1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) B.A.T.M.A.N. contributors:
3 *
4 * Marek Lindner, Simon Wunderlich
5 */
6
7 #include "mesh-interface.h"
8 #include "main.h"
9
10 #include <linux/atomic.h>
11 #include <linux/bug.h>
12 #include <linux/byteorder/generic.h>
13 #include <linux/cache.h>
14 #include <linux/compiler.h>
15 #include <linux/container_of.h>
16 #include <linux/cpumask.h>
17 #include <linux/errno.h>
18 #include <linux/etherdevice.h>
19 #include <linux/ethtool.h>
20 #include <linux/gfp.h>
21 #include <linux/if_ether.h>
22 #include <linux/if_vlan.h>
23 #include <linux/jiffies.h>
24 #include <linux/kref.h>
25 #include <linux/list.h>
26 #include <linux/lockdep.h>
27 #include <linux/netdevice.h>
28 #include <linux/netlink.h>
29 #include <linux/percpu.h>
30 #include <linux/random.h>
31 #include <linux/rculist.h>
32 #include <linux/rcupdate.h>
33 #include <linux/skbuff.h>
34 #include <linux/slab.h>
35 #include <linux/socket.h>
36 #include <linux/spinlock.h>
37 #include <linux/stddef.h>
38 #include <linux/string.h>
39 #include <linux/types.h>
40 #include <linux/utsname.h>
41 #include <net/netlink.h>
42 #include <net/rtnetlink.h>
43 #include <uapi/linux/batadv_packet.h>
44 #include <uapi/linux/batman_adv.h>
45
46 #include "bat_algo.h"
47 #include "bridge_loop_avoidance.h"
48 #include "distributed-arp-table.h"
49 #include "gateway_client.h"
50 #include "hard-interface.h"
51 #include "multicast.h"
52 #include "send.h"
53 #include "translation-table.h"
54
55 /**
56 * batadv_skb_head_push() - Increase header size and move (push) head pointer
57 * @skb: packet buffer which should be modified
58 * @len: number of bytes to add
59 *
60 * Warning: This function may reallocate the skb data buffer via
61 * skb_cow_head()/... Any pointer into the skb data (e.g. obtained
62 * from skb->data or eth_hdr()) before this call must be considered
63 * invalid afterwards and has to be reacquired.
64 *
65 * Return: 0 on success or negative error number in case of failure
66 */
batadv_skb_head_push(struct sk_buff * skb,unsigned int len)67 int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
68 {
69 int result;
70
71 /* TODO: We must check if we can release all references to non-payload
72 * data using __skb_header_release in our skbs to allow skb_cow_header
73 * to work optimally. This means that those skbs are not allowed to read
74 * or write any data which is before the current position of skb->data
75 * after that call and thus allow other skbs with the same data buffer
76 * to write freely in that area.
77 */
78 result = skb_cow_head(skb, len);
79 if (result < 0)
80 return result;
81
82 skb_push(skb, len);
83 return 0;
84 }
85
86 /**
87 * batadv_sum_counter() - Sum the cpu-local counters for index 'idx'
88 * @bat_priv: the bat priv with all the mesh interface information
89 * @idx: index of counter to sum up
90 *
91 * Return: sum of all cpu-local counters
92 */
batadv_sum_counter(struct batadv_priv * bat_priv,size_t idx)93 static u64 batadv_sum_counter(struct batadv_priv *bat_priv, size_t idx)
94 {
95 u64 *counters;
96 u64 sum = 0;
97 int cpu;
98
99 for_each_possible_cpu(cpu) {
100 counters = per_cpu_ptr(bat_priv->bat_counters, cpu);
101 sum += counters[idx];
102 }
103
104 return sum;
105 }
106
107 /**
108 * batadv_interface_stats() - return netdev stats for a mesh interface
109 * @dev: the mesh interface to query
110 *
111 * Aggregate the per-CPU traffic counters into the standard netdev stats
112 * structure.
113 *
114 * Return: pointer to the populated net_device_stats structure
115 */
batadv_interface_stats(struct net_device * dev)116 static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
117 {
118 struct batadv_priv *bat_priv = netdev_priv(dev);
119 struct net_device_stats *stats = &dev->stats;
120
121 stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
122 stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
123 stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
124 stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
125 stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
126 return stats;
127 }
128
129 /**
130 * batadv_interface_set_mac_addr() - change the MAC address of a mesh
131 * interface
132 * @dev: the mesh interface to modify
133 * @p: pointer to a struct sockaddr holding the new MAC address
134 *
135 * Replace the MAC address of the mesh interface. If the mesh is already
136 * active, also update the local translation table entries for all configured
137 * VLANs so that the new MAC is announced and the old one is removed.
138 *
139 * Return: 0 on success or negative error number in case of failure
140 */
batadv_interface_set_mac_addr(struct net_device * dev,void * p)141 static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
142 {
143 struct batadv_priv *bat_priv = netdev_priv(dev);
144 struct batadv_meshif_vlan *vlan;
145 struct sockaddr *addr = p;
146 u8 old_addr[ETH_ALEN];
147
148 if (!is_valid_ether_addr(addr->sa_data))
149 return -EADDRNOTAVAIL;
150
151 ether_addr_copy(old_addr, dev->dev_addr);
152 eth_hw_addr_set(dev, addr->sa_data);
153
154 /* only modify transtable if it has been initialized before */
155 if (READ_ONCE(bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
156 return 0;
157
158 rcu_read_lock();
159 hlist_for_each_entry_rcu(vlan, &bat_priv->meshif_vlan_list, list) {
160 batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
161 "mac address changed", false);
162 batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
163 BATADV_NULL_IFINDEX, BATADV_NO_MARK);
164 }
165 rcu_read_unlock();
166
167 return 0;
168 }
169
170 /**
171 * batadv_interface_change_mtu() - change the MTU of a mesh interface
172 * @dev: the mesh interface to modify
173 * @new_mtu: requested new MTU value
174 *
175 * Validate that @new_mtu fits within the range supported by the configured
176 * hard interfaces and remember it as the user-configured MTU.
