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[linux/fpc-iii.git] / net / batman-adv / send.c
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1 /* Copyright (C) 2007-2017 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/>.
18 #include "send.h"
19 #include "main.h"
21 #include <linux/atomic.h>
22 #include <linux/bug.h>
23 #include <linux/byteorder/generic.h>
24 #include <linux/errno.h>
25 #include <linux/etherdevice.h>
26 #include <linux/fs.h>
27 #include <linux/if.h>
28 #include <linux/if_ether.h>
29 #include <linux/jiffies.h>
30 #include <linux/kernel.h>
31 #include <linux/kref.h>
32 #include <linux/list.h>
33 #include <linux/netdevice.h>
34 #include <linux/printk.h>
35 #include <linux/rculist.h>
36 #include <linux/rcupdate.h>
37 #include <linux/skbuff.h>
38 #include <linux/slab.h>
39 #include <linux/spinlock.h>
40 #include <linux/stddef.h>
41 #include <linux/workqueue.h>
43 #include "distributed-arp-table.h"
44 #include "fragmentation.h"
45 #include "gateway_client.h"
46 #include "hard-interface.h"
47 #include "log.h"
48 #include "network-coding.h"
49 #include "originator.h"
50 #include "routing.h"
51 #include "soft-interface.h"
52 #include "translation-table.h"
54 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
56 /**
57 * batadv_send_skb_packet - send an already prepared packet
58 * @skb: the packet to send
59 * @hard_iface: the interface to use to send the broadcast packet
60 * @dst_addr: the payload destination
62 * Send out an already prepared packet to the given neighbor or broadcast it
63 * using the specified interface. Either hard_iface or neigh_node must be not
64 * NULL.
65 * If neigh_node is NULL, then the packet is broadcasted using hard_iface,
66 * otherwise it is sent as unicast to the given neighbor.
68 * Regardless of the return value, the skb is consumed.
70 * Return: A negative errno code is returned on a failure. A success does not
71 * guarantee the frame will be transmitted as it may be dropped due
72 * to congestion or traffic shaping.
74 int batadv_send_skb_packet(struct sk_buff *skb,
75 struct batadv_hard_iface *hard_iface,
76 const u8 *dst_addr)
78 struct batadv_priv *bat_priv;
79 struct ethhdr *ethhdr;
80 int ret;
82 bat_priv = netdev_priv(hard_iface->soft_iface);
84 if (hard_iface->if_status != BATADV_IF_ACTIVE)
85 goto send_skb_err;
87 if (unlikely(!hard_iface->net_dev))
88 goto send_skb_err;
90 if (!(hard_iface->net_dev->flags & IFF_UP)) {
91 pr_warn("Interface %s is not up - can't send packet via that interface!\n",
92 hard_iface->net_dev->name);
93 goto send_skb_err;
96 /* push to the ethernet header. */
97 if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
98 goto send_skb_err;
100 skb_reset_mac_header(skb);
102 ethhdr = eth_hdr(skb);
103 ether_addr_copy(ethhdr->h_source, hard_iface->net_dev->dev_addr);
104 ether_addr_copy(ethhdr->h_dest, dst_addr);
105 ethhdr->h_proto = htons(ETH_P_BATMAN);
107 skb_set_network_header(skb, ETH_HLEN);
108 skb->protocol = htons(ETH_P_BATMAN);
110 skb->dev = hard_iface->net_dev;
112 /* Save a clone of the skb to use when decoding coded packets */
113 batadv_nc_skb_store_for_decoding(bat_priv, skb);
115 /* dev_queue_xmit() returns a negative result on error. However on
116 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
117 * (which is > 0). This will not be treated as an error.
