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"
44 #include "network-coding.h"
45 #include "originator.h"
48 #include "soft-interface.h"
50 #include "translation-table.h"
53 static int batadv_route_unicast_packet(struct sk_buff *skb,
54 struct batadv_hard_iface *recv_if);
57 * _batadv_update_route - set the router for this originator
58 * @bat_priv: the bat priv with all the soft interface information
59 * @orig_node: orig node which is to be configured
60 * @recv_if: the receive interface for which this route is set
61 * @neigh_node: neighbor which should be the next router
63 * This function does not perform any error checks
65 static void _batadv_update_route(struct batadv_priv *bat_priv,
66 struct batadv_orig_node *orig_node,
67 struct batadv_hard_iface *recv_if,
68 struct batadv_neigh_node *neigh_node)
70 struct batadv_orig_ifinfo *orig_ifinfo;
71 struct batadv_neigh_node *curr_router;
73 orig_ifinfo = batadv_orig_ifinfo_get(orig_node, recv_if);
77 spin_lock_bh(&orig_node->neigh_list_lock);
78 /* curr_router used earlier may not be the current orig_ifinfo->router
79 * anymore because it was dereferenced outside of the neigh_list_lock
80 * protected region. After the new best neighbor has replace the current
81 * best neighbor the reference counter needs to decrease. Consequently,
82 * the code needs to ensure the curr_router variable contains a pointer
83 * to the replaced best neighbor.
85 curr_router = rcu_dereference_protected(orig_ifinfo->router, true);
87 /* increase refcount of new best neighbor */
89 kref_get(&neigh_node->refcount);
91 rcu_assign_pointer(orig_ifinfo->router, neigh_node);
92 spin_unlock_bh(&orig_node->neigh_list_lock);
93 batadv_orig_ifinfo_put(orig_ifinfo);
96 if ((curr_router) && (!neigh_node)) {
97 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
98 "Deleting route towards: %pM\n", orig_node->orig);
99 batadv_tt_global_del_orig(bat_priv, orig_node, -1,
100 "Deleted route towards originator");
103 } else if ((!curr_router) && (neigh_node)) {
104 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
105 "Adding route towards: %pM (via %pM)\n",
106 orig_node->orig, neigh_node->addr);
108 } else if (neigh_node && curr_router) {
109 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
110 "Changing route towards: %pM (now via %pM - was via %pM)\n",
111 orig_node->orig, neigh_node->addr,
115 /* decrease refcount of previous best neighbor */
117 batadv_neigh_node_put(curr_router);
121 * batadv_update_route - set the router for this originator
122 * @bat_priv: the bat priv with all the soft interface information
123 * @orig_node: orig node which is to be configured
124 * @recv_if: the receive interface for which this route is set
125 * @neigh_node: neighbor which should be the next router
127 void batadv_update_route(struct batadv_priv *bat_priv,
128 struct batadv_orig_node *orig_node,
129 struct batadv_hard_iface *recv_if,
130 struct batadv_neigh_node *neigh_node)
132 struct batadv_neigh_node *router = NULL;
137 router = batadv_orig_router_get(orig_node, recv_if);
139 if (router != neigh_node)
140 _batadv_update_route(bat_priv, orig_node, recv_if, neigh_node);
144 batadv_neigh_node_put(router);
148 * batadv_window_protected - checks whether the host restarted and is in the
150 * @bat_priv: the bat priv with all the soft interface information
151 * @seq_num_diff: difference between the current/received sequence number and
152 * the last sequence number
153 * @seq_old_max_diff: maximum age of sequence number not considered as restart
154 * @last_reset: jiffies timestamp of the last reset, will be updated when reset
156 * @protection_started: is set to true if the protection window was started,
157 * doesn't change otherwise.
160 * false if the packet is to be accepted.
161 * true if the packet is to be ignored.
