xref: /openbmc/linux/net/batman-adv/bat_iv_ogm.c (revision f519f0be)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich
5  */
6 
7 #include "bat_iv_ogm.h"
8 #include "main.h"
9 
10 #include <linux/atomic.h>
11 #include <linux/bitmap.h>
12 #include <linux/bitops.h>
13 #include <linux/bug.h>
14 #include <linux/byteorder/generic.h>
15 #include <linux/cache.h>
16 #include <linux/errno.h>
17 #include <linux/etherdevice.h>
18 #include <linux/gfp.h>
19 #include <linux/if_ether.h>
20 #include <linux/init.h>
21 #include <linux/jiffies.h>
22 #include <linux/kernel.h>
23 #include <linux/kref.h>
24 #include <linux/list.h>
25 #include <linux/netdevice.h>
26 #include <linux/netlink.h>
27 #include <linux/pkt_sched.h>
28 #include <linux/printk.h>
29 #include <linux/random.h>
30 #include <linux/rculist.h>
31 #include <linux/rcupdate.h>
32 #include <linux/seq_file.h>
33 #include <linux/skbuff.h>
34 #include <linux/slab.h>
35 #include <linux/spinlock.h>
36 #include <linux/stddef.h>
37 #include <linux/string.h>
38 #include <linux/types.h>
39 #include <linux/workqueue.h>
40 #include <net/genetlink.h>
41 #include <net/netlink.h>
42 #include <uapi/linux/batadv_packet.h>
43 #include <uapi/linux/batman_adv.h>
44 
45 #include "bat_algo.h"
46 #include "bitarray.h"
47 #include "gateway_client.h"
48 #include "hard-interface.h"
49 #include "hash.h"
50 #include "log.h"
51 #include "netlink.h"
52 #include "network-coding.h"
53 #include "originator.h"
54 #include "routing.h"
55 #include "send.h"
56 #include "translation-table.h"
57 #include "tvlv.h"
58 
59 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work);
60 
61 /**
62  * enum batadv_dup_status - duplicate status
63  */
64 enum batadv_dup_status {
65 	/** @BATADV_NO_DUP: the packet is no duplicate */
66 	BATADV_NO_DUP = 0,
67 
68 	/**
69 	 * @BATADV_ORIG_DUP: OGM is a duplicate in the originator (but not for
70 	 *  the neighbor)
71 	 */
72 	BATADV_ORIG_DUP,
73 
74 	/** @BATADV_NEIGH_DUP: OGM is a duplicate for the neighbor */
75 	BATADV_NEIGH_DUP,
76 
77 	/**
78 	 * @BATADV_PROTECTED: originator is currently protected (after reboot)
79 	 */
80 	BATADV_PROTECTED,
81 };
82 
83 /**
84  * batadv_ring_buffer_set() - update the ring buffer with the given value
85  * @lq_recv: pointer to the ring buffer
86  * @lq_index: index to store the value at
87  * @value: value to store in the ring buffer
88  */
89 static void batadv_ring_buffer_set(u8 lq_recv[], u8 *lq_index, u8 value)
90 {
91 	lq_recv[*lq_index] = value;
92 	*lq_index = (*lq_index + 1) % BATADV_TQ_GLOBAL_WINDOW_SIZE;
93 }
94 
95 /**
96  * batadv_ring_buffer_avg() - compute the average of all non-zero values stored
97  * in the given ring buffer
98  * @lq_recv: pointer to the ring buffer
99  *
100  * Return: computed average value.
101  */
102 static u8 batadv_ring_buffer_avg(const u8 lq_recv[])
103 {
104 	const u8 *ptr;
105 	u16 count = 0;
106 	u16 i = 0;
107 	u16 sum = 0;
108 
109 	ptr = lq_recv;
110 
111 	while (i < BATADV_TQ_GLOBAL_WINDOW_SIZE) {
112 		if (*ptr != 0) {
113 			count++;
114 			sum += *ptr;
115 		}
116 
117 		i++;
118 		ptr++;
119 	}
120 
121 	if (count == 0)
122 		return 0;
123 
124 	return (u8)(sum / count);
125 }
126 
127 /**
128  * batadv_iv_ogm_orig_get() - retrieve or create (if does not exist) an
129  *  originator
130  * @bat_priv: the bat priv with all the soft interface information
131  * @addr: mac address of the originator
132  *
133  * Return: the originator object corresponding to the passed mac address or NULL
134  * on failure.
135  * If the object does not exists it is created an initialised.
136  */
137 static struct batadv_orig_node *
138 batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const u8 *addr)
139 {
140 	struct batadv_orig_node *orig_node;
141 	int hash_added;
142 
143 	orig_node = batadv_orig_hash_find(bat_priv, addr);
144 	if (orig_node)
145 		return orig_node;
146 
147 	orig_node = batadv_orig_node_new(bat_priv, addr);
148 	if (!orig_node)
149 		return NULL;
150 
151 	spin_lock_init(&orig_node->bat_iv.ogm_cnt_lock);
152 
153 	kref_get(&orig_node->refcount);
154 	hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
155 				     batadv_choose_orig, orig_node,
156 				     &orig_node->hash_entry);
157 	if (hash_added != 0)
158 		goto free_orig_node_hash;
159 
160 	return orig_node;
161 
162 free_orig_node_hash:
163 	/* reference for batadv_hash_add */
164 	batadv_orig_node_put(orig_node);
165 	/* reference from batadv_orig_node_new */
166 	batadv_orig_node_put(orig_node);
167 
168 	return NULL;
169 }
170 
171 static struct batadv_neigh_node *
172 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
173 			const u8 *neigh_addr,
174 			struct batadv_orig_node *orig_node,
175 			struct batadv_orig_node *orig_neigh)
176 {
177 	struct batadv_neigh_node *neigh_node;
178 
179 	neigh_node = batadv_neigh_node_get_or_create(orig_node,
180 						     hard_iface, neigh_addr);
181 	if (!neigh_node)
182 		goto out;
183 
184 	neigh_node->orig_node = orig_neigh;
185 
186 out:
187 	return neigh_node;
188 }
189 
190 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
191 {
192 	struct batadv_ogm_packet *batadv_ogm_packet;
193 	unsigned char *ogm_buff;
194 	u32 random_seqno;
195 
196 	/* randomize initial seqno to avoid collision */
197 	get_random_bytes(&random_seqno, sizeof(random_seqno));
198 	atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
199 
200 	hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
201 	ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
202 	if (!ogm_buff)
203 		return -ENOMEM;
204 
205 	hard_iface->bat_iv.ogm_buff = ogm_buff;
206 
207 	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
208 	batadv_ogm_packet->packet_type = BATADV_IV_OGM;
209 	batadv_ogm_packet->version = BATADV_COMPAT_VERSION;
210 	batadv_ogm_packet->ttl = 2;
211 	batadv_ogm_packet->flags = BATADV_NO_FLAGS;
212 	batadv_ogm_packet->reserved = 0;
213 	batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
214 
215 	return 0;
216 }
217 
218 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
219 {
220 	kfree(hard_iface->bat_iv.ogm_buff);
221 	hard_iface->bat_iv.ogm_buff = NULL;
222 }
223 
224 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
225 {
226 	struct batadv_ogm_packet *batadv_ogm_packet;
227 	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
228 
229 	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
230 	ether_addr_copy(batadv_ogm_packet->orig,
231 			hard_iface->net_dev->dev_addr);
232 	ether_addr_copy(batadv_ogm_packet->prev_sender,
233 			hard_iface->net_dev->dev_addr);
234 }
235 
236 static void
237 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
238 {
239 	struct batadv_ogm_packet *batadv_ogm_packet;
240 	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
241 
242 	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
243 	batadv_ogm_packet->ttl = BATADV_TTL;
244 }
245 
246 /* when do we schedule our own ogm to be sent */
247 static unsigned long
248 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
249 {
250 	unsigned int msecs;
251 
252 	msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
253 	msecs += prandom_u32() % (2 * BATADV_JITTER);
254 
255 	return jiffies + msecs_to_jiffies(msecs);
256 }
257 
258 /* when do we schedule a ogm packet to be sent */
259 static unsigned long batadv_iv_ogm_fwd_send_time(void)
260 {
261 	return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
262 }
263 
264 /* apply hop penalty for a normal link */
265 static u8 batadv_hop_penalty(u8 tq, const struct batadv_priv *bat_priv)
266 {
267 	int hop_penalty = atomic_read(&bat_priv->hop_penalty);
268 	int new_tq;
269 
270 	new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
271 	new_tq /= BATADV_TQ_MAX_VALUE;
272 
273 	return new_tq;
274 }
275 
276 /**
277  * batadv_iv_ogm_aggr_packet() - checks if there is another OGM attached
278  * @buff_pos: current position in the skb
279  * @packet_len: total length of the skb
280  * @tvlv_len: tvlv length of the previously considered OGM
281  *
282  * Return: true if there is enough space for another OGM, false otherwise.
283  */
284 static bool batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
285 				      __be16 tvlv_len)
286 {
287 	int next_buff_pos = 0;
288 
289 	next_buff_pos += buff_pos + BATADV_OGM_HLEN;
290 	next_buff_pos += ntohs(tvlv_len);
291 
292 	return (next_buff_pos <= packet_len) &&
293 	       (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
294 }
295 
296 /* send a batman ogm to a given interface */
297 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
298 				     struct batadv_hard_iface *hard_iface)
299 {
300 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
301 	const char *fwd_str;
302 	u8 packet_num;
303 	s16 buff_pos;
304 	struct batadv_ogm_packet *batadv_ogm_packet;
305 	struct sk_buff *skb;
306 	u8 *packet_pos;
307 
308 	if (hard_iface->if_status != BATADV_IF_ACTIVE)
309 		return;
310 
311 	packet_num = 0;
312 	buff_pos = 0;
313 	packet_pos = forw_packet->skb->data;
314 	batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
315 
316 	/* adjust all flags and log packets */
317 	while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
318 					 batadv_ogm_packet->tvlv_len)) {
319 		/* we might have aggregated direct link packets with an
320 		 * ordinary base packet
321 		 */
322 		if (forw_packet->direct_link_flags & BIT(packet_num) &&
323 		    forw_packet->if_incoming == hard_iface)
324 			batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
325 		else
326 			batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
327 
328 		if (packet_num > 0 || !forw_packet->own)
329 			fwd_str = "Forwarding";
330 		else
331 			fwd_str = "Sending own";
332 
333 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
334 			   "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s) on interface %s [%pM]\n",
335 			   fwd_str, (packet_num > 0 ? "aggregated " : ""),
336 			   batadv_ogm_packet->orig,
337 			   ntohl(batadv_ogm_packet->seqno),
338 			   batadv_ogm_packet->tq, batadv_ogm_packet->ttl,
339 			   ((batadv_ogm_packet->flags & BATADV_DIRECTLINK) ?
