blob: 7d170010beb9050ffbb90aff463c16cde60e144d [file] [log] [blame]
Linus Luessingd6f94d92016-01-16 16:40:09 +08001/* Copyright (C) 2011-2016 B.A.T.M.A.N. contributors:
2 *
3 * Linus Lüssing, Marek Lindner
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_elp.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>
Antonio Quartullic8334842015-11-10 18:50:51 +010025#include <linux/ethtool.h>
Linus Luessingd6f94d92016-01-16 16:40:09 +080026#include <linux/fs.h>
27#include <linux/if_ether.h>
28#include <linux/jiffies.h>
29#include <linux/kernel.h>
Antonio Quartullic8334842015-11-10 18:50:51 +010030#include <linux/kref.h>
Linus Luessingd6f94d92016-01-16 16:40:09 +080031#include <linux/netdevice.h>
32#include <linux/random.h>
33#include <linux/rculist.h>
34#include <linux/rcupdate.h>
Antonio Quartullic8334842015-11-10 18:50:51 +010035#include <linux/rtnetlink.h>
Linus Luessingd6f94d92016-01-16 16:40:09 +080036#include <linux/skbuff.h>
37#include <linux/stddef.h>
38#include <linux/string.h>
39#include <linux/types.h>
40#include <linux/workqueue.h>
Antonio Quartullic8334842015-11-10 18:50:51 +010041#include <net/cfg80211.h>
Linus Luessingd6f94d92016-01-16 16:40:09 +080042
43#include "bat_algo.h"
Antonio Quartulli93231582016-01-16 16:40:13 +080044#include "bat_v_ogm.h"
Linus Luessingd6f94d92016-01-16 16:40:09 +080045#include "hard-interface.h"
Sven Eckelmannba412082016-05-15 23:48:31 +020046#include "log.h"
Linus Luessing162bd642016-01-16 16:40:10 +080047#include "originator.h"
Linus Luessingd6f94d92016-01-16 16:40:09 +080048#include "packet.h"
Linus Luessing162bd642016-01-16 16:40:10 +080049#include "routing.h"
Linus Luessingd6f94d92016-01-16 16:40:09 +080050#include "send.h"
51
52/**
53 * batadv_v_elp_start_timer - restart timer for ELP periodic work
54 * @hard_iface: the interface for which the timer has to be reset
55 */
56static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface)
57{
58 unsigned int msecs;
59
60 msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER;
61 msecs += prandom_u32() % (2 * BATADV_JITTER);
62
63 queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq,
64 msecs_to_jiffies(msecs));
65}
66
67/**
Antonio Quartullic8334842015-11-10 18:50:51 +010068 * batadv_v_elp_get_throughput - get the throughput towards a neighbour
69 * @neigh: the neighbour for which the throughput has to be obtained
70 *
71 * Return: The throughput towards the given neighbour in multiples of 100kpbs
72 * (a value of '1' equals to 0.1Mbps, '10' equals 1Mbps, etc).
73 */
74static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
75{
76 struct batadv_hard_iface *hard_iface = neigh->if_incoming;
77 struct ethtool_link_ksettings link_settings;
78 struct station_info sinfo;
79 u32 throughput;
80 int ret;
81
82 /* if the user specified a customised value for this interface, then
83 * return it directly
84 */
85 throughput = atomic_read(&hard_iface->bat_v.throughput_override);
86 if (throughput != 0)
87 return throughput;
88
89 /* if this is a wireless device, then ask its throughput through
90 * cfg80211 API
91 */
92 if (batadv_is_wifi_netdev(hard_iface->net_dev)) {
93 if (hard_iface->net_dev->ieee80211_ptr) {
94 ret = cfg80211_get_station(hard_iface->net_dev,
95 neigh->addr, &sinfo);
96 if (ret == -ENOENT) {
97 /* Node is not associated anymore! It would be
98 * possible to delete this neighbor. For now set
99 * the throughput metric to 0.
