1 /* Copyright (C) 2007-2017  B.A.T.M.A.N. contributors:
2  *
3  * Marek Lindner, Simon Wunderlich
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of version 2 of the GNU General Public
7  * License as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include "soft-interface.h"
19 #include "main.h"
20 
21 #include <linux/atomic.h>
22 #include <linux/byteorder/generic.h>
23 #include <linux/cache.h>
24 #include <linux/compiler.h>
25 #include <linux/cpumask.h>
26 #include <linux/errno.h>
27 #include <linux/etherdevice.h>
28 #include <linux/ethtool.h>
29 #include <linux/fs.h>
30 #include <linux/if_ether.h>
31 #include <linux/if_vlan.h>
32 #include <linux/jiffies.h>
33 #include <linux/kernel.h>
34 #include <linux/kref.h>
35 #include <linux/list.h>
36 #include <linux/lockdep.h>
37 #include <linux/netdevice.h>
38 #include <linux/percpu.h>
39 #include <linux/printk.h>
40 #include <linux/random.h>
41 #include <linux/rculist.h>
42 #include <linux/rcupdate.h>
43 #include <linux/rtnetlink.h>
44 #include <linux/skbuff.h>
45 #include <linux/slab.h>
46 #include <linux/socket.h>
47 #include <linux/spinlock.h>
48 #include <linux/stddef.h>
49 #include <linux/string.h>
50 #include <linux/types.h>
51 
52 #include "bat_algo.h"
53 #include "bridge_loop_avoidance.h"
54 #include "debugfs.h"
55 #include "distributed-arp-table.h"
56 #include "gateway_client.h"
57 #include "gateway_common.h"
58 #include "hard-interface.h"
59 #include "multicast.h"
60 #include "network-coding.h"
61 #include "originator.h"
62 #include "packet.h"
63 #include "send.h"
64 #include "sysfs.h"
65 #include "translation-table.h"
66 
67 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);
68 static void batadv_get_drvinfo(struct net_device *dev,
69 			       struct ethtool_drvinfo *info);
70 static u32 batadv_get_msglevel(struct net_device *dev);
71 static void batadv_set_msglevel(struct net_device *dev, u32 value);
72 static u32 batadv_get_link(struct net_device *dev);
73 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data);
74 static void batadv_get_ethtool_stats(struct net_device *dev,
75 				     struct ethtool_stats *stats, u64 *data);
76 static int batadv_get_sset_count(struct net_device *dev, int stringset);
77 
78 static const struct ethtool_ops batadv_ethtool_ops = {
79 	.get_settings = batadv_get_settings,
80 	.get_drvinfo = batadv_get_drvinfo,
81 	.get_msglevel = batadv_get_msglevel,
82 	.set_msglevel = batadv_set_msglevel,
83 	.get_link = batadv_get_link,
84 	.get_strings = batadv_get_strings,
85 	.get_ethtool_stats = batadv_get_ethtool_stats,
86 	.get_sset_count = batadv_get_sset_count,
87 };
88 
89 int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
90 {
91 	int result;
92 
93 	/* TODO: We must check if we can release all references to non-payload
94 	 * data using skb_header_release in our skbs to allow skb_cow_header to
95 	 * work optimally. This means that those skbs are not allowed to read
96 	 * or write any data which is before the current position of skb->data
97 	 * after that call and thus allow other skbs with the same data buffer
98 	 * to write freely in that area.
99 	 */
100 	result = skb_cow_head(skb, len);
101 	if (result < 0)
102 		return result;
103 
104 	skb_push(skb, len);
105 	return 0;
106 }
107 
108 static int batadv_interface_open(struct net_device *dev)
109 {
110 	netif_start_queue(dev);
111 	return 0;
112 }
113 
114 static int batadv_interface_release(struct net_device *dev)
115 {
116 	netif_stop_queue(dev);
117 	return 0;
118 }
119 
120 /**
121  * batadv_sum_counter - Sum the cpu-local counters for index 'idx'
122  * @bat_priv: the bat priv with all the soft interface information
123  * @idx: index of counter to sum up
124  *
125  * Return: sum of all cpu-local counters
126  */
127 static u64 batadv_sum_counter(struct batadv_priv *bat_priv,  size_t idx)
128 {
129 	u64 *counters, sum = 0;
130 	int cpu;
131 
132 	for_each_possible_cpu(cpu) {
133 		counters = per_cpu_ptr(bat_priv->bat_counters, cpu);
134 		sum += counters[idx];
135 	}
136 
137 	return sum;
138 }
139 
140 static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
141 {
142 	struct batadv_priv *bat_priv = netdev_priv(dev);
143 	struct net_device_stats *stats = &bat_priv->stats;
144 
145 	stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
146 	stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
147 	stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
148 	stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
149 	stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
150 	return stats;
151 }
152 
153 static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
154 {
155 	struct batadv_priv *bat_priv = netdev_priv(dev);
156 	struct batadv_softif_vlan *vlan;
157 	struct sockaddr *addr = p;
158 	u8 old_addr[ETH_ALEN];
159 
160 	if (!is_valid_ether_addr(addr->sa_data))
161 		return -EADDRNOTAVAIL;
162 
163 	ether_addr_copy(old_addr, dev->dev_addr);
164 	ether_addr_copy(dev->dev_addr, addr->sa_data);
165 
166 	/* only modify transtable if it has been initialized before */
167 	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
168 		return 0;
169 
170 	rcu_read_lock();
171 	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
172 		batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
173 				       "mac address changed", false);
174 		batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
175 				    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
176 	}
177 	rcu_read_unlock();
178 
179 	return 0;
180 }
181 
182 static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
183 {
184 	/* check ranges */
185 	if ((new_mtu < 68) || (new_mtu > batadv_hardif_min_mtu(dev)))
186 		return -EINVAL;
187 
188 	dev->mtu = new_mtu;
189 
190 	return 0;
191 }
192 
193 /**
194  * batadv_interface_set_rx_mode - set the rx mode of a device
195  * @dev: registered network device to modify
196  *
197  * We do not actually need to set any rx filters for the virtual batman
198  * soft interface. However a dummy handler enables a user to set static
199  * multicast listeners for instance.
