Commit | Line | Data |
---|---|---|
0da00359 AQ |
1 | /* 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> | |
27353446 | 29 | #include <linux/kref.h> |
9323158e | 30 | #include <linux/list.h> |
0da00359 AQ |
31 | #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 | ||
01d350d1 | 42 | #include "bat_algo.h" |
0da00359 | 43 | #include "hard-interface.h" |
9323158e | 44 | #include "hash.h" |
ba412080 | 45 | #include "log.h" |
9323158e | 46 | #include "originator.h" |
0da00359 AQ |
47 | #include "packet.h" |
48 | #include "routing.h" | |
49 | #include "send.h" | |
50 | #include "translation-table.h" | |
1f8dce49 | 51 | #include "tvlv.h" |
0da00359 | 52 | |
9323158e AQ |
53 | /** |
54 | * 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 | */ | |
62 | struct 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 | ||
55db2d59 | 76 | kref_get(&orig_node->refcount); |
9323158e AQ |
77 | 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) { | |
55db2d59 | 81 | /* remove refcnt for newly created orig_node and hash entry */ |
9323158e AQ |
82 | 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 | ||
0da00359 AQ |
90 | /** |
91 | * batadv_v_ogm_start_timer - restart the OGM sending timer | |
92 | * @bat_priv: the bat priv with all the soft interface information | |
93 | */ | |
94 | static 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 | */ | |
114 | static 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 | ||
95d39278 | 126 | batadv_send_broadcast_skb(skb, hard_iface); |
0da00359 AQ |
127 | } |
128 | ||
129 | /** | |
130 | * batadv_v_ogm_send - periodic worker broadcasting the own OGM | |
131 | * @work: work queue item | |
132 | */ | |
133 | static 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; | |
143 | ||
144 | bat_v = container_of(work, struct batadv_priv_bat_v, ogm_wq.work); | |
145 | bat_priv = container_of(bat_v, struct batadv_priv, bat_v); | |
146 | ||
147 | if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) | |
148 | goto out; | |
149 | ||
150 | ogm_buff = bat_priv->bat_v.ogm_buff; | |
151 | ogm_buff_len = bat_priv->bat_v.ogm_buff_len; | |
152 | /* tt changes have to be committed before the tvlv data is | |
153 | * appended as it may alter the tt tvlv container | |
154 | */ | |
155 | batadv_tt_local_commit_changes(bat_priv); | |
156 | tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, &ogm_buff, | |
157 | &ogm_buff_len, | |
158 | BATADV_OGM2_HLEN); | |
159 | ||
160 | bat_priv->bat_v.ogm_buff = ogm_buff; | |
161 | bat_priv->bat_v.ogm_buff_len = ogm_buff_len; | |
162 | ||
163 | skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + ogm_buff_len); | |
164 | if (!skb) | |
165 | goto reschedule; | |
166 | ||
167 | skb_reserve(skb, ETH_HLEN); | |
168 | pkt_buff = skb_put(skb, ogm_buff_len); | |
169 | memcpy(pkt_buff, ogm_buff, ogm_buff_len); | |
170 | ||
171 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
172 | ogm_packet->seqno = htonl(atomic_read(&bat_priv->bat_v.ogm_seqno)); | |
173 | atomic_inc(&bat_priv->bat_v.ogm_seqno); | |
174 | ogm_packet->tvlv_len = htons(tvlv_len); | |
175 | ||
176 | /* broadcast on every interface */ | |
177 | rcu_read_lock(); | |
178 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { | |
179 | if (hard_iface->soft_iface != bat_priv->soft_iface) | |
180 | continue; | |
181 | ||
27353446 SE |
182 | if (!kref_get_unless_zero(&hard_iface->refcount)) |
183 | continue; | |
184 | ||
0da00359 AQ |
185 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, |
186 | "Sending own OGM2 packet (originator %pM, seqno %u, throughput %u, TTL %d) on interface %s [%pM]\n", | |
187 | ogm_packet->orig, ntohl(ogm_packet->seqno), | |
188 | ntohl(ogm_packet->throughput), ogm_packet->ttl, | |
189 | hard_iface->net_dev->name, | |
190 | hard_iface->net_dev->dev_addr); | |
191 | ||
