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18#include "gateway_client.h"
19#include "main.h"
20
21#include <linux/atomic.h>
22#include <linux/byteorder/generic.h>
23#include <linux/errno.h>
24#include <linux/etherdevice.h>
25#include <linux/fs.h>
26#include <linux/if_ether.h>
27#include <linux/if_vlan.h>
28#include <linux/in.h>
29#include <linux/ip.h>
30#include <linux/ipv6.h>
31#include <linux/kernel.h>
32#include <linux/kref.h>
33#include <linux/list.h>
34#include <linux/netdevice.h>
35#include <linux/netlink.h>
36#include <linux/rculist.h>
37#include <linux/rcupdate.h>
38#include <linux/seq_file.h>
39#include <linux/skbuff.h>
40#include <linux/slab.h>
41#include <linux/spinlock.h>
42#include <linux/stddef.h>
43#include <linux/udp.h>
44#include <net/sock.h>
45#include <uapi/linux/batman_adv.h>
46
47#include "gateway_common.h"
48#include "hard-interface.h"
49#include "log.h"
50#include "netlink.h"
51#include "originator.h"
52#include "packet.h"
53#include "routing.h"
54#include "soft-interface.h"
55#include "sysfs.h"
56#include "translation-table.h"
57
58
59
60
61#define BATADV_DHCP_HTYPE_OFFSET 1
62#define BATADV_DHCP_HLEN_OFFSET 2
63
64#define BATADV_DHCP_HTYPE_ETHERNET 0x01
65
66
67
68#define BATADV_DHCP_CHADDR_OFFSET 28
69
70
71
72
73
74
75static void batadv_gw_node_release(struct kref *ref)
76{
77 struct batadv_gw_node *gw_node;
78
79 gw_node = container_of(ref, struct batadv_gw_node, refcount);
80
81 batadv_orig_node_put(gw_node->orig_node);
82 kfree_rcu(gw_node, rcu);
83}
84
85
86
87
88
89void batadv_gw_node_put(struct batadv_gw_node *gw_node)
90{
91 kref_put(&gw_node->refcount, batadv_gw_node_release);
92}
93
94struct batadv_gw_node *
95batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
96{
97 struct batadv_gw_node *gw_node;
98
99 rcu_read_lock();
100 gw_node = rcu_dereference(bat_priv->gw.curr_gw);
101 if (!gw_node)
102 goto out;
103
104 if (!kref_get_unless_zero(&gw_node->refcount))
105 gw_node = NULL;
106
107out:
108 rcu_read_unlock();
109 return gw_node;
110}
111
112struct batadv_orig_node *
113batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
114{
115 struct batadv_gw_node *gw_node;
116 struct batadv_orig_node *orig_node = NULL;
117
118 gw_node = batadv_gw_get_selected_gw_node(bat_priv);
119 if (!gw_node)
120 goto out;
121
122 rcu_read_lock();
123 orig_node = gw_node->orig_node;
124 if (!orig_node)
125 goto unlock;
126
127 if (!kref_get_unless_zero(&orig_node->refcount))
128 orig_node = NULL;
129
130unlock:
131 rcu_read_unlock();
132out:
133 if (gw_node)
134 batadv_gw_node_put(gw_node);
135 return orig_node;
136}
137
138static void batadv_gw_select(struct batadv_priv *bat_priv,
139 struct batadv_gw_node *new_gw_node)
140{
141 struct batadv_gw_node *curr_gw_node;
142
143 spin_lock_bh(&bat_priv->gw.list_lock);
144
145 if (new_gw_node)
146 kref_get(&new_gw_node->refcount);
147
148 curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
149 rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
150
151 if (curr_gw_node)
152 batadv_gw_node_put(curr_gw_node);
153
154 spin_unlock_bh(&bat_priv->gw.list_lock);
155}
156
157
158
159
160
161
162
163
164
165
166
167
168void batadv_gw_reselect(struct batadv_priv *bat_priv)
169{
170 atomic_set(&bat_priv->gw.reselect, 1);
171}
172
173
174
175
176
177
178
179
180
181void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
182{
183 struct batadv_gw_node *curr_gw;
184
185 if (atomic_read(&bat_priv->gw.mode) != BATADV_GW_MODE_CLIENT)
186 return;
187
188 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
