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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 | ||
42 | #include "hard-interface.h" | |
9323158e AQ |
43 | #include "hash.h" |
44 | #include "originator.h" | |
0da00359 AQ |
45 | #include "packet.h" |
46 | #include "routing.h" | |
47 | #include "send.h" | |
48 | #include "translation-table.h" | |
1f8dce49 | 49 | #include "tvlv.h" |
0da00359 | 50 | |
9323158e AQ |
51 | /** |
52 | * batadv_v_ogm_orig_get - retrieve and possibly create an originator node | |
53 | * @bat_priv: the bat priv with all the soft interface information | |
54 | * @addr: the address of the originator | |
55 | * | |
56 | * Return: the orig_node corresponding to the specified address. If such object | |
57 | * does not exist it is allocated here. In case of allocation failure returns | |
58 | * NULL. | |
59 | */ | |
60 | struct batadv_orig_node *batadv_v_ogm_orig_get(struct batadv_priv *bat_priv, | |
61 | const u8 *addr) | |
62 | { | |
63 | struct batadv_orig_node *orig_node; | |
64 | int hash_added; | |
65 | ||
66 | orig_node = batadv_orig_hash_find(bat_priv, addr); | |
67 | if (orig_node) | |
68 | return orig_node; | |
69 | ||
70 | orig_node = batadv_orig_node_new(bat_priv, addr); | |
71 | if (!orig_node) | |
72 | return NULL; | |
73 | ||
74 | hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig, | |
75 | batadv_choose_orig, orig_node, | |
76 | &orig_node->hash_entry); | |
77 | if (hash_added != 0) { | |
78 | /* orig_node->refcounter is initialised to 2 by | |
79 | * batadv_orig_node_new() | |
80 | */ | |
81 | batadv_orig_node_put(orig_node); | |
82 | batadv_orig_node_put(orig_node); | |
83 | orig_node = NULL; | |
84 | } | |
85 | ||
86 | return orig_node; | |
87 | } | |
88 | ||
0da00359 AQ |
89 | /** |
90 | * batadv_v_ogm_start_timer - restart the OGM sending timer | |
91 | * @bat_priv: the bat priv with all the soft interface information | |
92 | */ | |
93 | static void batadv_v_ogm_start_timer(struct batadv_priv *bat_priv) | |
94 | { | |
95 | unsigned long msecs; | |
96 | /* this function may be invoked in different contexts (ogm rescheduling | |
97 | * or hard_iface activation), but the work timer should not be reset | |
98 | */ | |
99 | if (delayed_work_pending(&bat_priv->bat_v.ogm_wq)) | |
100 | return; | |
101 | ||
102 | msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; | |
103 | msecs += prandom_u32() % (2 * BATADV_JITTER); | |
104 | queue_delayed_work(batadv_event_workqueue, &bat_priv->bat_v.ogm_wq, | |
105 | msecs_to_jiffies(msecs)); | |
106 | } | |
107 | ||
108 | /** | |
109 | * batadv_v_ogm_send_to_if - send a batman ogm using a given interface | |
110 | * @skb: the OGM to send | |
111 | * @hard_iface: the interface to use to send the OGM | |
112 | */ | |
113 | static void batadv_v_ogm_send_to_if(struct sk_buff *skb, | |
114 | struct batadv_hard_iface *hard_iface) | |
115 | { | |
116 | struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); | |
117 | ||
118 | if (hard_iface->if_status != BATADV_IF_ACTIVE) | |
119 | return; | |
120 | ||
121 | batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX); | |
122 | batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES, | |
123 | skb->len + ETH_HLEN); | |
124 | ||
95d39278 | 125 | batadv_send_broadcast_skb(skb, hard_iface); |
0da00359 AQ |
126 | } |
127 | ||
128 | /** | |
129 | * batadv_v_ogm_send - periodic worker broadcasting the own OGM | |
130 | * @work: work queue item | |
131 | */ | |
132 | static void batadv_v_ogm_send(struct work_struct *work) | |
133 | { | |
134 | struct batadv_hard_iface *hard_iface; | |
135 | struct batadv_priv_bat_v *bat_v; | |
136 | struct batadv_priv *bat_priv; | |
137 | struct batadv_ogm2_packet *ogm_packet; | |
138 | struct sk_buff *skb, *skb_tmp; | |
139 | unsigned char *ogm_buff, *pkt_buff; | |
140 | int ogm_buff_len; | |
141 | u16 tvlv_len = 0; | |
142 | ||
143 | bat_v = container_of(work, struct batadv_priv_bat_v, ogm_wq.work); | |
144 | bat_priv = container_of(bat_v, struct batadv_priv, bat_v); | |
145 | ||
146 | if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) | |