192 | /* this skb gets consumed by batadv_v_ogm_send_to_if() */ | |
193 | skb_tmp = skb_clone(skb, GFP_ATOMIC); | |
27353446 SE |
194 | if (!skb_tmp) { |
195 | batadv_hardif_put(hard_iface); | |
0da00359 | 196 | break; |
27353446 | 197 | } |
0da00359 AQ |
198 | |
199 | batadv_v_ogm_send_to_if(skb_tmp, hard_iface); | |
27353446 | 200 | batadv_hardif_put(hard_iface); |
0da00359 AQ |
201 | } |
202 | rcu_read_unlock(); | |
203 | ||
204 | consume_skb(skb); | |
205 | ||
206 | reschedule: | |
207 | batadv_v_ogm_start_timer(bat_priv); | |
208 | out: | |
209 | return; | |
210 | } | |
211 | ||
212 | /** | |
213 | * batadv_v_ogm_iface_enable - prepare an interface for B.A.T.M.A.N. V | |
214 | * @hard_iface: the interface to prepare | |
215 | * | |
216 | * Takes care of scheduling own OGM sending routine for this interface. | |
217 | * | |
218 | * Return: 0 on success or a negative error code otherwise | |
219 | */ | |
220 | int batadv_v_ogm_iface_enable(struct batadv_hard_iface *hard_iface) | |
221 | { | |
222 | struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); | |
223 | ||
224 | batadv_v_ogm_start_timer(bat_priv); | |
225 | ||
226 | return 0; | |
227 | } | |
228 | ||
229 | /** | |
230 | * batadv_v_ogm_primary_iface_set - set a new primary interface | |
231 | * @primary_iface: the new primary interface | |
232 | */ | |
233 | void batadv_v_ogm_primary_iface_set(struct batadv_hard_iface *primary_iface) | |
234 | { | |
235 | struct batadv_priv *bat_priv = netdev_priv(primary_iface->soft_iface); | |
236 | struct batadv_ogm2_packet *ogm_packet; | |
237 | ||
238 | if (!bat_priv->bat_v.ogm_buff) | |
239 | return; | |
240 | ||
241 | ogm_packet = (struct batadv_ogm2_packet *)bat_priv->bat_v.ogm_buff; | |
242 | ether_addr_copy(ogm_packet->orig, primary_iface->net_dev->dev_addr); | |
243 | } | |
244 | ||
9323158e AQ |
245 | /** |
246 | * batadv_v_forward_penalty - apply a penalty to the throughput metric forwarded | |
247 | * with B.A.T.M.A.N. V OGMs | |
248 | * @bat_priv: the bat priv with all the soft interface information | |
249 | * @if_incoming: the interface where the OGM has been received | |
250 | * @if_outgoing: the interface where the OGM has to be forwarded to | |
251 | * @throughput: the current throughput | |
252 | * | |
253 | * Apply a penalty on the current throughput metric value based on the | |
254 | * characteristic of the interface where the OGM has been received. The return | |
255 | * value is computed as follows: | |
256 | * - throughput * 50% if the incoming and outgoing interface are the | |
257 | * same WiFi interface and the throughput is above | |
258 | * 1MBit/s | |
259 | * - throughput if the outgoing interface is the default | |
260 | * interface (i.e. this OGM is processed for the | |
261 | * internal table and not forwarded) | |
262 | * - throughput * hop penalty otherwise | |
263 | * | |
264 | * Return: the penalised throughput metric. | |
265 | */ | |
266 | static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv, | |
267 | struct batadv_hard_iface *if_incoming, | |
268 | struct batadv_hard_iface *if_outgoing, | |
269 | u32 throughput) | |
270 | { | |
271 | int hop_penalty = atomic_read(&bat_priv->hop_penalty); | |
272 | int hop_penalty_max = BATADV_TQ_MAX_VALUE; | |
273 | ||
274 | /* Don't apply hop penalty in default originator table. */ | |
275 | if (if_outgoing == BATADV_IF_DEFAULT) | |
276 | return throughput; | |
277 | ||
278 | /* Forwarding on the same WiFi interface cuts the throughput in half | |
279 | * due to the store & forward characteristics of WIFI. | |
280 | * Very low throughput values are the exception. | |
281 | */ | |
282 | if ((throughput > 10) && | |
283 | (if_incoming == if_outgoing) && | |
c833484e | 284 | !(if_incoming->bat_v.flags & BATADV_FULL_DUPLEX)) |
9323158e AQ |
285 | return throughput / 2; |
286 | ||
