blob: e96d7c745b4a1de6444284f38207ed599925ac2e [file] [log] [blame]
Sven Eckelmann0046b042016-01-01 00:01:03 +01001/* Copyright (C) 2011-2016 B.A.T.M.A.N. contributors:
Antonio Quartulli785ea112011-11-23 11:35:44 +01002 *
3 * Antonio Quartulli
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
Antonio Quartulliebf38fb2013-11-03 20:40:48 +010015 * along with this program; if not, see <http://www.gnu.org/licenses/>.
Antonio Quartulli785ea112011-11-23 11:35:44 +010016 */
17
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020018#include "distributed-arp-table.h"
19#include "main.h"
20
21#include <linux/atomic.h>
Linus Lüssing65d7d4602015-06-16 17:10:22 +020022#include <linux/bitops.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020023#include <linux/byteorder/generic.h>
24#include <linux/errno.h>
25#include <linux/etherdevice.h>
26#include <linux/fs.h>
Antonio Quartulli785ea112011-11-23 11:35:44 +010027#include <linux/if_arp.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020028#include <linux/if_ether.h>
Antonio Quartullibe1db4f2013-06-04 12:11:43 +020029#include <linux/if_vlan.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020030#include <linux/in.h>
31#include <linux/jiffies.h>
32#include <linux/kernel.h>
Sven Eckelmann68a67222016-01-16 10:29:47 +010033#include <linux/kref.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020034#include <linux/list.h>
35#include <linux/rculist.h>
36#include <linux/rcupdate.h>
37#include <linux/seq_file.h>
38#include <linux/skbuff.h>
39#include <linux/slab.h>
40#include <linux/spinlock.h>
41#include <linux/stddef.h>
42#include <linux/string.h>
43#include <linux/workqueue.h>
Antonio Quartullic384ea32011-06-26 03:37:18 +020044#include <net/arp.h>
Antonio Quartulli785ea112011-11-23 11:35:44 +010045
Antonio Quartulli785ea112011-11-23 11:35:44 +010046#include "hard-interface.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020047#include "hash.h"
Antonio Quartulli785ea112011-11-23 11:35:44 +010048#include "originator.h"
49#include "send.h"
Antonio Quartullic384ea32011-06-26 03:37:18 +020050#include "translation-table.h"
Antonio Quartulli785ea112011-11-23 11:35:44 +010051
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020052static void batadv_dat_purge(struct work_struct *work);
53
54/**
55 * batadv_dat_start_timer - initialise the DAT periodic worker
56 * @bat_priv: the bat priv with all the soft interface information
57 */
58static void batadv_dat_start_timer(struct batadv_priv *bat_priv)
59{
60 INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge);
61 queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work,
62 msecs_to_jiffies(10000));
63}
64
65/**
Sven Eckelmann68a67222016-01-16 10:29:47 +010066 * batadv_dat_entry_release - release dat_entry from lists and queue for free
67 * after rcu grace period
68 * @ref: kref pointer of the dat_entry
69 */
70static void batadv_dat_entry_release(struct kref *ref)
71{
72 struct batadv_dat_entry *dat_entry;
73
74 dat_entry = container_of(ref, struct batadv_dat_entry, refcount);
75
76 kfree_rcu(dat_entry, rcu);
77}
78
79/**
Sven Eckelmanna6416f92016-01-17 11:01:17 +010080 * batadv_dat_entry_put - decrement the dat_entry refcounter and possibly
Sven Eckelmann68a67222016-01-16 10:29:47 +010081 * release it
82 * @dat_entry: dat_entry to be free'd
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020083 */
Sven Eckelmanna6416f92016-01-17 11:01:17 +010084static void batadv_dat_entry_put(struct batadv_dat_entry *dat_entry)
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020085{
Sven Eckelmann68a67222016-01-16 10:29:47 +010086 kref_put(&dat_entry->refcount, batadv_dat_entry_release);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020087}
88
89/**
Marek Lindner93178012013-03-10 19:29:15 +080090 * batadv_dat_to_purge - check whether a dat_entry has to be purged or not
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020091 * @dat_entry: the entry to check
92 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +020093 * Return: true if the entry has to be purged now, false otherwise.
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +020094 */
95static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry)
96{
97 return batadv_has_timed_out(dat_entry->last_update,
98 BATADV_DAT_ENTRY_TIMEOUT);
99}
100
101/**
102 * __batadv_dat_purge - delete entries from the DAT local storage
103 * @bat_priv: the bat priv with all the soft interface information
104 * @to_purge: function in charge to decide whether an entry has to be purged or
105 * not. This function takes the dat_entry as argument and has to
106 * returns a boolean value: true is the entry has to be deleted,
107 * false otherwise
108 *
Marek Lindner93178012013-03-10 19:29:15 +0800109 * Loops over each entry in the DAT local storage and deletes it if and only if
110 * the to_purge function passed as argument returns true.
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200111 */
112static void __batadv_dat_purge(struct batadv_priv *bat_priv,
113 bool (*to_purge)(struct batadv_dat_entry *))
114{
115 spinlock_t *list_lock; /* protects write access to the hash lists */
116 struct batadv_dat_entry *dat_entry;
Sasha Levinb67bfe02013-02-27 17:06:00 -0800117 struct hlist_node *node_tmp;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200118 struct hlist_head *head;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200119 u32 i;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200120
121 if (!bat_priv->dat.hash)
122 return;
123
124 for (i = 0; i < bat_priv->dat.hash->size; i++) {
125 head = &bat_priv->dat.hash->table[i];
126 list_lock = &bat_priv->dat.hash->list_locks[i];
127
128 spin_lock_bh(list_lock);
Sasha Levinb67bfe02013-02-27 17:06:00 -0800129 hlist_for_each_entry_safe(dat_entry, node_tmp, head,
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200130 hash_entry) {
Marek Lindner93178012013-03-10 19:29:15 +0800131 /* if a helper function has been passed as parameter,
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200132 * ask it if the entry has to be purged or not
133 */
134 if (to_purge && !to_purge(dat_entry))
135 continue;
136
Sasha Levinb67bfe02013-02-27 17:06:00 -0800137 hlist_del_rcu(&dat_entry->hash_entry);
Sven Eckelmanna6416f92016-01-17 11:01:17 +0100138 batadv_dat_entry_put(dat_entry);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200139 }
140 spin_unlock_bh(list_lock);
141 }
142}
143
144/**
145 * batadv_dat_purge - periodic task that deletes old entries from the local DAT
146 * hash table
147 * @work: kernel work struct
148 */
149static void batadv_dat_purge(struct work_struct *work)
150{
151 struct delayed_work *delayed_work;
152 struct batadv_priv_dat *priv_dat;
153 struct batadv_priv *bat_priv;
154
155 delayed_work = container_of(work, struct delayed_work, work);
156 priv_dat = container_of(delayed_work, struct batadv_priv_dat, work);
157 bat_priv = container_of(priv_dat, struct batadv_priv, dat);
158
159 __batadv_dat_purge(bat_priv, batadv_dat_to_purge);
160 batadv_dat_start_timer(bat_priv);
161}
162
163/**
164 * batadv_compare_dat - comparing function used in the local DAT hash table
165 * @node: node in the local table
166 * @data2: second object to compare the node to
167 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200168 * Return: 1 if the two entries are the same, 0 otherwise.