340 			    "on" : "off"),
341 			   hard_iface->net_dev->name,
342 			   hard_iface->net_dev->dev_addr);
343 
344 		buff_pos += BATADV_OGM_HLEN;
345 		buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
346 		packet_num++;
347 		packet_pos = forw_packet->skb->data + buff_pos;
348 		batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
349 	}
350 
351 	/* create clone because function is called more than once */
352 	skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
353 	if (skb) {
354 		batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
355 		batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
356 				   skb->len + ETH_HLEN);
357 		batadv_send_broadcast_skb(skb, hard_iface);
358 	}
359 }
360 
361 /* send a batman ogm packet */
362 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
363 {
364 	struct net_device *soft_iface;
365 
366 	if (!forw_packet->if_incoming) {
367 		pr_err("Error - can't forward packet: incoming iface not specified\n");
368 		return;
369 	}
370 
371 	soft_iface = forw_packet->if_incoming->soft_iface;
372 
373 	if (WARN_ON(!forw_packet->if_outgoing))
374 		return;
375 
376 	if (WARN_ON(forw_packet->if_outgoing->soft_iface != soft_iface))
377 		return;
378 
379 	if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
380 		return;
381 
382 	/* only for one specific outgoing interface */
383 	batadv_iv_ogm_send_to_if(forw_packet, forw_packet->if_outgoing);
384 }
385 
386 /**
387  * batadv_iv_ogm_can_aggregate() - find out if an OGM can be aggregated on an
388  *  existing forward packet
389  * @new_bat_ogm_packet: OGM packet to be aggregated
390  * @bat_priv: the bat priv with all the soft interface information
391  * @packet_len: (total) length of the OGM
392  * @send_time: timestamp (jiffies) when the packet is to be sent
393  * @directlink: true if this is a direct link packet
394  * @if_incoming: interface where the packet was received
395  * @if_outgoing: interface for which the retransmission should be considered
396  * @forw_packet: the forwarded packet which should be checked
397  *
398  * Return: true if new_packet can be aggregated with forw_packet
399  */
400 static bool
401 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
402 			    struct batadv_priv *bat_priv,
403 			    int packet_len, unsigned long send_time,
404 			    bool directlink,
405 			    const struct batadv_hard_iface *if_incoming,
406 			    const struct batadv_hard_iface *if_outgoing,
407 			    const struct batadv_forw_packet *forw_packet)
408 {
409 	struct batadv_ogm_packet *batadv_ogm_packet;
410 	int aggregated_bytes = forw_packet->packet_len + packet_len;
411 	struct batadv_hard_iface *primary_if = NULL;
412 	bool res = false;
413 	unsigned long aggregation_end_time;
414 
415 	batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
416 	aggregation_end_time = send_time;
417 	aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
418 
419 	/* we can aggregate the current packet to this aggregated packet
420 	 * if:
421 	 *
422 	 * - the send time is within our MAX_AGGREGATION_MS time
423 	 * - the resulting packet wont be bigger than
424 	 *   MAX_AGGREGATION_BYTES
425 	 * otherwise aggregation is not possible
426 	 */
427 	if (!time_before(send_time, forw_packet->send_time) ||
428 	    !time_after_eq(aggregation_end_time, forw_packet->send_time))
429 		return false;
430 
431 	if (aggregated_bytes > BATADV_MAX_AGGREGATION_BYTES)
432 		return false;
433 
434 	/* packet is not leaving on the same interface. */
435 	if (forw_packet->if_outgoing != if_outgoing)
436 		return false;
437 
438 	/* check aggregation compatibility
439 	 * -> direct link packets are broadcasted on
440 	 *    their interface only
441 	 * -> aggregate packet if the current packet is
442 	 *    a "global" packet as well as the base
443 	 *    packet
444 	 */
445 	primary_if = batadv_primary_if_get_selected(bat_priv);
446 	if (!primary_if)
447 		return false;
448 
449 	/* packets without direct link flag and high TTL
450 	 * are flooded through the net
451 	 */
452 	if (!directlink &&
453 	    !(batadv_ogm_packet->flags & BATADV_DIRECTLINK) &&
454 	    batadv_ogm_packet->ttl != 1 &&
455 
456 	    /* own packets originating non-primary
457 	     * interfaces leave only that interface
458 	     */
459 	    (!forw_packet->own ||
460 	     forw_packet->if_incoming == primary_if)) {
461 		res = true;
462 		goto out;
463 	}
464 
465 	/* if the incoming packet is sent via this one
466 	 * interface only - we still can aggregate
467 	 */
468 	if (directlink &&
469 	    new_bat_ogm_packet->ttl == 1 &&
470 	    forw_packet->if_incoming == if_incoming &&
471 
472 	    /* packets from direct neighbors or
473 	     * own secondary interface packets
474 	     * (= secondary interface packets in general)
475 	     */
476 	    (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
477 	     (forw_packet->own &&
478 	      forw_packet->if_incoming != primary_if))) {
479 		res = true;
480 		goto out;
481 	}
482 
483 out:
484 	if (primary_if)
485 		batadv_hardif_put(primary_if);
486 	return res;
487 }
488 
489 /**
490  * batadv_iv_ogm_aggregate_new() - create a new aggregated packet and add this
491  *  packet to it.
492  * @packet_buff: pointer to the OGM
493  * @packet_len: (total) length of the OGM
494  * @send_time: timestamp (jiffies) when the packet is to be sent
495  * @direct_link: whether this OGM has direct link status
496  * @if_incoming: interface where the packet was received
497  * @if_outgoing: interface for which the retransmission should be considered
498  * @own_packet: true if it is a self-generated ogm
499  */
500 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
501 					int packet_len, unsigned long send_time,
502 					bool direct_link,
503 					struct batadv_hard_iface *if_incoming,
504 					struct batadv_hard_iface *if_outgoing,
505 					int own_packet)
506 {
507 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
508 	struct batadv_forw_packet *forw_packet_aggr;
509 	struct sk_buff *skb;
510 	unsigned char *skb_buff;
511 	unsigned int skb_size;
512 	atomic_t *queue_left = own_packet ? NULL : &bat_priv->batman_queue_left;
513 
514 	if (atomic_read(&bat_priv->aggregated_ogms) &&
515 	    packet_len < BATADV_MAX_AGGREGATION_BYTES)
516 		skb_size = BATADV_MAX_AGGREGATION_BYTES;
517 	else
518 		skb_size = packet_len;
519 
520 	skb_size += ETH_HLEN;
521 
522 	skb = netdev_alloc_skb_ip_align(NULL, skb_size);
523 	if (!skb)
524 		return;
525 
526 	forw_packet_aggr = batadv_forw_packet_alloc(if_incoming, if_outgoing,
527 						    queue_left, bat_priv, skb);
528 	if (!forw_packet_aggr) {
529 		kfree_skb(skb);
530 		return;
531 	}
532 
533 	forw_packet_aggr->skb->priority = TC_PRIO_CONTROL;
534 	skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
535 
536 	skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
537 	forw_packet_aggr->packet_len = packet_len;
538 	memcpy(skb_buff, packet_buff, packet_len);
539 
540 	forw_packet_aggr->own = own_packet;
541 	forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
542 	forw_packet_aggr->send_time = send_time;
543 
544 	/* save packet direct link flag status */
545 	if (direct_link)
546 		forw_packet_aggr->direct_link_flags |= 1;
547 
548 	INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
549 			  batadv_iv_send_outstanding_bat_ogm_packet);
550 
551 	batadv_forw_packet_ogmv1_queue(bat_priv, forw_packet_aggr, send_time);
552 }
553 
554 /* aggregate a new packet into the existing ogm packet */
555 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
556 				    const unsigned char *packet_buff,
557 				    int packet_len, bool direct_link)
558 {
559 	unsigned long new_direct_link_flag;
560 
561 	skb_put_data(forw_packet_aggr->skb, packet_buff, packet_len);
562 	forw_packet_aggr->packet_len += packet_len;
563 	forw_packet_aggr->num_packets++;
564 
565 	/* save packet direct link flag status */
566 	if (direct_link) {
567 		new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
568 		forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
569 	}
570 }
571 
572 /**
573  * batadv_iv_ogm_queue_add() - queue up an OGM for transmission
574  * @bat_priv: the bat priv with all the soft interface information
575  * @packet_buff: pointer to the OGM
576  * @packet_len: (total) length of the OGM
577  * @if_incoming: interface where the packet was received
578  * @if_outgoing: interface for which the retransmission should be considered
579  * @own_packet: true if it is a self-generated ogm
580  * @send_time: timestamp (jiffies) when the packet is to be sent
581  */
582 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
583 				    unsigned char *packet_buff,
584 				    int packet_len,
585 				    struct batadv_hard_iface *if_incoming,
586 				    struct batadv_hard_iface *if_outgoing,
587 				    int own_packet, unsigned long send_time)
588 {
589 	/* _aggr -> pointer to the packet we want to aggregate with
590 	 * _pos -> pointer to the position in the queue
591 	 */
592 	struct batadv_forw_packet *forw_packet_aggr = NULL;
593 	struct batadv_forw_packet *forw_packet_pos = NULL;
594 	struct batadv_ogm_packet *batadv_ogm_packet;
595 	bool direct_link;
596 	unsigned long max_aggregation_jiffies;
597 
598 	batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
599 	direct_link = !!(batadv_ogm_packet->flags & BATADV_DIRECTLINK);
600 	max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
601 
602 	/* find position for the packet in the forward queue */
603 	spin_lock_bh(&bat_priv->forw_bat_list_lock);
604 	/* own packets are not to be aggregated */
605 	if (atomic_read(&bat_priv->aggregated_ogms) && !own_packet) {
606 		hlist_for_each_entry(forw_packet_pos,
607 				     &bat_priv->forw_bat_list, list) {
608 			if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
609 							bat_priv, packet_len,
610 							send_time, direct_link,
611 							if_incoming,
612 							if_outgoing,
613 							forw_packet_pos)) {
614 				forw_packet_aggr = forw_packet_pos;
615 				break;
616 			}
617 		}
618 	}
619 
620 	/* nothing to aggregate with - either aggregation disabled or no
621 	 * suitable aggregation packet found
622 	 */
623 	if (!forw_packet_aggr) {
624 		/* the following section can run without the lock */
625 		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
626 
627 		/* if we could not aggregate this packet with one of the others
628 		 * we hold it back for a while, so that it might be aggregated
629 		 * later on
630 		 */
631 		if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
632 			send_time += max_aggregation_jiffies;
633 
634 		batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
635 					    send_time, direct_link,
636 					    if_incoming, if_outgoing,
637 					    own_packet);
638 	} else {
639 		batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
640 					packet_len, direct_link);
641 		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
642 	}
643 }
644 
645 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
646 				  const struct ethhdr *ethhdr,
647 				  struct batadv_ogm_packet *batadv_ogm_packet,
648 				  bool is_single_hop_neigh,
649 				  bool is_from_best_next_hop,
650 				  struct batadv_hard_iface *if_incoming,
651 				  struct batadv_hard_iface *if_outgoing)
652 {
653 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
654 	u16 tvlv_len;
655 
656 	if (batadv_ogm_packet->ttl <= 1) {
657 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
658 		return;
659 	}
660 
661 	if (!is_from_best_next_hop) {
662 		/* Mark the forwarded packet when it is not coming from our
663 		 * best next hop. We still need to forward the packet for our
664 		 * neighbor link quality detection to work in case the packet
665 		 * originated from a single hop neighbor. Otherwise we can
666 		 * simply drop the ogm.
667 		 */
668 		if (is_single_hop_neigh)
669 			batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
670 		else
671 			return;
672 	}
673 
674 	tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
675 
676 	batadv_ogm_packet->ttl--;
677 	ether_addr_copy(batadv_ogm_packet->prev_sender, ethhdr->h_source);
678 
679 	/* apply hop penalty */
680 	batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
681 						   bat_priv);
682 
683 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
684 		   "Forwarding packet: tq: %i, ttl: %i\n",
685 		   batadv_ogm_packet->tq, batadv_ogm_packet->ttl);
686 
687 	if (is_single_hop_neigh)
688 		batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
689 	else
690 		batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
691 
692 	batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
693 				BATADV_OGM_HLEN + tvlv_len,
694 				if_incoming, if_outgoing, 0,
695 				batadv_iv_ogm_fwd_send_time());
696 }
697 
698 /**
699  * batadv_iv_ogm_slide_own_bcast_window() - bitshift own OGM broadcast windows
700  *  for the given interface
701  * @hard_iface: the interface for which the windows have to be shifted
702  */
703 static void
704 batadv_iv_ogm_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
705 {
706 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
707 	struct batadv_hashtable *hash = bat_priv->orig_hash;
708 	struct hlist_head *head;
709 	struct batadv_orig_node *orig_node;
710 	struct batadv_orig_ifinfo *orig_ifinfo;
711 	unsigned long *word;
712 	u32 i;
713 	u8 *w;
714 
715 	for (i = 0; i < hash->size; i++) {
716 		head = &hash->table[i];
717 
718 		rcu_read_lock();
719 		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
720 			hlist_for_each_entry_rcu(orig_ifinfo,
721 						 &orig_node->ifinfo_list,
722 						 list) {
723 				if (orig_ifinfo->if_outgoing != hard_iface)
724 					continue;
725 
726 				spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
727 				word = orig_ifinfo->bat_iv.bcast_own;
728 				batadv_bit_get_packet(bat_priv, word, 1, 0);
729 				w = &orig_ifinfo->bat_iv.bcast_own_sum;
730 				*w = bitmap_weight(word,
731 						   BATADV_TQ_LOCAL_WINDOW_SIZE);
732 				spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
733 			}
734 		}
735 		rcu_read_unlock();
736 	}
737 }
738 
739 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
740 {
741 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
742 	unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
743 	struct batadv_ogm_packet *batadv_ogm_packet;
744 	struct batadv_hard_iface *primary_if, *tmp_hard_iface;
745 	int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
746 	u32 seqno;
747 	u16 tvlv_len = 0;
748 	unsigned long send_time;
749 
750 	if (hard_iface->if_status == BATADV_IF_NOT_IN_USE ||
751 	    hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)
752 		return;
753 
754 	/* the interface gets activated here to avoid race conditions between
755 	 * the moment of activating the interface in
756 	 * hardif_activate_interface() where the originator mac is set and
757 	 * outdated packets (especially uninitialized mac addresses) in the
758 	 * packet queue
759 	 */
760 	if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
761 		hard_iface->if_status = BATADV_IF_ACTIVE;
762 
763 	primary_if = batadv_primary_if_get_selected(bat_priv);
764 
765 	if (hard_iface == primary_if) {
766 		/* tt changes have to be committed before the tvlv data is
767 		 * appended as it may alter the tt tvlv container
768 		 */
769 		batadv_tt_local_commit_changes(bat_priv);
770 		tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
771 							    ogm_buff_len,
772 							    BATADV_OGM_HLEN);
773 	}
774 
775 	batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
776 	batadv_ogm_packet->tvlv_len = htons(tvlv_len);
777 
778 	/* change sequence number to network order */
779 	seqno = (u32)atomic_read(&hard_iface->bat_iv.ogm_seqno);
780 	batadv_ogm_packet->seqno = htonl(seqno);
781 	atomic_inc(&hard_iface->bat_iv.ogm_seqno);
782 
783 	batadv_iv_ogm_slide_own_bcast_window(hard_iface);
784 
785 	send_time = batadv_iv_ogm_emit_send_time(bat_priv);
786 
787 	if (hard_iface != primary_if) {
788 		/* OGMs from secondary interfaces are only scheduled on their
789 		 * respective interfaces.