100 */
101 return 0;
102 }
103 if (!ret)
104 return sinfo.expected_throughput / 100;
105 }
106
107 /* unsupported WiFi driver version */
108 goto default_throughput;
109 }
110
111 /* if not a wifi interface, check if this device provides data via
112 * ethtool (e.g. an Ethernet adapter)
113 */
114 memset(&link_settings, 0, sizeof(link_settings));
115 rtnl_lock();
116 ret = __ethtool_get_link_ksettings(hard_iface->net_dev, &link_settings);
117 rtnl_unlock();
118 if (ret == 0) {
119 /* link characteristics might change over time */
120 if (link_settings.base.duplex == DUPLEX_FULL)
121 hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
122 else
123 hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
124
125 throughput = link_settings.base.speed;
126 if (throughput && (throughput != SPEED_UNKNOWN))
127 return throughput * 10;
128 }
129
130default_throughput:
131 if (!(hard_iface->bat_v.flags & BATADV_WARNING_DEFAULT)) {
132 batadv_info(hard_iface->soft_iface,
133 "WiFi driver or ethtool info does not provide information about link speeds on interface %s, therefore defaulting to hardcoded throughput values of %u.%1u Mbps. Consider overriding the throughput manually or checking your driver.\n",
134 hard_iface->net_dev->name,
135 BATADV_THROUGHPUT_DEFAULT_VALUE / 10,
136 BATADV_THROUGHPUT_DEFAULT_VALUE % 10);
137 hard_iface->bat_v.flags |= BATADV_WARNING_DEFAULT;
138 }
139
140 /* if none of the above cases apply, return the base_throughput */
141 return BATADV_THROUGHPUT_DEFAULT_VALUE;
142}
143
144/**
145 * batadv_v_elp_throughput_metric_update - worker updating the throughput metric
146 * of a single hop neighbour
147 * @work: the work queue item
148 */
149void batadv_v_elp_throughput_metric_update(struct work_struct *work)
150{
151 struct batadv_hardif_neigh_node_bat_v *neigh_bat_v;
152 struct batadv_hardif_neigh_node *neigh;
153
154 neigh_bat_v = container_of(work, struct batadv_hardif_neigh_node_bat_v,
155 metric_work);
156 neigh = container_of(neigh_bat_v, struct batadv_hardif_neigh_node,
157 bat_v);
158
159 ewma_throughput_add(&neigh->bat_v.throughput,
160 batadv_v_elp_get_throughput(neigh));
161
162 /* decrement refcounter to balance increment performed before scheduling
163 * this task
164 */
165 batadv_hardif_neigh_put(neigh);
166}
167
168/**
Antonio Quartulli8d2d4992015-11-10 18:51:22 +0100169 * batadv_v_elp_wifi_neigh_probe - send link probing packets to a neighbour
170 * @neigh: the neighbour to probe
171 *
172 * Sends a predefined number of unicast wifi packets to a given neighbour in
173 * order to trigger the throughput estimation on this link by the RC algorithm.
174 * Packets are sent only if there there is not enough payload unicast traffic
175 * towards this neighbour..
176 *
177 * Return: True on success and false in case of error during skb preparation.
178 */
179static bool
180batadv_v_elp_wifi_neigh_probe(struct batadv_hardif_neigh_node *neigh)
181{
182 struct batadv_hard_iface *hard_iface = neigh->if_incoming;
183 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
184 unsigned long last_tx_diff;
185 struct sk_buff *skb;
186 int probe_len, i;
187 int elp_skb_len;
188
189 /* this probing routine is for Wifi neighbours only */
190 if (!batadv_is_wifi_netdev(hard_iface->net_dev))
191 return true;
192
193 /* probe the neighbor only if no unicast packets have been sent
194 * to it in the last 100 milliseconds: this is the rate control
195 * algorithm sampling interval (minstrel). In this way, if not
196 * enough traffic has been sent to the neighbor, batman-adv can
197 * generate 2 probe packets and push the RC algorithm to perform
198 * the sampling
199 */
200 last_tx_diff = jiffies_to_msecs(jiffies - neigh->bat_v.last_unicast_tx);
201 if (last_tx_diff <= BATADV_ELP_PROBE_MAX_TX_DIFF)
202 return true;
203
204 probe_len = max_t(int, sizeof(struct batadv_elp_packet),
205 BATADV_ELP_MIN_PROBE_SIZE);
206
207 for (i = 0; i < BATADV_ELP_PROBES_PER_NODE; i++) {
208 elp_skb_len = hard_iface->bat_v.elp_skb->len;
209 skb = skb_copy_expand(hard_iface->bat_v.elp_skb, 0,
210 probe_len - elp_skb_len,
211 GFP_ATOMIC);
212 if (!skb)
213 return false;
214
215 /* Tell the skb to get as big as the allocated space (we want
216 * the packet to be exactly of that size to make the link
217 * throughput estimation effective.