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200169 */
170static int batadv_compare_dat(const struct hlist_node *node, const void *data2)
171{
172 const void *data1 = container_of(node, struct batadv_dat_entry,
173 hash_entry);
174
Antonio Quartulli36484f82013-11-07 08:02:07 +0100175 return memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200176}
177
Antonio Quartulli785ea112011-11-23 11:35:44 +0100178/**
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200179 * batadv_arp_hw_src - extract the hw_src field from an ARP packet
180 * @skb: ARP packet
181 * @hdr_size: size of the possible header before the ARP packet
182 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200183 * Return: the value of the hw_src field in the ARP packet.
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200184 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200185static u8 *batadv_arp_hw_src(struct sk_buff *skb, int hdr_size)
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200186{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200187 u8 *addr;
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200188
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200189 addr = (u8 *)(skb->data + hdr_size);
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200190 addr += ETH_HLEN + sizeof(struct arphdr);
191
192 return addr;
193}
194
195/**
196 * batadv_arp_ip_src - extract the ip_src field from an ARP packet
197 * @skb: ARP packet
198 * @hdr_size: size of the possible header before the ARP packet
199 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200200 * Return: the value of the ip_src field in the ARP packet.
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200201 */
202static __be32 batadv_arp_ip_src(struct sk_buff *skb, int hdr_size)
203{
204 return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN);
205}
206
207/**
208 * batadv_arp_hw_dst - extract the hw_dst field from an ARP packet
209 * @skb: ARP packet
210 * @hdr_size: size of the possible header before the ARP packet
211 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200212 * Return: the value of the hw_dst field in the ARP packet.
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200213 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200214static u8 *batadv_arp_hw_dst(struct sk_buff *skb, int hdr_size)
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200215{
216 return batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN + 4;
217}
218
219/**
220 * batadv_arp_ip_dst - extract the ip_dst field from an ARP packet
221 * @skb: ARP packet
222 * @hdr_size: size of the possible header before the ARP packet
223 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200224 * Return: the value of the ip_dst field in the ARP packet.
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200225 */
226static __be32 batadv_arp_ip_dst(struct sk_buff *skb, int hdr_size)
227{
228 return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN * 2 + 4);
229}
230
231/**
Antonio Quartulli785ea112011-11-23 11:35:44 +0100232 * batadv_hash_dat - compute the hash value for an IP address
233 * @data: data to hash
234 * @size: size of the hash table
235 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200236 * Return: the selected index in the hash table for the given data.
Antonio Quartulli785ea112011-11-23 11:35:44 +0100237 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200238static u32 batadv_hash_dat(const void *data, u32 size)
Antonio Quartulli785ea112011-11-23 11:35:44 +0100239{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200240 u32 hash = 0;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200241 const struct batadv_dat_entry *dat = data;
Sven Eckelmann36fd61c2015-03-01 09:46:18 +0100242 const unsigned char *key;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200243 u32 i;
Antonio Quartulli785ea112011-11-23 11:35:44 +0100244
Sven Eckelmann36fd61c2015-03-01 09:46:18 +0100245 key = (const unsigned char *)&dat->ip;
246 for (i = 0; i < sizeof(dat->ip); i++) {
247 hash += key[i];
248 hash += (hash << 10);
249 hash ^= (hash >> 6);
250 }
251
252 key = (const unsigned char *)&dat->vid;
253 for (i = 0; i < sizeof(dat->vid); i++) {
254 hash += key[i];
255 hash += (hash << 10);
256 hash ^= (hash >> 6);
257 }
Antonio Quartulli785ea112011-11-23 11:35:44 +0100258
259 hash += (hash << 3);
260 hash ^= (hash >> 11);
261 hash += (hash << 15);
262
263 return hash % size;
264}
265
266/**
Marek Lindner93178012013-03-10 19:29:15 +0800267 * batadv_dat_entry_hash_find - look for a given dat_entry in the local hash
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200268 * table
269 * @bat_priv: the bat priv with all the soft interface information
270 * @ip: search key
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200271 * @vid: VLAN identifier
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200272 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200273 * Return: the dat_entry if found, NULL otherwise.
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200274 */
275static struct batadv_dat_entry *
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200276batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip,
277 unsigned short vid)
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200278{
279 struct hlist_head *head;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200280 struct batadv_dat_entry to_find, *dat_entry, *dat_entry_tmp = NULL;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200281 struct batadv_hashtable *hash = bat_priv->dat.hash;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200282 u32 index;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200283
284 if (!hash)
285 return NULL;
286
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200287 to_find.ip = ip;
288 to_find.vid = vid;
289
290 index = batadv_hash_dat(&to_find, hash->size);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200291 head = &hash->table[index];
292
293 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800294 hlist_for_each_entry_rcu(dat_entry, head, hash_entry) {
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200295 if (dat_entry->ip != ip)
296 continue;
297
Sven Eckelmann68a67222016-01-16 10:29:47 +0100298 if (!kref_get_unless_zero(&dat_entry->refcount))
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200299 continue;
300
301 dat_entry_tmp = dat_entry;
302 break;
303 }
304 rcu_read_unlock();
305
306 return dat_entry_tmp;
307}
308
309/**
310 * batadv_dat_entry_add - add a new dat entry or update it if already exists
311 * @bat_priv: the bat priv with all the soft interface information
312 * @ip: ipv4 to add/edit
313 * @mac_addr: mac address to assign to the given ipv4
