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->ipv4.s_addr);
110#if IS_ENABLED(CONFIG_IPV6)
111	else
112		return ipv6_addr_is_multicast(&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(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, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
136	else if (ntohs(ua->proto) == ETH_P_IPV6)
137		snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
138	else {
139		pr_err("Invalid UDP media address\n");
140		return 1;
141	}
142
143	return 0;
144}
145
146/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
147static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
148			     char *msg)
149{
150	struct udp_media_addr *ua;
151
152	ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
153	if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
154		return -EINVAL;
155	tipc_udp_media_addr_set(a, ua);
156	return 0;
157}
158
159/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
160static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
161{
162	memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
163	msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
164	memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
165	       sizeof(struct udp_media_addr));
166	return 0;
167}
168
169/* tipc_send_msg - enqueue a send request */
170static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
171			 struct udp_bearer *ub, struct udp_media_addr *src,
172			 struct udp_media_addr *dst, struct dst_cache *cache)
173{
174	struct dst_entry *ndst;
175	int ttl, err = 0;
176
177	local_bh_disable();
178	ndst = dst_cache_get(cache);
179	if (dst->proto == htons(ETH_P_IP)) {
180		struct rtable *rt = dst_rtable(ndst);
181
182		if (!rt) {
183			struct flowi4 fl = {
184				.daddr = dst->ipv4.s_addr,
185				.saddr = src->ipv4.s_addr,
186				.flowi4_mark = skb->mark,
187				.flowi4_proto = IPPROTO_UDP
188			};
189			rt = ip_route_output_key(net, &fl);
190			if (IS_ERR(rt)) {
191				err = PTR_ERR(rt);
192				goto tx_error;
193			}
194			dst_cache_set_ip4(cache, &rt->dst, fl.saddr);
195		}
196
197		ttl = ip4_dst_hoplimit(&rt->dst);
198		udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
199				    dst->ipv4.s_addr, 0, ttl, 0, src->port,
200				    dst->port, false, true);
201#if IS_ENABLED(CONFIG_IPV6)
202	} else {
203		if (!ndst) {
204			struct flowi6 fl6 = {
205				.flowi6_oif = ub->ifindex,
206				.daddr = dst->ipv6,
207				.saddr = src->ipv6,
208				.flowi6_proto = IPPROTO_UDP
209			};
210			ndst = ipv6_stub->ipv6_dst_lookup_flow(net,
211							       ub->ubsock->sk,
212							       &fl6, NULL);
213			if (IS_ERR(ndst)) {
214				err = PTR_ERR(ndst);
215				goto tx_error;
216			}
217			dst_cache_set_ip6(cache, ndst, &fl6.saddr);
218		}
219		ttl = ip6_dst_hoplimit(ndst);
220		err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
221					   &src->ipv6, &dst->ipv6, 0, ttl, 0,
222					   src->port, dst->port, false);
223#endif
224	}
225	local_bh_enable();
226	return err;
227
228tx_error:
229	local_bh_enable();
230	kfree_skb(skb);
231	return err;
232}
233
234static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
235			     struct tipc_bearer *b,
236			     struct tipc_media_addr *addr)
237{
238	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
239	struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
240	struct udp_replicast *rcast;
241	struct udp_bearer *ub;
242	int err = 0;
 
