1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2007-2020 B.A.T.M.A.N. contributors:
4 * Marek Lindner, Simon Wunderlich
9 #include <linux/byteorder/generic.h>
10 #include <linux/etherdevice.h>
11 #include <linux/gfp.h>
12 #include <linux/if_ether.h>
13 #include <linux/kernel.h>
14 #include <linux/kref.h>
15 #include <linux/list.h>
16 #include <linux/lockdep.h>
17 #include <linux/netdevice.h>
18 #include <linux/pkt_sched.h>
19 #include <linux/rculist.h>
20 #include <linux/rcupdate.h>
21 #include <linux/skbuff.h>
22 #include <linux/slab.h>
23 #include <linux/spinlock.h>
24 #include <linux/stddef.h>
25 #include <linux/string.h>
26 #include <linux/types.h>
27 #include <uapi/linux/batadv_packet.h>
29 #include "originator.h"
34 * batadv_tvlv_handler_release() - release tvlv handler from lists and queue for
35 * free after rcu grace period
36 * @ref: kref pointer of the tvlv
38 static void batadv_tvlv_handler_release(struct kref *ref)
40 struct batadv_tvlv_handler *tvlv_handler;
42 tvlv_handler = container_of(ref, struct batadv_tvlv_handler, refcount);
43 kfree_rcu(tvlv_handler, rcu);
47 * batadv_tvlv_handler_put() - decrement the tvlv container refcounter and
49 * @tvlv_handler: the tvlv handler to free
51 static void batadv_tvlv_handler_put(struct batadv_tvlv_handler *tvlv_handler)
56 kref_put(&tvlv_handler->refcount, batadv_tvlv_handler_release);
60 * batadv_tvlv_handler_get() - retrieve tvlv handler from the tvlv handler list
61 * based on the provided type and version (both need to match)
62 * @bat_priv: the bat priv with all the soft interface information
63 * @type: tvlv handler type to look for
64 * @version: tvlv handler version to look for
66 * Return: tvlv handler if found or NULL otherwise.
68 static struct batadv_tvlv_handler *
69 batadv_tvlv_handler_get(struct batadv_priv *bat_priv, u8 type, u8 version)
71 struct batadv_tvlv_handler *tvlv_handler_tmp, *tvlv_handler = NULL;
74 hlist_for_each_entry_rcu(tvlv_handler_tmp,
75 &bat_priv->tvlv.handler_list, list) {
76 if (tvlv_handler_tmp->type != type)
79 if (tvlv_handler_tmp->version != version)
82 if (!kref_get_unless_zero(&tvlv_handler_tmp->refcount))
85 tvlv_handler = tvlv_handler_tmp;
94 * batadv_tvlv_container_release() - release tvlv from lists and free
95 * @ref: kref pointer of the tvlv
97 static void batadv_tvlv_container_release(struct kref *ref)
99 struct batadv_tvlv_container *tvlv;
101 tvlv = container_of(ref, struct batadv_tvlv_container, refcount);
106 * batadv_tvlv_container_put() - decrement the tvlv container refcounter and
107 * possibly release it
108 * @tvlv: the tvlv container to free
110 static void batadv_tvlv_container_put(struct batadv_tvlv_container *tvlv)
115 kref_put(&tvlv->refcount, batadv_tvlv_container_release);
119 * batadv_tvlv_container_get() - retrieve tvlv container from the tvlv container
120 * list based on the provided type and version (both need to match)
121 * @bat_priv: the bat priv with all the soft interface information
122 * @type: tvlv container type to look for
123 * @version: tvlv container version to look for
125 * Has to be called with the appropriate locks being acquired
126 * (tvlv.container_list_lock).
128 * Return: tvlv container if found or NULL otherwise.