177 *
178 * Return: 0 on success or -EINVAL if @new_mtu is out of range
179 */
batadv_interface_change_mtu(struct net_device * dev,int new_mtu)180 static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
181 {
182 struct batadv_priv *bat_priv = netdev_priv(dev);
183
184 /* check ranges */
185 if (new_mtu < ETH_MIN_MTU || new_mtu > batadv_hardif_min_mtu(dev))
186 return -EINVAL;
187
188 WRITE_ONCE(dev->mtu, new_mtu);
189 bat_priv->mtu_set_by_user = new_mtu;
190
191 return 0;
192 }
193
194 /**
195 * batadv_interface_set_rx_mode() - set the rx mode of a device
196 * @dev: registered network device to modify
197 *
198 * We do not actually need to set any rx filters for the virtual batman
199 * mesh interface. However a dummy handler enables a user to set static
200 * multicast listeners for instance.
201 */
batadv_interface_set_rx_mode(struct net_device * dev)202 static void batadv_interface_set_rx_mode(struct net_device *dev)
203 {
204 }
205
206 /**
207 * batadv_interface_tx() - transmit a frame on a mesh interface
208 * @skb: the frame to send
209 * @mesh_iface: the mesh interface the frame was queued on
210 *
211 * Return: NETDEV_TX_OK on success
212 */
batadv_interface_tx(struct sk_buff * skb,struct net_device * mesh_iface)213 static netdev_tx_t batadv_interface_tx(struct sk_buff *skb,
214 struct net_device *mesh_iface)
215 {
216 static const u8 ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00, 0x00, 0x00};
217 static const u8 stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x00};
218 struct batadv_priv *bat_priv = netdev_priv(mesh_iface);
219 enum batadv_dhcp_recipient dhcp_rcp = BATADV_DHCP_NO;
220 enum batadv_forw_mode forw_mode = BATADV_FORW_BCAST;
221 struct batadv_hard_iface *primary_if = NULL;
222 struct batadv_bcast_packet *bcast_packet;
223 int network_offset = ETH_HLEN;
224 unsigned int header_len = 0;
225 unsigned long brd_delay = 0;
226 int mcast_is_routable = 0;
227 struct vlan_ethhdr *vhdr;
228 int data_len = skb->len;
229 struct ethhdr *ethhdr;
230 bool do_bcast = false;
231 u8 *dst_hint = NULL;
232 u8 chaddr[ETH_ALEN];
233 unsigned short vid;
234 bool client_added;
235 __be16 proto;
236 int gw_mode;
237 u32 seqno;
238 int ret;
239
240 if (READ_ONCE(bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
241 goto dropped;
242
243 if (!pskb_may_pull(skb, ETH_HLEN))
244 goto dropped;
245
246 /* reset control block to avoid left overs from previous users */
247 memset(skb->cb, 0, sizeof(struct batadv_skb_cb));
248
249 netif_trans_update(mesh_iface);
250 vid = batadv_get_vid(skb, 0);
251
252 skb_reset_mac_header(skb);
253 ethhdr = eth_hdr(skb);
254
255 proto = ethhdr->h_proto;
256
257 switch (ntohs(proto)) {
258 case ETH_P_8021Q:
259 if (!pskb_may_pull(skb, sizeof(*vhdr)))
260 goto dropped;
261 vhdr = vlan_eth_hdr(skb);
262 proto = vhdr->h_vlan_encapsulated_proto;
263
264 /* drop batman-in-batman packets to prevent loops */
265 if (proto != htons(ETH_P_BATMAN)) {
266 network_offset += VLAN_HLEN;
267 break;
268 }
269
270 fallthrough;
271 case ETH_P_BATMAN:
272 goto dropped;
273 }
274
275 skb_set_network_header(skb, network_offset);
276
277 if (batadv_bla_tx(bat_priv, skb, vid))
278 goto dropped;
279
280 /* skb->data might have been reallocated by batadv_bla_tx() */
281 ethhdr = eth_hdr(skb);
282
283 /* Register the client MAC in the transtable */
284 if (!is_multicast_ether_addr(ethhdr->h_source) &&
285 !batadv_bla_is_loopdetect_mac(ethhdr->h_source)) {
286 client_added = batadv_tt_local_add(mesh_iface, ethhdr->h_source,
287 vid, skb->skb_iif,
288 skb->mark);
289 if (!client_added)
290 goto dropped;
291 }
292
293 /* Snoop address candidates from DHCPACKs for early DAT filling */
294 batadv_dat_snoop_outgoing_dhcp_ack(bat_priv, skb, proto, vid);
295
296 /* don't accept stp packets. STP does not help in meshes.
297 * better use the bridge loop avoidance ...
298 *
299 * The same goes for ECTP sent at least by some Cisco Switches,
300 * it might confuse the mesh when used with bridge loop avoidance.
301 */
302 if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
303 goto dropped;
304
305 if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
306 goto dropped;
307
308 batadv_skb_set_priority(skb, 0);
309
310 gw_mode = READ_ONCE(bat_priv->gw.mode);
311 if (is_multicast_ether_addr(ethhdr->h_dest)) {
312 /* if gw mode is off, broadcast every packet */
313 if (gw_mode == BATADV_GW_MODE_OFF) {
314 do_bcast = true;
315 goto send;
316 }
317
318 dhcp_rcp = batadv_gw_dhcp_recipient_get(skb, &header_len,
319 chaddr);
320 /* skb->data may have been modified by
321 * batadv_gw_dhcp_recipient_get()
322 */
323 ethhdr = eth_hdr(skb);
324 /* if gw_mode is on, broadcast any non-DHCP message.
