1 /*
2 * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
3 *
4 * Marek Lindner, Simon Wunderlich
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of version 2 of the GNU General Public
8 * License as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18 * 02110-1301, USA
19 *
20 */
21
22 #include "main.h"
23 #include "hard-interface.h"
24 #include "soft-interface.h"
25 #include "send.h"
26 #include "translation-table.h"
27 #include "routing.h"
28 #include "bat_sysfs.h"
29 #include "originator.h"
30 #include "hash.h"
31
32 #include <linux/if_arp.h>
33
34 /* protect update critical side of hardif_list - but not the content */
35 static DEFINE_SPINLOCK(hardif_list_lock);
36
37
38 static int batman_skb_recv(struct sk_buff *skb,
39 struct net_device *dev,
40 struct packet_type *ptype,
41 struct net_device *orig_dev);
42
hardif_free_rcu(struct rcu_head * rcu)43 void hardif_free_rcu(struct rcu_head *rcu)
44 {
45 struct hard_iface *hard_iface;
46
47 hard_iface = container_of(rcu, struct hard_iface, rcu);
48 dev_put(hard_iface->net_dev);
49 kfree(hard_iface);
50 }
51
hardif_get_by_netdev(struct net_device * net_dev)52 struct hard_iface *hardif_get_by_netdev(struct net_device *net_dev)
53 {
54 struct hard_iface *hard_iface;
55
56 rcu_read_lock();
57 list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
58 if (hard_iface->net_dev == net_dev &&
59 atomic_inc_not_zero(&hard_iface->refcount))
60 goto out;
61 }
62
63 hard_iface = NULL;
64
65 out:
66 rcu_read_unlock();
67 return hard_iface;
68 }
69
is_valid_iface(struct net_device * net_dev)70 static int is_valid_iface(struct net_device *net_dev)
71 {
72 if (net_dev->flags & IFF_LOOPBACK)
73 return 0;
74
75 if (net_dev->type != ARPHRD_ETHER)
76 return 0;
77
78 if (net_dev->addr_len != ETH_ALEN)
79 return 0;
80
81 /* no batman over batman */
82 if (softif_is_valid(net_dev))
83 return 0;
84
85 /* Device is being bridged */
86 /* if (net_dev->priv_flags & IFF_BRIDGE_PORT)
87 return 0; */
88
89 return 1;
90 }
91
hardif_get_active(struct net_device * soft_iface)92 static struct hard_iface *hardif_get_active(struct net_device *soft_iface)
93 {
94 struct hard_iface *hard_iface;
95
96 rcu_read_lock();
97 list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
98 if (hard_iface->soft_iface != soft_iface)
99 continue;
100
101 if (hard_iface->if_status == IF_ACTIVE &&
102 atomic_inc_not_zero(&hard_iface->refcount))
103 goto out;
104 }
105
106 hard_iface = NULL;
107
108 out:
109 rcu_read_unlock();
110 return hard_iface;
111 }
112
update_primary_addr(struct bat_priv * bat_priv)113 static void update_primary_addr(struct bat_priv *bat_priv)
114 {
115 struct vis_packet *vis_packet;
116
117 vis_packet = (struct vis_packet *)
118 bat_priv->my_vis_info->skb_packet->data;
119 memcpy(vis_packet->vis_orig,
120 bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
121 memcpy(vis_packet->sender_orig,
122 bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
123 }
124
set_primary_if(struct bat_priv * bat_priv,struct hard_iface * hard_iface)125 static void set_primary_if(struct bat_priv *bat_priv,
126 struct hard_iface *hard_iface)
127 {
128 struct batman_packet *batman_packet;
129 struct hard_iface *old_if;
130
131 if (hard_iface && !atomic_inc_not_zero(&hard_iface->refcount))
132 hard_iface = NULL;
133
134 old_if = bat_priv->primary_if;
135 bat_priv->primary_if = hard_iface;
136
137 if (old_if)
138 hardif_free_ref(old_if);
139
140 if (!bat_priv->primary_if)
141 return;
142
143 batman_packet = (struct batman_packet *)(hard_iface->packet_buff);
144 batman_packet->flags = PRIMARIES_FIRST_HOP;
145 batman_packet->ttl = TTL;
146
147 update_primary_addr(bat_priv);
148
149 /***
150 * hacky trick to make sure that we send the HNA information via
151 * our new primary interface
152 */