130 static struct batadv_tvlv_container *
131 batadv_tvlv_container_get(struct batadv_priv *bat_priv, u8 type, u8 version)
133 struct batadv_tvlv_container *tvlv_tmp, *tvlv = NULL;
135 lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
137 hlist_for_each_entry(tvlv_tmp, &bat_priv->tvlv.container_list, list) {
138 if (tvlv_tmp->tvlv_hdr.type != type)
141 if (tvlv_tmp->tvlv_hdr.version != version)
144 kref_get(&tvlv_tmp->refcount);
153 * batadv_tvlv_container_list_size() - calculate the size of the tvlv container
155 * @bat_priv: the bat priv with all the soft interface information
157 * Has to be called with the appropriate locks being acquired
158 * (tvlv.container_list_lock).
160 * Return: size of all currently registered tvlv containers in bytes.
162 static u16 batadv_tvlv_container_list_size(struct batadv_priv *bat_priv)
164 struct batadv_tvlv_container *tvlv;
167 lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
169 hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
170 tvlv_len += sizeof(struct batadv_tvlv_hdr);
171 tvlv_len += ntohs(tvlv->tvlv_hdr.len);
178 * batadv_tvlv_container_remove() - remove tvlv container from the tvlv
180 * @bat_priv: the bat priv with all the soft interface information
181 * @tvlv: the to be removed tvlv container
183 * Has to be called with the appropriate locks being acquired
184 * (tvlv.container_list_lock).
186 static void batadv_tvlv_container_remove(struct batadv_priv *bat_priv,
187 struct batadv_tvlv_container *tvlv)
189 lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
194 hlist_del(&tvlv->list);
196 /* first call to decrement the counter, second call to free */
197 batadv_tvlv_container_put(tvlv);
198 batadv_tvlv_container_put(tvlv);
202 * batadv_tvlv_container_unregister() - unregister tvlv container based on the
203 * provided type and version (both need to match)
204 * @bat_priv: the bat priv with all the soft interface information
205 * @type: tvlv container type to unregister
206 * @version: tvlv container type to unregister
208 void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
211 struct batadv_tvlv_container *tvlv;
213 spin_lock_bh(&bat_priv->tvlv.container_list_lock);
214 tvlv = batadv_tvlv_container_get(bat_priv, type, version);
215 batadv_tvlv_container_remove(bat_priv, tvlv);
216 spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
220 * batadv_tvlv_container_register() - register tvlv type, version and content
221 * to be propagated with each (primary interface) OGM
222 * @bat_priv: the bat priv with all the soft interface information
223 * @type: tvlv container type
224 * @version: tvlv container version
225 * @tvlv_value: tvlv container content
226 * @tvlv_value_len: tvlv container content length
228 * If a container of the same type and version was already registered the new
229 * content is going to replace the old one.
231 void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
233 void *tvlv_value, u16 tvlv_value_len)
235 struct batadv_tvlv_container *tvlv_old, *tvlv_new;
240 tvlv_new = kzalloc(sizeof(*tvlv_new) + tvlv_value_len, GFP_ATOMIC);
244 tvlv_new->tvlv_hdr.version = version;
245 tvlv_new->tvlv_hdr.type = type;
246 tvlv_new->tvlv_hdr.len = htons(tvlv_value_len);
248 memcpy(tvlv_new + 1, tvlv_value, ntohs(tvlv_new->tvlv_hdr.len));
249 INIT_HLIST_NODE(&tvlv_new->list);
250 kref_init(&tvlv_new->refcount);
252 spin_lock_bh(&bat_priv->tvlv.container_list_lock);