 
243
244	if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
245		err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
246		if (err)
247			goto out;
248	}
249
250	skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
251	ub = rcu_dereference(b->media_ptr);
252	if (!ub) {
253		err = -ENODEV;
254		goto out;
255	}
256
257	if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
258		return tipc_udp_xmit(net, skb, ub, src, dst,
259				     &ub->rcast.dst_cache);
260
261	/* Replicast, send an skb to each configured IP address */
262	list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
263		struct sk_buff *_skb;
264
265		_skb = pskb_copy(skb, GFP_ATOMIC);
266		if (!_skb) {
267			err = -ENOMEM;
268			goto out;
269		}
270
271		err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr,
272				    &rcast->dst_cache);
273		if (err)
274			goto out;
275	}
276	err = 0;
277out:
278	kfree_skb(skb);
279	return err;
280}
281
282static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
283				   struct udp_media_addr *addr)
284{
285	struct udp_replicast *rcast, *tmp;
286	struct udp_bearer *ub;
287
288	ub = rcu_dereference_rtnl(b->media_ptr);
289	if (!ub) {
290		pr_err_ratelimited("UDP bearer instance not found\n");
291		return false;
292	}
293
294	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
295		if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
296			return true;
297	}
298
299	return false;
300}
301
302static int tipc_udp_rcast_add(struct tipc_bearer *b,
303			      struct udp_media_addr *addr)
304{
305	struct udp_replicast *rcast;
306	struct udp_bearer *ub;
307
308	ub = rcu_dereference_rtnl(b->media_ptr);
309	if (!ub)
310		return -ENODEV;
311
312	rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
313	if (!rcast)
314		return -ENOMEM;
315
316	if (dst_cache_init(&rcast->dst_cache, GFP_ATOMIC)) {
317		kfree(rcast);
318		return -ENOMEM;
319	}
320
321	memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
322
323	if (ntohs(addr->proto) == ETH_P_IP)
324		pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
325#if IS_ENABLED(CONFIG_IPV6)
326	else if (ntohs(addr->proto) == ETH_P_IPV6)
327		pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
328#endif
329	b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
330	list_add_rcu(&rcast->list, &ub->rcast.list);
331	return 0;
332}
333
334static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
335{
336	struct udp_media_addr src = {0};
337	struct udp_media_addr *dst;
338
339	dst = (struct udp_media_addr *)&b->bcast_addr.value;
340	if (tipc_udp_is_mcast_addr(dst))
341		return 0;
342
343	src.port = udp_hdr(skb)->source;
344
345	if (ip_hdr(skb)->version == 4) {
346		struct iphdr *iphdr = ip_hdr(skb);
347
348		src.proto = htons(ETH_P_IP);
349		src.ipv4.s_addr = iphdr->saddr;
350		if (ipv4_is_multicast(iphdr->daddr))
351			return 0;
352#if IS_ENABLED(CONFIG_IPV6)
353	} else if (ip_hdr(skb)->version == 6) {
354		struct ipv6hdr *iphdr = ipv6_hdr(skb);
355
356		src.proto = htons(ETH_P_IPV6);
357		src.ipv6 = iphdr->saddr;
358		if (ipv6_addr_is_multicast(&iphdr->daddr))
359			return 0;
360#endif
361	} else {
362		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
363	}
 
364
365	if (likely(tipc_udp_is_known_peer(b, &src)))
366		return 0;
367
368	return tipc_udp_rcast_add(b, &src);
369}
370
371/* tipc_udp_recv - read data from bearer socket */
372static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
373{
374	struct udp_bearer *ub;
375	struct tipc_bearer *b;
376	struct tipc_msg *hdr;
377	int err;
378
379	ub = rcu_dereference_sk_user_data(sk);
380	if (!ub) {
381		pr_err_ratelimited("Failed to get UDP bearer reference");
382		goto out;
 
383	}
384	skb_pull(skb, sizeof(struct udphdr));
385	hdr = buf_msg(skb);
386
387	b = rcu_dereference(ub->bearer);
388	if (!b)
389		goto out;
390
391	if (b && test_bit(0, &b->up)) {
392		TIPC_SKB_CB(skb)->flags = 0;
393		tipc_rcv(sock_net(sk), skb, b);
 
394		return 0;
395	}
396
397	if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
398		err = tipc_udp_rcast_disc(b, skb);
399		if (err)
400			goto out;
401	}
402
403out:
404	kfree_skb(skb);
405	return 0;
406}
407
408static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
409{
410	int err = 0;
411	struct ip_mreqn mreqn;
412	struct sock *sk = ub->ubsock->sk;
413
414	if (ntohs(remote->proto) == ETH_P_IP) {
 
 
415		mreqn.imr_multiaddr = remote->ipv4;
416		mreqn.imr_ifindex = ub->ifindex;
417		err = ip_mc_join_group(sk, &mreqn);
418#if IS_ENABLED(CONFIG_IPV6)
419	} else {
420		lock_sock(sk);
 
