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TOMOYO Linux Cross Reference
Linux/net/batman-adv/routing.c

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  1 // SPDX-License-Identifier: GPL-2.0
  2 /* Copyright (C) 2007-2018  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, see <http://www.gnu.org/licenses/>.
 17  */
 18 
 19 #include "routing.h"
 20 #include "main.h"
 21 
 22 #include <linux/atomic.h>
 23 #include <linux/byteorder/generic.h>
 24 #include <linux/compiler.h>
 25 #include <linux/errno.h>
 26 #include <linux/etherdevice.h>
 27 #include <linux/if_ether.h>
 28 #include <linux/jiffies.h>
 29 #include <linux/kref.h>
 30 #include <linux/netdevice.h>
 31 #include <linux/printk.h>
 32 #include <linux/rculist.h>
 33 #include <linux/rcupdate.h>
 34 #include <linux/skbuff.h>
 35 #include <linux/spinlock.h>
 36 #include <linux/stddef.h>
 37 #include <uapi/linux/batadv_packet.h>
 38 
 39 #include "bitarray.h"
 40 #include "bridge_loop_avoidance.h"
 41 #include "distributed-arp-table.h"
 42 #include "fragmentation.h"
 43 #include "hard-interface.h"
 44 #include "icmp_socket.h"
 45 #include "log.h"
 46 #include "network-coding.h"
 47 #include "originator.h"
 48 #include "send.h"
 49 #include "soft-interface.h"
 50 #include "tp_meter.h"
 51 #include "translation-table.h"
 52 #include "tvlv.h"
 53 
 54 static int batadv_route_unicast_packet(struct sk_buff *skb,
 55                                        struct batadv_hard_iface *recv_if);
 56 
 57 /**
 58  * _batadv_update_route() - set the router for this originator
 59  * @bat_priv: the bat priv with all the soft interface information
 60  * @orig_node: orig node which is to be configured
 61  * @recv_if: the receive interface for which this route is set
 62  * @neigh_node: neighbor which should be the next router
 63  *
 64  * This function does not perform any error checks
 65  */
 66 static void _batadv_update_route(struct batadv_priv *bat_priv,
 67                                  struct batadv_orig_node *orig_node,
 68                                  struct batadv_hard_iface *recv_if,
 69                                  struct batadv_neigh_node *neigh_node)
 70 {
 71         struct batadv_orig_ifinfo *orig_ifinfo;
 72         struct batadv_neigh_node *curr_router;
 73 
 74         orig_ifinfo = batadv_orig_ifinfo_get(orig_node, recv_if);
 75         if (!orig_ifinfo)
 76                 return;
 77 
 78         spin_lock_bh(&orig_node->neigh_list_lock);
 79         /* curr_router used earlier may not be the current orig_ifinfo->router
 80          * anymore because it was dereferenced outside of the neigh_list_lock
 81          * protected region. After the new best neighbor has replace the current
 82          * best neighbor the reference counter needs to decrease. Consequently,
 83          * the code needs to ensure the curr_router variable contains a pointer
 84          * to the replaced best neighbor.
 85          */
 86         curr_router = rcu_dereference_protected(orig_ifinfo->router, true);
 87 
 88         /* increase refcount of new best neighbor */
 89         if (neigh_node)
 90                 kref_get(&neigh_node->refcount);
 91 
 92         rcu_assign_pointer(orig_ifinfo->router, neigh_node);
 93         spin_unlock_bh(&orig_node->neigh_list_lock);
 94         batadv_orig_ifinfo_put(orig_ifinfo);
 95 
 96         /* route deleted */
 97         if (curr_router && !neigh_node) {
 98                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
 99                            "Deleting route towards: %pM\n", orig_node->orig);
100                 batadv_tt_global_del_orig(bat_priv, orig_node, -1,
101                                           "Deleted route towards originator");
102 
103         /* route added */
104         } else if (!curr_router && neigh_node) {
105                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
106                            "Adding route towards: %pM (via %pM)\n",
107                            orig_node->orig, neigh_node->addr);
108         /* route changed */
109         } else if (neigh_node && curr_router) {
110                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
111                            "Changing route towards: %pM (now via %pM - was via %pM)\n",
112                            orig_node->orig, neigh_node->addr,
113                            curr_router->addr);
114         }
115 
116         /* decrease refcount of previous best neighbor */
117         if (curr_router)
118                 batadv_neigh_node_put(curr_router);
119 }
120 
121 /**
122  * batadv_update_route() - set the router for this originator
123  * @bat_priv: the bat priv with all the soft interface information
124  * @orig_node: orig node which is to be configured
125  * @recv_if: the receive interface for which this route is set
126  * @neigh_node: neighbor which should be the next router
127  */
128 void batadv_update_route(struct batadv_priv *bat_priv,
129                          struct batadv_orig_node *orig_node,
130                          struct batadv_hard_iface *recv_if,
131                          struct batadv_neigh_node *neigh_node)
132 {
133         struct batadv_neigh_node *router = NULL;
134 
135         if (!orig_node)
136                 goto out;
137 
138         router = batadv_orig_router_get(orig_node, recv_if);
139 
140         if (router != neigh_node)
141                 _batadv_update_route(bat_priv, orig_node, recv_if, neigh_node);
142 
143 out:
144         if (router)
145                 batadv_neigh_node_put(router);
146 }
147 
148 /**
149  * batadv_window_protected() - checks whether the host restarted and is in the
150  *  protection time.
