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1 | /* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors: | |
2 | * | |
3 | * Marek Lindner, Simon Wunderlich | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of version 2 of the GNU General Public | |
7 | * License as published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but | |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
12 | * General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA | |
17 | * 02110-1301, USA | |
18 | */ | |
19 | ||
20 | #include "main.h" | |
21 | #include "routing.h" | |
22 | #include "send.h" | |
23 | #include "soft-interface.h" | |
24 | #include "hard-interface.h" | |
25 | #include "icmp_socket.h" | |
26 | #include "translation-table.h" | |
27 | #include "originator.h" | |
28 | #include "vis.h" | |
29 | #include "unicast.h" | |
30 | #include "bridge_loop_avoidance.h" | |
31 | #include "distributed-arp-table.h" | |
32 | ||
33 | static int batadv_route_unicast_packet(struct sk_buff *skb, | |
34 | struct batadv_hard_iface *recv_if); | |
35 | ||
36 | void batadv_slide_own_bcast_window(struct batadv_hard_iface *hard_iface) | |
37 | { | |
38 | struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); | |
39 | struct batadv_hashtable *hash = bat_priv->orig_hash; | |
40 | struct hlist_head *head; | |
41 | struct batadv_orig_node *orig_node; | |
42 | unsigned long *word; | |
43 | uint32_t i; | |
44 | size_t word_index; | |
45 | uint8_t *w; | |
46 | ||
47 | for (i = 0; i < hash->size; i++) { | |
48 | head = &hash->table[i]; | |
49 | ||
50 | rcu_read_lock(); | |
51 | hlist_for_each_entry_rcu(orig_node, head, hash_entry) { | |
52 | spin_lock_bh(&orig_node->ogm_cnt_lock); | |
53 | word_index = hard_iface->if_num * BATADV_NUM_WORDS; | |
54 | word = &(orig_node->bcast_own[word_index]); | |
55 | ||
56 | batadv_bit_get_packet(bat_priv, word, 1, 0); | |
57 | w = &orig_node->bcast_own_sum[hard_iface->if_num]; | |
58 | *w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE); | |
59 | spin_unlock_bh(&orig_node->ogm_cnt_lock); | |
60 | } | |
61 | rcu_read_unlock(); | |
62 | } | |
63 | } | |
64 | ||
65 | static void _batadv_update_route(struct batadv_priv *bat_priv, | |
66 | struct batadv_orig_node *orig_node, | |
67 | struct batadv_neigh_node *neigh_node) | |
68 | { | |
69 | struct batadv_neigh_node *curr_router; | |
70 | ||
71 | curr_router = batadv_orig_node_get_router(orig_node); | |
72 | ||
73 | /* route deleted */ | |
74 | if ((curr_router) && (!neigh_node)) { | |
75 | batadv_dbg(BATADV_DBG_ROUTES, bat_priv, | |
76 | "Deleting route towards: %pM\n", orig_node->orig); | |
77 | batadv_tt_global_del_orig(bat_priv, orig_node, | |
78 | "Deleted route towards originator"); | |
79 | ||
80 | /* route added */ | |
81 | } else if ((!curr_router) && (neigh_node)) { | |
82 | batadv_dbg(BATADV_DBG_ROUTES, bat_priv, | |
83 | "Adding route towards: %pM (via %pM)\n", | |
84 | orig_node->orig, neigh_node->addr); | |
85 | /* route changed */ | |
86 | } else if (neigh_node && curr_router) { | |
87 | batadv_dbg(BATADV_DBG_ROUTES, bat_priv, | |
88 | "Changing route towards: %pM (now via %pM - was via %pM)\n", | |
89 | orig_node->orig, neigh_node->addr, | |
90 | curr_router->addr); | |
91 | } | |
92 | ||
93 | if (curr_router) | |
94 | batadv_neigh_node_free_ref(curr_router); | |
95 | ||
96 | /* increase refcount of new best neighbor */ | |
97 | if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount)) | |
98 | neigh_node = NULL; | |
99 | ||
100 | spin_lock_bh(&orig_node->neigh_list_lock); | |
101 | rcu_assign_pointer(orig_node->router, neigh_node); | |
102 | spin_unlock_bh(&orig_node->neigh_list_lock); | |
103 | ||
104 | /* decrease refcount of previous best neighbor */ | |
105 | if (curr_router) | |
106 | batadv_neigh_node_free_ref(curr_router); | |
107 | } | |
108 | ||
109 | void batadv_update_route(struct batadv_priv *bat_priv, | |
110 | struct batadv_orig_node *orig_node, | |
111 | struct batadv_neigh_node *neigh_node) | |
112 | { | |
113 | struct batadv_neigh_node *router = NULL; | |
114 | ||
115 | if (!orig_node) | |
116 | goto out; | |
117 | ||
118 | router = batadv_orig_node_get_router(orig_node); | |
119 | ||
120 | if (router != neigh_node) | |
121 | _batadv_update_route(bat_priv, orig_node, neigh_node); | |
122 | ||
123 | out: | |
124 | if (router) | |
125 | batadv_neigh_node_free_ref(router); | |
126 | } | |
127 | ||
128 | /* caller must hold the neigh_list_lock */ | |
129 | void batadv_bonding_candidate_del(struct batadv_orig_node *orig_node, | |
130 | struct batadv_neigh_node *neigh_node) | |
131 | { | |
132 | /* this neighbor is not part of our candidate list */ | |
133 | if (list_empty(&neigh_node->bonding_list)) | |
134 | goto out; | |
135 | ||
136 | list_del_rcu(&neigh_node->bonding_list); | |
137 | INIT_LIST_HEAD(&neigh_node->bonding_list); | |
138 | batadv_neigh_node_free_ref(neigh_node); | |
139 | atomic_dec(&orig_node->bond_candidates); | |
140 | ||
141 | out: | |
142 | return; | |
143 | } | |
144 | ||
145 | void batadv_bonding_candidate_add(struct batadv_orig_node *orig_node, | |
146 | struct batadv_neigh_node *neigh_node) | |
147 | { | |
148 | struct batadv_neigh_node *tmp_neigh_node, *router = NULL; | |
149 | uint8_t interference_candidate = 0; | |
150 | ||
151 | spin_lock_bh(&orig_node->neigh_list_lock); | |
152 | ||
153 | /* only consider if it has the same primary address ... */ | |
154 | if (!batadv_compare_eth(orig_node->orig, | |
155 | neigh_node->orig_node->primary_addr)) | |
156 | goto candidate_del; | |
157 | ||
158 | router = batadv_orig_node_get_router(orig_node); | |
159 | if (!router) | |
160 | goto candidate_del; | |
161 | ||
162 | /* ... and is good enough to be considered */ | |
163 | if (neigh_node->tq_avg < router->tq_avg - BATADV_BONDING_TQ_THRESHOLD) | |