200  */
201 static void batadv_interface_set_rx_mode(struct net_device *dev)
202 {
203 }
204 
205 static int batadv_interface_tx(struct sk_buff *skb,
206 			       struct net_device *soft_iface)
207 {
208 	struct ethhdr *ethhdr;
209 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
210 	struct batadv_hard_iface *primary_if = NULL;
211 	struct batadv_bcast_packet *bcast_packet;
212 	static const u8 stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00,
213 					      0x00, 0x00};
214 	static const u8 ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00,
215 					       0x00, 0x00};
216 	enum batadv_dhcp_recipient dhcp_rcp = BATADV_DHCP_NO;
217 	u8 *dst_hint = NULL, chaddr[ETH_ALEN];
218 	struct vlan_ethhdr *vhdr;
219 	unsigned int header_len = 0;
220 	int data_len = skb->len, ret;
221 	unsigned long brd_delay = 1;
222 	bool do_bcast = false, client_added;
223 	unsigned short vid;
224 	u32 seqno;
225 	int gw_mode;
226 	enum batadv_forw_mode forw_mode;
227 	struct batadv_orig_node *mcast_single_orig = NULL;
228 	int network_offset = ETH_HLEN;
229 
230 	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
231 		goto dropped;
232 
233 	netif_trans_update(soft_iface);
234 	vid = batadv_get_vid(skb, 0);
235 	ethhdr = eth_hdr(skb);
236 
237 	switch (ntohs(ethhdr->h_proto)) {
238 	case ETH_P_8021Q:
239 		vhdr = vlan_eth_hdr(skb);
240 
241 		/* drop batman-in-batman packets to prevent loops */
242 		if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN)) {
243 			network_offset += VLAN_HLEN;
244 			break;
245 		}
246 
247 		/* fall through */
248 	case ETH_P_BATMAN:
249 		goto dropped;
250 	}
251 
252 	skb_set_network_header(skb, network_offset);
253 
254 	if (batadv_bla_tx(bat_priv, skb, vid))
255 		goto dropped;
256 
257 	/* skb->data might have been reallocated by batadv_bla_tx() */
258 	ethhdr = eth_hdr(skb);
259 
260 	/* Register the client MAC in the transtable */
261 	if (!is_multicast_ether_addr(ethhdr->h_source) &&
262 	    !batadv_bla_is_loopdetect_mac(ethhdr->h_source)) {
263 		client_added = batadv_tt_local_add(soft_iface, ethhdr->h_source,
264 						   vid, skb->skb_iif,
265 						   skb->mark);
266 		if (!client_added)
267 			goto dropped;
268 	}
269 
270 	/* don't accept stp packets. STP does not help in meshes.
271 	 * better use the bridge loop avoidance ...
272 	 *
273 	 * The same goes for ECTP sent at least by some Cisco Switches,
274 	 * it might confuse the mesh when used with bridge loop avoidance.
275 	 */
276 	if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
277 		goto dropped;
278 
279 	if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
280 		goto dropped;
281 
282 	gw_mode = atomic_read(&bat_priv->gw.mode);
283 	if (is_multicast_ether_addr(ethhdr->h_dest)) {
284 		/* if gw mode is off, broadcast every packet */
285 		if (gw_mode == BATADV_GW_MODE_OFF) {
286 			do_bcast = true;
287 			goto send;
288 		}
289 
290 		dhcp_rcp = batadv_gw_dhcp_recipient_get(skb, &header_len,
291 							chaddr);
292 		/* skb->data may have been modified by
293 		 * batadv_gw_dhcp_recipient_get()
294 		 */
295 		ethhdr = eth_hdr(skb);
296 		/* if gw_mode is on, broadcast any non-DHCP message.
