1 /* Copyright (C) 2007-2016 B.A.T.M.A.N. contributors:
3 * Marek Lindner, Simon Wunderlich
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.
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.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include <linux/atomic.h>
22 #include <linux/byteorder/generic.h>
23 #include <linux/compiler.h>
24 #include <linux/errno.h>
25 #include <linux/etherdevice.h>
26 #include <linux/if_ether.h>
27 #include <linux/jiffies.h>
28 #include <linux/kref.h>
29 #include <linux/netdevice.h>
30 #include <linux/printk.h>
31 #include <linux/rculist.h>
32 #include <linux/rcupdate.h>
33 #include <linux/skbuff.h>
34 #include <linux/spinlock.h>
35 #include <linux/stddef.h>
38 #include "bridge_loop_avoidance.h"
39 #include "distributed-arp-table.h"
40 #include "fragmentation.h"
41 #include "hard-interface.h"
42 #include "icmp_socket.h"
43 #include "network-coding.h"
44 #include "originator.h"
47 #include "soft-interface.h"
48 #include "translation-table.h"
50 static int batadv_route_unicast_packet(struct sk_buff *skb,
51 struct batadv_hard_iface *recv_if);
54 * _batadv_update_route - set the router for this originator
55 * @bat_priv: the bat priv with all the soft interface information
56 * @orig_node: orig node which is to be configured
57 * @recv_if: the receive interface for which this route is set
58 * @neigh_node: neighbor which should be the next router
60 * This function does not perform any error checks
62 static void _batadv_update_route(struct batadv_priv *bat_priv,
63 struct batadv_orig_node *orig_node,
64 struct batadv_hard_iface *recv_if,
65 struct batadv_neigh_node *neigh_node)
67 struct batadv_orig_ifinfo *orig_ifinfo;
68 struct batadv_neigh_node *curr_router;
70 orig_ifinfo = batadv_orig_ifinfo_get(orig_node, recv_if);
75 curr_router = rcu_dereference(orig_ifinfo->router);
76 if (curr_router && !kref_get_unless_zero(&curr_router->refcount))
81 if ((curr_router) && (!neigh_node)) {
82 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
83 "Deleting route towards: %pM\n", orig_node->orig);
84 batadv_tt_global_del_orig(bat_priv, orig_node, -1,
85 "Deleted route towards originator");
88 } else if ((!curr_router) && (neigh_node)) {
89 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
90 "Adding route towards: %pM (via %pM)\n",
91 orig_node->orig, neigh_node->addr);
93 } else if (neigh_node && curr_router) {
94 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
95 "Changing route towards: %pM (now via %pM - was via %pM)\n",
96 orig_node->orig, neigh_node->addr,
101 batadv_neigh_node_put(curr_router);
103 spin_lock_bh(&orig_node->neigh_list_lock);
104 /* curr_router used earlier may not be the current orig_ifinfo->router
105 * anymore because it was dereferenced outside of the neigh_list_lock
106 * protected region. After the new best neighbor has replace the current
107 * best neighbor the reference counter needs to decrease. Consequently,
108 * the code needs to ensure the curr_router variable contains a pointer
109 * to the replaced best neighbor.
111 curr_router = rcu_dereference_protected(orig_ifinfo->router, true);
113 /* increase refcount of new best neighbor */
115 kref_get(&neigh_node->refcount);
117 rcu_assign_pointer(orig_ifinfo->router, neigh_node);
118 spin_unlock_bh(&orig_node->neigh_list_lock);
119 batadv_orig_ifinfo_put(orig_ifinfo);
121 /* decrease refcount of previous best neighbor */
123 batadv_neigh_node_put(curr_router);
127 * batadv_update_route - set the router for this originator
128 * @bat_priv: the bat priv with all the soft interface information
129 * @orig_node: orig node which is to be configured
130 * @recv_if: the receive interface for which this route is set
131 * @neigh_node: neighbor which should be the next router
133 void batadv_update_route(struct batadv_priv *bat_priv,
134 struct batadv_orig_node *orig_node,
135 struct batadv_hard_iface *recv_if,
136 struct batadv_neigh_node *neigh_node)
138 struct batadv_neigh_node *router = NULL;
143 router = batadv_orig_router_get(orig_node, recv_if);
145 if (router != neigh_node)
146 _batadv_update_route(bat_priv, orig_node, recv_if, neigh_node);
150 batadv_neigh_node_put(router);
154 * batadv_window_protected - checks whether the host restarted and is in the
156 * @bat_priv: the bat priv with all the soft interface information
157 * @seq_num_diff: difference between the current/received sequence number and
158 * the last sequence number
159 * @seq_old_max_diff: maximum age of sequence number not considered as restart
160 * @last_reset: jiffies timestamp of the last reset, will be updated when reset
162 * @protection_started: is set to true if the protection window was started,
163 * doesn't change otherwise.