151  * @bat_priv: the bat priv with all the soft interface information
152  * @seq_num_diff: difference between the current/received sequence number and
153  *  the last sequence number
154  * @seq_old_max_diff: maximum age of sequence number not considered as restart
155  * @last_reset: jiffies timestamp of the last reset, will be updated when reset
156  *  is detected
157  * @protection_started: is set to true if the protection window was started,
158  *   doesn't change otherwise.
159  *
160  * Return:
161  *  false if the packet is to be accepted.
162  *  true if the packet is to be ignored.
163  */
164 bool batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
165                              s32 seq_old_max_diff, unsigned long *last_reset,
166                              bool *protection_started)
167 {
168         if (seq_num_diff <= -seq_old_max_diff ||
169             seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
170                 if (!batadv_has_timed_out(*last_reset,
171                                           BATADV_RESET_PROTECTION_MS))
172                         return true;
173 
174                 *last_reset = jiffies;
175                 if (protection_started)
176                         *protection_started = true;
177                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
178                            "old packet received, start protection\n");
179         }
180 
181         return false;
182 }
183 
184 /**
185  * batadv_check_management_packet() - Check preconditions for management packets
186  * @skb: incoming packet buffer
187  * @hard_iface: incoming hard interface
188  * @header_len: minimal header length of packet type
189  *
190  * Return: true when management preconditions are met, false otherwise
191  */
192 bool batadv_check_management_packet(struct sk_buff *skb,
193                                     struct batadv_hard_iface *hard_iface,
194                                     int header_len)
195 {
196         struct ethhdr *ethhdr;
197 
198         /* drop packet if it has not necessary minimum size */
199         if (unlikely(!pskb_may_pull(skb, header_len)))
200                 return false;
201 
202         ethhdr = eth_hdr(skb);
203 
204         /* packet with broadcast indication but unicast recipient */
205         if (!is_broadcast_ether_addr(ethhdr->h_dest))
206                 return false;
207 
208         /* packet with invalid sender address */
209         if (!is_valid_ether_addr(ethhdr->h_source))
210                 return false;
211 
212         /* create a copy of the skb, if needed, to modify it. */
213         if (skb_cow(skb, 0) < 0)
214                 return false;
215 
216         /* keep skb linear */
217         if (skb_linearize(skb) < 0)
218                 return false;
219 
220         return true;
221 }
222 
223 /**
224  * batadv_recv_my_icmp_packet() - receive an icmp packet locally
225  * @bat_priv: the bat priv with all the soft interface information
226  * @skb: icmp packet to process
227  *
228  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
229  * otherwise.
230  */
231 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
232                                       struct sk_buff *skb)
233 {
234         struct batadv_hard_iface *primary_if = NULL;
235         struct batadv_orig_node *orig_node = NULL;
236         struct batadv_icmp_header *icmph;
237         int res, ret = NET_RX_DROP;
238 
239         icmph = (struct batadv_icmp_header *)skb->data;
240 
241         switch (icmph->msg_type) {
242         case BATADV_ECHO_REPLY:
243         case BATADV_DESTINATION_UNREACHABLE:
244         case BATADV_TTL_EXCEEDED:
245                 /* receive the packet */
246                 if (skb_linearize(skb) < 0)
247                         break;
248 
249                 batadv_socket_receive_packet(icmph, skb->len);
250                 break;
251         case BATADV_ECHO_REQUEST:
252                 /* answer echo request (ping) */
253                 primary_if = batadv_primary_if_get_selected(bat_priv);
254                 if (!primary_if)
255                         goto out;
256 
257                 /* get routing information */
258                 orig_node = batadv_orig_hash_find(bat_priv, icmph->orig);
259                 if (!orig_node)
260                         goto out;
261 
262                 /* create a copy of the skb, if needed, to modify it. */
263                 if (skb_cow(skb, ETH_HLEN) < 0)
264                         goto out;
265 
266                 icmph = (struct batadv_icmp_header *)skb->data;
267 
268                 ether_addr_copy(icmph->dst, icmph->orig);
269                 ether_addr_copy(icmph->orig, primary_if->net_dev->dev_addr);
270                 icmph->msg_type = BATADV_ECHO_REPLY;
271                 icmph->ttl = BATADV_TTL;
272 
273                 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
274                 if (res == NET_XMIT_SUCCESS)
275                         ret = NET_RX_SUCCESS;
276 
277                 /* skb was consumed */
278                 skb = NULL;
279                 break;
280         case BATADV_TP:
281                 if (!pskb_may_pull(skb, sizeof(struct batadv_icmp_tp_packet)))
282                         goto out;
283 
284                 batadv_tp_meter_recv(bat_priv, skb);
285                 ret = NET_RX_SUCCESS;
286                 /* skb was consumed */
287                 skb = NULL;
288                 goto out;
289         default:
290                 /* drop unknown type */
291                 goto out;
292         }
293 out:
294         if (primary_if)
295                 batadv_hardif_put(primary_if);
296         if (orig_node)
297                 batadv_orig_node_put(orig_node);
298 
299         kfree_skb(skb);
300 
301         return ret;
302 }
303 
304 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
305                                          struct sk_buff *skb)
306 {
307         struct batadv_hard_iface *primary_if = NULL;
