla: opts[TIPC_NLA_UDP_REMOTE], addr: &addr, NULL);
637 if (err)
638 return err;
639
640 dst = (struct udp_media_addr *)&b->bcast_addr.value;
641 if (tipc_udp_is_mcast_addr(addr: dst)) {
642 pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
643 return -EINVAL;
644 }
645
646 if (tipc_udp_is_known_peer(b, addr: &addr))
647 return 0;
648
649 return tipc_udp_rcast_add(b, addr: &addr);
650}
651
652/**
653 * tipc_udp_enable - callback to create a new udp bearer instance
654 * @net: network namespace
655 * @b: pointer to generic tipc_bearer
656 * @attrs: netlink bearer configuration
657 *
658 * validate the bearer parameters and initialize the udp bearer
659 * rtnl_lock should be held
660 */
661static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
662 struct nlattr *attrs[])
663{
664 int err = -EINVAL;
665 struct udp_bearer *ub;
666 struct udp_media_addr remote = {0};
667 struct udp_media_addr local = {0};
668 struct udp_port_cfg udp_conf = {0};
669 struct udp_tunnel_sock_cfg tuncfg = {NULL};
670 struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
671 u8 node_id[NODE_ID_LEN] = {0,};
672 struct net_device *dev;
673 int rmcast = 0;
674
675 ub = kzalloc(size: sizeof(*ub), GFP_ATOMIC);
676 if (!ub)
677 return -ENOMEM;
678
679 INIT_LIST_HEAD(list: &ub->rcast.list);
680
681 if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
682 goto err;
683
684 if (nla_parse_nested_deprecated(tb: opts, maxtype: TIPC_NLA_UDP_MAX, nla: attrs[TIPC_NLA_BEARER_UDP_OPTS], policy: tipc_nl_udp_policy, NULL))
685 goto err;
686
687 if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
688 pr_err("Invalid UDP bearer configuration");
689 err = -EINVAL;
690 goto err;
691 }
692
693 err = tipc_parse_udp_addr(nla: opts[TIPC_NLA_UDP_LOCAL], addr: &local,
694 scope_id: &ub->ifindex);
695 if (err)
696 goto err;
697
698 err = tipc_parse_udp_addr(nla: opts[TIPC_NLA_UDP_REMOTE], addr: &remote, NULL);
699 if (err)
700 goto err;
701
702 if (remote.proto != local.proto) {
703 err = -EINVAL;
704 goto err;
705 }
706
707 /* Checking remote ip address */
708 rmcast = tipc_udp_is_mcast_addr(addr: &remote);
709
710 /* Autoconfigure own node identity if needed */
711 if (!tipc_own_id(net)) {
712 memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
713 tipc_net_init(net, node_id, addr: 0);
714 }
715 if (!tipc_own_id(net)) {
716 pr_warn("Failed to set node id, please configure manually\n");
717 err = -EINVAL;
718 goto err;
719 }
720
721 b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
722 b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
723 rcu_assign_pointer(b->media_ptr, ub);
724 rcu_assign_pointer(ub->bearer, b);
725 tipc_udp_media_addr_set(addr: &b->addr, ua: &local);
726 if (local.proto == htons(ETH_P_IP)) {
727 dev = __ip_dev_find(net, addr: local.ipv4.s_addr, devref: false);
728 if (!dev) {
729 err = -ENODEV;
730 goto err;
731 }
732 udp_conf.family = AF_INET;
733
734 /* Switch to use ANY to receive packets from group */
735 if (rmcast)
736 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
737 else
738 udp_conf.local_ip.s_addr = local.ipv4.s_addr;
739 udp_conf.use_udp_checksums = false;
740 ub->ifindex = dev->ifindex;
741 b->encap_hlen = sizeof(struct iphdr) + sizeof(struct udphdr);
742 b->mtu = b->media->mtu;
743#if IS_ENABLED(CONFIG_IPV6)
744 } else if (local.proto == htons(ETH_P_IPV6)) {