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200314 * @vid: VLAN identifier
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200315 */
316static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200317 u8 *mac_addr, unsigned short vid)
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200318{
319 struct batadv_dat_entry *dat_entry;
320 int hash_added;
321
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200322 dat_entry = batadv_dat_entry_hash_find(bat_priv, ip, vid);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200323 /* if this entry is already known, just update it */
324 if (dat_entry) {
325 if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr))
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100326 ether_addr_copy(dat_entry->mac_addr, mac_addr);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200327 dat_entry->last_update = jiffies;
328 batadv_dbg(BATADV_DBG_DAT, bat_priv,
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200329 "Entry updated: %pI4 %pM (vid: %d)\n",
330 &dat_entry->ip, dat_entry->mac_addr,
331 BATADV_PRINT_VID(vid));
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200332 goto out;
333 }
334
335 dat_entry = kmalloc(sizeof(*dat_entry), GFP_ATOMIC);
336 if (!dat_entry)
337 goto out;
338
339 dat_entry->ip = ip;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200340 dat_entry->vid = vid;
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100341 ether_addr_copy(dat_entry->mac_addr, mac_addr);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200342 dat_entry->last_update = jiffies;
Sven Eckelmann68a67222016-01-16 10:29:47 +0100343 kref_init(&dat_entry->refcount);
344 kref_get(&dat_entry->refcount);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200345
346 hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat,
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200347 batadv_hash_dat, dat_entry,
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200348 &dat_entry->hash_entry);
349
350 if (unlikely(hash_added != 0)) {
351 /* remove the reference for the hash */
Sven Eckelmanna6416f92016-01-17 11:01:17 +0100352 batadv_dat_entry_put(dat_entry);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200353 goto out;
354 }
355
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200356 batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM (vid: %d)\n",
357 &dat_entry->ip, dat_entry->mac_addr, BATADV_PRINT_VID(vid));
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200358
359out:
360 if (dat_entry)
Sven Eckelmanna6416f92016-01-17 11:01:17 +0100361 batadv_dat_entry_put(dat_entry);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200362}
363
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200364#ifdef CONFIG_BATMAN_ADV_DEBUG
365
366/**
367 * batadv_dbg_arp - print a debug message containing all the ARP packet details
368 * @bat_priv: the bat priv with all the soft interface information
369 * @skb: ARP packet
370 * @type: ARP type
371 * @hdr_size: size of the possible header before the ARP packet
372 * @msg: message to print together with the debugging information
373 */
374static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200375 u16 type, int hdr_size, char *msg)
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200376{
377 struct batadv_unicast_4addr_packet *unicast_4addr_packet;
378 struct batadv_bcast_packet *bcast_pkt;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200379 u8 *orig_addr;
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200380 __be32 ip_src, ip_dst;
381
382 if (msg)
383 batadv_dbg(BATADV_DBG_DAT, bat_priv, "%s\n", msg);
384
385 ip_src = batadv_arp_ip_src(skb, hdr_size);
386 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
387 batadv_dbg(BATADV_DBG_DAT, bat_priv,
388 "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n",
389 batadv_arp_hw_src(skb, hdr_size), &ip_src,
390 batadv_arp_hw_dst(skb, hdr_size), &ip_dst);
391
392 if (hdr_size == 0)
393 return;
394
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200395 unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
396
Simon Wunderlicha40d9b02013-12-02 20:38:31 +0100397 switch (unicast_4addr_packet->u.packet_type) {
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200398 case BATADV_UNICAST:
399 batadv_dbg(BATADV_DBG_DAT, bat_priv,
400 "* encapsulated within a UNICAST packet\n");
401 break;
402 case BATADV_UNICAST_4ADDR:
403 batadv_dbg(BATADV_DBG_DAT, bat_priv,
404 "* encapsulated within a UNICAST_4ADDR packet (src: %pM)\n",
405 unicast_4addr_packet->src);
406 switch (unicast_4addr_packet->subtype) {
407 case BATADV_P_DAT_DHT_PUT:
408 batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_PUT\n");
409 break;
410 case BATADV_P_DAT_DHT_GET:
411 batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_GET\n");
412 break;
413 case BATADV_P_DAT_CACHE_REPLY:
414 batadv_dbg(BATADV_DBG_DAT, bat_priv,
415 "* type: DAT_CACHE_REPLY\n");
416 break;
417 case BATADV_P_DATA:
418 batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DATA\n");
419 break;
420 default:
421 batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: Unknown (%u)!\n",
Simon Wunderlicha40d9b02013-12-02 20:38:31 +0100422 unicast_4addr_packet->u.packet_type);
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200423 }
424 break;
425 case BATADV_BCAST:
426 bcast_pkt = (struct batadv_bcast_packet *)unicast_4addr_packet;
427 orig_addr = bcast_pkt->orig;
428 batadv_dbg(BATADV_DBG_DAT, bat_priv,
429 "* encapsulated within a BCAST packet (src: %pM)\n",
430 orig_addr);
431 break;
432 default:
433 batadv_dbg(BATADV_DBG_DAT, bat_priv,
434 "* encapsulated within an unknown packet type (0x%x)\n",
Simon Wunderlicha40d9b02013-12-02 20:38:31 +0100435 unicast_4addr_packet->u.packet_type);
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200436 }
437}
438
439#else
440
441static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200442 u16 type, int hdr_size, char *msg)
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200443{
444}
445
446#endif /* CONFIG_BATMAN_ADV_DEBUG */
447
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200448/**
Antonio Quartulli785ea112011-11-23 11:35:44 +0100449 * batadv_is_orig_node_eligible - check whether a node can be a DHT candidate
450 * @res: the array with the already selected candidates
451 * @select: number of already selected candidates
452 * @tmp_max: address of the currently evaluated node
453 * @max: current round max address
454 * @last_max: address of the last selected candidate
455 * @candidate: orig_node under evaluation
456 * @max_orig_node: last selected candidate
457 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200458 * Return: true if the node has been elected as next candidate or false
Marek Lindner93178012013-03-10 19:29:15 +0800459 * otherwise.