147 | goto out; | |
148 | ||
149 | ogm_buff = bat_priv->bat_v.ogm_buff; | |
150 | ogm_buff_len = bat_priv->bat_v.ogm_buff_len; | |
151 | /* tt changes have to be committed before the tvlv data is | |
152 | * appended as it may alter the tt tvlv container | |
153 | */ | |
154 | batadv_tt_local_commit_changes(bat_priv); | |
155 | tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, &ogm_buff, | |
156 | &ogm_buff_len, | |
157 | BATADV_OGM2_HLEN); | |
158 | ||
159 | bat_priv->bat_v.ogm_buff = ogm_buff; | |
160 | bat_priv->bat_v.ogm_buff_len = ogm_buff_len; | |
161 | ||
162 | skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + ogm_buff_len); | |
163 | if (!skb) | |
164 | goto reschedule; | |
165 | ||
166 | skb_reserve(skb, ETH_HLEN); | |
167 | pkt_buff = skb_put(skb, ogm_buff_len); | |
168 | memcpy(pkt_buff, ogm_buff, ogm_buff_len); | |
169 | ||
170 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
171 | ogm_packet->seqno = htonl(atomic_read(&bat_priv->bat_v.ogm_seqno)); | |
172 | atomic_inc(&bat_priv->bat_v.ogm_seqno); | |
173 | ogm_packet->tvlv_len = htons(tvlv_len); | |
174 | ||
175 | /* broadcast on every interface */ | |
176 | rcu_read_lock(); | |
177 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { | |
178 | if (hard_iface->soft_iface != bat_priv->soft_iface) | |
179 | continue; | |
180 | ||
27353446 SE |
181 | if (!kref_get_unless_zero(&hard_iface->refcount)) |
182 | continue; | |
183 | ||
0da00359 AQ |
184 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, |
185 | "Sending own OGM2 packet (originator %pM, seqno %u, throughput %u, TTL %d) on interface %s [%pM]\n", | |
186 | ogm_packet->orig, ntohl(ogm_packet->seqno), | |
187 | ntohl(ogm_packet->throughput), ogm_packet->ttl, | |
188 | hard_iface->net_dev->name, | |
189 | hard_iface->net_dev->dev_addr); | |
190 | ||
191 | /* this skb gets consumed by batadv_v_ogm_send_to_if() */ | |
192 | skb_tmp = skb_clone(skb, GFP_ATOMIC); | |
27353446 SE |
193 | if (!skb_tmp) { |
194 | batadv_hardif_put(hard_iface); | |
0da00359 | 195 | break; |
27353446 | 196 | } |
0da00359 AQ |
197 | |
198 | batadv_v_ogm_send_to_if(skb_tmp, hard_iface); | |
27353446 | 199 | batadv_hardif_put(hard_iface); |
0da00359 AQ |
200 | } |
201 | rcu_read_unlock(); | |
202 | ||
203 | consume_skb(skb); | |
204 | ||
205 | reschedule: | |
206 | batadv_v_ogm_start_timer(bat_priv); | |
207 | out: | |
208 | return; | |
209 | } | |
210 | ||
211 | /** | |
212 | * batadv_v_ogm_iface_enable - prepare an interface for B.A.T.M.A.N. V | |
213 | * @hard_iface: the interface to prepare | |
214 | * | |
215 | * Takes care of scheduling own OGM sending routine for this interface. | |
216 | * | |
217 | * Return: 0 on success or a negative error code otherwise | |
218 | */ | |
219 | int batadv_v_ogm_iface_enable(struct batadv_hard_iface *hard_iface) | |
220 | { | |
221 | struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); | |
222 | ||
223 | batadv_v_ogm_start_timer(bat_priv); | |
224 | ||
225 | return 0; | |
226 | } | |
227 | ||
228 | /** | |
229 | * batadv_v_ogm_primary_iface_set - set a new primary interface | |
230 | * @primary_iface: the new primary interface | |
231 | */ | |
232 | void batadv_v_ogm_primary_iface_set(struct batadv_hard_iface *primary_iface) | |
233 | { | |
234 | struct batadv_priv *bat_priv = netdev_priv(primary_iface->soft_iface); | |
235 | struct batadv_ogm2_packet *ogm_packet; | |
236 | ||
237 | if (!bat_priv->bat_v.ogm_buff) | |
238 | return; | |
239 | ||
240 | ogm_packet = (struct batadv_ogm2_packet *)bat_priv->bat_v.ogm_buff; | |
241 | ether_addr_copy(ogm_packet->orig, primary_iface->net_dev->dev_addr); | |
242 | } | |
243 | ||
9323158e AQ |
244 | /** |
245 | * batadv_v_forward_penalty - apply a penalty to the throughput metric forwarded | |
246 | * with B.A.T.M.A.N. V OGMs | |
247 | * @bat_priv: the bat priv with all the soft interface information | |
248 | * @if_incoming: the interface where the OGM has been received | |
249 | * @if_outgoing: the interface where the OGM has to be forwarded to | |
250 | * @throughput: the current throughput | |