287 | /* hop penalty of 255 equals 100% */ | |
288 | return throughput * (hop_penalty_max - hop_penalty) / hop_penalty_max; | |
289 | } | |
290 | ||
291 | /** | |
efcc9d30 SW |
292 | * batadv_v_ogm_forward - check conditions and forward an OGM to the given |
293 | * outgoing interface | |
9323158e AQ |
294 | * @bat_priv: the bat priv with all the soft interface information |
295 | * @ogm_received: previously received OGM to be forwarded | |
efcc9d30 SW |
296 | * @orig_node: the originator which has been updated |
297 | * @neigh_node: the neigh_node through with the OGM has been received | |
9323158e AQ |
298 | * @if_incoming: the interface on which this OGM was received on |
299 | * @if_outgoing: the interface to which the OGM has to be forwarded to | |
300 | * | |
301 | * Forward an OGM to an interface after having altered the throughput metric and | |
302 | * the TTL value contained in it. The original OGM isn't modified. | |
303 | */ | |
304 | static void batadv_v_ogm_forward(struct batadv_priv *bat_priv, | |
305 | const struct batadv_ogm2_packet *ogm_received, | |
efcc9d30 SW |
306 | struct batadv_orig_node *orig_node, |
307 | struct batadv_neigh_node *neigh_node, | |
9323158e AQ |
308 | struct batadv_hard_iface *if_incoming, |
309 | struct batadv_hard_iface *if_outgoing) | |
310 | { | |
efcc9d30 SW |
311 | struct batadv_neigh_ifinfo *neigh_ifinfo = NULL; |
312 | struct batadv_orig_ifinfo *orig_ifinfo = NULL; | |
313 | struct batadv_neigh_node *router = NULL; | |
9323158e AQ |
314 | struct batadv_ogm2_packet *ogm_forward; |
315 | unsigned char *skb_buff; | |
316 | struct sk_buff *skb; | |
317 | size_t packet_len; | |
318 | u16 tvlv_len; | |
319 | ||
efcc9d30 SW |
320 | /* only forward for specific interfaces, not for the default one. */ |
321 | if (if_outgoing == BATADV_IF_DEFAULT) | |
322 | goto out; | |
323 | ||
324 | orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing); | |
325 | if (!orig_ifinfo) | |
326 | goto out; | |
327 | ||
328 | /* acquire possibly updated router */ | |
329 | router = batadv_orig_router_get(orig_node, if_outgoing); | |
330 | ||
331 | /* strict rule: forward packets coming from the best next hop only */ | |
332 | if (neigh_node != router) | |
333 | goto out; | |
334 | ||
335 | /* don't forward the same seqno twice on one interface */ | |
336 | if (orig_ifinfo->last_seqno_forwarded == ntohl(ogm_received->seqno)) | |
337 | goto out; | |
338 | ||
339 | orig_ifinfo->last_seqno_forwarded = ntohl(ogm_received->seqno); | |
340 | ||
9323158e AQ |
341 | if (ogm_received->ttl <= 1) { |
342 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n"); | |
efcc9d30 | 343 | goto out; |
9323158e AQ |
344 | } |
345 | ||
efcc9d30 SW |
346 | neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing); |
347 | if (!neigh_ifinfo) | |
348 | goto out; | |
349 | ||
9323158e AQ |
350 | tvlv_len = ntohs(ogm_received->tvlv_len); |
351 | ||
352 | packet_len = BATADV_OGM2_HLEN + tvlv_len; | |
353 | skb = netdev_alloc_skb_ip_align(if_outgoing->net_dev, | |
354 | ETH_HLEN + packet_len); | |
355 | if (!skb) | |
efcc9d30 | 356 | goto out; |
9323158e AQ |
357 | |
358 | skb_reserve(skb, ETH_HLEN); | |
359 | skb_buff = skb_put(skb, packet_len); | |
360 | memcpy(skb_buff, ogm_received, packet_len); | |
361 | ||
362 | /* apply forward penalty */ | |
363 | ogm_forward = (struct batadv_ogm2_packet *)skb_buff; | |
efcc9d30 | 364 | ogm_forward->throughput = htonl(neigh_ifinfo->bat_v.throughput); |
9323158e AQ |
365 | ogm_forward->ttl--; |
366 | ||
367 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
368 | "Forwarding OGM2 packet on %s: throughput %u, ttl %u, received via %s\n", | |
efcc9d30 SW |
369 | if_outgoing->net_dev->name, ntohl(ogm_forward->throughput), |
370 | ogm_forward->ttl, if_incoming->net_dev->name); | |
9323158e AQ |
371 | |