163 bool batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
164 s32 seq_old_max_diff, unsigned long *last_reset,
165 bool *protection_started)
167 if (seq_num_diff <= -seq_old_max_diff ||
168 seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
169 if (!batadv_has_timed_out(*last_reset,
170 BATADV_RESET_PROTECTION_MS))
173 *last_reset = jiffies;
174 if (protection_started)
175 *protection_started = true;
176 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
177 "old packet received, start protection\n");
183 bool batadv_check_management_packet(struct sk_buff *skb,
184 struct batadv_hard_iface *hard_iface,
187 struct ethhdr *ethhdr;
189 /* drop packet if it has not necessary minimum size */
190 if (unlikely(!pskb_may_pull(skb, header_len)))
193 ethhdr = eth_hdr(skb);
195 /* packet with broadcast indication but unicast recipient */
196 if (!is_broadcast_ether_addr(ethhdr->h_dest))
199 /* packet with broadcast sender address */
200 if (is_broadcast_ether_addr(ethhdr->h_source))
203 /* create a copy of the skb, if needed, to modify it. */
204 if (skb_cow(skb, 0) < 0)
207 /* keep skb linear */
208 if (skb_linearize(skb) < 0)
215 * batadv_recv_my_icmp_packet - receive an icmp packet locally
216 * @bat_priv: the bat priv with all the soft interface information
217 * @skb: icmp packet to process
219 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
222 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
225 struct batadv_hard_iface *primary_if = NULL;
226 struct batadv_orig_node *orig_node = NULL;
227 struct batadv_icmp_header *icmph;
228 int res, ret = NET_RX_DROP;
230 icmph = (struct batadv_icmp_header *)skb->data;
232 switch (icmph->msg_type) {
233 case BATADV_ECHO_REPLY:
234 case BATADV_DESTINATION_UNREACHABLE:
235 case BATADV_TTL_EXCEEDED:
236 /* receive the packet */
237 if (skb_linearize(skb) < 0)
240 batadv_socket_receive_packet(icmph, skb->len);
242 case BATADV_ECHO_REQUEST:
243 /* answer echo request (ping) */
244 primary_if = batadv_primary_if_get_selected(bat_priv);
248 /* get routing information */
249 orig_node = batadv_orig_hash_find(bat_priv, icmph->orig);
253 /* create a copy of the skb, if needed, to modify it. */
254 if (skb_cow(skb, ETH_HLEN) < 0)
257 icmph = (struct batadv_icmp_header *)skb->data;
259 ether_addr_copy(icmph->dst, icmph->orig);
260 ether_addr_copy(icmph->orig, primary_if->net_dev->dev_addr);
261 icmph->msg_type = BATADV_ECHO_REPLY;
262 icmph->ttl = BATADV_TTL;
264 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
268 ret = NET_RX_SUCCESS;
272 if (!pskb_may_pull(skb, sizeof(struct batadv_icmp_tp_packet)))
275 batadv_tp_meter_recv(bat_priv, skb);
276 ret = NET_RX_SUCCESS;
279 /* drop unknown type */
284 batadv_hardif_put(primary_if);
286 batadv_orig_node_put(orig_node);
290 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
293 struct batadv_hard_iface *primary_if = NULL;
294 struct batadv_orig_node *orig_node = NULL;
295 struct batadv_icmp_packet *icmp_packet;
296 int res, ret = NET_RX_DROP;
298 icmp_packet = (struct batadv_icmp_packet *)skb->data;
300 /* send TTL exceeded if packet is an echo request (traceroute) */
301 if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
302 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
303 icmp_packet->orig, icmp_packet->dst);
307 primary_if = batadv_primary_if_get_selected(bat_priv);
311 /* get routing information */
312 orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
316 /* create a copy of the skb, if needed, to modify it. */
317 if (skb_cow(skb, ETH_HLEN) < 0)
320 icmp_packet = (struct batadv_icmp_packet *)skb->data;
322 ether_addr_copy(icmp_packet->dst, icmp_packet->orig);
323 ether_addr_copy(icmp_packet->orig, primary_if->net_dev->dev_addr);
324 icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
325 icmp_packet->ttl = BATADV_TTL;
327 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
329 ret = NET_RX_SUCCESS;
333 batadv_hardif_put(primary_if);
335 batadv_orig_node_put(orig_node);
339 int batadv_recv_icmp_packet(struct sk_buff *skb,