251 | * | |
252 | * Apply a penalty on the current throughput metric value based on the | |
253 | * characteristic of the interface where the OGM has been received. The return | |
254 | * value is computed as follows: | |
255 | * - throughput * 50% if the incoming and outgoing interface are the | |
256 | * same WiFi interface and the throughput is above | |
257 | * 1MBit/s | |
258 | * - throughput if the outgoing interface is the default | |
259 | * interface (i.e. this OGM is processed for the | |
260 | * internal table and not forwarded) | |
261 | * - throughput * hop penalty otherwise | |
262 | * | |
263 | * Return: the penalised throughput metric. | |
264 | */ | |
265 | static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv, | |
266 | struct batadv_hard_iface *if_incoming, | |
267 | struct batadv_hard_iface *if_outgoing, | |
268 | u32 throughput) | |
269 | { | |
270 | int hop_penalty = atomic_read(&bat_priv->hop_penalty); | |
271 | int hop_penalty_max = BATADV_TQ_MAX_VALUE; | |
272 | ||
273 | /* Don't apply hop penalty in default originator table. */ | |
274 | if (if_outgoing == BATADV_IF_DEFAULT) | |
275 | return throughput; | |
276 | ||
277 | /* Forwarding on the same WiFi interface cuts the throughput in half | |
278 | * due to the store & forward characteristics of WIFI. | |
279 | * Very low throughput values are the exception. | |
280 | */ | |
281 | if ((throughput > 10) && | |
282 | (if_incoming == if_outgoing) && | |
c833484e | 283 | !(if_incoming->bat_v.flags & BATADV_FULL_DUPLEX)) |
9323158e AQ |
284 | return throughput / 2; |
285 | ||
286 | /* hop penalty of 255 equals 100% */ | |
287 | return throughput * (hop_penalty_max - hop_penalty) / hop_penalty_max; | |
288 | } | |
289 | ||
290 | /** | |
efcc9d30 SW |
291 | * batadv_v_ogm_forward - check conditions and forward an OGM to the given |
292 | * outgoing interface | |
9323158e AQ |
293 | * @bat_priv: the bat priv with all the soft interface information |
294 | * @ogm_received: previously received OGM to be forwarded | |
efcc9d30 SW |
295 | * @orig_node: the originator which has been updated |
296 | * @neigh_node: the neigh_node through with the OGM has been received | |
9323158e AQ |
297 | * @if_incoming: the interface on which this OGM was received on |
298 | * @if_outgoing: the interface to which the OGM has to be forwarded to | |
299 | * | |
300 | * Forward an OGM to an interface after having altered the throughput metric and | |
301 | * the TTL value contained in it. The original OGM isn't modified. | |
302 | */ | |
303 | static void batadv_v_ogm_forward(struct batadv_priv *bat_priv, | |
304 | const struct batadv_ogm2_packet *ogm_received, | |
efcc9d30 SW |
305 | struct batadv_orig_node *orig_node, |
306 | struct batadv_neigh_node *neigh_node, | |
9323158e AQ |
307 | struct batadv_hard_iface *if_incoming, |
308 | struct batadv_hard_iface *if_outgoing) | |
309 | { | |
efcc9d30 SW |
310 | struct batadv_neigh_ifinfo *neigh_ifinfo = NULL; |
311 | struct batadv_orig_ifinfo *orig_ifinfo = NULL; | |
312 | struct batadv_neigh_node *router = NULL; | |
9323158e AQ |
313 | struct batadv_ogm2_packet *ogm_forward; |
314 | unsigned char *skb_buff; | |
315 | struct sk_buff *skb; | |
316 | size_t packet_len; | |
317 | u16 tvlv_len; | |
318 | ||
efcc9d30 SW |
319 | /* only forward for specific interfaces, not for the default one. */ |
320 | if (if_outgoing == BATADV_IF_DEFAULT) | |
321 | goto out; | |
322 | ||
323 | orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing); | |
324 | if (!orig_ifinfo) | |
325 | goto out; | |
326 | ||
327 | /* acquire possibly updated router */ | |
328 | router = batadv_orig_router_get(orig_node, if_outgoing); | |
329 | ||
330 | /* strict rule: forward packets coming from the best next hop only */ | |
331 | if (neigh_node != router) | |
332 | goto out; | |
333 | ||
334 | /* don't forward the same seqno twice on one interface */ | |
335 | if (orig_ifinfo->last_seqno_forwarded == ntohl(ogm_received->seqno)) | |
336 | goto out; | |
337 | ||
338 | orig_ifinfo->last_seqno_forwarded = ntohl(ogm_received->seqno); | |
