1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (C) 2007-2020  B.A.T.M.A.N. contributors:
3 *
4 * Marek Lindner, Simon Wunderlich
5 */
6
7#include "soft-interface.h"
8#include "main.h"
9
10#include <linux/atomic.h>
11#include <linux/byteorder/generic.h>
12#include <linux/cache.h>
13#include <linux/compiler.h>
14#include <linux/cpumask.h>
15#include <linux/errno.h>
16#include <linux/etherdevice.h>
17#include <linux/ethtool.h>
18#include <linux/gfp.h>
19#include <linux/if_ether.h>
20#include <linux/if_vlan.h>
21#include <linux/jiffies.h>
22#include <linux/kernel.h>
23#include <linux/kref.h>
24#include <linux/list.h>
25#include <linux/lockdep.h>
26#include <linux/netdevice.h>
27#include <linux/netlink.h>
28#include <linux/percpu.h>
29#include <linux/printk.h>
30#include <linux/random.h>
31#include <linux/rculist.h>
32#include <linux/rcupdate.h>
33#include <linux/rtnetlink.h>
34#include <linux/skbuff.h>
35#include <linux/slab.h>
36#include <linux/socket.h>
37#include <linux/spinlock.h>
38#include <linux/stddef.h>
39#include <linux/string.h>
40#include <linux/types.h>
41#include <uapi/linux/batadv_packet.h>
42#include <uapi/linux/batman_adv.h>
43
44#include "bat_algo.h"
45#include "bridge_loop_avoidance.h"
46#include "debugfs.h"
47#include "distributed-arp-table.h"
48#include "gateway_client.h"
49#include "hard-interface.h"
50#include "multicast.h"
51#include "network-coding.h"
52#include "originator.h"
53#include "send.h"
54#include "sysfs.h"
55#include "translation-table.h"
56
57/**
58 * batadv_skb_head_push() - Increase header size and move (push) head pointer
59 * @skb: packet buffer which should be modified
60 * @len: number of bytes to add
61 *
62 * Return: 0 on success or negative error number in case of failure
63 */
64int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
65{
66	int result;
67
68	/* TODO: We must check if we can release all references to non-payload
69	 * data using __skb_header_release in our skbs to allow skb_cow_header
70	 * to work optimally. This means that those skbs are not allowed to read
71	 * or write any data which is before the current position of skb->data
72	 * after that call and thus allow other skbs with the same data buffer
73	 * to write freely in that area.
74	 */
75	result = skb_cow_head(skb, len);
76	if (result < 0)
77		return result;
78
79	skb_push(skb, len);
80	return 0;
81}
82
83static int batadv_interface_open(struct net_device *dev)
84{
85	netif_start_queue(dev);
86	return 0;
87}
88
89static int batadv_interface_release(struct net_device *dev)
90{
91	netif_stop_queue(dev);
92	return 0;
93}
94
95/**
96 * batadv_sum_counter() - Sum the cpu-local counters for index 'idx'
97 * @bat_priv: the bat priv with all the soft interface information
98 * @idx: index of counter to sum up
99 *
100 * Return: sum of all cpu-local counters
101 */
102static u64 batadv_sum_counter(struct batadv_priv *bat_priv,  size_t idx)
103{
104	u64 *counters, sum = 0;
105	int cpu;
106
107	for_each_possible_cpu(cpu) {
108		counters = per_cpu_ptr(bat_priv->bat_counters, cpu);
109		sum += counters[idx];
110	}
111
112	return sum;
113}
114
115static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
116{
117	struct batadv_priv *bat_priv = netdev_priv(dev);
118	struct net_device_stats *stats = &dev->stats;
119
120	stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
121	stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
122	stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
123	stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
124	stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
125	return stats;
126}
127
128static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
129{
130	struct batadv_priv *bat_priv = netdev_priv(dev);
131	struct batadv_softif_vlan *vlan;
132	struct sockaddr *addr = p;
133	u8 old_addr[ETH_ALEN];
134
135	if (!is_valid_ether_addr(addr->sa_data))
136		return -EADDRNOTAVAIL;
137
138	ether_addr_copy(old_addr, dev->dev_addr);
139	ether_addr_copy(dev->dev_addr, addr->sa_data);
140
141	/* only modify transtable if it has been initialized before */
142	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
143		return 0;
144
145	rcu_read_lock();
146	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
147		batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
148				       "mac address changed", false);
149		batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
150				    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
151	}
152	rcu_read_unlock();
153
154	return 0;
155}
156
157static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
158{
159	struct batadv_priv *bat_priv = netdev_priv(dev);
160
161	/* check ranges */
162	if (new_mtu < 68 || new_mtu > batadv_hardif_min_mtu(dev))
163		return -EINVAL;
164
165	dev->mtu = new_mtu;
166	bat_priv->mtu_set_by_user = new_mtu;
167
168	return 0;
169}
170
171/**
172 * batadv_interface_set_rx_mode() - set the rx mode of a device
173 * @dev: registered network device to modify
174 *
175 * We do not actually need to set any rx filters for the virtual batman
176 * soft interface. However a dummy handler enables a user to set static
177 * multicast listeners for instance.