164 | goto candidate_del; | |
165 | ||
166 | /* check if we have another candidate with the same mac address or | |
167 | * interface. If we do, we won't select this candidate because of | |
168 | * possible interference. | |
169 | */ | |
170 | hlist_for_each_entry_rcu(tmp_neigh_node, | |
171 | &orig_node->neigh_list, list) { | |
172 | if (tmp_neigh_node == neigh_node) | |
173 | continue; | |
174 | ||
175 | /* we only care if the other candidate is even | |
176 | * considered as candidate. | |
177 | */ | |
178 | if (list_empty(&tmp_neigh_node->bonding_list)) | |
179 | continue; | |
180 | ||
181 | if ((neigh_node->if_incoming == tmp_neigh_node->if_incoming) || | |
182 | (batadv_compare_eth(neigh_node->addr, | |
183 | tmp_neigh_node->addr))) { | |
184 | interference_candidate = 1; | |
185 | break; | |
186 | } | |
187 | } | |
188 | ||
189 | /* don't care further if it is an interference candidate */ | |
190 | if (interference_candidate) | |
191 | goto candidate_del; | |
192 | ||
193 | /* this neighbor already is part of our candidate list */ | |
194 | if (!list_empty(&neigh_node->bonding_list)) | |
195 | goto out; | |
196 | ||
197 | if (!atomic_inc_not_zero(&neigh_node->refcount)) | |
198 | goto out; | |
199 | ||
200 | list_add_rcu(&neigh_node->bonding_list, &orig_node->bond_list); | |
201 | atomic_inc(&orig_node->bond_candidates); | |
202 | goto out; | |
203 | ||
204 | candidate_del: | |
205 | batadv_bonding_candidate_del(orig_node, neigh_node); | |
206 | ||
207 | out: | |
208 | spin_unlock_bh(&orig_node->neigh_list_lock); | |
209 | ||
210 | if (router) | |
211 | batadv_neigh_node_free_ref(router); | |
212 | } | |
213 | ||
214 | /* copy primary address for bonding */ | |
215 | void | |
216 | batadv_bonding_save_primary(const struct batadv_orig_node *orig_node, | |
217 | struct batadv_orig_node *orig_neigh_node, | |
218 | const struct batadv_ogm_packet *batman_ogm_packet) | |
219 | { | |
220 | if (!(batman_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP)) | |
221 | return; | |
222 | ||
223 | memcpy(orig_neigh_node->primary_addr, orig_node->orig, ETH_ALEN); | |
224 | } | |
225 | ||
226 | /* checks whether the host restarted and is in the protection time. | |
227 | * returns: | |
228 | * 0 if the packet is to be accepted | |
229 | * 1 if the packet is to be ignored. | |
230 | */ | |
231 | int batadv_window_protected(struct batadv_priv *bat_priv, int32_t seq_num_diff, | |
232 | unsigned long *last_reset) | |
233 | { | |
234 | if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE || | |
235 | seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) { | |
236 | if (!batadv_has_timed_out(*last_reset, | |
237 | BATADV_RESET_PROTECTION_MS)) | |
238 | return 1; | |
239 | ||
240 | *last_reset = jiffies; | |
241 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
242 | "old packet received, start protection\n"); | |
243 | } | |
244 | ||
245 | return 0; | |
246 | } | |
247 | ||
248 | bool batadv_check_management_packet(struct sk_buff *skb, | |
249 | struct batadv_hard_iface *hard_iface, | |
250 | int header_len) | |
251 | { | |
252 | struct ethhdr *ethhdr; | |
253 | ||
254 | /* drop packet if it has not necessary minimum size */ | |
255 | if (unlikely(!pskb_may_pull(skb, header_len))) | |
256 | return false; | |
257 | ||
258 | ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
259 | ||
260 | /* packet with broadcast indication but unicast recipient */ | |
261 | if (!is_broadcast_ether_addr(ethhdr->h_dest)) | |
262 | return false; | |
263 | ||
264 | /* packet with broadcast sender address */ | |
265 | if (is_broadcast_ether_addr(ethhdr->h_source)) | |
266 | return false; | |
267 | ||
268 | /* create a copy of the skb, if needed, to modify it. */ | |
269 | if (skb_cow(skb, 0) < 0) | |
270 | return false; | |
271 | ||
272 | /* keep skb linear */ | |
273 | if (skb_linearize(skb) < 0) | |
274 | return false; | |
275 | ||
276 | return true; | |
277 | } | |
278 | ||
279 | static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, | |
280 | struct sk_buff *skb, size_t icmp_len) | |
281 | { | |
282 | struct batadv_hard_iface *primary_if = NULL; | |
283 | struct batadv_orig_node *orig_node = NULL; | |
284 | struct batadv_icmp_packet_rr *icmp_packet; | |
285 | int ret = NET_RX_DROP; | |
286 | ||
287 | icmp_packet = (struct batadv_icmp_packet_rr *)skb->data; | |
288 | ||
289 | /* add data to device queue */ | |
290 | if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) { | |
291 | batadv_socket_receive_packet(icmp_packet, icmp_len); | |
292 | goto out; | |
293 | } | |
294 | ||
295 | primary_if = batadv_primary_if_get_selected(bat_priv); | |
296 | if (!primary_if) | |
297 | goto out; | |
298 | ||
299 | /* answer echo request (ping) */ | |
300 | /* get routing information */ | |
301 | orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig); | |
302 | if (!orig_node) | |
303 | goto out; | |
304 | ||
305 | /* create a copy of the skb, if needed, to modify it. */ | |
306 | if (skb_cow(skb, ETH_HLEN) < 0) | |
307 | goto out; | |
308 | ||
309 | icmp_packet = (struct batadv_icmp_packet_rr *)skb->data; | |
310 | ||
311 | memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN); | |
312 | memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN); | |
313 | icmp_packet->msg_type = BATADV_ECHO_REPLY; | |
314 | icmp_packet->header.ttl = BATADV_TTL; | |
315 | ||
316 | if (batadv_send_skb_to_orig(skb, orig_node, NULL)) | |
317 | ret = NET_RX_SUCCESS; | |
318 | ||
319 | out: | |
320 | if (primary_if) | |
321 | batadv_hardif_free_ref(primary_if); | |
322 | if (orig_node) | |
323 | batadv_orig_node_free_ref(orig_node); | |
324 | return ret; | |
325 | } | |
326 | ||
327 | static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv, | |