297 		 * All the DHCP packets are going to be sent as unicast
298 		 */
299 		if (dhcp_rcp == BATADV_DHCP_NO) {
300 			do_bcast = true;
301 			goto send;
302 		}
303 
304 		if (dhcp_rcp == BATADV_DHCP_TO_CLIENT)
305 			dst_hint = chaddr;
306 		else if ((gw_mode == BATADV_GW_MODE_SERVER) &&
307 			 (dhcp_rcp == BATADV_DHCP_TO_SERVER))
308 			/* gateways should not forward any DHCP message if
309 			 * directed to a DHCP server
310 			 */
311 			goto dropped;
312 
313 send:
314 		if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) {
315 			forw_mode = batadv_mcast_forw_mode(bat_priv, skb,
316 							   &mcast_single_orig);
317 			if (forw_mode == BATADV_FORW_NONE)
318 				goto dropped;
319 
320 			if (forw_mode == BATADV_FORW_SINGLE)
321 				do_bcast = false;
322 		}
323 	}
324 
325 	batadv_skb_set_priority(skb, 0);
326 
327 	/* ethernet packet should be broadcasted */
328 	if (do_bcast) {
329 		primary_if = batadv_primary_if_get_selected(bat_priv);
330 		if (!primary_if)
331 			goto dropped;
332 
333 		/* in case of ARP request, we do not immediately broadcasti the
334 		 * packet, instead we first wait for DAT to try to retrieve the
335 		 * correct ARP entry
336 		 */
337 		if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
338 			brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
339 
340 		if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
341 			goto dropped;
342 
343 		bcast_packet = (struct batadv_bcast_packet *)skb->data;
344 		bcast_packet->version = BATADV_COMPAT_VERSION;
345 		bcast_packet->ttl = BATADV_TTL;
346 
347 		/* batman packet type: broadcast */
348 		bcast_packet->packet_type = BATADV_BCAST;
349 		bcast_packet->reserved = 0;
350 
351 		/* hw address of first interface is the orig mac because only
352 		 * this mac is known throughout the mesh
353 		 */
354 		ether_addr_copy(bcast_packet->orig,
355 				primary_if->net_dev->dev_addr);
356 
357 		/* set broadcast sequence number */
358 		seqno = atomic_inc_return(&bat_priv->bcast_seqno);
359 		bcast_packet->seqno = htonl(seqno);
360 
361 		batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay, true);
362 
363 		/* a copy is stored in the bcast list, therefore removing
364 		 * the original skb.
365 		 */
366 		consume_skb(skb);
367 
368 	/* unicast packet */
369 	} else {
370 		/* DHCP packets going to a server will use the GW feature */
371 		if (dhcp_rcp == BATADV_DHCP_TO_SERVER) {
372 			ret = batadv_gw_out_of_range(bat_priv, skb);
373 			if (ret)
374 				goto dropped;
375 			ret = batadv_send_skb_via_gw(bat_priv, skb, vid);
376 		} else if (mcast_single_orig) {
377 			ret = batadv_send_skb_unicast(bat_priv, skb,
378 						      BATADV_UNICAST, 0,
379 						      mcast_single_orig, vid);
380 		} else {
381 			if (batadv_dat_snoop_outgoing_arp_request(bat_priv,
382 								  skb))
383 				goto dropped;
384 
385 			batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
386 
387 			ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
388 						     vid);
389 		}
390 		if (ret != NET_XMIT_SUCCESS)
391 			goto dropped_freed;
392 	}
393 
394 	batadv_inc_counter(bat_priv, BATADV_CNT_TX);
395 	batadv_add_counter(bat_priv, BATADV_CNT_TX_BYTES, data_len);
396 	goto end;
397 
398 dropped:
399 	kfree_skb(skb);
400 dropped_freed:
401 	batadv_inc_counter(bat_priv, BATADV_CNT_TX_DROPPED);
402 end:
403 	if (mcast_single_orig)
404 		batadv_orig_node_put(mcast_single_orig);
405 	if (primary_if)
406 		batadv_hardif_put(primary_if);
407 	return NETDEV_TX_OK;
408 }
409 
410 /**
411  * batadv_interface_rx - receive ethernet frame on local batman-adv interface
412  * @soft_iface: local interface which will receive the ethernet frame
413  * @skb: ethernet frame for @soft_iface
414  * @hdr_size: size of already parsed batman-adv header
415  * @orig_node: originator from which the batman-adv packet was sent
416  *
417  * Sends a ethernet frame to the receive path of the local @soft_iface.
418  * skb->data has still point to the batman-adv header with the size @hdr_size.
419  * The caller has to have parsed this header already and made sure that at least
420  * @hdr_size bytes are still available for pull in @skb.
421  *
422  * The packet may still get dropped. This can happen when the encapsulated
423  * ethernet frame is invalid or contains again an batman-adv packet. Also
424  * unicast packets will be dropped directly when it was sent between two
425  * isolated clients.
426  */
427 void batadv_interface_rx(struct net_device *soft_iface,
428 			 struct sk_buff *skb, int hdr_size,
429 			 struct batadv_orig_node *orig_node)
430 {
431 	struct batadv_bcast_packet *batadv_bcast_packet;
432 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
433 	struct vlan_ethhdr *vhdr;
434 	struct ethhdr *ethhdr;
435 	unsigned short vid;
436 	bool is_bcast;
437 
438 	batadv_bcast_packet = (struct batadv_bcast_packet *)skb->data;
439 	is_bcast = (batadv_bcast_packet->packet_type == BATADV_BCAST);
440 
441 	skb_pull_rcsum(skb, hdr_size);
442 	skb_reset_mac_header(skb);
443 
444 	/* clean the netfilter state now that the batman-adv header has been
445 	 * removed
446 	 */
447 	nf_reset(skb);
448 
449 	if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
450 		goto dropped;
451 
452 	vid = batadv_get_vid(skb, 0);
453 	ethhdr = eth_hdr(skb);
454 
455 	switch (ntohs(ethhdr->h_proto)) {
456 	case ETH_P_8021Q:
457 		if (!pskb_may_pull(skb, VLAN_ETH_HLEN))
458 			goto dropped;
459 
460 		vhdr = (struct vlan_ethhdr *)skb->data;
461 
462 		/* drop batman-in-batman packets to prevent loops */
463 		if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN))
464 			break;
465 
466 		/* fall through */
467 	case ETH_P_BATMAN:
468 		goto dropped;
469 	}
470 
471 	/* skb->dev & skb->pkt_type are set here */
472 	skb->protocol = eth_type_trans(skb, soft_iface);
473 
474 	/* should not be necessary anymore as we use skb_pull_rcsum()
475 	 * TODO: please verify this and remove this TODO
476 	 * -- Dec 21st 2009, Simon Wunderlich
477 	 */
478 
479 	/* skb->ip_summed = CHECKSUM_UNNECESSARY; */
480 
481 	batadv_inc_counter(bat_priv, BATADV_CNT_RX);
482 	batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
483 			   skb->len + ETH_HLEN);
484 
485 	/* Let the bridge loop avoidance check the packet. If will
486 	 * not handle it, we can safely push it up.
