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