339 | ||
9323158e AQ |
340 | if (ogm_received->ttl <= 1) { |
341 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n"); | |
efcc9d30 | 342 | goto out; |
9323158e AQ |
343 | } |
344 | ||
efcc9d30 SW |
345 | neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing); |
346 | if (!neigh_ifinfo) | |
347 | goto out; | |
348 | ||
9323158e AQ |
349 | tvlv_len = ntohs(ogm_received->tvlv_len); |
350 | ||
351 | packet_len = BATADV_OGM2_HLEN + tvlv_len; | |
352 | skb = netdev_alloc_skb_ip_align(if_outgoing->net_dev, | |
353 | ETH_HLEN + packet_len); | |
354 | if (!skb) | |
efcc9d30 | 355 | goto out; |
9323158e AQ |
356 | |
357 | skb_reserve(skb, ETH_HLEN); | |
358 | skb_buff = skb_put(skb, packet_len); | |
359 | memcpy(skb_buff, ogm_received, packet_len); | |
360 | ||
361 | /* apply forward penalty */ | |
362 | ogm_forward = (struct batadv_ogm2_packet *)skb_buff; | |
efcc9d30 | 363 | ogm_forward->throughput = htonl(neigh_ifinfo->bat_v.throughput); |
9323158e AQ |
364 | ogm_forward->ttl--; |
365 | ||
366 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
367 | "Forwarding OGM2 packet on %s: throughput %u, ttl %u, received via %s\n", | |
efcc9d30 SW |
368 | if_outgoing->net_dev->name, ntohl(ogm_forward->throughput), |
369 | ogm_forward->ttl, if_incoming->net_dev->name); | |
9323158e AQ |
370 | |
371 | batadv_v_ogm_send_to_if(skb, if_outgoing); | |
efcc9d30 SW |
372 | |
373 | out: | |
374 | if (orig_ifinfo) | |
375 | batadv_orig_ifinfo_put(orig_ifinfo); | |
376 | if (router) | |
377 | batadv_neigh_node_put(router); | |
378 | if (neigh_ifinfo) | |
379 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
9323158e AQ |
380 | } |
381 | ||
382 | /** | |
383 | * batadv_v_ogm_metric_update - update route metric based on OGM | |
384 | * @bat_priv: the bat priv with all the soft interface information | |
385 | * @ogm2: OGM2 structure | |
386 | * @orig_node: Originator structure for which the OGM has been received | |
387 | * @neigh_node: the neigh_node through with the OGM has been received | |
388 | * @if_incoming: the interface where this packet was received | |
389 | * @if_outgoing: the interface for which the packet should be considered | |
390 | * | |
391 | * Return: | |
392 | * 1 if the OGM is new, | |
393 | * 0 if it is not new but valid, | |
394 | * <0 on error (e.g. old OGM) | |
395 | */ | |
396 | static int batadv_v_ogm_metric_update(struct batadv_priv *bat_priv, | |
397 | const struct batadv_ogm2_packet *ogm2, | |
398 | struct batadv_orig_node *orig_node, | |
399 | struct batadv_neigh_node *neigh_node, | |
400 | struct batadv_hard_iface *if_incoming, | |
401 | struct batadv_hard_iface *if_outgoing) | |
402 | { | |
403 | struct batadv_orig_ifinfo *orig_ifinfo = NULL; | |
404 | struct batadv_neigh_ifinfo *neigh_ifinfo = NULL; | |
405 | bool protection_started = false; | |
406 | int ret = -EINVAL; | |
407 | u32 path_throughput; | |
408 | s32 seq_diff; | |
409 | ||
410 | orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing); | |
411 | if (!orig_ifinfo) | |
412 | goto out; | |
413 | ||
414 | seq_diff = ntohl(ogm2->seqno) - orig_ifinfo->last_real_seqno; | |
415 | ||
416 | if (!hlist_empty(&orig_node->neigh_list) && | |
417 | batadv_window_protected(bat_priv, seq_diff, | |
418 | BATADV_OGM_MAX_AGE, | |
419 | &orig_ifinfo->batman_seqno_reset, | |
420 | &protection_started)) { | |
421 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
422 | "Drop packet: packet within window protection time from %pM\n", | |
423 | ogm2->orig); | |
424 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
425 | "Last reset: %ld, %ld\n", | |
426 | orig_ifinfo->batman_seqno_reset, jiffies); | |
427 | goto out; | |
428 | } | |
429 | ||
430 | /* drop packets with old seqnos, however accept the first packet after | |
431 | * a host has been rebooted. | |
432 | */ | |
433 | if ((seq_diff < 0) && !protection_started) | |
434 | goto out; | |
435 | ||
436 | neigh_node->last_seen = jiffies; | |
437 | ||
438 | orig_node->last_seen = jiffies; | |
439 | ||
440 | orig_ifinfo->last_real_seqno = ntohl(ogm2->seqno); | |
