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/errno.h>
24 #include <linux/etherdevice.h>
27 #include <linux/if_ether.h>
28 #include <linux/jiffies.h>
29 #include <linux/kernel.h>
30 #include <linux/kref.h>
31 #include <linux/list.h>
32 #include <linux/netdevice.h>
33 #include <linux/printk.h>
34 #include <linux/rculist.h>
35 #include <linux/rcupdate.h>
36 #include <linux/skbuff.h>
37 #include <linux/slab.h>
38 #include <linux/spinlock.h>
39 #include <linux/stddef.h>
40 #include <linux/workqueue.h>
42 #include "distributed-arp-table.h"
43 #include "fragmentation.h"
44 #include "gateway_client.h"
45 #include "hard-interface.h"
47 #include "network-coding.h"
48 #include "originator.h"
50 #include "soft-interface.h"
51 #include "translation-table.h"
53 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
56 * batadv_send_skb_packet - send an already prepared packet
57 * @skb: the packet to send
58 * @hard_iface: the interface to use to send the broadcast packet
59 * @dst_addr: the payload destination
61 * Send out an already prepared packet to the given neighbor or broadcast it
62 * using the specified interface. Either hard_iface or neigh_node must be not
64 * If neigh_node is NULL, then the packet is broadcasted using hard_iface,
65 * otherwise it is sent as unicast to the given neighbor.
67 * Return: NET_TX_DROP in case of error or the result of dev_queue_xmit(skb)
70 int batadv_send_skb_packet(struct sk_buff *skb,
71 struct batadv_hard_iface *hard_iface,
74 struct batadv_priv *bat_priv;
75 struct ethhdr *ethhdr;
78 bat_priv = netdev_priv(hard_iface->soft_iface);
80 if (hard_iface->if_status != BATADV_IF_ACTIVE)
83 if (unlikely(!hard_iface->net_dev))
86 if (!(hard_iface->net_dev->flags & IFF_UP)) {
87 pr_warn("Interface %s is not up - can't send packet via that interface!\n",
88 hard_iface->net_dev->name);
92 /* push to the ethernet header. */
93 if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
96 skb_reset_mac_header(skb);
98 ethhdr = eth_hdr(skb);
99 ether_addr_copy(ethhdr->h_source, hard_iface->net_dev->dev_addr);
100 ether_addr_copy(ethhdr->h_dest, dst_addr);
101 ethhdr->h_proto = htons(ETH_P_BATMAN);
103 skb_set_network_header(skb, ETH_HLEN);
104 skb->protocol = htons(ETH_P_BATMAN);
106 skb->dev = hard_iface->net_dev;
108 /* Save a clone of the skb to use when decoding coded packets */
109 batadv_nc_skb_store_for_decoding(bat_priv, skb);
111 /* dev_queue_xmit() returns a negative result on error. However on
112 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
113 * (which is > 0). This will not be treated as an error.
115 * a negative value cannot be returned because it could be interepreted
116 * as not consumed skb by callers of batadv_send_skb_to_orig.
118 ret = dev_queue_xmit(skb);
125 return NET_XMIT_DROP;
128 int batadv_send_broadcast_skb(struct sk_buff *skb,
129 struct batadv_hard_iface *hard_iface)
131 return batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
134 int batadv_send_unicast_skb(struct sk_buff *skb,
135 struct batadv_neigh_node *neigh)
137 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
138 struct batadv_hardif_neigh_node *hardif_neigh;
142 ret = batadv_send_skb_packet(skb, neigh->if_incoming, neigh->addr);
144 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
145 hardif_neigh = batadv_hardif_neigh_get(neigh->if_incoming, neigh->addr);
147 if ((hardif_neigh) && (ret != NET_XMIT_DROP))
148 hardif_neigh->bat_v.last_unicast_tx = jiffies;
151 batadv_hardif_neigh_put(hardif_neigh);
158 * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
159 * @skb: Packet to be transmitted.
160 * @orig_node: Final destination of the packet.
161 * @recv_if: Interface used when receiving the packet (can be NULL).