328 | struct sk_buff *skb) | |
329 | { | |
330 | struct batadv_hard_iface *primary_if = NULL; | |
331 | struct batadv_orig_node *orig_node = NULL; | |
332 | struct batadv_icmp_packet *icmp_packet; | |
333 | int ret = NET_RX_DROP; | |
334 | ||
335 | icmp_packet = (struct batadv_icmp_packet *)skb->data; | |
336 | ||
337 | /* send TTL exceeded if packet is an echo request (traceroute) */ | |
338 | if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) { | |
339 | pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n", | |
340 | icmp_packet->orig, icmp_packet->dst); | |
341 | goto out; | |
342 | } | |
343 | ||
344 | primary_if = batadv_primary_if_get_selected(bat_priv); | |
345 | if (!primary_if) | |
346 | goto out; | |
347 | ||
348 | /* get routing information */ | |
349 | orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig); | |
350 | if (!orig_node) | |
351 | goto out; | |
352 | ||
353 | /* create a copy of the skb, if needed, to modify it. */ | |
354 | if (skb_cow(skb, ETH_HLEN) < 0) | |
355 | goto out; | |
356 | ||
357 | icmp_packet = (struct batadv_icmp_packet *)skb->data; | |
358 | ||
359 | memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN); | |
360 | memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN); | |
361 | icmp_packet->msg_type = BATADV_TTL_EXCEEDED; | |
362 | icmp_packet->header.ttl = BATADV_TTL; | |
363 | ||
364 | if (batadv_send_skb_to_orig(skb, orig_node, NULL)) | |
365 | ret = NET_RX_SUCCESS; | |
366 | ||
367 | out: | |
368 | if (primary_if) | |
369 | batadv_hardif_free_ref(primary_if); | |
370 | if (orig_node) | |
371 | batadv_orig_node_free_ref(orig_node); | |
372 | return ret; | |
373 | } | |
374 | ||
375 | ||
376 | int batadv_recv_icmp_packet(struct sk_buff *skb, | |
377 | struct batadv_hard_iface *recv_if) | |
378 | { | |
379 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
380 | struct batadv_icmp_packet_rr *icmp_packet; | |
381 | struct ethhdr *ethhdr; | |
382 | struct batadv_orig_node *orig_node = NULL; | |
383 | int hdr_size = sizeof(struct batadv_icmp_packet); | |
384 | int ret = NET_RX_DROP; | |
385 | ||
386 | /* we truncate all incoming icmp packets if they don't match our size */ | |
387 | if (skb->len >= sizeof(struct batadv_icmp_packet_rr)) | |
388 | hdr_size = sizeof(struct batadv_icmp_packet_rr); | |
389 | ||
390 | /* drop packet if it has not necessary minimum size */ | |
391 | if (unlikely(!pskb_may_pull(skb, hdr_size))) | |
392 | goto out; | |
393 | ||
394 | ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
395 | ||
396 | /* packet with unicast indication but broadcast recipient */ | |
397 | if (is_broadcast_ether_addr(ethhdr->h_dest)) | |
398 | goto out; | |
399 | ||
400 | /* packet with broadcast sender address */ | |
401 | if (is_broadcast_ether_addr(ethhdr->h_source)) | |
402 | goto out; | |
403 | ||
404 | /* not for me */ | |
405 | if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest)) | |
406 | goto out; | |
407 | ||
408 | icmp_packet = (struct batadv_icmp_packet_rr *)skb->data; | |
409 | ||
410 | /* add record route information if not full */ | |
411 | if ((hdr_size == sizeof(struct batadv_icmp_packet_rr)) && | |
412 | (icmp_packet->rr_cur < BATADV_RR_LEN)) { | |
413 | memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]), | |
414 | ethhdr->h_dest, ETH_ALEN); | |
415 | icmp_packet->rr_cur++; | |
416 | } | |
417 | ||
418 | /* packet for me */ | |
419 | if (batadv_is_my_mac(bat_priv, icmp_packet->dst)) | |
420 | return batadv_recv_my_icmp_packet(bat_priv, skb, hdr_size); | |
421 | ||
422 | /* TTL exceeded */ | |
423 | if (icmp_packet->header.ttl < 2) | |
424 | return batadv_recv_icmp_ttl_exceeded(bat_priv, skb); | |
425 | ||
426 | /* get routing information */ | |
427 | orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->dst); | |
428 | if (!orig_node) | |
429 | goto out; | |
430 | ||
431 | /* create a copy of the skb, if needed, to modify it. */ | |
432 | if (skb_cow(skb, ETH_HLEN) < 0) | |
433 | goto out; | |
434 | ||
435 | icmp_packet = (struct batadv_icmp_packet_rr *)skb->data; | |
436 | ||
437 | /* decrement ttl */ | |
438 | icmp_packet->header.ttl--; | |
439 | ||
440 | /* route it */ | |
441 | if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) | |
442 | ret = NET_RX_SUCCESS; | |
443 | ||
444 | out: | |
445 | if (orig_node) | |
446 | batadv_orig_node_free_ref(orig_node); | |
447 | return ret; | |
448 | } | |
449 | ||
450 | /* In the bonding case, send the packets in a round | |
451 | * robin fashion over the remaining interfaces. | |
452 | * | |
453 | * This method rotates the bonding list and increases the | |
454 | * returned router's refcount. | |
455 | */ | |
456 | static struct batadv_neigh_node * | |
457 | batadv_find_bond_router(struct batadv_orig_node *primary_orig, | |
458 | const struct batadv_hard_iface *recv_if) | |
459 | { | |
460 | struct batadv_neigh_node *tmp_neigh_node; | |
461 | struct batadv_neigh_node *router = NULL, *first_candidate = NULL; | |
462 | ||
463 | rcu_read_lock(); | |
464 | list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list, | |
465 | bonding_list) { | |
466 | if (!first_candidate) | |
467 | first_candidate = tmp_neigh_node; | |
468 | ||
469 | /* recv_if == NULL on the first node. */ | |
470 | if (tmp_neigh_node->if_incoming == recv_if) | |
471 | continue; | |
472 | ||
473 | if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) | |
474 | continue; | |
475 | ||
476 | router = tmp_neigh_node; | |
477 | break; | |
478 | } | |
479 | ||
480 | /* use the first candidate if nothing was found. */ | |
481 | if (!router && first_candidate && | |
482 | atomic_inc_not_zero(&first_candidate->refcount)) | |
483 | router = first_candidate; | |
484 | ||
485 | if (!router) | |
486 | goto out; | |
487 | ||