441 | orig_ifinfo->last_ttl = ogm2->ttl; | |
442 | ||
443 | neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing); | |
444 | if (!neigh_ifinfo) | |
445 | goto out; | |
446 | ||
447 | path_throughput = batadv_v_forward_penalty(bat_priv, if_incoming, | |
448 | if_outgoing, | |
449 | ntohl(ogm2->throughput)); | |
450 | neigh_ifinfo->bat_v.throughput = path_throughput; | |
451 | neigh_ifinfo->bat_v.last_seqno = ntohl(ogm2->seqno); | |
452 | neigh_ifinfo->last_ttl = ogm2->ttl; | |
453 | ||
454 | if (seq_diff > 0 || protection_started) | |
455 | ret = 1; | |
456 | else | |
457 | ret = 0; | |
458 | out: | |
459 | if (orig_ifinfo) | |
460 | batadv_orig_ifinfo_put(orig_ifinfo); | |
461 | if (neigh_ifinfo) | |
462 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
463 | ||
464 | return ret; | |
465 | } | |
466 | ||
467 | /** | |
468 | * batadv_v_ogm_route_update - update routes based on OGM | |
469 | * @bat_priv: the bat priv with all the soft interface information | |
470 | * @ethhdr: the Ethernet header of the OGM2 | |
471 | * @ogm2: OGM2 structure | |
472 | * @orig_node: Originator structure for which the OGM has been received | |
473 | * @neigh_node: the neigh_node through with the OGM has been received | |
474 | * @if_incoming: the interface where this packet was received | |
475 | * @if_outgoing: the interface for which the packet should be considered | |
efcc9d30 SW |
476 | * |
477 | * Return: true if the packet should be forwarded, false otherwise | |
9323158e | 478 | */ |
efcc9d30 | 479 | static bool batadv_v_ogm_route_update(struct batadv_priv *bat_priv, |
9323158e AQ |
480 | const struct ethhdr *ethhdr, |
481 | const struct batadv_ogm2_packet *ogm2, | |
482 | struct batadv_orig_node *orig_node, | |
483 | struct batadv_neigh_node *neigh_node, | |
484 | struct batadv_hard_iface *if_incoming, | |
485 | struct batadv_hard_iface *if_outgoing) | |
486 | { | |
487 | struct batadv_neigh_node *router = NULL; | |
9323158e | 488 | struct batadv_orig_node *orig_neigh_node = NULL; |
9323158e | 489 | struct batadv_neigh_node *orig_neigh_router = NULL; |
86de37c1 SW |
490 | struct batadv_neigh_ifinfo *router_ifinfo = NULL, *neigh_ifinfo = NULL; |
491 | u32 router_throughput, neigh_throughput; | |
492 | u32 router_last_seqno; | |
493 | u32 neigh_last_seqno; | |
494 | s32 neigh_seq_diff; | |
efcc9d30 | 495 | bool forward = false; |
9323158e AQ |
496 | |
497 | orig_neigh_node = batadv_v_ogm_orig_get(bat_priv, ethhdr->h_source); | |
498 | if (!orig_neigh_node) | |
499 | goto out; | |
500 | ||
501 | orig_neigh_router = batadv_orig_router_get(orig_neigh_node, | |
502 | if_outgoing); | |
503 | ||
504 | /* drop packet if sender is not a direct neighbor and if we | |
505 | * don't route towards it | |
506 | */ | |
507 | router = batadv_orig_router_get(orig_node, if_outgoing); | |
508 | if (router && router->orig_node != orig_node && !orig_neigh_router) { | |
509 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
510 | "Drop packet: OGM via unknown neighbor!\n"); | |
511 | goto out; | |
512 | } | |
513 | ||
86de37c1 SW |
514 | /* Mark the OGM to be considered for forwarding, and update routes |
515 | * if needed. | |
516 | */ | |
efcc9d30 | 517 | forward = true; |
86de37c1 SW |
518 | |
519 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
520 | "Searching and updating originator entry of received packet\n"); | |
521 | ||
522 | /* if this neighbor already is our next hop there is nothing | |
523 | * to change | |
524 | */ | |
525 | if (router == neigh_node) | |
526 | goto out; | |
527 | ||
528 | /* don't consider neighbours with worse throughput. | |
529 | * also switch route if this seqno is BATADV_V_MAX_ORIGDIFF newer than | |
530 | * the last received seqno from our best next hop. | |
531 | */ | |
532 | if (router) { | |
533 | router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing); | |
534 | neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing); | |
535 | ||
536 | /* if these are not allocated, something is wrong. */ | |
537 | if (!router_ifinfo || !neigh_ifinfo) | |
538 | goto out; | |
539 | ||