178 */
179static void batadv_interface_set_rx_mode(struct net_device *dev)
180{
181}
182
183static netdev_tx_t batadv_interface_tx(struct sk_buff *skb,
184				       struct net_device *soft_iface)
185{
186	struct ethhdr *ethhdr;
187	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
188	struct batadv_hard_iface *primary_if = NULL;
189	struct batadv_bcast_packet *bcast_packet;
190	static const u8 stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00,
191					      0x00, 0x00};
192	static const u8 ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00,
193					       0x00, 0x00};
194	enum batadv_dhcp_recipient dhcp_rcp = BATADV_DHCP_NO;
195	u8 *dst_hint = NULL, chaddr[ETH_ALEN];
196	struct vlan_ethhdr *vhdr;
197	unsigned int header_len = 0;
198	int data_len = skb->len, ret;
199	unsigned long brd_delay = 1;
200	bool do_bcast = false, client_added;
201	unsigned short vid;
202	u32 seqno;
203	int gw_mode;
204	enum batadv_forw_mode forw_mode = BATADV_FORW_SINGLE;
205	struct batadv_orig_node *mcast_single_orig = NULL;
206	int mcast_is_routable = 0;
207	int network_offset = ETH_HLEN;
208	__be16 proto;
209
210	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
211		goto dropped;
212
213	/* reset control block to avoid left overs from previous users */
214	memset(skb->cb, 0, sizeof(struct batadv_skb_cb));
215
216	netif_trans_update(soft_iface);
217	vid = batadv_get_vid(skb, 0);
218
219	skb_reset_mac_header(skb);
220	ethhdr = eth_hdr(skb);
221
222	proto = ethhdr->h_proto;
223
224	switch (ntohs(proto)) {
225	case ETH_P_8021Q:
226		if (!pskb_may_pull(skb, sizeof(*vhdr)))
227			goto dropped;
228		vhdr = vlan_eth_hdr(skb);
229		proto = vhdr->h_vlan_encapsulated_proto;
230
231		/* drop batman-in-batman packets to prevent loops */
232		if (proto != htons(ETH_P_BATMAN)) {
233			network_offset += VLAN_HLEN;
234			break;
235		}
236
237		fallthrough;
238	case ETH_P_BATMAN:
239		goto dropped;
240	}
241
242	skb_set_network_header(skb, network_offset);
243
244	if (batadv_bla_tx(bat_priv, skb, vid))
245		goto dropped;
246
247	/* skb->data might have been reallocated by batadv_bla_tx() */
248	ethhdr = eth_hdr(skb);
249
250	/* Register the client MAC in the transtable */
251	if (!is_multicast_ether_addr(ethhdr->h_source) &&
252	    !batadv_bla_is_loopdetect_mac(ethhdr->h_source)) {
253		client_added = batadv_tt_local_add(soft_iface, ethhdr->h_source,
254						   vid, skb->skb_iif,
255						   skb->mark);
256		if (!client_added)
257			goto dropped;
258	}
259
260	/* Snoop address candidates from DHCPACKs for early DAT filling */
261	batadv_dat_snoop_outgoing_dhcp_ack(bat_priv, skb, proto, vid);
262
263	/* don't accept stp packets. STP does not help in meshes.
264	 * better use the bridge loop avoidance ...
265	 *
266	 * The same goes for ECTP sent at least by some Cisco Switches,
267	 * it might confuse the mesh when used with bridge loop avoidance.
268	 */
269	if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
270		goto dropped;
271
272	if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
273		goto dropped;
274
275	gw_mode = atomic_read(&bat_priv->gw.mode);
276	if (is_multicast_ether_addr(ethhdr->h_dest)) {
277		/* if gw mode is off, broadcast every packet */
278		if (gw_mode == BATADV_GW_MODE_OFF) {
279			do_bcast = true;
280			goto send;
281		}
282
283		dhcp_rcp = batadv_gw_dhcp_recipient_get(skb, &header_len,
284							chaddr);
285		/* skb->data may have been modified by
286		 * batadv_gw_dhcp_recipient_get()
287		 */
288		ethhdr = eth_hdr(skb);
289		/* if gw_mode is on, broadcast any non-DHCP message.