487 	 */
488 	if (batadv_bla_rx(bat_priv, skb, vid, is_bcast))
489 		goto out;
490 
491 	if (orig_node)
492 		batadv_tt_add_temporary_global_entry(bat_priv, orig_node,
493 						     ethhdr->h_source, vid);
494 
495 	if (is_multicast_ether_addr(ethhdr->h_dest)) {
496 		/* set the mark on broadcast packets if AP isolation is ON and
497 		 * the packet is coming from an "isolated" client
498 		 */
499 		if (batadv_vlan_ap_isola_get(bat_priv, vid) &&
500 		    batadv_tt_global_is_isolated(bat_priv, ethhdr->h_source,
501 						 vid)) {
502 			/* save bits in skb->mark not covered by the mask and
503 			 * apply the mark on the rest
504 			 */
505 			skb->mark &= ~bat_priv->isolation_mark_mask;
506 			skb->mark |= bat_priv->isolation_mark;
507 		}
508 	} else if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source,
509 					 ethhdr->h_dest, vid)) {
510 		goto dropped;
511 	}
512 
513 	netif_rx(skb);
514 	goto out;
515 
516 dropped:
517 	kfree_skb(skb);
518 out:
519 	return;
520 }
521 
522 /**
523  * batadv_softif_vlan_release - release vlan from lists and queue for free after
524  *  rcu grace period
525  * @ref: kref pointer of the vlan object
526  */
527 static void batadv_softif_vlan_release(struct kref *ref)
528 {
529 	struct batadv_softif_vlan *vlan;
530 
531 	vlan = container_of(ref, struct batadv_softif_vlan, refcount);
532 
533 	spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock);
534 	hlist_del_rcu(&vlan->list);
535 	spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock);
536 
537 	kfree_rcu(vlan, rcu);
538 }
539 
540 /**
541  * batadv_softif_vlan_put - decrease the vlan object refcounter and
542  *  possibly release it
543  * @vlan: the vlan object to release
544  */
545 void batadv_softif_vlan_put(struct batadv_softif_vlan *vlan)
546 {
547 	if (!vlan)
548 		return;
549 
550 	kref_put(&vlan->refcount, batadv_softif_vlan_release);
551 }
552 
553 /**
554  * batadv_softif_vlan_get - get the vlan object for a specific vid
555  * @bat_priv: the bat priv with all the soft interface information
556  * @vid: the identifier of the vlan object to retrieve
557  *
558  * Return: the private data of the vlan matching the vid passed as argument or
559  * NULL otherwise. The refcounter of the returned object is incremented by 1.
560  */
561 struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv,
562 						  unsigned short vid)
563 {
564 	struct batadv_softif_vlan *vlan_tmp, *vlan = NULL;
565 
566 	rcu_read_lock();
567 	hlist_for_each_entry_rcu(vlan_tmp, &bat_priv->softif_vlan_list, list) {
568 		if (vlan_tmp->vid != vid)
569 			continue;
570 
571 		if (!kref_get_unless_zero(&vlan_tmp->refcount))
572 			continue;
573 
574 		vlan = vlan_tmp;
575 		break;
576 	}
577 	rcu_read_unlock();
578 
579 	return vlan;
580 }
581 
582 /**
583  * batadv_softif_create_vlan - allocate the needed resources for a new vlan
584  * @bat_priv: the bat priv with all the soft interface information
585  * @vid: the VLAN identifier
586  *
587  * Return: 0 on success, a negative error otherwise.