325 * All the DHCP packets are going to be sent as unicast
326 */
327 if (dhcp_rcp == BATADV_DHCP_NO) {
328 do_bcast = true;
329 goto send;
330 }
331
332 if (dhcp_rcp == BATADV_DHCP_TO_CLIENT)
333 dst_hint = chaddr;
334 else if ((gw_mode == BATADV_GW_MODE_SERVER) &&
335 (dhcp_rcp == BATADV_DHCP_TO_SERVER))
336 /* gateways should not forward any DHCP message if
337 * directed to a DHCP server
338 */
339 goto dropped;
340
341 send:
342 if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) {
343 /* WARNING batadv_mcast_forw_mode might add more headers
344 * in front of the skb. and might even reallocate the skb
345 */
346 forw_mode = batadv_mcast_forw_mode(bat_priv, skb, vid,
347 &mcast_is_routable);
348 switch (forw_mode) {
349 case BATADV_FORW_BCAST:
350 break;
351 case BATADV_FORW_UCASTS:
352 case BATADV_FORW_MCAST:
353 do_bcast = false;
354 break;
355 case BATADV_FORW_NONE:
356 fallthrough;
357 default:
358 goto dropped;
359 }
360 }
361 }
362
363 /* ethernet packet should be broadcasted */
364 if (do_bcast) {
365 primary_if = batadv_primary_if_get_selected(bat_priv);
366 if (!primary_if)
367 goto dropped;
368
369 /* in case of ARP request, we do not immediately broadcasti the
370 * packet, instead we first wait for DAT to try to retrieve the
371 * correct ARP entry
372 */
373 if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
374 brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
375
376 if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
377 goto dropped;
378
379 bcast_packet = (struct batadv_bcast_packet *)skb->data;
380 bcast_packet->version = BATADV_COMPAT_VERSION;
381 bcast_packet->ttl = BATADV_TTL - 1;
382
383 /* batman packet type: broadcast */
384 bcast_packet->packet_type = BATADV_BCAST;
385 bcast_packet->reserved = 0;
386
387 /* hw address of first interface is the orig mac because only
388 * this mac is known throughout the mesh
389 */
390 ether_addr_copy(bcast_packet->orig,
391 primary_if->net_dev->dev_addr);
392
393 /* set broadcast sequence number */
394 seqno = atomic_inc_return(&bat_priv->bcast_seqno);
395 bcast_packet->seqno = htonl(seqno);
396
397 batadv_send_bcast_packet(bat_priv, skb, brd_delay, true);
398 /* unicast packet */
399 } else {
400 /* DHCP packets going to a server will use the GW feature */
401 if (dhcp_rcp == BATADV_DHCP_TO_SERVER) {
402 ret = batadv_gw_out_of_range(bat_priv, skb);
403 if (ret)
404 goto dropped;
405 ret = batadv_send_skb_via_gw(bat_priv, skb, vid);
406 } else if (forw_mode == BATADV_FORW_UCASTS) {
407 ret = batadv_mcast_forw_send(bat_priv, skb, vid,
408 mcast_is_routable);
409 } else if (forw_mode == BATADV_FORW_MCAST) {
410 ret = batadv_mcast_forw_mcsend(bat_priv, skb);
411 } else {
412 if (batadv_dat_snoop_outgoing_arp_request(bat_priv,
413 skb))
414 goto dropped;
415
416 batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
417
418 ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
419 vid);
420 }
421 if (ret != NET_XMIT_SUCCESS)
422 goto dropped_freed;
423 }
424
425 batadv_inc_counter(bat_priv, BATADV_CNT_TX);
426 batadv_add_counter(bat_priv, BATADV_CNT_TX_BYTES, data_len);
427 goto end;
428
429 dropped:
430 kfree_skb(skb);
431 dropped_freed:
432 batadv_inc_counter(bat_priv, BATADV_CNT_TX_DROPPED);
433 end:
434 batadv_hardif_put(primary_if);
435 return NETDEV_TX_OK;
436 }
437
438 /**
439 * batadv_interface_rx() - receive ethernet frame on local batman-adv interface
440 * @mesh_iface: local interface which will receive the ethernet frame
441 * @skb: ethernet frame for @mesh_iface
442 * @hdr_size: size of already parsed batman-adv header
443 * @orig_node: originator from which the batman-adv packet was sent
444 *
445 * Sends an ethernet frame to the receive path of the local @mesh_iface.
446 * skb->data must still point to the batman-adv header with the size @hdr_size.
447 * The caller has to have parsed this header already and made sure that at least
448 * @hdr_size bytes are still available for pull in @skb.
449 *
450 * The packet may still get dropped. This can happen when the encapsulated
451 * ethernet frame is invalid or contains again a batman-adv packet. Also
452 * unicast packets will be dropped directly when they were sent between two
453 * isolated clients.