153 atomic_set(&bat_priv->hna_local_changed, 1);
154 }
155
hardif_is_iface_up(struct hard_iface * hard_iface)156 static bool hardif_is_iface_up(struct hard_iface *hard_iface)
157 {
158 if (hard_iface->net_dev->flags & IFF_UP)
159 return true;
160
161 return false;
162 }
163
update_mac_addresses(struct hard_iface * hard_iface)164 static void update_mac_addresses(struct hard_iface *hard_iface)
165 {
166 memcpy(((struct batman_packet *)(hard_iface->packet_buff))->orig,
167 hard_iface->net_dev->dev_addr, ETH_ALEN);
168 memcpy(((struct batman_packet *)(hard_iface->packet_buff))->prev_sender,
169 hard_iface->net_dev->dev_addr, ETH_ALEN);
170 }
171
check_known_mac_addr(struct net_device * net_dev)172 static void check_known_mac_addr(struct net_device *net_dev)
173 {
174 struct hard_iface *hard_iface;
175
176 rcu_read_lock();
177 list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
178 if ((hard_iface->if_status != IF_ACTIVE) &&
179 (hard_iface->if_status != IF_TO_BE_ACTIVATED))
180 continue;
181
182 if (hard_iface->net_dev == net_dev)
183 continue;
184
185 if (!compare_eth(hard_iface->net_dev->dev_addr,
186 net_dev->dev_addr))
187 continue;
188
189 pr_warning("The newly added mac address (%pM) already exists "
190 "on: %s\n", net_dev->dev_addr,
191 hard_iface->net_dev->name);
192 pr_warning("It is strongly recommended to keep mac addresses "
193 "unique to avoid problems!\n");
194 }
195 rcu_read_unlock();
196 }
197
hardif_min_mtu(struct net_device * soft_iface)198 int hardif_min_mtu(struct net_device *soft_iface)
199 {
200 struct bat_priv *bat_priv = netdev_priv(soft_iface);
201 struct hard_iface *hard_iface;
202 /* allow big frames if all devices are capable to do so
203 * (have MTU > 1500 + BAT_HEADER_LEN) */
204 int min_mtu = ETH_DATA_LEN;
205
206 if (atomic_read(&bat_priv->fragmentation))
207 goto out;
208
209 rcu_read_lock();
210 list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
211 if ((hard_iface->if_status != IF_ACTIVE) &&
212 (hard_iface->if_status != IF_TO_BE_ACTIVATED))
213 continue;
214
215 if (hard_iface->soft_iface != soft_iface)
216 continue;
217
218 min_mtu = min_t(int, hard_iface->net_dev->mtu - BAT_HEADER_LEN,
219 min_mtu);
220 }
221 rcu_read_unlock();
222 out:
223 return min_mtu;
224 }
225
226 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
update_min_mtu(struct net_device * soft_iface)227 void update_min_mtu(struct net_device *soft_iface)
228 {
229 int min_mtu;
230
231 min_mtu = hardif_min_mtu(soft_iface);
232 if (soft_iface->mtu != min_mtu)
233 soft_iface->mtu = min_mtu;
234 }
235
hardif_activate_interface(struct hard_iface * hard_iface)236 static void hardif_activate_interface(struct hard_iface *hard_iface)
237 {
238 struct bat_priv *bat_priv;
239
240 if (hard_iface->if_status != IF_INACTIVE)
241 return;
242
243 bat_priv = netdev_priv(hard_iface->soft_iface);
244
245 update_mac_addresses(hard_iface);
246 hard_iface->if_status = IF_TO_BE_ACTIVATED;
247
248 /**
249 * the first active interface becomes our primary interface or
250 * the next active interface after the old primay interface was removed
251 */
252 if (!bat_priv->primary_if)
253 set_primary_if(bat_priv, hard_iface);
254
255 bat_info(hard_iface->soft_iface, "Interface activated: %s\n",
256 hard_iface->net_dev->name);
257
258 update_min_mtu(hard_iface->soft_iface);
259 return;
260 }
261
hardif_deactivate_interface(struct hard_iface * hard_iface)262 static void hardif_deactivate_interface(struct hard_iface *hard_iface)
263 {
264 if ((hard_iface->if_status != IF_ACTIVE) &&
265 (hard_iface->if_status != IF_TO_BE_ACTIVATED))
266 return;
267
268 hard_iface->if_status = IF_INACTIVE;
269
270 bat_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
271 hard_iface->net_dev->name);
272
273 update_min_mtu(hard_iface->soft_iface);
274 }
275
