blob: 38b9aab83fc0eaf63e3713d278482524253d5c1a [file] [log] [blame]
Antonio Quartulli0da00352016-01-16 16:40:12 +08001/* Copyright (C) 2013-2016 B.A.T.M.A.N. contributors:
2 *
3 * Antonio Quartulli
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
16 */
17
18#include "bat_v_ogm.h"
19#include "main.h"
20
21#include <linux/atomic.h>
22#include <linux/byteorder/generic.h>
23#include <linux/errno.h>
24#include <linux/etherdevice.h>
25#include <linux/fs.h>
26#include <linux/if_ether.h>
27#include <linux/jiffies.h>
28#include <linux/kernel.h>
Sven Eckelmann27353442016-03-05 16:09:16 +010029#include <linux/kref.h>
Antonio Quartulli93231582016-01-16 16:40:13 +080030#include <linux/list.h>
Antonio Quartulli0da00352016-01-16 16:40:12 +080031#include <linux/netdevice.h>
32#include <linux/random.h>
33#include <linux/rculist.h>
34#include <linux/rcupdate.h>
35#include <linux/skbuff.h>
36#include <linux/slab.h>
37#include <linux/stddef.h>
38#include <linux/string.h>
39#include <linux/types.h>
40#include <linux/workqueue.h>
41
Sven Eckelmann01d350d2016-05-15 11:07:44 +020042#include "bat_algo.h"
Antonio Quartulli0da00352016-01-16 16:40:12 +080043#include "hard-interface.h"
Antonio Quartulli93231582016-01-16 16:40:13 +080044#include "hash.h"
Sven Eckelmannba412082016-05-15 23:48:31 +020045#include "log.h"
Antonio Quartulli93231582016-01-16 16:40:13 +080046#include "originator.h"
Antonio Quartulli0da00352016-01-16 16:40:12 +080047#include "packet.h"
48#include "routing.h"
49#include "send.h"
50#include "translation-table.h"
Markus Pargmann1f8dce42016-05-15 11:07:43 +020051#include "tvlv.h"
Antonio Quartulli0da00352016-01-16 16:40:12 +080052
53/**
Antonio Quartulli93231582016-01-16 16:40:13 +080054 * batadv_v_ogm_orig_get - retrieve and possibly create an originator node
55 * @bat_priv: the bat priv with all the soft interface information
56 * @addr: the address of the originator
57 *
58 * Return: the orig_node corresponding to the specified address. If such object
59 * does not exist it is allocated here. In case of allocation failure returns
60 * NULL.
61 */
62struct batadv_orig_node *batadv_v_ogm_orig_get(struct batadv_priv *bat_priv,
63 const u8 *addr)
64{
65 struct batadv_orig_node *orig_node;
66 int hash_added;
67
68 orig_node = batadv_orig_hash_find(bat_priv, addr);
69 if (orig_node)
70 return orig_node;
71
72 orig_node = batadv_orig_node_new(bat_priv, addr);
73 if (!orig_node)
74 return NULL;
75
Sven Eckelmann55db2d52016-07-15 17:39:21 +020076 kref_get(&orig_node->refcount);
Antonio Quartulli93231582016-01-16 16:40:13 +080077 hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
78 batadv_choose_orig, orig_node,
79 &orig_node->hash_entry);
80 if (hash_added != 0) {
Sven Eckelmann55db2d52016-07-15 17:39:21 +020081 /* remove refcnt for newly created orig_node and hash entry */
Antonio Quartulli93231582016-01-16 16:40:13 +080082 batadv_orig_node_put(orig_node);
83 batadv_orig_node_put(orig_node);
84 orig_node = NULL;
85 }
86
87 return orig_node;
88}
89
90/**
Antonio Quartulli0da00352016-01-16 16:40:12 +080091 * batadv_v_ogm_start_timer - restart the OGM sending timer
92 * @bat_priv: the bat priv with all the soft interface information
93 */
94static void batadv_v_ogm_start_timer(struct batadv_priv *bat_priv)
95{
96 unsigned long msecs;
97 /* this function may be invoked in different contexts (ogm rescheduling
98 * or hard_iface activation), but the work timer should not be reset
99 */
100 if (delayed_work_pending(&bat_priv->bat_v.ogm_wq))
101 return;
102
103 msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
104 msecs += prandom_u32() % (2 * BATADV_JITTER);
105 queue_delayed_work(batadv_event_workqueue, &bat_priv->bat_v.ogm_wq,
106 msecs_to_jiffies(msecs));
107}
108
109/**
110 * batadv_v_ogm_send_to_if - send a batman ogm using a given interface
111 * @skb: the OGM to send
112 * @hard_iface: the interface to use to send the OGM
113 */
114static void batadv_v_ogm_send_to_if(struct sk_buff *skb,
115 struct batadv_hard_iface *hard_iface)
116{
117 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
118
119 if (hard_iface->if_status != BATADV_IF_ACTIVE)
120 return;
121
122 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