166 * false if the packet is to be accepted.
167 * true if the packet is to be ignored.
169 bool batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
170 s32 seq_old_max_diff, unsigned long *last_reset,
171 bool *protection_started)
173 if (seq_num_diff <= -seq_old_max_diff ||
174 seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
175 if (!batadv_has_timed_out(*last_reset,
176 BATADV_RESET_PROTECTION_MS))
179 *last_reset = jiffies;
180 if (protection_started)
181 *protection_started = true;
182 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
183 "old packet received, start protection\n");
189 bool batadv_check_management_packet(struct sk_buff *skb,
190 struct batadv_hard_iface *hard_iface,
193 struct ethhdr *ethhdr;
195 /* drop packet if it has not necessary minimum size */
196 if (unlikely(!pskb_may_pull(skb, header_len)))
199 ethhdr = eth_hdr(skb);
201 /* packet with broadcast indication but unicast recipient */
202 if (!is_broadcast_ether_addr(ethhdr->h_dest))
205 /* packet with broadcast sender address */
206 if (is_broadcast_ether_addr(ethhdr->h_source))
209 /* create a copy of the skb, if needed, to modify it. */
210 if (skb_cow(skb, 0) < 0)
213 /* keep skb linear */
214 if (skb_linearize(skb) < 0)
221 * batadv_recv_my_icmp_packet - receive an icmp packet locally
222 * @bat_priv: the bat priv with all the soft interface information
223 * @skb: icmp packet to process
225 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
228 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
231 struct batadv_hard_iface *primary_if = NULL;
232 struct batadv_orig_node *orig_node = NULL;
233 struct batadv_icmp_header *icmph;
234 int res, ret = NET_RX_DROP;
236 icmph = (struct batadv_icmp_header *)skb->data;
238 switch (icmph->msg_type) {
239 case BATADV_ECHO_REPLY:
240 case BATADV_DESTINATION_UNREACHABLE:
241 case BATADV_TTL_EXCEEDED:
242 /* receive the packet */
243 if (skb_linearize(skb) < 0)
246 batadv_socket_receive_packet(icmph, skb->len);
248 case BATADV_ECHO_REQUEST:
249 /* answer echo request (ping) */
250 primary_if = batadv_primary_if_get_selected(bat_priv);
254 /* get routing information */
255 orig_node = batadv_orig_hash_find(bat_priv, icmph->orig);
259 /* create a copy of the skb, if needed, to modify it. */
260 if (skb_cow(skb, ETH_HLEN) < 0)
263 icmph = (struct batadv_icmp_header *)skb->data;
265 ether_addr_copy(icmph->dst, icmph->orig);
266 ether_addr_copy(icmph->orig, primary_if->net_dev->dev_addr);
267 icmph->msg_type = BATADV_ECHO_REPLY;
268 icmph->ttl = BATADV_TTL;
270 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
271 if (res != NET_XMIT_DROP)
272 ret = NET_RX_SUCCESS;
276 /* drop unknown type */
281 batadv_hardif_put(primary_if);
283 batadv_orig_node_put(orig_node);
287 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
290 struct batadv_hard_iface *primary_if = NULL;
291 struct batadv_orig_node *orig_node = NULL;
292 struct batadv_icmp_packet *icmp_packet;
293 int ret = NET_RX_DROP;
295 icmp_packet = (struct batadv_icmp_packet *)skb->data;
297 /* send TTL exceeded if packet is an echo request (traceroute) */
298 if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
299 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
300 icmp_packet->orig, icmp_packet->dst);
304 primary_if = batadv_primary_if_get_selected(bat_priv);
308 /* get routing information */
309 orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
313 /* create a copy of the skb, if needed, to modify it. */
314 if (skb_cow(skb, ETH_HLEN) < 0)
317 icmp_packet = (struct batadv_icmp_packet *)skb->data;
319 ether_addr_copy(icmp_packet->dst, icmp_packet->orig);
320 ether_addr_copy(icmp_packet->orig, primary_if->net_dev->dev_addr);