588  */
589 int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
590 {
591 	struct batadv_softif_vlan *vlan;
592 	int err;
593 
594 	vlan = batadv_softif_vlan_get(bat_priv, vid);
595 	if (vlan) {
596 		batadv_softif_vlan_put(vlan);
597 		return -EEXIST;
598 	}
599 
600 	vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
601 	if (!vlan)
602 		return -ENOMEM;
603 
604 	vlan->bat_priv = bat_priv;
605 	vlan->vid = vid;
606 	kref_init(&vlan->refcount);
607 
608 	atomic_set(&vlan->ap_isolation, 0);
609 
610 	err = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
611 	if (err) {
612 		kfree(vlan);
613 		return err;
614 	}
615 
616 	spin_lock_bh(&bat_priv->softif_vlan_list_lock);
617 	kref_get(&vlan->refcount);
618 	hlist_add_head_rcu(&vlan->list, &bat_priv->softif_vlan_list);
619 	spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
620 
621 	/* add a new TT local entry. This one will be marked with the NOPURGE
622 	 * flag
623 	 */
624 	batadv_tt_local_add(bat_priv->soft_iface,
625 			    bat_priv->soft_iface->dev_addr, vid,
626 			    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
627 
628 	/* don't return reference to new softif_vlan */
629 	batadv_softif_vlan_put(vlan);
630 
631 	return 0;
632 }
633 
634 /**
635  * batadv_softif_destroy_vlan - remove and destroy a softif_vlan object
636  * @bat_priv: the bat priv with all the soft interface information
637  * @vlan: the object to remove
638  */
639 static void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
640 				       struct batadv_softif_vlan *vlan)
641 {
642 	/* explicitly remove the associated TT local entry because it is marked
643 	 * with the NOPURGE flag
644 	 */
645 	batadv_tt_local_remove(bat_priv, bat_priv->soft_iface->dev_addr,
646 			       vlan->vid, "vlan interface destroyed", false);
647 
648 	batadv_sysfs_del_vlan(bat_priv, vlan);
649 	batadv_softif_vlan_put(vlan);
650 }
651 
652 /**
653  * batadv_interface_add_vid - ndo_add_vid API implementation
654  * @dev: the netdev of the mesh interface
655  * @proto: protocol of the the vlan id
656  * @vid: identifier of the new vlan
657  *
658  * Set up all the internal structures for handling the new vlan on top of the
659  * mesh interface
660  *
661  * Return: 0 on success or a negative error code in case of failure.
662  */
663 static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
664 				    unsigned short vid)
665 {
666 	struct batadv_priv *bat_priv = netdev_priv(dev);
667 	struct batadv_softif_vlan *vlan;
668 	int ret;
669 
670 	/* only 802.1Q vlans are supported.
671 	 * batman-adv does not know how to handle other types
672 	 */
673 	if (proto != htons(ETH_P_8021Q))
674 		return -EINVAL;
675 
676 	vid |= BATADV_VLAN_HAS_TAG;
677 
678 	/* if a new vlan is getting created and it already exists, it means that
679 	 * it was not deleted yet. batadv_softif_vlan_get() increases the
680 	 * refcount in order to revive the object.
681 	 *
682 	 * if it does not exist then create it.
683 	 */
684 	vlan = batadv_softif_vlan_get(bat_priv, vid);
685 	if (!vlan)
686 		return batadv_softif_create_vlan(bat_priv, vid);
687 
688 	/* recreate the sysfs object if it was already destroyed (and it should
689 	 * be since we received a kill_vid() for this vlan
690 	 */
691 	if (!vlan->kobj) {
692 		ret = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
693 		if (ret) {
694 			batadv_softif_vlan_put(vlan);
695 			return ret;
696 		}
697 	}
698 
699 	/* add a new TT local entry. This one will be marked with the NOPURGE
700 	 * flag. This must be added again, even if the vlan object already
701 	 * exists, because the entry was deleted by kill_vid()
702 	 */
703 	batadv_tt_local_add(bat_priv->soft_iface,
704 			    bat_priv->soft_iface->dev_addr, vid,
705 			    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
706 
707 	return 0;
708 }
709 
710 /**
711  * batadv_interface_kill_vid - ndo_kill_vid API implementation
712  * @dev: the netdev of the mesh interface
713  * @proto: protocol of the the vlan id
714  * @vid: identifier of the deleted vlan
715  *
716  * Destroy all the internal structures used to handle the vlan identified by vid
717  * on top of the mesh interface
718  *
719  * Return: 0 on success, -EINVAL if the specified prototype is not ETH_P_8021Q
720  * or -ENOENT if the specified vlan id wasn't registered.
721  */
722 static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
723 				     unsigned short vid)
724 {
725 	struct batadv_priv *bat_priv = netdev_priv(dev);
726 	struct batadv_softif_vlan *vlan;
727 
728 	/* only 802.1Q vlans are supported. batman-adv does not know how to
729 	 * handle other types
730 	 */
731 	if (proto != htons(ETH_P_8021Q))
732 		return -EINVAL;
733 
734 	vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
735 	if (!vlan)
736 		return -ENOENT;
737 
738 	batadv_softif_destroy_vlan(bat_priv, vlan);
739 
740 	/* finally free the vlan object */
741 	batadv_softif_vlan_put(vlan);
742 
743 	return 0;
744 }
745 
746 /* batman-adv network devices have devices nesting below it and are a special
747  * "super class" of normal network devices; split their locks off into a
748  * separate class since they always nest.