290		 * All the DHCP packets are going to be sent as unicast
291		 */
292		if (dhcp_rcp == BATADV_DHCP_NO) {
293			do_bcast = true;
294			goto send;
295		}
296
297		if (dhcp_rcp == BATADV_DHCP_TO_CLIENT)
298			dst_hint = chaddr;
299		else if ((gw_mode == BATADV_GW_MODE_SERVER) &&
300			 (dhcp_rcp == BATADV_DHCP_TO_SERVER))
301			/* gateways should not forward any DHCP message if
302			 * directed to a DHCP server
303			 */
304			goto dropped;
305
306send:
307		if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) {
308			forw_mode = batadv_mcast_forw_mode(bat_priv, skb,
309							   &mcast_single_orig,
310							   &mcast_is_routable);
311			if (forw_mode == BATADV_FORW_NONE)
312				goto dropped;
313
314			if (forw_mode == BATADV_FORW_SINGLE ||
315			    forw_mode == BATADV_FORW_SOME)
316				do_bcast = false;
317		}
318	}
319
320	batadv_skb_set_priority(skb, 0);
321
322	/* ethernet packet should be broadcasted */
323	if (do_bcast) {
324		primary_if = batadv_primary_if_get_selected(bat_priv);
325		if (!primary_if)
326			goto dropped;
327
328		/* in case of ARP request, we do not immediately broadcasti the
329		 * packet, instead we first wait for DAT to try to retrieve the
330		 * correct ARP entry
331		 */
332		if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
333			brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
334
335		if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
336			goto dropped;
337
338		bcast_packet = (struct batadv_bcast_packet *)skb->data;
339		bcast_packet->version = BATADV_COMPAT_VERSION;
340		bcast_packet->ttl = BATADV_TTL;
341
342		/* batman packet type: broadcast */
343		bcast_packet->packet_type = BATADV_BCAST;
344		bcast_packet->reserved = 0;
345
346		/* hw address of first interface is the orig mac because only
347		 * this mac is known throughout the mesh
348		 */
349		ether_addr_copy(bcast_packet->orig,
350				primary_if->net_dev->dev_addr);
351
352		/* set broadcast sequence number */
353		seqno = atomic_inc_return(&bat_priv->bcast_seqno);
354		bcast_packet->seqno = htonl(seqno);
355
356		batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay, true);
357
358		/* a copy is stored in the bcast list, therefore removing
359		 * the original skb.
360		 */
361		consume_skb(skb);
362
363	/* unicast packet */
364	} else {
365		/* DHCP packets going to a server will use the GW feature */
366		if (dhcp_rcp == BATADV_DHCP_TO_SERVER) {
367			ret = batadv_gw_out_of_range(bat_priv, skb);
368			if (ret)
369				goto dropped;
370			ret = batadv_send_skb_via_gw(bat_priv, skb, vid);
371		} else if (mcast_single_orig) {
372			ret = batadv_mcast_forw_send_orig(bat_priv, skb, vid,
373							  mcast_single_orig);
374		} else if (forw_mode == BATADV_FORW_SOME) {
375			ret = batadv_mcast_forw_send(bat_priv, skb, vid,
376						     mcast_is_routable);
377		} else {
378			if (batadv_dat_snoop_outgoing_arp_request(bat_priv,
379								  skb))
380				goto dropped;
381
382			batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
383
384			ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
385						     vid);
386		}
387		if (ret != NET_XMIT_SUCCESS)
388			goto dropped_freed;
389	}
390
391	batadv_inc_counter(bat_priv, BATADV_CNT_TX);
392	batadv_add_counter(bat_priv, BATADV_CNT_TX_BYTES, data_len);
393	goto end;
394
395dropped:
396	kfree_skb(skb);
397dropped_freed:
398	batadv_inc_counter(bat_priv, BATADV_CNT_TX_DROPPED);
399end:
400	if (mcast_single_orig)
401		batadv_orig_node_put(mcast_single_orig);
402	if (primary_if)
403		batadv_hardif_put(primary_if);
404	return NETDEV_TX_OK;
405}
406
407/**
408 * batadv_interface_rx() - receive ethernet frame on local batman-adv interface
409 * @soft_iface: local interface which will receive the ethernet frame
410 * @skb: ethernet frame for @soft_iface
411 * @hdr_size: size of already parsed batman-adv header
412 * @orig_node: originator from which the batman-adv packet was sent
413 *
414 * Sends an ethernet frame to the receive path of the local @soft_iface.
415 * skb->data has still point to the batman-adv header with the size @hdr_size.
416 * The caller has to have parsed this header already and made sure that at least
417 * @hdr_size bytes are still available for pull in @skb.
418 *
419 * The packet may still get dropped. This can happen when the encapsulated
420 * ethernet frame is invalid or contains again an batman-adv packet. Also
421 * unicast packets will be dropped directly when it was sent between two
422 * isolated clients.
423 */
424void batadv_interface_rx(struct net_device *soft_iface,
425			 struct sk_buff *skb, int hdr_size,
426			 struct batadv_orig_node *orig_node)
427{
428	struct batadv_bcast_packet *batadv_bcast_packet;
429	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
430	struct vlan_ethhdr *vhdr;
431	struct ethhdr *ethhdr;
432	unsigned short vid;
433	int packet_type;
434
435	batadv_bcast_packet = (struct batadv_bcast_packet *)skb->data;
436	packet_type = batadv_bcast_packet->packet_type;
437
438	skb_pull_rcsum(skb, hdr_size);
439	skb_reset_mac_header(skb);
440
441	/* clean the netfilter state now that the batman-adv header has been
442	 * removed
443	 */
444	nf_reset_ct(skb);
445
446	if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
447		goto dropped;
448
449	vid = batadv_get_vid(skb, 0);
450	ethhdr = eth_hdr(skb);
451
452	switch (ntohs(ethhdr->h_proto)) {
453	case ETH_P_8021Q:
454		if (!pskb_may_pull(skb, VLAN_ETH_HLEN))
455			goto dropped;
456
457		vhdr = skb_vlan_eth_hdr(skb);
458
459		/* drop batman-in-batman packets to prevent loops */
460		if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN))
461			break;
462
463		fallthrough;
464	case ETH_P_BATMAN:
465		goto dropped;
466	}
467
468	/* skb->dev & skb->pkt_type are set here */
469	skb->protocol = eth_type_trans(skb, soft_iface);
470	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
471
472	batadv_inc_counter(bat_priv, BATADV_CNT_RX);
473	batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
474			   skb->len + ETH_HLEN);
475
476	/* Let the bridge loop avoidance check the packet. If will
477	 * not handle it, we can safely push it up.