218 */
219 skb_put(skb, probe_len - hard_iface->bat_v.elp_skb->len);
220
221 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
222 "Sending unicast (probe) ELP packet on interface %s to %pM\n",
223 hard_iface->net_dev->name, neigh->addr);
224
225 batadv_send_skb_packet(skb, hard_iface, neigh->addr);
226 }
227
228 return true;
229}
230
231/**
Linus Luessingd6f94d92016-01-16 16:40:09 +0800232 * batadv_v_elp_periodic_work - ELP periodic task per interface
233 * @work: work queue item
234 *
235 * Emits broadcast ELP message in regular intervals.
236 */
237static void batadv_v_elp_periodic_work(struct work_struct *work)
238{
Antonio Quartullic8334842015-11-10 18:50:51 +0100239 struct batadv_hardif_neigh_node *hardif_neigh;
Linus Luessingd6f94d92016-01-16 16:40:09 +0800240 struct batadv_hard_iface *hard_iface;
241 struct batadv_hard_iface_bat_v *bat_v;
242 struct batadv_elp_packet *elp_packet;
243 struct batadv_priv *bat_priv;
244 struct sk_buff *skb;
245 u32 elp_interval;
246
247 bat_v = container_of(work, struct batadv_hard_iface_bat_v, elp_wq.work);
248 hard_iface = container_of(bat_v, struct batadv_hard_iface, bat_v);
249 bat_priv = netdev_priv(hard_iface->soft_iface);
250
251 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
252 goto out;
253
254 /* we are in the process of shutting this interface down */
255 if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
256 (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
257 goto out;
258
259 /* the interface was enabled but may not be ready yet */
260 if (hard_iface->if_status != BATADV_IF_ACTIVE)
261 goto restart_timer;
262
263 skb = skb_copy(hard_iface->bat_v.elp_skb, GFP_ATOMIC);
264 if (!skb)
265 goto restart_timer;
266
267 elp_packet = (struct batadv_elp_packet *)skb->data;
268 elp_packet->seqno = htonl(atomic_read(&hard_iface->bat_v.elp_seqno));
269 elp_interval = atomic_read(&hard_iface->bat_v.elp_interval);
270 elp_packet->elp_interval = htonl(elp_interval);
271
272 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
273 "Sending broadcast ELP packet on interface %s, seqno %u\n",
274 hard_iface->net_dev->name,
275 atomic_read(&hard_iface->bat_v.elp_seqno));
276
Antonio Quartulli95d39272016-01-16 16:40:15 +0800277 batadv_send_broadcast_skb(skb, hard_iface);
Linus Luessingd6f94d92016-01-16 16:40:09 +0800278
279 atomic_inc(&hard_iface->bat_v.elp_seqno);
280
Antonio Quartullic8334842015-11-10 18:50:51 +0100281 /* The throughput metric is updated on each sent packet. This way, if a
282 * node is dead and no longer sends packets, batman-adv is still able to
283 * react timely to its death.
284 *
285 * The throughput metric is updated by following these steps:
286 * 1) if the hard_iface is wifi => send a number of unicast ELPs for
287 * probing/sampling to each neighbor
288 * 2) update the throughput metric value of each neighbor (note that the
289 * value retrieved in this step might be 100ms old because the
290 * probing packets at point 1) could still be in the HW queue)
291 */
292 rcu_read_lock();
293 hlist_for_each_entry_rcu(hardif_neigh, &hard_iface->neigh_list, list) {
Antonio Quartulli8d2d4992015-11-10 18:51:22 +0100294 if (!batadv_v_elp_wifi_neigh_probe(hardif_neigh))
295 /* if something goes wrong while probing, better to stop
296 * sending packets immediately and reschedule the task
297 */
298 break;
299
Antonio Quartullic8334842015-11-10 18:50:51 +0100300 if (!kref_get_unless_zero(&hardif_neigh->refcount))
301 continue;
302
303 /* Reading the estimated throughput from cfg80211 is a task that
304 * may sleep and that is not allowed in an rcu protected
305 * context. Therefore schedule a task for that.