119 ret = dev_queue_xmit(skb);
120 return net_xmit_eval(ret);
121 send_skb_err:
122 kfree_skb(skb);
123 return NET_XMIT_DROP;
126 int batadv_send_broadcast_skb(struct sk_buff *skb,
127 struct batadv_hard_iface *hard_iface)
129 return batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
132 int batadv_send_unicast_skb(struct sk_buff *skb,
133 struct batadv_neigh_node *neigh)
135 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
136 struct batadv_hardif_neigh_node *hardif_neigh;
137 #endif
138 int ret;
140 ret = batadv_send_skb_packet(skb, neigh->if_incoming, neigh->addr);
142 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
143 hardif_neigh = batadv_hardif_neigh_get(neigh->if_incoming, neigh->addr);
145 if ((hardif_neigh) && (ret != NET_XMIT_DROP))
146 hardif_neigh->bat_v.last_unicast_tx = jiffies;
148 if (hardif_neigh)
149 batadv_hardif_neigh_put(hardif_neigh);
150 #endif
152 return ret;
156 * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
157 * @skb: Packet to be transmitted.
158 * @orig_node: Final destination of the packet.
159 * @recv_if: Interface used when receiving the packet (can be NULL).
161 * Looks up the best next-hop towards the passed originator and passes the
162 * skb on for preparation of MAC header. If the packet originated from this
163 * host, NULL can be passed as recv_if and no interface alternating is
164 * attempted.
166 * Return: negative errno code on a failure, -EINPROGRESS if the skb is
167 * buffered for later transmit or the NET_XMIT status returned by the
168 * lower routine if the packet has been passed down.
170 int batadv_send_skb_to_orig(struct sk_buff *skb,
171 struct batadv_orig_node *orig_node,
172 struct batadv_hard_iface *recv_if)
174 struct batadv_priv *bat_priv = orig_node->bat_priv;
175 struct batadv_neigh_node *neigh_node;
176 int ret;
178 /* batadv_find_router() increases neigh_nodes refcount if found. */
179 neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
180 if (!neigh_node) {
181 ret = -EINVAL;
182 goto free_skb;
185 /* Check if the skb is too large to send in one piece and fragment
186 * it if needed.
188 if (atomic_read(&bat_priv->fragmentation) &&
189 skb->len > neigh_node->if_incoming->net_dev->mtu) {
190 /* Fragment and send packet. */
191 ret = batadv_frag_send_packet(skb, orig_node, neigh_node);
192 /* skb was consumed */
193 skb = NULL;
195 goto put_neigh_node;
198 /* try to network code the packet, if it is received on an interface
199 * (i.e. being forwarded). If the packet originates from this node or if
200 * network coding fails, then send the packet as usual.
202 if (recv_if && batadv_nc_skb_forward(skb, neigh_node))
203 ret = -EINPROGRESS;
204 else
205 ret = batadv_send_unicast_skb(skb, neigh_node);
207 /* skb was consumed */
208 skb = NULL;
210 put_neigh_node:
211 batadv_neigh_node_put(neigh_node);
212 free_skb:
213 kfree_skb(skb);
215 return ret;
219 * batadv_send_skb_push_fill_unicast - extend the buffer and initialize the
220 * common fields for unicast packets
221 * @skb: the skb carrying the unicast header to initialize
222 * @hdr_size: amount of bytes to push at the beginning of the skb
223 * @orig_node: the destination node
225 * Return: false if the buffer extension was not possible or true otherwise.
227 static bool
228 batadv_send_skb_push_fill_unicast(struct sk_buff *skb, int hdr_size,
229 struct batadv_orig_node *orig_node)
231 struct batadv_unicast_packet *unicast_packet;
232 u8 ttvn = (u8)atomic_read(&orig_node->last_ttvn);
234 if (batadv_skb_head_push(skb, hdr_size) < 0)
235 return false;
237 unicast_packet = (struct batadv_unicast_packet *)skb->data;
238 unicast_packet->version = BATADV_COMPAT_VERSION;
239 /* batman packet type: unicast */
240 unicast_packet->packet_type = BATADV_UNICAST;
241 /* set unicast ttl */
242 unicast_packet->ttl = BATADV_TTL;
243 /* copy the destination for faster routing */
244 ether_addr_copy(unicast_packet->dest, orig_node->orig);
245 /* set the destination tt version number */
246 unicast_packet->ttvn = ttvn;
248 return true;
252 * batadv_send_skb_prepare_unicast - encapsulate an skb with a unicast header
253 * @skb: the skb containing the payload to encapsulate
254 * @orig_node: the destination node
256 * Return: false if the payload could not be encapsulated or true otherwise.