749  */
750 static struct lock_class_key batadv_netdev_xmit_lock_key;
751 static struct lock_class_key batadv_netdev_addr_lock_key;
752 
753 /**
754  * batadv_set_lockdep_class_one - Set lockdep class for a single tx queue
755  * @dev: device which owns the tx queue
756  * @txq: tx queue to modify
757  * @_unused: always NULL
758  */
759 static void batadv_set_lockdep_class_one(struct net_device *dev,
760 					 struct netdev_queue *txq,
761 					 void *_unused)
762 {
763 	lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
764 }
765 
766 /**
767  * batadv_set_lockdep_class - Set txq and addr_list lockdep class
768  * @dev: network device to modify
769  */
770 static void batadv_set_lockdep_class(struct net_device *dev)
771 {
772 	lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
773 	netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
774 }
775 
776 /**
777  * batadv_softif_init_late - late stage initialization of soft interface
778  * @dev: registered network device to modify
779  *
780  * Return: error code on failures
781  */
782 static int batadv_softif_init_late(struct net_device *dev)
783 {
784 	struct batadv_priv *bat_priv;
785 	u32 random_seqno;
786 	int ret;
787 	size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
788 
789 	batadv_set_lockdep_class(dev);
790 
791 	bat_priv = netdev_priv(dev);
792 	bat_priv->soft_iface = dev;
793 
794 	/* batadv_interface_stats() needs to be available as soon as
795 	 * register_netdevice() has been called
796 	 */
797 	bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(u64));
798 	if (!bat_priv->bat_counters)
799 		return -ENOMEM;
800 
801 	atomic_set(&bat_priv->aggregated_ogms, 1);
802 	atomic_set(&bat_priv->bonding, 0);
803 #ifdef CONFIG_BATMAN_ADV_BLA
804 	atomic_set(&bat_priv->bridge_loop_avoidance, 1);
805 #endif
806 #ifdef CONFIG_BATMAN_ADV_DAT
807 	atomic_set(&bat_priv->distributed_arp_table, 1);
808 #endif
809 #ifdef CONFIG_BATMAN_ADV_MCAST
810 	bat_priv->mcast.querier_ipv4.exists = false;
811 	bat_priv->mcast.querier_ipv4.shadowing = false;
812 	bat_priv->mcast.querier_ipv6.exists = false;
813 	bat_priv->mcast.querier_ipv6.shadowing = false;
814 	bat_priv->mcast.flags = BATADV_NO_FLAGS;
815 	atomic_set(&bat_priv->multicast_mode, 1);
816 	atomic_set(&bat_priv->mcast.num_disabled, 0);
817 	atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
818 	atomic_set(&bat_priv->mcast.num_want_all_ipv4, 0);
819 	atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
820 #endif
821 	atomic_set(&bat_priv->gw.mode, BATADV_GW_MODE_OFF);
822 	atomic_set(&bat_priv->gw.sel_class, 20);
823 	atomic_set(&bat_priv->gw.bandwidth_down, 100);
824 	atomic_set(&bat_priv->gw.bandwidth_up, 20);
825 	atomic_set(&bat_priv->orig_interval, 1000);
826 	atomic_set(&bat_priv->hop_penalty, 30);
827 #ifdef CONFIG_BATMAN_ADV_DEBUG
828 	atomic_set(&bat_priv->log_level, 0);
829 #endif
830 	atomic_set(&bat_priv->fragmentation, 1);
831 	atomic_set(&bat_priv->packet_size_max, ETH_DATA_LEN);
832 	atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
833 	atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
834 
835 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
836 	atomic_set(&bat_priv->bcast_seqno, 1);
837 	atomic_set(&bat_priv->tt.vn, 0);
838 	atomic_set(&bat_priv->tt.local_changes, 0);
839 	atomic_set(&bat_priv->tt.ogm_append_cnt, 0);
840 #ifdef CONFIG_BATMAN_ADV_BLA
841 	atomic_set(&bat_priv->bla.num_requests, 0);
842 #endif
843 	atomic_set(&bat_priv->tp_num, 0);
844 
845 	bat_priv->tt.last_changeset = NULL;
846 	bat_priv->tt.last_changeset_len = 0;
847 	bat_priv->isolation_mark = 0;
848 	bat_priv->isolation_mark_mask = 0;
849 
850 	/* randomize initial seqno to avoid collision */
851 	get_random_bytes(&random_seqno, sizeof(random_seqno));
852 	atomic_set(&bat_priv->frag_seqno, random_seqno);
853 
854 	bat_priv->primary_if = NULL;
855 	bat_priv->num_ifaces = 0;
856 
857 	batadv_nc_init_bat_priv(bat_priv);
858 
859 	ret = batadv_algo_select(bat_priv, batadv_routing_algo);
860 	if (ret < 0)
861 		goto free_bat_counters;
862 
863 	ret = batadv_debugfs_add_meshif(dev);
864 	if (ret < 0)
865 		goto free_bat_counters;
866 
867 	ret = batadv_mesh_init(dev);
868 	if (ret < 0)
869 		goto unreg_debugfs;
870 
871 	return 0;
872 
873 unreg_debugfs:
874 	batadv_debugfs_del_meshif(dev);
875 free_bat_counters:
876 	free_percpu(bat_priv->bat_counters);
877 	bat_priv->bat_counters = NULL;
878 
879 	return ret;
880 }
881 
882 /**
883  * batadv_softif_slave_add - Add a slave interface to a batadv_soft_interface
884  * @dev: batadv_soft_interface used as master interface
885  * @slave_dev: net_device which should become the slave interface
886  *
887  * Return: 0 if successful or error otherwise.
888  */
889 static int batadv_softif_slave_add(struct net_device *dev,
890 				   struct net_device *slave_dev)
891 {
892 	struct batadv_hard_iface *hard_iface;
893 	struct net *net = dev_net(dev);
894 	int ret = -EINVAL;
895 
896 	hard_iface = batadv_hardif_get_by_netdev(slave_dev);
897 	if (!hard_iface || hard_iface->soft_iface)
898 		goto out;
899 
900 	ret = batadv_hardif_enable_interface(hard_iface, net, dev->name);
901 
902 out:
903 	if (hard_iface)
904 		batadv_hardif_put(hard_iface);
905 	return ret;
906 }
907 
908 /**
909  * batadv_softif_slave_del - Delete a slave iface from a batadv_soft_interface
910  * @dev: batadv_soft_interface used as master interface
911  * @slave_dev: net_device which should be removed from the master interface
912  *
913  * Return: 0 if successful or error otherwise.