163 * Looks up the best next-hop towards the passed originator and passes the
164 * skb on for preparation of MAC header. If the packet originated from this
165 * host, NULL can be passed as recv_if and no interface alternating is
168 * Return: -1 on failure (and the skb is not consumed), -EINPROGRESS if the
169 * skb is buffered for later transmit or the NET_XMIT status returned by the
170 * lower routine if the packet has been passed down.
172 * If the returning value is not -1 the skb has been consumed.
174 int batadv_send_skb_to_orig(struct sk_buff *skb,
175 struct batadv_orig_node *orig_node,
176 struct batadv_hard_iface *recv_if)
178 struct batadv_priv *bat_priv = orig_node->bat_priv;
179 struct batadv_neigh_node *neigh_node;
182 /* batadv_find_router() increases neigh_nodes refcount if found. */
183 neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
187 /* Check if the skb is too large to send in one piece and fragment
190 if (atomic_read(&bat_priv->fragmentation) &&
191 skb->len > neigh_node->if_incoming->net_dev->mtu) {
192 /* Fragment and send packet. */
193 ret = batadv_frag_send_packet(skb, orig_node, 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))
205 ret = batadv_send_unicast_skb(skb, neigh_node);
209 batadv_neigh_node_put(neigh_node);
215 * batadv_send_skb_push_fill_unicast - extend the buffer and initialize the
216 * common fields for unicast packets
217 * @skb: the skb carrying the unicast header to initialize
218 * @hdr_size: amount of bytes to push at the beginning of the skb
219 * @orig_node: the destination node
221 * Return: false if the buffer extension was not possible or true otherwise.
224 batadv_send_skb_push_fill_unicast(struct sk_buff *skb, int hdr_size,
225 struct batadv_orig_node *orig_node)
227 struct batadv_unicast_packet *unicast_packet;
228 u8 ttvn = (u8)atomic_read(&orig_node->last_ttvn);
230 if (batadv_skb_head_push(skb, hdr_size) < 0)
233 unicast_packet = (struct batadv_unicast_packet *)skb->data;
234 unicast_packet->version = BATADV_COMPAT_VERSION;
235 /* batman packet type: unicast */
236 unicast_packet->packet_type = BATADV_UNICAST;
237 /* set unicast ttl */
238 unicast_packet->ttl = BATADV_TTL;
239 /* copy the destination for faster routing */
240 ether_addr_copy(unicast_packet->dest, orig_node->orig);
241 /* set the destination tt version number */
242 unicast_packet->ttvn = ttvn;
248 * batadv_send_skb_prepare_unicast - encapsulate an skb with a unicast header
249 * @skb: the skb containing the payload to encapsulate
250 * @orig_node: the destination node
252 * Return: false if the payload could not be encapsulated or true otherwise.
254 static bool batadv_send_skb_prepare_unicast(struct sk_buff *skb,
255 struct batadv_orig_node *orig_node)
257 size_t uni_size = sizeof(struct batadv_unicast_packet);
259 return batadv_send_skb_push_fill_unicast(skb, uni_size, orig_node);
263 * batadv_send_skb_prepare_unicast_4addr - encapsulate an skb with a
264 * unicast 4addr header
265 * @bat_priv: the bat priv with all the soft interface information
266 * @skb: the skb containing the payload to encapsulate
267 * @orig: the destination node
268 * @packet_subtype: the unicast 4addr packet subtype to use
270 * Return: false if the payload could not be encapsulated or true otherwise.
272 bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv,
274 struct batadv_orig_node *orig,
277 struct batadv_hard_iface *primary_if;
278 struct batadv_unicast_4addr_packet *uc_4addr_packet;
281 primary_if = batadv_primary_if_get_selected(bat_priv);
285 /* Pull the header space and fill the unicast_packet substructure.