478	 */
479	if (batadv_bla_rx(bat_priv, skb, vid, packet_type))
480		goto out;
481
482	if (orig_node)
483		batadv_tt_add_temporary_global_entry(bat_priv, orig_node,
484						     ethhdr->h_source, vid);
485
486	if (is_multicast_ether_addr(ethhdr->h_dest)) {
487		/* set the mark on broadcast packets if AP isolation is ON and
488		 * the packet is coming from an "isolated" client
489		 */
490		if (batadv_vlan_ap_isola_get(bat_priv, vid) &&
491		    batadv_tt_global_is_isolated(bat_priv, ethhdr->h_source,
492						 vid)) {
493			/* save bits in skb->mark not covered by the mask and
494			 * apply the mark on the rest
495			 */
496			skb->mark &= ~bat_priv->isolation_mark_mask;
497			skb->mark |= bat_priv->isolation_mark;
498		}
499	} else if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source,
500					 ethhdr->h_dest, vid)) {
501		goto dropped;
502	}
503
504	netif_rx(skb);
505	goto out;
506
507dropped:
508	kfree_skb(skb);
509out:
510	return;
511}
512
513/**
514 * batadv_softif_vlan_release() - release vlan from lists and queue for free
515 *  after rcu grace period
516 * @ref: kref pointer of the vlan object
517 */
518void batadv_softif_vlan_release(struct kref *ref)
519{
520	struct batadv_softif_vlan *vlan;
521
522	vlan = container_of(ref, struct batadv_softif_vlan, refcount);
523
524	spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock);
525	hlist_del_rcu(&vlan->list);
526	spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock);
527
528	kfree_rcu(vlan, rcu);
529}
530
531/**
532 * batadv_softif_vlan_get() - get the vlan object for a specific vid
533 * @bat_priv: the bat priv with all the soft interface information
534 * @vid: the identifier of the vlan object to retrieve
535 *
536 * Return: the private data of the vlan matching the vid passed as argument or
537 * NULL otherwise. The refcounter of the returned object is incremented by 1.
538 */
539struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv,
540						  unsigned short vid)
541{
542	struct batadv_softif_vlan *vlan_tmp, *vlan = NULL;
543
544	rcu_read_lock();
545	hlist_for_each_entry_rcu(vlan_tmp, &bat_priv->softif_vlan_list, list) {
546		if (vlan_tmp->vid != vid)
547			continue;
548
549		if (!kref_get_unless_zero(&vlan_tmp->refcount))
550			continue;
551
552		vlan = vlan_tmp;
553		break;
554	}
555	rcu_read_unlock();
556
557	return vlan;
558}
559
560/**
561 * batadv_softif_create_vlan() - allocate the needed resources for a new vlan
562 * @bat_priv: the bat priv with all the soft interface information
563 * @vid: the VLAN identifier
564 *
565 * Return: 0 on success, a negative error otherwise.