258 static bool batadv_send_skb_prepare_unicast(struct sk_buff *skb,
259 struct batadv_orig_node *orig_node)
261 size_t uni_size = sizeof(struct batadv_unicast_packet);
263 return batadv_send_skb_push_fill_unicast(skb, uni_size, orig_node);
267 * batadv_send_skb_prepare_unicast_4addr - encapsulate an skb with a
268 * unicast 4addr header
269 * @bat_priv: the bat priv with all the soft interface information
270 * @skb: the skb containing the payload to encapsulate
271 * @orig: the destination node
272 * @packet_subtype: the unicast 4addr packet subtype to use
274 * Return: false if the payload could not be encapsulated or true otherwise.
276 bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv,
277 struct sk_buff *skb,
278 struct batadv_orig_node *orig,
279 int packet_subtype)
281 struct batadv_hard_iface *primary_if;
282 struct batadv_unicast_4addr_packet *uc_4addr_packet;
283 bool ret = false;
285 primary_if = batadv_primary_if_get_selected(bat_priv);
286 if (!primary_if)
287 goto out;
289 /* Pull the header space and fill the unicast_packet substructure.
290 * We can do that because the first member of the uc_4addr_packet
291 * is of type struct unicast_packet
293 if (!batadv_send_skb_push_fill_unicast(skb, sizeof(*uc_4addr_packet),
294 orig))
295 goto out;
297 uc_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
298 uc_4addr_packet->u.packet_type = BATADV_UNICAST_4ADDR;
299 ether_addr_copy(uc_4addr_packet->src, primary_if->net_dev->dev_addr);
300 uc_4addr_packet->subtype = packet_subtype;
301 uc_4addr_packet->reserved = 0;
303 ret = true;
304 out:
305 if (primary_if)
306 batadv_hardif_put(primary_if);
307 return ret;
311 * batadv_send_skb_unicast - encapsulate and send an skb via unicast
312 * @bat_priv: the bat priv with all the soft interface information
313 * @skb: payload to send
314 * @packet_type: the batman unicast packet type to use
315 * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
316 * 4addr packets)
317 * @orig_node: the originator to send the packet to
318 * @vid: the vid to be used to search the translation table
320 * Wrap the given skb into a batman-adv unicast or unicast-4addr header
321 * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
322 * as packet_type. Then send this frame to the given orig_node.
324 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
326 int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
327 struct sk_buff *skb, int packet_type,
328 int packet_subtype,
329 struct batadv_orig_node *orig_node,
330 unsigned short vid)
332 struct batadv_unicast_packet *unicast_packet;
333 struct ethhdr *ethhdr;
334 int ret = NET_XMIT_DROP;
336 if (!orig_node)
337 goto out;
339 switch (packet_type) {
340 case BATADV_UNICAST:
341 if (!batadv_send_skb_prepare_unicast(skb, orig_node))
342 goto out;
343 break;
344 case BATADV_UNICAST_4ADDR:
345 if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
346 orig_node,
347 packet_subtype))
348 goto out;
349 break;
350 default:
351 /* this function supports UNICAST and UNICAST_4ADDR only. It
352 * should never be invoked with any other packet type
354 goto out;
357 /* skb->data might have been reallocated by
358 * batadv_send_skb_prepare_unicast{,_4addr}()
360 ethhdr = eth_hdr(skb);
361 unicast_packet = (struct batadv_unicast_packet *)skb->data;
363 /* inform the destination node that we are still missing a correct route
364 * for this client. The destination will receive this packet and will
365 * try to reroute it because the ttvn contained in the header is less
366 * than the current one
368 if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
369 unicast_packet->ttvn = unicast_packet->ttvn - 1;
371 ret = batadv_send_skb_to_orig(skb, orig_node, NULL);
372 /* skb was consumed */
373 skb = NULL;
375 out:
376 kfree_skb(skb);
377 return ret;
381 * batadv_send_skb_via_tt_generic - send an skb via TT lookup
382 * @bat_priv: the bat priv with all the soft interface information
383 * @skb: payload to send
384 * @packet_type: the batman unicast packet type to use
385 * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
386 * 4addr packets)
387 * @dst_hint: can be used to override the destination contained in the skb
388 * @vid: the vid to be used to search the translation table
390 * Look up the recipient node for the destination address in the ethernet
391 * header via the translation table. Wrap the given skb into a batman-adv
392 * unicast or unicast-4addr header depending on whether BATADV_UNICAST or
393 * BATADV_UNICAST_4ADDR was supplied as packet_type. Then send this frame
394 * to the according destination node.