421		err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
422						   &remote->ipv6);
423		release_sock(sk);
424#endif
425	}
426	return err;
427}
428
429static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
430				  struct udp_media_addr *addr, int nla_t)
431{
432	if (ntohs(addr->proto) == ETH_P_IP) {
433		struct sockaddr_in ip4;
434
435		memset(&ip4, 0, sizeof(ip4));
436		ip4.sin_family = AF_INET;
437		ip4.sin_port = addr->port;
438		ip4.sin_addr.s_addr = addr->ipv4.s_addr;
439		if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
440			return -EMSGSIZE;
441
442#if IS_ENABLED(CONFIG_IPV6)
443	} else if (ntohs(addr->proto) == ETH_P_IPV6) {
444		struct sockaddr_in6 ip6;
445
446		memset(&ip6, 0, sizeof(ip6));
447		ip6.sin6_family = AF_INET6;
448		ip6.sin6_port  = addr->port;
449		memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
450		if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
451			return -EMSGSIZE;
452#endif
453	}
454
455	return 0;
456}
457
458int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
459{
460	u32 bid = cb->args[0];
461	u32 skip_cnt = cb->args[1];
462	u32 portid = NETLINK_CB(cb->skb).portid;
463	struct udp_replicast *rcast, *tmp;
464	struct tipc_bearer *b;
465	struct udp_bearer *ub;
466	void *hdr;
467	int err;
468	int i;
469
470	if (!bid && !skip_cnt) {
471		struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
472		struct net *net = sock_net(skb->sk);
473		struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
474		char *bname;
475
476		if (!attrs[TIPC_NLA_BEARER])
477			return -EINVAL;
478
479		err = nla_parse_nested_deprecated(battrs, TIPC_NLA_BEARER_MAX,
480						  attrs[TIPC_NLA_BEARER],
481						  tipc_nl_bearer_policy, NULL);
482		if (err)
483			return err;
484
485		if (!battrs[TIPC_NLA_BEARER_NAME])
486			return -EINVAL;
487
488		bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
489
490		rtnl_lock();
491		b = tipc_bearer_find(net, bname);
492		if (!b) {
493			rtnl_unlock();
494			return -EINVAL;
495		}
496		bid = b->identity;
 
 
 
 
497	} else {
498		struct net *net = sock_net(skb->sk);
499		struct tipc_net *tn = net_generic(net, tipc_net_id);
500
501		rtnl_lock();
502		b = rtnl_dereference(tn->bearer_list[bid]);
503		if (!b) {
504			rtnl_unlock();
505			return -EINVAL;
506		}
507	}
508
509	ub = rtnl_dereference(b->media_ptr);
510	if (!ub) {
511		rtnl_unlock();
512		return -EINVAL;
513	}
 
 
514
515	i = 0;
516	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
517		if (i < skip_cnt)
518			goto count;
519
520		hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
521				  &tipc_genl_family, NLM_F_MULTI,
522				  TIPC_NL_BEARER_GET);
523		if (!hdr)
524			goto done;
525
526		err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
527					     TIPC_NLA_UDP_REMOTE);
528		if (err) {
529			genlmsg_cancel(skb, hdr);
530			goto done;
531		}
532		genlmsg_end(skb, hdr);
533count:
534		i++;
535	}
536done:
537	rtnl_unlock();
538	cb->args[0] = bid;
539	cb->args[1] = i;
540
541	return skb->len;
542}
543
544int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
545{
546	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
547	struct udp_media_addr *dst;
548	struct udp_bearer *ub;
549	struct nlattr *nest;
550
551	ub = rtnl_dereference(b->media_ptr);
552	if (!ub)
553		return -ENODEV;
554
555	nest = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
556	if (!nest)
557		goto msg_full;
558
559	if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
560		goto msg_full;
561
562	dst = (struct udp_media_addr *)&b->bcast_addr.value;
563	if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
564		goto msg_full;
565
566	if (!list_empty(&ub->rcast.list)) {
567		if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
568			goto msg_full;
569	}
570
571	nla_nest_end(msg->skb, nest);
572	return 0;
573msg_full:
574	nla_nest_cancel(msg->skb, nest);
575	return -EMSGSIZE;
576}
577
578/**
579 * tipc_parse_udp_addr - build udp media address from netlink data
580 * @nla:	netlink attribute containing sockaddr storage aligned address
581 * @addr:	tipc media address to fill with address, port and protocol type
582 * @scope_id:	IPv6 scope id pointer, not NULL indicates it's required
583 */
584
585static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
586			       u32 *scope_id)
587{
588	struct sockaddr_storage sa;
589
590	nla_memcpy(&sa, nla, sizeof(sa));
591	if (sa.ss_family == AF_INET) {
592		struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
593
594		addr->proto = htons(ETH_P_IP);
595		addr->port = ip4->sin_port;
596		addr->ipv4.s_addr = ip4->sin_addr.s_addr;
597		return 0;
598
599#if IS_ENABLED(CONFIG_IPV6)
600	} else if (sa.ss_family == AF_INET6) {
601		struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
602
603		addr->proto = htons(ETH_P_IPV6);
604		addr->port = ip6->sin6_port;
605		memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
606
607		/* Scope ID is only interesting for local addresses */
608		if (scope_id) {
609			int atype;
610
611			atype = ipv6_addr_type(&ip6->sin6_addr);
612			if (__ipv6_addr_needs_scope_id(atype) &&
613			    !ip6->sin6_scope_id) {
614				return -EINVAL;
615			}
616
617			*scope_id = ip6->sin6_scope_id ? : 0;
618		}
619
 