372 | batadv_v_ogm_send_to_if(skb, if_outgoing); | |
efcc9d30 SW |
373 | |
374 | out: | |
375 | if (orig_ifinfo) | |
376 | batadv_orig_ifinfo_put(orig_ifinfo); | |
377 | if (router) | |
378 | batadv_neigh_node_put(router); | |
379 | if (neigh_ifinfo) | |
380 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
9323158e AQ |
381 | } |
382 | ||
383 | /** | |
384 | * batadv_v_ogm_metric_update - update route metric based on OGM | |
385 | * @bat_priv: the bat priv with all the soft interface information | |
386 | * @ogm2: OGM2 structure | |
387 | * @orig_node: Originator structure for which the OGM has been received | |
388 | * @neigh_node: the neigh_node through with the OGM has been received | |
389 | * @if_incoming: the interface where this packet was received | |
390 | * @if_outgoing: the interface for which the packet should be considered | |
391 | * | |
392 | * Return: | |
393 | * 1 if the OGM is new, | |
394 | * 0 if it is not new but valid, | |
395 | * <0 on error (e.g. old OGM) | |
396 | */ | |
397 | static int batadv_v_ogm_metric_update(struct batadv_priv *bat_priv, | |
398 | const struct batadv_ogm2_packet *ogm2, | |
399 | struct batadv_orig_node *orig_node, | |
400 | struct batadv_neigh_node *neigh_node, | |
401 | struct batadv_hard_iface *if_incoming, | |
402 | struct batadv_hard_iface *if_outgoing) | |
403 | { | |
404 | struct batadv_orig_ifinfo *orig_ifinfo = NULL; | |
405 | struct batadv_neigh_ifinfo *neigh_ifinfo = NULL; | |
406 | bool protection_started = false; | |
407 | int ret = -EINVAL; | |
408 | u32 path_throughput; | |
409 | s32 seq_diff; | |
410 | ||
411 | orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing); | |
412 | if (!orig_ifinfo) | |
413 | goto out; | |
414 | ||
415 | seq_diff = ntohl(ogm2->seqno) - orig_ifinfo->last_real_seqno; | |
416 | ||
417 | if (!hlist_empty(&orig_node->neigh_list) && | |
418 | batadv_window_protected(bat_priv, seq_diff, | |
419 | BATADV_OGM_MAX_AGE, | |
420 | &orig_ifinfo->batman_seqno_reset, | |
421 | &protection_started)) { | |
422 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
423 | "Drop packet: packet within window protection time from %pM\n", | |
424 | ogm2->orig); | |
425 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
426 | "Last reset: %ld, %ld\n", | |
427 | orig_ifinfo->batman_seqno_reset, jiffies); | |
428 | goto out; | |
429 | } | |
430 | ||
431 | /* drop packets with old seqnos, however accept the first packet after | |
432 | * a host has been rebooted. | |
433 | */ | |
434 | if ((seq_diff < 0) && !protection_started) | |
435 | goto out; | |
436 | ||
437 | neigh_node->last_seen = jiffies; | |
438 | ||
439 | orig_node->last_seen = jiffies; | |
440 | ||
441 | orig_ifinfo->last_real_seqno = ntohl(ogm2->seqno); | |
442 | orig_ifinfo->last_ttl = ogm2->ttl; | |
443 | ||
444 | neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing); | |
445 | if (!neigh_ifinfo) | |
446 | goto out; | |
447 | ||
448 | path_throughput = batadv_v_forward_penalty(bat_priv, if_incoming, | |
449 | if_outgoing, | |
450 | ntohl(ogm2->throughput)); | |
451 | neigh_ifinfo->bat_v.throughput = path_throughput; | |
452 | neigh_ifinfo->bat_v.last_seqno = ntohl(ogm2->seqno); | |
453 | neigh_ifinfo->last_ttl = ogm2->ttl; | |
454 | ||
455 | if (seq_diff > 0 || protection_started) | |
456 | ret = 1; | |
457 | else | |
458 | ret = 0; | |
459 | out: | |
460 | if (orig_ifinfo) | |
461 | batadv_orig_ifinfo_put(orig_ifinfo); | |
462 | if (neigh_ifinfo) | |
463 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
464 | ||
465 | return ret; | |
466 | } | |
467 | ||
468 | /** | |
469 | * batadv_v_ogm_route_update - update routes based on OGM | |
470 | * @bat_priv: the bat priv with all the soft interface information | |
471 | * @ethhdr: the Ethernet header of the OGM2 | |
472 | * @ogm2: OGM2 structure | |