790 		 */
791 		batadv_iv_ogm_queue_add(bat_priv, *ogm_buff, *ogm_buff_len,
792 					hard_iface, hard_iface, 1, send_time);
793 		goto out;
794 	}
795 
796 	/* OGMs from primary interfaces are scheduled on all
797 	 * interfaces.
798 	 */
799 	rcu_read_lock();
800 	list_for_each_entry_rcu(tmp_hard_iface, &batadv_hardif_list, list) {
801 		if (tmp_hard_iface->soft_iface != hard_iface->soft_iface)
802 			continue;
803 
804 		if (!kref_get_unless_zero(&tmp_hard_iface->refcount))
805 			continue;
806 
807 		batadv_iv_ogm_queue_add(bat_priv, *ogm_buff,
808 					*ogm_buff_len, hard_iface,
809 					tmp_hard_iface, 1, send_time);
810 
811 		batadv_hardif_put(tmp_hard_iface);
812 	}
813 	rcu_read_unlock();
814 
815 out:
816 	if (primary_if)
817 		batadv_hardif_put(primary_if);
818 }
819 
820 /**
821  * batadv_iv_orig_ifinfo_sum() - Get bcast_own sum for originator over iterface
822  * @orig_node: originator which reproadcasted the OGMs directly
823  * @if_outgoing: interface which transmitted the original OGM and received the
824  *  direct rebroadcast
825  *
826  * Return: Number of replied (rebroadcasted) OGMs which were transmitted by
827  *  an originator and directly (without intermediate hop) received by a specific
828  *  interface
829  */
830 static u8 batadv_iv_orig_ifinfo_sum(struct batadv_orig_node *orig_node,
831 				    struct batadv_hard_iface *if_outgoing)
832 {
833 	struct batadv_orig_ifinfo *orig_ifinfo;
834 	u8 sum;
835 
836 	orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_outgoing);
837 	if (!orig_ifinfo)
838 		return 0;
839 
840 	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
841 	sum = orig_ifinfo->bat_iv.bcast_own_sum;
842 	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
843 
844 	batadv_orig_ifinfo_put(orig_ifinfo);
845 
846 	return sum;
847 }
848 
849 /**
850  * batadv_iv_ogm_orig_update() - use OGM to update corresponding data in an
851  *  originator
852  * @bat_priv: the bat priv with all the soft interface information
853  * @orig_node: the orig node who originally emitted the ogm packet
854  * @orig_ifinfo: ifinfo for the outgoing interface of the orig_node
855  * @ethhdr: Ethernet header of the OGM
856  * @batadv_ogm_packet: the ogm packet
857  * @if_incoming: interface where the packet was received
858  * @if_outgoing: interface for which the retransmission should be considered
859  * @dup_status: the duplicate status of this ogm packet.
860  */
861 static void
862 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
863 			  struct batadv_orig_node *orig_node,
864 			  struct batadv_orig_ifinfo *orig_ifinfo,
865 			  const struct ethhdr *ethhdr,
866 			  const struct batadv_ogm_packet *batadv_ogm_packet,
867 			  struct batadv_hard_iface *if_incoming,
868 			  struct batadv_hard_iface *if_outgoing,
869 			  enum batadv_dup_status dup_status)
870 {
871 	struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
872 	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
873 	struct batadv_neigh_node *neigh_node = NULL;
874 	struct batadv_neigh_node *tmp_neigh_node = NULL;
875 	struct batadv_neigh_node *router = NULL;
876 	u8 sum_orig, sum_neigh;
877 	u8 *neigh_addr;
878 	u8 tq_avg;
879 
880 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
881 		   "%s(): Searching and updating originator entry of received packet\n",
882 		   __func__);
883 
884 	rcu_read_lock();
885 	hlist_for_each_entry_rcu(tmp_neigh_node,
886 				 &orig_node->neigh_list, list) {
887 		neigh_addr = tmp_neigh_node->addr;
888 		if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
889 		    tmp_neigh_node->if_incoming == if_incoming &&
890 		    kref_get_unless_zero(&tmp_neigh_node->refcount)) {
891 			if (WARN(neigh_node, "too many matching neigh_nodes"))
892 				batadv_neigh_node_put(neigh_node);
893 			neigh_node = tmp_neigh_node;
894 			continue;
895 		}
896 
897 		if (dup_status != BATADV_NO_DUP)
898 			continue;
899 
900 		/* only update the entry for this outgoing interface */
901 		neigh_ifinfo = batadv_neigh_ifinfo_get(tmp_neigh_node,
902 						       if_outgoing);
903 		if (!neigh_ifinfo)
904 			continue;
905 
906 		spin_lock_bh(&tmp_neigh_node->ifinfo_lock);
907 		batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
908 				       &neigh_ifinfo->bat_iv.tq_index, 0);
909 		tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
910 		neigh_ifinfo->bat_iv.tq_avg = tq_avg;
911 		spin_unlock_bh(&tmp_neigh_node->ifinfo_lock);
912 
913 		batadv_neigh_ifinfo_put(neigh_ifinfo);
914 		neigh_ifinfo = NULL;
915 	}
916 
917 	if (!neigh_node) {
918 		struct batadv_orig_node *orig_tmp;
919 
920 		orig_tmp = batadv_iv_ogm_orig_get(bat_priv, ethhdr->h_source);
921 		if (!orig_tmp)
922 			goto unlock;
923 
924 		neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
925 						     ethhdr->h_source,
926 						     orig_node, orig_tmp);
927 
928 		batadv_orig_node_put(orig_tmp);
929 		if (!neigh_node)
930 			goto unlock;
931 	} else {
932 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
933 			   "Updating existing last-hop neighbor of originator\n");
934 	}
935 
936 	rcu_read_unlock();
937 	neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
938 	if (!neigh_ifinfo)
939 		goto out;
940 
941 	neigh_node->last_seen = jiffies;
942 
943 	spin_lock_bh(&neigh_node->ifinfo_lock);
944 	batadv_ring_buffer_set(neigh_ifinfo->bat_iv.tq_recv,
945 			       &neigh_ifinfo->bat_iv.tq_index,
946 			       batadv_ogm_packet->tq);
947 	tq_avg = batadv_ring_buffer_avg(neigh_ifinfo->bat_iv.tq_recv);
948 	neigh_ifinfo->bat_iv.tq_avg = tq_avg;
949 	spin_unlock_bh(&neigh_node->ifinfo_lock);
950 
951 	if (dup_status == BATADV_NO_DUP) {
952 		orig_ifinfo->last_ttl = batadv_ogm_packet->ttl;
953 		neigh_ifinfo->last_ttl = batadv_ogm_packet->ttl;
954 	}
955 
956 	/* if this neighbor already is our next hop there is nothing
957 	 * to change
958 	 */
959 	router = batadv_orig_router_get(orig_node, if_outgoing);
960 	if (router == neigh_node)
961 		goto out;
962 
963 	if (router) {
964 		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
965 		if (!router_ifinfo)
966 			goto out;
967 
968 		/* if this neighbor does not offer a better TQ we won't
969 		 * consider it
970 		 */
971 		if (router_ifinfo->bat_iv.tq_avg > neigh_ifinfo->bat_iv.tq_avg)
972 			goto out;
973 	}
974 
975 	/* if the TQ is the same and the link not more symmetric we
976 	 * won't consider it either
977 	 */
978 	if (router_ifinfo &&
979 	    neigh_ifinfo->bat_iv.tq_avg == router_ifinfo->bat_iv.tq_avg) {
980 		sum_orig = batadv_iv_orig_ifinfo_sum(router->orig_node,
981 						     router->if_incoming);
982 		sum_neigh = batadv_iv_orig_ifinfo_sum(neigh_node->orig_node,
983 						      neigh_node->if_incoming);
984 		if (sum_orig >= sum_neigh)
985 			goto out;
986 	}
987 
988 	batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
989 	goto out;
990 
991 unlock:
992 	rcu_read_unlock();
993 out:
994 	if (neigh_node)
995 		batadv_neigh_node_put(neigh_node);
996 	if (router)
997 		batadv_neigh_node_put(router);
998 	if (neigh_ifinfo)
999 		batadv_neigh_ifinfo_put(neigh_ifinfo);
1000 	if (router_ifinfo)
1001 		batadv_neigh_ifinfo_put(router_ifinfo);
1002 }
1003 
1004 /**
1005  * batadv_iv_ogm_calc_tq() - calculate tq for current received ogm packet
1006  * @orig_node: the orig node who originally emitted the ogm packet
1007  * @orig_neigh_node: the orig node struct of the neighbor who sent the packet
1008  * @batadv_ogm_packet: the ogm packet
1009  * @if_incoming: interface where the packet was received
1010  * @if_outgoing: interface for which the retransmission should be considered
1011  *
1012  * Return: true if the link can be considered bidirectional, false otherwise
1013  */
1014 static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
1015 				  struct batadv_orig_node *orig_neigh_node,
1016 				  struct batadv_ogm_packet *batadv_ogm_packet,
1017 				  struct batadv_hard_iface *if_incoming,
1018 				  struct batadv_hard_iface *if_outgoing)
1019 {
1020 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1021 	struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
1022 	struct batadv_neigh_ifinfo *neigh_ifinfo;
1023 	u8 total_count;
1024 	u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
1025 	unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
1026 	unsigned int tq_asym_penalty, inv_asym_penalty;
1027 	unsigned int combined_tq;
1028 	unsigned int tq_iface_penalty;
1029 	bool ret = false;
1030 
1031 	/* find corresponding one hop neighbor */
1032 	rcu_read_lock();
1033 	hlist_for_each_entry_rcu(tmp_neigh_node,
1034 				 &orig_neigh_node->neigh_list, list) {
1035 		if (!batadv_compare_eth(tmp_neigh_node->addr,
1036 					orig_neigh_node->orig))
1037 			continue;
1038 
1039 		if (tmp_neigh_node->if_incoming != if_incoming)
1040 			continue;
1041 
1042 		if (!kref_get_unless_zero(&tmp_neigh_node->refcount))
1043 			continue;
1044 
1045 		neigh_node = tmp_neigh_node;
1046 		break;
1047 	}
1048 	rcu_read_unlock();
1049 
1050 	if (!neigh_node)
1051 		neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
1052 						     orig_neigh_node->orig,
1053 						     orig_neigh_node,
1054 						     orig_neigh_node);
1055 
1056 	if (!neigh_node)
1057 		goto out;
1058 
1059 	/* if orig_node is direct neighbor update neigh_node last_seen */
1060 	if (orig_node == orig_neigh_node)
1061 		neigh_node->last_seen = jiffies;
1062 
1063 	orig_node->last_seen = jiffies;
1064 
1065 	/* find packet count of corresponding one hop neighbor */
1066 	orig_eq_count = batadv_iv_orig_ifinfo_sum(orig_neigh_node, if_incoming);
1067 	neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
1068 	if (neigh_ifinfo) {
1069 		neigh_rq_count = neigh_ifinfo->bat_iv.real_packet_count;
1070 		batadv_neigh_ifinfo_put(neigh_ifinfo);
1071 	} else {
1072 		neigh_rq_count = 0;
1073 	}
1074 
1075 	/* pay attention to not get a value bigger than 100 % */
1076 	if (orig_eq_count > neigh_rq_count)
1077 		total_count = neigh_rq_count;
1078 	else
1079 		total_count = orig_eq_count;
1080 
1081 	/* if we have too few packets (too less data) we set tq_own to zero
1082 	 * if we receive too few packets it is not considered bidirectional
1083 	 */
1084 	if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
1085 	    neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
1086 		tq_own = 0;
1087 	else
1088 		/* neigh_node->real_packet_count is never zero as we
1089 		 * only purge old information when getting new
1090 		 * information
1091 		 */
1092 		tq_own = (BATADV_TQ_MAX_VALUE * total_count) /	neigh_rq_count;
1093 
1094 	/* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
1095 	 * affect the nearly-symmetric links only a little, but
1096 	 * punishes asymmetric links more.  This will give a value
1097 	 * between 0 and TQ_MAX_VALUE
1098 	 */
1099 	neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
1100 	neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
1101 	neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
1102 			    BATADV_TQ_LOCAL_WINDOW_SIZE *
1103 			    BATADV_TQ_LOCAL_WINDOW_SIZE;
1104 	inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
1105 	inv_asym_penalty /= neigh_rq_max_cube;
1106 	tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
1107 
1108 	/* penalize if the OGM is forwarded on the same interface. WiFi
1109 	 * interfaces and other half duplex devices suffer from throughput
1110 	 * drops as they can't send and receive at the same time.