 
 
 
 
 
 
 
 
620		return 0;
621#endif
622	}
623	return -EADDRNOTAVAIL;
624}
625
626int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
627{
628	int err;
629	struct udp_media_addr addr = {0};
630	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
631	struct udp_media_addr *dst;
632
633	if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attr, tipc_nl_udp_policy, NULL))
634		return -EINVAL;
635
636	if (!opts[TIPC_NLA_UDP_REMOTE])
637		return -EINVAL;
638
639	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
640	if (err)
641		return err;
642
643	dst = (struct udp_media_addr *)&b->bcast_addr.value;
644	if (tipc_udp_is_mcast_addr(dst)) {
645		pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
646		return -EINVAL;
647	}
648
649	if (tipc_udp_is_known_peer(b, &addr))
650		return 0;
651
652	return tipc_udp_rcast_add(b, &addr);
653}
654
655/**
656 * tipc_udp_enable - callback to create a new udp bearer instance
657 * @net:	network namespace
658 * @b:		pointer to generic tipc_bearer
659 * @attrs:	netlink bearer configuration
660 *
661 * validate the bearer parameters and initialize the udp bearer
662 * rtnl_lock should be held
663 */
664static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
665			   struct nlattr *attrs[])
666{
667	int err = -EINVAL;
668	struct udp_bearer *ub;
669	struct udp_media_addr remote = {0};
670	struct udp_media_addr local = {0};
671	struct udp_port_cfg udp_conf = {0};
672	struct udp_tunnel_sock_cfg tuncfg = {NULL};
673	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
674	u8 node_id[NODE_ID_LEN] = {0,};
675	struct net_device *dev;
676	int rmcast = 0;
677
678	ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
679	if (!ub)
680		return -ENOMEM;
681
682	INIT_LIST_HEAD(&ub->rcast.list);
683
684	if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
685		goto err;
686
687	if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attrs[TIPC_NLA_BEARER_UDP_OPTS], tipc_nl_udp_policy, NULL))
688		goto err;
689
690	if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
691		pr_err("Invalid UDP bearer configuration");
692		err = -EINVAL;
693		goto err;
694	}
695
696	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
697				  &ub->ifindex);
698	if (err)
699		goto err;
700
701	err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
702	if (err)
703		goto err;
704
705	if (remote.proto != local.proto) {
706		err = -EINVAL;
707		goto err;
708	}
709
710	/* Checking remote ip address */
711	rmcast = tipc_udp_is_mcast_addr(&remote);
712
713	/* Autoconfigure own node identity if needed */
714	if (!tipc_own_id(net)) {
715		memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
716		tipc_net_init(net, node_id, 0);
717	}
718	if (!tipc_own_id(net)) {
719		pr_warn("Failed to set node id, please configure manually\n");
720		err = -EINVAL;
721		goto err;
722	}
723
724	b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
725	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
726	rcu_assign_pointer(b->media_ptr, ub);
727	rcu_assign_pointer(ub->bearer, b);
728	tipc_udp_media_addr_set(&b->addr, &local);
729	if (local.proto == htons(ETH_P_IP)) {
 