340 struct batadv_hard_iface *recv_if)
342 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
343 struct batadv_icmp_header *icmph;
344 struct batadv_icmp_packet_rr *icmp_packet_rr;
345 struct ethhdr *ethhdr;
346 struct batadv_orig_node *orig_node = NULL;
347 int hdr_size = sizeof(struct batadv_icmp_header);
348 int res, ret = NET_RX_DROP;
350 /* drop packet if it has not necessary minimum size */
351 if (unlikely(!pskb_may_pull(skb, hdr_size)))
354 ethhdr = eth_hdr(skb);
356 /* packet with unicast indication but broadcast recipient */
357 if (is_broadcast_ether_addr(ethhdr->h_dest))
360 /* packet with broadcast sender address */
361 if (is_broadcast_ether_addr(ethhdr->h_source))
365 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
368 icmph = (struct batadv_icmp_header *)skb->data;
370 /* add record route information if not full */
371 if ((icmph->msg_type == BATADV_ECHO_REPLY ||
372 icmph->msg_type == BATADV_ECHO_REQUEST) &&
373 (skb->len >= sizeof(struct batadv_icmp_packet_rr))) {
374 if (skb_linearize(skb) < 0)
377 /* create a copy of the skb, if needed, to modify it. */
378 if (skb_cow(skb, ETH_HLEN) < 0)
381 ethhdr = eth_hdr(skb);
382 icmph = (struct batadv_icmp_header *)skb->data;
383 icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmph;
384 if (icmp_packet_rr->rr_cur >= BATADV_RR_LEN)
387 ether_addr_copy(icmp_packet_rr->rr[icmp_packet_rr->rr_cur],
389 icmp_packet_rr->rr_cur++;
393 if (batadv_is_my_mac(bat_priv, icmph->dst))
394 return batadv_recv_my_icmp_packet(bat_priv, skb);
398 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
400 /* get routing information */
401 orig_node = batadv_orig_hash_find(bat_priv, icmph->dst);
405 /* create a copy of the skb, if needed, to modify it. */
406 if (skb_cow(skb, ETH_HLEN) < 0)
409 icmph = (struct batadv_icmp_header *)skb->data;
415 res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
417 ret = NET_RX_SUCCESS;
421 batadv_orig_node_put(orig_node);
426 * batadv_check_unicast_packet - Check for malformed unicast packets
427 * @bat_priv: the bat priv with all the soft interface information
428 * @skb: packet to check
429 * @hdr_size: size of header to pull
431 * Check for short header and bad addresses in given packet.
433 * Return: negative value when check fails and 0 otherwise. The negative value
434 * depends on the reason: -ENODATA for bad header, -EBADR for broadcast
435 * destination or source, and -EREMOTE for non-local (other host) destination.
437 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
438 struct sk_buff *skb, int hdr_size)
440 struct ethhdr *ethhdr;
442 /* drop packet if it has not necessary minimum size */
443 if (unlikely(!pskb_may_pull(skb, hdr_size)))
446 ethhdr = eth_hdr(skb);
448 /* packet with unicast indication but broadcast recipient */
449 if (is_broadcast_ether_addr(ethhdr->h_dest))
452 /* packet with broadcast sender address */
453 if (is_broadcast_ether_addr(ethhdr->h_source))
457 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
464 * batadv_last_bonding_replace - Replace last_bonding_candidate of orig_node
465 * @orig_node: originator node whose bonding candidates should be replaced
466 * @new_candidate: new bonding candidate or NULL
469 batadv_last_bonding_replace(struct batadv_orig_node *orig_node,
470 struct batadv_orig_ifinfo *new_candidate)
472 struct batadv_orig_ifinfo *old_candidate;
474 spin_lock_bh(&orig_node->neigh_list_lock);
475 old_candidate = orig_node->last_bonding_candidate;
478 kref_get(&new_candidate->refcount);
479 orig_node->last_bonding_candidate = new_candidate;
480 spin_unlock_bh(&orig_node->neigh_list_lock);
483 batadv_orig_ifinfo_put(old_candidate);
487 * batadv_find_router - find a suitable router for this originator
488 * @bat_priv: the bat priv with all the soft interface information
489 * @orig_node: the destination node
490 * @recv_if: pointer to interface this packet was received on
492 * Return: the router which should be used for this orig_node on
493 * this interface, or NULL if not available.