396 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
398 int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
399 struct sk_buff *skb, int packet_type,
400 int packet_subtype, u8 *dst_hint,
401 unsigned short vid)
403 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
404 struct batadv_orig_node *orig_node;
405 u8 *src, *dst;
406 int ret;
408 src = ethhdr->h_source;
409 dst = ethhdr->h_dest;
411 /* if we got an hint! let's send the packet to this client (if any) */
412 if (dst_hint) {
413 src = NULL;
414 dst = dst_hint;
416 orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
418 ret = batadv_send_skb_unicast(bat_priv, skb, packet_type,
419 packet_subtype, orig_node, vid);
421 if (orig_node)
422 batadv_orig_node_put(orig_node);
424 return ret;
428 * batadv_send_skb_via_gw - send an skb via gateway lookup
429 * @bat_priv: the bat priv with all the soft interface information
430 * @skb: payload to send
431 * @vid: the vid to be used to search the translation table
433 * Look up the currently selected gateway. Wrap the given skb into a batman-adv
434 * unicast header and send this frame to this gateway node.
436 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
438 int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
439 unsigned short vid)
441 struct batadv_orig_node *orig_node;
442 int ret;
444 orig_node = batadv_gw_get_selected_orig(bat_priv);
445 ret = batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST_4ADDR,
446 BATADV_P_DATA, orig_node, vid);
448 if (orig_node)
449 batadv_orig_node_put(orig_node);
451 return ret;
455 * batadv_forw_packet_free - free a forwarding packet
456 * @forw_packet: The packet to free
457 * @dropped: whether the packet is freed because is is dropped
459 * This frees a forwarding packet and releases any resources it might
460 * have claimed.
462 void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet,
463 bool dropped)
465 if (dropped)
466 kfree_skb(forw_packet->skb);
467 else
468 consume_skb(forw_packet->skb);
470 if (forw_packet->if_incoming)
471 batadv_hardif_put(forw_packet->if_incoming);
472 if (forw_packet->if_outgoing)
473 batadv_hardif_put(forw_packet->if_outgoing);
474 if (forw_packet->queue_left)
475 atomic_inc(forw_packet->queue_left);
476 kfree(forw_packet);
480 * batadv_forw_packet_alloc - allocate a forwarding packet
481 * @if_incoming: The (optional) if_incoming to be grabbed
482 * @if_outgoing: The (optional) if_outgoing to be grabbed
483 * @queue_left: The (optional) queue counter to decrease
484 * @bat_priv: The bat_priv for the mesh of this forw_packet
485 * @skb: The raw packet this forwarding packet shall contain
487 * Allocates a forwarding packet and tries to get a reference to the
488 * (optional) if_incoming, if_outgoing and queue_left. If queue_left
489 * is NULL then bat_priv is optional, too.
491 * Return: An allocated forwarding packet on success, NULL otherwise.