Antonio Quartulli785ea112011-11-23 11:35:44 +0100460 */
461static bool batadv_is_orig_node_eligible(struct batadv_dat_candidate *res,
462 int select, batadv_dat_addr_t tmp_max,
463 batadv_dat_addr_t max,
464 batadv_dat_addr_t last_max,
465 struct batadv_orig_node *candidate,
466 struct batadv_orig_node *max_orig_node)
467{
468 bool ret = false;
469 int j;
470
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800471 /* check if orig node candidate is running DAT */
Linus Lüssing65d7d4602015-06-16 17:10:22 +0200472 if (!test_bit(BATADV_ORIG_CAPA_HAS_DAT, &candidate->capabilities))
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800473 goto out;
474
Antonio Quartulli785ea112011-11-23 11:35:44 +0100475 /* Check if this node has already been selected... */
476 for (j = 0; j < select; j++)
477 if (res[j].orig_node == candidate)
478 break;
479 /* ..and possibly skip it */
480 if (j < select)
481 goto out;
482 /* sanity check: has it already been selected? This should not happen */
483 if (tmp_max > last_max)
484 goto out;
485 /* check if during this iteration an originator with a closer dht
486 * address has already been found
487 */
488 if (tmp_max < max)
489 goto out;
490 /* this is an hash collision with the temporary selected node. Choose
491 * the one with the lowest address
492 */
Pau Koning816cd5b2013-02-12 00:18:45 +0000493 if ((tmp_max == max) && max_orig_node &&
Antonio Quartulli785ea112011-11-23 11:35:44 +0100494 (batadv_compare_eth(candidate->orig, max_orig_node->orig) > 0))
495 goto out;
496
497 ret = true;
498out:
499 return ret;
500}
501
502/**
503 * batadv_choose_next_candidate - select the next DHT candidate
504 * @bat_priv: the bat priv with all the soft interface information
505 * @cands: candidates array
506 * @select: number of candidates already present in the array
507 * @ip_key: key to look up in the DHT
508 * @last_max: pointer where the address of the selected candidate will be saved
509 */
510static void batadv_choose_next_candidate(struct batadv_priv *bat_priv,
511 struct batadv_dat_candidate *cands,
512 int select, batadv_dat_addr_t ip_key,
513 batadv_dat_addr_t *last_max)
514{
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200515 batadv_dat_addr_t max = 0;
516 batadv_dat_addr_t tmp_max = 0;
Antonio Quartulli785ea112011-11-23 11:35:44 +0100517 struct batadv_orig_node *orig_node, *max_orig_node = NULL;
518 struct batadv_hashtable *hash = bat_priv->orig_hash;
Antonio Quartulli785ea112011-11-23 11:35:44 +0100519 struct hlist_head *head;
520 int i;
521
522 /* if no node is eligible as candidate, leave the candidate type as
523 * NOT_FOUND
524 */
525 cands[select].type = BATADV_DAT_CANDIDATE_NOT_FOUND;
526
Marek Lindner93178012013-03-10 19:29:15 +0800527 /* iterate over the originator list and find the node with the closest
Antonio Quartulli785ea112011-11-23 11:35:44 +0100528 * dat_address which has not been selected yet
529 */
530 for (i = 0; i < hash->size; i++) {
531 head = &hash->table[i];
532
533 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800534 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
Marek Lindner93178012013-03-10 19:29:15 +0800535 /* the dht space is a ring using unsigned addresses */
Antonio Quartulli785ea112011-11-23 11:35:44 +0100536 tmp_max = BATADV_DAT_ADDR_MAX - orig_node->dat_addr +
537 ip_key;
538
539 if (!batadv_is_orig_node_eligible(cands, select,
540 tmp_max, max,
541 *last_max, orig_node,
542 max_orig_node))
543 continue;
544
Sven Eckelmann7c124392016-01-16 10:29:56 +0100545 if (!kref_get_unless_zero(&orig_node->refcount))
Antonio Quartulli785ea112011-11-23 11:35:44 +0100546 continue;
547
548 max = tmp_max;
549 if (max_orig_node)
Sven Eckelmann5d967312016-01-17 11:01:09 +0100550 batadv_orig_node_put(max_orig_node);
Antonio Quartulli785ea112011-11-23 11:35:44 +0100551 max_orig_node = orig_node;
552 }
553 rcu_read_unlock();
554 }
555 if (max_orig_node) {
556 cands[select].type = BATADV_DAT_CANDIDATE_ORIG;
557 cands[select].orig_node = max_orig_node;
558 batadv_dbg(BATADV_DBG_DAT, bat_priv,
559 "dat_select_candidates() %d: selected %pM addr=%u dist=%u\n",
560 select, max_orig_node->orig, max_orig_node->dat_addr,
561 max);
562 }
563 *last_max = max;
564}
565
566/**
Marek Lindner93178012013-03-10 19:29:15 +0800567 * batadv_dat_select_candidates - select the nodes which the DHT message has to
Antonio Quartulli785ea112011-11-23 11:35:44 +0100568 * be sent to
569 * @bat_priv: the bat priv with all the soft interface information
570 * @ip_dst: ipv4 to look up in the DHT
571 *
572 * An originator O is selected if and only if its DHT_ID value is one of three
573 * closest values (from the LEFT, with wrap around if needed) then the hash
574 * value of the key. ip_dst is the key.
575 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200576 * Return: the candidate array of size BATADV_DAT_CANDIDATE_NUM.
Antonio Quartulli785ea112011-11-23 11:35:44 +0100577 */
578static struct batadv_dat_candidate *
579batadv_dat_select_candidates(struct batadv_priv *bat_priv, __be32 ip_dst)
580{
581 int select;
582 batadv_dat_addr_t last_max = BATADV_DAT_ADDR_MAX, ip_key;
583 struct batadv_dat_candidate *res;
Sven Eckelmannb7fe3d42015-11-03 10:05:44 +0100584 struct batadv_dat_entry dat;
Antonio Quartulli785ea112011-11-23 11:35:44 +0100585
586 if (!bat_priv->orig_hash)
587 return NULL;
588
Antonio Quartulli0185dda2014-05-24 06:43:47 +0200589 res = kmalloc_array(BATADV_DAT_CANDIDATES_NUM, sizeof(*res),
590 GFP_ATOMIC);
Antonio Quartulli785ea112011-11-23 11:35:44 +0100591 if (!res)
592 return NULL;
593
Sven Eckelmannb7fe3d42015-11-03 10:05:44 +0100594 dat.ip = ip_dst;
595 dat.vid = 0;
596 ip_key = (batadv_dat_addr_t)batadv_hash_dat(&dat,
Antonio Quartulli785ea112011-11-23 11:35:44 +0100597 BATADV_DAT_ADDR_MAX);
598
599 batadv_dbg(BATADV_DBG_DAT, bat_priv,
600 "dat_select_candidates(): IP=%pI4 hash(IP)=%u\n", &ip_dst,
601 ip_key);
602
603 for (select = 0; select < BATADV_DAT_CANDIDATES_NUM; select++)
604 batadv_choose_next_candidate(bat_priv, res, select, ip_key,
605 &last_max);
606
607 return res;
608}
609
610/**
611 * batadv_dat_send_data - send a payload to the selected candidates
612 * @bat_priv: the bat priv with all the soft interface information
613 * @skb: payload to send
614 * @ip: the DHT key
615 * @packet_subtype: unicast4addr packet subtype to use
616 *
Marek Lindner93178012013-03-10 19:29:15 +0800617 * This function copies the skb with pskb_copy() and is sent as unicast packet
618 * to each of the selected candidates.
Antonio Quartulli785ea112011-11-23 11:35:44 +0100619 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200620 * Return: true if the packet is sent to at least one candidate, false
Marek Lindner93178012013-03-10 19:29:15 +0800621 * otherwise.