745 dev = ub->ifindex ? __dev_get_by_index(net, ifindex: ub->ifindex) : NULL;
746 dev = ipv6_dev_find(net, addr: &local.ipv6, dev);
747 if (!dev) {
748 err = -ENODEV;
749 goto err;
750 }
751 udp_conf.family = AF_INET6;
752 udp_conf.use_udp6_tx_checksums = true;
753 udp_conf.use_udp6_rx_checksums = true;
754 if (rmcast)
755 udp_conf.local_ip6 = in6addr_any;
756 else
757 udp_conf.local_ip6 = local.ipv6;
758 ub->ifindex = dev->ifindex;
759 b->encap_hlen = sizeof(struct ipv6hdr) + sizeof(struct udphdr);
760 b->mtu = 1280;
761#endif
762 } else {
763 err = -EAFNOSUPPORT;
764 goto err;
765 }
766 udp_conf.local_udp_port = local.port;
767 err = udp_sock_create(net, cfg: &udp_conf, sockp: &ub->ubsock);
768 if (err)
769 goto err;
770 tuncfg.sk_user_data = ub;
771 tuncfg.encap_type = 1;
772 tuncfg.encap_rcv = tipc_udp_recv;
773 tuncfg.encap_destroy = NULL;
774 setup_udp_tunnel_sock(net, sock: ub->ubsock, sock_cfg: &tuncfg);
775
776 err = dst_cache_init(dst_cache: &ub->rcast.dst_cache, GFP_ATOMIC);
777 if (err)
778 goto free;
779
780 /*
781 * The bcast media address port is used for all peers and the ip
782 * is used if it's a multicast address.
783 */
784 memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
785 if (rmcast)
786 err = enable_mcast(ub, remote: &remote);
787 else
788 err = tipc_udp_rcast_add(b, addr: &remote);
789 if (err)
790 goto free;
791
792 return 0;
793
794free:
795 dst_cache_destroy(dst_cache: &ub->rcast.dst_cache);
796 udp_tunnel_sock_release(sock: ub->ubsock);
797err:
798 kfree(objp: ub);
799 return err;
800}
801
802/* cleanup_bearer - break the socket/bearer association */
803static void cleanup_bearer(struct work_struct *work)
804{
805 struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
806 struct udp_replicast *rcast, *tmp;
807
808 list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
809 dst_cache_destroy(dst_cache: &rcast->dst_cache);
810 list_del_rcu(entry: &rcast->list);
811 kfree_rcu(rcast, rcu);
812 }
813
814 atomic_dec(v: &tipc_net(net: sock_net(sk: ub->ubsock->sk))->wq_count);
815 dst_cache_destroy(dst_cache: &ub->rcast.dst_cache);
816 udp_tunnel_sock_release(sock: ub->ubsock);
817 synchronize_net();
818 kfree(objp: ub);
819}
820
821/* tipc_udp_disable - detach bearer from socket */
822static void tipc_udp_disable(struct tipc_bearer *b)
823{
824 struct udp_bearer *ub;
825
826 ub = rtnl_dereference(b->media_ptr);
827 if (!ub) {
828 pr_err("UDP bearer instance not found\n");
829 return;
830 }
831 sock_set_flag(sk: ub->ubsock->sk, flag: SOCK_DEAD);
832 RCU_INIT_POINTER(ub->bearer, NULL);
833
834 /* sock_release need to be done outside of rtnl lock */
835 atomic_inc(v: &tipc_net(net: sock_net(sk: ub->ubsock->sk))->wq_count);
836 INIT_WORK(&ub->work, cleanup_bearer);
837 schedule_work(work: &ub->work);
838}
839
840struct tipc_media udp_media_info = {
841 .send_msg = tipc_udp_send_msg,
842 .enable_media = tipc_udp_enable,
843 .disable_media = tipc_udp_disable,
844 .addr2str = tipc_udp_addr2str,
845 .addr2msg = tipc_udp_addr2msg,
846 .msg2addr = tipc_udp_msg2addr,
847 .priority = TIPC_DEF_LINK_PRI,
848 .tolerance = TIPC_DEF_LINK_TOL,
849 .min_win = TIPC_DEF_LINK_WIN,
850 .max_win = TIPC_DEF_LINK_WIN,
851 .mtu = TIPC_DEF_LINK_UDP_MTU,
852 .type_id = TIPC_MEDIA_TYPE_UDP,
853 .hwaddr_len = 0,
854 .name = "udp"
855};
856

source code of linux/net/tipc/udp_media.c