189 if (!curr_gw)
190 return;
191
192
193
194
195 batadv_gw_select(bat_priv, NULL);
196
197
198
199
200 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL);
201
202 batadv_gw_node_put(curr_gw);
203}
204
205void batadv_gw_election(struct batadv_priv *bat_priv)
206{
207 struct batadv_gw_node *curr_gw = NULL;
208 struct batadv_gw_node *next_gw = NULL;
209 struct batadv_neigh_node *router = NULL;
210 struct batadv_neigh_ifinfo *router_ifinfo = NULL;
211 char gw_addr[18] = { '\0' };
212
213 if (atomic_read(&bat_priv->gw.mode) != BATADV_GW_MODE_CLIENT)
214 goto out;
215
216 if (!bat_priv->algo_ops->gw.get_best_gw_node)
217 goto out;
218
219 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
220
221 if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
222 goto out;
223
224
225
226
227
228 next_gw = bat_priv->algo_ops->gw.get_best_gw_node(bat_priv);
229
230 if (curr_gw == next_gw)
231 goto out;
232
233 if (next_gw) {
234 sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
235
236 router = batadv_orig_router_get(next_gw->orig_node,
237 BATADV_IF_DEFAULT);
238 if (!router) {
239 batadv_gw_reselect(bat_priv);
240 goto out;
241 }
242
243 router_ifinfo = batadv_neigh_ifinfo_get(router,
244 BATADV_IF_DEFAULT);
245 if (!router_ifinfo) {
246 batadv_gw_reselect(bat_priv);
247 goto out;
248 }
249 }
250
251 if ((curr_gw) && (!next_gw)) {
252 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
253 "Removing selected gateway - no gateway in range\n");
254 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
255 NULL);
256 } else if ((!curr_gw) && (next_gw)) {
257 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
258 "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
259 next_gw->orig_node->orig,
260 next_gw->bandwidth_down / 10,
261 next_gw->bandwidth_down % 10,
262 next_gw->bandwidth_up / 10,
263 next_gw->bandwidth_up % 10,
264 router_ifinfo->bat_iv.tq_avg);
265 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
266 gw_addr);
267 } else {
268 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
269 "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
270 next_gw->orig_node->orig,
271 next_gw->bandwidth_down / 10,
272 next_gw->bandwidth_down % 10,
273 next_gw->bandwidth_up / 10,
274 next_gw->bandwidth_up % 10,
275 router_ifinfo->bat_iv.tq_avg);
276 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
277 gw_addr);
278 }
279
280 batadv_gw_select(bat_priv, next_gw);
281
282out:
283 if (curr_gw)
284 batadv_gw_node_put(curr_gw);
285 if (next_gw)
286 batadv_gw_node_put(next_gw);
287 if (router)
288 batadv_neigh_node_put(router);
289 if (router_ifinfo)
290 batadv_neigh_ifinfo_put(router_ifinfo);
291}
292
293void batadv_gw_check_election(struct batadv_priv *bat_priv,
294 struct batadv_orig_node *orig_node)
295{
296 struct batadv_orig_node *curr_gw_orig;
297
298
299
300
301 if (!bat_priv->algo_ops->gw.is_eligible)
302 return;
303
304 curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
305 if (!curr_gw_orig)
306 goto reselect;
307
308
309 if (curr_gw_orig == orig_node)
310 goto out;
311
312 if (!bat_priv->algo_ops->gw.is_eligible(bat_priv, curr_gw_orig,
313 orig_node))
314 goto out;
315
316reselect:
317 batadv_gw_reselect(bat_priv);
318out:
319 if (curr_gw_orig)
320 batadv_orig_node_put(curr_gw_orig);
321}
322
323
324
325
326
327
328
329static void batadv_gw_node_add(struct batadv_priv *bat_priv,
330 struct batadv_orig_node *orig_node,
331 struct batadv_tvlv_gateway_data *gateway)
332{
333 struct batadv_gw_node *gw_node;
334