540 | neigh_last_seqno = neigh_ifinfo->bat_v.last_seqno; | |
541 | router_last_seqno = router_ifinfo->bat_v.last_seqno; | |
542 | neigh_seq_diff = neigh_last_seqno - router_last_seqno; | |
543 | router_throughput = router_ifinfo->bat_v.throughput; | |
544 | neigh_throughput = neigh_ifinfo->bat_v.throughput; | |
545 | ||
546 | if ((neigh_seq_diff < BATADV_OGM_MAX_ORIGDIFF) && | |
547 | (router_throughput >= neigh_throughput)) | |
548 | goto out; | |
549 | } | |
550 | ||
551 | batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node); | |
9323158e | 552 | out: |
9323158e AQ |
553 | if (router) |
554 | batadv_neigh_node_put(router); | |
555 | if (orig_neigh_router) | |
556 | batadv_neigh_node_put(orig_neigh_router); | |
557 | if (orig_neigh_node) | |
558 | batadv_orig_node_put(orig_neigh_node); | |
86de37c1 SW |
559 | if (router_ifinfo) |
560 | batadv_neigh_ifinfo_put(router_ifinfo); | |
561 | if (neigh_ifinfo) | |
562 | batadv_neigh_ifinfo_put(neigh_ifinfo); | |
efcc9d30 SW |
563 | |
564 | return forward; | |
9323158e AQ |
565 | } |
566 | ||
567 | /** | |
568 | * batadv_v_ogm_process_per_outif - process a batman v OGM for an outgoing if | |
569 | * @bat_priv: the bat priv with all the soft interface information | |
570 | * @ethhdr: the Ethernet header of the OGM2 | |
571 | * @ogm2: OGM2 structure | |
572 | * @orig_node: Originator structure for which the OGM has been received | |
573 | * @neigh_node: the neigh_node through with the OGM has been received | |
574 | * @if_incoming: the interface where this packet was received | |
575 | * @if_outgoing: the interface for which the packet should be considered | |
576 | */ | |
577 | static void | |
578 | batadv_v_ogm_process_per_outif(struct batadv_priv *bat_priv, | |
579 | const struct ethhdr *ethhdr, | |
580 | const struct batadv_ogm2_packet *ogm2, | |
581 | struct batadv_orig_node *orig_node, | |
582 | struct batadv_neigh_node *neigh_node, | |
583 | struct batadv_hard_iface *if_incoming, | |
584 | struct batadv_hard_iface *if_outgoing) | |
585 | { | |
586 | int seqno_age; | |
efcc9d30 | 587 | bool forward; |
9323158e AQ |
588 | |
589 | /* first, update the metric with according sanity checks */ | |
590 | seqno_age = batadv_v_ogm_metric_update(bat_priv, ogm2, orig_node, | |
591 | neigh_node, if_incoming, | |
592 | if_outgoing); | |
593 | ||
594 | /* outdated sequence numbers are to be discarded */ | |
595 | if (seqno_age < 0) | |
596 | return; | |
597 | ||
598 | /* only unknown & newer OGMs contain TVLVs we are interested in */ | |
599 | if ((seqno_age > 0) && (if_outgoing == BATADV_IF_DEFAULT)) | |
600 | batadv_tvlv_containers_process(bat_priv, true, orig_node, | |
601 | NULL, NULL, | |
602 | (unsigned char *)(ogm2 + 1), | |
603 | ntohs(ogm2->tvlv_len)); | |
604 | ||
605 | /* if the metric update went through, update routes if needed */ | |
efcc9d30 SW |
606 | forward = batadv_v_ogm_route_update(bat_priv, ethhdr, ogm2, orig_node, |
607 | neigh_node, if_incoming, | |
608 | if_outgoing); | |
609 | ||
610 | /* if the routes have been processed correctly, check and forward */ | |
611 | if (forward) | |
612 | batadv_v_ogm_forward(bat_priv, ogm2, orig_node, neigh_node, | |
613 | if_incoming, if_outgoing); | |
9323158e AQ |
614 | } |
615 | ||
616 | /** | |
617 | * batadv_v_ogm_aggr_packet - checks if there is another OGM aggregated | |
618 | * @buff_pos: current position in the skb | |
619 | * @packet_len: total length of the skb | |
620 | * @tvlv_len: tvlv length of the previously considered OGM | |
621 | * | |
622 | * Return: true if there is enough space for another OGM, false otherwise. | |
623 | */ | |
624 | static bool batadv_v_ogm_aggr_packet(int buff_pos, int packet_len, | |
625 | __be16 tvlv_len) | |
626 | { | |
627 | int next_buff_pos = 0; | |
628 | ||
629 | next_buff_pos += buff_pos + BATADV_OGM2_HLEN; | |
630 | next_buff_pos += ntohs(tvlv_len); | |
631 | ||
632 | return (next_buff_pos <= packet_len) && | |
633 | (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES); | |
634 | } | |
635 | ||
636 | /** | |
637 | * batadv_v_ogm_process - process an incoming batman v OGM | |