454 */
batadv_interface_rx(struct net_device * mesh_iface,struct sk_buff * skb,int hdr_size,struct batadv_orig_node * orig_node)455 void batadv_interface_rx(struct net_device *mesh_iface,
456 struct sk_buff *skb, int hdr_size,
457 struct batadv_orig_node *orig_node)
458 {
459 struct batadv_priv *bat_priv = netdev_priv(mesh_iface);
460 struct batadv_bcast_packet *batadv_bcast_packet;
461 struct vlan_ethhdr *vhdr;
462 struct ethhdr *ethhdr;
463 unsigned short vid;
464 int packet_type;
465
466 batadv_bcast_packet = (struct batadv_bcast_packet *)skb->data;
467 packet_type = batadv_bcast_packet->packet_type;
468
469 skb_pull_rcsum(skb, hdr_size);
470 skb_reset_mac_header(skb);
471
472 /* clean the netfilter state now that the batman-adv header has been
473 * removed
474 */
475 nf_reset_ct(skb);
476
477 if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
478 goto dropped;
479
480 vid = batadv_get_vid(skb, 0);
481 ethhdr = eth_hdr(skb);
482
483 switch (ntohs(ethhdr->h_proto)) {
484 case ETH_P_8021Q:
485 if (!pskb_may_pull(skb, VLAN_ETH_HLEN))
486 goto dropped;
487
488 ethhdr = eth_hdr(skb);
489 vhdr = skb_vlan_eth_hdr(skb);
490
491 /* drop batman-in-batman packets to prevent loops */
492 if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN))
493 break;
494
495 fallthrough;
496 case ETH_P_BATMAN:
497 goto dropped;
498 }
499
500 /* skb->dev & skb->pkt_type are set here */
501 skb->protocol = eth_type_trans(skb, mesh_iface);
502 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
503
504 batadv_inc_counter(bat_priv, BATADV_CNT_RX);
505 batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
506 skb->len + ETH_HLEN);
507
508 /* Let the bridge loop avoidance check the packet. If will
509 * not handle it, we can safely push it up.
510 */
511 if (batadv_bla_rx(bat_priv, skb, vid, packet_type))
512 goto out;
513
514 if (orig_node)
515 batadv_tt_add_temporary_global_entry(bat_priv, orig_node,
516 ethhdr->h_source, vid);
517
518 if (is_multicast_ether_addr(ethhdr->h_dest)) {
519 /* set the mark on broadcast packets if AP isolation is ON and
520 * the packet is coming from an "isolated" client
521 */
522 if (batadv_vlan_ap_isola_get(bat_priv, vid) &&
523 batadv_tt_global_is_isolated(bat_priv, ethhdr->h_source,
524 vid)) {
525 /* save bits in skb->mark not covered by the mask and
526 * apply the mark on the rest
527 */
528 skb->mark &= ~bat_priv->isolation_mark_mask;
529 skb->mark |= bat_priv->isolation_mark;
530 }
531 } else if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source,
532 ethhdr->h_dest, vid)) {
533 goto dropped;
534 }
535
536 netif_rx(skb);
537 goto out;
538
539 dropped:
540 kfree_skb(skb);
541 out:
542 return;
543 }
544
545 /**
546 * batadv_meshif_vlan_release() - release vlan from lists and queue for free
547 * after rcu grace period
548 * @ref: kref pointer of the vlan object
549 */
batadv_meshif_vlan_release(struct kref * ref)550 void batadv_meshif_vlan_release(struct kref *ref)
551 {
552 struct batadv_meshif_vlan *vlan;
553
554 vlan = container_of(ref, struct batadv_meshif_vlan, refcount);
555
556 spin_lock_bh(&vlan->bat_priv->meshif_vlan_list_lock);
557 hlist_del_rcu(&vlan->list);
558 spin_unlock_bh(&vlan->bat_priv->meshif_vlan_list_lock);
559
560 kfree_rcu(vlan, rcu);
561 }
562
563 /**
564 * batadv_meshif_vlan_get() - get the vlan object for a specific vid
565 * @bat_priv: the bat priv with all the mesh interface information
566 * @vid: the identifier of the vlan object to retrieve
567 *
568 * Return: the private data of the vlan matching the vid passed as argument or
569 * NULL otherwise. The refcounter of the returned object is incremented by 1.
570 */
batadv_meshif_vlan_get(struct batadv_priv * bat_priv,unsigned short vid)571 struct batadv_meshif_vlan *batadv_meshif_vlan_get(struct batadv_priv *bat_priv,
572 unsigned short vid)
573 {
574 struct batadv_meshif_vlan *vlan = NULL;
575 struct batadv_meshif_vlan *vlan_tmp;
576
577 rcu_read_lock();
578 hlist_for_each_entry_rcu(vlan_tmp, &bat_priv->meshif_vlan_list, list) {
579 if (vlan_tmp->vid != vid)
580 continue;
581
582 if (!kref_get_unless_zero(&vlan_tmp->refcount))
583 continue;
584
585 vlan = vlan_tmp;
586 break;
587 }
588 rcu_read_unlock();
589
590 return vlan;
591 }
592
593 /**
594 * batadv_meshif_create_vlan() - allocate the needed resources for a new vlan
595 * @bat_priv: the bat priv with all the mesh interface information
596 * @vid: the VLAN identifier
597 *
598 * Return: 0 on success, a negative error otherwise.