286 * We can do that because the first member of the uc_4addr_packet
287 * is of type struct unicast_packet
289 if (!batadv_send_skb_push_fill_unicast(skb, sizeof(*uc_4addr_packet),
293 uc_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
294 uc_4addr_packet->u.packet_type = BATADV_UNICAST_4ADDR;
295 ether_addr_copy(uc_4addr_packet->src, primary_if->net_dev->dev_addr);
296 uc_4addr_packet->subtype = packet_subtype;
297 uc_4addr_packet->reserved = 0;
302 batadv_hardif_put(primary_if);
307 * batadv_send_skb_unicast - encapsulate and send an skb via unicast
308 * @bat_priv: the bat priv with all the soft interface information
309 * @skb: payload to send
310 * @packet_type: the batman unicast packet type to use
311 * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
313 * @orig_node: the originator to send the packet to
314 * @vid: the vid to be used to search the translation table
316 * Wrap the given skb into a batman-adv unicast or unicast-4addr header
317 * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
318 * as packet_type. Then send this frame to the given orig_node and release a
319 * reference to this orig_node.
321 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
323 int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
324 struct sk_buff *skb, int packet_type,
326 struct batadv_orig_node *orig_node,
329 struct batadv_unicast_packet *unicast_packet;
330 struct ethhdr *ethhdr;
331 int res, ret = NET_XMIT_DROP;
336 switch (packet_type) {
338 if (!batadv_send_skb_prepare_unicast(skb, orig_node))
341 case BATADV_UNICAST_4ADDR:
342 if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
348 /* this function supports UNICAST and UNICAST_4ADDR only. It
349 * should never be invoked with any other packet type
354 /* skb->data might have been reallocated by
355 * batadv_send_skb_prepare_unicast{,_4addr}()
357 ethhdr = eth_hdr(skb);
358 unicast_packet = (struct batadv_unicast_packet *)skb->data;
360 /* inform the destination node that we are still missing a correct route
361 * for this client. The destination will receive this packet and will
362 * try to reroute it because the ttvn contained in the header is less
363 * than the current one
365 if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
366 unicast_packet->ttvn = unicast_packet->ttvn - 1;
368 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
370 ret = NET_XMIT_SUCCESS;
374 batadv_orig_node_put(orig_node);
375 if (ret == NET_XMIT_DROP)
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
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,
403 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
404 struct batadv_orig_node *orig_node;
407 src = ethhdr->h_source;
408 dst = ethhdr->h_dest;
410 /* if we got an hint! let's send the packet to this client (if any) */
415 orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
417 return batadv_send_skb_unicast(bat_priv, skb, packet_type,
418 packet_subtype, orig_node, vid);
422 * batadv_send_skb_via_gw - send an skb via gateway lookup
423 * @bat_priv: the bat priv with all the soft interface information
424 * @skb: payload to send
425 * @vid: the vid to be used to search the translation table
427 * Look up the currently selected gateway. Wrap the given skb into a batman-adv
428 * unicast header and send this frame to this gateway node.
430 * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
432 int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
435 struct batadv_orig_node *orig_node;
437 orig_node = batadv_gw_get_selected_orig(bat_priv);
438 return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST_4ADDR,
439 BATADV_P_DATA, orig_node, vid);
442 void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
444 kfree_skb(forw_packet->skb);
445 if (forw_packet->if_incoming)
446 batadv_hardif_put(forw_packet->if_incoming);
447 if (forw_packet->if_outgoing)
448 batadv_hardif_put(forw_packet->if_outgoing);
453 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
454 struct batadv_forw_packet *forw_packet,
455 unsigned long send_time)
457 /* add new packet to packet list */
458 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
459 hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
460 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
462 /* start timer for this packet */
463 queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
468 * batadv_add_bcast_packet_to_list - queue broadcast packet for multiple sends
469 * @bat_priv: the bat priv with all the soft interface information
470 * @skb: broadcast packet to add
471 * @delay: number of jiffies to wait before sending
473 * add a broadcast packet to the queue and setup timers. broadcast packets
474 * are sent multiple times to increase probability for being received.
476 * The skb is not consumed, so the caller should make sure that the
479 * Return: NETDEV_TX_OK on success and NETDEV_TX_BUSY on errors.