488 | /* selected should point to the next element | |
489 | * after the current router | |
490 | */ | |
491 | spin_lock_bh(&primary_orig->neigh_list_lock); | |
492 | /* this is a list_move(), which unfortunately | |
493 | * does not exist as rcu version | |
494 | */ | |
495 | list_del_rcu(&primary_orig->bond_list); | |
496 | list_add_rcu(&primary_orig->bond_list, | |
497 | &router->bonding_list); | |
498 | spin_unlock_bh(&primary_orig->neigh_list_lock); | |
499 | ||
500 | out: | |
501 | rcu_read_unlock(); | |
502 | return router; | |
503 | } | |
504 | ||
505 | /* Interface Alternating: Use the best of the | |
506 | * remaining candidates which are not using | |
507 | * this interface. | |
508 | * | |
509 | * Increases the returned router's refcount | |
510 | */ | |
511 | static struct batadv_neigh_node * | |
512 | batadv_find_ifalter_router(struct batadv_orig_node *primary_orig, | |
513 | const struct batadv_hard_iface *recv_if) | |
514 | { | |
515 | struct batadv_neigh_node *tmp_neigh_node; | |
516 | struct batadv_neigh_node *router = NULL, *first_candidate = NULL; | |
517 | ||
518 | rcu_read_lock(); | |
519 | list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list, | |
520 | bonding_list) { | |
521 | if (!first_candidate) | |
522 | first_candidate = tmp_neigh_node; | |
523 | ||
524 | /* recv_if == NULL on the first node. */ | |
525 | if (tmp_neigh_node->if_incoming == recv_if) | |
526 | continue; | |
527 | ||
528 | if (router && tmp_neigh_node->tq_avg <= router->tq_avg) | |
529 | continue; | |
530 | ||
531 | if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) | |
532 | continue; | |
533 | ||
534 | /* decrement refcount of previously selected router */ | |
535 | if (router) | |
536 | batadv_neigh_node_free_ref(router); | |
537 | ||
538 | /* we found a better router (or at least one valid router) */ | |
539 | router = tmp_neigh_node; | |
540 | } | |
541 | ||
542 | /* use the first candidate if nothing was found. */ | |
543 | if (!router && first_candidate && | |
544 | atomic_inc_not_zero(&first_candidate->refcount)) | |
545 | router = first_candidate; | |
546 | ||
547 | rcu_read_unlock(); | |
548 | return router; | |
549 | } | |
550 | ||
551 | static int batadv_check_unicast_packet(struct batadv_priv *bat_priv, | |
552 | struct sk_buff *skb, int hdr_size) | |
553 | { | |
554 | struct ethhdr *ethhdr; | |
555 | ||
556 | /* drop packet if it has not necessary minimum size */ | |
557 | if (unlikely(!pskb_may_pull(skb, hdr_size))) | |
558 | return -1; | |
559 | ||
560 | ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
561 | ||
562 | /* packet with unicast indication but broadcast recipient */ | |
563 | if (is_broadcast_ether_addr(ethhdr->h_dest)) | |
564 | return -1; | |
565 | ||
566 | /* packet with broadcast sender address */ | |
567 | if (is_broadcast_ether_addr(ethhdr->h_source)) | |
568 | return -1; | |
569 | ||
570 | /* not for me */ | |
571 | if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest)) | |
572 | return -1; | |
573 | ||
574 | return 0; | |
575 | } | |
576 | ||
577 | int batadv_recv_tt_query(struct sk_buff *skb, struct batadv_hard_iface *recv_if) | |
578 | { | |
579 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
580 | struct batadv_tt_query_packet *tt_query; | |
581 | uint16_t tt_size; | |
582 | int hdr_size = sizeof(*tt_query); | |
583 | char tt_flag; | |
584 | size_t packet_size; | |
585 | ||
586 | if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0) | |
587 | return NET_RX_DROP; | |
588 | ||
589 | /* I could need to modify it */ | |
590 | if (skb_cow(skb, sizeof(struct batadv_tt_query_packet)) < 0) | |
591 | goto out; | |
592 | ||
593 | tt_query = (struct batadv_tt_query_packet *)skb->data; | |
594 | ||
595 | switch (tt_query->flags & BATADV_TT_QUERY_TYPE_MASK) { | |
596 | case BATADV_TT_REQUEST: | |
597 | batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX); | |
598 | ||
599 | /* If we cannot provide an answer the tt_request is | |
600 | * forwarded | |
601 | */ | |
602 | if (!batadv_send_tt_response(bat_priv, tt_query)) { | |
603 | if (tt_query->flags & BATADV_TT_FULL_TABLE) | |
604 | tt_flag = 'F'; | |
605 | else | |
606 | tt_flag = '.'; | |
607 | ||
608 | batadv_dbg(BATADV_DBG_TT, bat_priv, | |
609 | "Routing TT_REQUEST to %pM [%c]\n", | |
610 | tt_query->dst, | |
611 | tt_flag); | |
612 | return batadv_route_unicast_packet(skb, recv_if); | |
613 | } | |
614 | break; | |
615 | case BATADV_TT_RESPONSE: | |
616 | batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX); | |
617 | ||
618 | if (batadv_is_my_mac(bat_priv, tt_query->dst)) { | |
619 | /* packet needs to be linearized to access the TT | |
620 | * changes | |
621 | */ | |
622 | if (skb_linearize(skb) < 0) | |
623 | goto out; | |
624 | /* skb_linearize() possibly changed skb->data */ | |
625 | tt_query = (struct batadv_tt_query_packet *)skb->data; | |
626 | ||
627 | tt_size = batadv_tt_len(ntohs(tt_query->tt_data)); | |
628 | ||
629 | /* Ensure we have all the claimed data */ | |
630 | packet_size = sizeof(struct batadv_tt_query_packet); | |
631 | packet_size += tt_size; | |
632 | if (unlikely(skb_headlen(skb) < packet_size)) | |
633 | goto out; | |
634 | ||
635 | batadv_handle_tt_response(bat_priv, tt_query); | |
636 | } else { | |
637 | if (tt_query->flags & BATADV_TT_FULL_TABLE) | |
638 | tt_flag = 'F'; | |
639 | else | |
640 | tt_flag = '.'; | |
641 | batadv_dbg(BATADV_DBG_TT, bat_priv, | |
642 | "Routing TT_RESPONSE to %pM [%c]\n", | |
643 | tt_query->dst, | |
644 | tt_flag); | |
645 | return batadv_route_unicast_packet(skb, recv_if); | |
646 | } | |
647 | break; | |
648 | } | |
649 | ||
650 | out: | |
651 | /* returning NET_RX_DROP will make the caller function kfree the skb */ | |
652 | return NET_RX_DROP; | |
653 | } | |
654 | ||
