aboutsummaryrefslogtreecommitdiff
path: root/net/tipc/bearer.c
blob: 574b86193b15a8251dc85555cc03a8e5f9af1768 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
/*
 * net/tipc/bearer.c: TIPC bearer code
 *
 * Copyright (c) 1996-2006, 2013, Ericsson AB
 * Copyright (c) 2004-2006, 2010-2013, Wind River Systems
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "core.h"
#include "config.h"
#include "bearer.h"
#include "discover.h"

#define MAX_ADDR_STR 60

static struct tipc_media * const media_info_array[] = {
	&eth_media_info,
#ifdef CONFIG_TIPC_MEDIA_IB
	&ib_media_info,
#endif
	NULL
};

struct tipc_bearer tipc_bearers[MAX_BEARERS];

static void bearer_disable(struct tipc_bearer *b_ptr);

/**
 * tipc_media_find - locates specified media object by name
 */
struct tipc_media *tipc_media_find(const char *name)
{
	u32 i;

	for (i = 0; media_info_array[i] != NULL; i++) {
		if (!strcmp(media_info_array[i]->name, name))
			break;
	}
	return media_info_array[i];
}

/**
 * media_find_id - locates specified media object by type identifier
 */
static struct tipc_media *media_find_id(u8 type)
{
	u32 i;

	for (i = 0; media_info_array[i] != NULL; i++) {
		if (media_info_array[i]->type_id == type)
			break;
	}
	return media_info_array[i];
}

/**
 * tipc_media_addr_printf - record media address in print buffer
 */
void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
{
	char addr_str[MAX_ADDR_STR];
	struct tipc_media *m_ptr;
	int ret;

	m_ptr = media_find_id(a->media_id);

	if (m_ptr && !m_ptr->addr2str(a, addr_str, sizeof(addr_str)))
		ret = tipc_snprintf(buf, len, "%s(%s)", m_ptr->name, addr_str);
	else {
		u32 i;

		ret = tipc_snprintf(buf, len, "UNKNOWN(%u)", a->media_id);
		for (i = 0; i < sizeof(a->value); i++)
			ret += tipc_snprintf(buf - ret, len + ret,
					    "-%02x", a->value[i]);
	}
}

/**
 * tipc_media_get_names - record names of registered media in buffer
 */
struct sk_buff *tipc_media_get_names(void)
{
	struct sk_buff *buf;
	int i;

	buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
	if (!buf)
		return NULL;

	for (i = 0; media_info_array[i] != NULL; i++) {
		tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME,
				    media_info_array[i]->name,
				    strlen(media_info_array[i]->name) + 1);
	}
	return buf;
}

/**
 * bearer_name_validate - validate & (optionally) deconstruct bearer name
 * @name: ptr to bearer name string
 * @name_parts: ptr to area for bearer name components (or NULL if not needed)
 *
 * Returns 1 if bearer name is valid, otherwise 0.
 */
static int bearer_name_validate(const char *name,
				struct tipc_bearer_names *name_parts)
{
	char name_copy[TIPC_MAX_BEARER_NAME];
	char *media_name;
	char *if_name;
	u32 media_len;
	u32 if_len;

	/* copy bearer name & ensure length is OK */
	name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
	/* need above in case non-Posix strncpy() doesn't pad with nulls */
	strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
	if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
		return 0;

	/* ensure all component parts of bearer name are present */
	media_name = name_copy;
	if_name = strchr(media_name, ':');
	if (if_name == NULL)
		return 0;
	*(if_name++) = 0;
	media_len = if_name - media_name;
	if_len = strlen(if_name) + 1;

	/* validate component parts of bearer name */
	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
		return 0;

	/* return bearer name components, if necessary */
	if (name_parts) {
		strcpy(name_parts->media_name, media_name);
		strcpy(name_parts->if_name, if_name);
	}
	return 1;
}

/**
 * tipc_bearer_find - locates bearer object with matching bearer name
 */
struct tipc_bearer *tipc_bearer_find(const char *name)
{
	struct tipc_bearer *b_ptr;
	u32 i;

	for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
		if (b_ptr->active && (!strcmp(b_ptr->name, name)))
			return b_ptr;
	}
	return NULL;
}