hardif_enable_interface(struct hard_iface * hard_iface,char * iface_name)276 int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name)
277 {
278 struct bat_priv *bat_priv;
279 struct batman_packet *batman_packet;
280 struct net_device *soft_iface;
281 int ret;
282
283 if (hard_iface->if_status != IF_NOT_IN_USE)
284 goto out;
285
286 if (!atomic_inc_not_zero(&hard_iface->refcount))
287 goto out;
288
289 soft_iface = dev_get_by_name(&init_net, iface_name);
290
291 if (!soft_iface) {
292 soft_iface = softif_create(iface_name);
293
294 if (!soft_iface) {
295 ret = -ENOMEM;
296 goto err;
297 }
298
299 /* dev_get_by_name() increases the reference counter for us */
300 dev_hold(soft_iface);
301 }
302
303 if (!softif_is_valid(soft_iface)) {
304 pr_err("Can't create batman mesh interface %s: "
305 "already exists as regular interface\n",
306 soft_iface->name);
307 dev_put(soft_iface);
308 ret = -EINVAL;
309 goto err;
310 }
311
312 hard_iface->soft_iface = soft_iface;
313 bat_priv = netdev_priv(hard_iface->soft_iface);
314 hard_iface->packet_len = BAT_PACKET_LEN;
315 hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
316
317 if (!hard_iface->packet_buff) {
318 bat_err(hard_iface->soft_iface, "Can't add interface packet "
319 "(%s): out of memory\n", hard_iface->net_dev->name);
320 ret = -ENOMEM;
321 goto err;
322 }
323
324 batman_packet = (struct batman_packet *)(hard_iface->packet_buff);
325 batman_packet->packet_type = BAT_PACKET;
326 batman_packet->version = COMPAT_VERSION;
327 batman_packet->flags = 0;
328 batman_packet->ttl = 2;
329 batman_packet->tq = TQ_MAX_VALUE;
330 batman_packet->num_hna = 0;
331
332 hard_iface->if_num = bat_priv->num_ifaces;
333 bat_priv->num_ifaces++;
334 hard_iface->if_status = IF_INACTIVE;
335 orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
336
337 hard_iface->batman_adv_ptype.type = __constant_htons(ETH_P_BATMAN);
338 hard_iface->batman_adv_ptype.func = batman_skb_recv;
339 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
340 dev_add_pack(&hard_iface->batman_adv_ptype);
341
342 atomic_set(&hard_iface->seqno, 1);
343 atomic_set(&hard_iface->frag_seqno, 1);
344 bat_info(hard_iface->soft_iface, "Adding interface: %s\n",
345 hard_iface->net_dev->name);
346
347 if (atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu <
348 ETH_DATA_LEN + BAT_HEADER_LEN)
349 bat_info(hard_iface->soft_iface,
350 "The MTU of interface %s is too small (%i) to handle "
351 "the transport of batman-adv packets. Packets going "
352 "over this interface will be fragmented on layer2 "
353 "which could impact the performance. Setting the MTU "
354 "to %zi would solve the problem.\n",
355 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
356 ETH_DATA_LEN + BAT_HEADER_LEN);
357
358 if (!atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu <
359 ETH_DATA_LEN + BAT_HEADER_LEN)
360 bat_info(hard_iface->soft_iface,
361 "The MTU of interface %s is too small (%i) to handle "
362 "the transport of batman-adv packets. If you experience"
363 " problems getting traffic through try increasing the "
364 "MTU to %zi.\n",
365 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
366 ETH_DATA_LEN + BAT_HEADER_LEN);
367
368 if (hardif_is_iface_up(hard_iface))
369 hardif_activate_interface(hard_iface);
370 else
371 bat_err(hard_iface->soft_iface, "Not using interface %s "
372 "(retrying later): interface not active\n",
373 hard_iface->net_dev->name);
374
375 /* begin scheduling originator messages on that interface */
376 schedule_own_packet(hard_iface);
377
378 out:
379 return 0;
380
381 err:
382 hardif_free_ref(hard_iface);
383 return ret;
384 }
385
hardif_disable_interface(struct hard_iface * hard_iface)386 void hardif_disable_interface(struct hard_iface *hard_iface)
387 {
388 struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
389