1111 	 */
1112 	tq_iface_penalty = BATADV_TQ_MAX_VALUE;
1113 	if (if_outgoing && if_incoming == if_outgoing &&
1114 	    batadv_is_wifi_hardif(if_outgoing))
1115 		tq_iface_penalty = batadv_hop_penalty(BATADV_TQ_MAX_VALUE,
1116 						      bat_priv);
1117 
1118 	combined_tq = batadv_ogm_packet->tq *
1119 		      tq_own *
1120 		      tq_asym_penalty *
1121 		      tq_iface_penalty;
1122 	combined_tq /= BATADV_TQ_MAX_VALUE *
1123 		       BATADV_TQ_MAX_VALUE *
1124 		       BATADV_TQ_MAX_VALUE;
1125 	batadv_ogm_packet->tq = combined_tq;
1126 
1127 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1128 		   "bidirectional: orig = %pM neigh = %pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, iface_penalty: %3i, total tq: %3i, if_incoming = %s, if_outgoing = %s\n",
1129 		   orig_node->orig, orig_neigh_node->orig, total_count,
1130 		   neigh_rq_count, tq_own, tq_asym_penalty, tq_iface_penalty,
1131 		   batadv_ogm_packet->tq, if_incoming->net_dev->name,
1132 		   if_outgoing ? if_outgoing->net_dev->name : "DEFAULT");
1133 
1134 	/* if link has the minimum required transmission quality
1135 	 * consider it bidirectional
1136 	 */
1137 	if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
1138 		ret = true;
1139 
1140 out:
1141 	if (neigh_node)
1142 		batadv_neigh_node_put(neigh_node);
1143 	return ret;
1144 }
1145 
1146 /**
1147  * batadv_iv_ogm_update_seqnos() -  process a batman packet for all interfaces,
1148  *  adjust the sequence number and find out whether it is a duplicate
1149  * @ethhdr: ethernet header of the packet
1150  * @batadv_ogm_packet: OGM packet to be considered
1151  * @if_incoming: interface on which the OGM packet was received
1152  * @if_outgoing: interface for which the retransmission should be considered
1153  *
1154  * Return: duplicate status as enum batadv_dup_status
1155  */
1156 static enum batadv_dup_status
1157 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
1158 			    const struct batadv_ogm_packet *batadv_ogm_packet,
1159 			    const struct batadv_hard_iface *if_incoming,
1160 			    struct batadv_hard_iface *if_outgoing)
1161 {
1162 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1163 	struct batadv_orig_node *orig_node;
1164 	struct batadv_orig_ifinfo *orig_ifinfo = NULL;
1165 	struct batadv_neigh_node *neigh_node;
1166 	struct batadv_neigh_ifinfo *neigh_ifinfo;
1167 	bool is_dup;
1168 	s32 seq_diff;
1169 	bool need_update = false;
1170 	int set_mark;
1171 	enum batadv_dup_status ret = BATADV_NO_DUP;
1172 	u32 seqno = ntohl(batadv_ogm_packet->seqno);
1173 	u8 *neigh_addr;
1174 	u8 packet_count;
1175 	unsigned long *bitmap;
1176 
1177 	orig_node = batadv_iv_ogm_orig_get(bat_priv, batadv_ogm_packet->orig);
1178 	if (!orig_node)
1179 		return BATADV_NO_DUP;
1180 
1181 	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1182 	if (WARN_ON(!orig_ifinfo)) {
1183 		batadv_orig_node_put(orig_node);
1184 		return 0;
1185 	}
1186 
1187 	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1188 	seq_diff = seqno - orig_ifinfo->last_real_seqno;
1189 
1190 	/* signalize caller that the packet is to be dropped. */
1191 	if (!hlist_empty(&orig_node->neigh_list) &&
1192 	    batadv_window_protected(bat_priv, seq_diff,
1193 				    BATADV_TQ_LOCAL_WINDOW_SIZE,
1194 				    &orig_ifinfo->batman_seqno_reset, NULL)) {
1195 		ret = BATADV_PROTECTED;
1196 		goto out;
1197 	}
1198 
1199 	rcu_read_lock();
1200 	hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1201 		neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node,
1202 						       if_outgoing);
1203 		if (!neigh_ifinfo)
1204 			continue;
1205 
1206 		neigh_addr = neigh_node->addr;
1207 		is_dup = batadv_test_bit(neigh_ifinfo->bat_iv.real_bits,
1208 					 orig_ifinfo->last_real_seqno,
1209 					 seqno);
1210 
1211 		if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
1212 		    neigh_node->if_incoming == if_incoming) {
1213 			set_mark = 1;
1214 			if (is_dup)
1215 				ret = BATADV_NEIGH_DUP;
1216 		} else {
1217 			set_mark = 0;
1218 			if (is_dup && ret != BATADV_NEIGH_DUP)
1219 				ret = BATADV_ORIG_DUP;
1220 		}
1221 
1222 		/* if the window moved, set the update flag. */
1223 		bitmap = neigh_ifinfo->bat_iv.real_bits;
1224 		need_update |= batadv_bit_get_packet(bat_priv, bitmap,
1225 						     seq_diff, set_mark);
1226 
1227 		packet_count = bitmap_weight(bitmap,
1228 					     BATADV_TQ_LOCAL_WINDOW_SIZE);
1229 		neigh_ifinfo->bat_iv.real_packet_count = packet_count;
1230 		batadv_neigh_ifinfo_put(neigh_ifinfo);
1231 	}
1232 	rcu_read_unlock();
1233 
1234 	if (need_update) {
1235 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1236 			   "%s updating last_seqno: old %u, new %u\n",
1237 			   if_outgoing ? if_outgoing->net_dev->name : "DEFAULT",
1238 			   orig_ifinfo->last_real_seqno, seqno);
1239 		orig_ifinfo->last_real_seqno = seqno;
1240 	}
1241 
1242 out:
1243 	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1244 	batadv_orig_node_put(orig_node);
1245 	batadv_orig_ifinfo_put(orig_ifinfo);
1246 	return ret;
1247 }
1248 
1249 /**
1250  * batadv_iv_ogm_process_per_outif() - process a batman iv OGM for an outgoing
1251  *  interface
1252  * @skb: the skb containing the OGM
1253  * @ogm_offset: offset from skb->data to start of ogm header
1254  * @orig_node: the (cached) orig node for the originator of this OGM
1255  * @if_incoming: the interface where this packet was received
1256  * @if_outgoing: the interface for which the packet should be considered
1257  */
1258 static void
1259 batadv_iv_ogm_process_per_outif(const struct sk_buff *skb, int ogm_offset,
1260 				struct batadv_orig_node *orig_node,
1261 				struct batadv_hard_iface *if_incoming,
1262 				struct batadv_hard_iface *if_outgoing)
1263 {
1264 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1265 	struct batadv_hardif_neigh_node *hardif_neigh = NULL;
1266 	struct batadv_neigh_node *router = NULL;
1267 	struct batadv_neigh_node *router_router = NULL;
1268 	struct batadv_orig_node *orig_neigh_node;
1269 	struct batadv_orig_ifinfo *orig_ifinfo;
1270 	struct batadv_neigh_node *orig_neigh_router = NULL;
1271 	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
1272 	struct batadv_ogm_packet *ogm_packet;
1273 	enum batadv_dup_status dup_status;
1274 	bool is_from_best_next_hop = false;
1275 	bool is_single_hop_neigh = false;
1276 	bool sameseq, similar_ttl;
1277 	struct sk_buff *skb_priv;
1278 	struct ethhdr *ethhdr;
1279 	u8 *prev_sender;
1280 	bool is_bidirect;
1281 
1282 	/* create a private copy of the skb, as some functions change tq value
1283 	 * and/or flags.
1284 	 */
1285 	skb_priv = skb_copy(skb, GFP_ATOMIC);
1286 	if (!skb_priv)
1287 		return;
1288 
1289 	ethhdr = eth_hdr(skb_priv);
1290 	ogm_packet = (struct batadv_ogm_packet *)(skb_priv->data + ogm_offset);
1291 
1292 	dup_status = batadv_iv_ogm_update_seqnos(ethhdr, ogm_packet,
1293 						 if_incoming, if_outgoing);
1294 	if (batadv_compare_eth(ethhdr->h_source, ogm_packet->orig))
1295 		is_single_hop_neigh = true;
1296 
1297 	if (dup_status == BATADV_PROTECTED) {
1298 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1299 			   "Drop packet: packet within seqno protection time (sender: %pM)\n",
1300 			   ethhdr->h_source);
1301 		goto out;
1302 	}
1303 
1304 	if (ogm_packet->tq == 0) {
1305 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1306 			   "Drop packet: originator packet with tq equal 0\n");
1307 		goto out;
1308 	}
1309 
1310 	if (is_single_hop_neigh) {
1311 		hardif_neigh = batadv_hardif_neigh_get(if_incoming,
1312 						       ethhdr->h_source);
1313 		if (hardif_neigh)
1314 			hardif_neigh->last_seen = jiffies;
1315 	}
1316 
1317 	router = batadv_orig_router_get(orig_node, if_outgoing);
1318 	if (router) {
1319 		router_router = batadv_orig_router_get(router->orig_node,
1320 						       if_outgoing);
1321 		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
1322 	}
1323 
1324 	if ((router_ifinfo && router_ifinfo->bat_iv.tq_avg != 0) &&
1325 	    (batadv_compare_eth(router->addr, ethhdr->h_source)))
1326 		is_from_best_next_hop = true;
1327 
1328 	prev_sender = ogm_packet->prev_sender;
1329 	/* avoid temporary routing loops */
1330 	if (router && router_router &&
1331 	    (batadv_compare_eth(router->addr, prev_sender)) &&
1332 	    !(batadv_compare_eth(ogm_packet->orig, prev_sender)) &&
1333 	    (batadv_compare_eth(router->addr, router_router->addr))) {
1334 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1335 			   "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1336 			   ethhdr->h_source);
1337 		goto out;
1338 	}
1339 
1340 	if (if_outgoing == BATADV_IF_DEFAULT)
1341 		batadv_tvlv_ogm_receive(bat_priv, ogm_packet, orig_node);
1342 
1343 	/* if sender is a direct neighbor the sender mac equals
1344 	 * originator mac
1345 	 */
1346 	if (is_single_hop_neigh)
1347 		orig_neigh_node = orig_node;
1348 	else
1349 		orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1350 							 ethhdr->h_source);
1351 
1352 	if (!orig_neigh_node)
1353 		goto out;
1354 
1355 	/* Update nc_nodes of the originator */
1356 	batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
1357 				 ogm_packet, is_single_hop_neigh);
1358 
1359 	orig_neigh_router = batadv_orig_router_get(orig_neigh_node,
1360 						   if_outgoing);
1361 
1362 	/* drop packet if sender is not a direct neighbor and if we
1363 	 * don't route towards it
1364 	 */
1365 	if (!is_single_hop_neigh && !orig_neigh_router) {
1366 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1367 			   "Drop packet: OGM via unknown neighbor!\n");
1368 		goto out_neigh;
1369 	}
1370 
1371 	is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1372 					    ogm_packet, if_incoming,
1373 					    if_outgoing);
1374 
1375 	/* update ranking if it is not a duplicate or has the same
1376 	 * seqno and similar ttl as the non-duplicate
1377 	 */
1378 	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
1379 	if (!orig_ifinfo)
1380 		goto out_neigh;
1381 
1382 	sameseq = orig_ifinfo->last_real_seqno == ntohl(ogm_packet->seqno);
1383 	similar_ttl = (orig_ifinfo->last_ttl - 3) <= ogm_packet->ttl;
1384 
1385 	if (is_bidirect && (dup_status == BATADV_NO_DUP ||
1386 			    (sameseq && similar_ttl))) {
1387 		batadv_iv_ogm_orig_update(bat_priv, orig_node,
1388 					  orig_ifinfo, ethhdr,
1389 					  ogm_packet, if_incoming,
1390 					  if_outgoing, dup_status);
1391 	}
1392 	batadv_orig_ifinfo_put(orig_ifinfo);
1393 
1394 	/* only forward for specific interface, not for the default one. */
1395 	if (if_outgoing == BATADV_IF_DEFAULT)
1396 		goto out_neigh;
1397 
1398 	/* is single hop (direct) neighbor */
1399 	if (is_single_hop_neigh) {
1400 		/* OGMs from secondary interfaces should only scheduled once
1401 		 * per interface where it has been received, not multiple times
1402 		 */
1403 		if (ogm_packet->ttl <= 2 &&
1404 		    if_incoming != if_outgoing) {
1405 			batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1406 				   "Drop packet: OGM from secondary interface and wrong outgoing interface\n");
1407 			goto out_neigh;
1408 		}
1409 		/* mark direct link on incoming interface */
1410 		batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1411 				      is_single_hop_neigh,