495 struct batadv_neigh_node *
496 batadv_find_router(struct batadv_priv *bat_priv,
497 struct batadv_orig_node *orig_node,
498 struct batadv_hard_iface *recv_if)
500 struct batadv_algo_ops *bao = bat_priv->algo_ops;
501 struct batadv_neigh_node *first_candidate_router = NULL;
502 struct batadv_neigh_node *next_candidate_router = NULL;
503 struct batadv_neigh_node *router, *cand_router = NULL;
504 struct batadv_neigh_node *last_cand_router = NULL;
505 struct batadv_orig_ifinfo *cand, *first_candidate = NULL;
506 struct batadv_orig_ifinfo *next_candidate = NULL;
507 struct batadv_orig_ifinfo *last_candidate;
508 bool last_candidate_found = false;
513 router = batadv_orig_router_get(orig_node, recv_if);
518 /* only consider bonding for recv_if == BATADV_IF_DEFAULT (first hop)
521 if (!(recv_if == BATADV_IF_DEFAULT && atomic_read(&bat_priv->bonding)))
524 /* bonding: loop through the list of possible routers found
525 * for the various outgoing interfaces and find a candidate after
526 * the last chosen bonding candidate (next_candidate). If no such
527 * router is found, use the first candidate found (the previously
528 * chosen bonding candidate might have been the last one in the list).
529 * If this can't be found either, return the previously chosen
530 * router - obviously there are no other candidates.
533 last_candidate = orig_node->last_bonding_candidate;
535 last_cand_router = rcu_dereference(last_candidate->router);
537 hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) {
538 /* acquire some structures and references ... */
539 if (!kref_get_unless_zero(&cand->refcount))
542 cand_router = rcu_dereference(cand->router);
546 if (!kref_get_unless_zero(&cand_router->refcount)) {
551 /* alternative candidate should be good enough to be
554 if (!bao->neigh.is_similar_or_better(cand_router,
555 cand->if_outgoing, router,
559 /* don't use the same router twice */
560 if (last_cand_router == cand_router)
563 /* mark the first possible candidate */
564 if (!first_candidate) {
565 kref_get(&cand_router->refcount);
566 kref_get(&cand->refcount);
567 first_candidate = cand;
568 first_candidate_router = cand_router;
571 /* check if the loop has already passed the previously selected
572 * candidate ... this function should select the next candidate
573 * AFTER the previously used bonding candidate.
575 if (!last_candidate || last_candidate_found) {
576 next_candidate = cand;
577 next_candidate_router = cand_router;
581 if (last_candidate == cand)
582 last_candidate_found = true;
584 /* free references */
586 batadv_neigh_node_put(cand_router);
589 batadv_orig_ifinfo_put(cand);
593 /* After finding candidates, handle the three cases:
594 * 1) there is a next candidate, use that
595 * 2) there is no next candidate, use the first of the list
596 * 3) there is no candidate at all, return the default router
598 if (next_candidate) {
599 batadv_neigh_node_put(router);
601 kref_get(&next_candidate_router->refcount);
602 router = next_candidate_router;
603 batadv_last_bonding_replace(orig_node, next_candidate);
604 } else if (first_candidate) {
605 batadv_neigh_node_put(router);
607 kref_get(&first_candidate_router->refcount);
608 router = first_candidate_router;
609 batadv_last_bonding_replace(orig_node, first_candidate);
611 batadv_last_bonding_replace(orig_node, NULL);
614 /* cleanup of candidates */
615 if (first_candidate) {
616 batadv_neigh_node_put(first_candidate_router);
617 batadv_orig_ifinfo_put(first_candidate);
620 if (next_candidate) {
621 batadv_neigh_node_put(next_candidate_router);
622 batadv_orig_ifinfo_put(next_candidate);
628 static int batadv_route_unicast_packet(struct sk_buff *skb,
629 struct batadv_hard_iface *recv_if)
631 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
632 struct batadv_orig_node *orig_node = NULL;
633 struct batadv_unicast_packet *unicast_packet;
634 struct ethhdr *ethhdr = eth_hdr(skb);
635 int res, hdr_len, ret = NET_RX_DROP;
638 unicast_packet = (struct batadv_unicast_packet *)skb->data;
641 if (unicast_packet->ttl < 2) {
642 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
643 ethhdr->h_source, unicast_packet->dest);
647 /* get routing information */
648 orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
653 /* create a copy of the skb, if needed, to modify it. */
654 if (skb_cow(skb, ETH_HLEN) < 0)
658 unicast_packet = (struct batadv_unicast_packet *)skb->data;
659 unicast_packet->ttl--;
661 switch (unicast_packet->packet_type) {
662 case BATADV_UNICAST_4ADDR:
663 hdr_len = sizeof(struct batadv_unicast_4addr_packet);
666 hdr_len = sizeof(struct batadv_unicast_packet);
669 /* other packet types not supported - yet */
675 batadv_skb_set_priority(skb, hdr_len);
678 res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