493 struct batadv_forw_packet *
494 batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
495 struct batadv_hard_iface *if_outgoing,
496 atomic_t *queue_left,
497 struct batadv_priv *bat_priv,
498 struct sk_buff *skb)
500 struct batadv_forw_packet *forw_packet;
501 const char *qname;
503 if (queue_left && !batadv_atomic_dec_not_zero(queue_left)) {
504 qname = "unknown";
506 if (queue_left == &bat_priv->bcast_queue_left)
507 qname = "bcast";
509 if (queue_left == &bat_priv->batman_queue_left)
510 qname = "batman";
512 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
513 "%s queue is full\n", qname);
515 return NULL;
518 forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
519 if (!forw_packet)
520 goto err;
522 if (if_incoming)
523 kref_get(&if_incoming->refcount);
525 if (if_outgoing)
526 kref_get(&if_outgoing->refcount);
528 INIT_HLIST_NODE(&forw_packet->list);
529 INIT_HLIST_NODE(&forw_packet->cleanup_list);
530 forw_packet->skb = skb;
531 forw_packet->queue_left = queue_left;
532 forw_packet->if_incoming = if_incoming;
533 forw_packet->if_outgoing = if_outgoing;
534 forw_packet->num_packets = 0;
536 return forw_packet;
538 err:
539 if (queue_left)
540 atomic_inc(queue_left);
542 return NULL;
546 * batadv_forw_packet_was_stolen - check whether someone stole this packet
547 * @forw_packet: the forwarding packet to check
549 * This function checks whether the given forwarding packet was claimed by
550 * someone else for free().
552 * Return: True if someone stole it, false otherwise.
554 static bool
555 batadv_forw_packet_was_stolen(struct batadv_forw_packet *forw_packet)
557 return !hlist_unhashed(&forw_packet->cleanup_list);
561 * batadv_forw_packet_steal - claim a forw_packet for free()
562 * @forw_packet: the forwarding packet to steal
563 * @lock: a key to the store to steal from (e.g. forw_{bat,bcast}_list_lock)
565 * This function tries to steal a specific forw_packet from global
566 * visibility for the purpose of getting it for free(). That means
567 * the caller is *not* allowed to requeue it afterwards.
569 * Return: True if stealing was successful. False if someone else stole it
570 * before us.
572 bool batadv_forw_packet_steal(struct batadv_forw_packet *forw_packet,
573 spinlock_t *lock)
575 /* did purging routine steal it earlier? */
576 spin_lock_bh(lock);
577 if (batadv_forw_packet_was_stolen(forw_packet)) {
578 spin_unlock_bh(lock);
579 return false;
582 hlist_del_init(&forw_packet->list);
584 /* Just to spot misuse of this function */
585 hlist_add_fake(&forw_packet->cleanup_list);
587 spin_unlock_bh(lock);
588 return true;
592 * batadv_forw_packet_list_steal - claim a list of forward packets for free()
593 * @forw_list: the to be stolen forward packets
594 * @cleanup_list: a backup pointer, to be able to dispose the packet later
595 * @hard_iface: the interface to steal forward packets from
597 * This function claims responsibility to free any forw_packet queued on the
598 * given hard_iface. If hard_iface is NULL forwarding packets on all hard
599 * interfaces will be claimed.
601 * The packets are being moved from the forw_list to the cleanup_list and
602 * by that allows already running threads to notice the claiming.
604 static void
605 batadv_forw_packet_list_steal(struct hlist_head *forw_list,
606 struct hlist_head *cleanup_list,
607 const struct batadv_hard_iface *hard_iface)
609 struct batadv_forw_packet *forw_packet;
610 struct hlist_node *safe_tmp_node;
612 hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
613 forw_list, list) {
614 /* if purge_outstanding_packets() was called with an argument
615 * we delete only packets belonging to the given interface
617 if (hard_iface &&
618 (forw_packet->if_incoming != hard_iface) &&
619 (forw_packet->if_outgoing != hard_iface))
620 continue;
622 hlist_del(&forw_packet->list);
623 hlist_add_head(&forw_packet->cleanup_list, cleanup_list);
628 * batadv_forw_packet_list_free - free a list of forward packets
629 * @head: a list of to be freed forw_packets
631 * This function cancels the scheduling of any packet in the provided list,
632 * waits for any possibly running packet forwarding thread to finish and
633 * finally, safely frees this forward packet.