321 icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
322 icmp_packet->ttl = BATADV_TTL;
324 if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
325 ret = NET_RX_SUCCESS;
329 batadv_hardif_put(primary_if);
331 batadv_orig_node_put(orig_node);
335 int batadv_recv_icmp_packet(struct sk_buff *skb,
336 struct batadv_hard_iface *recv_if)
338 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
339 struct batadv_icmp_header *icmph;
340 struct batadv_icmp_packet_rr *icmp_packet_rr;
341 struct ethhdr *ethhdr;
342 struct batadv_orig_node *orig_node = NULL;
343 int hdr_size = sizeof(struct batadv_icmp_header);
344 int ret = NET_RX_DROP;
346 /* drop packet if it has not necessary minimum size */
347 if (unlikely(!pskb_may_pull(skb, hdr_size)))
350 ethhdr = eth_hdr(skb);
352 /* packet with unicast indication but broadcast recipient */
353 if (is_broadcast_ether_addr(ethhdr->h_dest))
356 /* packet with broadcast sender address */
357 if (is_broadcast_ether_addr(ethhdr->h_source))
361 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
364 icmph = (struct batadv_icmp_header *)skb->data;
366 /* add record route information if not full */
367 if ((icmph->msg_type == BATADV_ECHO_REPLY ||
368 icmph->msg_type == BATADV_ECHO_REQUEST) &&
369 (skb->len >= sizeof(struct batadv_icmp_packet_rr))) {
370 if (skb_linearize(skb) < 0)
373 /* create a copy of the skb, if needed, to modify it. */
374 if (skb_cow(skb, ETH_HLEN) < 0)
377 icmph = (struct batadv_icmp_header *)skb->data;
378 icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmph;
379 if (icmp_packet_rr->rr_cur >= BATADV_RR_LEN)
382 ether_addr_copy(icmp_packet_rr->rr[icmp_packet_rr->rr_cur],
384 icmp_packet_rr->rr_cur++;
388 if (batadv_is_my_mac(bat_priv, icmph->dst))
389 return batadv_recv_my_icmp_packet(bat_priv, skb);
393 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
395 /* get routing information */
396 orig_node = batadv_orig_hash_find(bat_priv, icmph->dst);
400 /* create a copy of the skb, if needed, to modify it. */
401 if (skb_cow(skb, ETH_HLEN) < 0)
404 icmph = (struct batadv_icmp_header *)skb->data;
410 if (batadv_send_skb_to_orig(skb, orig_node, recv_if) != NET_XMIT_DROP)
411 ret = NET_RX_SUCCESS;
415 batadv_orig_node_put(orig_node);
420 * batadv_check_unicast_packet - Check for malformed unicast packets
421 * @bat_priv: the bat priv with all the soft interface information
422 * @skb: packet to check
423 * @hdr_size: size of header to pull
425 * Check for short header and bad addresses in given packet.
427 * Return: negative value when check fails and 0 otherwise. The negative value
428 * depends on the reason: -ENODATA for bad header, -EBADR for broadcast
429 * destination or source, and -EREMOTE for non-local (other host) destination.
431 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
432 struct sk_buff *skb, int hdr_size)
434 struct ethhdr *ethhdr;
436 /* drop packet if it has not necessary minimum size */
437 if (unlikely(!pskb_may_pull(skb, hdr_size)))
440 ethhdr = eth_hdr(skb);
442 /* packet with unicast indication but broadcast recipient */
443 if (is_broadcast_ether_addr(ethhdr->h_dest))
446 /* packet with broadcast sender address */
447 if (is_broadcast_ether_addr(ethhdr->h_source))
451 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
458 * batadv_find_router - find a suitable router for this originator
459 * @bat_priv: the bat priv with all the soft interface information
460 * @orig_node: the destination node
461 * @recv_if: pointer to interface this packet was received on
463 * Return: the router which should be used for this orig_node on
464 * this interface, or NULL if not available.