Antonio Quartulli785ea112011-11-23 11:35:44 +0100622 */
623static bool batadv_dat_send_data(struct batadv_priv *bat_priv,
624 struct sk_buff *skb, __be32 ip,
625 int packet_subtype)
626{
627 int i;
628 bool ret = false;
629 int send_status;
630 struct batadv_neigh_node *neigh_node = NULL;
631 struct sk_buff *tmp_skb;
632 struct batadv_dat_candidate *cand;
633
634 cand = batadv_dat_select_candidates(bat_priv, ip);
635 if (!cand)
636 goto out;
637
638 batadv_dbg(BATADV_DBG_DAT, bat_priv, "DHT_SEND for %pI4\n", &ip);
639
640 for (i = 0; i < BATADV_DAT_CANDIDATES_NUM; i++) {
641 if (cand[i].type == BATADV_DAT_CANDIDATE_NOT_FOUND)
642 continue;
643
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100644 neigh_node = batadv_orig_router_get(cand[i].orig_node,
645 BATADV_IF_DEFAULT);
Antonio Quartulli785ea112011-11-23 11:35:44 +0100646 if (!neigh_node)
647 goto free_orig;
648
Octavian Purdilabad93e92014-06-12 01:36:26 +0300649 tmp_skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
Martin Hundebøllf097e252013-05-23 16:53:01 +0200650 if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, tmp_skb,
651 cand[i].orig_node,
652 packet_subtype)) {
Antonio Quartulli785ea112011-11-23 11:35:44 +0100653 kfree_skb(tmp_skb);
654 goto free_neigh;
655 }
656
Antonio Quartulli95d39272016-01-16 16:40:15 +0800657 send_status = batadv_send_unicast_skb(tmp_skb, neigh_node);
Martin Hundebøll4046b242012-04-20 17:02:45 +0200658 if (send_status == NET_XMIT_SUCCESS) {
659 /* count the sent packet */
660 switch (packet_subtype) {
661 case BATADV_P_DAT_DHT_GET:
662 batadv_inc_counter(bat_priv,
663 BATADV_CNT_DAT_GET_TX);
664 break;
665 case BATADV_P_DAT_DHT_PUT:
666 batadv_inc_counter(bat_priv,
667 BATADV_CNT_DAT_PUT_TX);
668 break;
669 }
670
Antonio Quartulli785ea112011-11-23 11:35:44 +0100671 /* packet sent to a candidate: return true */
672 ret = true;
Martin Hundebøll4046b242012-04-20 17:02:45 +0200673 }
Antonio Quartulli785ea112011-11-23 11:35:44 +0100674free_neigh:
Sven Eckelmann25bb2502016-01-17 11:01:11 +0100675 batadv_neigh_node_put(neigh_node);
Antonio Quartulli785ea112011-11-23 11:35:44 +0100676free_orig:
Sven Eckelmann5d967312016-01-17 11:01:09 +0100677 batadv_orig_node_put(cand[i].orig_node);
Antonio Quartulli785ea112011-11-23 11:35:44 +0100678 }
679
680out:
681 kfree(cand);
682 return ret;
683}
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200684
685/**
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800686 * batadv_dat_tvlv_container_update - update the dat tvlv container after dat
687 * setting change
688 * @bat_priv: the bat priv with all the soft interface information
689 */
690static void batadv_dat_tvlv_container_update(struct batadv_priv *bat_priv)
691{
692 char dat_mode;
693
694 dat_mode = atomic_read(&bat_priv->distributed_arp_table);
695
696 switch (dat_mode) {
697 case 0:
698 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_DAT, 1);
699 break;
700 case 1:
701 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_DAT, 1,
702 NULL, 0);
703 break;
704 }
705}
706
707/**
708 * batadv_dat_status_update - update the dat tvlv container after dat
709 * setting change
710 * @net_dev: the soft interface net device
711 */
712void batadv_dat_status_update(struct net_device *net_dev)
713{
714 struct batadv_priv *bat_priv = netdev_priv(net_dev);
Antonio Quartullif1386942014-05-10 18:56:37 +0200715
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800716 batadv_dat_tvlv_container_update(bat_priv);
717}
718
719/**
720 * batadv_gw_tvlv_ogm_handler_v1 - process incoming dat tvlv container
721 * @bat_priv: the bat priv with all the soft interface information
722 * @orig: the orig_node of the ogm
723 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
724 * @tvlv_value: tvlv buffer containing the gateway data
725 * @tvlv_value_len: tvlv buffer length
726 */
727static void batadv_dat_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
728 struct batadv_orig_node *orig,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200729 u8 flags,
730 void *tvlv_value, u16 tvlv_value_len)
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800731{
732 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
Linus Lüssing65d7d4602015-06-16 17:10:22 +0200733 clear_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800734 else
Linus Lüssing65d7d4602015-06-16 17:10:22 +0200735 set_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800736}
737
738/**
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200739 * batadv_dat_hash_free - free the local DAT hash table
740 * @bat_priv: the bat priv with all the soft interface information
741 */
742static void batadv_dat_hash_free(struct batadv_priv *bat_priv)
743{
Antonio Quartulli33af49a2012-08-08 18:50:57 +0200744 if (!bat_priv->dat.hash)
745 return;
746
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200747 __batadv_dat_purge(bat_priv, NULL);
748
749 batadv_hash_destroy(bat_priv->dat.hash);
750
751 bat_priv->dat.hash = NULL;
752}
753
754/**
755 * batadv_dat_init - initialise the DAT internals
756 * @bat_priv: the bat priv with all the soft interface information
Antonio Quartullife13c2a2015-11-17 16:40:51 +0800757 *
758 * Return: 0 in case of success, a negative error code otherwise
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200759 */
760int batadv_dat_init(struct batadv_priv *bat_priv)
761{
762 if (bat_priv->dat.hash)
763 return 0;
764
765 bat_priv->dat.hash = batadv_hash_new(1024);
766
767 if (!bat_priv->dat.hash)
768 return -ENOMEM;
769
770 batadv_dat_start_timer(bat_priv);
771
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800772 batadv_tvlv_handler_register(bat_priv, batadv_dat_tvlv_ogm_handler_v1,
773 NULL, BATADV_TVLV_DAT, 1,
774 BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
775 batadv_dat_tvlv_container_update(bat_priv);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200776 return 0;
777}
778
779/**
780 * batadv_dat_free - free the DAT internals
781 * @bat_priv: the bat priv with all the soft interface information
782 */
783void batadv_dat_free(struct batadv_priv *bat_priv)
784{
Marek Lindner17cf0ea2013-04-23 21:39:59 +0800785 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_DAT, 1);
786 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_DAT, 1);
787
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200788 cancel_delayed_work_sync(&bat_priv->dat.work);
789
790 batadv_dat_hash_free(bat_priv);
791}
792
793/**
794 * batadv_dat_cache_seq_print_text - print the local DAT hash table
795 * @seq: seq file to print on
796 * @offset: not used
Antonio Quartullife13c2a2015-11-17 16:40:51 +0800797 *
798 * Return: always 0
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200799 */
800int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset)
801{
802 struct net_device *net_dev = (struct net_device *)seq->private;
803 struct batadv_priv *bat_priv = netdev_priv(net_dev);
804 struct batadv_hashtable *hash = bat_priv->dat.hash;
805 struct batadv_dat_entry *dat_entry;
806 struct batadv_hard_iface *primary_if;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200807 struct hlist_head *head;
808 unsigned long last_seen_jiffies;
809 int last_seen_msecs, last_seen_secs, last_seen_mins;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200810 u32 i;
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200811
812 primary_if = batadv_seq_print_text_primary_if_get(seq);
813 if (!primary_if)
814 goto out;
815
816 seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name);
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200817 seq_printf(seq, " %-7s %-9s %4s %11s\n", "IPv4",
818 "MAC", "VID", "last-seen");
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200819
820 for (i = 0; i < hash->size; i++) {
821 head = &hash->table[i];
822
823 rcu_read_lock();
Sasha Levinb67bfe02013-02-27 17:06:00 -0800824 hlist_for_each_entry_rcu(dat_entry, head, hash_entry) {
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200825 last_seen_jiffies = jiffies - dat_entry->last_update;
826 last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
827 last_seen_mins = last_seen_msecs / 60000;
828 last_seen_msecs = last_seen_msecs % 60000;
829 last_seen_secs = last_seen_msecs / 1000;
830
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200831 seq_printf(seq, " * %15pI4 %14pM %4i %6i:%02i\n",
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200832 &dat_entry->ip, dat_entry->mac_addr,
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200833 BATADV_PRINT_VID(dat_entry->vid),
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200834 last_seen_mins, last_seen_secs);
835 }
836 rcu_read_unlock();
837 }
838
839out:
840 if (primary_if)
Sven Eckelmann82047ad2016-01-17 11:01:10 +0100841 batadv_hardif_put(primary_if);
Antonio Quartulli2f1dfbe2012-06-30 20:01:19 +0200842 return 0;
843}
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200844
845/**
846 * batadv_arp_get_type - parse an ARP packet and gets the type
847 * @bat_priv: the bat priv with all the soft interface information
848 * @skb: packet to analyse
849 * @hdr_size: size of the possible header before the ARP packet in the skb
850 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200851 * Return: the ARP type if the skb contains a valid ARP packet, 0 otherwise.