123 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
124 skb->len + ETH_HLEN);
125
Antonio Quartulli95d39272016-01-16 16:40:15 +0800126 batadv_send_broadcast_skb(skb, hard_iface);
Antonio Quartulli0da00352016-01-16 16:40:12 +0800127}
128
129/**
130 * batadv_v_ogm_send - periodic worker broadcasting the own OGM
131 * @work: work queue item
132 */
133static void batadv_v_ogm_send(struct work_struct *work)
134{
135 struct batadv_hard_iface *hard_iface;
136 struct batadv_priv_bat_v *bat_v;
137 struct batadv_priv *bat_priv;
138 struct batadv_ogm2_packet *ogm_packet;
139 struct sk_buff *skb, *skb_tmp;
140 unsigned char *ogm_buff, *pkt_buff;
141 int ogm_buff_len;
142 u16 tvlv_len = 0;
Linus Lüssing3111bee2016-08-07 12:34:19 +0200143 int ret;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800144
145 bat_v = container_of(work, struct batadv_priv_bat_v, ogm_wq.work);
146 bat_priv = container_of(bat_v, struct batadv_priv, bat_v);
147
148 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
149 goto out;
150
151 ogm_buff = bat_priv->bat_v.ogm_buff;
152 ogm_buff_len = bat_priv->bat_v.ogm_buff_len;
153 /* tt changes have to be committed before the tvlv data is
154 * appended as it may alter the tt tvlv container
155 */
156 batadv_tt_local_commit_changes(bat_priv);
157 tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, &ogm_buff,
158 &ogm_buff_len,
159 BATADV_OGM2_HLEN);
160
161 bat_priv->bat_v.ogm_buff = ogm_buff;
162 bat_priv->bat_v.ogm_buff_len = ogm_buff_len;
163
164 skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + ogm_buff_len);
165 if (!skb)
166 goto reschedule;
167
168 skb_reserve(skb, ETH_HLEN);
169 pkt_buff = skb_put(skb, ogm_buff_len);
170 memcpy(pkt_buff, ogm_buff, ogm_buff_len);
171
172 ogm_packet = (struct batadv_ogm2_packet *)skb->data;
173 ogm_packet->seqno = htonl(atomic_read(&bat_priv->bat_v.ogm_seqno));
174 atomic_inc(&bat_priv->bat_v.ogm_seqno);
175 ogm_packet->tvlv_len = htons(tvlv_len);
176
177 /* broadcast on every interface */
178 rcu_read_lock();
179 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
180 if (hard_iface->soft_iface != bat_priv->soft_iface)
181 continue;
182
Sven Eckelmann27353442016-03-05 16:09:16 +0100183 if (!kref_get_unless_zero(&hard_iface->refcount))
184 continue;
185
Linus Lüssing3111bee2016-08-07 12:34:19 +0200186 ret = batadv_hardif_no_broadcast(hard_iface, NULL, NULL);
187 if (ret) {
188 char *type;
189
190 switch (ret) {
191 case BATADV_HARDIF_BCAST_NORECIPIENT:
192 type = "no neighbor";
193 break;
194 case BATADV_HARDIF_BCAST_DUPFWD:
195 type = "single neighbor is source";
196 break;
197 case BATADV_HARDIF_BCAST_DUPORIG:
198 type = "single neighbor is originator";
199 break;
200 default:
201 type = "unknown";
202 }
203
204 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "OGM2 from ourselve on %s surpressed: %s\n",
205 hard_iface->net_dev->name, type);
206
207 batadv_hardif_put(hard_iface);
208 continue;
209 }
210
Antonio Quartulli0da00352016-01-16 16:40:12 +0800211 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
212 "Sending own OGM2 packet (originator %pM, seqno %u, throughput %u, TTL %d) on interface %s [%pM]\n",
213 ogm_packet->orig, ntohl(ogm_packet->seqno),
214 ntohl(ogm_packet->throughput), ogm_packet->ttl,
215 hard_iface->net_dev->name,
216 hard_iface->net_dev->dev_addr);
217
218 /* this skb gets consumed by batadv_v_ogm_send_to_if() */
219 skb_tmp = skb_clone(skb, GFP_ATOMIC);
Sven Eckelmann27353442016-03-05 16:09:16 +0100220 if (!skb_tmp) {
221 batadv_hardif_put(hard_iface);
Antonio Quartulli0da00352016-01-16 16:40:12 +0800222 break;
Sven Eckelmann27353442016-03-05 16:09:16 +0100223 }
Antonio Quartulli0da00352016-01-16 16:40:12 +0800224
225 batadv_v_ogm_send_to_if(skb_tmp, hard_iface);
Sven Eckelmann27353442016-03-05 16:09:16 +0100226 batadv_hardif_put(hard_iface);
Antonio Quartulli0da00352016-01-16 16:40:12 +0800227 }
228 rcu_read_unlock();
229
230 consume_skb(skb);
231
232reschedule:
233 batadv_v_ogm_start_timer(bat_priv);
234out:
235 return;
236}
237
238/**
239 * batadv_v_ogm_iface_enable - prepare an interface for B.A.T.M.A.N. V
240 * @hard_iface: the interface to prepare
241 *
242 * Takes care of scheduling own OGM sending routine for this interface.