635 * This function might sleep.
637 static void batadv_forw_packet_list_free(struct hlist_head *head)
639 struct batadv_forw_packet *forw_packet;
640 struct hlist_node *safe_tmp_node;
642 hlist_for_each_entry_safe(forw_packet, safe_tmp_node, head,
643 cleanup_list) {
644 cancel_delayed_work_sync(&forw_packet->delayed_work);
646 hlist_del(&forw_packet->cleanup_list);
647 batadv_forw_packet_free(forw_packet, true);
652 * batadv_forw_packet_queue - try to queue a forwarding packet
653 * @forw_packet: the forwarding packet to queue
654 * @lock: a key to the store (e.g. forw_{bat,bcast}_list_lock)
655 * @head: the shelve to queue it on (e.g. forw_{bat,bcast}_list)
656 * @send_time: timestamp (jiffies) when the packet is to be sent
658 * This function tries to (re)queue a forwarding packet. Requeuing
659 * is prevented if the according interface is shutting down
660 * (e.g. if batadv_forw_packet_list_steal() was called for this
661 * packet earlier).
663 * Calling batadv_forw_packet_queue() after a call to
664 * batadv_forw_packet_steal() is forbidden!
666 * Caller needs to ensure that forw_packet->delayed_work was initialized.
668 static void batadv_forw_packet_queue(struct batadv_forw_packet *forw_packet,
669 spinlock_t *lock, struct hlist_head *head,
670 unsigned long send_time)
672 spin_lock_bh(lock);
674 /* did purging routine steal it from us? */
675 if (batadv_forw_packet_was_stolen(forw_packet)) {
676 /* If you got it for free() without trouble, then
677 * don't get back into the queue after stealing...
679 WARN_ONCE(hlist_fake(&forw_packet->cleanup_list),
680 "Requeuing after batadv_forw_packet_steal() not allowed!\n");
682 spin_unlock_bh(lock);
683 return;
686 hlist_del_init(&forw_packet->list);
687 hlist_add_head(&forw_packet->list, head);
689 queue_delayed_work(batadv_event_workqueue,
690 &forw_packet->delayed_work,
691 send_time - jiffies);
692 spin_unlock_bh(lock);
696 * batadv_forw_packet_bcast_queue - try to queue a broadcast packet
697 * @bat_priv: the bat priv with all the soft interface information
698 * @forw_packet: the forwarding packet to queue
699 * @send_time: timestamp (jiffies) when the packet is to be sent
701 * This function tries to (re)queue a broadcast packet.
703 * Caller needs to ensure that forw_packet->delayed_work was initialized.
705 static void
706 batadv_forw_packet_bcast_queue(struct batadv_priv *bat_priv,
707 struct batadv_forw_packet *forw_packet,
708 unsigned long send_time)
710 batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bcast_list_lock,
711 &bat_priv->forw_bcast_list, send_time);
715 * batadv_forw_packet_ogmv1_queue - try to queue an OGMv1 packet
716 * @bat_priv: the bat priv with all the soft interface information
717 * @forw_packet: the forwarding packet to queue
718 * @send_time: timestamp (jiffies) when the packet is to be sent
720 * This function tries to (re)queue an OGMv1 packet.
722 * Caller needs to ensure that forw_packet->delayed_work was initialized.
724 void batadv_forw_packet_ogmv1_queue(struct batadv_priv *bat_priv,
725 struct batadv_forw_packet *forw_packet,
726 unsigned long send_time)
728 batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bat_list_lock,
729 &bat_priv->forw_bat_list, send_time);
733 * batadv_add_bcast_packet_to_list - queue broadcast packet for multiple sends
734 * @bat_priv: the bat priv with all the soft interface information
735 * @skb: broadcast packet to add
736 * @delay: number of jiffies to wait before sending
737 * @own_packet: true if it is a self-generated broadcast packet
739 * add a broadcast packet to the queue and setup timers. broadcast packets
740 * are sent multiple times to increase probability for being received.