466 struct batadv_neigh_node *
467 batadv_find_router(struct batadv_priv *bat_priv,
468 struct batadv_orig_node *orig_node,
469 struct batadv_hard_iface *recv_if)
471 struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
472 struct batadv_neigh_node *first_candidate_router = NULL;
473 struct batadv_neigh_node *next_candidate_router = NULL;
474 struct batadv_neigh_node *router, *cand_router = NULL;
475 struct batadv_neigh_node *last_cand_router = NULL;
476 struct batadv_orig_ifinfo *cand, *first_candidate = NULL;
477 struct batadv_orig_ifinfo *next_candidate = NULL;
478 struct batadv_orig_ifinfo *last_candidate;
479 bool last_candidate_found = false;
484 router = batadv_orig_router_get(orig_node, recv_if);
489 /* only consider bonding for recv_if == BATADV_IF_DEFAULT (first hop)
492 if (!(recv_if == BATADV_IF_DEFAULT && atomic_read(&bat_priv->bonding)))
495 /* bonding: loop through the list of possible routers found
496 * for the various outgoing interfaces and find a candidate after
497 * the last chosen bonding candidate (next_candidate). If no such
498 * router is found, use the first candidate found (the previously
499 * chosen bonding candidate might have been the last one in the list).
500 * If this can't be found either, return the previously chosen
501 * router - obviously there are no other candidates.
504 last_candidate = orig_node->last_bonding_candidate;
506 last_cand_router = rcu_dereference(last_candidate->router);
508 hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) {
509 /* acquire some structures and references ... */
510 if (!kref_get_unless_zero(&cand->refcount))
513 cand_router = rcu_dereference(cand->router);
517 if (!kref_get_unless_zero(&cand_router->refcount)) {
522 /* alternative candidate should be good enough to be
525 if (!bao->bat_neigh_is_similar_or_better(cand_router,
530 /* don't use the same router twice */
531 if (last_cand_router == cand_router)
534 /* mark the first possible candidate */
535 if (!first_candidate) {
536 kref_get(&cand_router->refcount);
537 kref_get(&cand->refcount);
538 first_candidate = cand;
539 first_candidate_router = cand_router;
542 /* check if the loop has already passed the previously selected
543 * candidate ... this function should select the next candidate
544 * AFTER the previously used bonding candidate.
546 if (!last_candidate || last_candidate_found) {
547 next_candidate = cand;
548 next_candidate_router = cand_router;
552 if (last_candidate == cand)
553 last_candidate_found = true;
555 /* free references */
557 batadv_neigh_node_put(cand_router);
560 batadv_orig_ifinfo_put(cand);
564 /* last_bonding_candidate is reset below, remove the old reference. */
565 if (orig_node->last_bonding_candidate)
566 batadv_orig_ifinfo_put(orig_node->last_bonding_candidate);
568 /* After finding candidates, handle the three cases:
569 * 1) there is a next candidate, use that
570 * 2) there is no next candidate, use the first of the list
571 * 3) there is no candidate at all, return the default router
573 if (next_candidate) {
574 batadv_neigh_node_put(router);
576 /* remove references to first candidate, we don't need it. */
577 if (first_candidate) {
578 batadv_neigh_node_put(first_candidate_router);
579 batadv_orig_ifinfo_put(first_candidate);
581 router = next_candidate_router;
582 orig_node->last_bonding_candidate = next_candidate;
583 } else if (first_candidate) {
584 batadv_neigh_node_put(router);
586 /* refcounting has already been done in the loop above. */
587 router = first_candidate_router;
588 orig_node->last_bonding_candidate = first_candidate;
590 orig_node->last_bonding_candidate = NULL;
596 static int batadv_route_unicast_packet(struct sk_buff *skb,
597 struct batadv_hard_iface *recv_if)
599 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
600 struct batadv_orig_node *orig_node = NULL;
601 struct batadv_unicast_packet *unicast_packet;
602 struct ethhdr *ethhdr = eth_hdr(skb);
603 int res, hdr_len, ret = NET_RX_DROP;
606 unicast_packet = (struct batadv_unicast_packet *)skb->data;
609 if (unicast_packet->ttl < 2) {
610 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
611 ethhdr->h_source, unicast_packet->dest);
615 /* get routing information */
616 orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
621 /* create a copy of the skb, if needed, to modify it. */
622 if (skb_cow(skb, ETH_HLEN) < 0)
626 unicast_packet = (struct batadv_unicast_packet *)skb->data;
627 unicast_packet->ttl--;
629 switch (unicast_packet->packet_type) {
630 case BATADV_UNICAST_4ADDR:
631 hdr_len = sizeof(struct batadv_unicast_4addr_packet);
634 hdr_len = sizeof(struct batadv_unicast_packet);
637 /* other packet types not supported - yet */
643 batadv_skb_set_priority(skb, hdr_len);
646 res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