390 if (hard_iface->if_status == IF_ACTIVE)
391 hardif_deactivate_interface(hard_iface);
392
393 if (hard_iface->if_status != IF_INACTIVE)
394 return;
395
396 bat_info(hard_iface->soft_iface, "Removing interface: %s\n",
397 hard_iface->net_dev->name);
398 dev_remove_pack(&hard_iface->batman_adv_ptype);
399
400 bat_priv->num_ifaces--;
401 orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
402
403 if (hard_iface == bat_priv->primary_if) {
404 struct hard_iface *new_if;
405
406 new_if = hardif_get_active(hard_iface->soft_iface);
407 set_primary_if(bat_priv, new_if);
408
409 if (new_if)
410 hardif_free_ref(new_if);
411 }
412
413 kfree(hard_iface->packet_buff);
414 hard_iface->packet_buff = NULL;
415 hard_iface->if_status = IF_NOT_IN_USE;
416
417 /* delete all references to this hard_iface */
418 purge_orig_ref(bat_priv);
419 purge_outstanding_packets(bat_priv, hard_iface);
420 dev_put(hard_iface->soft_iface);
421
422 /* nobody uses this interface anymore */
423 if (!bat_priv->num_ifaces)
424 softif_destroy(hard_iface->soft_iface);
425
426 hard_iface->soft_iface = NULL;
427 hardif_free_ref(hard_iface);
428 }
429
hardif_add_interface(struct net_device * net_dev)430 static struct hard_iface *hardif_add_interface(struct net_device *net_dev)
431 {
432 struct hard_iface *hard_iface;
433 int ret;
434
435 ret = is_valid_iface(net_dev);
436 if (ret != 1)
437 goto out;
438
439 dev_hold(net_dev);
440
441 hard_iface = kmalloc(sizeof(struct hard_iface), GFP_ATOMIC);
442 if (!hard_iface) {
443 pr_err("Can't add interface (%s): out of memory\n",
444 net_dev->name);
445 goto release_dev;
446 }
447
448 ret = sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
449 if (ret)
450 goto free_if;
451
452 hard_iface->if_num = -1;
453 hard_iface->net_dev = net_dev;
454 hard_iface->soft_iface = NULL;
455 hard_iface->if_status = IF_NOT_IN_USE;
456 INIT_LIST_HEAD(&hard_iface->list);
457 /* extra reference for return */
458 atomic_set(&hard_iface->refcount, 2);
459
460 check_known_mac_addr(hard_iface->net_dev);
461
462 spin_lock(&hardif_list_lock);
463 list_add_tail_rcu(&hard_iface->list, &hardif_list);
464 spin_unlock(&hardif_list_lock);
465
466 return hard_iface;
467
468 free_if:
469 kfree(hard_iface);
470 release_dev:
471 dev_put(net_dev);
472 out:
473 return NULL;
474 }
475
hardif_remove_interface(struct hard_iface * hard_iface)476 static void hardif_remove_interface(struct hard_iface *hard_iface)
477 {
478 /* first deactivate interface */
479 if (hard_iface->if_status != IF_NOT_IN_USE)
480 hardif_disable_interface(hard_iface);
481
482 if (hard_iface->if_status != IF_NOT_IN_USE)
483 return;
484
485 hard_iface->if_status = IF_TO_BE_REMOVED;
486 sysfs_del_hardif(&hard_iface->hardif_obj);
487 hardif_free_ref(hard_iface);
488 }
489
hardif_remove_interfaces(void)490 void hardif_remove_interfaces(void)
491 {
492 struct hard_iface *hard_iface, *hard_iface_tmp;
493 struct list_head if_queue;
494
495 INIT_LIST_HEAD(&if_queue);
496
497 spin_lock(&hardif_list_lock);
498 list_for_each_entry_safe(hard_iface, hard_iface_tmp,
499 &hardif_list, list) {
500 list_del_rcu(&hard_iface->list);
501 list_add_tail(&hard_iface->list, &if_queue);
502 }
503 spin_unlock(&hardif_list_lock);
504
505 rtnl_lock();
506 list_for_each_entry_safe(hard_iface, hard_iface_tmp, &if_queue, list) {
507 hardif_remove_interface(hard_iface);
508 }
509 rtnl_unlock();
510 }
511
hard_if_event(struct notifier_block * this,unsigned long event,void * ptr)512 static int hard_if_event(struct notifier_block *this,
513 unsigned long event, void *ptr)
514 {
515 struct net_device *net_dev = (struct net_device *)ptr;
516 struct hard_iface *hard_iface = hardif_get_by_netdev(net_dev);
517 struct bat_priv *bat_priv;
518
519 if (!hard_iface && event == NETDEV_REGISTER)
520 hard_iface = hardif_add_interface(net_dev);