473 | * @orig_node: Originator structure for which the OGM has been received | |
474 | * @neigh_node: the neigh_node through with the OGM has been received | |
475 | * @if_incoming: the interface where this packet was received | |
476 | * @if_outgoing: the interface for which the packet should be considered | |
efcc9d30 SW |
477 | * |
478 | * Return: true if the packet should be forwarded, false otherwise | |
9323158e | 479 | */ |
efcc9d30 | 480 | static bool batadv_v_ogm_route_update(struct batadv_priv *bat_priv, |
9323158e AQ |
481 | const struct ethhdr *ethhdr, |
482 | const struct batadv_ogm2_packet *ogm2, | |
483 | struct batadv_orig_node *orig_node, | |
484 | struct batadv_neigh_node *neigh_node, | |
485 | struct batadv_hard_iface *if_incoming, | |
486 | struct batadv_hard_iface *if_outgoing) | |
487 | { | |
488 | struct batadv_neigh_node *router = NULL; | |
9323158e | 489 | struct batadv_orig_node *orig_neigh_node = NULL; |
9323158e | 490 | struct batadv_neigh_node *orig_neigh_router = NULL; |
86de37c1 SW |
491 | struct batadv_neigh_ifinfo *router_ifinfo = NULL, *neigh_ifinfo = NULL; |
492 | u32 router_throughput, neigh_throughput; | |
493 | u32 router_last_seqno; | |
494 | u32 neigh_last_seqno; | |
495 | s32 neigh_seq_diff; | |
efcc9d30 | 496 | bool forward = false; |
9323158e AQ |
497 | |
498 | orig_neigh_node = batadv_v_ogm_orig_get(bat_priv, ethhdr->h_source); | |
499 | if (!orig_neigh_node) | |
500 | goto out; | |
501 | ||
502 | orig_neigh_router = batadv_orig_router_get(orig_neigh_node, | |
503 | if_outgoing); | |
504 | ||
505 | /* drop packet if sender is not a direct neighbor and if we | |
506 | * don't route towards it | |
507 | */ | |
508 | router = batadv_orig_router_get(orig_node, if_outgoing); | |
509 | if (router && router->orig_node != orig_node && !orig_neigh_router) { | |
510 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
511 | "Drop packet: OGM via unknown neighbor!\n"); | |
512 | goto out; | |
513 | } | |
514 | ||
86de37c1 SW |
515 | /* Mark the OGM to be considered for forwarding, and update routes |
516 | * if needed. | |
517 | */ | |
efcc9d30 | 518 | forward = true; |
86de37c1 SW |
519 | |
520 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
521 | "Searching and updating originator entry of received packet\n"); | |
522 | ||
523 | /* if this neighbor already is our next hop there is nothing | |
524 | * to change | |
525 | */ | |
526 | if (router == neigh_node) | |
527 | goto out; | |
528 | ||
529 | /* don't consider neighbours with worse throughput. | |
530 | * also switch route if this seqno is BATADV_V_MAX_ORIGDIFF newer than | |
531 | * the last received seqno from our best next hop. | |
532 | */ | |
533 | if (router) { | |
534 | router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing); | |
535 | neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing); | |
536 | ||
537 | /* if these are not allocated, something is wrong. */ | |
538 | if (!router_ifinfo || !neigh_ifinfo) | |
539 | goto out; | |
540 | ||
541 | neigh_last_seqno = neigh_ifinfo->bat_v.last_seqno; | |
542 | router_last_seqno = router_ifinfo->bat_v.last_seqno; | |
543 | neigh_seq_diff = neigh_last_seqno - router_last_seqno; | |
544 | router_throughput = router_ifinfo->bat_v.throughput; | |
545 | neigh_throughput = neigh_ifinfo->bat_v.throughput; | |
546 | ||
547 | if ((neigh_seq_diff < BATADV_OGM_MAX_ORIGDIFF) && | |
548 | (router_throughput >= neigh_throughput)) | |
549 | goto out; | |
550 | } | |
551 | ||
552 | batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node); | |
9323158e | 553 | out: |
9323158e AQ |
554 | if (router) |
555 | batadv_neigh_node_put(router); | |
556 | if (orig_neigh_router) | |
557 | batadv_neigh_node_put(orig_neigh_router); | |
558 | if (orig_neigh_node) | |
559 | batadv_orig_node_put(orig_neigh_node); | |