648 /* translate transmit result into receive result */
649 if (res == NET_XMIT_SUCCESS) {
650 /* skb was transmitted and consumed */
651 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
652 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
655 ret = NET_RX_SUCCESS;
656 } else if (res == NET_XMIT_POLICED) {
657 /* skb was buffered and consumed */
658 ret = NET_RX_SUCCESS;
663 batadv_orig_node_put(orig_node);
668 * batadv_reroute_unicast_packet - update the unicast header for re-routing
669 * @bat_priv: the bat priv with all the soft interface information
670 * @unicast_packet: the unicast header to be updated
671 * @dst_addr: the payload destination
672 * @vid: VLAN identifier
674 * Search the translation table for dst_addr and update the unicast header with
675 * the new corresponding information (originator address where the destination
676 * client currently is and its known TTVN)
678 * Return: true if the packet header has been updated, false otherwise
681 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
682 struct batadv_unicast_packet *unicast_packet,
683 u8 *dst_addr, unsigned short vid)
685 struct batadv_orig_node *orig_node = NULL;
686 struct batadv_hard_iface *primary_if = NULL;
688 u8 *orig_addr, orig_ttvn;
690 if (batadv_is_my_client(bat_priv, dst_addr, vid)) {
691 primary_if = batadv_primary_if_get_selected(bat_priv);
694 orig_addr = primary_if->net_dev->dev_addr;
695 orig_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
697 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr,
702 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
705 orig_addr = orig_node->orig;
706 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
709 /* update the packet header */
710 ether_addr_copy(unicast_packet->dest, orig_addr);
711 unicast_packet->ttvn = orig_ttvn;
716 batadv_hardif_put(primary_if);
718 batadv_orig_node_put(orig_node);
723 static bool batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
724 struct sk_buff *skb, int hdr_len)
726 struct batadv_unicast_packet *unicast_packet;
727 struct batadv_hard_iface *primary_if;
728 struct batadv_orig_node *orig_node;
729 u8 curr_ttvn, old_ttvn;
730 struct ethhdr *ethhdr;
734 /* check if there is enough data before accessing it */
735 if (!pskb_may_pull(skb, hdr_len + ETH_HLEN))
738 /* create a copy of the skb (in case of for re-routing) to modify it. */
739 if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
742 unicast_packet = (struct batadv_unicast_packet *)skb->data;
743 vid = batadv_get_vid(skb, hdr_len);
744 ethhdr = (struct ethhdr *)(skb->data + hdr_len);
746 /* check if the destination client was served by this node and it is now
747 * roaming. In this case, it means that the node has got a ROAM_ADV
748 * message and that it knows the new destination in the mesh to re-route
751 if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest, vid)) {
752 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
753 ethhdr->h_dest, vid))
754 batadv_dbg_ratelimited(BATADV_DBG_TT,
756 "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
757 unicast_packet->dest,
759 /* at this point the mesh destination should have been
760 * substituted with the originator address found in the global
761 * table. If not, let the packet go untouched anyway because
762 * there is nothing the node can do
767 /* retrieve the TTVN known by this node for the packet destination. This
768 * value is used later to check if the node which sent (or re-routed
769 * last time) the packet had an updated information or not
771 curr_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
772 if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
773 orig_node = batadv_orig_hash_find(bat_priv,
774 unicast_packet->dest);
775 /* if it is not possible to find the orig_node representing the
776 * destination, the packet can immediately be dropped as it will
777 * not be possible to deliver it
782 curr_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
783 batadv_orig_node_put(orig_node);
786 /* check if the TTVN contained in the packet is fresher than what the
789 is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
793 old_ttvn = unicast_packet->ttvn;
794 /* the packet was forged based on outdated network information. Its
795 * destination can possibly be updated and forwarded towards the new
798 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
799 ethhdr->h_dest, vid)) {
800 batadv_dbg_ratelimited(BATADV_DBG_TT, bat_priv,
801 "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
802 unicast_packet->dest, ethhdr->h_dest,
803 old_ttvn, curr_ttvn);
807 /* the packet has not been re-routed: either the destination is
808 * currently served by this node or there is no destination at all and
809 * it is possible to drop the packet