335 if (gateway->bandwidth_down == 0)
336 return;
337
338 gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
339 if (!gw_node)
340 return;
341
342 kref_init(&gw_node->refcount);
343 INIT_HLIST_NODE(&gw_node->list);
344 kref_get(&orig_node->refcount);
345 gw_node->orig_node = orig_node;
346 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
347 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
348
349 spin_lock_bh(&bat_priv->gw.list_lock);
350 kref_get(&gw_node->refcount);
351 hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
352 spin_unlock_bh(&bat_priv->gw.list_lock);
353
354 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
355 "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
356 orig_node->orig,
357 ntohl(gateway->bandwidth_down) / 10,
358 ntohl(gateway->bandwidth_down) % 10,
359 ntohl(gateway->bandwidth_up) / 10,
360 ntohl(gateway->bandwidth_up) % 10);
361
362
363 batadv_gw_node_put(gw_node);
364}
365
366
367
368
369
370
371
372
373struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
374 struct batadv_orig_node *orig_node)
375{
376 struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
377
378 rcu_read_lock();
379 hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) {
380 if (gw_node_tmp->orig_node != orig_node)
381 continue;
382
383 if (!kref_get_unless_zero(&gw_node_tmp->refcount))
384 continue;
385
386 gw_node = gw_node_tmp;
387 break;
388 }
389 rcu_read_unlock();
390
391 return gw_node;
392}
393
394
395
396
397
398
399
400
401void batadv_gw_node_update(struct batadv_priv *bat_priv,
402 struct batadv_orig_node *orig_node,
403 struct batadv_tvlv_gateway_data *gateway)
404{
405 struct batadv_gw_node *gw_node, *curr_gw = NULL;
406
407 gw_node = batadv_gw_node_get(bat_priv, orig_node);
408 if (!gw_node) {
409 batadv_gw_node_add(bat_priv, orig_node, gateway);
410 goto out;
411 }
412
413 if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
414 (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
415 goto out;
416
417 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
418 "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
419 orig_node->orig,
420 gw_node->bandwidth_down / 10,
421 gw_node->bandwidth_down % 10,
422 gw_node->bandwidth_up / 10,
423 gw_node->bandwidth_up % 10,
424 ntohl(gateway->bandwidth_down) / 10,
425 ntohl(gateway->bandwidth_down) % 10,
426 ntohl(gateway->bandwidth_up) / 10,
427 ntohl(gateway->bandwidth_up) % 10);
428
429 gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
430 gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
431
432 if (ntohl(gateway->bandwidth_down) == 0) {
433 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
434 "Gateway %pM removed from gateway list\n",
435 orig_node->orig);
436
437
438
439
440 spin_lock_bh(&bat_priv->gw.list_lock);
441 if (!hlist_unhashed(&gw_node->list)) {
442 hlist_del_init_rcu(&gw_node->list);
443 batadv_gw_node_put(gw_node);
444 }
445 spin_unlock_bh(&bat_priv->gw.list_lock);
446
447 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
448 if (gw_node == curr_gw)
449 batadv_gw_reselect(bat_priv);
450
451 if (curr_gw)
452 batadv_gw_node_put(curr_gw);
453 }
454
455out:
456 if (gw_node)
457 batadv_gw_node_put(gw_node);
458}
459
460void batadv_gw_node_delete(struct batadv_priv *bat_priv,
461 struct batadv_orig_node *orig_node)
462{
463 struct batadv_tvlv_gateway_data gateway;
464
465 gateway.bandwidth_down = 0;
466 gateway.bandwidth_up = 0;
467
468 batadv_gw_node_update(bat_priv, orig_node, &gateway);
469}
470
471void batadv_gw_node_free(struct batadv_priv *bat_priv)