243 *
244 * Return: 0 on success or a negative error code otherwise
245 */
246int batadv_v_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
247{
248 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
249
250 batadv_v_ogm_start_timer(bat_priv);
251
252 return 0;
253}
254
255/**
256 * batadv_v_ogm_primary_iface_set - set a new primary interface
257 * @primary_iface: the new primary interface
258 */
259void batadv_v_ogm_primary_iface_set(struct batadv_hard_iface *primary_iface)
260{
261 struct batadv_priv *bat_priv = netdev_priv(primary_iface->soft_iface);
262 struct batadv_ogm2_packet *ogm_packet;
263
264 if (!bat_priv->bat_v.ogm_buff)
265 return;
266
267 ogm_packet = (struct batadv_ogm2_packet *)bat_priv->bat_v.ogm_buff;
268 ether_addr_copy(ogm_packet->orig, primary_iface->net_dev->dev_addr);
269}
270
271/**
Antonio Quartulli93231582016-01-16 16:40:13 +0800272 * batadv_v_forward_penalty - apply a penalty to the throughput metric forwarded
273 * with B.A.T.M.A.N. V OGMs
274 * @bat_priv: the bat priv with all the soft interface information
275 * @if_incoming: the interface where the OGM has been received
276 * @if_outgoing: the interface where the OGM has to be forwarded to
277 * @throughput: the current throughput
278 *
279 * Apply a penalty on the current throughput metric value based on the
280 * characteristic of the interface where the OGM has been received. The return
281 * value is computed as follows:
282 * - throughput * 50% if the incoming and outgoing interface are the
283 * same WiFi interface and the throughput is above
284 * 1MBit/s
285 * - throughput if the outgoing interface is the default
286 * interface (i.e. this OGM is processed for the
287 * internal table and not forwarded)
288 * - throughput * hop penalty otherwise
289 *
290 * Return: the penalised throughput metric.
291 */
292static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv,
293 struct batadv_hard_iface *if_incoming,
294 struct batadv_hard_iface *if_outgoing,
295 u32 throughput)
296{
297 int hop_penalty = atomic_read(&bat_priv->hop_penalty);
298 int hop_penalty_max = BATADV_TQ_MAX_VALUE;
299
300 /* Don't apply hop penalty in default originator table. */
301 if (if_outgoing == BATADV_IF_DEFAULT)
302 return throughput;
303
304 /* Forwarding on the same WiFi interface cuts the throughput in half
305 * due to the store & forward characteristics of WIFI.
306 * Very low throughput values are the exception.
307 */
308 if ((throughput > 10) &&
309 (if_incoming == if_outgoing) &&
Antonio Quartullic8334842015-11-10 18:50:51 +0100310 !(if_incoming->bat_v.flags & BATADV_FULL_DUPLEX))
Antonio Quartulli93231582016-01-16 16:40:13 +0800311 return throughput / 2;
312
313 /* hop penalty of 255 equals 100% */
314 return throughput * (hop_penalty_max - hop_penalty) / hop_penalty_max;
315}
316
317/**
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100318 * batadv_v_ogm_forward - check conditions and forward an OGM to the given
319 * outgoing interface
Antonio Quartulli93231582016-01-16 16:40:13 +0800320 * @bat_priv: the bat priv with all the soft interface information
321 * @ogm_received: previously received OGM to be forwarded
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100322 * @orig_node: the originator which has been updated
323 * @neigh_node: the neigh_node through with the OGM has been received
Antonio Quartulli93231582016-01-16 16:40:13 +0800324 * @if_incoming: the interface on which this OGM was received on
325 * @if_outgoing: the interface to which the OGM has to be forwarded to
326 *
327 * Forward an OGM to an interface after having altered the throughput metric and
328 * the TTL value contained in it. The original OGM isn't modified.