86de37c1 SW |
560 | if (router_ifinfo) |
561 | batadv_neigh_ifinfo_put(router_ifinfo); | |
562 | if (neigh_ifinfo) | |
563 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
efcc9d30 SW |
564 | |
565 | return forward; | |
9323158e AQ |
566 | } |
567 | ||
568 | /** | |
569 | * batadv_v_ogm_process_per_outif - process a batman v OGM for an outgoing if | |
570 | * @bat_priv: the bat priv with all the soft interface information | |
571 | * @ethhdr: the Ethernet header of the OGM2 | |
572 | * @ogm2: OGM2 structure | |
573 | * @orig_node: Originator structure for which the OGM has been received | |
574 | * @neigh_node: the neigh_node through with the OGM has been received | |
575 | * @if_incoming: the interface where this packet was received | |
576 | * @if_outgoing: the interface for which the packet should be considered | |
577 | */ | |
578 | static void | |
579 | batadv_v_ogm_process_per_outif(struct batadv_priv *bat_priv, | |
580 | const struct ethhdr *ethhdr, | |
581 | const struct batadv_ogm2_packet *ogm2, | |
582 | struct batadv_orig_node *orig_node, | |
583 | struct batadv_neigh_node *neigh_node, | |
584 | struct batadv_hard_iface *if_incoming, | |
585 | struct batadv_hard_iface *if_outgoing) | |
586 | { | |
587 | int seqno_age; | |
efcc9d30 | 588 | bool forward; |
9323158e AQ |
589 | |
590 | /* first, update the metric with according sanity checks */ | |
591 | seqno_age = batadv_v_ogm_metric_update(bat_priv, ogm2, orig_node, | |
592 | neigh_node, if_incoming, | |
593 | if_outgoing); | |
594 | ||
595 | /* outdated sequence numbers are to be discarded */ | |
596 | if (seqno_age < 0) | |
597 | return; | |
598 | ||
599 | /* only unknown & newer OGMs contain TVLVs we are interested in */ | |
600 | if ((seqno_age > 0) && (if_outgoing == BATADV_IF_DEFAULT)) | |
601 | batadv_tvlv_containers_process(bat_priv, true, orig_node, | |
602 | NULL, NULL, | |
603 | (unsigned char *)(ogm2 + 1), | |
604 | ntohs(ogm2->tvlv_len)); | |
605 | ||
606 | /* if the metric update went through, update routes if needed */ | |
efcc9d30 SW |
607 | forward = batadv_v_ogm_route_update(bat_priv, ethhdr, ogm2, orig_node, |
608 | neigh_node, if_incoming, | |
609 | if_outgoing); | |
610 | ||
611 | /* if the routes have been processed correctly, check and forward */ | |
612 | if (forward) | |
613 | batadv_v_ogm_forward(bat_priv, ogm2, orig_node, neigh_node, | |
614 | if_incoming, if_outgoing); | |
9323158e AQ |
615 | } |
616 | ||
617 | /** | |
618 | * batadv_v_ogm_aggr_packet - checks if there is another OGM aggregated | |
619 | * @buff_pos: current position in the skb | |
620 | * @packet_len: total length of the skb | |
621 | * @tvlv_len: tvlv length of the previously considered OGM | |
622 | * | |
623 | * Return: true if there is enough space for another OGM, false otherwise. | |
624 | */ | |
625 | static bool batadv_v_ogm_aggr_packet(int buff_pos, int packet_len, | |
626 | __be16 tvlv_len) | |
627 | { | |
628 | int next_buff_pos = 0; | |
629 | ||
630 | next_buff_pos += buff_pos + BATADV_OGM2_HLEN; | |
631 | next_buff_pos += ntohs(tvlv_len); | |
632 | ||
633 | return (next_buff_pos <= packet_len) && | |
634 | (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES); | |
635 | } | |
636 | ||
637 | /** | |
638 | * batadv_v_ogm_process - process an incoming batman v OGM | |
639 | * @skb: the skb containing the OGM | |
640 | * @ogm_offset: offset to the OGM which should be processed (for aggregates) | |
641 | * @if_incoming: the interface where this packet was receved | |
642 | */ | |
643 | static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset, | |
644 | struct batadv_hard_iface *if_incoming) | |
645 | { | |
646 | struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); | |
647 | struct ethhdr *ethhdr; | |
648 | struct batadv_orig_node *orig_node = NULL; | |