638 | * @skb: the skb containing the OGM | |
639 | * @ogm_offset: offset to the OGM which should be processed (for aggregates) | |
640 | * @if_incoming: the interface where this packet was receved | |
641 | */ | |
642 | static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset, | |
643 | struct batadv_hard_iface *if_incoming) | |
644 | { | |
645 | struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); | |
646 | struct ethhdr *ethhdr; | |
647 | struct batadv_orig_node *orig_node = NULL; | |
648 | struct batadv_hardif_neigh_node *hardif_neigh = NULL; | |
649 | struct batadv_neigh_node *neigh_node = NULL; | |
650 | struct batadv_hard_iface *hard_iface; | |
651 | struct batadv_ogm2_packet *ogm_packet; | |
652 | u32 ogm_throughput, link_throughput, path_throughput; | |
653 | ||
654 | ethhdr = eth_hdr(skb); | |
655 | ogm_packet = (struct batadv_ogm2_packet *)(skb->data + ogm_offset); | |
656 | ||
657 | ogm_throughput = ntohl(ogm_packet->throughput); | |
658 | ||
659 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
660 | "Received OGM2 packet via NB: %pM, IF: %s [%pM] (from OG: %pM, seqno %u, troughput %u, TTL %u, V %u, tvlv_len %u)\n", | |
661 | ethhdr->h_source, if_incoming->net_dev->name, | |
662 | if_incoming->net_dev->dev_addr, ogm_packet->orig, | |
663 | ntohl(ogm_packet->seqno), ogm_throughput, ogm_packet->ttl, | |
664 | ogm_packet->version, ntohs(ogm_packet->tvlv_len)); | |
665 | ||
666 | /* If the troughput metric is 0, immediately drop the packet. No need to | |
667 | * create orig_node / neigh_node for an unusable route. | |
668 | */ | |
669 | if (ogm_throughput == 0) { | |
670 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
671 | "Drop packet: originator packet with troughput metric of 0\n"); | |
672 | return; | |
673 | } | |
674 | ||
675 | /* require ELP packets be to received from this neighbor first */ | |
676 | hardif_neigh = batadv_hardif_neigh_get(if_incoming, ethhdr->h_source); | |
677 | if (!hardif_neigh) { | |
678 | batadv_dbg(BATADV_DBG_BATMAN, bat_priv, | |
679 | "Drop packet: OGM via unknown neighbor!\n"); | |
680 | goto out; | |
681 | } | |
682 | ||
683 | orig_node = batadv_v_ogm_orig_get(bat_priv, ogm_packet->orig); | |
684 | if (!orig_node) | |
685 | return; | |
686 | ||
6f0a6b5e ML |
687 | neigh_node = batadv_neigh_node_get_or_create(orig_node, if_incoming, |
688 | ethhdr->h_source); | |
9323158e AQ |
689 | if (!neigh_node) |
690 | goto out; | |
691 | ||
692 | /* Update the received throughput metric to match the link | |
693 | * characteristic: | |
694 | * - If this OGM traveled one hop so far (emitted by single hop | |
695 | * neighbor) the path throughput metric equals the link throughput. | |
696 | * - For OGMs traversing more than hop the path throughput metric is | |
697 | * the smaller of the path throughput and the link throughput. | |
698 | */ | |
699 | link_throughput = ewma_throughput_read(&hardif_neigh->bat_v.throughput); | |
700 | path_throughput = min_t(u32, link_throughput, ogm_throughput); | |
701 | ogm_packet->throughput = htonl(path_throughput); | |
702 | ||
703 | batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet, orig_node, | |
704 | neigh_node, if_incoming, | |
705 | BATADV_IF_DEFAULT); | |
706 | ||
707 | rcu_read_lock(); | |
708 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { | |
709 | if (hard_iface->if_status != BATADV_IF_ACTIVE) | |
710 | continue; | |
711 | ||
712 | if (hard_iface->soft_iface != bat_priv->soft_iface) | |
713 | continue; | |
714 | ||
27353446 SE |
715 | if (!kref_get_unless_zero(&hard_iface->refcount)) |
716 | continue; | |
717 | ||
9323158e AQ |
718 | batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet, |
719 | orig_node, neigh_node, | |
720 | if_incoming, hard_iface); | |
27353446 SE |
721 | |
722 | batadv_hardif_put(hard_iface); | |
9323158e AQ |
723 | } |
724 | rcu_read_unlock(); | |
725 | out: | |
726 | if (orig_node) | |
727 | batadv_orig_node_put(orig_node); | |
728 | if (neigh_node) | |
729 | batadv_neigh_node_put(neigh_node); | |
730 | if (hardif_neigh) | |