 
730		dev = __ip_dev_find(net, local.ipv4.s_addr, false);
731		if (!dev) {
732			err = -ENODEV;
733			goto err;
734		}
735		udp_conf.family = AF_INET;
736
737		/* Switch to use ANY to receive packets from group */
738		if (rmcast)
739			udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
740		else
741			udp_conf.local_ip.s_addr = local.ipv4.s_addr;
742		udp_conf.use_udp_checksums = false;
743		ub->ifindex = dev->ifindex;
744		b->encap_hlen = sizeof(struct iphdr) + sizeof(struct udphdr);
745		b->mtu = b->media->mtu;
746#if IS_ENABLED(CONFIG_IPV6)
747	} else if (local.proto == htons(ETH_P_IPV6)) {
748		dev = ub->ifindex ? __dev_get_by_index(net, ub->ifindex) : NULL;
749		dev = ipv6_dev_find(net, &local.ipv6, dev);
750		if (!dev) {
751			err = -ENODEV;
752			goto err;
753		}
754		udp_conf.family = AF_INET6;
755		udp_conf.use_udp6_tx_checksums = true;
756		udp_conf.use_udp6_rx_checksums = true;
757		if (rmcast)
758			udp_conf.local_ip6 = in6addr_any;
759		else
760			udp_conf.local_ip6 = local.ipv6;
761		ub->ifindex = dev->ifindex;
762		b->encap_hlen = sizeof(struct ipv6hdr) + sizeof(struct udphdr);
763		b->mtu = 1280;
764#endif
765	} else {
766		err = -EAFNOSUPPORT;
767		goto err;
768	}
769	udp_conf.local_udp_port = local.port;
770	err = udp_sock_create(net, &udp_conf, &ub->ubsock);
771	if (err)
772		goto err;
773	tuncfg.sk_user_data = ub;
774	tuncfg.encap_type = 1;
775	tuncfg.encap_rcv = tipc_udp_recv;
776	tuncfg.encap_destroy = NULL;
777	setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
778
779	err = dst_cache_init(&ub->rcast.dst_cache, GFP_ATOMIC);
780	if (err)
781		goto free;
782
783	/*
784	 * The bcast media address port is used for all peers and the ip
785	 * is used if it's a multicast address.
786	 */
787	memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
788	if (rmcast)
789		err = enable_mcast(ub, &remote);
790	else
791		err = tipc_udp_rcast_add(b, &remote);
792	if (err)
793		goto free;
794
795	return 0;
796
797free:
798	dst_cache_destroy(&ub->rcast.dst_cache);
799	udp_tunnel_sock_release(ub->ubsock);
800err:
801	kfree(ub);
802	return err;
803}
804
805/* cleanup_bearer - break the socket/bearer association */
806static void cleanup_bearer(struct work_struct *work)
807{
808	struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
809	struct udp_replicast *rcast, *tmp;
810	struct tipc_net *tn;
811
812	list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
813		dst_cache_destroy(&rcast->dst_cache);
814		list_del_rcu(&rcast->list);
815		kfree_rcu(rcast, rcu);
816	}
817
818	tn = tipc_net(sock_net(ub->ubsock->sk));
819
820	dst_cache_destroy(&ub->rcast.dst_cache);
821	udp_tunnel_sock_release(ub->ubsock);
822
823	/* Note: could use a call_rcu() to avoid another synchronize_net() */
824	synchronize_net();
825	atomic_dec(&tn->wq_count);
826	kfree(ub);
827}
828
829/* tipc_udp_disable - detach bearer from socket */
830static void tipc_udp_disable(struct tipc_bearer *b)
831{
832	struct udp_bearer *ub;
833
834	ub = rtnl_dereference(b->media_ptr);
835	if (!ub) {
836		pr_err("UDP bearer instance not found\n");
837		return;
838	}
839	sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
 
840	RCU_INIT_POINTER(ub->bearer, NULL);
841
842	/* sock_release need to be done outside of rtnl lock */
843	atomic_inc(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
844	INIT_WORK(&ub->work, cleanup_bearer);
845	schedule_work(&ub->work);
846}
847
848struct tipc_media udp_media_info = {
849	.send_msg	= tipc_udp_send_msg,
850	.enable_media	= tipc_udp_enable,
851	.disable_media	= tipc_udp_disable,
852	.addr2str	= tipc_udp_addr2str,
853	.addr2msg	= tipc_udp_addr2msg,
854	.msg2addr	= tipc_udp_msg2addr,
855	.priority	= TIPC_DEF_LINK_PRI,
856	.tolerance	= TIPC_DEF_LINK_TOL,
857	.min_win	= TIPC_DEF_LINK_WIN,
858	.max_win	= TIPC_DEF_LINK_WIN,
859	.mtu		= TIPC_DEF_LINK_UDP_MTU,
860	.type_id	= TIPC_MEDIA_TYPE_UDP,
861	.hwaddr_len	= 0,
862	.name		= "udp"
863};