566 */
567int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
568{
569	struct batadv_softif_vlan *vlan;
570	int err;
571
572	spin_lock_bh(&bat_priv->softif_vlan_list_lock);
573
574	vlan = batadv_softif_vlan_get(bat_priv, vid);
575	if (vlan) {
576		batadv_softif_vlan_put(vlan);
577		spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
578		return -EEXIST;
579	}
580
581	vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
582	if (!vlan) {
583		spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
584		return -ENOMEM;
585	}
586
587	vlan->bat_priv = bat_priv;
588	vlan->vid = vid;
589	kref_init(&vlan->refcount);
590
591	atomic_set(&vlan->ap_isolation, 0);
592
593	kref_get(&vlan->refcount);
594	hlist_add_head_rcu(&vlan->list, &bat_priv->softif_vlan_list);
595	spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
596
597	/* batadv_sysfs_add_vlan cannot be in the spinlock section due to the
598	 * sleeping behavior of the sysfs functions and the fs_reclaim lock
599	 */
600	err = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
601	if (err) {
602		/* ref for the function */
603		batadv_softif_vlan_put(vlan);
604
605		/* ref for the list */
606		batadv_softif_vlan_put(vlan);
607		return err;
608	}
609
610	/* add a new TT local entry. This one will be marked with the NOPURGE
611	 * flag
612	 */
613	batadv_tt_local_add(bat_priv->soft_iface,
614			    bat_priv->soft_iface->dev_addr, vid,
615			    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
616
617	/* don't return reference to new softif_vlan */
618	batadv_softif_vlan_put(vlan);
619
620	return 0;
621}
622
623/**
624 * batadv_softif_destroy_vlan() - remove and destroy a softif_vlan object
625 * @bat_priv: the bat priv with all the soft interface information
626 * @vlan: the object to remove
627 */
628static void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
629				       struct batadv_softif_vlan *vlan)
630{
631	/* explicitly remove the associated TT local entry because it is marked
632	 * with the NOPURGE flag
633	 */
634	batadv_tt_local_remove(bat_priv, bat_priv->soft_iface->dev_addr,
635			       vlan->vid, "vlan interface destroyed", false);
636
637	batadv_sysfs_del_vlan(bat_priv, vlan);
638	batadv_softif_vlan_put(vlan);
639}
640
641/**
642 * batadv_interface_add_vid() - ndo_add_vid API implementation
643 * @dev: the netdev of the mesh interface
644 * @proto: protocol of the vlan id
645 * @vid: identifier of the new vlan
646 *
647 * Set up all the internal structures for handling the new vlan on top of the
648 * mesh interface
649 *
650 * Return: 0 on success or a negative error code in case of failure.
651 */
652static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
653				    unsigned short vid)
654{
655	struct batadv_priv *bat_priv = netdev_priv(dev);
656	struct batadv_softif_vlan *vlan;
657	int ret;
658
659	/* only 802.1Q vlans are supported.
660	 * batman-adv does not know how to handle other types
661	 */
662	if (proto != htons(ETH_P_8021Q))
663		return -EINVAL;
664
665	vid |= BATADV_VLAN_HAS_TAG;
666
667	/* if a new vlan is getting created and it already exists, it means that
668	 * it was not deleted yet. batadv_softif_vlan_get() increases the
669	 * refcount in order to revive the object.
670	 *
671	 * if it does not exist then create it.
672	 */
673	vlan = batadv_softif_vlan_get(bat_priv, vid);
674	if (!vlan)
675		return batadv_softif_create_vlan(bat_priv, vid);
676
677	/* recreate the sysfs object if it was already destroyed (and it should
678	 * be since we received a kill_vid() for this vlan
679	 */
680	if (!vlan->kobj) {
681		ret = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
682		if (ret) {
683			batadv_softif_vlan_put(vlan);
684			return ret;
685		}
686	}
687
688	/* add a new TT local entry. This one will be marked with the NOPURGE
689	 * flag. This must be added again, even if the vlan object already
690	 * exists, because the entry was deleted by kill_vid()
691	 */
692	batadv_tt_local_add(bat_priv->soft_iface,
693			    bat_priv->soft_iface->dev_addr, vid,
694			    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
695
696	return 0;
697}
698
699/**
700 * batadv_interface_kill_vid() - ndo_kill_vid API implementation
701 * @dev: the netdev of the mesh interface
702 * @proto: protocol of the vlan id
703 * @vid: identifier of the deleted vlan
704 *
705 * Destroy all the internal structures used to handle the vlan identified by vid
706 * on top of the mesh interface
707 *
708 * Return: 0 on success, -EINVAL if the specified prototype is not ETH_P_8021Q
709 * or -ENOENT if the specified vlan id wasn't registered.
710 */
711static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
712				     unsigned short vid)
713{
714	struct batadv_priv *bat_priv = netdev_priv(dev);
715	struct batadv_softif_vlan *vlan;
716
717	/* only 802.1Q vlans are supported. batman-adv does not know how to
718	 * handle other types
719	 */
720	if (proto != htons(ETH_P_8021Q))
721		return -EINVAL;
722
723	vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
724	if (!vlan)
725		return -ENOENT;
726
727	batadv_softif_destroy_vlan(bat_priv, vlan);
728
729	/* finally free the vlan object */
730	batadv_softif_vlan_put(vlan);
731
732	return 0;
733}
734
735/* batman-adv network devices have devices nesting below it and are a special
736 * "super class" of normal network devices; split their locks off into a
737 * separate class since they always nest.