/**
 * tipc_bearer_get_names - record names of bearers in buffer
 */
struct sk_buff *tipc_bearer_get_names(void)
{
	struct sk_buff *buf;
	struct tipc_bearer *b;
	int i, j;

	buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
	if (!buf)
		return NULL;

	read_lock_bh(&tipc_net_lock);
	for (i = 0; media_info_array[i] != NULL; i++) {
		for (j = 0; j < MAX_BEARERS; j++) {
			b = &tipc_bearers[j];
			if (b->active && (b->media == media_info_array[i])) {
				tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
						    b->name,
						    strlen(b->name) + 1);
			}
		}
	}
	read_unlock_bh(&tipc_net_lock);
	return buf;
}

void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest)
{
	tipc_nmap_add(&b_ptr->nodes, dest);
	tipc_bcbearer_sort();
	tipc_disc_add_dest(b_ptr->link_req);
}

void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest)
{
	tipc_nmap_remove(&b_ptr->nodes, dest);
	tipc_bcbearer_sort();
	tipc_disc_remove_dest(b_ptr->link_req);
}

/**
 * tipc_enable_bearer - enable bearer with the given name
 */
int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
{
	struct tipc_bearer *b_ptr;
	struct tipc_media *m_ptr;
	struct tipc_bearer_names b_names;
	char addr_string[16];
	u32 bearer_id;
	u32 with_this_prio;
	u32 i;
	int res = -EINVAL;

	if (!tipc_own_addr) {
		pr_warn("Bearer <%s> rejected, not supported in standalone mode\n",
			name);
		return -ENOPROTOOPT;
	}
	if (!bearer_name_validate(name, &b_names)) {
		pr_warn("Bearer <%s> rejected, illegal name\n", name);
		return -EINVAL;
	}
	if (tipc_addr_domain_valid(disc_domain) &&
	    (disc_domain != tipc_own_addr)) {
		if (tipc_in_scope(disc_domain, tipc_own_addr)) {
			disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
			res = 0;   /* accept any node in own cluster */
		} else if (in_own_cluster_exact(disc_domain))
			res = 0;   /* accept specified node in own cluster */
	}
	if (res) {
		pr_warn("Bearer <%s> rejected, illegal discovery domain\n",
			name);
		return -EINVAL;
	}
	if ((priority > TIPC_MAX_LINK_PRI) &&
	    (priority != TIPC_MEDIA_LINK_PRI)) {
		pr_warn("Bearer <%s> rejected, illegal priority\n", name);
		return -EINVAL;
	}

	write_lock_bh(&tipc_net_lock);

	m_ptr = tipc_media_find(b_names.media_name);
	if (!m_ptr) {
		pr_warn("Bearer <%s> rejected, media <%s> not registered\n",
			name, b_names.media_name);
		goto exit;
	}

	if (priority == TIPC_MEDIA_LINK_PRI)
		priority = m_ptr->priority;

restart:
	bearer_id = MAX_BEARERS;
	with_this_prio = 1;
	for (i = MAX_BEARERS; i-- != 0; ) {
		if (!tipc_bearers[i].active) {
			bearer_id = i;
			continue;
		}
		if (!strcmp(name, tipc_bearers[i].name)) {
			pr_warn("Bearer <%s> rejected, already enabled\n",
				name);
			goto exit;
		}
		if ((tipc_bearers[i].priority == priority) &&
		    (++with_this_prio > 2)) {
			if (priority-- == 0) {
				pr_warn("Bearer <%s> rejected, duplicate priority\n",
					name);
				goto exit;
			}
			pr_warn("Bearer <%s> priority adjustment required %u->%u\n",
				name, priority + 1, priority);
			goto restart;
		}
	}
	if (bearer_id >= MAX_BEARERS) {
		pr_warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
			name, MAX_BEARERS);
		goto exit;
	}

	b_ptr = &tipc_bearers[bearer_id];
	strcpy(b_ptr->name, name);
	b_ptr->media = m_ptr;
	res = m_ptr->enable_media(b_ptr);
	if (res) {
		pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
			name, -res);
		goto exit;
	}

	b_ptr->identity = bearer_id;
	b_ptr->tolerance = m_ptr->tolerance;
	b_ptr->window = m_ptr->window;
	b_ptr->net_plane = bearer_id + 'A';
	b_ptr->active = 1;
	b_ptr->priority = priority;
	INIT_LIST_HEAD(&b_ptr->links);
	spin_lock_init(&b_ptr->lock);

	res = tipc_disc_create(b_ptr, &b_ptr->bcast_addr, disc_domain);
	if (res) {
		bearer_disable(b_ptr);
		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
			name);
		goto exit;
	}
	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
		name,
		tipc_addr_string_fill(addr_string, disc_domain), priority);
exit:
	write_unlock_bh(&tipc_net_lock);
	return res;
}