308         struct batadv_orig_node *orig_node = NULL;
309         struct batadv_icmp_packet *icmp_packet;
310         int res, ret = NET_RX_DROP;
311 
312         icmp_packet = (struct batadv_icmp_packet *)skb->data;
313 
314         /* send TTL exceeded if packet is an echo request (traceroute) */
315         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
316                 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
317                          icmp_packet->orig, icmp_packet->dst);
318                 goto out;
319         }
320 
321         primary_if = batadv_primary_if_get_selected(bat_priv);
322         if (!primary_if)
323                 goto out;
324 
325         /* get routing information */
326         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
327         if (!orig_node)
328                 goto out;
329 
330         /* create a copy of the skb, if needed, to modify it. */
331         if (skb_cow(skb, ETH_HLEN) < 0)
332                 goto out;
333 
334         icmp_packet = (struct batadv_icmp_packet *)skb->data;
335 
336         ether_addr_copy(icmp_packet->dst, icmp_packet->orig);
337         ether_addr_copy(icmp_packet->orig, primary_if->net_dev->dev_addr);
338         icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
339         icmp_packet->ttl = BATADV_TTL;
340 
341         res = batadv_send_skb_to_orig(skb, orig_node, NULL);
342         if (res == NET_RX_SUCCESS)
343                 ret = NET_XMIT_SUCCESS;
344 
345         /* skb was consumed */
346         skb = NULL;
347 
348 out:
349         if (primary_if)
350                 batadv_hardif_put(primary_if);
351         if (orig_node)
352                 batadv_orig_node_put(orig_node);
353 
354         kfree_skb(skb);
355 
356         return ret;
357 }
358 
359 /**
360  * batadv_recv_icmp_packet() - Process incoming icmp packet
361  * @skb: incoming packet buffer
362  * @recv_if: incoming hard interface
363  *
364  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
365  */
366 int batadv_recv_icmp_packet(struct sk_buff *skb,
367                             struct batadv_hard_iface *recv_if)
368 {
369         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
370         struct batadv_icmp_header *icmph;
371         struct batadv_icmp_packet_rr *icmp_packet_rr;
372         struct ethhdr *ethhdr;
373         struct batadv_orig_node *orig_node = NULL;
374         int hdr_size = sizeof(struct batadv_icmp_header);
375         int res, ret = NET_RX_DROP;
376 
377         /* drop packet if it has not necessary minimum size */
378         if (unlikely(!pskb_may_pull(skb, hdr_size)))
379                 goto free_skb;
380 
381         ethhdr = eth_hdr(skb);
382 
383         /* packet with unicast indication but non-unicast recipient */
384         if (!is_valid_ether_addr(ethhdr->h_dest))
385                 goto free_skb;
386 
387         /* packet with broadcast/multicast sender address */
388         if (is_multicast_ether_addr(ethhdr->h_source))
389                 goto free_skb;
390 
391         /* not for me */
392         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
393                 goto free_skb;
394 
395         icmph = (struct batadv_icmp_header *)skb->data;
396 
397         /* add record route information if not full */
398         if ((icmph->msg_type == BATADV_ECHO_REPLY ||
399              icmph->msg_type == BATADV_ECHO_REQUEST) &&
400             skb->len >= sizeof(struct batadv_icmp_packet_rr)) {
401                 if (skb_linearize(skb) < 0)
402                         goto free_skb;
403 
404                 /* create a copy of the skb, if needed, to modify it. */
405                 if (skb_cow(skb, ETH_HLEN) < 0)
406                         goto free_skb;
407 
408                 ethhdr = eth_hdr(skb);
409                 icmph = (struct batadv_icmp_header *)skb->data;
410                 icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmph;
411                 if (icmp_packet_rr->rr_cur >= BATADV_RR_LEN)
412                         goto free_skb;
413 
414                 ether_addr_copy(icmp_packet_rr->rr[icmp_packet_rr->rr_cur],
415                                 ethhdr->h_dest);
416                 icmp_packet_rr->rr_cur++;
417         }
418 
419         /* packet for me */
420         if (batadv_is_my_mac(bat_priv, icmph->dst))
421                 return batadv_recv_my_icmp_packet(bat_priv, skb);
422 
423         /* TTL exceeded */
424         if (icmph->ttl < 2)
425                 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
426 
427         /* get routing information */
428         orig_node = batadv_orig_hash_find(bat_priv, icmph->dst);
429         if (!orig_node)
430                 goto free_skb;
431 
432         /* create a copy of the skb, if needed, to modify it. */
433         if (skb_cow(skb, ETH_HLEN) < 0)
434                 goto put_orig_node;
435 
436         icmph = (struct batadv_icmp_header *)skb->data;
437 
438         /* decrement ttl */
439         icmph->ttl--;
440 
441         /* route it */
442         res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
443         if (res == NET_XMIT_SUCCESS)
444                 ret = NET_RX_SUCCESS;
445 
446         /* skb was consumed */
447         skb = NULL;
448 
449 put_orig_node:
450         if (orig_node)
451                 batadv_orig_node_put(orig_node);
452 free_skb:
453         kfree_skb(skb);
454 
455         return ret;
456 }
457 
458 /**
459  * batadv_check_unicast_packet() - Check for malformed unicast packets
460  * @bat_priv: the bat priv with all the soft interface information
461  * @skb: packet to check
462  * @hdr_size: size of header to pull
463  *
464  * Check for short header and bad addresses in given packet.
465  *
466  * Return: negative value when check fails and 0 otherwise. The negative value
467  * depends on the reason: -ENODATA for bad header, -EBADR for broadcast
468  * destination or source, and -EREMOTE for non-local (other host) destination.