655 | int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if) | |
656 | { | |
657 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
658 | struct batadv_roam_adv_packet *roam_adv_packet; | |
659 | struct batadv_orig_node *orig_node; | |
660 | ||
661 | if (batadv_check_unicast_packet(bat_priv, skb, | |
662 | sizeof(*roam_adv_packet)) < 0) | |
663 | goto out; | |
664 | ||
665 | batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX); | |
666 | ||
667 | roam_adv_packet = (struct batadv_roam_adv_packet *)skb->data; | |
668 | ||
669 | if (!batadv_is_my_mac(bat_priv, roam_adv_packet->dst)) | |
670 | return batadv_route_unicast_packet(skb, recv_if); | |
671 | ||
672 | /* check if it is a backbone gateway. we don't accept | |
673 | * roaming advertisement from it, as it has the same | |
674 | * entries as we have. | |
675 | */ | |
676 | if (batadv_bla_is_backbone_gw_orig(bat_priv, roam_adv_packet->src)) | |
677 | goto out; | |
678 | ||
679 | orig_node = batadv_orig_hash_find(bat_priv, roam_adv_packet->src); | |
680 | if (!orig_node) | |
681 | goto out; | |
682 | ||
683 | batadv_dbg(BATADV_DBG_TT, bat_priv, | |
684 | "Received ROAMING_ADV from %pM (client %pM)\n", | |
685 | roam_adv_packet->src, roam_adv_packet->client); | |
686 | ||
687 | batadv_tt_global_add(bat_priv, orig_node, roam_adv_packet->client, | |
688 | BATADV_TT_CLIENT_ROAM, | |
689 | atomic_read(&orig_node->last_ttvn) + 1); | |
690 | ||
691 | batadv_orig_node_free_ref(orig_node); | |
692 | out: | |
693 | /* returning NET_RX_DROP will make the caller function kfree the skb */ | |
694 | return NET_RX_DROP; | |
695 | } | |
696 | ||
697 | /* find a suitable router for this originator, and use | |
698 | * bonding if possible. increases the found neighbors | |
699 | * refcount. | |
700 | */ | |
701 | struct batadv_neigh_node * | |
702 | batadv_find_router(struct batadv_priv *bat_priv, | |
703 | struct batadv_orig_node *orig_node, | |
704 | const struct batadv_hard_iface *recv_if) | |
705 | { | |
706 | struct batadv_orig_node *primary_orig_node; | |
707 | struct batadv_orig_node *router_orig; | |
708 | struct batadv_neigh_node *router; | |
709 | static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0}; | |
710 | int bonding_enabled; | |
711 | uint8_t *primary_addr; | |
712 | ||
713 | if (!orig_node) | |
714 | return NULL; | |
715 | ||
716 | router = batadv_orig_node_get_router(orig_node); | |
717 | if (!router) | |
718 | goto err; | |
719 | ||
720 | /* without bonding, the first node should | |
721 | * always choose the default router. | |
722 | */ | |
723 | bonding_enabled = atomic_read(&bat_priv->bonding); | |
724 | ||
725 | rcu_read_lock(); | |
726 | /* select default router to output */ | |
727 | router_orig = router->orig_node; | |
728 | if (!router_orig) | |
729 | goto err_unlock; | |
730 | ||
731 | if ((!recv_if) && (!bonding_enabled)) | |
732 | goto return_router; | |
733 | ||
734 | primary_addr = router_orig->primary_addr; | |
735 | ||
736 | /* if we have something in the primary_addr, we can search | |
737 | * for a potential bonding candidate. | |
738 | */ | |
739 | if (batadv_compare_eth(primary_addr, zero_mac)) | |
740 | goto return_router; | |
741 | ||
742 | /* find the orig_node which has the primary interface. might | |
743 | * even be the same as our router_orig in many cases | |
744 | */ | |
745 | if (batadv_compare_eth(primary_addr, router_orig->orig)) { | |
746 | primary_orig_node = router_orig; | |
747 | } else { | |
748 | primary_orig_node = batadv_orig_hash_find(bat_priv, | |
749 | primary_addr); | |
750 | if (!primary_orig_node) | |
751 | goto return_router; | |
752 | ||
753 | batadv_orig_node_free_ref(primary_orig_node); | |
754 | } | |
755 | ||
756 | /* with less than 2 candidates, we can't do any | |
757 | * bonding and prefer the original router. | |
758 | */ | |
759 | if (atomic_read(&primary_orig_node->bond_candidates) < 2) | |
760 | goto return_router; | |
761 | ||
762 | /* all nodes between should choose a candidate which | |
763 | * is is not on the interface where the packet came | |
764 | * in. | |
765 | */ | |
766 | batadv_neigh_node_free_ref(router); | |
767 | ||
768 | if (bonding_enabled) | |
769 | router = batadv_find_bond_router(primary_orig_node, recv_if); | |
770 | else | |
771 | router = batadv_find_ifalter_router(primary_orig_node, recv_if); | |
772 | ||
773 | return_router: | |
774 | if (router && router->if_incoming->if_status != BATADV_IF_ACTIVE) | |
775 | goto err_unlock; | |
776 | ||
777 | rcu_read_unlock(); | |
778 | return router; | |
779 | err_unlock: | |
780 | rcu_read_unlock(); | |
781 | err: | |
782 | if (router) | |
783 | batadv_neigh_node_free_ref(router); | |
784 | return NULL; | |
785 | } | |
786 | ||
787 | static int batadv_route_unicast_packet(struct sk_buff *skb, | |
788 | struct batadv_hard_iface *recv_if) | |
789 | { | |
790 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
791 | struct batadv_orig_node *orig_node = NULL; | |
792 | struct batadv_neigh_node *neigh_node = NULL; | |
793 | struct batadv_unicast_packet *unicast_packet; | |
794 | struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
795 | int ret = NET_RX_DROP; | |
796 | struct sk_buff *new_skb; | |
797 | ||
798 | unicast_packet = (struct batadv_unicast_packet *)skb->data; | |
799 | ||
800 | /* TTL exceeded */ | |
801 | if (unicast_packet->header.ttl < 2) { | |
802 | pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n", | |
803 | ethhdr->h_source, unicast_packet->dest); | |
804 | goto out; | |
805 | } | |
806 | ||
807 | /* get routing information */ | |
808 | orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest); | |
809 | ||
810 | if (!orig_node) | |
811 | goto out; | |
812 | ||
813 | /* find_router() increases neigh_nodes refcount if found. */ | |