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200852 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200853static u16 batadv_arp_get_type(struct batadv_priv *bat_priv,
854 struct sk_buff *skb, int hdr_size)
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200855{
856 struct arphdr *arphdr;
857 struct ethhdr *ethhdr;
858 __be32 ip_src, ip_dst;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200859 u8 *hw_src, *hw_dst;
860 u16 type = 0;
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200861
862 /* pull the ethernet header */
863 if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN)))
864 goto out;
865
866 ethhdr = (struct ethhdr *)(skb->data + hdr_size);
867
868 if (ethhdr->h_proto != htons(ETH_P_ARP))
869 goto out;
870
871 /* pull the ARP payload */
872 if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN +
873 arp_hdr_len(skb->dev))))
874 goto out;
875
876 arphdr = (struct arphdr *)(skb->data + hdr_size + ETH_HLEN);
877
Marek Lindner93178012013-03-10 19:29:15 +0800878 /* check whether the ARP packet carries a valid IP information */
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200879 if (arphdr->ar_hrd != htons(ARPHRD_ETHER))
880 goto out;
881
882 if (arphdr->ar_pro != htons(ETH_P_IP))
883 goto out;
884
885 if (arphdr->ar_hln != ETH_ALEN)
886 goto out;
887
888 if (arphdr->ar_pln != 4)
889 goto out;
890
891 /* Check for bad reply/request. If the ARP message is not sane, DAT
892 * will simply ignore it
893 */
894 ip_src = batadv_arp_ip_src(skb, hdr_size);
895 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
896 if (ipv4_is_loopback(ip_src) || ipv4_is_multicast(ip_src) ||
Matthias Schiffer757dd822013-01-24 18:18:26 +0100897 ipv4_is_loopback(ip_dst) || ipv4_is_multicast(ip_dst) ||
898 ipv4_is_zeronet(ip_src) || ipv4_is_lbcast(ip_src) ||
899 ipv4_is_zeronet(ip_dst) || ipv4_is_lbcast(ip_dst))
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200900 goto out;
901
Matthias Schifferb618ad12013-01-24 18:18:27 +0100902 hw_src = batadv_arp_hw_src(skb, hdr_size);
903 if (is_zero_ether_addr(hw_src) || is_multicast_ether_addr(hw_src))
904 goto out;
905
Marek Lindner93178012013-03-10 19:29:15 +0800906 /* don't care about the destination MAC address in ARP requests */
Matthias Schifferb618ad12013-01-24 18:18:27 +0100907 if (arphdr->ar_op != htons(ARPOP_REQUEST)) {
908 hw_dst = batadv_arp_hw_dst(skb, hdr_size);
909 if (is_zero_ether_addr(hw_dst) ||
910 is_multicast_ether_addr(hw_dst))
911 goto out;
912 }
913
Antonio Quartulli5c3a0e52011-06-02 12:29:51 +0200914 type = ntohs(arphdr->ar_op);
915out:
916 return type;
917}
Antonio Quartullic384ea32011-06-26 03:37:18 +0200918
919/**
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200920 * batadv_dat_get_vid - extract the VLAN identifier from skb if any
921 * @skb: the buffer containing the packet to extract the VID from
922 * @hdr_size: the size of the batman-adv header encapsulating the packet
923 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200924 * Return: If the packet embedded in the skb is vlan tagged this function
925 * returns the VID with the BATADV_VLAN_HAS_TAG flag. Otherwise BATADV_NO_FLAGS
926 * is returned.
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200927 */
928static unsigned short batadv_dat_get_vid(struct sk_buff *skb, int *hdr_size)
929{
930 unsigned short vid;
931
932 vid = batadv_get_vid(skb, *hdr_size);
933
934 /* ARP parsing functions jump forward of hdr_size + ETH_HLEN.
935 * If the header contained in the packet is a VLAN one (which is longer)
936 * hdr_size is updated so that the functions will still skip the
937 * correct amount of bytes.
938 */
939 if (vid & BATADV_VLAN_HAS_TAG)
940 *hdr_size += VLAN_HLEN;
941
942 return vid;
943}
944
945/**
Antonio Quartullic384ea32011-06-26 03:37:18 +0200946 * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to
947 * answer using DAT
948 * @bat_priv: the bat priv with all the soft interface information
949 * @skb: packet to check
950 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200951 * Return: true if the message has been sent to the dht candidates, false
Marek Lindner93178012013-03-10 19:29:15 +0800952 * otherwise. In case of a positive return value the message has to be enqueued
953 * to permit the fallback.
Antonio Quartullic384ea32011-06-26 03:37:18 +0200954 */
955bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
956 struct sk_buff *skb)
957{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200958 u16 type = 0;
Antonio Quartullic384ea32011-06-26 03:37:18 +0200959 __be32 ip_dst, ip_src;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200960 u8 *hw_src;
Antonio Quartullic384ea32011-06-26 03:37:18 +0200961 bool ret = false;
962 struct batadv_dat_entry *dat_entry = NULL;
963 struct sk_buff *skb_new;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200964 int hdr_size = 0;
965 unsigned short vid;
Antonio Quartullic384ea32011-06-26 03:37:18 +0200966
Antonio Quartulli33af49a2012-08-08 18:50:57 +0200967 if (!atomic_read(&bat_priv->distributed_arp_table))
968 goto out;
969
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200970 vid = batadv_dat_get_vid(skb, &hdr_size);
971
972 type = batadv_arp_get_type(bat_priv, skb, hdr_size);
Antonio Quartullic384ea32011-06-26 03:37:18 +0200973 /* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast
974 * message to the selected DHT candidates
975 */
976 if (type != ARPOP_REQUEST)
977 goto out;
978
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200979 batadv_dbg_arp(bat_priv, skb, type, hdr_size,
980 "Parsing outgoing ARP REQUEST");
Antonio Quartullic384ea32011-06-26 03:37:18 +0200981
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200982 ip_src = batadv_arp_ip_src(skb, hdr_size);
983 hw_src = batadv_arp_hw_src(skb, hdr_size);
984 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
Antonio Quartullic384ea32011-06-26 03:37:18 +0200985
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200986 batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +0200987
Antonio Quartullibe1db4f2013-06-04 12:11:43 +0200988 dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +0200989 if (dat_entry) {
Antonio Quartulli88e48d72013-05-09 09:35:45 +0200990 /* If the ARP request is destined for a local client the local
991 * client will answer itself. DAT would only generate a
992 * duplicate packet.