469  */
470 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
471                                        struct sk_buff *skb, int hdr_size)
472 {
473         struct ethhdr *ethhdr;
474 
475         /* drop packet if it has not necessary minimum size */
476         if (unlikely(!pskb_may_pull(skb, hdr_size)))
477                 return -ENODATA;
478 
479         ethhdr = eth_hdr(skb);
480 
481         /* packet with unicast indication but non-unicast recipient */
482         if (!is_valid_ether_addr(ethhdr->h_dest))
483                 return -EBADR;
484 
485         /* packet with broadcast/multicast sender address */
486         if (is_multicast_ether_addr(ethhdr->h_source))
487                 return -EBADR;
488 
489         /* not for me */
490         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
491                 return -EREMOTE;
492 
493         return 0;
494 }
495 
496 /**
497  * batadv_last_bonding_get() - Get last_bonding_candidate of orig_node
498  * @orig_node: originator node whose last bonding candidate should be retrieved
499  *
500  * Return: last bonding candidate of router or NULL if not found
501  *
502  * The object is returned with refcounter increased by 1.
503  */
504 static struct batadv_orig_ifinfo *
505 batadv_last_bonding_get(struct batadv_orig_node *orig_node)
506 {
507         struct batadv_orig_ifinfo *last_bonding_candidate;
508 
509         spin_lock_bh(&orig_node->neigh_list_lock);
510         last_bonding_candidate = orig_node->last_bonding_candidate;
511 
512         if (last_bonding_candidate)
513                 kref_get(&last_bonding_candidate->refcount);
514         spin_unlock_bh(&orig_node->neigh_list_lock);
515 
516         return last_bonding_candidate;
517 }
518 
519 /**
520  * batadv_last_bonding_replace() - Replace last_bonding_candidate of orig_node
521  * @orig_node: originator node whose bonding candidates should be replaced
522  * @new_candidate: new bonding candidate or NULL
523  */
524 static void
525 batadv_last_bonding_replace(struct batadv_orig_node *orig_node,
526                             struct batadv_orig_ifinfo *new_candidate)
527 {
528         struct batadv_orig_ifinfo *old_candidate;
529 
530         spin_lock_bh(&orig_node->neigh_list_lock);
531         old_candidate = orig_node->last_bonding_candidate;
532 
533         if (new_candidate)
534                 kref_get(&new_candidate->refcount);
535         orig_node->last_bonding_candidate = new_candidate;
536         spin_unlock_bh(&orig_node->neigh_list_lock);
537 
538         if (old_candidate)
539                 batadv_orig_ifinfo_put(old_candidate);
540 }
541 
542 /**
543  * batadv_find_router() - find a suitable router for this originator
544  * @bat_priv: the bat priv with all the soft interface information
545  * @orig_node: the destination node
546  * @recv_if: pointer to interface this packet was received on
547  *
548  * Return: the router which should be used for this orig_node on
549  * this interface, or NULL if not available.
550  */
551 struct batadv_neigh_node *
552 batadv_find_router(struct batadv_priv *bat_priv,
553                    struct batadv_orig_node *orig_node,
554                    struct batadv_hard_iface *recv_if)
555 {
556         struct batadv_algo_ops *bao = bat_priv->algo_ops;
557         struct batadv_neigh_node *first_candidate_router = NULL;
558         struct batadv_neigh_node *next_candidate_router = NULL;
559         struct batadv_neigh_node *router, *cand_router = NULL;
560         struct batadv_neigh_node *last_cand_router = NULL;
561         struct batadv_orig_ifinfo *cand, *first_candidate = NULL;
562         struct batadv_orig_ifinfo *next_candidate = NULL;
563         struct batadv_orig_ifinfo *last_candidate;
564         bool last_candidate_found = false;
565 
566         if (!orig_node)
567                 return NULL;
568 
569         router = batadv_orig_router_get(orig_node, recv_if);
570 
571         if (!router)
572                 return router;
573 
574         /* only consider bonding for recv_if == BATADV_IF_DEFAULT (first hop)
575          * and if activated.
576          */
577         if (!(recv_if == BATADV_IF_DEFAULT && atomic_read(&bat_priv->bonding)))
578                 return router;
579 
580         /* bonding: loop through the list of possible routers found
581          * for the various outgoing interfaces and find a candidate after
582          * the last chosen bonding candidate (next_candidate). If no such
583          * router is found, use the first candidate found (the previously
584          * chosen bonding candidate might have been the last one in the list).
585          * If this can't be found either, return the previously chosen
586          * router - obviously there are no other candidates.
587          */
588         rcu_read_lock();
589         last_candidate = batadv_last_bonding_get(orig_node);
590         if (last_candidate)
591                 last_cand_router = rcu_dereference(last_candidate->router);
592 
593         hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) {
594                 /* acquire some structures and references ... */
595                 if (!kref_get_unless_zero(&cand->refcount))
596                         continue;
597 
598                 cand_router = rcu_dereference(cand->router);
599                 if (!cand_router)
600                         goto next;
601 
602                 if (!kref_get_unless_zero(&cand_router->refcount)) {
603                         cand_router = NULL;
604                         goto next;
605                 }
606 
607                 /* alternative candidate should be good enough to be
608                  * considered
609                  */
610                 if (!bao->neigh.is_similar_or_better(cand_router,
611                                                      cand->if_outgoing, router,
612                                                      recv_if))
613                         goto next;
614 
615                 /* don't use the same router twice */
616                 if (last_cand_router == cand_router)
617                         goto next;
618 
619                 /* mark the first possible candidate */
620                 if (!first_candidate) {
621                         kref_get(&cand_router->refcount);
622                         kref_get(&cand->refcount);
623                         first_candidate = cand;
624                         first_candidate_router = cand_router;
625                 }
626 
627                 /* check if the loop has already passed the previously selected
628                  * candidate ... this function should select the next candidate
629                  * AFTER the previously used bonding candidate.