682 /* translate transmit result into receive result */
683 if (res == NET_XMIT_SUCCESS) {
684 /* skb was transmitted and consumed */
685 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
686 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
690 ret = NET_RX_SUCCESS;
694 batadv_orig_node_put(orig_node);
699 * batadv_reroute_unicast_packet - update the unicast header for re-routing
700 * @bat_priv: the bat priv with all the soft interface information
701 * @unicast_packet: the unicast header to be updated
702 * @dst_addr: the payload destination
703 * @vid: VLAN identifier
705 * Search the translation table for dst_addr and update the unicast header with
706 * the new corresponding information (originator address where the destination
707 * client currently is and its known TTVN)
709 * Return: true if the packet header has been updated, false otherwise
712 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
713 struct batadv_unicast_packet *unicast_packet,
714 u8 *dst_addr, unsigned short vid)
716 struct batadv_orig_node *orig_node = NULL;
717 struct batadv_hard_iface *primary_if = NULL;
719 u8 *orig_addr, orig_ttvn;
721 if (batadv_is_my_client(bat_priv, dst_addr, vid)) {
722 primary_if = batadv_primary_if_get_selected(bat_priv);
725 orig_addr = primary_if->net_dev->dev_addr;
726 orig_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
728 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr,
733 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
736 orig_addr = orig_node->orig;
737 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
740 /* update the packet header */
741 ether_addr_copy(unicast_packet->dest, orig_addr);
742 unicast_packet->ttvn = orig_ttvn;
747 batadv_hardif_put(primary_if);
749 batadv_orig_node_put(orig_node);
754 static bool batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
755 struct sk_buff *skb, int hdr_len)
757 struct batadv_unicast_packet *unicast_packet;
758 struct batadv_hard_iface *primary_if;
759 struct batadv_orig_node *orig_node;
760 u8 curr_ttvn, old_ttvn;
761 struct ethhdr *ethhdr;
765 /* check if there is enough data before accessing it */
766 if (!pskb_may_pull(skb, hdr_len + ETH_HLEN))
769 /* create a copy of the skb (in case of for re-routing) to modify it. */
770 if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
773 unicast_packet = (struct batadv_unicast_packet *)skb->data;
774 vid = batadv_get_vid(skb, hdr_len);
775 ethhdr = (struct ethhdr *)(skb->data + hdr_len);
777 /* check if the destination client was served by this node and it is now
778 * roaming. In this case, it means that the node has got a ROAM_ADV
779 * message and that it knows the new destination in the mesh to re-route
782 if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest, vid)) {
783 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
784 ethhdr->h_dest, vid))
785 batadv_dbg_ratelimited(BATADV_DBG_TT,
787 "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
788 unicast_packet->dest,
790 /* at this point the mesh destination should have been
791 * substituted with the originator address found in the global
792 * table. If not, let the packet go untouched anyway because
793 * there is nothing the node can do
798 /* retrieve the TTVN known by this node for the packet destination. This
799 * value is used later to check if the node which sent (or re-routed
800 * last time) the packet had an updated information or not
802 curr_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
803 if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
804 orig_node = batadv_orig_hash_find(bat_priv,
805 unicast_packet->dest);
806 /* if it is not possible to find the orig_node representing the
807 * destination, the packet can immediately be dropped as it will
808 * not be possible to deliver it
813 curr_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
814 batadv_orig_node_put(orig_node);
817 /* check if the TTVN contained in the packet is fresher than what the
820 is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
824 old_ttvn = unicast_packet->ttvn;
825 /* the packet was forged based on outdated network information. Its
826 * destination can possibly be updated and forwarded towards the new
829 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
830 ethhdr->h_dest, vid)) {
831 batadv_dbg_ratelimited(BATADV_DBG_TT, bat_priv,
832 "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
833 unicast_packet->dest, ethhdr->h_dest,
834 old_ttvn, curr_ttvn);
838 /* the packet has not been re-routed: either the destination is
839 * currently served by this node or there is no destination at all and
840 * it is possible to drop the packet
842 if (!batadv_is_my_client(bat_priv, ethhdr->h_dest, vid))