1412 				      is_from_best_next_hop, if_incoming,
1413 				      if_outgoing);
1414 
1415 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1416 			   "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1417 		goto out_neigh;
1418 	}
1419 
1420 	/* multihop originator */
1421 	if (!is_bidirect) {
1422 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1423 			   "Drop packet: not received via bidirectional link\n");
1424 		goto out_neigh;
1425 	}
1426 
1427 	if (dup_status == BATADV_NEIGH_DUP) {
1428 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1429 			   "Drop packet: duplicate packet received\n");
1430 		goto out_neigh;
1431 	}
1432 
1433 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1434 		   "Forwarding packet: rebroadcast originator packet\n");
1435 	batadv_iv_ogm_forward(orig_node, ethhdr, ogm_packet,
1436 			      is_single_hop_neigh, is_from_best_next_hop,
1437 			      if_incoming, if_outgoing);
1438 
1439 out_neigh:
1440 	if (orig_neigh_node && !is_single_hop_neigh)
1441 		batadv_orig_node_put(orig_neigh_node);
1442 out:
1443 	if (router_ifinfo)
1444 		batadv_neigh_ifinfo_put(router_ifinfo);
1445 	if (router)
1446 		batadv_neigh_node_put(router);
1447 	if (router_router)
1448 		batadv_neigh_node_put(router_router);
1449 	if (orig_neigh_router)
1450 		batadv_neigh_node_put(orig_neigh_router);
1451 	if (hardif_neigh)
1452 		batadv_hardif_neigh_put(hardif_neigh);
1453 
1454 	consume_skb(skb_priv);
1455 }
1456 
1457 /**
1458  * batadv_iv_ogm_process_reply() - Check OGM for direct reply and process it
1459  * @ogm_packet: rebroadcast OGM packet to process
1460  * @if_incoming: the interface where this packet was received
1461  * @orig_node: originator which reproadcasted the OGMs
1462  * @if_incoming_seqno: OGM sequence number when rebroadcast was received
1463  */
1464 static void batadv_iv_ogm_process_reply(struct batadv_ogm_packet *ogm_packet,
1465 					struct batadv_hard_iface *if_incoming,
1466 					struct batadv_orig_node *orig_node,
1467 					u32 if_incoming_seqno)
1468 {
1469 	struct batadv_orig_ifinfo *orig_ifinfo;
1470 	s32 bit_pos;
1471 	u8 *weight;
1472 
1473 	/* neighbor has to indicate direct link and it has to
1474 	 * come via the corresponding interface
1475 	 */
1476 	if (!(ogm_packet->flags & BATADV_DIRECTLINK))
1477 		return;
1478 
1479 	if (!batadv_compare_eth(if_incoming->net_dev->dev_addr,
1480 				ogm_packet->orig))
1481 		return;
1482 
1483 	orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_incoming);
1484 	if (!orig_ifinfo)
1485 		return;
1486 
1487 	/* save packet seqno for bidirectional check */
1488 	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1489 	bit_pos = if_incoming_seqno - 2;
1490 	bit_pos -= ntohl(ogm_packet->seqno);
1491 	batadv_set_bit(orig_ifinfo->bat_iv.bcast_own, bit_pos);
1492 	weight = &orig_ifinfo->bat_iv.bcast_own_sum;
1493 	*weight = bitmap_weight(orig_ifinfo->bat_iv.bcast_own,
1494 				BATADV_TQ_LOCAL_WINDOW_SIZE);
1495 	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
1496 
1497 	batadv_orig_ifinfo_put(orig_ifinfo);
1498 }
1499 
1500 /**
1501  * batadv_iv_ogm_process() - process an incoming batman iv OGM
1502  * @skb: the skb containing the OGM
1503  * @ogm_offset: offset to the OGM which should be processed (for aggregates)
1504  * @if_incoming: the interface where this packet was receved
1505  */
1506 static void batadv_iv_ogm_process(const struct sk_buff *skb, int ogm_offset,
1507 				  struct batadv_hard_iface *if_incoming)
1508 {
1509 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1510 	struct batadv_orig_node *orig_neigh_node, *orig_node;
1511 	struct batadv_hard_iface *hard_iface;
1512 	struct batadv_ogm_packet *ogm_packet;
1513 	u32 if_incoming_seqno;
1514 	bool has_directlink_flag;
1515 	struct ethhdr *ethhdr;
1516 	bool is_my_oldorig = false;
1517 	bool is_my_addr = false;
1518 	bool is_my_orig = false;
1519 
1520 	ogm_packet = (struct batadv_ogm_packet *)(skb->data + ogm_offset);
1521 	ethhdr = eth_hdr(skb);
1522 
1523 	/* Silently drop when the batman packet is actually not a
1524 	 * correct packet.
1525 	 *
1526 	 * This might happen if a packet is padded (e.g. Ethernet has a
1527 	 * minimum frame length of 64 byte) and the aggregation interprets
1528 	 * it as an additional length.
1529 	 *
1530 	 * TODO: A more sane solution would be to have a bit in the
1531 	 * batadv_ogm_packet to detect whether the packet is the last
1532 	 * packet in an aggregation.  Here we expect that the padding
1533 	 * is always zero (or not 0x01)
1534 	 */
1535 	if (ogm_packet->packet_type != BATADV_IV_OGM)
1536 		return;
1537 
1538 	/* could be changed by schedule_own_packet() */
1539 	if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1540 
1541 	if (ogm_packet->flags & BATADV_DIRECTLINK)
1542 		has_directlink_flag = true;
1543 	else
1544 		has_directlink_flag = false;
1545 
1546 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1547 		   "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, tq %d, TTL %d, V %d, IDF %d)\n",
1548 		   ethhdr->h_source, if_incoming->net_dev->name,
1549 		   if_incoming->net_dev->dev_addr, ogm_packet->orig,
1550 		   ogm_packet->prev_sender, ntohl(ogm_packet->seqno),
1551 		   ogm_packet->tq, ogm_packet->ttl,
1552 		   ogm_packet->version, has_directlink_flag);
1553 
1554 	rcu_read_lock();
1555 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1556 		if (hard_iface->if_status != BATADV_IF_ACTIVE)
1557 			continue;
1558 
1559 		if (hard_iface->soft_iface != if_incoming->soft_iface)
1560 			continue;
1561 
1562 		if (batadv_compare_eth(ethhdr->h_source,
1563 				       hard_iface->net_dev->dev_addr))
1564 			is_my_addr = true;
1565 
1566 		if (batadv_compare_eth(ogm_packet->orig,
1567 				       hard_iface->net_dev->dev_addr))
1568 			is_my_orig = true;
1569 
1570 		if (batadv_compare_eth(ogm_packet->prev_sender,
1571 				       hard_iface->net_dev->dev_addr))
1572 			is_my_oldorig = true;
1573 	}
1574 	rcu_read_unlock();
1575 
1576 	if (is_my_addr) {
1577 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1578 			   "Drop packet: received my own broadcast (sender: %pM)\n",
1579 			   ethhdr->h_source);
1580 		return;
1581 	}
1582 
1583 	if (is_my_orig) {
1584 		orig_neigh_node = batadv_iv_ogm_orig_get(bat_priv,
1585 							 ethhdr->h_source);
1586 		if (!orig_neigh_node)
1587 			return;
1588 
1589 		batadv_iv_ogm_process_reply(ogm_packet, if_incoming,
1590 					    orig_neigh_node, if_incoming_seqno);
1591 
1592 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1593 			   "Drop packet: originator packet from myself (via neighbor)\n");
1594 		batadv_orig_node_put(orig_neigh_node);
1595 		return;
1596 	}
1597 
1598 	if (is_my_oldorig) {
1599 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1600 			   "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1601 			   ethhdr->h_source);
1602 		return;
1603 	}
1604 
1605 	if (ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1606 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1607 			   "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1608 			   ethhdr->h_source);
1609 		return;
1610 	}
1611 
1612 	orig_node = batadv_iv_ogm_orig_get(bat_priv, ogm_packet->orig);
1613 	if (!orig_node)
1614 		return;
1615 
1616 	batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1617 					if_incoming, BATADV_IF_DEFAULT);
1618 
1619 	rcu_read_lock();
1620 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1621 		if (hard_iface->if_status != BATADV_IF_ACTIVE)
1622 			continue;
1623 
1624 		if (hard_iface->soft_iface != bat_priv->soft_iface)
1625 			continue;
1626 
1627 		if (!kref_get_unless_zero(&hard_iface->refcount))
1628 			continue;
1629 
1630 		batadv_iv_ogm_process_per_outif(skb, ogm_offset, orig_node,
1631 						if_incoming, hard_iface);
1632 
1633 		batadv_hardif_put(hard_iface);
1634 	}
1635 	rcu_read_unlock();
1636 
1637 	batadv_orig_node_put(orig_node);
1638 }
1639 
1640 static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
1641 {
1642 	struct delayed_work *delayed_work;
1643 	struct batadv_forw_packet *forw_packet;
1644 	struct batadv_priv *bat_priv;
1645 	bool dropped = false;
1646 
1647 	delayed_work = to_delayed_work(work);
1648 	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
1649 				   delayed_work);
1650 	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
1651 
1652 	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
1653 		dropped = true;
1654 		goto out;
1655 	}
1656 
1657 	batadv_iv_ogm_emit(forw_packet);
1658 
1659 	/* we have to have at least one packet in the queue to determine the
1660 	 * queues wake up time unless we are shutting down.
1661 	 *
1662 	 * only re-schedule if this is the "original" copy, e.g. the OGM of the
1663 	 * primary interface should only be rescheduled once per period, but
1664 	 * this function will be called for the forw_packet instances of the
1665 	 * other secondary interfaces as well.
1666 	 */
1667 	if (forw_packet->own &&
1668 	    forw_packet->if_incoming == forw_packet->if_outgoing)
1669 		batadv_iv_ogm_schedule(forw_packet->if_incoming);
1670 
1671 out:
1672 	/* do we get something for free()? */
1673 	if (batadv_forw_packet_steal(forw_packet,
1674 				     &bat_priv->forw_bat_list_lock))
1675 		batadv_forw_packet_free(forw_packet, dropped);
1676 }
1677 
1678 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1679 				 struct batadv_hard_iface *if_incoming)
1680 {
1681 	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1682 	struct batadv_ogm_packet *ogm_packet;
1683 	u8 *packet_pos;
1684 	int ogm_offset;
1685 	bool res;
1686 	int ret = NET_RX_DROP;
1687 
1688 	res = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1689 	if (!res)
1690 		goto free_skb;
1691 
1692 	/* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1693 	 * that does not have B.A.T.M.A.N. IV enabled ?
1694 	 */
1695 	if (bat_priv->algo_ops->iface.enable != batadv_iv_ogm_iface_enable)
1696 		goto free_skb;
1697 
1698 	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1699 	batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1700 			   skb->len + ETH_HLEN);
1701 
1702 	ogm_offset = 0;
1703 	ogm_packet = (struct batadv_ogm_packet *)skb->data;
1704 
1705 	/* unpack the aggregated packets and process them one by one */
1706 	while (batadv_iv_ogm_aggr_packet(ogm_offset, skb_headlen(skb),
1707 					 ogm_packet->tvlv_len)) {
1708 		batadv_iv_ogm_process(skb, ogm_offset, if_incoming);
1709 
1710 		ogm_offset += BATADV_OGM_HLEN;
1711 		ogm_offset += ntohs(ogm_packet->tvlv_len);
1712 
1713 		packet_pos = skb->data + ogm_offset;
1714 		ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1715 	}
1716 
1717 	ret = NET_RX_SUCCESS;
1718 
1719 free_skb:
1720 	if (ret == NET_RX_SUCCESS)
1721 		consume_skb(skb);
1722 	else
1723 		kfree_skb(skb);
1724 
1725 	return ret;
1726 }
1727 
1728 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
1729 /**
1730  * batadv_iv_ogm_orig_print_neigh() - print neighbors for the originator table
1731  * @orig_node: the orig_node for which the neighbors are printed
1732  * @if_outgoing: outgoing interface for these entries
1733  * @seq: debugfs table seq_file struct
1734  *
1735  * Must be called while holding an rcu lock.