814 | neigh_node = batadv_find_router(bat_priv, orig_node, recv_if); | |
815 | ||
816 | if (!neigh_node) | |
817 | goto out; | |
818 | ||
819 | /* create a copy of the skb, if needed, to modify it. */ | |
820 | if (skb_cow(skb, ETH_HLEN) < 0) | |
821 | goto out; | |
822 | ||
823 | unicast_packet = (struct batadv_unicast_packet *)skb->data; | |
824 | ||
825 | if (unicast_packet->header.packet_type == BATADV_UNICAST && | |
826 | atomic_read(&bat_priv->fragmentation) && | |
827 | skb->len > neigh_node->if_incoming->net_dev->mtu) { | |
828 | ret = batadv_frag_send_skb(skb, bat_priv, | |
829 | neigh_node->if_incoming, | |
830 | neigh_node->addr); | |
831 | goto out; | |
832 | } | |
833 | ||
834 | if (unicast_packet->header.packet_type == BATADV_UNICAST_FRAG && | |
835 | batadv_frag_can_reassemble(skb, | |
836 | neigh_node->if_incoming->net_dev->mtu)) { | |
837 | ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb); | |
838 | ||
839 | if (ret == NET_RX_DROP) | |
840 | goto out; | |
841 | ||
842 | /* packet was buffered for late merge */ | |
843 | if (!new_skb) { | |
844 | ret = NET_RX_SUCCESS; | |
845 | goto out; | |
846 | } | |
847 | ||
848 | skb = new_skb; | |
849 | unicast_packet = (struct batadv_unicast_packet *)skb->data; | |
850 | } | |
851 | ||
852 | /* decrement ttl */ | |
853 | unicast_packet->header.ttl--; | |
854 | ||
855 | /* Update stats counter */ | |
856 | batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD); | |
857 | batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES, | |
858 | skb->len + ETH_HLEN); | |
859 | ||
860 | /* route it */ | |
861 | if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) | |
862 | ret = NET_RX_SUCCESS; | |
863 | ||
864 | out: | |
865 | if (neigh_node) | |
866 | batadv_neigh_node_free_ref(neigh_node); | |
867 | if (orig_node) | |
868 | batadv_orig_node_free_ref(orig_node); | |
869 | return ret; | |
870 | } | |
871 | ||
872 | /** | |
873 | * batadv_reroute_unicast_packet - update the unicast header for re-routing | |
874 | * @bat_priv: the bat priv with all the soft interface information | |
875 | * @unicast_packet: the unicast header to be updated | |
876 | * @dst_addr: the payload destination | |
877 | * | |
878 | * Search the translation table for dst_addr and update the unicast header with | |
879 | * the new corresponding information (originator address where the destination | |
880 | * client currently is and its known TTVN) | |
881 | * | |
882 | * Returns true if the packet header has been updated, false otherwise | |
883 | */ | |
884 | static bool | |
885 | batadv_reroute_unicast_packet(struct batadv_priv *bat_priv, | |
886 | struct batadv_unicast_packet *unicast_packet, | |
887 | uint8_t *dst_addr) | |
888 | { | |
889 | struct batadv_orig_node *orig_node = NULL; | |
890 | struct batadv_hard_iface *primary_if = NULL; | |
891 | bool ret = false; | |
892 | uint8_t *orig_addr, orig_ttvn; | |
893 | ||
894 | if (batadv_is_my_client(bat_priv, dst_addr)) { | |
895 | primary_if = batadv_primary_if_get_selected(bat_priv); | |
896 | if (!primary_if) | |
897 | goto out; | |
898 | orig_addr = primary_if->net_dev->dev_addr; | |
899 | orig_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn); | |
900 | } else { | |
901 | orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr); | |
902 | if (!orig_node) | |
903 | goto out; | |
904 | ||
905 | if (batadv_compare_eth(orig_node->orig, unicast_packet->dest)) | |
906 | goto out; | |
907 | ||
908 | orig_addr = orig_node->orig; | |
909 | orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn); | |
910 | } | |
911 | ||
912 | /* update the packet header */ | |
913 | memcpy(unicast_packet->dest, orig_addr, ETH_ALEN); | |
914 | unicast_packet->ttvn = orig_ttvn; | |
915 | ||
916 | ret = true; | |
917 | out: | |
918 | if (primary_if) | |
919 | batadv_hardif_free_ref(primary_if); | |
920 | if (orig_node) | |
921 | batadv_orig_node_free_ref(orig_node); | |
922 | ||
923 | return ret; | |
924 | } | |
925 | ||
926 | static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, | |
927 | struct sk_buff *skb) { | |
928 | uint8_t curr_ttvn, old_ttvn; | |
929 | struct batadv_orig_node *orig_node; | |
930 | struct ethhdr *ethhdr; | |
931 | struct batadv_hard_iface *primary_if; | |
932 | struct batadv_unicast_packet *unicast_packet; | |
933 | int is_old_ttvn; | |
934 | ||
935 | /* check if there is enough data before accessing it */ | |
936 | if (pskb_may_pull(skb, sizeof(*unicast_packet) + ETH_HLEN) < 0) | |
937 | return 0; | |
938 | ||
939 | /* create a copy of the skb (in case of for re-routing) to modify it. */ | |
940 | if (skb_cow(skb, sizeof(*unicast_packet)) < 0) | |
941 | return 0; | |
942 | ||
943 | unicast_packet = (struct batadv_unicast_packet *)skb->data; | |
944 | ethhdr = (struct ethhdr *)(skb->data + sizeof(*unicast_packet)); | |
945 | ||
946 | /* check if the destination client was served by this node and it is now | |
947 | * roaming. In this case, it means that the node has got a ROAM_ADV | |
948 | * message and that it knows the new destination in the mesh to re-route | |
949 | * the packet to | |
950 | */ | |
951 | if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest)) { | |
952 | if (batadv_reroute_unicast_packet(bat_priv, unicast_packet, | |
953 | ethhdr->h_dest)) | |
954 | net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, | |
955 | bat_priv, | |
956 | "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n", | |
957 | unicast_packet->dest, | |
958 | ethhdr->h_dest); | |
959 | /* at this point the mesh destination should have been | |
960 | * substituted with the originator address found in the global | |
961 | * table. If not, let the packet go untouched anyway because | |
962 | * there is nothing the node can do | |