731 | batadv_hardif_neigh_put(hardif_neigh); | |
732 | } | |
733 | ||
0da00359 AQ |
734 | /** |
735 | * batadv_v_ogm_packet_recv - OGM2 receiving handler | |
736 | * @skb: the received OGM | |
737 | * @if_incoming: the interface where this OGM has been received | |
738 | * | |
739 | * Return: NET_RX_SUCCESS and consume the skb on success or returns NET_RX_DROP | |
740 | * (without freeing the skb) on failure | |
741 | */ | |
742 | int batadv_v_ogm_packet_recv(struct sk_buff *skb, | |
743 | struct batadv_hard_iface *if_incoming) | |
744 | { | |
745 | struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface); | |
746 | struct batadv_ogm2_packet *ogm_packet; | |
747 | struct ethhdr *ethhdr = eth_hdr(skb); | |
9323158e AQ |
748 | int ogm_offset; |
749 | u8 *packet_pos; | |
750 | int ret = NET_RX_DROP; | |
0da00359 AQ |
751 | |
752 | /* did we receive a OGM2 packet on an interface that does not have | |
753 | * B.A.T.M.A.N. V enabled ? | |
754 | */ | |
755 | if (strcmp(bat_priv->bat_algo_ops->name, "BATMAN_V") != 0) | |
756 | return NET_RX_DROP; | |
757 | ||
758 | if (!batadv_check_management_packet(skb, if_incoming, BATADV_OGM2_HLEN)) | |
759 | return NET_RX_DROP; | |
760 | ||
761 | if (batadv_is_my_mac(bat_priv, ethhdr->h_source)) | |
762 | return NET_RX_DROP; | |
763 | ||
764 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
765 | ||
766 | if (batadv_is_my_mac(bat_priv, ogm_packet->orig)) | |
767 | return NET_RX_DROP; | |
768 | ||
769 | batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX); | |
770 | batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES, | |
771 | skb->len + ETH_HLEN); | |
772 | ||
9323158e AQ |
773 | ogm_offset = 0; |
774 | ogm_packet = (struct batadv_ogm2_packet *)skb->data; | |
775 | ||
776 | while (batadv_v_ogm_aggr_packet(ogm_offset, skb_headlen(skb), | |
777 | ogm_packet->tvlv_len)) { | |
778 | batadv_v_ogm_process(skb, ogm_offset, if_incoming); | |
779 | ||
780 | ogm_offset += BATADV_OGM2_HLEN; | |
781 | ogm_offset += ntohs(ogm_packet->tvlv_len); | |
782 | ||
783 | packet_pos = skb->data + ogm_offset; | |
784 | ogm_packet = (struct batadv_ogm2_packet *)packet_pos; | |
785 | } | |
786 | ||
787 | ret = NET_RX_SUCCESS; | |
0da00359 | 788 | consume_skb(skb); |
9323158e AQ |
789 | |
790 | return ret; | |
0da00359 AQ |
791 | } |
792 | ||
793 | /** | |
794 | * batadv_v_ogm_init - initialise the OGM2 engine | |
795 | * @bat_priv: the bat priv with all the soft interface information | |
796 | * | |
797 | * Return: 0 on success or a negative error code in case of failure | |
798 | */ | |
799 | int batadv_v_ogm_init(struct batadv_priv *bat_priv) | |
800 | { | |
801 | struct batadv_ogm2_packet *ogm_packet; | |
802 | unsigned char *ogm_buff; | |
803 | u32 random_seqno; | |
804 | ||
805 | bat_priv->bat_v.ogm_buff_len = BATADV_OGM2_HLEN; | |
806 | ogm_buff = kzalloc(bat_priv->bat_v.ogm_buff_len, GFP_ATOMIC); | |
807 | if (!ogm_buff) | |
808 | return -ENOMEM; | |
809 | ||
810 | bat_priv->bat_v.ogm_buff = ogm_buff; | |
811 | ogm_packet = (struct batadv_ogm2_packet *)ogm_buff; | |
812 | ogm_packet->packet_type = BATADV_OGM2; | |
813 | ogm_packet->version = BATADV_COMPAT_VERSION; | |
814 | ogm_packet->ttl = BATADV_TTL; | |
815 | ogm_packet->flags = BATADV_NO_FLAGS; | |
816 | ogm_packet->throughput = htonl(BATADV_THROUGHPUT_MAX_VALUE); | |
817 | ||
818 | /* randomize initial seqno to avoid collision */ | |
819 | get_random_bytes(&random_seqno, sizeof(random_seqno)); | |
820 | atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno); | |
821 | INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send); | |
822 | ||
823 | return 0; | |
824 | } | |
825 | ||
826 | /** | |
827 | * batadv_v_ogm_free - free OGM private resources | |
828 | * @bat_priv: the bat priv with all the soft interface information | |
829 | */ | |
830 | void batadv_v_ogm_free(struct batadv_priv *bat_priv) | |
831 | { | |
832 | cancel_delayed_work_sync(&bat_priv->bat_v.ogm_wq); | |
833 | ||
834 | kfree(bat_priv->bat_v.ogm_buff); | |
835 | bat_priv->bat_v.ogm_buff = NULL; | |
836 | bat_priv->bat_v.ogm_buff_len = 0; | |
837 | } |