481 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
482 const struct sk_buff *skb,
485 struct batadv_hard_iface *primary_if = NULL;
486 struct batadv_forw_packet *forw_packet;
487 struct batadv_bcast_packet *bcast_packet;
488 struct sk_buff *newskb;
490 if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
491 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
492 "bcast packet queue full\n");
496 primary_if = batadv_primary_if_get_selected(bat_priv);
500 forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
505 newskb = skb_copy(skb, GFP_ATOMIC);
509 /* as we have a copy now, it is safe to decrease the TTL */
510 bcast_packet = (struct batadv_bcast_packet *)newskb->data;
513 skb_reset_mac_header(newskb);
515 forw_packet->skb = newskb;
516 forw_packet->if_incoming = primary_if;
517 forw_packet->if_outgoing = NULL;
519 /* how often did we send the bcast packet ? */
520 forw_packet->num_packets = 0;
522 INIT_DELAYED_WORK(&forw_packet->delayed_work,
523 batadv_send_outstanding_bcast_packet);
525 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
531 atomic_inc(&bat_priv->bcast_queue_left);
534 batadv_hardif_put(primary_if);
535 return NETDEV_TX_BUSY;
538 static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
540 struct batadv_hard_iface *hard_iface;
541 struct delayed_work *delayed_work;
542 struct batadv_forw_packet *forw_packet;
543 struct sk_buff *skb1;
544 struct net_device *soft_iface;
545 struct batadv_priv *bat_priv;
547 delayed_work = to_delayed_work(work);
548 forw_packet = container_of(delayed_work, struct batadv_forw_packet,
550 soft_iface = forw_packet->if_incoming->soft_iface;
551 bat_priv = netdev_priv(soft_iface);
553 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
554 hlist_del(&forw_packet->list);
555 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
557 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
560 if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
563 /* rebroadcast packet */
565 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
566 if (hard_iface->soft_iface != soft_iface)
569 if (forw_packet->num_packets >= hard_iface->num_bcasts)
572 if (!kref_get_unless_zero(&hard_iface->refcount))
575 /* send a copy of the saved skb */
576 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
578 batadv_send_broadcast_skb(skb1, hard_iface);
580 batadv_hardif_put(hard_iface);
584 forw_packet->num_packets++;
586 /* if we still have some more bcasts to send */
587 if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
588 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
589 msecs_to_jiffies(5));
594 batadv_forw_packet_free(forw_packet);
595 atomic_inc(&bat_priv->bcast_queue_left);
599 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
600 const struct batadv_hard_iface *hard_iface)
602 struct batadv_forw_packet *forw_packet;
603 struct hlist_node *safe_tmp_node;
607 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
608 "purge_outstanding_packets(): %s\n",
609 hard_iface->net_dev->name);
611 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
612 "purge_outstanding_packets()\n");
614 /* free bcast list */
615 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
616 hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
617 &bat_priv->forw_bcast_list, list) {
618 /* if purge_outstanding_packets() was called with an argument
619 * we delete only packets belonging to the given interface
622 (forw_packet->if_incoming != hard_iface) &&
623 (forw_packet->if_outgoing != hard_iface))
626 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
628 /* batadv_send_outstanding_bcast_packet() will lock the list to
629 * delete the item from the list
631 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
632 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
635 hlist_del(&forw_packet->list);
636 if (!forw_packet->own)
637 atomic_inc(&bat_priv->bcast_queue_left);
639 batadv_forw_packet_free(forw_packet);
642 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
644 /* free batman packet list */
645 spin_lock_bh(&bat_priv->forw_bat_list_lock);
646 hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
647 &bat_priv->forw_bat_list, list) {
648 /* if purge_outstanding_packets() was called with an argument
649 * we delete only packets belonging to the given interface
652 (forw_packet->if_incoming != hard_iface) &&
653 (forw_packet->if_outgoing != hard_iface))
656 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
658 /* send_outstanding_bat_packet() will lock the list to
659 * delete the item from the list
661 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
662 spin_lock_bh(&bat_priv->forw_bat_list_lock);
665 hlist_del(&forw_packet->list);
666 if (!forw_packet->own)
667 atomic_inc(&bat_priv->batman_queue_left);
669 batadv_forw_packet_free(forw_packet);
672 spin_unlock_bh(&bat_priv->forw_bat_list_lock);