599 */
batadv_meshif_create_vlan(struct batadv_priv * bat_priv,unsigned short vid)600 int batadv_meshif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
601 {
602 struct batadv_meshif_vlan *vlan;
603
604 spin_lock_bh(&bat_priv->meshif_vlan_list_lock);
605
606 vlan = batadv_meshif_vlan_get(bat_priv, vid);
607 if (vlan) {
608 batadv_meshif_vlan_put(vlan);
609 spin_unlock_bh(&bat_priv->meshif_vlan_list_lock);
610 return -EEXIST;
611 }
612
613 vlan = kzalloc_obj(*vlan, GFP_ATOMIC);
614 if (!vlan) {
615 spin_unlock_bh(&bat_priv->meshif_vlan_list_lock);
616 return -ENOMEM;
617 }
618
619 vlan->bat_priv = bat_priv;
620 vlan->vid = vid;
621 kref_init(&vlan->refcount);
622
623 WRITE_ONCE(vlan->ap_isolation, 0);
624
625 kref_get(&vlan->refcount);
626 hlist_add_head_rcu(&vlan->list, &bat_priv->meshif_vlan_list);
627 spin_unlock_bh(&bat_priv->meshif_vlan_list_lock);
628
629 /* add a new TT local entry. This one will be marked with the NOPURGE
630 * flag
631 */
632 batadv_tt_local_add(bat_priv->mesh_iface,
633 bat_priv->mesh_iface->dev_addr, vid,
634 BATADV_NULL_IFINDEX, BATADV_NO_MARK);
635
636 /* don't return reference to new meshif_vlan */
637 batadv_meshif_vlan_put(vlan);
638
639 return 0;
640 }
641
642 /**
643 * batadv_meshif_destroy_vlan() - remove and destroy a meshif_vlan object
644 * @bat_priv: the bat priv with all the mesh interface information
645 * @vlan: the object to remove
646 */
batadv_meshif_destroy_vlan(struct batadv_priv * bat_priv,struct batadv_meshif_vlan * vlan)647 void batadv_meshif_destroy_vlan(struct batadv_priv *bat_priv,
648 struct batadv_meshif_vlan *vlan)
649 {
650 /* explicitly remove the associated TT local entry because it is marked
651 * with the NOPURGE flag
652 */
653 batadv_tt_local_remove(bat_priv, bat_priv->mesh_iface->dev_addr,
654 vlan->vid, "vlan interface destroyed", false);
655
656 batadv_meshif_vlan_put(vlan);
657 }
658
659 /**
660 * batadv_interface_add_vid() - ndo_add_vid API implementation
661 * @dev: the netdev of the mesh interface
662 * @proto: protocol of the vlan id
663 * @vid: identifier of the new vlan
664 *
665 * Set up all the internal structures for handling the new vlan on top of the
666 * mesh interface
667 *
668 * Return: 0 on success or a negative error code in case of failure.
669 */
batadv_interface_add_vid(struct net_device * dev,__be16 proto,unsigned short vid)670 static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
671 unsigned short vid)
672 {
673 struct batadv_priv *bat_priv = netdev_priv(dev);
674 struct batadv_meshif_vlan *vlan;
675
676 /* only 802.1Q vlans are supported.
677 * batman-adv does not know how to handle other types
678 */
679 if (proto != htons(ETH_P_8021Q))
680 return -EINVAL;
681
682 /* VID 0 is only used to indicate "priority tag" frames which only
683 * contain priority information and no VID. No management structures
684 * should be created for this VID and it should be handled like an
685 * untagged frame.
686 */
687 if (vid == 0)
688 return 0;
689
690 vid |= BATADV_VLAN_HAS_TAG;
691
692 /* if a new vlan is getting created and it already exists, it means that
693 * it was not deleted yet. batadv_meshif_vlan_get() increases the
694 * refcount in order to revive the object.
695 *
696 * if it does not exist then create it.
697 */
698 vlan = batadv_meshif_vlan_get(bat_priv, vid);
699 if (!vlan)
700 return batadv_meshif_create_vlan(bat_priv, vid);
701
702 /* add a new TT local entry. This one will be marked with the NOPURGE
703 * flag. This must be added again, even if the vlan object already
704 * exists, because the entry was deleted by kill_vid()
705 */
706 batadv_tt_local_add(bat_priv->mesh_iface,
707 bat_priv->mesh_iface->dev_addr, vid,
708 BATADV_NULL_IFINDEX, BATADV_NO_MARK);
709
710 return 0;
711 }
712
713 /**
714 * batadv_interface_kill_vid() - ndo_kill_vid API implementation
715 * @dev: the netdev of the mesh interface
716 * @proto: protocol of the vlan id
717 * @vid: identifier of the deleted vlan
718 *
719 * Destroy all the internal structures used to handle the vlan identified by vid
720 * on top of the mesh interface
721 *
722 * Return: 0 on success, -EINVAL if the specified prototype is not ETH_P_8021Q
723 * or -ENOENT if the specified vlan id wasn't registered.
724 */
batadv_interface_kill_vid(struct net_device * dev,__be16 proto,unsigned short vid)725 static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
726 unsigned short vid)
727 {
728 struct batadv_priv *bat_priv = netdev_priv(dev);
729 struct batadv_meshif_vlan *vlan;
730
731 /* only 802.1Q vlans are supported. batman-adv does not know how to
732 * handle other types
733 */
734 if (proto != htons(ETH_P_8021Q))
735 return -EINVAL;
736
737 /* "priority tag" frames are handled like "untagged" frames
738 * and no meshif_vlan needs to be destroyed
739 */
740 if (vid == 0)
741 return 0;
742
743 vlan = batadv_meshif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
744 if (!vlan)
745 return -ENOENT;
746
747 batadv_meshif_destroy_vlan(bat_priv, vlan);
748
749 /* finally free the vlan object */
750 batadv_meshif_vlan_put(vlan);
751
752 return 0;
753 }
754
755 /* batman-adv network devices have devices nesting below it and are a special
756 * "super class" of normal network devices; split their locks off into a
757 * separate class since they always nest.