521
522 if (!hard_iface)
523 goto out;
524
525 switch (event) {
526 case NETDEV_UP:
527 hardif_activate_interface(hard_iface);
528 break;
529 case NETDEV_GOING_DOWN:
530 case NETDEV_DOWN:
531 hardif_deactivate_interface(hard_iface);
532 break;
533 case NETDEV_UNREGISTER:
534 spin_lock(&hardif_list_lock);
535 list_del_rcu(&hard_iface->list);
536 spin_unlock(&hardif_list_lock);
537
538 hardif_remove_interface(hard_iface);
539 break;
540 case NETDEV_CHANGEMTU:
541 if (hard_iface->soft_iface)
542 update_min_mtu(hard_iface->soft_iface);
543 break;
544 case NETDEV_CHANGEADDR:
545 if (hard_iface->if_status == IF_NOT_IN_USE)
546 goto hardif_put;
547
548 check_known_mac_addr(hard_iface->net_dev);
549 update_mac_addresses(hard_iface);
550
551 bat_priv = netdev_priv(hard_iface->soft_iface);
552 if (hard_iface == bat_priv->primary_if)
553 update_primary_addr(bat_priv);
554 break;
555 default:
556 break;
557 };
558
559 hardif_put:
560 hardif_free_ref(hard_iface);
561 out:
562 return NOTIFY_DONE;
563 }
564
565 /* receive a packet with the batman ethertype coming on a hard
566 * interface */
batman_skb_recv(struct sk_buff * skb,struct net_device * dev,struct packet_type * ptype,struct net_device * orig_dev)567 static int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
568 struct packet_type *ptype,
569 struct net_device *orig_dev)
570 {
571 struct bat_priv *bat_priv;
572 struct batman_packet *batman_packet;
573 struct hard_iface *hard_iface;
574 int ret;
575
576 hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype);
577 skb = skb_share_check(skb, GFP_ATOMIC);
578
579 /* skb was released by skb_share_check() */
580 if (!skb)
581 goto err_out;
582
583 /* packet should hold at least type and version */
584 if (unlikely(!pskb_may_pull(skb, 2)))
585 goto err_free;
586
587 /* expect a valid ethernet header here. */
588 if (unlikely(skb->mac_len != sizeof(struct ethhdr)
589 || !skb_mac_header(skb)))
590 goto err_free;
591
592 if (!hard_iface->soft_iface)
593 goto err_free;
594
595 bat_priv = netdev_priv(hard_iface->soft_iface);
596
597 if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
598 goto err_free;
599
600 /* discard frames on not active interfaces */
601 if (hard_iface->if_status != IF_ACTIVE)
602 goto err_free;
603
604 batman_packet = (struct batman_packet *)skb->data;
605
606 if (batman_packet->version != COMPAT_VERSION) {
607 bat_dbg(DBG_BATMAN, bat_priv,
608 "Drop packet: incompatible batman version (%i)\n",
609 batman_packet->version);
610 goto err_free;
611 }
612
613 /* all receive handlers return whether they received or reused
614 * the supplied skb. if not, we have to free the skb. */
615
616 switch (batman_packet->packet_type) {
617 /* batman originator packet */
618 case BAT_PACKET:
619 ret = recv_bat_packet(skb, hard_iface);
620 break;
621
622 /* batman icmp packet */
623 case BAT_ICMP:
624 ret = recv_icmp_packet(skb, hard_iface);
625 break;
626
627 /* unicast packet */
628 case BAT_UNICAST:
629 ret = recv_unicast_packet(skb, hard_iface);
630 break;
631
632 /* fragmented unicast packet */
633 case BAT_UNICAST_FRAG:
634 ret = recv_ucast_frag_packet(skb, hard_iface);
635 break;
636
637 /* broadcast packet */
638 case BAT_BCAST:
639 ret = recv_bcast_packet(skb, hard_iface);
640 break;
641
642 /* vis packet */
643 case BAT_VIS:
644 ret = recv_vis_packet(skb, hard_iface);
645 break;
646 default:
647 ret = NET_RX_DROP;
648 }
649
650 if (ret == NET_RX_DROP)
651 kfree_skb(skb);
652
653 /* return NET_RX_SUCCESS in any case as we
654 * most probably dropped the packet for
655 * routing-logical reasons. */
656
657 return NET_RX_SUCCESS;
658
659 err_free:
660 kfree_skb(skb);
661 err_out:
662 return NET_RX_DROP;
663 }
664
665 struct notifier_block hard_if_notifier = {
666 .notifier_call = hard_if_event,
667 };
668