253 tvlv_old = batadv_tvlv_container_get(bat_priv, type, version);
254 batadv_tvlv_container_remove(bat_priv, tvlv_old);
256 kref_get(&tvlv_new->refcount);
257 hlist_add_head(&tvlv_new->list, &bat_priv->tvlv.container_list);
258 spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
260 /* don't return reference to new tvlv_container */
261 batadv_tvlv_container_put(tvlv_new);
265 * batadv_tvlv_realloc_packet_buff() - reallocate packet buffer to accommodate
266 * requested packet size
267 * @packet_buff: packet buffer
268 * @packet_buff_len: packet buffer size
269 * @min_packet_len: requested packet minimum size
270 * @additional_packet_len: requested additional packet size on top of minimum
273 * Return: true of the packet buffer could be changed to the requested size,
276 static bool batadv_tvlv_realloc_packet_buff(unsigned char **packet_buff,
277 int *packet_buff_len,
279 int additional_packet_len)
281 unsigned char *new_buff;
283 new_buff = kmalloc(min_packet_len + additional_packet_len, GFP_ATOMIC);
285 /* keep old buffer if kmalloc should fail */
289 memcpy(new_buff, *packet_buff, min_packet_len);
291 *packet_buff = new_buff;
292 *packet_buff_len = min_packet_len + additional_packet_len;
298 * batadv_tvlv_container_ogm_append() - append tvlv container content to given
300 * @bat_priv: the bat priv with all the soft interface information
301 * @packet_buff: ogm packet buffer
302 * @packet_buff_len: ogm packet buffer size including ogm header and tvlv
304 * @packet_min_len: ogm header size to be preserved for the OGM itself
306 * The ogm packet might be enlarged or shrunk depending on the current size
307 * and the size of the to-be-appended tvlv containers.
309 * Return: size of all appended tvlv containers in bytes.
311 u16 batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
312 unsigned char **packet_buff,
313 int *packet_buff_len, int packet_min_len)
315 struct batadv_tvlv_container *tvlv;
316 struct batadv_tvlv_hdr *tvlv_hdr;
321 spin_lock_bh(&bat_priv->tvlv.container_list_lock);
322 tvlv_value_len = batadv_tvlv_container_list_size(bat_priv);
324 ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len,
325 packet_min_len, tvlv_value_len);
333 tvlv_value = (*packet_buff) + packet_min_len;
335 hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
336 tvlv_hdr = tvlv_value;
337 tvlv_hdr->type = tvlv->tvlv_hdr.type;
338 tvlv_hdr->version = tvlv->tvlv_hdr.version;
339 tvlv_hdr->len = tvlv->tvlv_hdr.len;
340 tvlv_value = tvlv_hdr + 1;
341 memcpy(tvlv_value, tvlv + 1, ntohs(tvlv->tvlv_hdr.len));
342 tvlv_value = (u8 *)tvlv_value + ntohs(tvlv->tvlv_hdr.len);
346 spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
347 return tvlv_value_len;
351 * batadv_tvlv_call_handler() - parse the given tvlv buffer to call the
352 * appropriate handlers
353 * @bat_priv: the bat priv with all the soft interface information
354 * @tvlv_handler: tvlv callback function handling the tvlv content
355 * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
356 * @orig_node: orig node emitting the ogm packet
357 * @src: source mac address of the unicast packet
358 * @dst: destination mac address of the unicast packet
359 * @tvlv_value: tvlv content
360 * @tvlv_value_len: tvlv content length
362 * Return: success if the handler was not found or the return value of the
365 static int batadv_tvlv_call_handler(struct batadv_priv *bat_priv,
366 struct batadv_tvlv_handler *tvlv_handler,