329 */
330static void batadv_v_ogm_forward(struct batadv_priv *bat_priv,
331 const struct batadv_ogm2_packet *ogm_received,
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100332 struct batadv_orig_node *orig_node,
333 struct batadv_neigh_node *neigh_node,
Antonio Quartulli93231582016-01-16 16:40:13 +0800334 struct batadv_hard_iface *if_incoming,
335 struct batadv_hard_iface *if_outgoing)
336{
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100337 struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
338 struct batadv_orig_ifinfo *orig_ifinfo = NULL;
339 struct batadv_neigh_node *router = NULL;
Antonio Quartulli93231582016-01-16 16:40:13 +0800340 struct batadv_ogm2_packet *ogm_forward;
341 unsigned char *skb_buff;
342 struct sk_buff *skb;
343 size_t packet_len;
344 u16 tvlv_len;
345
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100346 /* only forward for specific interfaces, not for the default one. */
347 if (if_outgoing == BATADV_IF_DEFAULT)
348 goto out;
349
350 orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
351 if (!orig_ifinfo)
352 goto out;
353
354 /* acquire possibly updated router */
355 router = batadv_orig_router_get(orig_node, if_outgoing);
356
357 /* strict rule: forward packets coming from the best next hop only */
358 if (neigh_node != router)
359 goto out;
360
361 /* don't forward the same seqno twice on one interface */
362 if (orig_ifinfo->last_seqno_forwarded == ntohl(ogm_received->seqno))
363 goto out;
364
365 orig_ifinfo->last_seqno_forwarded = ntohl(ogm_received->seqno);
366
Antonio Quartulli93231582016-01-16 16:40:13 +0800367 if (ogm_received->ttl <= 1) {
368 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100369 goto out;
Antonio Quartulli93231582016-01-16 16:40:13 +0800370 }
371
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100372 neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
373 if (!neigh_ifinfo)
374 goto out;
375
Antonio Quartulli93231582016-01-16 16:40:13 +0800376 tvlv_len = ntohs(ogm_received->tvlv_len);
377
378 packet_len = BATADV_OGM2_HLEN + tvlv_len;
379 skb = netdev_alloc_skb_ip_align(if_outgoing->net_dev,
380 ETH_HLEN + packet_len);
381 if (!skb)
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100382 goto out;
Antonio Quartulli93231582016-01-16 16:40:13 +0800383
384 skb_reserve(skb, ETH_HLEN);
385 skb_buff = skb_put(skb, packet_len);
386 memcpy(skb_buff, ogm_received, packet_len);
387
388 /* apply forward penalty */
389 ogm_forward = (struct batadv_ogm2_packet *)skb_buff;
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100390 ogm_forward->throughput = htonl(neigh_ifinfo->bat_v.throughput);
Antonio Quartulli93231582016-01-16 16:40:13 +0800391 ogm_forward->ttl--;
392
393 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
394 "Forwarding OGM2 packet on %s: throughput %u, ttl %u, received via %s\n",
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100395 if_outgoing->net_dev->name, ntohl(ogm_forward->throughput),
396 ogm_forward->ttl, if_incoming->net_dev->name);
Antonio Quartulli93231582016-01-16 16:40:13 +0800397
398 batadv_v_ogm_send_to_if(skb, if_outgoing);
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100399
400out:
401 if (orig_ifinfo)
402 batadv_orig_ifinfo_put(orig_ifinfo);
403 if (router)
404 batadv_neigh_node_put(router);
405 if (neigh_ifinfo)
406 batadv_neigh_ifinfo_put(neigh_ifinfo);
Antonio Quartulli93231582016-01-16 16:40:13 +0800407}
408
409/**
410 * batadv_v_ogm_metric_update - update route metric based on OGM
411 * @bat_priv: the bat priv with all the soft interface information
412 * @ogm2: OGM2 structure
413 * @orig_node: Originator structure for which the OGM has been received
414 * @neigh_node: the neigh_node through with the OGM has been received
415 * @if_incoming: the interface where this packet was received
416 * @if_outgoing: the interface for which the packet should be considered
417 *
418 * Return:
419 * 1 if the OGM is new,
420 * 0 if it is not new but valid,
421 * <0 on error (e.g. old OGM)
422 */
423static int batadv_v_ogm_metric_update(struct batadv_priv *bat_priv,
424 const struct batadv_ogm2_packet *ogm2,
425 struct batadv_orig_node *orig_node,
426 struct batadv_neigh_node *neigh_node,
427 struct batadv_hard_iface *if_incoming,
428 struct batadv_hard_iface *if_outgoing)
429{
Sven Eckelmann422d2f72016-07-25 00:42:44 +0200430 struct batadv_orig_ifinfo *orig_ifinfo;
Antonio Quartulli93231582016-01-16 16:40:13 +0800431 struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
432 bool protection_started = false;
433 int ret = -EINVAL;
434 u32 path_throughput;
435 s32 seq_diff;
436
437 orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
438 if (!orig_ifinfo)
439 goto out;
440
441 seq_diff = ntohl(ogm2->seqno) - orig_ifinfo->last_real_seqno;
442
443 if (!hlist_empty(&orig_node->neigh_list) &&
444 batadv_window_protected(bat_priv, seq_diff,
445 BATADV_OGM_MAX_AGE,
446 &orig_ifinfo->batman_seqno_reset,
447 &protection_started)) {
448 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
449 "Drop packet: packet within window protection time from %pM\n",
450 ogm2->orig);
451 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
452 "Last reset: %ld, %ld\n",
453 orig_ifinfo->batman_seqno_reset, jiffies);
454 goto out;
455 }
456
457 /* drop packets with old seqnos, however accept the first packet after
458 * a host has been rebooted.