1736  */
1737 static void
1738 batadv_iv_ogm_orig_print_neigh(struct batadv_orig_node *orig_node,
1739 			       struct batadv_hard_iface *if_outgoing,
1740 			       struct seq_file *seq)
1741 {
1742 	struct batadv_neigh_node *neigh_node;
1743 	struct batadv_neigh_ifinfo *n_ifinfo;
1744 
1745 	hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1746 		n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
1747 		if (!n_ifinfo)
1748 			continue;
1749 
1750 		seq_printf(seq, " %pM (%3i)",
1751 			   neigh_node->addr,
1752 			   n_ifinfo->bat_iv.tq_avg);
1753 
1754 		batadv_neigh_ifinfo_put(n_ifinfo);
1755 	}
1756 }
1757 
1758 /**
1759  * batadv_iv_ogm_orig_print() - print the originator table
1760  * @bat_priv: the bat priv with all the soft interface information
1761  * @seq: debugfs table seq_file struct
1762  * @if_outgoing: the outgoing interface for which this should be printed
1763  */
1764 static void batadv_iv_ogm_orig_print(struct batadv_priv *bat_priv,
1765 				     struct seq_file *seq,
1766 				     struct batadv_hard_iface *if_outgoing)
1767 {
1768 	struct batadv_neigh_node *neigh_node;
1769 	struct batadv_hashtable *hash = bat_priv->orig_hash;
1770 	int last_seen_msecs, last_seen_secs;
1771 	struct batadv_orig_node *orig_node;
1772 	struct batadv_neigh_ifinfo *n_ifinfo;
1773 	unsigned long last_seen_jiffies;
1774 	struct hlist_head *head;
1775 	int batman_count = 0;
1776 	u32 i;
1777 
1778 	seq_puts(seq,
1779 		 "  Originator      last-seen (#/255)           Nexthop [outgoingIF]:   Potential nexthops ...\n");
1780 
1781 	for (i = 0; i < hash->size; i++) {
1782 		head = &hash->table[i];
1783 
1784 		rcu_read_lock();
1785 		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
1786 			neigh_node = batadv_orig_router_get(orig_node,
1787 							    if_outgoing);
1788 			if (!neigh_node)
1789 				continue;
1790 
1791 			n_ifinfo = batadv_neigh_ifinfo_get(neigh_node,
1792 							   if_outgoing);
1793 			if (!n_ifinfo)
1794 				goto next;
1795 
1796 			if (n_ifinfo->bat_iv.tq_avg == 0)
1797 				goto next;
1798 
1799 			last_seen_jiffies = jiffies - orig_node->last_seen;
1800 			last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
1801 			last_seen_secs = last_seen_msecs / 1000;
1802 			last_seen_msecs = last_seen_msecs % 1000;
1803 
1804 			seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
1805 				   orig_node->orig, last_seen_secs,
1806 				   last_seen_msecs, n_ifinfo->bat_iv.tq_avg,
1807 				   neigh_node->addr,
1808 				   neigh_node->if_incoming->net_dev->name);
1809 
1810 			batadv_iv_ogm_orig_print_neigh(orig_node, if_outgoing,
1811 						       seq);
1812 			seq_putc(seq, '\n');
1813 			batman_count++;
1814 
1815 next:
1816 			batadv_neigh_node_put(neigh_node);
1817 			if (n_ifinfo)
1818 				batadv_neigh_ifinfo_put(n_ifinfo);
1819 		}
1820 		rcu_read_unlock();
1821 	}
1822 
1823 	if (batman_count == 0)
1824 		seq_puts(seq, "No batman nodes in range ...\n");
1825 }
1826 #endif
1827 
1828 /**
1829  * batadv_iv_ogm_neigh_get_tq_avg() - Get the TQ average for a neighbour on a
1830  *  given outgoing interface.
1831  * @neigh_node: Neighbour of interest
1832  * @if_outgoing: Outgoing interface of interest
1833  * @tq_avg: Pointer of where to store the TQ average
1834  *
1835  * Return: False if no average TQ available, otherwise true.
1836  */
1837 static bool
1838 batadv_iv_ogm_neigh_get_tq_avg(struct batadv_neigh_node *neigh_node,
1839 			       struct batadv_hard_iface *if_outgoing,
1840 			       u8 *tq_avg)
1841 {
1842 	struct batadv_neigh_ifinfo *n_ifinfo;
1843 
1844 	n_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
1845 	if (!n_ifinfo)
1846 		return false;
1847 
1848 	*tq_avg = n_ifinfo->bat_iv.tq_avg;
1849 	batadv_neigh_ifinfo_put(n_ifinfo);
1850 
1851 	return true;
1852 }
1853 
1854 /**
1855  * batadv_iv_ogm_orig_dump_subentry() - Dump an originator subentry into a
1856  *  message
1857  * @msg: Netlink message to dump into
1858  * @portid: Port making netlink request
1859  * @seq: Sequence number of netlink message
1860  * @bat_priv: The bat priv with all the soft interface information
1861  * @if_outgoing: Limit dump to entries with this outgoing interface
1862  * @orig_node: Originator to dump
1863  * @neigh_node: Single hops neighbour
1864  * @best: Is the best originator
1865  *
1866  * Return: Error code, or 0 on success
1867  */
1868 static int
1869 batadv_iv_ogm_orig_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
1870 				 struct batadv_priv *bat_priv,
1871 				 struct batadv_hard_iface *if_outgoing,
1872 				 struct batadv_orig_node *orig_node,
1873 				 struct batadv_neigh_node *neigh_node,
1874 				 bool best)
1875 {
1876 	void *hdr;
1877 	u8 tq_avg;
1878 	unsigned int last_seen_msecs;
1879 
1880 	last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_seen);
1881 
1882 	if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node, if_outgoing, &tq_avg))
1883 		return 0;
1884 
1885 	if (if_outgoing != BATADV_IF_DEFAULT &&
1886 	    if_outgoing != neigh_node->if_incoming)
1887 		return 0;
1888 
1889 	hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
1890 			  NLM_F_MULTI, BATADV_CMD_GET_ORIGINATORS);
1891 	if (!hdr)
1892 		return -ENOBUFS;
1893 
1894 	if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
1895 		    orig_node->orig) ||
1896 	    nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
1897 		    neigh_node->addr) ||
1898 	    nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
1899 			neigh_node->if_incoming->net_dev->ifindex) ||
1900 	    nla_put_u8(msg, BATADV_ATTR_TQ, tq_avg) ||
1901 	    nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
1902 			last_seen_msecs))
1903 		goto nla_put_failure;
1904 
1905 	if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
1906 		goto nla_put_failure;
1907 
1908 	genlmsg_end(msg, hdr);
1909 	return 0;
1910 
1911  nla_put_failure:
1912 	genlmsg_cancel(msg, hdr);
1913 	return -EMSGSIZE;
1914 }
1915 
1916 /**
1917  * batadv_iv_ogm_orig_dump_entry() - Dump an originator entry into a message
1918  * @msg: Netlink message to dump into
1919  * @portid: Port making netlink request
1920  * @seq: Sequence number of netlink message
1921  * @bat_priv: The bat priv with all the soft interface information
1922  * @if_outgoing: Limit dump to entries with this outgoing interface
1923  * @orig_node: Originator to dump
1924  * @sub_s: Number of sub entries to skip
1925  *
1926  * This function assumes the caller holds rcu_read_lock().
1927  *
1928  * Return: Error code, or 0 on success
1929  */
1930 static int
1931 batadv_iv_ogm_orig_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
1932 			      struct batadv_priv *bat_priv,
1933 			      struct batadv_hard_iface *if_outgoing,
1934 			      struct batadv_orig_node *orig_node, int *sub_s)
1935 {
1936 	struct batadv_neigh_node *neigh_node_best;
1937 	struct batadv_neigh_node *neigh_node;
1938 	int sub = 0;
1939 	bool best;
1940 	u8 tq_avg_best;
1941 
1942 	neigh_node_best = batadv_orig_router_get(orig_node, if_outgoing);
1943 	if (!neigh_node_best)
1944 		goto out;
1945 
1946 	if (!batadv_iv_ogm_neigh_get_tq_avg(neigh_node_best, if_outgoing,
1947 					    &tq_avg_best))
1948 		goto out;
1949 
1950 	if (tq_avg_best == 0)
1951 		goto out;
1952 
1953 	hlist_for_each_entry_rcu(neigh_node, &orig_node->neigh_list, list) {
1954 		if (sub++ < *sub_s)
1955 			continue;
1956 
1957 		best = (neigh_node == neigh_node_best);
1958 
1959 		if (batadv_iv_ogm_orig_dump_subentry(msg, portid, seq,
1960 						     bat_priv, if_outgoing,
1961 						     orig_node, neigh_node,
1962 						     best)) {
1963 			batadv_neigh_node_put(neigh_node_best);
1964 
1965 			*sub_s = sub - 1;
1966 			return -EMSGSIZE;
1967 		}
1968 	}
1969 
1970  out:
1971 	if (neigh_node_best)
1972 		batadv_neigh_node_put(neigh_node_best);
1973 
1974 	*sub_s = 0;
1975 	return 0;
1976 }
1977 
1978 /**
1979  * batadv_iv_ogm_orig_dump_bucket() - Dump an originator bucket into a
1980  *  message
1981  * @msg: Netlink message to dump into
1982  * @portid: Port making netlink request
1983  * @seq: Sequence number of netlink message
1984  * @bat_priv: The bat priv with all the soft interface information
1985  * @if_outgoing: Limit dump to entries with this outgoing interface
1986  * @head: Bucket to be dumped
1987  * @idx_s: Number of entries to be skipped
1988  * @sub: Number of sub entries to be skipped
1989  *
1990  * Return: Error code, or 0 on success
1991  */
1992 static int
1993 batadv_iv_ogm_orig_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
1994 			       struct batadv_priv *bat_priv,
1995 			       struct batadv_hard_iface *if_outgoing,
1996 			       struct hlist_head *head, int *idx_s, int *sub)
1997 {
1998 	struct batadv_orig_node *orig_node;
1999 	int idx = 0;
2000 
2001 	rcu_read_lock();
2002 	hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
2003 		if (idx++ < *idx_s)
2004 			continue;
2005 
2006 		if (batadv_iv_ogm_orig_dump_entry(msg, portid, seq, bat_priv,
2007 						  if_outgoing, orig_node,
2008 						  sub)) {
2009 			rcu_read_unlock();
2010 			*idx_s = idx - 1;
2011 			return -EMSGSIZE;
2012 		}
2013 	}
2014 	rcu_read_unlock();
2015 
2016 	*idx_s = 0;
2017 	*sub = 0;
2018 	return 0;
2019 }
2020 
2021 /**
2022  * batadv_iv_ogm_orig_dump() - Dump the originators into a message
2023  * @msg: Netlink message to dump into
2024  * @cb: Control block containing additional options
2025  * @bat_priv: The bat priv with all the soft interface information
2026  * @if_outgoing: Limit dump to entries with this outgoing interface
2027  */
2028 static void
2029 batadv_iv_ogm_orig_dump(struct sk_buff *msg, struct netlink_callback *cb,
2030 			struct batadv_priv *bat_priv,
2031 			struct batadv_hard_iface *if_outgoing)
2032 {
2033 	struct batadv_hashtable *hash = bat_priv->orig_hash;
2034 	struct hlist_head *head;
2035 	int bucket = cb->args[0];
2036 	int idx = cb->args[1];
2037 	int sub = cb->args[2];
2038 	int portid = NETLINK_CB(cb->skb).portid;
2039 
2040 	while (bucket < hash->size) {
2041 		head = &hash->table[bucket];
2042 
2043 		if (batadv_iv_ogm_orig_dump_bucket(msg, portid,
2044 						   cb->nlh->nlmsg_seq,
2045 						   bat_priv, if_outgoing, head,
2046 						   &idx, &sub))
2047 			break;
2048 
2049 		bucket++;
2050 	}
2051 
2052 	cb->args[0] = bucket;
2053 	cb->args[1] = idx;
2054 	cb->args[2] = sub;
2055 }
2056 
2057 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2058 /**
2059  * batadv_iv_hardif_neigh_print() - print a single hop neighbour node
2060  * @seq: neighbour table seq_file struct
2061  * @hardif_neigh: hardif neighbour information
2062  */
2063 static void
2064 batadv_iv_hardif_neigh_print(struct seq_file *seq,
2065 			     struct batadv_hardif_neigh_node *hardif_neigh)
2066 {
2067 	int last_secs, last_msecs;
2068 
2069 	last_secs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) / 1000;
2070 	last_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen) % 1000;
2071 
2072 	seq_printf(seq, "   %10s   %pM %4i.%03is\n",
2073 		   hardif_neigh->if_incoming->net_dev->name,
2074 		   hardif_neigh->addr, last_secs, last_msecs);
2075 }
2076 
2077 /**
2078  * batadv_iv_ogm_neigh_print() - print the single hop neighbour list
2079  * @bat_priv: the bat priv with all the soft interface information
2080  * @seq: neighbour table seq_file struct
2081  */
2082 static void batadv_iv_neigh_print(struct batadv_priv *bat_priv,
2083 				  struct seq_file *seq)
2084 {
2085 	struct net_device *net_dev = (struct net_device *)seq->private;
2086 	struct batadv_hardif_neigh_node *hardif_neigh;
2087 	struct batadv_hard_iface *hard_iface;
2088 	int batman_count = 0;
2089 
2090 	seq_puts(seq, "           IF        Neighbor      last-seen\n");
2091 
2092 	rcu_read_lock();
2093 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
2094 		if (hard_iface->soft_iface != net_dev)
2095 			continue;
2096 
2097 		hlist_for_each_entry_rcu(hardif_neigh,
2098 					 &hard_iface->neigh_list, list) {
2099 			batadv_iv_hardif_neigh_print(seq, hardif_neigh);
2100 			batman_count++;
2101 		}
2102 	}
2103 	rcu_read_unlock();
2104 
2105 	if (batman_count == 0)
2106 		seq_puts(seq, "No batman nodes in range ...\n");
2107 }
2108 #endif
2109 
2110 /**
2111  * batadv_iv_ogm_neigh_diff() - calculate tq difference of two neighbors
2112  * @neigh1: the first neighbor object of the comparison
2113  * @if_outgoing1: outgoing interface for the first neighbor
2114  * @neigh2: the second neighbor object of the comparison
2115  * @if_outgoing2: outgoing interface for the second neighbor
2116  * @diff: pointer to integer receiving the calculated difference
2117  *
2118  * The content of *@diff is only valid when this function returns true.