845 /* update the header in order to let the packet be delivered to this
846 * node's soft interface
848 primary_if = batadv_primary_if_get_selected(bat_priv);
852 ether_addr_copy(unicast_packet->dest, primary_if->net_dev->dev_addr);
854 batadv_hardif_put(primary_if);
856 unicast_packet->ttvn = curr_ttvn;
862 * batadv_recv_unhandled_unicast_packet - receive and process packets which
863 * are in the unicast number space but not yet known to the implementation
864 * @skb: unicast tvlv packet to process
865 * @recv_if: pointer to interface this packet was received on
867 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
870 int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
871 struct batadv_hard_iface *recv_if)
873 struct batadv_unicast_packet *unicast_packet;
874 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
875 int check, hdr_size = sizeof(*unicast_packet);
877 check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
881 /* we don't know about this type, drop it. */
882 unicast_packet = (struct batadv_unicast_packet *)skb->data;
883 if (batadv_is_my_mac(bat_priv, unicast_packet->dest))
886 return batadv_route_unicast_packet(skb, recv_if);
889 int batadv_recv_unicast_packet(struct sk_buff *skb,
890 struct batadv_hard_iface *recv_if)
892 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
893 struct batadv_unicast_packet *unicast_packet;
894 struct batadv_unicast_4addr_packet *unicast_4addr_packet;
896 struct batadv_orig_node *orig_node = NULL;
897 int check, hdr_size = sizeof(*unicast_packet);
898 enum batadv_subtype subtype;
901 unicast_packet = (struct batadv_unicast_packet *)skb->data;
902 unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
904 is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
905 /* the caller function should have already pulled 2 bytes */
907 hdr_size = sizeof(*unicast_4addr_packet);
909 /* function returns -EREMOTE for promiscuous packets */
910 check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
912 /* Even though the packet is not for us, we might save it to use for
913 * decoding a later received coded packet
915 if (check == -EREMOTE)
916 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
920 if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
924 if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
926 subtype = unicast_4addr_packet->subtype;
927 batadv_dat_inc_counter(bat_priv, subtype);
929 /* Only payload data should be considered for speedy
930 * join. For example, DAT also uses unicast 4addr
931 * types, but those packets should not be considered
932 * for speedy join, since the clients do not actually
933 * reside at the sending originator.
935 if (subtype == BATADV_P_DATA) {
936 orig_addr = unicast_4addr_packet->src;
937 orig_node = batadv_orig_hash_find(bat_priv,
942 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
945 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
949 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size,
954 batadv_orig_node_put(orig_node);
956 return NET_RX_SUCCESS;
959 return batadv_route_unicast_packet(skb, recv_if);
963 * batadv_recv_unicast_tvlv - receive and process unicast tvlv packets
964 * @skb: unicast tvlv packet to process
965 * @recv_if: pointer to interface this packet was received on
967 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
970 int batadv_recv_unicast_tvlv(struct sk_buff *skb,
971 struct batadv_hard_iface *recv_if)
973 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
974 struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
975 unsigned char *tvlv_buff;
977 int hdr_size = sizeof(*unicast_tvlv_packet);
978 int ret = NET_RX_DROP;
980 if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
983 /* the header is likely to be modified while forwarding */
984 if (skb_cow(skb, hdr_size) < 0)
987 /* packet needs to be linearized to access the tvlv content */
988 if (skb_linearize(skb) < 0)
991 unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)skb->data;
993 tvlv_buff = (unsigned char *)(skb->data + hdr_size);
994 tvlv_buff_len = ntohs(unicast_tvlv_packet->tvlv_len);
996 if (tvlv_buff_len > skb->len - hdr_size)
999 ret = batadv_tvlv_containers_process(bat_priv, false, NULL,
1000 unicast_tvlv_packet->src,
1001 unicast_tvlv_packet->dst,
1002 tvlv_buff, tvlv_buff_len);
1004 if (ret != NET_RX_SUCCESS)
1005 ret = batadv_route_unicast_packet(skb, recv_if);
1013 * batadv_recv_frag_packet - process received fragment
1014 * @skb: the received fragment
1015 * @recv_if: interface that the skb is received on
1017 * This function does one of the three following things: 1) Forward fragment, if
1018 * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till
1019 * lack further fragments; 3) Merge fragments, if we have all needed parts.