811 if (!batadv_is_my_client(bat_priv, ethhdr->h_dest, vid))
814 /* update the header in order to let the packet be delivered to this
815 * node's soft interface
817 primary_if = batadv_primary_if_get_selected(bat_priv);
821 ether_addr_copy(unicast_packet->dest, primary_if->net_dev->dev_addr);
823 batadv_hardif_put(primary_if);
825 unicast_packet->ttvn = curr_ttvn;
831 * batadv_recv_unhandled_unicast_packet - receive and process packets which
832 * are in the unicast number space but not yet known to the implementation
833 * @skb: unicast tvlv packet to process
834 * @recv_if: pointer to interface this packet was received on
836 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
839 int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
840 struct batadv_hard_iface *recv_if)
842 struct batadv_unicast_packet *unicast_packet;
843 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
844 int check, hdr_size = sizeof(*unicast_packet);
846 check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
850 /* we don't know about this type, drop it. */
851 unicast_packet = (struct batadv_unicast_packet *)skb->data;
852 if (batadv_is_my_mac(bat_priv, unicast_packet->dest))
855 return batadv_route_unicast_packet(skb, recv_if);
858 int batadv_recv_unicast_packet(struct sk_buff *skb,
859 struct batadv_hard_iface *recv_if)
861 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
862 struct batadv_unicast_packet *unicast_packet;
863 struct batadv_unicast_4addr_packet *unicast_4addr_packet;
865 struct batadv_orig_node *orig_node = NULL;
866 int check, hdr_size = sizeof(*unicast_packet);
867 enum batadv_subtype subtype;
870 unicast_packet = (struct batadv_unicast_packet *)skb->data;
871 unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
873 is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
874 /* the caller function should have already pulled 2 bytes */
876 hdr_size = sizeof(*unicast_4addr_packet);
878 /* function returns -EREMOTE for promiscuous packets */
879 check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
881 /* Even though the packet is not for us, we might save it to use for
882 * decoding a later received coded packet
884 if (check == -EREMOTE)
885 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
889 if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
893 if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
895 subtype = unicast_4addr_packet->subtype;
896 batadv_dat_inc_counter(bat_priv, subtype);
898 /* Only payload data should be considered for speedy
899 * join. For example, DAT also uses unicast 4addr
900 * types, but those packets should not be considered
901 * for speedy join, since the clients do not actually
902 * reside at the sending originator.
904 if (subtype == BATADV_P_DATA) {
905 orig_addr = unicast_4addr_packet->src;
906 orig_node = batadv_orig_hash_find(bat_priv,
911 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
914 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
918 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size,
923 batadv_orig_node_put(orig_node);
925 return NET_RX_SUCCESS;
928 return batadv_route_unicast_packet(skb, recv_if);
932 * batadv_recv_unicast_tvlv - receive and process unicast tvlv packets
933 * @skb: unicast tvlv packet to process
934 * @recv_if: pointer to interface this packet was received on
936 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
939 int batadv_recv_unicast_tvlv(struct sk_buff *skb,
940 struct batadv_hard_iface *recv_if)
942 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
943 struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
944 unsigned char *tvlv_buff;
946 int hdr_size = sizeof(*unicast_tvlv_packet);
947 int ret = NET_RX_DROP;
949 if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
952 /* the header is likely to be modified while forwarding */
953 if (skb_cow(skb, hdr_size) < 0)
956 /* packet needs to be linearized to access the tvlv content */
957 if (skb_linearize(skb) < 0)
960 unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)skb->data;
962 tvlv_buff = (unsigned char *)(skb->data + hdr_size);
963 tvlv_buff_len = ntohs(unicast_tvlv_packet->tvlv_len);
965 if (tvlv_buff_len > skb->len - hdr_size)
968 ret = batadv_tvlv_containers_process(bat_priv, false, NULL,
969 unicast_tvlv_packet->src,
970 unicast_tvlv_packet->dst,
971 tvlv_buff, tvlv_buff_len);
973 if (ret != NET_RX_SUCCESS)
974 ret = batadv_route_unicast_packet(skb, recv_if);
982 * batadv_recv_frag_packet - process received fragment
983 * @skb: the received fragment
984 * @recv_if: interface that the skb is received on
986 * This function does one of the three following things: 1) Forward fragment, if
987 * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till
988 * lack further fragments; 3) Merge fragments, if we have all needed parts.