306 */
307 queue_work(batadv_event_workqueue,
308 &hardif_neigh->bat_v.metric_work);
309 }
310 rcu_read_unlock();
311
Linus Luessingd6f94d92016-01-16 16:40:09 +0800312restart_timer:
313 batadv_v_elp_start_timer(hard_iface);
314out:
315 return;
316}
317
318/**
319 * batadv_v_elp_iface_enable - setup the ELP interface private resources
320 * @hard_iface: interface for which the data has to be prepared
321 *
322 * Return: 0 on success or a -ENOMEM in case of failure.
323 */
324int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface)
325{
326 struct batadv_elp_packet *elp_packet;
327 unsigned char *elp_buff;
328 u32 random_seqno;
329 size_t size;
330 int res = -ENOMEM;
331
332 size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN;
333 hard_iface->bat_v.elp_skb = dev_alloc_skb(size);
334 if (!hard_iface->bat_v.elp_skb)
335 goto out;
336
337 skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN);
338 elp_buff = skb_push(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN);
339 elp_packet = (struct batadv_elp_packet *)elp_buff;
340 memset(elp_packet, 0, BATADV_ELP_HLEN);
341
342 elp_packet->packet_type = BATADV_ELP;
343 elp_packet->version = BATADV_COMPAT_VERSION;
344
345 /* randomize initial seqno to avoid collision */
346 get_random_bytes(&random_seqno, sizeof(random_seqno));
347 atomic_set(&hard_iface->bat_v.elp_seqno, random_seqno);
Linus Luessingd6f94d92016-01-16 16:40:09 +0800348
Antonio Quartullic8334842015-11-10 18:50:51 +0100349 /* assume full-duplex by default */
350 hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
351
352 /* warn the user (again) if there is no throughput data is available */
353 hard_iface->bat_v.flags &= ~BATADV_WARNING_DEFAULT;
354
355 if (batadv_is_wifi_netdev(hard_iface->net_dev))
356 hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
357
Linus Luessingd6f94d92016-01-16 16:40:09 +0800358 INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq,
359 batadv_v_elp_periodic_work);
360 batadv_v_elp_start_timer(hard_iface);
361 res = 0;
362
363out:
364 return res;
365}
366
367/**
368 * batadv_v_elp_iface_disable - release ELP interface private resources
369 * @hard_iface: interface for which the resources have to be released
370 */
371void batadv_v_elp_iface_disable(struct batadv_hard_iface *hard_iface)
372{
373 cancel_delayed_work_sync(&hard_iface->bat_v.elp_wq);
374
375 dev_kfree_skb(hard_iface->bat_v.elp_skb);
376 hard_iface->bat_v.elp_skb = NULL;
377}
378
379/**
Marek Lindnerebe24ce2016-05-07 19:54:17 +0800380 * batadv_v_elp_iface_activate - update the ELP buffer belonging to the given
381 * hard-interface
382 * @primary_iface: the new primary interface
383 * @hard_iface: interface holding the to-be-updated buffer
384 */
385void batadv_v_elp_iface_activate(struct batadv_hard_iface *primary_iface,
386 struct batadv_hard_iface *hard_iface)
387{
388 struct batadv_elp_packet *elp_packet;
389 struct sk_buff *skb;
390
391 if (!hard_iface->bat_v.elp_skb)
392 return;
393
394 skb = hard_iface->bat_v.elp_skb;
395 elp_packet = (struct batadv_elp_packet *)skb->data;
396 ether_addr_copy(elp_packet->orig,
397 primary_iface->net_dev->dev_addr);
398}
399
400/**
Linus Luessingd6f94d92016-01-16 16:40:09 +0800401 * batadv_v_elp_primary_iface_set - change internal data to reflect the new
402 * primary interface
403 * @primary_iface: the new primary interface
404 */
405void batadv_v_elp_primary_iface_set(struct batadv_hard_iface *primary_iface)
406{
407 struct batadv_hard_iface *hard_iface;
Linus Luessingd6f94d92016-01-16 16:40:09 +0800408
409 /* update orig field of every elp iface belonging to this mesh */
410 rcu_read_lock();
411 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
412 if (primary_iface->soft_iface != hard_iface->soft_iface)
413 continue;
414
Marek Lindnerebe24ce2016-05-07 19:54:17 +0800415 batadv_v_elp_iface_activate(primary_iface, hard_iface);
Linus Luessingd6f94d92016-01-16 16:40:09 +0800416 }
417 rcu_read_unlock();
418}
Linus Luessing162bd642016-01-16 16:40:10 +0800419
420/**
Linus Luessing162bd642016-01-16 16:40:10 +0800421 * batadv_v_elp_neigh_update - update an ELP neighbour node
422 * @bat_priv: the bat priv with all the soft interface information
423 * @neigh_addr: the neighbour interface address
424 * @if_incoming: the interface the packet was received through
425 * @elp_packet: the received ELP packet
426 *
427 * Updates the ELP neighbour node state with the data received within the new
428 * ELP packet.