368 struct batadv_orig_node *orig_node,
370 void *tvlv_value, u16 tvlv_value_len)
373 return NET_RX_SUCCESS;
376 if (!tvlv_handler->ogm_handler)
377 return NET_RX_SUCCESS;
380 return NET_RX_SUCCESS;
382 tvlv_handler->ogm_handler(bat_priv, orig_node,
384 tvlv_value, tvlv_value_len);
385 tvlv_handler->flags |= BATADV_TVLV_HANDLER_OGM_CALLED;
388 return NET_RX_SUCCESS;
391 return NET_RX_SUCCESS;
393 if (!tvlv_handler->unicast_handler)
394 return NET_RX_SUCCESS;
396 return tvlv_handler->unicast_handler(bat_priv, src,
401 return NET_RX_SUCCESS;
405 * batadv_tvlv_containers_process() - parse the given tvlv buffer to call the
406 * appropriate handlers
407 * @bat_priv: the bat priv with all the soft interface information
408 * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
409 * @orig_node: orig node emitting the ogm packet
410 * @src: source mac address of the unicast packet
411 * @dst: destination mac address of the unicast packet
412 * @tvlv_value: tvlv content
413 * @tvlv_value_len: tvlv content length
415 * Return: success when processing an OGM or the return value of all called
418 int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
420 struct batadv_orig_node *orig_node,
422 void *tvlv_value, u16 tvlv_value_len)
424 struct batadv_tvlv_handler *tvlv_handler;
425 struct batadv_tvlv_hdr *tvlv_hdr;
426 u16 tvlv_value_cont_len;
427 u8 cifnotfound = BATADV_TVLV_HANDLER_OGM_CIFNOTFND;
428 int ret = NET_RX_SUCCESS;
430 while (tvlv_value_len >= sizeof(*tvlv_hdr)) {
431 tvlv_hdr = tvlv_value;
432 tvlv_value_cont_len = ntohs(tvlv_hdr->len);
433 tvlv_value = tvlv_hdr + 1;
434 tvlv_value_len -= sizeof(*tvlv_hdr);
436 if (tvlv_value_cont_len > tvlv_value_len)
439 tvlv_handler = batadv_tvlv_handler_get(bat_priv,
443 ret |= batadv_tvlv_call_handler(bat_priv, tvlv_handler,
444 ogm_source, orig_node,
445 src, dst, tvlv_value,
446 tvlv_value_cont_len);
448 batadv_tvlv_handler_put(tvlv_handler);
449 tvlv_value = (u8 *)tvlv_value + tvlv_value_cont_len;
450 tvlv_value_len -= tvlv_value_cont_len;
457 hlist_for_each_entry_rcu(tvlv_handler,
458 &bat_priv->tvlv.handler_list, list) {
459 if ((tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) &&
460 !(tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CALLED))
461 tvlv_handler->ogm_handler(bat_priv, orig_node,
462 cifnotfound, NULL, 0);
464 tvlv_handler->flags &= ~BATADV_TVLV_HANDLER_OGM_CALLED;
468 return NET_RX_SUCCESS;
472 * batadv_tvlv_ogm_receive() - process an incoming ogm and call the appropriate
474 * @bat_priv: the bat priv with all the soft interface information
475 * @batadv_ogm_packet: ogm packet containing the tvlv containers
476 * @orig_node: orig node emitting the ogm packet
478 void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
479 struct batadv_ogm_packet *batadv_ogm_packet,
480 struct batadv_orig_node *orig_node)
485 if (!batadv_ogm_packet)
488 tvlv_value_len = ntohs(batadv_ogm_packet->tvlv_len);
492 tvlv_value = batadv_ogm_packet + 1;
494 batadv_tvlv_containers_process(bat_priv, true, orig_node, NULL, NULL,
495 tvlv_value, tvlv_value_len);
499 * batadv_tvlv_handler_register() - register tvlv handler based on the provided
500 * type and version (both need to match) for ogm tvlv payload and/or unicast
502 * @bat_priv: the bat priv with all the soft interface information
503 * @optr: ogm tvlv handler callback function. This function receives the orig
504 * node, flags and the tvlv content as argument to process.