459 */
460 if ((seq_diff < 0) && !protection_started)
461 goto out;
462
463 neigh_node->last_seen = jiffies;
464
465 orig_node->last_seen = jiffies;
466
467 orig_ifinfo->last_real_seqno = ntohl(ogm2->seqno);
468 orig_ifinfo->last_ttl = ogm2->ttl;
469
470 neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
471 if (!neigh_ifinfo)
472 goto out;
473
474 path_throughput = batadv_v_forward_penalty(bat_priv, if_incoming,
475 if_outgoing,
476 ntohl(ogm2->throughput));
477 neigh_ifinfo->bat_v.throughput = path_throughput;
478 neigh_ifinfo->bat_v.last_seqno = ntohl(ogm2->seqno);
479 neigh_ifinfo->last_ttl = ogm2->ttl;
480
481 if (seq_diff > 0 || protection_started)
482 ret = 1;
483 else
484 ret = 0;
485out:
486 if (orig_ifinfo)
487 batadv_orig_ifinfo_put(orig_ifinfo);
488 if (neigh_ifinfo)
489 batadv_neigh_ifinfo_put(neigh_ifinfo);
490
491 return ret;
492}
493
494/**
495 * batadv_v_ogm_route_update - update routes based on OGM
496 * @bat_priv: the bat priv with all the soft interface information
497 * @ethhdr: the Ethernet header of the OGM2
498 * @ogm2: OGM2 structure
499 * @orig_node: Originator structure for which the OGM has been received
500 * @neigh_node: the neigh_node through with the OGM has been received
501 * @if_incoming: the interface where this packet was received
502 * @if_outgoing: the interface for which the packet should be considered
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100503 *
504 * Return: true if the packet should be forwarded, false otherwise
Antonio Quartulli93231582016-01-16 16:40:13 +0800505 */
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100506static bool batadv_v_ogm_route_update(struct batadv_priv *bat_priv,
Antonio Quartulli93231582016-01-16 16:40:13 +0800507 const struct ethhdr *ethhdr,
508 const struct batadv_ogm2_packet *ogm2,
509 struct batadv_orig_node *orig_node,
510 struct batadv_neigh_node *neigh_node,
511 struct batadv_hard_iface *if_incoming,
512 struct batadv_hard_iface *if_outgoing)
513{
514 struct batadv_neigh_node *router = NULL;
Sven Eckelmann422d2f72016-07-25 00:42:44 +0200515 struct batadv_orig_node *orig_neigh_node;
Antonio Quartulli93231582016-01-16 16:40:13 +0800516 struct batadv_neigh_node *orig_neigh_router = NULL;
Simon Wunderlich86de37c2016-02-01 15:21:38 +0100517 struct batadv_neigh_ifinfo *router_ifinfo = NULL, *neigh_ifinfo = NULL;
518 u32 router_throughput, neigh_throughput;
519 u32 router_last_seqno;
520 u32 neigh_last_seqno;
521 s32 neigh_seq_diff;
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100522 bool forward = false;
Antonio Quartulli93231582016-01-16 16:40:13 +0800523
524 orig_neigh_node = batadv_v_ogm_orig_get(bat_priv, ethhdr->h_source);
525 if (!orig_neigh_node)
526 goto out;
527
528 orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
529 if_outgoing);
530
531 /* drop packet if sender is not a direct neighbor and if we
532 * don't route towards it
533 */
534 router = batadv_orig_router_get(orig_node, if_outgoing);
535 if (router && router->orig_node != orig_node && !orig_neigh_router) {
536 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
537 "Drop packet: OGM via unknown neighbor!\n");
538 goto out;
539 }
540
Simon Wunderlich86de37c2016-02-01 15:21:38 +0100541 /* Mark the OGM to be considered for forwarding, and update routes
542 * if needed.
543 */
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100544 forward = true;
Simon Wunderlich86de37c2016-02-01 15:21:38 +0100545
546 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
547 "Searching and updating originator entry of received packet\n");
548
549 /* if this neighbor already is our next hop there is nothing
550 * to change
551 */
552 if (router == neigh_node)
553 goto out;
554
555 /* don't consider neighbours with worse throughput.
556 * also switch route if this seqno is BATADV_V_MAX_ORIGDIFF newer than
557 * the last received seqno from our best next hop.