914  */
915 static int batadv_softif_slave_del(struct net_device *dev,
916 				   struct net_device *slave_dev)
917 {
918 	struct batadv_hard_iface *hard_iface;
919 	int ret = -EINVAL;
920 
921 	hard_iface = batadv_hardif_get_by_netdev(slave_dev);
922 
923 	if (!hard_iface || hard_iface->soft_iface != dev)
924 		goto out;
925 
926 	batadv_hardif_disable_interface(hard_iface, BATADV_IF_CLEANUP_KEEP);
927 	ret = 0;
928 
929 out:
930 	if (hard_iface)
931 		batadv_hardif_put(hard_iface);
932 	return ret;
933 }
934 
935 static const struct net_device_ops batadv_netdev_ops = {
936 	.ndo_init = batadv_softif_init_late,
937 	.ndo_open = batadv_interface_open,
938 	.ndo_stop = batadv_interface_release,
939 	.ndo_get_stats = batadv_interface_stats,
940 	.ndo_vlan_rx_add_vid = batadv_interface_add_vid,
941 	.ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
942 	.ndo_set_mac_address = batadv_interface_set_mac_addr,
943 	.ndo_change_mtu = batadv_interface_change_mtu,
944 	.ndo_set_rx_mode = batadv_interface_set_rx_mode,
945 	.ndo_start_xmit = batadv_interface_tx,
946 	.ndo_validate_addr = eth_validate_addr,
947 	.ndo_add_slave = batadv_softif_slave_add,
948 	.ndo_del_slave = batadv_softif_slave_del,
949 };
950 
951 /**
952  * batadv_softif_free - Deconstructor of batadv_soft_interface
953  * @dev: Device to cleanup and remove
954  */
955 static void batadv_softif_free(struct net_device *dev)
956 {
957 	batadv_debugfs_del_meshif(dev);
958 	batadv_mesh_free(dev);
959 
960 	/* some scheduled RCU callbacks need the bat_priv struct to accomplish
961 	 * their tasks. Wait for them all to be finished before freeing the
962 	 * netdev and its private data (bat_priv)
963 	 */
964 	rcu_barrier();
965 
966 	free_netdev(dev);
967 }
968 
969 /**
970  * batadv_softif_init_early - early stage initialization of soft interface
971  * @dev: registered network device to modify
972  */
973 static void batadv_softif_init_early(struct net_device *dev)
974 {
975 	struct batadv_priv *priv = netdev_priv(dev);
976 
977 	ether_setup(dev);
978 
979 	dev->netdev_ops = &batadv_netdev_ops;
980 	dev->destructor = batadv_softif_free;
981 	dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_NETNS_LOCAL;
982 	dev->priv_flags |= IFF_NO_QUEUE;
983 
984 	/* can't call min_mtu, because the needed variables
985 	 * have not been initialized yet
986 	 */
987 	dev->mtu = ETH_DATA_LEN;
988 
989 	/* generate random address */
990 	eth_hw_addr_random(dev);
991 
992 	dev->ethtool_ops = &batadv_ethtool_ops;
993 
994 	memset(priv, 0, sizeof(*priv));
995 }
996 
997 struct net_device *batadv_softif_create(struct net *net, const char *name)
998 {
999 	struct net_device *soft_iface;
1000 	int ret;
1001 
1002 	soft_iface = alloc_netdev(sizeof(struct batadv_priv), name,
1003 				  NET_NAME_UNKNOWN, batadv_softif_init_early);
1004 	if (!soft_iface)
1005 		return NULL;
1006 
1007 	dev_net_set(soft_iface, net);
1008 
1009 	soft_iface->rtnl_link_ops = &batadv_link_ops;
1010 
1011 	ret = register_netdevice(soft_iface);
1012 	if (ret < 0) {
1013 		pr_err("Unable to register the batman interface '%s': %i\n",
1014 		       name, ret);
1015 		free_netdev(soft_iface);
1016 		return NULL;
1017 	}
1018 
1019 	return soft_iface;
1020 }
1021 
1022 /**
1023  * batadv_softif_destroy_sysfs - deletion of batadv_soft_interface via sysfs
1024  * @soft_iface: the to-be-removed batman-adv interface
1025  */
1026 void batadv_softif_destroy_sysfs(struct net_device *soft_iface)
1027 {
1028 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
1029 	struct batadv_softif_vlan *vlan;
1030 
1031 	ASSERT_RTNL();
1032 
1033 	/* destroy the "untagged" VLAN */
1034 	vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
1035 	if (vlan) {
1036 		batadv_softif_destroy_vlan(bat_priv, vlan);
1037 		batadv_softif_vlan_put(vlan);
1038 	}
1039 
1040 	batadv_sysfs_del_meshif(soft_iface);
1041 	unregister_netdevice(soft_iface);
1042 }
1043 
1044 /**
1045  * batadv_softif_destroy_netlink - deletion of batadv_soft_interface via netlink
1046  * @soft_iface: the to-be-removed batman-adv interface
1047  * @head: list pointer
1048  */
1049 static void batadv_softif_destroy_netlink(struct net_device *soft_iface,
1050 					  struct list_head *head)
1051 {
1052 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