1021 * Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise.
1023 int batadv_recv_frag_packet(struct sk_buff *skb,
1024 struct batadv_hard_iface *recv_if)
1026 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1027 struct batadv_orig_node *orig_node_src = NULL;
1028 struct batadv_frag_packet *frag_packet;
1029 int ret = NET_RX_DROP;
1031 if (batadv_check_unicast_packet(bat_priv, skb,
1032 sizeof(*frag_packet)) < 0)
1035 frag_packet = (struct batadv_frag_packet *)skb->data;
1036 orig_node_src = batadv_orig_hash_find(bat_priv, frag_packet->orig);
1040 skb->priority = frag_packet->priority + 256;
1042 /* Route the fragment if it is not for us and too big to be merged. */
1043 if (!batadv_is_my_mac(bat_priv, frag_packet->dest) &&
1044 batadv_frag_skb_fwd(skb, recv_if, orig_node_src)) {
1045 ret = NET_RX_SUCCESS;
1049 batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_RX);
1050 batadv_add_counter(bat_priv, BATADV_CNT_FRAG_RX_BYTES, skb->len);
1052 /* Add fragment to buffer and merge if possible. */
1053 if (!batadv_frag_skb_buffer(&skb, orig_node_src))
1056 /* Deliver merged packet to the appropriate handler, if it was
1060 batadv_batman_skb_recv(skb, recv_if->net_dev,
1061 &recv_if->batman_adv_ptype, NULL);
1063 ret = NET_RX_SUCCESS;
1067 batadv_orig_node_put(orig_node_src);
1072 int batadv_recv_bcast_packet(struct sk_buff *skb,
1073 struct batadv_hard_iface *recv_if)
1075 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1076 struct batadv_orig_node *orig_node = NULL;
1077 struct batadv_bcast_packet *bcast_packet;
1078 struct ethhdr *ethhdr;
1079 int hdr_size = sizeof(*bcast_packet);
1080 int ret = NET_RX_DROP;
1084 /* drop packet if it has not necessary minimum size */
1085 if (unlikely(!pskb_may_pull(skb, hdr_size)))
1088 ethhdr = eth_hdr(skb);
1090 /* packet with broadcast indication but unicast recipient */
1091 if (!is_broadcast_ether_addr(ethhdr->h_dest))
1094 /* packet with broadcast sender address */
1095 if (is_broadcast_ether_addr(ethhdr->h_source))
1098 /* ignore broadcasts sent by myself */
1099 if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1102 bcast_packet = (struct batadv_bcast_packet *)skb->data;
1104 /* ignore broadcasts originated by myself */
1105 if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1108 if (bcast_packet->ttl < 2)
1111 orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1116 spin_lock_bh(&orig_node->bcast_seqno_lock);
1118 seqno = ntohl(bcast_packet->seqno);
1119 /* check whether the packet is a duplicate */
1120 if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1124 seq_diff = seqno - orig_node->last_bcast_seqno;
1126 /* check whether the packet is old and the host just restarted. */
1127 if (batadv_window_protected(bat_priv, seq_diff,
1128 BATADV_BCAST_MAX_AGE,
1129 &orig_node->bcast_seqno_reset, NULL))
1132 /* mark broadcast in flood history, update window position
1135 if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1136 orig_node->last_bcast_seqno = seqno;
1138 spin_unlock_bh(&orig_node->bcast_seqno_lock);
1140 /* check whether this has been sent by another originator before */
1141 if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1144 batadv_skb_set_priority(skb, sizeof(struct batadv_bcast_packet));
1146 /* rebroadcast packet */
1147 batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
1149 /* don't hand the broadcast up if it is from an originator
1150 * from the same backbone.
1152 if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1155 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1157 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1160 /* broadcast for me */
1161 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node);
1164 ret = NET_RX_SUCCESS;
1168 spin_unlock_bh(&orig_node->bcast_seqno_lock);
1171 batadv_orig_node_put(orig_node);