963 | */ | |
964 | return 1; | |
965 | } | |
966 | ||
967 | /* retrieve the TTVN known by this node for the packet destination. This | |
968 | * value is used later to check if the node which sent (or re-routed | |
969 | * last time) the packet had an updated information or not | |
970 | */ | |
971 | curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn); | |
972 | if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) { | |
973 | orig_node = batadv_orig_hash_find(bat_priv, | |
974 | unicast_packet->dest); | |
975 | /* if it is not possible to find the orig_node representing the | |
976 | * destination, the packet can immediately be dropped as it will | |
977 | * not be possible to deliver it | |
978 | */ | |
979 | if (!orig_node) | |
980 | return 0; | |
981 | ||
982 | curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn); | |
983 | batadv_orig_node_free_ref(orig_node); | |
984 | } | |
985 | ||
986 | /* check if the TTVN contained in the packet is fresher than what the | |
987 | * node knows | |
988 | */ | |
989 | is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn); | |
990 | if (!is_old_ttvn) | |
991 | return 1; | |
992 | ||
993 | old_ttvn = unicast_packet->ttvn; | |
994 | /* the packet was forged based on outdated network information. Its | |
995 | * destination can possibly be updated and forwarded towards the new | |
996 | * target host | |
997 | */ | |
998 | if (batadv_reroute_unicast_packet(bat_priv, unicast_packet, | |
999 | ethhdr->h_dest)) { | |
1000 | net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, bat_priv, | |
1001 | "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n", | |
1002 | unicast_packet->dest, ethhdr->h_dest, | |
1003 | old_ttvn, curr_ttvn); | |
1004 | return 1; | |
1005 | } | |
1006 | ||
1007 | /* the packet has not been re-routed: either the destination is | |
1008 | * currently served by this node or there is no destination at all and | |
1009 | * it is possible to drop the packet | |
1010 | */ | |
1011 | if (!batadv_is_my_client(bat_priv, ethhdr->h_dest)) | |
1012 | return 0; | |
1013 | ||
1014 | /* update the header in order to let the packet be delivered to this | |
1015 | * node's soft interface | |
1016 | */ | |
1017 | primary_if = batadv_primary_if_get_selected(bat_priv); | |
1018 | if (!primary_if) | |
1019 | return 0; | |
1020 | ||
1021 | memcpy(unicast_packet->dest, primary_if->net_dev->dev_addr, ETH_ALEN); | |
1022 | ||
1023 | batadv_hardif_free_ref(primary_if); | |
1024 | ||
1025 | unicast_packet->ttvn = curr_ttvn; | |
1026 | ||
1027 | return 1; | |
1028 | } | |
1029 | ||
1030 | int batadv_recv_unicast_packet(struct sk_buff *skb, | |
1031 | struct batadv_hard_iface *recv_if) | |
1032 | { | |
1033 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
1034 | struct batadv_unicast_packet *unicast_packet; | |
1035 | struct batadv_unicast_4addr_packet *unicast_4addr_packet; | |
1036 | uint8_t *orig_addr; | |
1037 | struct batadv_orig_node *orig_node = NULL; | |
1038 | int hdr_size = sizeof(*unicast_packet); | |
1039 | bool is4addr; | |
1040 | ||
1041 | unicast_packet = (struct batadv_unicast_packet *)skb->data; | |
1042 | unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; | |
1043 | ||
1044 | is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR; | |
1045 | /* the caller function should have already pulled 2 bytes */ | |
1046 | if (is4addr) | |
1047 | hdr_size = sizeof(*unicast_4addr_packet); | |
1048 | ||
1049 | if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0) | |
1050 | return NET_RX_DROP; | |
1051 | ||
1052 | if (!batadv_check_unicast_ttvn(bat_priv, skb)) | |
1053 | return NET_RX_DROP; | |
1054 | ||
1055 | /* packet for me */ | |
1056 | if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) { | |
1057 | if (is4addr) { | |
1058 | batadv_dat_inc_counter(bat_priv, | |
1059 | unicast_4addr_packet->subtype); | |
1060 | orig_addr = unicast_4addr_packet->src; | |
1061 | orig_node = batadv_orig_hash_find(bat_priv, orig_addr); | |
1062 | } | |
1063 | ||
1064 | if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, | |
1065 | hdr_size)) | |
1066 | goto rx_success; | |
1067 | if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, | |
1068 | hdr_size)) | |
1069 | goto rx_success; | |
1070 | ||
1071 | batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, | |
1072 | orig_node); | |
1073 | ||
1074 | rx_success: | |
1075 | if (orig_node) | |
1076 | batadv_orig_node_free_ref(orig_node); | |
1077 | ||
1078 | return NET_RX_SUCCESS; | |
1079 | } | |
1080 | ||
1081 | return batadv_route_unicast_packet(skb, recv_if); | |
1082 | } | |
1083 | ||
1084 | int batadv_recv_ucast_frag_packet(struct sk_buff *skb, | |
1085 | struct batadv_hard_iface *recv_if) | |
1086 | { | |
1087 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
1088 | struct batadv_unicast_frag_packet *unicast_packet; | |
1089 | int hdr_size = sizeof(*unicast_packet); | |
1090 | struct sk_buff *new_skb = NULL; | |
1091 | int ret; | |
1092 | ||
1093 | if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0) | |
1094 | return NET_RX_DROP; | |
1095 | ||
1096 | if (!batadv_check_unicast_ttvn(bat_priv, skb)) | |
1097 | return NET_RX_DROP; | |
1098 | ||
1099 | unicast_packet = (struct batadv_unicast_frag_packet *)skb->data; | |
1100 | ||
1101 | /* packet for me */ | |
1102 | if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) { | |
1103 | ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb); | |
1104 | ||
1105 | if (ret == NET_RX_DROP) | |
1106 | return NET_RX_DROP; | |
1107 | ||
1108 | /* packet was buffered for late merge */ | |
1109 | if (!new_skb) | |
1110 | return NET_RX_SUCCESS; | |
1111 | ||
1112 | if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb, | |
1113 | hdr_size)) | |
1114 | goto rx_success; | |