758 */
759 static struct lock_class_key batadv_netdev_xmit_lock_key;
760 static struct lock_class_key batadv_netdev_addr_lock_key;
761
762 /**
763 * batadv_set_lockdep_class_one() - Set lockdep class for a single tx queue
764 * @dev: device which owns the tx queue
765 * @txq: tx queue to modify
766 * @_unused: always NULL
767 */
batadv_set_lockdep_class_one(struct net_device * dev,struct netdev_queue * txq,void * _unused)768 static void batadv_set_lockdep_class_one(struct net_device *dev,
769 struct netdev_queue *txq,
770 void *_unused)
771 {
772 lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
773 }
774
775 /**
776 * batadv_set_lockdep_class() - Set txq and addr_list lockdep class
777 * @dev: network device to modify
778 */
batadv_set_lockdep_class(struct net_device * dev)779 static void batadv_set_lockdep_class(struct net_device *dev)
780 {
781 lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
782 netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
783 }
784
785 /**
786 * batadv_meshif_init_late() - late stage initialization of mesh interface
787 * @dev: registered network device to modify
788 *
789 * Return: error code on failures
790 */
batadv_meshif_init_late(struct net_device * dev)791 static int batadv_meshif_init_late(struct net_device *dev)
792 {
793 size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
794 struct batadv_priv *bat_priv;
795 u32 random_seqno;
796 int ret;
797
798 batadv_set_lockdep_class(dev);
799
800 bat_priv = netdev_priv(dev);
801 bat_priv->mesh_iface = dev;
802
803 /* batadv_interface_stats() needs to be available as soon as
804 * register_netdevice() has been called
805 */
806 bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(u64));
807 if (!bat_priv->bat_counters)
808 return -ENOMEM;
809
810 WRITE_ONCE(bat_priv->aggregated_ogms, 1);
811 WRITE_ONCE(bat_priv->bonding, 0);
812 #ifdef CONFIG_BATMAN_ADV_BLA
813 WRITE_ONCE(bat_priv->bridge_loop_avoidance, 1);
814 #endif
815 #ifdef CONFIG_BATMAN_ADV_DAT
816 WRITE_ONCE(bat_priv->distributed_arp_table, 1);
817 #endif
818 #ifdef CONFIG_BATMAN_ADV_MCAST
819 WRITE_ONCE(bat_priv->multicast_mode, 1);
820 WRITE_ONCE(bat_priv->multicast_fanout, 16);
821 atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
822 atomic_set(&bat_priv->mcast.num_want_all_ipv4, 0);
823 atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
824 atomic_set(&bat_priv->mcast.num_no_mc_ptype_capa, 0);
825 #endif
826 WRITE_ONCE(bat_priv->gw.mode, BATADV_GW_MODE_OFF);
827 WRITE_ONCE(bat_priv->gw.bandwidth_down, 100);
828 WRITE_ONCE(bat_priv->gw.bandwidth_up, 20);
829 WRITE_ONCE(bat_priv->orig_interval, 1000);
830 WRITE_ONCE(bat_priv->hop_penalty, 30);
831 #ifdef CONFIG_BATMAN_ADV_DEBUG
832 WRITE_ONCE(bat_priv->log_level, 0);
833 #endif
834 WRITE_ONCE(bat_priv->fragmentation, 1);
835 WRITE_ONCE(bat_priv->packet_size_max, BATADV_MAX_MTU);
836 atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
837 atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
838
839 WRITE_ONCE(bat_priv->mesh_state, BATADV_MESH_INACTIVE);
840 atomic_set(&bat_priv->bcast_seqno, 1);
841 atomic_set(&bat_priv->tt.vn, 0);
842 atomic_set(&bat_priv->tt.ogm_append_cnt, 0);
843 #ifdef CONFIG_BATMAN_ADV_BLA
844 atomic_set(&bat_priv->bla.num_requests, 0);
845 spin_lock_init(&bat_priv->bla.num_requests_lock);
846 #endif
847 atomic_set(&bat_priv->tp_num, 0);
848
849 WRITE_ONCE(bat_priv->tt.local_changes, 0);
850 bat_priv->tt.last_changeset = NULL;
851 bat_priv->tt.last_changeset_len = 0;
852 bat_priv->isolation_mark = 0;
853 bat_priv->isolation_mark_mask = 0;
854
855 /* randomize initial seqno to avoid collision */
856 get_random_bytes(&random_seqno, sizeof(random_seqno));
857 atomic_set(&bat_priv->frag_seqno, random_seqno);
858
859 bat_priv->primary_if = NULL;
860
861 if (!bat_priv->algo_ops) {
862 ret = batadv_algo_select(bat_priv, batadv_routing_algo);
863 if (ret < 0)
864 goto free_bat_counters;
865 }
866
867 ret = batadv_mesh_init(dev);
868 if (ret < 0)
869 goto free_bat_counters;
870
871 return 0;
872
873 free_bat_counters:
874 free_percpu(bat_priv->bat_counters);
875 bat_priv->bat_counters = NULL;
876
877 return ret;
878 }
879
880 /**
881 * batadv_meshif_slave_add() - Add a slave interface to a batadv_mesh_interface
882 * @dev: batadv_mesh_interface used as master interface
883 * @slave_dev: net_device which should become the slave interface
884 * @extack: extended ACK report struct
885 *
886 * Return: 0 if successful or error otherwise.
887 */
batadv_meshif_slave_add(struct net_device * dev,struct net_device * slave_dev,struct netlink_ext_ack * extack)888 static int batadv_meshif_slave_add(struct net_device *dev,
889 struct net_device *slave_dev,
890 struct netlink_ext_ack *extack)
891 {
892 return batadv_hardif_enable_interface(slave_dev, dev);
893 }
894
895 /**
896 * batadv_meshif_slave_del() - Delete a slave iface from a batadv_mesh_interface
897 * @dev: batadv_mesh_interface used as master interface
898 * @slave_dev: net_device which should be removed from the master interface
899 *
900 * Return: 0 if successful or error otherwise.