429 */
430static void batadv_v_elp_neigh_update(struct batadv_priv *bat_priv,
431 u8 *neigh_addr,
432 struct batadv_hard_iface *if_incoming,
433 struct batadv_elp_packet *elp_packet)
434
435{
436 struct batadv_neigh_node *neigh;
437 struct batadv_orig_node *orig_neigh;
438 struct batadv_hardif_neigh_node *hardif_neigh;
439 s32 seqno_diff;
440 s32 elp_latest_seqno;
441
442 orig_neigh = batadv_v_ogm_orig_get(bat_priv, elp_packet->orig);
443 if (!orig_neigh)
444 return;
445
Marek Lindner6f0a6b52016-05-03 01:52:08 +0800446 neigh = batadv_neigh_node_get_or_create(orig_neigh,
447 if_incoming, neigh_addr);
Linus Luessing162bd642016-01-16 16:40:10 +0800448 if (!neigh)
449 goto orig_free;
450
451 hardif_neigh = batadv_hardif_neigh_get(if_incoming, neigh_addr);
452 if (!hardif_neigh)
453 goto neigh_free;
454
455 elp_latest_seqno = hardif_neigh->bat_v.elp_latest_seqno;
456 seqno_diff = ntohl(elp_packet->seqno) - elp_latest_seqno;
457
458 /* known or older sequence numbers are ignored. However always adopt
459 * if the router seems to have been restarted.
460 */
461 if (seqno_diff < 1 && seqno_diff > -BATADV_ELP_MAX_AGE)
462 goto hardif_free;
463
464 neigh->last_seen = jiffies;
465 hardif_neigh->last_seen = jiffies;
466 hardif_neigh->bat_v.elp_latest_seqno = ntohl(elp_packet->seqno);
467 hardif_neigh->bat_v.elp_interval = ntohl(elp_packet->elp_interval);
468
469hardif_free:
470 if (hardif_neigh)
471 batadv_hardif_neigh_put(hardif_neigh);
472neigh_free:
473 if (neigh)
474 batadv_neigh_node_put(neigh);
475orig_free:
476 if (orig_neigh)
477 batadv_orig_node_put(orig_neigh);
478}
479
480/**
481 * batadv_v_elp_packet_recv - main ELP packet handler
482 * @skb: the received packet
483 * @if_incoming: the interface this packet was received through
484 *
485 * Return: NET_RX_SUCCESS and consumes the skb if the packet was peoperly
486 * processed or NET_RX_DROP in case of failure.
487 */
488int batadv_v_elp_packet_recv(struct sk_buff *skb,
489 struct batadv_hard_iface *if_incoming)
490{
491 struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
492 struct batadv_elp_packet *elp_packet;
493 struct batadv_hard_iface *primary_if;
494 struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
495 bool ret;
496
497 ret = batadv_check_management_packet(skb, if_incoming, BATADV_ELP_HLEN);
498 if (!ret)
499 return NET_RX_DROP;
500
501 if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
502 return NET_RX_DROP;
503
504 /* did we receive a B.A.T.M.A.N. V ELP packet on an interface
505 * that does not have B.A.T.M.A.N. V ELP enabled ?
506 */
Antonio Quartulli29824a52016-05-25 23:27:31 +0800507 if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0)
Linus Luessing162bd642016-01-16 16:40:10 +0800508 return NET_RX_DROP;
509
510 elp_packet = (struct batadv_elp_packet *)skb->data;
511
512 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
513 "Received ELP packet from %pM seqno %u ORIG: %pM\n",
514 ethhdr->h_source, ntohl(elp_packet->seqno),
515 elp_packet->orig);
516
517 primary_if = batadv_primary_if_get_selected(bat_priv);
518 if (!primary_if)
519 goto out;
520
521 batadv_v_elp_neigh_update(bat_priv, ethhdr->h_source, if_incoming,
522 elp_packet);
523
524out:
525 if (primary_if)
526 batadv_hardif_put(primary_if);
527 consume_skb(skb);
528 return NET_RX_SUCCESS;
529}