742 * The skb is not consumed, so the caller should make sure that the
743 * skb is freed.
745 * Return: NETDEV_TX_OK on success and NETDEV_TX_BUSY on errors.
747 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
748 const struct sk_buff *skb,
749 unsigned long delay,
750 bool own_packet)
752 struct batadv_hard_iface *primary_if;
753 struct batadv_forw_packet *forw_packet;
754 struct batadv_bcast_packet *bcast_packet;
755 struct sk_buff *newskb;
757 primary_if = batadv_primary_if_get_selected(bat_priv);
758 if (!primary_if)
759 goto err;
761 newskb = skb_copy(skb, GFP_ATOMIC);
762 if (!newskb) {
763 batadv_hardif_put(primary_if);
764 goto err;
767 forw_packet = batadv_forw_packet_alloc(primary_if, NULL,
768 &bat_priv->bcast_queue_left,
769 bat_priv, newskb);
770 batadv_hardif_put(primary_if);
771 if (!forw_packet)
772 goto err_packet_free;
774 /* as we have a copy now, it is safe to decrease the TTL */
775 bcast_packet = (struct batadv_bcast_packet *)newskb->data;
776 bcast_packet->ttl--;
778 forw_packet->own = own_packet;
780 INIT_DELAYED_WORK(&forw_packet->delayed_work,
781 batadv_send_outstanding_bcast_packet);
783 batadv_forw_packet_bcast_queue(bat_priv, forw_packet, jiffies + delay);
784 return NETDEV_TX_OK;
786 err_packet_free:
787 kfree_skb(newskb);
788 err:
789 return NETDEV_TX_BUSY;
793 * batadv_forw_packet_bcasts_left - check if a retransmission is necessary
794 * @forw_packet: the forwarding packet to check
795 * @hard_iface: the interface to check on
797 * Checks whether a given packet has any (re)transmissions left on the provided
798 * interface.
800 * hard_iface may be NULL: In that case the number of transmissions this skb had
801 * so far is compared with the maximum amount of retransmissions independent of
802 * any interface instead.
804 * Return: True if (re)transmissions are left, false otherwise.
806 static bool
807 batadv_forw_packet_bcasts_left(struct batadv_forw_packet *forw_packet,
808 struct batadv_hard_iface *hard_iface)
810 unsigned int max;
812 if (hard_iface)
813 max = hard_iface->num_bcasts;
814 else
815 max = BATADV_NUM_BCASTS_MAX;
817 return BATADV_SKB_CB(forw_packet->skb)->num_bcasts < max;
821 * batadv_forw_packet_bcasts_inc - increment retransmission counter of a packet
822 * @forw_packet: the packet to increase the counter for
824 static void
825 batadv_forw_packet_bcasts_inc(struct batadv_forw_packet *forw_packet)
827 BATADV_SKB_CB(forw_packet->skb)->num_bcasts++;
831 * batadv_forw_packet_is_rebroadcast - check packet for previous transmissions
832 * @forw_packet: the packet to check
834 * Return: True if this packet was transmitted before, false otherwise.