901 */
batadv_meshif_slave_del(struct net_device * dev,struct net_device * slave_dev)902 static int batadv_meshif_slave_del(struct net_device *dev,
903 struct net_device *slave_dev)
904 {
905 struct batadv_hard_iface *hard_iface;
906 int ret = -EINVAL;
907
908 hard_iface = batadv_hardif_get_by_netdev(slave_dev);
909
910 if (!hard_iface || hard_iface->mesh_iface != dev)
911 goto out;
912
913 batadv_hardif_disable_interface(hard_iface);
914 ret = 0;
915
916 out:
917 batadv_hardif_put(hard_iface);
918 return ret;
919 }
920
921 static const struct net_device_ops batadv_netdev_ops = {
922 .ndo_init = batadv_meshif_init_late,
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_meshif_slave_add,
932 .ndo_del_slave = batadv_meshif_slave_del,
933 };
934
935 /**
936 * batadv_get_drvinfo() - ethtool driver info handler for mesh interfaces
937 * @dev: the mesh interface (unused)
938 * @info: ethtool_drvinfo struct to populate
939 */
batadv_get_drvinfo(struct net_device * dev,struct ethtool_drvinfo * info)940 static void batadv_get_drvinfo(struct net_device *dev,
941 struct ethtool_drvinfo *info)
942 {
943 strscpy(info->driver, "B.A.T.M.A.N. advanced", sizeof(info->driver));
944 strscpy(info->version, init_utsname()->release, sizeof(info->version));
945 strscpy(info->fw_version, "N/A", sizeof(info->fw_version));
946 strscpy(info->bus_info, "batman", sizeof(info->bus_info));
947 }
948
949 /* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
950 * Declare each description string in struct.name[] to get fixed sized buffer
951 * and compile time checking for strings longer than ETH_GSTRING_LEN.
952 */
953 static const struct {
954 const char name[ETH_GSTRING_LEN];
955 } batadv_counters_strings[] = {
956 { "tx" },
957 { "tx_bytes" },
958 { "tx_dropped" },
959 { "rx" },
960 { "rx_bytes" },
961 { "forward" },
962 { "forward_bytes" },
963 { "mgmt_tx" },
964 { "mgmt_tx_bytes" },
965 { "mgmt_rx" },
966 { "mgmt_rx_bytes" },
967 { "frag_tx" },
968 { "frag_tx_bytes" },
969 { "frag_rx" },
970 { "frag_rx_bytes" },
971 { "frag_fwd" },
972 { "frag_fwd_bytes" },
973 { "tt_request_tx" },
974 { "tt_request_rx" },
975 { "tt_response_tx" },
976 { "tt_response_rx" },
977 { "tt_roam_adv_tx" },
978 { "tt_roam_adv_rx" },
979 #ifdef CONFIG_BATMAN_ADV_MCAST
980 { "mcast_tx" },
981 { "mcast_tx_bytes" },
982 { "mcast_tx_local" },
983 { "mcast_tx_local_bytes" },
984 { "mcast_rx" },
985 { "mcast_rx_bytes" },
986 { "mcast_rx_local" },
987 { "mcast_rx_local_bytes" },
988 { "mcast_fwd" },
989 { "mcast_fwd_bytes" },
990 #endif
991 #ifdef CONFIG_BATMAN_ADV_DAT
992 { "dat_get_tx" },
993 { "dat_get_rx" },
994 { "dat_put_tx" },
995 { "dat_put_rx" },
996 { "dat_cached_reply_tx" },
997 #endif
998 };
999
1000 /**
1001 * batadv_get_strings() - ethtool string handler for mesh interfaces
1002 * @dev: the mesh interface (unused)
1003 * @stringset: ethtool string set to retrieve
1004 * @data: buffer to copy the requested string set into
1005 */
batadv_get_strings(struct net_device * dev,u32 stringset,u8 * data)1006 static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1007 {
1008 if (stringset == ETH_SS_STATS)
1009 memcpy(data, batadv_counters_strings,
1010 sizeof(batadv_counters_strings));
1011 }
1012
1013 /**
1014 * batadv_get_ethtool_stats() - ethtool stats handler for mesh interfaces
1015 * @dev: the mesh interface to query
1016 * @stats: ethtool_stats struct (unused)
1017 * @data: destination array for the gathered counter values
1018 */
batadv_get_ethtool_stats(struct net_device * dev,struct ethtool_stats * stats,u64 * data)1019 static void batadv_get_ethtool_stats(struct net_device *dev,
1020 struct ethtool_stats *stats, u64 *data)
1021 {
1022 struct batadv_priv *bat_priv = netdev_priv(dev);
1023 int i;
1024
1025 for (i = 0; i < BATADV_CNT_NUM; i++)
1026 data[i] = batadv_sum_counter(bat_priv, i);
1027 }
1028
1029 /**
1030 * batadv_get_sset_count() - ethtool stringset size handler for mesh interfaces
1031 * @dev: the mesh interface (unused)
1032 * @stringset: ethtool string set to query
1033 *
1034 * Return: number of entries in @stringset or -EOPNOTSUPP if @stringset is not
1035 * supported
1036 */
batadv_get_sset_count(struct net_device * dev,int stringset)1037 static int batadv_get_sset_count(struct net_device *dev, int stringset)
1038 {
1039 if (stringset == ETH_SS_STATS)
1040 return BATADV_CNT_NUM;
1041
1042 return -EOPNOTSUPP;
1043 }
1044
1045 static const struct ethtool_ops batadv_ethtool_ops = {
1046 .get_drvinfo = batadv_get_drvinfo,
1047 .get_link = ethtool_op_get_link,
1048 .get_strings = batadv_get_strings,
1049 .get_ethtool_stats = batadv_get_ethtool_stats,
1050 .get_sset_count = batadv_get_sset_count,
1051 };
1052
1053 /**
1054 * batadv_meshif_free() - Deconstructor of batadv_mesh_interface