558 */
559 if (router) {
560 router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
561 neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
562
563 /* if these are not allocated, something is wrong. */
564 if (!router_ifinfo || !neigh_ifinfo)
565 goto out;
566
567 neigh_last_seqno = neigh_ifinfo->bat_v.last_seqno;
568 router_last_seqno = router_ifinfo->bat_v.last_seqno;
569 neigh_seq_diff = neigh_last_seqno - router_last_seqno;
570 router_throughput = router_ifinfo->bat_v.throughput;
571 neigh_throughput = neigh_ifinfo->bat_v.throughput;
572
573 if ((neigh_seq_diff < BATADV_OGM_MAX_ORIGDIFF) &&
574 (router_throughput >= neigh_throughput))
575 goto out;
576 }
577
578 batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
Antonio Quartulli93231582016-01-16 16:40:13 +0800579out:
Antonio Quartulli93231582016-01-16 16:40:13 +0800580 if (router)
581 batadv_neigh_node_put(router);
582 if (orig_neigh_router)
583 batadv_neigh_node_put(orig_neigh_router);
584 if (orig_neigh_node)
585 batadv_orig_node_put(orig_neigh_node);
Simon Wunderlich86de37c2016-02-01 15:21:38 +0100586 if (router_ifinfo)
587 batadv_neigh_ifinfo_put(router_ifinfo);
588 if (neigh_ifinfo)
589 batadv_neigh_ifinfo_put(neigh_ifinfo);
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100590
591 return forward;
Antonio Quartulli93231582016-01-16 16:40:13 +0800592}
593
594/**
595 * batadv_v_ogm_process_per_outif - process a batman v OGM for an outgoing if
596 * @bat_priv: the bat priv with all the soft interface information
597 * @ethhdr: the Ethernet header of the OGM2
598 * @ogm2: OGM2 structure
599 * @orig_node: Originator structure for which the OGM has been received
600 * @neigh_node: the neigh_node through with the OGM has been received
601 * @if_incoming: the interface where this packet was received
602 * @if_outgoing: the interface for which the packet should be considered
603 */
604static void
605batadv_v_ogm_process_per_outif(struct batadv_priv *bat_priv,
606 const struct ethhdr *ethhdr,
607 const struct batadv_ogm2_packet *ogm2,
608 struct batadv_orig_node *orig_node,
609 struct batadv_neigh_node *neigh_node,
610 struct batadv_hard_iface *if_incoming,
611 struct batadv_hard_iface *if_outgoing)
612{
613 int seqno_age;
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100614 bool forward;
Antonio Quartulli93231582016-01-16 16:40:13 +0800615
616 /* first, update the metric with according sanity checks */
617 seqno_age = batadv_v_ogm_metric_update(bat_priv, ogm2, orig_node,
618 neigh_node, if_incoming,
619 if_outgoing);
620
621 /* outdated sequence numbers are to be discarded */
622 if (seqno_age < 0)
623 return;
624
625 /* only unknown & newer OGMs contain TVLVs we are interested in */
626 if ((seqno_age > 0) && (if_outgoing == BATADV_IF_DEFAULT))
627 batadv_tvlv_containers_process(bat_priv, true, orig_node,
628 NULL, NULL,
629 (unsigned char *)(ogm2 + 1),
630 ntohs(ogm2->tvlv_len));
631
632 /* if the metric update went through, update routes if needed */
Simon Wunderlichefcc9d302016-02-01 15:21:37 +0100633 forward = batadv_v_ogm_route_update(bat_priv, ethhdr, ogm2, orig_node,
634 neigh_node, if_incoming,
635 if_outgoing);
636
637 /* if the routes have been processed correctly, check and forward */
638 if (forward)
639 batadv_v_ogm_forward(bat_priv, ogm2, orig_node, neigh_node,
640 if_incoming, if_outgoing);
Antonio Quartulli93231582016-01-16 16:40:13 +0800641}
642
643/**
644 * batadv_v_ogm_aggr_packet - checks if there is another OGM aggregated
645 * @buff_pos: current position in the skb
646 * @packet_len: total length of the skb
647 * @tvlv_len: tvlv length of the previously considered OGM
648 *
649 * Return: true if there is enough space for another OGM, false otherwise.