472{
473 struct batadv_gw_node *gw_node;
474 struct hlist_node *node_tmp;
475
476 spin_lock_bh(&bat_priv->gw.list_lock);
477 hlist_for_each_entry_safe(gw_node, node_tmp,
478 &bat_priv->gw.list, list) {
479 hlist_del_init_rcu(&gw_node->list);
480 batadv_gw_node_put(gw_node);
481 }
482 spin_unlock_bh(&bat_priv->gw.list_lock);
483}
484
485#ifdef CONFIG_BATMAN_ADV_DEBUGFS
486int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
487{
488 struct net_device *net_dev = (struct net_device *)seq->private;
489 struct batadv_priv *bat_priv = netdev_priv(net_dev);
490 struct batadv_hard_iface *primary_if;
491
492 primary_if = batadv_seq_print_text_primary_if_get(seq);
493 if (!primary_if)
494 return 0;
495
496 seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
497 BATADV_SOURCE_VERSION, primary_if->net_dev->name,
498 primary_if->net_dev->dev_addr, net_dev->name,
499 bat_priv->algo_ops->name);
500
501 batadv_hardif_put(primary_if);
502
503 if (!bat_priv->algo_ops->gw.print) {
504 seq_puts(seq,
505 "No printing function for this routing protocol\n");
506 return 0;
507 }
508
509 bat_priv->algo_ops->gw.print(bat_priv, seq);
510
511 return 0;
512}
513#endif
514
515
516
517
518
519
520
521
522int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
523{
524 struct batadv_hard_iface *primary_if = NULL;
525 struct net *net = sock_net(cb->skb->sk);
526 struct net_device *soft_iface;
527 struct batadv_priv *bat_priv;
528 int ifindex;
529 int ret;
530
531 ifindex = batadv_netlink_get_ifindex(cb->nlh,
532 BATADV_ATTR_MESH_IFINDEX);
533 if (!ifindex)
534 return -EINVAL;
535
536 soft_iface = dev_get_by_index(net, ifindex);
537 if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
538 ret = -ENODEV;
539 goto out;
540 }
541
542 bat_priv = netdev_priv(soft_iface);
543
544 primary_if = batadv_primary_if_get_selected(bat_priv);
545 if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
546 ret = -ENOENT;
547 goto out;
548 }
549
550 if (!bat_priv->algo_ops->gw.dump) {
551 ret = -EOPNOTSUPP;
552 goto out;
553 }
554
555 bat_priv->algo_ops->gw.dump(msg, cb, bat_priv);
556
557 ret = msg->len;
558
559out:
560 if (primary_if)
561 batadv_hardif_put(primary_if);
562 if (soft_iface)
563 dev_put(soft_iface);
564
565 return ret;
566}
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583enum batadv_dhcp_recipient
584batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
585 u8 *chaddr)
586{
587 enum batadv_dhcp_recipient ret = BATADV_DHCP_NO;
588 struct ethhdr *ethhdr;
589 struct iphdr *iphdr;
590 struct ipv6hdr *ipv6hdr;
591 struct udphdr *udphdr;
592 struct vlan_ethhdr *vhdr;
593 int chaddr_offset;
594 __be16 proto;
595 u8 *p;
596
597
598 if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
599 return BATADV_DHCP_NO;
600
601 ethhdr = eth_hdr(skb);
602 proto = ethhdr->h_proto;
603 *header_len += ETH_HLEN;
604
605
606 if (proto == htons(ETH_P_8021Q)) {
607 if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
608 return BATADV_DHCP_NO;
609
610 vhdr = vlan_eth_hdr(skb);
611 proto = vhdr->h_vlan_encapsulated_proto;
612 *header_len += VLAN_HLEN;
613 }
614
615
616 switch (proto) {
617 case htons(ETH_P_IP):
618 if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
619 return BATADV_DHCP_NO;
620
621 iphdr = (struct iphdr *)(skb->data + *header_len);
622 *header_len += iphdr->ihl * 4;
623
624
625 if (iphdr->protocol != IPPROTO_UDP)
626 return BATADV_DHCP_NO;
627
628 break;
629 case htons(ETH_P_IPV6):
630 if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
631 return BATADV_DHCP_NO;