1055 * @dev: Device to cleanup and remove
1056 */
batadv_meshif_free(struct net_device * dev)1057 static void batadv_meshif_free(struct net_device *dev)
1058 {
1059 batadv_mesh_free(dev);
1060
1061 /* some scheduled RCU callbacks need the bat_priv struct to accomplish
1062 * their tasks. Wait for them all to be finished before freeing the
1063 * netdev and its private data (bat_priv)
1064 */
1065 rcu_barrier();
1066 }
1067
1068 /**
1069 * batadv_meshif_init_early() - early stage initialization of mesh interface
1070 * @dev: registered network device to modify
1071 */
batadv_meshif_init_early(struct net_device * dev)1072 static void batadv_meshif_init_early(struct net_device *dev)
1073 {
1074 ether_setup(dev);
1075
1076 dev->netdev_ops = &batadv_netdev_ops;
1077 dev->needs_free_netdev = true;
1078 dev->priv_destructor = batadv_meshif_free;
1079 dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
1080 dev->priv_flags |= IFF_NO_QUEUE;
1081 dev->lltx = true;
1082 dev->netns_immutable = true;
1083
1084 /* can't call min_mtu, because the needed variables
1085 * have not been initialized yet
1086 */
1087 dev->mtu = ETH_DATA_LEN;
1088 dev->max_mtu = BATADV_MAX_MTU;
1089
1090 /* generate random address */
1091 eth_hw_addr_random(dev);
1092
1093 dev->ethtool_ops = &batadv_ethtool_ops;
1094 }
1095
1096 /**
1097 * batadv_meshif_validate() - validate configuration of new batadv link
1098 * @tb: IFLA_INFO_DATA netlink attributes
1099 * @data: enum batadv_ifla_attrs attributes
1100 * @extack: extended ACK report struct
1101 *
1102 * Return: 0 if successful or error otherwise.
1103 */
batadv_meshif_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1104 static int batadv_meshif_validate(struct nlattr *tb[], struct nlattr *data[],
1105 struct netlink_ext_ack *extack)
1106 {
1107 struct batadv_algo_ops *algo_ops;
1108
1109 if (!data)
1110 return 0;
1111
1112 if (data[IFLA_BATADV_ALGO_NAME]) {
1113 algo_ops = batadv_algo_get(nla_data(data[IFLA_BATADV_ALGO_NAME]));
1114 if (!algo_ops)
1115 return -EINVAL;
1116 }
1117
1118 return 0;
1119 }
1120
1121 /**
1122 * batadv_meshif_newlink() - pre-initialize and register new batadv link
1123 * @dev: network device to register
1124 * @params: rtnl newlink parameters
1125 * @extack: extended ACK report struct
1126 *
1127 * Return: 0 if successful or error otherwise.
1128 */
batadv_meshif_newlink(struct net_device * dev,struct rtnl_newlink_params * params,struct netlink_ext_ack * extack)1129 static int batadv_meshif_newlink(struct net_device *dev,
1130 struct rtnl_newlink_params *params,
1131 struct netlink_ext_ack *extack)
1132 {
1133 struct batadv_priv *bat_priv = netdev_priv(dev);
1134 struct nlattr **data = params->data;
1135 const char *algo_name;
1136 int err;
1137
1138 if (data && data[IFLA_BATADV_ALGO_NAME]) {
1139 algo_name = nla_data(data[IFLA_BATADV_ALGO_NAME]);
1140 err = batadv_algo_select(bat_priv, algo_name);
1141 if (err)
1142 return -EINVAL;
1143 }
1144
1145 return register_netdevice(dev);
1146 }
1147
1148 /**
1149 * batadv_meshif_destroy_netlink() - deletion of batadv_mesh_interface via
1150 * netlink
1151 * @mesh_iface: the to-be-removed batman-adv interface
1152 * @head: list pointer
1153 */
batadv_meshif_destroy_netlink(struct net_device * mesh_iface,struct list_head * head)1154 static void batadv_meshif_destroy_netlink(struct net_device *mesh_iface,
1155 struct list_head *head)
1156 {
1157 struct batadv_hard_iface *hard_iface;
1158
1159 while (!list_empty(&mesh_iface->adj_list.lower)) {
1160 hard_iface = netdev_adjacent_get_private(mesh_iface->adj_list.lower.next);
1161 batadv_hardif_disable_interface(hard_iface);
1162 }
1163
1164 unregister_netdevice_queue(mesh_iface, head);
1165 }
1166
1167 /**
1168 * batadv_meshif_is_valid() - Check whether device is a batadv mesh interface
1169 * @net_dev: device which should be checked
1170 *
1171 * Return: true when net_dev is a batman-adv interface, false otherwise
1172 */
batadv_meshif_is_valid(const struct net_device * net_dev)1173 bool batadv_meshif_is_valid(const struct net_device *net_dev)
1174 {
1175 if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
1176 return true;
1177
1178 return false;
1179 }
1180
1181 static const struct nla_policy batadv_ifla_policy[IFLA_BATADV_MAX + 1] = {
1182 [IFLA_BATADV_ALGO_NAME] = { .type = NLA_NUL_STRING },
1183 };
1184
1185 struct rtnl_link_ops batadv_link_ops __read_mostly = {
1186 .kind = "batadv",
1187 .priv_size = sizeof(struct batadv_priv),
1188 .setup = batadv_meshif_init_early,
1189 .maxtype = IFLA_BATADV_MAX,
1190 .policy = batadv_ifla_policy,
1191 .validate = batadv_meshif_validate,
1192 .newlink = batadv_meshif_newlink,
1193 .dellink = batadv_meshif_destroy_netlink,
1194 };
1195