/**
 * tipc_reset_bearer - Reset all links established over this bearer
 */
static int tipc_reset_bearer(struct tipc_bearer *b_ptr)
{
	struct tipc_link *l_ptr;
	struct tipc_link *temp_l_ptr;

	read_lock_bh(&tipc_net_lock);
	pr_info("Resetting bearer <%s>\n", b_ptr->name);
	spin_lock_bh(&b_ptr->lock);
	list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
		struct tipc_node *n_ptr = l_ptr->owner;

		spin_lock_bh(&n_ptr->lock);
		tipc_link_reset(l_ptr);
		spin_unlock_bh(&n_ptr->lock);
	}
	spin_unlock_bh(&b_ptr->lock);
	read_unlock_bh(&tipc_net_lock);
	return 0;
}

/**
 * bearer_disable
 *
 * Note: This routine assumes caller holds tipc_net_lock.
 */
static void bearer_disable(struct tipc_bearer *b_ptr)
{
	struct tipc_link *l_ptr;
	struct tipc_link *temp_l_ptr;
	struct tipc_link_req *temp_req;

	pr_info("Disabling bearer <%s>\n", b_ptr->name);
	spin_lock_bh(&b_ptr->lock);
	b_ptr->media->disable_media(b_ptr);
	list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
		tipc_link_delete(l_ptr);
	}
	temp_req = b_ptr->link_req;
	b_ptr->link_req = NULL;
	spin_unlock_bh(&b_ptr->lock);

	if (temp_req)
		tipc_disc_delete(temp_req);

	memset(b_ptr, 0, sizeof(struct tipc_bearer));
}

int tipc_disable_bearer(const char *name)
{
	struct tipc_bearer *b_ptr;
	int res;

	write_lock_bh(&tipc_net_lock);
	b_ptr = tipc_bearer_find(name);
	if (b_ptr == NULL) {
		pr_warn("Attempt to disable unknown bearer <%s>\n", name);
		res = -EINVAL;
	} else {
		bearer_disable(b_ptr);
		res = 0;
	}
	write_unlock_bh(&tipc_net_lock);
	return res;
}


/* tipc_l2_media_addr_set - initialize Ethernet media address structure
 *
 * Media-dependent "value" field stores MAC address in first 6 bytes
 * and zeroes out the remaining bytes.
 */
void tipc_l2_media_addr_set(const struct tipc_bearer *b,
			    struct tipc_media_addr *a, char *mac)
{
	int len = b->media->hwaddr_len;

	if (unlikely(sizeof(a->value) < len)) {
		WARN_ONCE(1, "Media length invalid\n");
		return;
	}

	memcpy(a->value, mac, len);
	memset(a->value + len, 0, sizeof(a->value) - len);
	a->media_id = b->media->type_id;
	a->broadcast = !memcmp(mac, b->bcast_addr.value, len);
}

int tipc_enable_l2_media(struct tipc_bearer *b)
{
	struct net_device *dev;
	char *driver_name = strchr((const char *)b->name, ':') + 1;

	/* Find device with specified name */
	dev = dev_get_by_name(&init_net, driver_name);
	if (!dev)
		return -ENODEV;

	/* Associate TIPC bearer with Ethernet bearer */
	b->media_ptr = dev;
	memset(b->bcast_addr.value, 0, sizeof(b->bcast_addr.value));
	memcpy(b->bcast_addr.value, dev->broadcast, b->media->hwaddr_len);
	b->bcast_addr.media_id = b->media->type_id;
	b->bcast_addr.broadcast = 1;
	b->mtu = dev->mtu;
	tipc_l2_media_addr_set(b, &b->addr, (char *)dev->dev_addr);
	rcu_assign_pointer(dev->tipc_ptr, b);
	return 0;
}

/* tipc_disable_l2_media - detach TIPC bearer from an Ethernet interface
 *
 * Mark Ethernet bearer as inactive so that incoming buffers are thrown away,
 * then get worker thread to complete bearer cleanup.  (Can't do cleanup
 * here because cleanup code needs to sleep and caller holds spinlocks.)
 */
void tipc_disable_l2_media(struct tipc_bearer *b)
{
	struct net_device *dev = (struct net_device *)b->media_ptr;
	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
	dev_put(dev);
}