1053 	struct batadv_hard_iface *hard_iface;
1054 	struct batadv_softif_vlan *vlan;
1055 
1056 	list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
1057 		if (hard_iface->soft_iface == soft_iface)
1058 			batadv_hardif_disable_interface(hard_iface,
1059 							BATADV_IF_CLEANUP_KEEP);
1060 	}
1061 
1062 	/* destroy the "untagged" VLAN */
1063 	vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
1064 	if (vlan) {
1065 		batadv_softif_destroy_vlan(bat_priv, vlan);
1066 		batadv_softif_vlan_put(vlan);
1067 	}
1068 
1069 	batadv_sysfs_del_meshif(soft_iface);
1070 	unregister_netdevice_queue(soft_iface, head);
1071 }
1072 
1073 bool batadv_softif_is_valid(const struct net_device *net_dev)
1074 {
1075 	if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
1076 		return true;
1077 
1078 	return false;
1079 }
1080 
1081 struct rtnl_link_ops batadv_link_ops __read_mostly = {
1082 	.kind		= "batadv",
1083 	.priv_size	= sizeof(struct batadv_priv),
1084 	.setup		= batadv_softif_init_early,
1085 	.dellink	= batadv_softif_destroy_netlink,
1086 };
1087 
1088 /* ethtool */
1089 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1090 {
1091 	cmd->supported = 0;
1092 	cmd->advertising = 0;
1093 	ethtool_cmd_speed_set(cmd, SPEED_10);
1094 	cmd->duplex = DUPLEX_FULL;
1095 	cmd->port = PORT_TP;
1096 	cmd->phy_address = 0;
1097 	cmd->transceiver = XCVR_INTERNAL;
1098 	cmd->autoneg = AUTONEG_DISABLE;
1099 	cmd->maxtxpkt = 0;
1100 	cmd->maxrxpkt = 0;
1101 
1102 	return 0;
1103 }
1104 
1105 static void batadv_get_drvinfo(struct net_device *dev,
1106 			       struct ethtool_drvinfo *info)
1107 {
1108 	strlcpy(info->driver, "B.A.T.M.A.N. advanced", sizeof(info->driver));
1109 	strlcpy(info->version, BATADV_SOURCE_VERSION, sizeof(info->version));
1110 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1111 	strlcpy(info->bus_info, "batman", sizeof(info->bus_info));
1112 }
1113 
1114 static u32 batadv_get_msglevel(struct net_device *dev)
1115 {
1116 	return -EOPNOTSUPP;
1117 }
1118 
1119 static void batadv_set_msglevel(struct net_device *dev, u32 value)
1120 {
1121 }
1122 
1123 static u32 batadv_get_link(struct net_device *dev)
1124 {
1125 	return 1;
1126 }
1127 
1128 /* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
1129  * Declare each description string in struct.name[] to get fixed sized buffer
1130  * and compile time checking for strings longer than ETH_GSTRING_LEN.
1131  */
1132 static const struct {
1133 	const char name[ETH_GSTRING_LEN];
1134 } batadv_counters_strings[] = {
1135 	{ "tx" },
1136 	{ "tx_bytes" },
1137 	{ "tx_dropped" },
1138 	{ "rx" },
1139 	{ "rx_bytes" },
1140 	{ "forward" },
1141 	{ "forward_bytes" },
1142 	{ "mgmt_tx" },
1143 	{ "mgmt_tx_bytes" },
1144 	{ "mgmt_rx" },
1145 	{ "mgmt_rx_bytes" },
1146 	{ "frag_tx" },
1147 	{ "frag_tx_bytes" },
1148 	{ "frag_rx" },
1149 	{ "frag_rx_bytes" },
1150 	{ "frag_fwd" },
1151 	{ "frag_fwd_bytes" },
1152 	{ "tt_request_tx" },
1153 	{ "tt_request_rx" },
1154 	{ "tt_response_tx" },
1155 	{ "tt_response_rx" },
1156 	{ "tt_roam_adv_tx" },
1157 	{ "tt_roam_adv_rx" },
1158 #ifdef CONFIG_BATMAN_ADV_DAT
1159 	{ "dat_get_tx" },
1160 	{ "dat_get_rx" },
1161 	{ "dat_put_tx" },
1162 	{ "dat_put_rx" },
1163 	{ "dat_cached_reply_tx" },
1164 #endif
1165 #ifdef CONFIG_BATMAN_ADV_NC
1166 	{ "nc_code" },
1167 	{ "nc_code_bytes" },
1168 	{ "nc_recode" },
1169 	{ "nc_recode_bytes" },
1170 	{ "nc_buffer" },
1171 	{ "nc_decode" },
1172 	{ "nc_decode_bytes" },
1173 	{ "nc_decode_failed" },
1174 	{ "nc_sniffed" },
1175 #endif
1176 };
1177 
1178 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1179 {
1180 	if (stringset == ETH_SS_STATS)
1181 		memcpy(data, batadv_counters_strings,
1182 		       sizeof(batadv_counters_strings));
1183 }
1184 
1185 static void batadv_get_ethtool_stats(struct net_device *dev,
1186 				     struct ethtool_stats *stats, u64 *data)
1187 {
1188 	struct batadv_priv *bat_priv = netdev_priv(dev);
1189 	int i;
1190 
1191 	for (i = 0; i < BATADV_CNT_NUM; i++)
1192 		data[i] = batadv_sum_counter(bat_priv, i);
1193 }
1194 
1195 static int batadv_get_sset_count(struct net_device *dev, int stringset)
1196 {
1197 	if (stringset == ETH_SS_STATS)
1198 		return BATADV_CNT_NUM;
1199 
1200 	return -EOPNOTSUPP;
1201 }
1202