632
633 ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
634 *header_len += sizeof(*ipv6hdr);
635
636
637 if (ipv6hdr->nexthdr != IPPROTO_UDP)
638 return BATADV_DHCP_NO;
639
640 break;
641 default:
642 return BATADV_DHCP_NO;
643 }
644
645 if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
646 return BATADV_DHCP_NO;
647
648 udphdr = (struct udphdr *)(skb->data + *header_len);
649 *header_len += sizeof(*udphdr);
650
651
652 switch (proto) {
653 case htons(ETH_P_IP):
654 if (udphdr->dest == htons(67))
655 ret = BATADV_DHCP_TO_SERVER;
656 else if (udphdr->source == htons(67))
657 ret = BATADV_DHCP_TO_CLIENT;
658 break;
659 case htons(ETH_P_IPV6):
660 if (udphdr->dest == htons(547))
661 ret = BATADV_DHCP_TO_SERVER;
662 else if (udphdr->source == htons(547))
663 ret = BATADV_DHCP_TO_CLIENT;
664 break;
665 }
666
667 chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
668
669 if (ret == BATADV_DHCP_TO_CLIENT &&
670 pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) {
671
672 p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
673 if (*p != BATADV_DHCP_HTYPE_ETHERNET)
674 return BATADV_DHCP_NO;
675
676
677 p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET;
678 if (*p != ETH_ALEN)
679 return BATADV_DHCP_NO;
680
681 ether_addr_copy(chaddr, skb->data + chaddr_offset);
682 }
683
684 return ret;
685}
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
703 struct sk_buff *skb)
704{
705 struct batadv_neigh_node *neigh_curr = NULL;
706 struct batadv_neigh_node *neigh_old = NULL;
707 struct batadv_orig_node *orig_dst_node = NULL;
708 struct batadv_gw_node *gw_node = NULL;
709 struct batadv_gw_node *curr_gw = NULL;
710 struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
711 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
712 bool out_of_range = false;
713 u8 curr_tq_avg;
714 unsigned short vid;
715
716 vid = batadv_get_vid(skb, 0);
717
718 orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
719 ethhdr->h_dest, vid);
720 if (!orig_dst_node)
721 goto out;
722
723 gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
724 if (!gw_node)
725 goto out;
726
727 switch (atomic_read(&bat_priv->gw.mode)) {
728 case BATADV_GW_MODE_SERVER:
729
730
731
732 curr_tq_avg = BATADV_TQ_MAX_VALUE;
733 break;
734 case BATADV_GW_MODE_CLIENT:
735 curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
736 if (!curr_gw)
737 goto out;
738
739
740 if (curr_gw->orig_node == orig_dst_node)
741 goto out;
742
743
744
745
746
747 neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
748 NULL);
749 if (!neigh_curr)
750 goto out;
751
752 curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr,
753 BATADV_IF_DEFAULT);
754 if (!curr_ifinfo)
755 goto out;
756
757 curr_tq_avg = curr_ifinfo->bat_iv.tq_avg;
758 batadv_neigh_ifinfo_put(curr_ifinfo);
759
760 break;
761 case BATADV_GW_MODE_OFF:
762 default:
763 goto out;
764 }
765
766 neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
767 if (!neigh_old)
768 goto out;
769
770 old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT);
771 if (!old_ifinfo)
772 goto out;
773
774 if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD)
775 out_of_range = true;
776 batadv_neigh_ifinfo_put(old_ifinfo);
777
778out:
779 if (orig_dst_node)
780 batadv_orig_node_put(orig_dst_node);
781 if (curr_gw)
782 batadv_gw_node_put(curr_gw);
783 if (gw_node)
784 batadv_gw_node_put(gw_node);
785 if (neigh_old)
786 batadv_neigh_node_put(neigh_old);
787 if (neigh_curr)
788 batadv_neigh_node_put(neigh_curr);
789 return out_of_range;
790}
791