630                  */
631                 if (!last_candidate || last_candidate_found) {
632                         next_candidate = cand;
633                         next_candidate_router = cand_router;
634                         break;
635                 }
636 
637                 if (last_candidate == cand)
638                         last_candidate_found = true;
639 next:
640                 /* free references */
641                 if (cand_router) {
642                         batadv_neigh_node_put(cand_router);
643                         cand_router = NULL;
644                 }
645                 batadv_orig_ifinfo_put(cand);
646         }
647         rcu_read_unlock();
648 
649         /* After finding candidates, handle the three cases:
650          * 1) there is a next candidate, use that
651          * 2) there is no next candidate, use the first of the list
652          * 3) there is no candidate at all, return the default router
653          */
654         if (next_candidate) {
655                 batadv_neigh_node_put(router);
656 
657                 kref_get(&next_candidate_router->refcount);
658                 router = next_candidate_router;
659                 batadv_last_bonding_replace(orig_node, next_candidate);
660         } else if (first_candidate) {
661                 batadv_neigh_node_put(router);
662 
663                 kref_get(&first_candidate_router->refcount);
664                 router = first_candidate_router;
665                 batadv_last_bonding_replace(orig_node, first_candidate);
666         } else {
667                 batadv_last_bonding_replace(orig_node, NULL);
668         }
669 
670         /* cleanup of candidates */
671         if (first_candidate) {
672                 batadv_neigh_node_put(first_candidate_router);
673                 batadv_orig_ifinfo_put(first_candidate);
674         }
675 
676         if (next_candidate) {
677                 batadv_neigh_node_put(next_candidate_router);
678                 batadv_orig_ifinfo_put(next_candidate);
679         }
680 
681         if (last_candidate)
682                 batadv_orig_ifinfo_put(last_candidate);
683 
684         return router;
685 }
686 
687 static int batadv_route_unicast_packet(struct sk_buff *skb,
688                                        struct batadv_hard_iface *recv_if)
689 {
690         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
691         struct batadv_orig_node *orig_node = NULL;
692         struct batadv_unicast_packet *unicast_packet;
693         struct ethhdr *ethhdr = eth_hdr(skb);
694         int res, hdr_len, ret = NET_RX_DROP;
695         unsigned int len;
696 
697         unicast_packet = (struct batadv_unicast_packet *)skb->data;
698 
699         /* TTL exceeded */
700         if (unicast_packet->ttl < 2) {
701                 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
702                          ethhdr->h_source, unicast_packet->dest);
703                 goto free_skb;
704         }
705 
706         /* get routing information */
707         orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
708 
709         if (!orig_node)
710                 goto free_skb;
711 
712         /* create a copy of the skb, if needed, to modify it. */
713         if (skb_cow(skb, ETH_HLEN) < 0)
714                 goto put_orig_node;
715 
716         /* decrement ttl */
717         unicast_packet = (struct batadv_unicast_packet *)skb->data;
718         unicast_packet->ttl--;
719 
720         switch (unicast_packet->packet_type) {
721         case BATADV_UNICAST_4ADDR:
722                 hdr_len = sizeof(struct batadv_unicast_4addr_packet);
723                 break;
724         case BATADV_UNICAST:
725                 hdr_len = sizeof(struct batadv_unicast_packet);
726                 break;
727         default:
728                 /* other packet types not supported - yet */
729                 hdr_len = -1;
730                 break;
731         }
732 
733         if (hdr_len > 0)
734                 batadv_skb_set_priority(skb, hdr_len);
735 
736         len = skb->len;
737         res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
738 
739         /* translate transmit result into receive result */
740         if (res == NET_XMIT_SUCCESS) {
741                 ret = NET_RX_SUCCESS;
742                 /* skb was transmitted and consumed */
743                 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
744                 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
745                                    len + ETH_HLEN);
746         }
747 
748         /* skb was consumed */
749         skb = NULL;
750 
751 put_orig_node:
752         batadv_orig_node_put(orig_node);
753 free_skb:
754         kfree_skb(skb);
755 
756         return ret;
757 }
758 
759 /**
760  * batadv_reroute_unicast_packet() - update the unicast header for re-routing
761  * @bat_priv: the bat priv with all the soft interface information
762  * @skb: unicast packet to process
763  * @unicast_packet: the unicast header to be updated
764  * @dst_addr: the payload destination
765  * @vid: VLAN identifier
766  *
767  * Search the translation table for dst_addr and update the unicast header with
768  * the new corresponding information (originator address where the destination
769  * client currently is and its known TTVN)
770  *
771  * Return: true if the packet header has been updated, false otherwise
772  */
773 static bool
774 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv, struct sk_buff *skb,
775                               struct batadv_unicast_packet *unicast_packet,
776                               u8 *dst_addr, unsigned short vid)
777 {
778         struct batadv_orig_node *orig_node = NULL;
779         struct batadv_hard_iface *primary_if = NULL;
780         bool ret = false;
781         u8 *orig_addr, orig_ttvn;
782 
783         if (batadv_is_my_client(bat_priv, dst_addr, vid)) {
784                 primary_if = batadv_primary_if_get_selected(bat_priv);
785                 if (!primary_if)
786                         goto out;
787                 orig_addr = primary_if->net_dev->dev_addr;
788                 orig_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
789         } else {
790                 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr,
791                                                      vid);
792                 if (!orig_node)
793                         goto out;
794 
795                 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
796                         goto out;
797 
798                 orig_addr = orig_node->orig;
799                 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
800         }
801 
802         /* update the packet header */
803         skb_postpull_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
804         ether_addr_copy(unicast_packet->dest, orig_addr);
805         unicast_packet->ttvn = orig_ttvn;
806         skb_postpush_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
807 
808         ret = true;
809 out:
810         if (primary_if)
811                 batadv_hardif_put(primary_if);
812         if (orig_node)
813                 batadv_orig_node_put(orig_node);
814 
815         return ret;
816 }
817 
818 static bool batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
819                                       struct sk_buff *skb, int hdr_len)
820 {
821         struct batadv_unicast_packet *unicast_packet;
822         struct batadv_hard_iface *primary_if;
823         struct batadv_orig_node *orig_node;
824         u8 curr_ttvn, old_ttvn;
825         struct ethhdr *ethhdr;
826         unsigned short vid;
827         int is_old_ttvn;
828 
829         /* check if there is enough data before accessing it */
830         if (!pskb_may_pull(skb, hdr_len + ETH_HLEN))
831                 return false;
832 