649 | struct batadv_hardif_neigh_node *hardif_neigh = NULL; | |
650 | struct batadv_neigh_node *neigh_node = NULL; | |
651 | struct batadv_hard_iface *hard_iface; | |
652 | struct batadv_ogm2_packet *ogm_packet; | |
653 | u32 ogm_throughput, link_throughput, path_throughput; | |
654 | ||
655 | ethhdr = eth_hdr(skb); | |
656 | ogm_packet = (struct batadv_ogm2_packet *)(skb->data + ogm_offset); | |
657 | ||
658 | ogm_throughput = ntohl(ogm_packet->throughput); | |
659 | ||
660 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
661 | "Received OGM2 packet via NB: %pM, IF: %s [%pM] (from OG: %pM, seqno %u, troughput %u, TTL %u, V %u, tvlv_len %u)\n", | |
662 | ethhdr->h_source, if_incoming->net_dev->name, | |
663 | if_incoming->net_dev->dev_addr, ogm_packet->orig, | |
664 | ntohl(ogm_packet->seqno), ogm_throughput, ogm_packet->ttl, | |
665 | ogm_packet->version, ntohs(ogm_packet->tvlv_len)); | |
666 | ||
667 | /* If the troughput metric is 0, immediately drop the packet. No need to | |
668 | * create orig_node / neigh_node for an unusable route. | |
669 | */ | |
670 | if (ogm_throughput == 0) { | |
671 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
672 | "Drop packet: originator packet with troughput metric of 0\n"); | |
673 | return; | |
674 | } | |
675 | ||
676 | /* require ELP packets be to received from this neighbor first */ | |
677 | hardif_neigh = batadv_hardif_neigh_get(if_incoming, ethhdr->h_source); | |
678 | if (!hardif_neigh) { | |
679 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
680 | "Drop packet: OGM via unknown neighbor!\n"); | |
681 | goto out; | |
682 | } | |
683 | ||
684 | orig_node = batadv_v_ogm_orig_get(bat_priv, ogm_packet->orig); | |
685 | if (!orig_node) | |
686 | return; | |
687 | ||
6f0a6b5e ML |
688 | neigh_node = batadv_neigh_node_get_or_create(orig_node, if_incoming, |
689 | ethhdr->h_source); | |
9323158e AQ |
690 | if (!neigh_node) |
691 | goto out; | |
692 | ||
693 | /* Update the received throughput metric to match the link | |
694 | * characteristic: | |
695 | * - If this OGM traveled one hop so far (emitted by single hop | |
696 | * neighbor) the path throughput metric equals the link throughput. | |
697 | * - For OGMs traversing more than hop the path throughput metric is | |
698 | * the smaller of the path throughput and the link throughput. | |
699 | */ | |
700 | link_throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput); | |
701 | path_throughput = min_t(u32, link_throughput, ogm_throughput); | |
702 | ogm_packet->throughput = htonl(path_throughput); | |
703 | ||
704 | batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet, orig_node, | |
705 | neigh_node, if_incoming, | |
706 | BATADV_IF_DEFAULT); | |
707 | ||
708 | rcu_read_lock(); | |
709 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { | |
710 | if (hard_iface->if_status != BATADV_IF_ACTIVE) | |
711 | continue; | |
712 | ||
713 | if (hard_iface->soft_iface != bat_priv->soft_iface) | |
714 | continue; | |
715 | ||
27353446 SE |
716 | if (!kref_get_unless_zero(&hard_iface->refcount)) |
717 | continue; | |
718 | ||
9323158e AQ |
719 | batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet, |
720 | orig_node, neigh_node, | |
721 | if_incoming, hard_iface); | |
27353446 SE |
722 | |
723 | batadv_hardif_put(hard_iface); | |
9323158e AQ |
724 | } |
725 | rcu_read_unlock(); | |
726 | out: | |
727 | if (orig_node) | |
728 | batadv_orig_node_put(orig_node); | |
729 | if (neigh_node) | |
730 | batadv_neigh_node_put(neigh_node); | |
731 | if (hardif_neigh) | |
732 | batadv_hardif_neigh_put(hardif_neigh); | |
733 | } | |
734 | ||
0da00359 AQ |
735 | /** |
736 | * batadv_v_ogm_packet_recv - OGM2 receiving handler | |
737 | * @skb: the received OGM | |
738 | * @if_incoming: the interface where this OGM has been received | |
739 | * | |