505 * @uptr: unicast tvlv handler callback function. This function receives the
506 * source & destination of the unicast packet as well as the tvlv content
508 * @type: tvlv handler type to be registered
509 * @version: tvlv handler version to be registered
510 * @flags: flags to enable or disable TVLV API behavior
512 void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
513 void (*optr)(struct batadv_priv *bat_priv,
514 struct batadv_orig_node *orig,
518 int (*uptr)(struct batadv_priv *bat_priv,
522 u8 type, u8 version, u8 flags)
524 struct batadv_tvlv_handler *tvlv_handler;
526 spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
528 tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
530 spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
531 batadv_tvlv_handler_put(tvlv_handler);
535 tvlv_handler = kzalloc(sizeof(*tvlv_handler), GFP_ATOMIC);
537 spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
541 tvlv_handler->ogm_handler = optr;
542 tvlv_handler->unicast_handler = uptr;
543 tvlv_handler->type = type;
544 tvlv_handler->version = version;
545 tvlv_handler->flags = flags;
546 kref_init(&tvlv_handler->refcount);
547 INIT_HLIST_NODE(&tvlv_handler->list);
549 kref_get(&tvlv_handler->refcount);
550 hlist_add_head_rcu(&tvlv_handler->list, &bat_priv->tvlv.handler_list);
551 spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
553 /* don't return reference to new tvlv_handler */
554 batadv_tvlv_handler_put(tvlv_handler);
558 * batadv_tvlv_handler_unregister() - unregister tvlv handler based on the
559 * provided type and version (both need to match)
560 * @bat_priv: the bat priv with all the soft interface information
561 * @type: tvlv handler type to be unregistered
562 * @version: tvlv handler version to be unregistered
564 void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
567 struct batadv_tvlv_handler *tvlv_handler;
569 tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
573 batadv_tvlv_handler_put(tvlv_handler);
574 spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
575 hlist_del_rcu(&tvlv_handler->list);
576 spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
577 batadv_tvlv_handler_put(tvlv_handler);
581 * batadv_tvlv_unicast_send() - send a unicast packet with tvlv payload to the
583 * @bat_priv: the bat priv with all the soft interface information
584 * @src: source mac address of the unicast packet
585 * @dst: destination mac address of the unicast packet
587 * @version: tvlv version
588 * @tvlv_value: tvlv content
589 * @tvlv_value_len: tvlv content length
591 void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, u8 *src,
592 u8 *dst, u8 type, u8 version,
593 void *tvlv_value, u16 tvlv_value_len)
595 struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
596 struct batadv_tvlv_hdr *tvlv_hdr;
597 struct batadv_orig_node *orig_node;
599 unsigned char *tvlv_buff;
600 unsigned int tvlv_len;
601 ssize_t hdr_len = sizeof(*unicast_tvlv_packet);
603 orig_node = batadv_orig_hash_find(bat_priv, dst);
607 tvlv_len = sizeof(*tvlv_hdr) + tvlv_value_len;
609 skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + hdr_len + tvlv_len);
613 skb->priority = TC_PRIO_CONTROL;
614 skb_reserve(skb, ETH_HLEN);
615 tvlv_buff = skb_put(skb, sizeof(*unicast_tvlv_packet) + tvlv_len);
616 unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)tvlv_buff;
617 unicast_tvlv_packet->packet_type = BATADV_UNICAST_TVLV;
618 unicast_tvlv_packet->version = BATADV_COMPAT_VERSION;
619 unicast_tvlv_packet->ttl = BATADV_TTL;
620 unicast_tvlv_packet->reserved = 0;
621 unicast_tvlv_packet->tvlv_len = htons(tvlv_len);
622 unicast_tvlv_packet->align = 0;
623 ether_addr_copy(unicast_tvlv_packet->src, src);
624 ether_addr_copy(unicast_tvlv_packet->dst, dst);
626 tvlv_buff = (unsigned char *)(unicast_tvlv_packet + 1);
627 tvlv_hdr = (struct batadv_tvlv_hdr *)tvlv_buff;
628 tvlv_hdr->version = version;
629 tvlv_hdr->type = type;
630 tvlv_hdr->len = htons(tvlv_value_len);
631 tvlv_buff += sizeof(*tvlv_hdr);
632 memcpy(tvlv_buff, tvlv_value, tvlv_value_len);
634 batadv_send_skb_to_orig(skb, orig_node, NULL);
636 batadv_orig_node_put(orig_node);