833         /* create a copy of the skb (in case of for re-routing) to modify it. */
834         if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
835                 return false;
836 
837         unicast_packet = (struct batadv_unicast_packet *)skb->data;
838         vid = batadv_get_vid(skb, hdr_len);
839         ethhdr = (struct ethhdr *)(skb->data + hdr_len);
840 
841         /* check if the destination client was served by this node and it is now
842          * roaming. In this case, it means that the node has got a ROAM_ADV
843          * message and that it knows the new destination in the mesh to re-route
844          * the packet to
845          */
846         if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest, vid)) {
847                 if (batadv_reroute_unicast_packet(bat_priv, skb, unicast_packet,
848                                                   ethhdr->h_dest, vid))
849                         batadv_dbg_ratelimited(BATADV_DBG_TT,
850                                                bat_priv,
851                                                "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
852                                                unicast_packet->dest,
853                                                ethhdr->h_dest);
854                 /* at this point the mesh destination should have been
855                  * substituted with the originator address found in the global
856                  * table. If not, let the packet go untouched anyway because
857                  * there is nothing the node can do
858                  */
859                 return true;
860         }
861 
862         /* retrieve the TTVN known by this node for the packet destination. This
863          * value is used later to check if the node which sent (or re-routed
864          * last time) the packet had an updated information or not
865          */
866         curr_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
867         if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
868                 orig_node = batadv_orig_hash_find(bat_priv,
869                                                   unicast_packet->dest);
870                 /* if it is not possible to find the orig_node representing the
871                  * destination, the packet can immediately be dropped as it will
872                  * not be possible to deliver it
873                  */
874                 if (!orig_node)
875                         return false;
876 
877                 curr_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
878                 batadv_orig_node_put(orig_node);
879         }
880 
881         /* check if the TTVN contained in the packet is fresher than what the
882          * node knows
883          */
884         is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
885         if (!is_old_ttvn)
886                 return true;
887 
888         old_ttvn = unicast_packet->ttvn;
889         /* the packet was forged based on outdated network information. Its
890          * destination can possibly be updated and forwarded towards the new
891          * target host
892          */
893         if (batadv_reroute_unicast_packet(bat_priv, skb, unicast_packet,
894                                           ethhdr->h_dest, vid)) {
895                 batadv_dbg_ratelimited(BATADV_DBG_TT, bat_priv,
896                                        "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
897                                        unicast_packet->dest, ethhdr->h_dest,
898                                        old_ttvn, curr_ttvn);
899                 return true;
900         }
901 
902         /* the packet has not been re-routed: either the destination is
903          * currently served by this node or there is no destination at all and
904          * it is possible to drop the packet
905          */
906         if (!batadv_is_my_client(bat_priv, ethhdr->h_dest, vid))
907                 return false;
908 
909         /* update the header in order to let the packet be delivered to this
910          * node's soft interface
911          */
912         primary_if = batadv_primary_if_get_selected(bat_priv);
913         if (!primary_if)
914                 return false;
915 
916         /* update the packet header */
917         skb_postpull_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
918         ether_addr_copy(unicast_packet->dest, primary_if->net_dev->dev_addr);
919         unicast_packet->ttvn = curr_ttvn;
920         skb_postpush_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
921 
922         batadv_hardif_put(primary_if);
923 
924         return true;
925 }
926 
927 /**
928  * batadv_recv_unhandled_unicast_packet() - receive and process packets which
929  *      are in the unicast number space but not yet known to the implementation
930  * @skb: unicast tvlv packet to process
931  * @recv_if: pointer to interface this packet was received on
932  *
933  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
934  * otherwise.
935  */
936 int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
937                                          struct batadv_hard_iface *recv_if)
938 {
939         struct batadv_unicast_packet *unicast_packet;
940         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
941         int check, hdr_size = sizeof(*unicast_packet);
942 
943         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
944         if (check < 0)
945                 goto free_skb;
946 
947         /* we don't know about this type, drop it. */
948         unicast_packet = (struct batadv_unicast_packet *)skb->data;
949         if (batadv_is_my_mac(bat_priv, unicast_packet->dest))
950                 goto free_skb;
951 
952         return batadv_route_unicast_packet(skb, recv_if);
953 
954 free_skb:
955         kfree_skb(skb);
956         return NET_RX_DROP;
957 }
958 
959 /**
960  * batadv_recv_unicast_packet() - Process incoming unicast packet
961  * @skb: incoming packet buffer
962  * @recv_if: incoming hard interface
963  *
964  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
965  */
966 int batadv_recv_unicast_packet(struct sk_buff *skb,
967                                struct batadv_hard_iface *recv_if)
968 {
969         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
970         struct batadv_unicast_packet *unicast_packet;
971         struct batadv_unicast_4addr_packet *unicast_4addr_packet;
972         u8 *orig_addr, *orig_addr_gw;
973         struct batadv_orig_node *orig_node = NULL, *orig_node_gw = NULL;
974         int check, hdr_size = sizeof(*unicast_packet);
975         enum batadv_subtype subtype;
976         int ret = NET_RX_DROP;
977         bool is4addr, is_gw;
978 
979         unicast_packet = (struct batadv_unicast_packet *)skb->data;
980         is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
981         /* the caller function should have already pulled 2 bytes */
982         if (is4addr)
983                 hdr_size = sizeof(*unicast_4addr_packet);
984 
985         /* function returns -EREMOTE for promiscuous packets */
986         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
987 
988         /* Even though the packet is not for us, we might save it to use for
989          * decoding a later received coded packet
990          */
991         if (check == -EREMOTE)
992                 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
993 
994         if (check < 0)
995                 goto free_skb;
996         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
997                 goto free_skb;
998 
999         unicast_packet = (struct batadv_unicast_packet *)skb->data;
1000 
1001         /* packet for me */
1002         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
1003                 /* If this is a unicast packet from another backgone gw,
1004                  * drop it.