2119  * It is less, equal to or greater than 0 if the metric via neigh1 is lower,
2120  * the same as or higher than the metric via neigh2
2121  *
2122  * Return: true when the difference could be calculated, false otherwise
2123  */
2124 static bool batadv_iv_ogm_neigh_diff(struct batadv_neigh_node *neigh1,
2125 				     struct batadv_hard_iface *if_outgoing1,
2126 				     struct batadv_neigh_node *neigh2,
2127 				     struct batadv_hard_iface *if_outgoing2,
2128 				     int *diff)
2129 {
2130 	struct batadv_neigh_ifinfo *neigh1_ifinfo, *neigh2_ifinfo;
2131 	u8 tq1, tq2;
2132 	bool ret = true;
2133 
2134 	neigh1_ifinfo = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
2135 	neigh2_ifinfo = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
2136 
2137 	if (!neigh1_ifinfo || !neigh2_ifinfo) {
2138 		ret = false;
2139 		goto out;
2140 	}
2141 
2142 	tq1 = neigh1_ifinfo->bat_iv.tq_avg;
2143 	tq2 = neigh2_ifinfo->bat_iv.tq_avg;
2144 	*diff = (int)tq1 - (int)tq2;
2145 
2146 out:
2147 	if (neigh1_ifinfo)
2148 		batadv_neigh_ifinfo_put(neigh1_ifinfo);
2149 	if (neigh2_ifinfo)
2150 		batadv_neigh_ifinfo_put(neigh2_ifinfo);
2151 
2152 	return ret;
2153 }
2154 
2155 /**
2156  * batadv_iv_ogm_neigh_dump_neigh() - Dump a neighbour into a netlink message
2157  * @msg: Netlink message to dump into
2158  * @portid: Port making netlink request
2159  * @seq: Sequence number of netlink message
2160  * @hardif_neigh: Neighbour to be dumped
2161  *
2162  * Return: Error code, or 0 on success
2163  */
2164 static int
2165 batadv_iv_ogm_neigh_dump_neigh(struct sk_buff *msg, u32 portid, u32 seq,
2166 			       struct batadv_hardif_neigh_node *hardif_neigh)
2167 {
2168 	void *hdr;
2169 	unsigned int last_seen_msecs;
2170 
2171 	last_seen_msecs = jiffies_to_msecs(jiffies - hardif_neigh->last_seen);
2172 
2173 	hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
2174 			  NLM_F_MULTI, BATADV_CMD_GET_NEIGHBORS);
2175 	if (!hdr)
2176 		return -ENOBUFS;
2177 
2178 	if (nla_put(msg, BATADV_ATTR_NEIGH_ADDRESS, ETH_ALEN,
2179 		    hardif_neigh->addr) ||
2180 	    nla_put_u32(msg, BATADV_ATTR_HARD_IFINDEX,
2181 			hardif_neigh->if_incoming->net_dev->ifindex) ||
2182 	    nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS,
2183 			last_seen_msecs))
2184 		goto nla_put_failure;
2185 
2186 	genlmsg_end(msg, hdr);
2187 	return 0;
2188 
2189  nla_put_failure:
2190 	genlmsg_cancel(msg, hdr);
2191 	return -EMSGSIZE;
2192 }
2193 
2194 /**
2195  * batadv_iv_ogm_neigh_dump_hardif() - Dump the neighbours of a hard interface
2196  *  into a message
2197  * @msg: Netlink message to dump into
2198  * @portid: Port making netlink request
2199  * @seq: Sequence number of netlink message
2200  * @bat_priv: The bat priv with all the soft interface information
2201  * @hard_iface: Hard interface to dump the neighbours for
2202  * @idx_s: Number of entries to skip
2203  *
2204  * This function assumes the caller holds rcu_read_lock().
2205  *
2206  * Return: Error code, or 0 on success
2207  */
2208 static int
2209 batadv_iv_ogm_neigh_dump_hardif(struct sk_buff *msg, u32 portid, u32 seq,
2210 				struct batadv_priv *bat_priv,
2211 				struct batadv_hard_iface *hard_iface,
2212 				int *idx_s)
2213 {
2214 	struct batadv_hardif_neigh_node *hardif_neigh;
2215 	int idx = 0;
2216 
2217 	hlist_for_each_entry_rcu(hardif_neigh,
2218 				 &hard_iface->neigh_list, list) {
2219 		if (idx++ < *idx_s)
2220 			continue;
2221 
2222 		if (batadv_iv_ogm_neigh_dump_neigh(msg, portid, seq,
2223 						   hardif_neigh)) {
2224 			*idx_s = idx - 1;
2225 			return -EMSGSIZE;
2226 		}
2227 	}
2228 
2229 	*idx_s = 0;
2230 	return 0;
2231 }
2232 
2233 /**
2234  * batadv_iv_ogm_neigh_dump() - Dump the neighbours into a message
2235  * @msg: Netlink message to dump into
2236  * @cb: Control block containing additional options
2237  * @bat_priv: The bat priv with all the soft interface information
2238  * @single_hardif: Limit dump to this hard interfaace
2239  */
2240 static void
2241 batadv_iv_ogm_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb,
2242 			 struct batadv_priv *bat_priv,
2243 			 struct batadv_hard_iface *single_hardif)
2244 {
2245 	struct batadv_hard_iface *hard_iface;
2246 	int i_hardif = 0;
2247 	int i_hardif_s = cb->args[0];
2248 	int idx = cb->args[1];
2249 	int portid = NETLINK_CB(cb->skb).portid;
2250 
2251 	rcu_read_lock();
2252 	if (single_hardif) {
2253 		if (i_hardif_s == 0) {
2254 			if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2255 							    cb->nlh->nlmsg_seq,
2256 							    bat_priv,
2257 							    single_hardif,
2258 							    &idx) == 0)
2259 				i_hardif++;
2260 		}
2261 	} else {
2262 		list_for_each_entry_rcu(hard_iface, &batadv_hardif_list,
2263 					list) {
2264 			if (hard_iface->soft_iface != bat_priv->soft_iface)
2265 				continue;
2266 
2267 			if (i_hardif++ < i_hardif_s)
2268 				continue;
2269 
2270 			if (batadv_iv_ogm_neigh_dump_hardif(msg, portid,
2271 							    cb->nlh->nlmsg_seq,
2272 							    bat_priv,
2273 							    hard_iface, &idx)) {
2274 				i_hardif--;
2275 				break;
2276 			}
2277 		}
2278 	}
2279 	rcu_read_unlock();
2280 
2281 	cb->args[0] = i_hardif;
2282 	cb->args[1] = idx;
2283 }
2284 
2285 /**
2286  * batadv_iv_ogm_neigh_cmp() - compare the metrics of two neighbors
2287  * @neigh1: the first neighbor object of the comparison
2288  * @if_outgoing1: outgoing interface for the first neighbor
2289  * @neigh2: the second neighbor object of the comparison
2290  * @if_outgoing2: outgoing interface for the second neighbor
2291  *
2292  * Return: a value less, equal to or greater than 0 if the metric via neigh1 is
2293  * lower, the same as or higher than the metric via neigh2
2294  */
2295 static int batadv_iv_ogm_neigh_cmp(struct batadv_neigh_node *neigh1,
2296 				   struct batadv_hard_iface *if_outgoing1,
2297 				   struct batadv_neigh_node *neigh2,
2298 				   struct batadv_hard_iface *if_outgoing2)
2299 {
2300 	bool ret;
2301 	int diff;
2302 
2303 	ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2304 				       if_outgoing2, &diff);
2305 	if (!ret)
2306 		return 0;
2307 
2308 	return diff;
2309 }
2310 
2311 /**
2312  * batadv_iv_ogm_neigh_is_sob() - check if neigh1 is similarly good or better
2313  *  than neigh2 from the metric prospective
2314  * @neigh1: the first neighbor object of the comparison
2315  * @if_outgoing1: outgoing interface for the first neighbor
2316  * @neigh2: the second neighbor object of the comparison
2317  * @if_outgoing2: outgoing interface for the second neighbor
2318  *
2319  * Return: true if the metric via neigh1 is equally good or better than
2320  * the metric via neigh2, false otherwise.