650 */
651static bool batadv_v_ogm_aggr_packet(int buff_pos, int packet_len,
652 __be16 tvlv_len)
653{
654 int next_buff_pos = 0;
655
656 next_buff_pos += buff_pos + BATADV_OGM2_HLEN;
657 next_buff_pos += ntohs(tvlv_len);
658
659 return (next_buff_pos <= packet_len) &&
660 (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
661}
662
663/**
664 * batadv_v_ogm_process - process an incoming batman v OGM
665 * @skb: the skb containing the OGM
666 * @ogm_offset: offset to the OGM which should be processed (for aggregates)
667 * @if_incoming: the interface where this packet was receved
668 */
669static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset,
670 struct batadv_hard_iface *if_incoming)
671{
672 struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
673 struct ethhdr *ethhdr;
674 struct batadv_orig_node *orig_node = NULL;
675 struct batadv_hardif_neigh_node *hardif_neigh = NULL;
676 struct batadv_neigh_node *neigh_node = NULL;
677 struct batadv_hard_iface *hard_iface;
678 struct batadv_ogm2_packet *ogm_packet;
679 u32 ogm_throughput, link_throughput, path_throughput;
Linus Lüssing3111bee2016-08-07 12:34:19 +0200680 int ret;
Antonio Quartulli93231582016-01-16 16:40:13 +0800681
682 ethhdr = eth_hdr(skb);
683 ogm_packet = (struct batadv_ogm2_packet *)(skb->data + ogm_offset);
684
685 ogm_throughput = ntohl(ogm_packet->throughput);
686
687 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
688 "Received OGM2 packet via NB: %pM, IF: %s [%pM] (from OG: %pM, seqno %u, troughput %u, TTL %u, V %u, tvlv_len %u)\n",
689 ethhdr->h_source, if_incoming->net_dev->name,
690 if_incoming->net_dev->dev_addr, ogm_packet->orig,
691 ntohl(ogm_packet->seqno), ogm_throughput, ogm_packet->ttl,
692 ogm_packet->version, ntohs(ogm_packet->tvlv_len));
693
694 /* If the troughput metric is 0, immediately drop the packet. No need to
695 * create orig_node / neigh_node for an unusable route.
696 */
697 if (ogm_throughput == 0) {
698 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
699 "Drop packet: originator packet with troughput metric of 0\n");
700 return;
701 }
702
703 /* require ELP packets be to received from this neighbor first */
704 hardif_neigh = batadv_hardif_neigh_get(if_incoming, ethhdr->h_source);
705 if (!hardif_neigh) {
706 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
707 "Drop packet: OGM via unknown neighbor!\n");
708 goto out;
709 }
710
711 orig_node = batadv_v_ogm_orig_get(bat_priv, ogm_packet->orig);
712 if (!orig_node)
713 return;
714
Marek Lindner6f0a6b52016-05-03 01:52:08 +0800715 neigh_node = batadv_neigh_node_get_or_create(orig_node, if_incoming,
716 ethhdr->h_source);
Antonio Quartulli93231582016-01-16 16:40:13 +0800717 if (!neigh_node)
718 goto out;
719
720 /* Update the received throughput metric to match the link
721 * characteristic:
722 * - If this OGM traveled one hop so far (emitted by single hop
723 * neighbor) the path throughput metric equals the link throughput.
724 * - For OGMs traversing more than hop the path throughput metric is
725 * the smaller of the path throughput and the link throughput.
726 */
727 link_throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput);
728 path_throughput = min_t(u32, link_throughput, ogm_throughput);
729 ogm_packet->throughput = htonl(path_throughput);
730
731 batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet, orig_node,
732 neigh_node, if_incoming,
733 BATADV_IF_DEFAULT);
734
735 rcu_read_lock();
736 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
737 if (hard_iface->if_status != BATADV_IF_ACTIVE)
738 continue;
739
740 if (hard_iface->soft_iface != bat_priv->soft_iface)
741 continue;
742
Sven Eckelmann27353442016-03-05 16:09:16 +0100743 if (!kref_get_unless_zero(&hard_iface->refcount))
744 continue;
745
Linus Lüssing3111bee2016-08-07 12:34:19 +0200746 ret = batadv_hardif_no_broadcast(hard_iface,
747 ogm_packet->orig,
748 hardif_neigh->orig);
749
750 if (ret) {
751 char *type;
752
753 switch (ret) {
754 case BATADV_HARDIF_BCAST_NORECIPIENT:
755 type = "no neighbor";
756 break;
757 case BATADV_HARDIF_BCAST_DUPFWD:
758 type = "single neighbor is source";
759 break;
760 case BATADV_HARDIF_BCAST_DUPORIG:
761 type = "single neighbor is originator";
762 break;
763 default:
764 type = "unknown";
765 }
766
767 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "OGM2 packet from %pM on %s surpressed: %s\n",
768 ogm_packet->orig, hard_iface->net_dev->name,
769 type);
770
771 batadv_hardif_put(hard_iface);
772 continue;
773 }
774
Antonio Quartulli93231582016-01-16 16:40:13 +0800775 batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet,
776 orig_node, neigh_node,
777 if_incoming, hard_iface);
Sven Eckelmann27353442016-03-05 16:09:16 +0100778
779 batadv_hardif_put(hard_iface);
Antonio Quartulli93231582016-01-16 16:40:13 +0800780 }
781 rcu_read_unlock();
782out:
783 if (orig_node)
784 batadv_orig_node_put(orig_node);
785 if (neigh_node)
786 batadv_neigh_node_put(neigh_node);
787 if (hardif_neigh)
788 batadv_hardif_neigh_put(hardif_neigh);
789}
790
791/**
Antonio Quartulli0da00352016-01-16 16:40:12 +0800792 * batadv_v_ogm_packet_recv - OGM2 receiving handler
793 * @skb: the received OGM
794 * @if_incoming: the interface where this OGM has been received
795 *
796 * Return: NET_RX_SUCCESS and consume the skb on success or returns NET_RX_DROP
797 * (without freeing the skb) on failure
798 */
799int batadv_v_ogm_packet_recv(struct sk_buff *skb,
800 struct batadv_hard_iface *if_incoming)
801{
802 struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
803 struct batadv_ogm2_packet *ogm_packet;
804 struct ethhdr *ethhdr = eth_hdr(skb);
Antonio Quartulli93231582016-01-16 16:40:13 +0800805 int ogm_offset;
806 u8 *packet_pos;
807 int ret = NET_RX_DROP;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800808
809 /* did we receive a OGM2 packet on an interface that does not have
810 * B.A.T.M.A.N. V enabled ?