1005                  */
1006                 orig_addr_gw = eth_hdr(skb)->h_source;
1007                 orig_node_gw = batadv_orig_hash_find(bat_priv, orig_addr_gw);
1008                 if (orig_node_gw) {
1009                         is_gw = batadv_bla_is_backbone_gw(skb, orig_node_gw,
1010                                                           hdr_size);
1011                         batadv_orig_node_put(orig_node_gw);
1012                         if (is_gw) {
1013                                 batadv_dbg(BATADV_DBG_BLA, bat_priv,
1014                                            "%s(): Dropped unicast pkt received from another backbone gw %pM.\n",
1015                                            __func__, orig_addr_gw);
1016                                 goto free_skb;
1017                         }
1018                 }
1019 
1020                 if (is4addr) {
1021                         unicast_4addr_packet =
1022                                 (struct batadv_unicast_4addr_packet *)skb->data;
1023                         subtype = unicast_4addr_packet->subtype;
1024                         batadv_dat_inc_counter(bat_priv, subtype);
1025 
1026                         /* Only payload data should be considered for speedy
1027                          * join. For example, DAT also uses unicast 4addr
1028                          * types, but those packets should not be considered
1029                          * for speedy join, since the clients do not actually
1030                          * reside at the sending originator.
1031                          */
1032                         if (subtype == BATADV_P_DATA) {
1033                                 orig_addr = unicast_4addr_packet->src;
1034                                 orig_node = batadv_orig_hash_find(bat_priv,
1035                                                                   orig_addr);
1036                         }
1037                 }
1038 
1039                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
1040                                                           hdr_size))
1041                         goto rx_success;
1042                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
1043                                                         hdr_size))
1044                         goto rx_success;
1045 
1046                 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size,
1047                                     orig_node);
1048 
1049 rx_success:
1050                 if (orig_node)
1051                         batadv_orig_node_put(orig_node);
1052 
1053                 return NET_RX_SUCCESS;
1054         }
1055 
1056         ret = batadv_route_unicast_packet(skb, recv_if);
1057         /* skb was consumed */
1058         skb = NULL;
1059 
1060 free_skb:
1061         kfree_skb(skb);
1062 
1063         return ret;
1064 }
1065 
1066 /**
1067  * batadv_recv_unicast_tvlv() - receive and process unicast tvlv packets
1068  * @skb: unicast tvlv packet to process
1069  * @recv_if: pointer to interface this packet was received on
1070  *
1071  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
1072  * otherwise.
1073  */
1074 int batadv_recv_unicast_tvlv(struct sk_buff *skb,
1075                              struct batadv_hard_iface *recv_if)
1076 {
1077         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1078         struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
1079         unsigned char *tvlv_buff;
1080         u16 tvlv_buff_len;
1081         int hdr_size = sizeof(*unicast_tvlv_packet);
1082         int ret = NET_RX_DROP;
1083 
1084         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
1085                 goto free_skb;
1086 
1087         /* the header is likely to be modified while forwarding */
1088         if (skb_cow(skb, hdr_size) < 0)
1089                 goto free_skb;
1090 
1091         /* packet needs to be linearized to access the tvlv content */
1092         if (skb_linearize(skb) < 0)
1093                 goto free_skb;
1094 
1095         unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)skb->data;
1096 
1097         tvlv_buff = (unsigned char *)(skb->data + hdr_size);
1098         tvlv_buff_len = ntohs(unicast_tvlv_packet->tvlv_len);
1099 
1100         if (tvlv_buff_len > skb->len - hdr_size)
1101                 goto free_skb;
1102 
1103         ret = batadv_tvlv_containers_process(bat_priv, false, NULL,
1104                                              unicast_tvlv_packet->src,
1105                                              unicast_tvlv_packet->dst,
1106                                              tvlv_buff, tvlv_buff_len);
1107 
1108         if (ret != NET_RX_SUCCESS) {
1109                 ret = batadv_route_unicast_packet(skb, recv_if);
1110                 /* skb was consumed */
1111                 skb = NULL;
1112         }
1113 
1114 free_skb:
1115         kfree_skb(skb);
1116 
1117         return ret;
1118 }
1119 
1120 /**
1121  * batadv_recv_frag_packet() - process received fragment
1122  * @skb: the received fragment
1123  * @recv_if: interface that the skb is received on
1124  *
1125  * This function does one of the three following things: 1) Forward fragment, if
1126  * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till
1127  * lack further fragments; 3) Merge fragments, if we have all needed parts.
1128  *
1129  * Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise.