738 */
739static struct lock_class_key batadv_netdev_xmit_lock_key;
740static struct lock_class_key batadv_netdev_addr_lock_key;
741
742/**
743 * batadv_set_lockdep_class_one() - Set lockdep class for a single tx queue
744 * @dev: device which owns the tx queue
745 * @txq: tx queue to modify
746 * @_unused: always NULL
747 */
748static void batadv_set_lockdep_class_one(struct net_device *dev,
749					 struct netdev_queue *txq,
750					 void *_unused)
751{
752	lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
753}
754
755/**
756 * batadv_set_lockdep_class() - Set txq and addr_list lockdep class
757 * @dev: network device to modify
758 */
759static void batadv_set_lockdep_class(struct net_device *dev)
760{
761	lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
762	netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
763}
764
765/**
766 * batadv_softif_init_late() - late stage initialization of soft interface
767 * @dev: registered network device to modify
768 *
769 * Return: error code on failures
770 */
771static int batadv_softif_init_late(struct net_device *dev)
772{
773	struct batadv_priv *bat_priv;
774	u32 random_seqno;
775	int ret;
776	size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
777
778	batadv_set_lockdep_class(dev);
779
780	bat_priv = netdev_priv(dev);
781	bat_priv->soft_iface = dev;
782
783	/* batadv_interface_stats() needs to be available as soon as
784	 * register_netdevice() has been called
785	 */
786	bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(u64));
787	if (!bat_priv->bat_counters)
788		return -ENOMEM;
789
790	atomic_set(&bat_priv->aggregated_ogms, 1);
791	atomic_set(&bat_priv->bonding, 0);
792#ifdef CONFIG_BATMAN_ADV_BLA
793	atomic_set(&bat_priv->bridge_loop_avoidance, 1);
794#endif
795#ifdef CONFIG_BATMAN_ADV_DAT
796	atomic_set(&bat_priv->distributed_arp_table, 1);
797#endif
798#ifdef CONFIG_BATMAN_ADV_MCAST
799	atomic_set(&bat_priv->multicast_mode, 1);
800	atomic_set(&bat_priv->multicast_fanout, 16);
801	atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
802	atomic_set(&bat_priv->mcast.num_want_all_ipv4, 0);
803	atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
804#endif
805	atomic_set(&bat_priv->gw.mode, BATADV_GW_MODE_OFF);
806	atomic_set(&bat_priv->gw.bandwidth_down, 100);
807	atomic_set(&bat_priv->gw.bandwidth_up, 20);
808	atomic_set(&bat_priv->orig_interval, 1000);
809	atomic_set(&bat_priv->hop_penalty, 30);
810#ifdef CONFIG_BATMAN_ADV_DEBUG
811	atomic_set(&bat_priv->log_level, 0);
812#endif
813	atomic_set(&bat_priv->fragmentation, 1);
814	atomic_set(&bat_priv->packet_size_max, ETH_DATA_LEN);
815	atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
816	atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
817
818	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
819	atomic_set(&bat_priv->bcast_seqno, 1);
820	atomic_set(&bat_priv->tt.vn, 0);
821	atomic_set(&bat_priv->tt.local_changes, 0);
822	atomic_set(&bat_priv->tt.ogm_append_cnt, 0);
823#ifdef CONFIG_BATMAN_ADV_BLA
824	atomic_set(&bat_priv->bla.num_requests, 0);
825#endif
826	atomic_set(&bat_priv->tp_num, 0);
827
828	bat_priv->tt.last_changeset = NULL;
829	bat_priv->tt.last_changeset_len = 0;
830	bat_priv->isolation_mark = 0;
831	bat_priv->isolation_mark_mask = 0;
832
833	/* randomize initial seqno to avoid collision */
834	get_random_bytes(&random_seqno, sizeof(random_seqno));
835	atomic_set(&bat_priv->frag_seqno, random_seqno);
836
837	bat_priv->primary_if = NULL;
838
839	batadv_nc_init_bat_priv(bat_priv);
840
841	ret = batadv_algo_select(bat_priv, batadv_routing_algo);
842	if (ret < 0)
843		goto free_bat_counters;
844
845	ret = batadv_debugfs_add_meshif(dev);
846	if (ret < 0)
847		goto free_bat_counters;
848
849	ret = batadv_mesh_init(dev);
850	if (ret < 0)
851		goto unreg_debugfs;
852
853	return 0;
854
855unreg_debugfs:
856	batadv_debugfs_del_meshif(dev);
857free_bat_counters:
858	free_percpu(bat_priv->bat_counters);
859	bat_priv->bat_counters = NULL;
860
861	return ret;
862}
863
864/**
865 * batadv_softif_slave_add() - Add a slave interface to a batadv_soft_interface
866 * @dev: batadv_soft_interface used as master interface
867 * @slave_dev: net_device which should become the slave interface
868 * @extack: extended ACK report struct
869 *
870 * Return: 0 if successful or error otherwise.
871 */
872static int batadv_softif_slave_add(struct net_device *dev,
873				   struct net_device *slave_dev,
874				   struct netlink_ext_ack *extack)
875{
876	struct batadv_hard_iface *hard_iface;
877	struct net *net = dev_net(dev);
878	int ret = -EINVAL;
879
880	hard_iface = batadv_hardif_get_by_netdev(slave_dev);
881	if (!hard_iface || hard_iface->soft_iface)
882		goto out;
883
884	ret = batadv_hardif_enable_interface(hard_iface, net, dev->name);
885
886out:
887	if (hard_iface)
888		batadv_hardif_put(hard_iface);
889	return ret;
890}
891
892/**
893 * batadv_softif_slave_del() - Delete a slave iface from a batadv_soft_interface
894 * @dev: batadv_soft_interface used as master interface
895 * @slave_dev: net_device which should be removed from the master interface
896 *
897 * Return: 0 if successful or error otherwise.