740 | * Return: NET_RX_SUCCESS and consume the skb on success or returns NET_RX_DROP | |
741 | * (without freeing the skb) on failure | |
742 | */ | |
743 | int batadv_v_ogm_packet_recv(struct sk_buff *skb, | |
744 | struct batadv_hard_iface *if_incoming) | |
745 | { | |
746 | struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); | |
747 | struct batadv_ogm2_packet *ogm_packet; | |
748 | struct ethhdr *ethhdr = eth_hdr(skb); | |
9323158e AQ |
749 | int ogm_offset; |
750 | u8 *packet_pos; | |
751 | int ret = NET_RX_DROP; | |
0da00359 AQ |
752 | |
753 | /* did we receive a OGM2 packet on an interface that does not have | |
754 | * B.A.T.M.A.N. V enabled ? | |
755 | */ | |
29824a55 | 756 | if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0) |
0da00359 AQ |
757 | return NET_RX_DROP; |
758 | ||
759 | if (!batadv_check_management_packet(skb, if_incoming, BATADV_OGM2_HLEN)) | |
760 | return NET_RX_DROP; | |
761 | ||
762 | if (batadv_is_my_mac(bat_priv, ethhdr->h_source)) | |
763 | return NET_RX_DROP; | |
764 | ||
765 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
766 | ||
767 | if (batadv_is_my_mac(bat_priv, ogm_packet->orig)) | |
768 | return NET_RX_DROP; | |
769 | ||
770 | batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX); | |
771 | batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES, | |
772 | skb->len + ETH_HLEN); | |
773 | ||
9323158e AQ |
774 | ogm_offset = 0; |
775 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
776 | ||
777 | while (batadv_v_ogm_aggr_packet(ogm_offset, skb_headlen(skb), | |
778 | ogm_packet->tvlv_len)) { | |
779 | batadv_v_ogm_process(skb, ogm_offset, if_incoming); | |
780 | ||
781 | ogm_offset += BATADV_OGM2_HLEN; | |
782 | ogm_offset += ntohs(ogm_packet->tvlv_len); | |
783 | ||
784 | packet_pos = skb->data + ogm_offset; | |
785 | ogm_packet = (struct batadv_ogm2_packet *)packet_pos; | |
786 | } | |
787 | ||
788 | ret = NET_RX_SUCCESS; | |
0da00359 | 789 | consume_skb(skb); |
9323158e AQ |
790 | |
791 | return ret; | |
0da00359 AQ |
792 | } |
793 | ||
794 | /** | |
795 | * batadv_v_ogm_init - initialise the OGM2 engine | |
796 | * @bat_priv: the bat priv with all the soft interface information | |
797 | * | |
798 | * Return: 0 on success or a negative error code in case of failure | |
799 | */ | |
800 | int batadv_v_ogm_init(struct batadv_priv *bat_priv) | |
801 | { | |
802 | struct batadv_ogm2_packet *ogm_packet; | |
803 | unsigned char *ogm_buff; | |
804 | u32 random_seqno; | |
805 | ||
806 | bat_priv->bat_v.ogm_buff_len = BATADV_OGM2_HLEN; | |
807 | ogm_buff = kzalloc(bat_priv->bat_v.ogm_buff_len, GFP_ATOMIC); | |
808 | if (!ogm_buff) | |
809 | return -ENOMEM; | |
810 | ||
811 | bat_priv->bat_v.ogm_buff = ogm_buff; | |
812 | ogm_packet = (struct batadv_ogm2_packet *)ogm_buff; | |
813 | ogm_packet->packet_type = BATADV_OGM2; | |
814 | ogm_packet->version = BATADV_COMPAT_VERSION; | |
815 | ogm_packet->ttl = BATADV_TTL; | |
816 | ogm_packet->flags = BATADV_NO_FLAGS; | |
817 | ogm_packet->throughput = htonl(BATADV_THROUGHPUT_MAX_VALUE); | |
818 | ||
819 | /* randomize initial seqno to avoid collision */ | |
820 | get_random_bytes(&random_seqno, sizeof(random_seqno)); | |
821 | atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno); | |
822 | INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send); | |
823 | ||
824 | return 0; | |
825 | } | |
826 | ||
827 | /** | |
828 | * batadv_v_ogm_free - free OGM private resources | |
829 | * @bat_priv: the bat priv with all the soft interface information | |
830 | */ | |
831 | void batadv_v_ogm_free(struct batadv_priv *bat_priv) | |
832 | { | |
833 | cancel_delayed_work_sync(&bat_priv->bat_v.ogm_wq); | |
834 | ||
835 | kfree(bat_priv->bat_v.ogm_buff); | |
836 | bat_priv->bat_v.ogm_buff = NULL; | |
837 | bat_priv->bat_v.ogm_buff_len = 0; | |
838 | } |