990 * Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise.
992 int batadv_recv_frag_packet(struct sk_buff *skb,
993 struct batadv_hard_iface *recv_if)
995 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
996 struct batadv_orig_node *orig_node_src = NULL;
997 struct batadv_frag_packet *frag_packet;
998 int ret = NET_RX_DROP;
1000 if (batadv_check_unicast_packet(bat_priv, skb,
1001 sizeof(*frag_packet)) < 0)
1004 frag_packet = (struct batadv_frag_packet *)skb->data;
1005 orig_node_src = batadv_orig_hash_find(bat_priv, frag_packet->orig);
1009 /* Route the fragment if it is not for us and too big to be merged. */
1010 if (!batadv_is_my_mac(bat_priv, frag_packet->dest) &&
1011 batadv_frag_skb_fwd(skb, recv_if, orig_node_src)) {
1012 ret = NET_RX_SUCCESS;
1016 batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_RX);
1017 batadv_add_counter(bat_priv, BATADV_CNT_FRAG_RX_BYTES, skb->len);
1019 /* Add fragment to buffer and merge if possible. */
1020 if (!batadv_frag_skb_buffer(&skb, orig_node_src))
1023 /* Deliver merged packet to the appropriate handler, if it was
1027 batadv_batman_skb_recv(skb, recv_if->net_dev,
1028 &recv_if->batman_adv_ptype, NULL);
1030 ret = NET_RX_SUCCESS;
1034 batadv_orig_node_put(orig_node_src);
1039 int batadv_recv_bcast_packet(struct sk_buff *skb,
1040 struct batadv_hard_iface *recv_if)
1042 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1043 struct batadv_orig_node *orig_node = NULL;
1044 struct batadv_bcast_packet *bcast_packet;
1045 struct ethhdr *ethhdr;
1046 int hdr_size = sizeof(*bcast_packet);
1047 int ret = NET_RX_DROP;
1051 /* drop packet if it has not necessary minimum size */
1052 if (unlikely(!pskb_may_pull(skb, hdr_size)))
1055 ethhdr = eth_hdr(skb);
1057 /* packet with broadcast indication but unicast recipient */
1058 if (!is_broadcast_ether_addr(ethhdr->h_dest))
1061 /* packet with broadcast sender address */
1062 if (is_broadcast_ether_addr(ethhdr->h_source))
1065 /* ignore broadcasts sent by myself */
1066 if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1069 bcast_packet = (struct batadv_bcast_packet *)skb->data;
1071 /* ignore broadcasts originated by myself */
1072 if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1075 if (bcast_packet->ttl < 2)
1078 orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1083 spin_lock_bh(&orig_node->bcast_seqno_lock);
1085 seqno = ntohl(bcast_packet->seqno);
1086 /* check whether the packet is a duplicate */
1087 if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1091 seq_diff = seqno - orig_node->last_bcast_seqno;
1093 /* check whether the packet is old and the host just restarted. */
1094 if (batadv_window_protected(bat_priv, seq_diff,
1095 BATADV_BCAST_MAX_AGE,
1096 &orig_node->bcast_seqno_reset, NULL))
1099 /* mark broadcast in flood history, update window position
1102 if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1103 orig_node->last_bcast_seqno = seqno;
1105 spin_unlock_bh(&orig_node->bcast_seqno_lock);
1107 /* check whether this has been sent by another originator before */
1108 if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1111 batadv_skb_set_priority(skb, sizeof(struct batadv_bcast_packet));
1113 /* rebroadcast packet */
1114 batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
1116 /* don't hand the broadcast up if it is from an originator
1117 * from the same backbone.
1119 if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1122 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1124 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1127 /* broadcast for me */
1128 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node);
1131 ret = NET_RX_SUCCESS;
1135 spin_unlock_bh(&orig_node->bcast_seqno_lock);
1138 batadv_orig_node_put(orig_node);