898 */
899static int batadv_softif_slave_del(struct net_device *dev,
900				   struct net_device *slave_dev)
901{
902	struct batadv_hard_iface *hard_iface;
903	int ret = -EINVAL;
904
905	hard_iface = batadv_hardif_get_by_netdev(slave_dev);
906
907	if (!hard_iface || hard_iface->soft_iface != dev)
908		goto out;
909
910	batadv_hardif_disable_interface(hard_iface, BATADV_IF_CLEANUP_KEEP);
911	ret = 0;
912
913out:
914	if (hard_iface)
915		batadv_hardif_put(hard_iface);
916	return ret;
917}
918
919static const struct net_device_ops batadv_netdev_ops = {
920	.ndo_init = batadv_softif_init_late,
921	.ndo_open = batadv_interface_open,
922	.ndo_stop = batadv_interface_release,
923	.ndo_get_stats = batadv_interface_stats,
924	.ndo_vlan_rx_add_vid = batadv_interface_add_vid,
925	.ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
926	.ndo_set_mac_address = batadv_interface_set_mac_addr,
927	.ndo_change_mtu = batadv_interface_change_mtu,
928	.ndo_set_rx_mode = batadv_interface_set_rx_mode,
929	.ndo_start_xmit = batadv_interface_tx,
930	.ndo_validate_addr = eth_validate_addr,
931	.ndo_add_slave = batadv_softif_slave_add,
932	.ndo_del_slave = batadv_softif_slave_del,
933};
934
935static void batadv_get_drvinfo(struct net_device *dev,
936			       struct ethtool_drvinfo *info)
937{
938	strscpy(info->driver, "B.A.T.M.A.N. advanced", sizeof(info->driver));
939	strscpy(info->version, BATADV_SOURCE_VERSION, sizeof(info->version));
940	strscpy(info->fw_version, "N/A", sizeof(info->fw_version));
941	strscpy(info->bus_info, "batman", sizeof(info->bus_info));
942}
943
944/* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
945 * Declare each description string in struct.name[] to get fixed sized buffer
946 * and compile time checking for strings longer than ETH_GSTRING_LEN.
947 */
948static const struct {
949	const char name[ETH_GSTRING_LEN];
950} batadv_counters_strings[] = {
951	{ "tx" },
952	{ "tx_bytes" },
953	{ "tx_dropped" },
954	{ "rx" },
955	{ "rx_bytes" },
956	{ "forward" },
957	{ "forward_bytes" },
958	{ "mgmt_tx" },
959	{ "mgmt_tx_bytes" },
960	{ "mgmt_rx" },
961	{ "mgmt_rx_bytes" },
962	{ "frag_tx" },
963	{ "frag_tx_bytes" },
964	{ "frag_rx" },
965	{ "frag_rx_bytes" },
966	{ "frag_fwd" },
967	{ "frag_fwd_bytes" },
968	{ "tt_request_tx" },
969	{ "tt_request_rx" },
970	{ "tt_response_tx" },
971	{ "tt_response_rx" },
972	{ "tt_roam_adv_tx" },
973	{ "tt_roam_adv_rx" },
974#ifdef CONFIG_BATMAN_ADV_DAT
975	{ "dat_get_tx" },
976	{ "dat_get_rx" },
977	{ "dat_put_tx" },
978	{ "dat_put_rx" },
979	{ "dat_cached_reply_tx" },
980#endif
981#ifdef CONFIG_BATMAN_ADV_NC
982	{ "nc_code" },
983	{ "nc_code_bytes" },
984	{ "nc_recode" },
985	{ "nc_recode_bytes" },
986	{ "nc_buffer" },
987	{ "nc_decode" },
988	{ "nc_decode_bytes" },
989	{ "nc_decode_failed" },
990	{ "nc_sniffed" },
991#endif
992};
993
994static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data)
995{
996	if (stringset == ETH_SS_STATS)
997		memcpy(data, batadv_counters_strings,
998		       sizeof(batadv_counters_strings));
999}
1000
1001static void batadv_get_ethtool_stats(struct net_device *dev,
1002				     struct ethtool_stats *stats, u64 *data)
1003{
1004	struct batadv_priv *bat_priv = netdev_priv(dev);
1005	int i;
1006
1007	for (i = 0; i < BATADV_CNT_NUM; i++)
1008		data[i] = batadv_sum_counter(bat_priv, i);
1009}
1010
1011static int batadv_get_sset_count(struct net_device *dev, int stringset)
1012{
1013	if (stringset == ETH_SS_STATS)
1014		return BATADV_CNT_NUM;
1015
1016	return -EOPNOTSUPP;
1017}
1018
1019static const struct ethtool_ops batadv_ethtool_ops = {
1020	.get_drvinfo = batadv_get_drvinfo,
1021	.get_link = ethtool_op_get_link,
1022	.get_strings = batadv_get_strings,
1023	.get_ethtool_stats = batadv_get_ethtool_stats,
1024	.get_sset_count = batadv_get_sset_count,
1025};
1026
1027/**
1028 * batadv_softif_free() - Deconstructor of batadv_soft_interface
1029 * @dev: Device to cleanup and remove
1030 */
1031static void batadv_softif_free(struct net_device *dev)
1032{
1033	batadv_debugfs_del_meshif(dev);
1034	batadv_mesh_free(dev);
1035
1036	/* some scheduled RCU callbacks need the bat_priv struct to accomplish