836 bool batadv_forw_packet_is_rebroadcast(struct batadv_forw_packet *forw_packet)
838 return BATADV_SKB_CB(forw_packet->skb)->num_bcasts > 0;
841 static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
843 struct batadv_hard_iface *hard_iface;
844 struct batadv_hardif_neigh_node *neigh_node;
845 struct delayed_work *delayed_work;
846 struct batadv_forw_packet *forw_packet;
847 struct batadv_bcast_packet *bcast_packet;
848 struct sk_buff *skb1;
849 struct net_device *soft_iface;
850 struct batadv_priv *bat_priv;
851 unsigned long send_time = jiffies + msecs_to_jiffies(5);
852 bool dropped = false;
853 u8 *neigh_addr;
854 u8 *orig_neigh;
855 int ret = 0;
857 delayed_work = to_delayed_work(work);
858 forw_packet = container_of(delayed_work, struct batadv_forw_packet,
859 delayed_work);
860 soft_iface = forw_packet->if_incoming->soft_iface;
861 bat_priv = netdev_priv(soft_iface);
863 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
864 dropped = true;
865 goto out;
868 if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) {
869 dropped = true;
870 goto out;
873 bcast_packet = (struct batadv_bcast_packet *)forw_packet->skb->data;
875 /* rebroadcast packet */
876 rcu_read_lock();
877 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
878 if (hard_iface->soft_iface != soft_iface)
879 continue;
881 if (!batadv_forw_packet_bcasts_left(forw_packet, hard_iface))
882 continue;
884 if (forw_packet->own) {
885 neigh_node = NULL;
886 } else {
887 neigh_addr = eth_hdr(forw_packet->skb)->h_source;
888 neigh_node = batadv_hardif_neigh_get(hard_iface,
889 neigh_addr);
892 orig_neigh = neigh_node ? neigh_node->orig : NULL;
894 ret = batadv_hardif_no_broadcast(hard_iface, bcast_packet->orig,
895 orig_neigh);
897 if (ret) {
898 char *type;
900 switch (ret) {
901 case BATADV_HARDIF_BCAST_NORECIPIENT:
902 type = "no neighbor";
903 break;
904 case BATADV_HARDIF_BCAST_DUPFWD:
905 type = "single neighbor is source";
906 break;
907 case BATADV_HARDIF_BCAST_DUPORIG:
908 type = "single neighbor is originator";
909 break;
910 default:
911 type = "unknown";
914 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "BCAST packet from orig %pM on %s surpressed: %s\n",
915 bcast_packet->orig,
916 hard_iface->net_dev->name, type);
918 if (neigh_node)
919 batadv_hardif_neigh_put(neigh_node);
921 continue;
924 if (neigh_node)
925 batadv_hardif_neigh_put(neigh_node);
927 if (!kref_get_unless_zero(&hard_iface->refcount))
928 continue;
930 /* send a copy of the saved skb */
931 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
932 if (skb1)
933 batadv_send_broadcast_skb(skb1, hard_iface);
935 batadv_hardif_put(hard_iface);
937 rcu_read_unlock();
939 batadv_forw_packet_bcasts_inc(forw_packet);
941 /* if we still have some more bcasts to send */
942 if (batadv_forw_packet_bcasts_left(forw_packet, NULL)) {
943 batadv_forw_packet_bcast_queue(bat_priv, forw_packet,
944 send_time);
945 return;
948 out:
949 /* do we get something for free()? */
950 if (batadv_forw_packet_steal(forw_packet,
951 &bat_priv->forw_bcast_list_lock))
952 batadv_forw_packet_free(forw_packet, dropped);
956 * batadv_purge_outstanding_packets - stop/purge scheduled bcast/OGMv1 packets
957 * @bat_priv: the bat priv with all the soft interface information
958 * @hard_iface: the hard interface to cancel and purge bcast/ogm packets on
960 * This method cancels and purges any broadcast and OGMv1 packet on the given
961 * hard_iface. If hard_iface is NULL, broadcast and OGMv1 packets on all hard
962 * interfaces will be canceled and purged.
964 * This function might sleep.
966 void
967 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
968 const struct batadv_hard_iface *hard_iface)
970 struct hlist_head head = HLIST_HEAD_INIT;
972 if (hard_iface)
973 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
974 "%s(): %s\n",
975 __func__, hard_iface->net_dev->name);
976 else
977 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
978 "%s()\n", __func__);
980 /* claim bcast list for free() */
981 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
982 batadv_forw_packet_list_steal(&bat_priv->forw_bcast_list, &head,
983 hard_iface);
984 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
986 /* claim batman packet list for free() */
987 spin_lock_bh(&bat_priv->forw_bat_list_lock);
988 batadv_forw_packet_list_steal(&bat_priv->forw_bat_list, &head,
989 hard_iface);
990 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
992 /* then cancel or wait for packet workers to finish and free */
993 batadv_forw_packet_list_free(&head);