993 *
994 * Moreover, if the soft-interface is enslaved into a bridge, an
995 * additional DAT answer may trigger kernel warnings about
996 * a packet coming from the wrong port.
997 */
Antonio Quartullicc2f3382014-03-29 17:27:38 +0100998 if (batadv_is_my_client(bat_priv, dat_entry->mac_addr, vid)) {
Antonio Quartulli88e48d72013-05-09 09:35:45 +0200999 ret = true;
1000 goto out;
1001 }
1002
Antonio Quartullic384ea32011-06-26 03:37:18 +02001003 skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
Marek Lindner736292c2013-01-12 19:19:06 +08001004 bat_priv->soft_iface, ip_dst, hw_src,
Antonio Quartullic384ea32011-06-26 03:37:18 +02001005 dat_entry->mac_addr, hw_src);
1006 if (!skb_new)
1007 goto out;
1008
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001009 if (vid & BATADV_VLAN_HAS_TAG)
1010 skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
1011 vid & VLAN_VID_MASK);
1012
Antonio Quartullic384ea32011-06-26 03:37:18 +02001013 skb_reset_mac_header(skb_new);
1014 skb_new->protocol = eth_type_trans(skb_new,
Marek Lindner736292c2013-01-12 19:19:06 +08001015 bat_priv->soft_iface);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001016 bat_priv->stats.rx_packets++;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001017 bat_priv->stats.rx_bytes += skb->len + ETH_HLEN + hdr_size;
Marek Lindner736292c2013-01-12 19:19:06 +08001018 bat_priv->soft_iface->last_rx = jiffies;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001019
1020 netif_rx(skb_new);
1021 batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n");
1022 ret = true;
1023 } else {
Marek Lindner93178012013-03-10 19:29:15 +08001024 /* Send the request to the DHT */
Antonio Quartullic384ea32011-06-26 03:37:18 +02001025 ret = batadv_dat_send_data(bat_priv, skb, ip_dst,
1026 BATADV_P_DAT_DHT_GET);
1027 }
1028out:
1029 if (dat_entry)
Sven Eckelmanna6416f92016-01-17 11:01:17 +01001030 batadv_dat_entry_put(dat_entry);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001031 return ret;
1032}
1033
1034/**
1035 * batadv_dat_snoop_incoming_arp_request - snoop the ARP request and try to
1036 * answer using the local DAT storage
1037 * @bat_priv: the bat priv with all the soft interface information
1038 * @skb: packet to check
1039 * @hdr_size: size of the encapsulation header
1040 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001041 * Return: true if the request has been answered, false otherwise.
Antonio Quartullic384ea32011-06-26 03:37:18 +02001042 */
1043bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
1044 struct sk_buff *skb, int hdr_size)
1045{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001046 u16 type;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001047 __be32 ip_src, ip_dst;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001048 u8 *hw_src;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001049 struct sk_buff *skb_new;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001050 struct batadv_dat_entry *dat_entry = NULL;
1051 bool ret = false;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001052 unsigned short vid;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001053 int err;
1054
Antonio Quartulli33af49a2012-08-08 18:50:57 +02001055 if (!atomic_read(&bat_priv->distributed_arp_table))
1056 goto out;
1057
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001058 vid = batadv_dat_get_vid(skb, &hdr_size);
1059
Antonio Quartullic384ea32011-06-26 03:37:18 +02001060 type = batadv_arp_get_type(bat_priv, skb, hdr_size);
1061 if (type != ARPOP_REQUEST)
1062 goto out;
1063
1064 hw_src = batadv_arp_hw_src(skb, hdr_size);
1065 ip_src = batadv_arp_ip_src(skb, hdr_size);
1066 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
1067
1068 batadv_dbg_arp(bat_priv, skb, type, hdr_size,
1069 "Parsing incoming ARP REQUEST");
1070
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001071 batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001072
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001073 dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001074 if (!dat_entry)
1075 goto out;
1076
Antonio Quartullic384ea32011-06-26 03:37:18 +02001077 skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
Marek Lindner736292c2013-01-12 19:19:06 +08001078 bat_priv->soft_iface, ip_dst, hw_src,
Antonio Quartullic384ea32011-06-26 03:37:18 +02001079 dat_entry->mac_addr, hw_src);
1080
1081 if (!skb_new)
1082 goto out;
1083
Linus Lüssing927c2ed2014-01-19 22:22:45 +01001084 /* the rest of the TX path assumes that the mac_header offset pointing
1085 * to the inner Ethernet header has been set, therefore reset it now.
1086 */
1087 skb_reset_mac_header(skb_new);
1088
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001089 if (vid & BATADV_VLAN_HAS_TAG)
1090 skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
1091 vid & VLAN_VID_MASK);
1092
Marek Lindner93178012013-03-10 19:29:15 +08001093 /* To preserve backwards compatibility, the node has choose the outgoing
1094 * format based on the incoming request packet type. The assumption is
1095 * that a node not using the 4addr packet format doesn't support it.