811 */
Antonio Quartulli29824a52016-05-25 23:27:31 +0800812 if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0)
Sven Eckelmannb91a2542016-07-17 21:04:04 +0200813 goto free_skb;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800814
815 if (!batadv_check_management_packet(skb, if_incoming, BATADV_OGM2_HLEN))
Sven Eckelmannb91a2542016-07-17 21:04:04 +0200816 goto free_skb;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800817
818 if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
Sven Eckelmannb91a2542016-07-17 21:04:04 +0200819 goto free_skb;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800820
821 ogm_packet = (struct batadv_ogm2_packet *)skb->data;
822
823 if (batadv_is_my_mac(bat_priv, ogm_packet->orig))
Sven Eckelmannb91a2542016-07-17 21:04:04 +0200824 goto free_skb;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800825
826 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
827 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
828 skb->len + ETH_HLEN);
829
Antonio Quartulli93231582016-01-16 16:40:13 +0800830 ogm_offset = 0;
831 ogm_packet = (struct batadv_ogm2_packet *)skb->data;
832
833 while (batadv_v_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
834 ogm_packet->tvlv_len)) {
835 batadv_v_ogm_process(skb, ogm_offset, if_incoming);
836
837 ogm_offset += BATADV_OGM2_HLEN;
838 ogm_offset += ntohs(ogm_packet->tvlv_len);
839
840 packet_pos = skb->data + ogm_offset;
841 ogm_packet = (struct batadv_ogm2_packet *)packet_pos;
842 }
843
844 ret = NET_RX_SUCCESS;
Sven Eckelmannb91a2542016-07-17 21:04:04 +0200845
846free_skb:
847 if (ret == NET_RX_SUCCESS)
848 consume_skb(skb);
849 else
850 kfree_skb(skb);
Antonio Quartulli93231582016-01-16 16:40:13 +0800851
852 return ret;
Antonio Quartulli0da00352016-01-16 16:40:12 +0800853}
854
855/**
856 * batadv_v_ogm_init - initialise the OGM2 engine
857 * @bat_priv: the bat priv with all the soft interface information
858 *
859 * Return: 0 on success or a negative error code in case of failure
860 */
861int batadv_v_ogm_init(struct batadv_priv *bat_priv)
862{
863 struct batadv_ogm2_packet *ogm_packet;
864 unsigned char *ogm_buff;
865 u32 random_seqno;
866
867 bat_priv->bat_v.ogm_buff_len = BATADV_OGM2_HLEN;
868 ogm_buff = kzalloc(bat_priv->bat_v.ogm_buff_len, GFP_ATOMIC);
869 if (!ogm_buff)
870 return -ENOMEM;
871
872 bat_priv->bat_v.ogm_buff = ogm_buff;
873 ogm_packet = (struct batadv_ogm2_packet *)ogm_buff;
874 ogm_packet->packet_type = BATADV_OGM2;
875 ogm_packet->version = BATADV_COMPAT_VERSION;
876 ogm_packet->ttl = BATADV_TTL;
877 ogm_packet->flags = BATADV_NO_FLAGS;
878 ogm_packet->throughput = htonl(BATADV_THROUGHPUT_MAX_VALUE);
879
880 /* randomize initial seqno to avoid collision */
881 get_random_bytes(&random_seqno, sizeof(random_seqno));
882 atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno);
883 INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send);
884
885 return 0;
886}
887
888/**
889 * batadv_v_ogm_free - free OGM private resources
890 * @bat_priv: the bat priv with all the soft interface information
891 */
892void batadv_v_ogm_free(struct batadv_priv *bat_priv)
893{
894 cancel_delayed_work_sync(&bat_priv->bat_v.ogm_wq);
895
896 kfree(bat_priv->bat_v.ogm_buff);
897 bat_priv->bat_v.ogm_buff = NULL;
898 bat_priv->bat_v.ogm_buff_len = 0;
899}