1130  */
1131 int batadv_recv_frag_packet(struct sk_buff *skb,
1132                             struct batadv_hard_iface *recv_if)
1133 {
1134         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1135         struct batadv_orig_node *orig_node_src = NULL;
1136         struct batadv_frag_packet *frag_packet;
1137         int ret = NET_RX_DROP;
1138 
1139         if (batadv_check_unicast_packet(bat_priv, skb,
1140                                         sizeof(*frag_packet)) < 0)
1141                 goto free_skb;
1142 
1143         frag_packet = (struct batadv_frag_packet *)skb->data;
1144         orig_node_src = batadv_orig_hash_find(bat_priv, frag_packet->orig);
1145         if (!orig_node_src)
1146                 goto free_skb;
1147 
1148         skb->priority = frag_packet->priority + 256;
1149 
1150         /* Route the fragment if it is not for us and too big to be merged. */
1151         if (!batadv_is_my_mac(bat_priv, frag_packet->dest) &&
1152             batadv_frag_skb_fwd(skb, recv_if, orig_node_src)) {
1153                 /* skb was consumed */
1154                 skb = NULL;
1155                 ret = NET_RX_SUCCESS;
1156                 goto put_orig_node;
1157         }
1158 
1159         batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_RX);
1160         batadv_add_counter(bat_priv, BATADV_CNT_FRAG_RX_BYTES, skb->len);
1161 
1162         /* Add fragment to buffer and merge if possible. */
1163         if (!batadv_frag_skb_buffer(&skb, orig_node_src))
1164                 goto put_orig_node;
1165 
1166         /* Deliver merged packet to the appropriate handler, if it was
1167          * merged
1168          */
1169         if (skb) {
1170                 batadv_batman_skb_recv(skb, recv_if->net_dev,
1171                                        &recv_if->batman_adv_ptype, NULL);
1172                 /* skb was consumed */
1173                 skb = NULL;
1174         }
1175 
1176         ret = NET_RX_SUCCESS;
1177 
1178 put_orig_node:
1179         batadv_orig_node_put(orig_node_src);
1180 free_skb:
1181         kfree_skb(skb);
1182 
1183         return ret;
1184 }
1185 
1186 /**
1187  * batadv_recv_bcast_packet() - Process incoming broadcast packet
1188  * @skb: incoming packet buffer
1189  * @recv_if: incoming hard interface
1190  *
1191  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
1192  */
1193 int batadv_recv_bcast_packet(struct sk_buff *skb,
1194                              struct batadv_hard_iface *recv_if)
1195 {
1196         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1197         struct batadv_orig_node *orig_node = NULL;
1198         struct batadv_bcast_packet *bcast_packet;
1199         struct ethhdr *ethhdr;
1200         int hdr_size = sizeof(*bcast_packet);
1201         int ret = NET_RX_DROP;
1202         s32 seq_diff;
1203         u32 seqno;
1204 
1205         /* drop packet if it has not necessary minimum size */
1206         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1207                 goto free_skb;
1208 
1209         ethhdr = eth_hdr(skb);
1210 
1211         /* packet with broadcast indication but unicast recipient */
1212         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1213                 goto free_skb;
1214 
1215         /* packet with broadcast/multicast sender address */
1216         if (is_multicast_ether_addr(ethhdr->h_source))
1217                 goto free_skb;
1218 
1219         /* ignore broadcasts sent by myself */
1220         if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1221                 goto free_skb;
1222 
1223         bcast_packet = (struct batadv_bcast_packet *)skb->data;
1224 
1225         /* ignore broadcasts originated by myself */
1226         if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1227                 goto free_skb;
1228 
1229         if (bcast_packet->ttl < 2)
1230                 goto free_skb;
1231 
1232         orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1233 
1234         if (!orig_node)
1235                 goto free_skb;
1236 
1237         spin_lock_bh(&orig_node->bcast_seqno_lock);
1238 
1239         seqno = ntohl(bcast_packet->seqno);
1240         /* check whether the packet is a duplicate */
1241         if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1242                             seqno))
1243                 goto spin_unlock;
1244 
1245         seq_diff = seqno - orig_node->last_bcast_seqno;
1246 
1247         /* check whether the packet is old and the host just restarted. */
1248         if (batadv_window_protected(bat_priv, seq_diff,
1249                                     BATADV_BCAST_MAX_AGE,
1250                                     &orig_node->bcast_seqno_reset, NULL))
1251                 goto spin_unlock;
1252 
1253         /* mark broadcast in flood history, update window position
1254          * if required.
1255          */
1256         if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1257                 orig_node->last_bcast_seqno = seqno;
1258 
1259         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1260 
1261         /* check whether this has been sent by another originator before */
1262         if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1263                 goto free_skb;
1264 
1265         batadv_skb_set_priority(skb, sizeof(struct batadv_bcast_packet));
1266 
1267         /* rebroadcast packet */
1268         batadv_add_bcast_packet_to_list(bat_priv, skb, 1, false);
1269 
1270         /* don't hand the broadcast up if it is from an originator
1271          * from the same backbone.
1272          */
1273         if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1274                 goto free_skb;
1275 
1276         if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1277                 goto rx_success;
1278         if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1279                 goto rx_success;
1280 
1281         /* broadcast for me */
1282         batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node);
1283 
1284 rx_success:
1285         ret = NET_RX_SUCCESS;
1286         goto out;
1287 
1288 spin_unlock:
1289         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1290 free_skb:
1291         kfree_skb(skb);
1292 out:
1293         if (orig_node)
1294                 batadv_orig_node_put(orig_node);
1295         return ret;
1296 }
1297 

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