1037	 * their tasks. Wait for them all to be finished before freeing the
1038	 * netdev and its private data (bat_priv)
1039	 */
1040	rcu_barrier();
1041}
1042
1043/**
1044 * batadv_softif_init_early() - early stage initialization of soft interface
1045 * @dev: registered network device to modify
1046 */
1047static void batadv_softif_init_early(struct net_device *dev)
1048{
1049	ether_setup(dev);
1050
1051	dev->netdev_ops = &batadv_netdev_ops;
1052	dev->needs_free_netdev = true;
1053	dev->priv_destructor = batadv_softif_free;
1054	dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_NETNS_LOCAL;
1055	dev->features |= NETIF_F_LLTX;
1056	dev->priv_flags |= IFF_NO_QUEUE;
1057
1058	/* can't call min_mtu, because the needed variables
1059	 * have not been initialized yet
1060	 */
1061	dev->mtu = ETH_DATA_LEN;
1062
1063	/* generate random address */
1064	eth_hw_addr_random(dev);
1065
1066	dev->ethtool_ops = &batadv_ethtool_ops;
1067}
1068
1069/**
1070 * batadv_softif_create() - Create and register soft interface
1071 * @net: the applicable net namespace
1072 * @name: name of the new soft interface
1073 *
1074 * Return: newly allocated soft_interface, NULL on errors
1075 */
1076struct net_device *batadv_softif_create(struct net *net, const char *name)
1077{
1078	struct net_device *soft_iface;
1079	int ret;
1080
1081	soft_iface = alloc_netdev(sizeof(struct batadv_priv), name,
1082				  NET_NAME_UNKNOWN, batadv_softif_init_early);
1083	if (!soft_iface)
1084		return NULL;
1085
1086	dev_net_set(soft_iface, net);
1087
1088	soft_iface->rtnl_link_ops = &batadv_link_ops;
1089
1090	ret = register_netdevice(soft_iface);
1091	if (ret < 0) {
1092		pr_err("Unable to register the batman interface '%s': %i\n",
1093		       name, ret);
1094		free_netdev(soft_iface);
1095		return NULL;
1096	}
1097
1098	return soft_iface;
1099}
1100
1101/**
1102 * batadv_softif_destroy_sysfs() - deletion of batadv_soft_interface via sysfs
1103 * @soft_iface: the to-be-removed batman-adv interface
1104 */
1105void batadv_softif_destroy_sysfs(struct net_device *soft_iface)
1106{
1107	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
1108	struct batadv_softif_vlan *vlan;
1109
1110	ASSERT_RTNL();
1111
1112	/* destroy the "untagged" VLAN */
1113	vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
1114	if (vlan) {
1115		batadv_softif_destroy_vlan(bat_priv, vlan);
1116		batadv_softif_vlan_put(vlan);
1117	}
1118
1119	batadv_sysfs_del_meshif(soft_iface);
1120	unregister_netdevice(soft_iface);
1121}
1122
1123/**
1124 * batadv_softif_destroy_netlink() - deletion of batadv_soft_interface via
1125 *  netlink
1126 * @soft_iface: the to-be-removed batman-adv interface
1127 * @head: list pointer
1128 */
1129static void batadv_softif_destroy_netlink(struct net_device *soft_iface,
1130					  struct list_head *head)
1131{
1132	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
1133	struct batadv_hard_iface *hard_iface;
1134	struct batadv_softif_vlan *vlan;
1135
1136	list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
1137		if (hard_iface->soft_iface == soft_iface)
1138			batadv_hardif_disable_interface(hard_iface,
1139							BATADV_IF_CLEANUP_KEEP);
1140	}
1141
1142	/* destroy the "untagged" VLAN */
1143	vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
1144	if (vlan) {
1145		batadv_softif_destroy_vlan(bat_priv, vlan);
1146		batadv_softif_vlan_put(vlan);
1147	}
1148
1149	batadv_sysfs_del_meshif(soft_iface);
1150	unregister_netdevice_queue(soft_iface, head);
1151}
1152
1153/**
1154 * batadv_softif_is_valid() - Check whether device is a batadv soft interface
1155 * @net_dev: device which should be checked
1156 *
1157 * Return: true when net_dev is a batman-adv interface, false otherwise
1158 */
1159bool batadv_softif_is_valid(const struct net_device *net_dev)
1160{
1161	if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
1162		return true;
1163
1164	return false;
1165}
1166
1167struct rtnl_link_ops batadv_link_ops __read_mostly = {
1168	.kind		= "batadv",
1169	.priv_size	= sizeof(struct batadv_priv),
1170	.setup		= batadv_softif_init_early,
1171	.dellink	= batadv_softif_destroy_netlink,
1172};
1173