Antonio Quartullic384ea32011-06-26 03:37:18 +02001096 */
1097 if (hdr_size == sizeof(struct batadv_unicast_4addr_packet))
Linus Lüssinge300d312013-07-03 10:40:00 +02001098 err = batadv_send_skb_via_tt_4addr(bat_priv, skb_new,
1099 BATADV_P_DAT_CACHE_REPLY,
Antonio Quartulli6c413b12013-11-05 19:31:08 +01001100 NULL, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001101 else
Antonio Quartulli6c413b12013-11-05 19:31:08 +01001102 err = batadv_send_skb_via_tt(bat_priv, skb_new, NULL, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001103
Linus Lüssinge300d312013-07-03 10:40:00 +02001104 if (err != NET_XMIT_DROP) {
Martin Hundebøll4046b242012-04-20 17:02:45 +02001105 batadv_inc_counter(bat_priv, BATADV_CNT_DAT_CACHED_REPLY_TX);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001106 ret = true;
Martin Hundebøll4046b242012-04-20 17:02:45 +02001107 }
Antonio Quartullic384ea32011-06-26 03:37:18 +02001108out:
1109 if (dat_entry)
Sven Eckelmanna6416f92016-01-17 11:01:17 +01001110 batadv_dat_entry_put(dat_entry);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001111 if (ret)
1112 kfree_skb(skb);
1113 return ret;
1114}
1115
1116/**
1117 * batadv_dat_snoop_outgoing_arp_reply - snoop the ARP reply and fill the DHT
1118 * @bat_priv: the bat priv with all the soft interface information
1119 * @skb: packet to check
1120 */
1121void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
1122 struct sk_buff *skb)
1123{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001124 u16 type;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001125 __be32 ip_src, ip_dst;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001126 u8 *hw_src, *hw_dst;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001127 int hdr_size = 0;
1128 unsigned short vid;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001129
Antonio Quartulli33af49a2012-08-08 18:50:57 +02001130 if (!atomic_read(&bat_priv->distributed_arp_table))
1131 return;
1132
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001133 vid = batadv_dat_get_vid(skb, &hdr_size);
1134
1135 type = batadv_arp_get_type(bat_priv, skb, hdr_size);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001136 if (type != ARPOP_REPLY)
1137 return;
1138
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001139 batadv_dbg_arp(bat_priv, skb, type, hdr_size,
1140 "Parsing outgoing ARP REPLY");
Antonio Quartullic384ea32011-06-26 03:37:18 +02001141
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001142 hw_src = batadv_arp_hw_src(skb, hdr_size);
1143 ip_src = batadv_arp_ip_src(skb, hdr_size);
1144 hw_dst = batadv_arp_hw_dst(skb, hdr_size);
1145 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001146
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001147 batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid);
1148 batadv_dat_entry_add(bat_priv, ip_dst, hw_dst, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001149
1150 /* Send the ARP reply to the candidates for both the IP addresses that
Marek Lindner93178012013-03-10 19:29:15 +08001151 * the node obtained from the ARP reply
Antonio Quartullic384ea32011-06-26 03:37:18 +02001152 */
1153 batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT);
1154 batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT);
1155}
Antonio Quartulliaa143d22014-09-01 14:37:27 +02001156
Antonio Quartullic384ea32011-06-26 03:37:18 +02001157/**
1158 * batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local
1159 * DAT storage only
1160 * @bat_priv: the bat priv with all the soft interface information
1161 * @skb: packet to check
Marek Lindner93178012013-03-10 19:29:15 +08001162 * @hdr_size: size of the encapsulation header
Antonio Quartullif202a662015-06-16 21:06:24 +02001163 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001164 * Return: true if the packet was snooped and consumed by DAT. False if the
Antonio Quartullif202a662015-06-16 21:06:24 +02001165 * packet has to be delivered to the interface
Antonio Quartullic384ea32011-06-26 03:37:18 +02001166 */
1167bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
1168 struct sk_buff *skb, int hdr_size)
1169{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001170 u16 type;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001171 __be32 ip_src, ip_dst;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001172 u8 *hw_src, *hw_dst;
Antonio Quartullif202a662015-06-16 21:06:24 +02001173 bool dropped = false;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001174 unsigned short vid;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001175
Antonio Quartulli33af49a2012-08-08 18:50:57 +02001176 if (!atomic_read(&bat_priv->distributed_arp_table))
1177 goto out;
1178
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001179 vid = batadv_dat_get_vid(skb, &hdr_size);
1180
Antonio Quartullic384ea32011-06-26 03:37:18 +02001181 type = batadv_arp_get_type(bat_priv, skb, hdr_size);
1182 if (type != ARPOP_REPLY)
1183 goto out;
1184
1185 batadv_dbg_arp(bat_priv, skb, type, hdr_size,
1186 "Parsing incoming ARP REPLY");
1187
1188 hw_src = batadv_arp_hw_src(skb, hdr_size);
1189 ip_src = batadv_arp_ip_src(skb, hdr_size);
1190 hw_dst = batadv_arp_hw_dst(skb, hdr_size);
1191 ip_dst = batadv_arp_ip_dst(skb, hdr_size);
1192
1193 /* Update our internal cache with both the IP addresses the node got
1194 * within the ARP reply
1195 */
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001196 batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid);
1197 batadv_dat_entry_add(bat_priv, ip_dst, hw_dst, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001198
1199 /* if this REPLY is directed to a client of mine, let's deliver the
1200 * packet to the interface
1201 */
Antonio Quartullif202a662015-06-16 21:06:24 +02001202 dropped = !batadv_is_my_client(bat_priv, hw_dst, vid);
1203
1204 /* if this REPLY is sent on behalf of a client of mine, let's drop the
1205 * packet because the client will reply by itself
1206 */
1207 dropped |= batadv_is_my_client(bat_priv, hw_src, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001208out:
Antonio Quartullif202a662015-06-16 21:06:24 +02001209 if (dropped)
Matthias Schiffer0d15bec2013-01-23 18:11:53 +01001210 kfree_skb(skb);
Antonio Quartullif202a662015-06-16 21:06:24 +02001211 /* if dropped == false -> deliver to the interface */
1212 return dropped;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001213}
1214
1215/**
1216 * batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped
Marek Lindner93178012013-03-10 19:29:15 +08001217 * (because the node has already obtained the reply via DAT) or not
Antonio Quartullic384ea32011-06-26 03:37:18 +02001218 * @bat_priv: the bat priv with all the soft interface information
1219 * @forw_packet: the broadcast packet
1220 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001221 * Return: true if the node can drop the packet, false otherwise.
Antonio Quartullic384ea32011-06-26 03:37:18 +02001222 */
1223bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
1224 struct batadv_forw_packet *forw_packet)
1225{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001226 u16 type;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001227 __be32 ip_dst;
1228 struct batadv_dat_entry *dat_entry = NULL;
1229 bool ret = false;
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001230 int hdr_size = sizeof(struct batadv_bcast_packet);
1231 unsigned short vid;
Antonio Quartullic384ea32011-06-26 03:37:18 +02001232
Antonio Quartulli33af49a2012-08-08 18:50:57 +02001233 if (!atomic_read(&bat_priv->distributed_arp_table))
1234 goto out;
1235
Antonio Quartullic384ea32011-06-26 03:37:18 +02001236 /* If this packet is an ARP_REQUEST and the node already has the
1237 * information that it is going to ask, then the packet can be dropped
1238 */
1239 if (forw_packet->num_packets)
1240 goto out;
1241
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001242 vid = batadv_dat_get_vid(forw_packet->skb, &hdr_size);
1243
1244 type = batadv_arp_get_type(bat_priv, forw_packet->skb, hdr_size);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001245 if (type != ARPOP_REQUEST)
1246 goto out;
1247
Antonio Quartullibe1db4f2013-06-04 12:11:43 +02001248 ip_dst = batadv_arp_ip_dst(forw_packet->skb, hdr_size);
1249 dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst, vid);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001250 /* check if the node already got this entry */
1251 if (!dat_entry) {
1252 batadv_dbg(BATADV_DBG_DAT, bat_priv,
1253 "ARP Request for %pI4: fallback\n", &ip_dst);
1254 goto out;
1255 }
1256
1257 batadv_dbg(BATADV_DBG_DAT, bat_priv,
1258 "ARP Request for %pI4: fallback prevented\n", &ip_dst);
1259 ret = true;
1260
1261out:
1262 if (dat_entry)
Sven Eckelmanna6416f92016-01-17 11:01:17 +01001263 batadv_dat_entry_put(dat_entry);
Antonio Quartullic384ea32011-06-26 03:37:18 +02001264 return ret;
1265}