/**
 * tipc_l2_send_msg - send a TIPC packet out over an Ethernet interface
 * @buf: the packet to be sent
 * @b_ptr: the bearer through which the packet is to be sent
 * @dest: peer destination address
 */
int tipc_l2_send_msg(struct sk_buff *buf, struct tipc_bearer *b,
		     struct tipc_media_addr *dest)
{
	struct sk_buff *clone;
	int delta;
	struct net_device *dev = (struct net_device *)b->media_ptr;

	clone = skb_clone(buf, GFP_ATOMIC);
	if (!clone)
		return 0;

	delta = dev->hard_header_len - skb_headroom(buf);
	if ((delta > 0) &&
	    pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
		kfree_skb(clone);
		return 0;
	}

	skb_reset_network_header(clone);
	clone->dev = dev;
	clone->protocol = htons(ETH_P_TIPC);
	dev_hard_header(clone, dev, ETH_P_TIPC, dest->value,
			dev->dev_addr, clone->len);
	dev_queue_xmit(clone);
	return 0;
}

/* tipc_bearer_send- sends buffer to destination over bearer
 *
 * IMPORTANT:
 * The media send routine must not alter the buffer being passed in
 * as it may be needed for later retransmission!
 */
void tipc_bearer_send(struct tipc_bearer *b, struct sk_buff *buf,
		      struct tipc_media_addr *dest)
{
	b->media->send_msg(buf, b, dest);
}

/**
 * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
 * @buf: the received packet
 * @dev: the net device that the packet was received on
 * @pt: the packet_type structure which was used to register this handler
 * @orig_dev: the original receive net device in case the device is a bond
 *
 * Accept only packets explicitly sent to this node, or broadcast packets;
 * ignores packets sent using interface multicast, and traffic sent to other
 * nodes (which can happen if interface is running in promiscuous mode).
 */
static int tipc_l2_rcv_msg(struct sk_buff *buf, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
{
	struct tipc_bearer *b_ptr;

	if (!net_eq(dev_net(dev), &init_net)) {
		kfree_skb(buf);
		return NET_RX_DROP;
	}

	rcu_read_lock();
	b_ptr = rcu_dereference(dev->tipc_ptr);
	if (likely(b_ptr)) {
		if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
			buf->next = NULL;
			tipc_rcv(buf, b_ptr);
			rcu_read_unlock();
			return NET_RX_SUCCESS;
		}
	}
	rcu_read_unlock();

	kfree_skb(buf);
	return NET_RX_DROP;
}

/**
 * tipc_l2_device_event - handle device events from network device
 * @nb: the context of the notification
 * @evt: the type of event
 * @ptr: the net device that the event was on
 *
 * This function is called by the Ethernet driver in case of link
 * change event.
 */
static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
				void *ptr)
{
	struct tipc_bearer *b_ptr;
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);

	if (!net_eq(dev_net(dev), &init_net))
		return NOTIFY_DONE;

	rcu_read_lock();
	b_ptr = rcu_dereference(dev->tipc_ptr);
	if (!b_ptr) {
		rcu_read_unlock();
		return NOTIFY_DONE;
	}

	b_ptr->mtu = dev->mtu;

	switch (evt) {
	case NETDEV_CHANGE:
		if (netif_carrier_ok(dev))
			break;
	case NETDEV_DOWN:
	case NETDEV_CHANGEMTU:
	case NETDEV_CHANGEADDR:
		tipc_reset_bearer(b_ptr);
		break;
	case NETDEV_UNREGISTER:
	case NETDEV_CHANGENAME:
		tipc_disable_bearer(b_ptr->name);
		break;
	}
	rcu_read_unlock();

	return NOTIFY_OK;
}

static struct packet_type tipc_packet_type __read_mostly = {
	.type = __constant_htons(ETH_P_TIPC),
	.func = tipc_l2_rcv_msg,
};

static struct notifier_block notifier = {
	.notifier_call  = tipc_l2_device_event,
	.priority	= 0,
};

int tipc_bearer_setup(void)
{
	int err;

	err = register_netdevice_notifier(&notifier);
	if (err)
		return err;
	dev_add_pack(&tipc_packet_type);
	return 0;
}

void tipc_bearer_cleanup(void)
{
	unregister_netdevice_notifier(&notifier);
	dev_remove_pack(&tipc_packet_type);
}

void tipc_bearer_stop(void)
{
	u32 i;

	for (i = 0; i < MAX_BEARERS; i++) {
		if (tipc_bearers[i].active)
			bearer_disable(&tipc_bearers[i]);
	}
}