2321  */
2322 static bool
2323 batadv_iv_ogm_neigh_is_sob(struct batadv_neigh_node *neigh1,
2324 			   struct batadv_hard_iface *if_outgoing1,
2325 			   struct batadv_neigh_node *neigh2,
2326 			   struct batadv_hard_iface *if_outgoing2)
2327 {
2328 	bool ret;
2329 	int diff;
2330 
2331 	ret = batadv_iv_ogm_neigh_diff(neigh1, if_outgoing1, neigh2,
2332 				       if_outgoing2, &diff);
2333 	if (!ret)
2334 		return false;
2335 
2336 	ret = diff > -BATADV_TQ_SIMILARITY_THRESHOLD;
2337 	return ret;
2338 }
2339 
2340 static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
2341 {
2342 	/* begin scheduling originator messages on that interface */
2343 	batadv_iv_ogm_schedule(hard_iface);
2344 }
2345 
2346 /**
2347  * batadv_iv_init_sel_class() - initialize GW selection class
2348  * @bat_priv: the bat priv with all the soft interface information
2349  */
2350 static void batadv_iv_init_sel_class(struct batadv_priv *bat_priv)
2351 {
2352 	/* set default TQ difference threshold to 20 */
2353 	atomic_set(&bat_priv->gw.sel_class, 20);
2354 }
2355 
2356 static struct batadv_gw_node *
2357 batadv_iv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
2358 {
2359 	struct batadv_neigh_node *router;
2360 	struct batadv_neigh_ifinfo *router_ifinfo;
2361 	struct batadv_gw_node *gw_node, *curr_gw = NULL;
2362 	u64 max_gw_factor = 0;
2363 	u64 tmp_gw_factor = 0;
2364 	u8 max_tq = 0;
2365 	u8 tq_avg;
2366 	struct batadv_orig_node *orig_node;
2367 
2368 	rcu_read_lock();
2369 	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
2370 		orig_node = gw_node->orig_node;
2371 		router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2372 		if (!router)
2373 			continue;
2374 
2375 		router_ifinfo = batadv_neigh_ifinfo_get(router,
2376 							BATADV_IF_DEFAULT);
2377 		if (!router_ifinfo)
2378 			goto next;
2379 
2380 		if (!kref_get_unless_zero(&gw_node->refcount))
2381 			goto next;
2382 
2383 		tq_avg = router_ifinfo->bat_iv.tq_avg;
2384 
2385 		switch (atomic_read(&bat_priv->gw.sel_class)) {
2386 		case 1: /* fast connection */
2387 			tmp_gw_factor = tq_avg * tq_avg;
2388 			tmp_gw_factor *= gw_node->bandwidth_down;
2389 			tmp_gw_factor *= 100 * 100;
2390 			tmp_gw_factor >>= 18;
2391 
2392 			if (tmp_gw_factor > max_gw_factor ||
2393 			    (tmp_gw_factor == max_gw_factor &&
2394 			     tq_avg > max_tq)) {
2395 				if (curr_gw)
2396 					batadv_gw_node_put(curr_gw);
2397 				curr_gw = gw_node;
2398 				kref_get(&curr_gw->refcount);
2399 			}
2400 			break;
2401 
2402 		default: /* 2:  stable connection (use best statistic)
2403 			  * 3:  fast-switch (use best statistic but change as
2404 			  *     soon as a better gateway appears)
2405 			  * XX: late-switch (use best statistic but change as
2406 			  *     soon as a better gateway appears which has
2407 			  *     $routing_class more tq points)
2408 			  */
2409 			if (tq_avg > max_tq) {
2410 				if (curr_gw)
2411 					batadv_gw_node_put(curr_gw);
2412 				curr_gw = gw_node;
2413 				kref_get(&curr_gw->refcount);
2414 			}
2415 			break;
2416 		}
2417 
2418 		if (tq_avg > max_tq)
2419 			max_tq = tq_avg;
2420 
2421 		if (tmp_gw_factor > max_gw_factor)
2422 			max_gw_factor = tmp_gw_factor;
2423 
2424 		batadv_gw_node_put(gw_node);
2425 
2426 next:
2427 		batadv_neigh_node_put(router);
2428 		if (router_ifinfo)
2429 			batadv_neigh_ifinfo_put(router_ifinfo);
2430 	}
2431 	rcu_read_unlock();
2432 
2433 	return curr_gw;
2434 }
2435 
2436 static bool batadv_iv_gw_is_eligible(struct batadv_priv *bat_priv,
2437 				     struct batadv_orig_node *curr_gw_orig,
2438 				     struct batadv_orig_node *orig_node)
2439 {
2440 	struct batadv_neigh_ifinfo *router_orig_ifinfo = NULL;
2441 	struct batadv_neigh_ifinfo *router_gw_ifinfo = NULL;
2442 	struct batadv_neigh_node *router_gw = NULL;
2443 	struct batadv_neigh_node *router_orig = NULL;
2444 	u8 gw_tq_avg, orig_tq_avg;
2445 	bool ret = false;
2446 
2447 	/* dynamic re-election is performed only on fast or late switch */
2448 	if (atomic_read(&bat_priv->gw.sel_class) <= 2)
2449 		return false;
2450 
2451 	router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
2452 	if (!router_gw) {
2453 		ret = true;
2454 		goto out;
2455 	}
2456 
2457 	router_gw_ifinfo = batadv_neigh_ifinfo_get(router_gw,
2458 						   BATADV_IF_DEFAULT);
2459 	if (!router_gw_ifinfo) {
2460 		ret = true;
2461 		goto out;
2462 	}
2463 
2464 	router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
2465 	if (!router_orig)
2466 		goto out;
2467 
2468 	router_orig_ifinfo = batadv_neigh_ifinfo_get(router_orig,
2469 						     BATADV_IF_DEFAULT);
2470 	if (!router_orig_ifinfo)
2471 		goto out;
2472 
2473 	gw_tq_avg = router_gw_ifinfo->bat_iv.tq_avg;
2474 	orig_tq_avg = router_orig_ifinfo->bat_iv.tq_avg;
2475 
2476 	/* the TQ value has to be better */
2477 	if (orig_tq_avg < gw_tq_avg)
2478 		goto out;
2479 
2480 	/* if the routing class is greater than 3 the value tells us how much
2481 	 * greater the TQ value of the new gateway must be
2482 	 */
2483 	if ((atomic_read(&bat_priv->gw.sel_class) > 3) &&
2484 	    (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw.sel_class)))
2485 		goto out;
2486 
2487 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
2488 		   "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
2489 		   gw_tq_avg, orig_tq_avg);
2490 
2491 	ret = true;
2492 out:
2493 	if (router_gw_ifinfo)
2494 		batadv_neigh_ifinfo_put(router_gw_ifinfo);
2495 	if (router_orig_ifinfo)
2496 		batadv_neigh_ifinfo_put(router_orig_ifinfo);
2497 	if (router_gw)
2498 		batadv_neigh_node_put(router_gw);
2499 	if (router_orig)
2500 		batadv_neigh_node_put(router_orig);
2501 
2502 	return ret;
2503 }
2504 
2505 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2506 /* fails if orig_node has no router */
2507 static int batadv_iv_gw_write_buffer_text(struct batadv_priv *bat_priv,
2508 					  struct seq_file *seq,
2509 					  const struct batadv_gw_node *gw_node)
2510 {
2511 	struct batadv_gw_node *curr_gw;
2512 	struct batadv_neigh_node *router;
2513 	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
2514 	int ret = -1;
2515 
2516 	router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
2517 	if (!router)
2518 		goto out;
2519 
2520 	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
2521 	if (!router_ifinfo)
2522 		goto out;
2523 
2524 	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
2525 
2526 	seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
2527 		   (curr_gw == gw_node ? "=>" : "  "),
2528 		   gw_node->orig_node->orig,
2529 		   router_ifinfo->bat_iv.tq_avg, router->addr,
2530 		   router->if_incoming->net_dev->name,
2531 		   gw_node->bandwidth_down / 10,
2532 		   gw_node->bandwidth_down % 10,
2533 		   gw_node->bandwidth_up / 10,
2534 		   gw_node->bandwidth_up % 10);
2535 	ret = seq_has_overflowed(seq) ? -1 : 0;
2536 
2537 	if (curr_gw)
2538 		batadv_gw_node_put(curr_gw);
2539 out:
2540 	if (router_ifinfo)
2541 		batadv_neigh_ifinfo_put(router_ifinfo);
2542 	if (router)
2543 		batadv_neigh_node_put(router);
2544 	return ret;
2545 }
2546 
2547 static void batadv_iv_gw_print(struct batadv_priv *bat_priv,
2548 			       struct seq_file *seq)
2549 {
2550 	struct batadv_gw_node *gw_node;
2551 	int gw_count = 0;
2552 
2553 	seq_puts(seq,
2554 		 "      Gateway      (#/255)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
2555 
2556 	rcu_read_lock();
2557 	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.gateway_list, list) {
2558 		/* fails if orig_node has no router */
2559 		if (batadv_iv_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
2560 			continue;
2561 
2562 		gw_count++;
2563 	}
2564 	rcu_read_unlock();
2565 
2566 	if (gw_count == 0)
2567 		seq_puts(seq, "No gateways in range ...\n");
2568 }
2569 #endif
2570 
2571 /**
2572  * batadv_iv_gw_dump_entry() - Dump a gateway into a message
2573  * @msg: Netlink message to dump into
2574  * @portid: Port making netlink request
2575  * @cb: Control block containing additional options
2576  * @bat_priv: The bat priv with all the soft interface information
2577  * @gw_node: Gateway to be dumped
2578  *
2579  * Return: Error code, or 0 on success
2580  */
2581 static int batadv_iv_gw_dump_entry(struct sk_buff *msg, u32 portid,
2582 				   struct netlink_callback *cb,
2583 				   struct batadv_priv *bat_priv,
2584 				   struct batadv_gw_node *gw_node)
2585 {
2586 	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
2587 	struct batadv_neigh_node *router;
2588 	struct batadv_gw_node *curr_gw = NULL;
2589 	int ret = 0;
2590 	void *hdr;
2591 
2592 	router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
2593 	if (!router)
2594 		goto out;
2595 
2596 	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
2597 	if (!router_ifinfo)
2598 		goto out;
2599 
2600 	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
2601 
2602 	hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
2603 			  &batadv_netlink_family, NLM_F_MULTI,
2604 			  BATADV_CMD_GET_GATEWAYS);
2605 	if (!hdr) {
2606 		ret = -ENOBUFS;
2607 		goto out;
2608 	}
2609 
2610 	genl_dump_check_consistent(cb, hdr);
2611 
2612 	ret = -EMSGSIZE;
2613 
2614 	if (curr_gw == gw_node)
2615 		if (nla_put_flag(msg, BATADV_ATTR_FLAG_BEST)) {
2616 			genlmsg_cancel(msg, hdr);
2617 			goto out;
2618 		}
2619 
2620 	if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
2621 		    gw_node->orig_node->orig) ||
2622 	    nla_put_u8(msg, BATADV_ATTR_TQ, router_ifinfo->bat_iv.tq_avg) ||
2623 	    nla_put(msg, BATADV_ATTR_ROUTER, ETH_ALEN,
2624 		    router->addr) ||
2625 	    nla_put_string(msg, BATADV_ATTR_HARD_IFNAME,
2626 			   router->if_incoming->net_dev->name) ||
2627 	    nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_DOWN,
2628 			gw_node->bandwidth_down) ||
2629 	    nla_put_u32(msg, BATADV_ATTR_BANDWIDTH_UP,
2630 			gw_node->bandwidth_up)) {
2631 		genlmsg_cancel(msg, hdr);
2632 		goto out;
2633 	}
2634 
2635 	genlmsg_end(msg, hdr);
2636 	ret = 0;
2637 
2638 out:
2639 	if (curr_gw)
2640 		batadv_gw_node_put(curr_gw);
2641 	if (router_ifinfo)
2642 		batadv_neigh_ifinfo_put(router_ifinfo);
2643 	if (router)
2644 		batadv_neigh_node_put(router);
2645 	return ret;
2646 }
2647 
2648 /**
2649  * batadv_iv_gw_dump() - Dump gateways into a message
2650  * @msg: Netlink message to dump into
2651  * @cb: Control block containing additional options
2652  * @bat_priv: The bat priv with all the soft interface information
2653  */
2654 static void batadv_iv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb,
2655 			      struct batadv_priv *bat_priv)
2656 {
2657 	int portid = NETLINK_CB(cb->skb).portid;
2658 	struct batadv_gw_node *gw_node;
2659 	int idx_skip = cb->args[0];
2660 	int idx = 0;
2661 
2662 	spin_lock_bh(&bat_priv->gw.list_lock);
2663 	cb->seq = bat_priv->gw.generation << 1 | 1;
2664 
2665 	hlist_for_each_entry(gw_node, &bat_priv->gw.gateway_list, list) {
2666 		if (idx++ < idx_skip)
2667 			continue;
2668 
2669 		if (batadv_iv_gw_dump_entry(msg, portid, cb, bat_priv,
2670 					    gw_node)) {
2671 			idx_skip = idx - 1;
2672 			goto unlock;
2673 		}
2674 	}
2675 
2676 	idx_skip = idx;
2677 unlock:
2678 	spin_unlock_bh(&bat_priv->gw.list_lock);
2679 
2680 	cb->args[0] = idx_skip;
2681 }
2682 
2683 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
2684 	.name = "BATMAN_IV",
2685 	.iface = {
2686 		.activate = batadv_iv_iface_activate,
2687 		.enable = batadv_iv_ogm_iface_enable,
2688 		.disable = batadv_iv_ogm_iface_disable,
2689 		.update_mac = batadv_iv_ogm_iface_update_mac,
2690 		.primary_set = batadv_iv_ogm_primary_iface_set,
2691 	},
2692 	.neigh = {
2693 		.cmp = batadv_iv_ogm_neigh_cmp,
2694 		.is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
2695 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2696 		.print = batadv_iv_neigh_print,
2697 #endif
2698 		.dump = batadv_iv_ogm_neigh_dump,
2699 	},
2700 	.orig = {
2701 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2702 		.print = batadv_iv_ogm_orig_print,
2703 #endif
2704 		.dump = batadv_iv_ogm_orig_dump,
2705 	},
2706 	.gw = {
2707 		.init_sel_class = batadv_iv_init_sel_class,
2708 		.get_best_gw_node = batadv_iv_gw_get_best_gw_node,
2709 		.is_eligible = batadv_iv_gw_is_eligible,
2710 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
2711 		.print = batadv_iv_gw_print,
2712 #endif
2713 		.dump = batadv_iv_gw_dump,
2714 	},
2715 };
2716 
2717 /**
2718  * batadv_iv_init() - B.A.T.M.A.N. IV initialization function
2719  *
2720  * Return: 0 on success or negative error number in case of failure
2721  */
2722 int __init batadv_iv_init(void)
2723 {
2724 	int ret;
2725 
2726 	/* batman originator packet */
2727 	ret = batadv_recv_handler_register(BATADV_IV_OGM,
2728 					   batadv_iv_ogm_receive);
2729 	if (ret < 0)
2730 		goto out;
2731 
2732 	ret = batadv_algo_register(&batadv_batman_iv);
2733 	if (ret < 0)
2734 		goto handler_unregister;
2735 
2736 	goto out;
2737 
2738 handler_unregister:
2739 	batadv_recv_handler_unregister(BATADV_IV_OGM);
2740 out:
2741 	return ret;
2742 }
2743