1115 | if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb, | |
1116 | hdr_size)) | |
1117 | goto rx_success; | |
1118 | ||
1119 | batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if, | |
1120 | sizeof(struct batadv_unicast_packet), NULL); | |
1121 | ||
1122 | rx_success: | |
1123 | return NET_RX_SUCCESS; | |
1124 | } | |
1125 | ||
1126 | return batadv_route_unicast_packet(skb, recv_if); | |
1127 | } | |
1128 | ||
1129 | ||
1130 | int batadv_recv_bcast_packet(struct sk_buff *skb, | |
1131 | struct batadv_hard_iface *recv_if) | |
1132 | { | |
1133 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
1134 | struct batadv_orig_node *orig_node = NULL; | |
1135 | struct batadv_bcast_packet *bcast_packet; | |
1136 | struct ethhdr *ethhdr; | |
1137 | int hdr_size = sizeof(*bcast_packet); | |
1138 | int ret = NET_RX_DROP; | |
1139 | int32_t seq_diff; | |
1140 | ||
1141 | /* drop packet if it has not necessary minimum size */ | |
1142 | if (unlikely(!pskb_may_pull(skb, hdr_size))) | |
1143 | goto out; | |
1144 | ||
1145 | ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
1146 | ||
1147 | /* packet with broadcast indication but unicast recipient */ | |
1148 | if (!is_broadcast_ether_addr(ethhdr->h_dest)) | |
1149 | goto out; | |
1150 | ||
1151 | /* packet with broadcast sender address */ | |
1152 | if (is_broadcast_ether_addr(ethhdr->h_source)) | |
1153 | goto out; | |
1154 | ||
1155 | /* ignore broadcasts sent by myself */ | |
1156 | if (batadv_is_my_mac(bat_priv, ethhdr->h_source)) | |
1157 | goto out; | |
1158 | ||
1159 | bcast_packet = (struct batadv_bcast_packet *)skb->data; | |
1160 | ||
1161 | /* ignore broadcasts originated by myself */ | |
1162 | if (batadv_is_my_mac(bat_priv, bcast_packet->orig)) | |
1163 | goto out; | |
1164 | ||
1165 | if (bcast_packet->header.ttl < 2) | |
1166 | goto out; | |
1167 | ||
1168 | orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig); | |
1169 | ||
1170 | if (!orig_node) | |
1171 | goto out; | |
1172 | ||
1173 | spin_lock_bh(&orig_node->bcast_seqno_lock); | |
1174 | ||
1175 | /* check whether the packet is a duplicate */ | |
1176 | if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno, | |
1177 | ntohl(bcast_packet->seqno))) | |
1178 | goto spin_unlock; | |
1179 | ||
1180 | seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno; | |
1181 | ||
1182 | /* check whether the packet is old and the host just restarted. */ | |
1183 | if (batadv_window_protected(bat_priv, seq_diff, | |
1184 | &orig_node->bcast_seqno_reset)) | |
1185 | goto spin_unlock; | |
1186 | ||
1187 | /* mark broadcast in flood history, update window position | |
1188 | * if required. | |
1189 | */ | |
1190 | if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1)) | |
1191 | orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno); | |
1192 | ||
1193 | spin_unlock_bh(&orig_node->bcast_seqno_lock); | |
1194 | ||
1195 | /* check whether this has been sent by another originator before */ | |
1196 | if (batadv_bla_check_bcast_duplist(bat_priv, skb)) | |
1197 | goto out; | |
1198 | ||
1199 | /* rebroadcast packet */ | |
1200 | batadv_add_bcast_packet_to_list(bat_priv, skb, 1); | |
1201 | ||
1202 | /* don't hand the broadcast up if it is from an originator | |
1203 | * from the same backbone. | |
1204 | */ | |
1205 | if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size)) | |
1206 | goto out; | |
1207 | ||
1208 | if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size)) | |
1209 | goto rx_success; | |
1210 | if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size)) | |
1211 | goto rx_success; | |
1212 | ||
1213 | /* broadcast for me */ | |
1214 | batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, | |
1215 | orig_node); | |
1216 | ||
1217 | rx_success: | |
1218 | ret = NET_RX_SUCCESS; | |
1219 | goto out; | |
1220 | ||
1221 | spin_unlock: | |
1222 | spin_unlock_bh(&orig_node->bcast_seqno_lock); | |
1223 | out: | |
1224 | if (orig_node) | |
1225 | batadv_orig_node_free_ref(orig_node); | |
1226 | return ret; | |
1227 | } | |
1228 | ||
1229 | int batadv_recv_vis_packet(struct sk_buff *skb, | |
1230 | struct batadv_hard_iface *recv_if) | |
1231 | { | |
1232 | struct batadv_vis_packet *vis_packet; | |
1233 | struct ethhdr *ethhdr; | |
1234 | struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); | |
1235 | int hdr_size = sizeof(*vis_packet); | |
1236 | ||
1237 | /* keep skb linear */ | |
1238 | if (skb_linearize(skb) < 0) | |
1239 | return NET_RX_DROP; | |
1240 | ||
1241 | if (unlikely(!pskb_may_pull(skb, hdr_size))) | |
1242 | return NET_RX_DROP; | |
1243 | ||
1244 | vis_packet = (struct batadv_vis_packet *)skb->data; | |
1245 | ethhdr = (struct ethhdr *)skb_mac_header(skb); | |
1246 | ||
1247 | /* not for me */ | |
1248 | if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest)) | |
1249 | return NET_RX_DROP; | |
1250 | ||
1251 | /* ignore own packets */ | |
1252 | if (batadv_is_my_mac(bat_priv, vis_packet->vis_orig)) | |
1253 | return NET_RX_DROP; | |
1254 | ||
1255 | if (batadv_is_my_mac(bat_priv, vis_packet->sender_orig)) | |
1256 | return NET_RX_DROP; | |
1257 | ||
1258 | switch (vis_packet->vis_type) { | |
1259 | case BATADV_VIS_TYPE_SERVER_SYNC: | |
1260 | batadv_receive_server_sync_packet(bat_priv, vis_packet, | |
1261 | skb_headlen(skb)); | |
1262 | break; | |
1263 | ||
1264 | case BATADV_VIS_TYPE_CLIENT_UPDATE: | |
1265 | batadv_receive_client_update_packet(bat_priv, vis_packet, | |
1266 | skb_headlen(skb)); | |
1267 | break; | |
1268 | ||
1269 | default: /* ignore unknown packet */ | |
1270 | break; | |
1271 | } | |
1272 | ||
1273 | /* We take a copy of the data in the packet, so we should | |
1274 | * always free the skbuf. | |
1275 | */ | |
1276 | return NET_RX_DROP; | |
1277 | } |