Antonio Quartulli | 0b87393 | 2013-01-04 03:05:31 +0100 | [diff] [blame] | 1 | /* Copyright (C) 2011-2013 B.A.T.M.A.N. contributors: |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 2 | * |
| 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 |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 17 | * 02110-1301, USA |
| 18 | */ |
| 19 | |
| 20 | #include <linux/if_ether.h> |
| 21 | #include <linux/if_arp.h> |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 22 | #include <net/arp.h> |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 23 | |
| 24 | #include "main.h" |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 25 | #include "hash.h" |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 26 | #include "distributed-arp-table.h" |
| 27 | #include "hard-interface.h" |
| 28 | #include "originator.h" |
| 29 | #include "send.h" |
| 30 | #include "types.h" |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 31 | #include "translation-table.h" |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 32 | |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 33 | static void batadv_dat_purge(struct work_struct *work); |
| 34 | |
| 35 | /** |
| 36 | * batadv_dat_start_timer - initialise the DAT periodic worker |
| 37 | * @bat_priv: the bat priv with all the soft interface information |
| 38 | */ |
| 39 | static void batadv_dat_start_timer(struct batadv_priv *bat_priv) |
| 40 | { |
| 41 | INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge); |
| 42 | queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work, |
| 43 | msecs_to_jiffies(10000)); |
| 44 | } |
| 45 | |
| 46 | /** |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 47 | * batadv_dat_entry_free_ref - decrement the dat_entry refcounter and possibly |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 48 | * free it |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 49 | * @dat_entry: the entry to free |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 50 | */ |
| 51 | static void batadv_dat_entry_free_ref(struct batadv_dat_entry *dat_entry) |
| 52 | { |
| 53 | if (atomic_dec_and_test(&dat_entry->refcount)) |
| 54 | kfree_rcu(dat_entry, rcu); |
| 55 | } |
| 56 | |
| 57 | /** |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 58 | * batadv_dat_to_purge - check whether a dat_entry has to be purged or not |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 59 | * @dat_entry: the entry to check |
| 60 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 61 | * Returns true if the entry has to be purged now, false otherwise. |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 62 | */ |
| 63 | static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry) |
| 64 | { |
| 65 | return batadv_has_timed_out(dat_entry->last_update, |
| 66 | BATADV_DAT_ENTRY_TIMEOUT); |
| 67 | } |
| 68 | |
| 69 | /** |
| 70 | * __batadv_dat_purge - delete entries from the DAT local storage |
| 71 | * @bat_priv: the bat priv with all the soft interface information |
| 72 | * @to_purge: function in charge to decide whether an entry has to be purged or |
| 73 | * not. This function takes the dat_entry as argument and has to |
| 74 | * returns a boolean value: true is the entry has to be deleted, |
| 75 | * false otherwise |
| 76 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 77 | * Loops over each entry in the DAT local storage and deletes it if and only if |
| 78 | * the to_purge function passed as argument returns true. |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 79 | */ |
| 80 | static void __batadv_dat_purge(struct batadv_priv *bat_priv, |
| 81 | bool (*to_purge)(struct batadv_dat_entry *)) |
| 82 | { |
| 83 | spinlock_t *list_lock; /* protects write access to the hash lists */ |
| 84 | struct batadv_dat_entry *dat_entry; |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 85 | struct hlist_node *node_tmp; |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 86 | struct hlist_head *head; |
| 87 | uint32_t i; |
| 88 | |
| 89 | if (!bat_priv->dat.hash) |
| 90 | return; |
| 91 | |
| 92 | for (i = 0; i < bat_priv->dat.hash->size; i++) { |
| 93 | head = &bat_priv->dat.hash->table[i]; |
| 94 | list_lock = &bat_priv->dat.hash->list_locks[i]; |
| 95 | |
| 96 | spin_lock_bh(list_lock); |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 97 | hlist_for_each_entry_safe(dat_entry, node_tmp, head, |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 98 | hash_entry) { |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 99 | /* if a helper function has been passed as parameter, |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 100 | * ask it if the entry has to be purged or not |
| 101 | */ |
| 102 | if (to_purge && !to_purge(dat_entry)) |
| 103 | continue; |
| 104 | |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 105 | hlist_del_rcu(&dat_entry->hash_entry); |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 106 | batadv_dat_entry_free_ref(dat_entry); |
| 107 | } |
| 108 | spin_unlock_bh(list_lock); |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * batadv_dat_purge - periodic task that deletes old entries from the local DAT |
| 114 | * hash table |
| 115 | * @work: kernel work struct |
| 116 | */ |
| 117 | static void batadv_dat_purge(struct work_struct *work) |
| 118 | { |
| 119 | struct delayed_work *delayed_work; |
| 120 | struct batadv_priv_dat *priv_dat; |
| 121 | struct batadv_priv *bat_priv; |
| 122 | |
| 123 | delayed_work = container_of(work, struct delayed_work, work); |
| 124 | priv_dat = container_of(delayed_work, struct batadv_priv_dat, work); |
| 125 | bat_priv = container_of(priv_dat, struct batadv_priv, dat); |
| 126 | |
| 127 | __batadv_dat_purge(bat_priv, batadv_dat_to_purge); |
| 128 | batadv_dat_start_timer(bat_priv); |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * batadv_compare_dat - comparing function used in the local DAT hash table |
| 133 | * @node: node in the local table |
| 134 | * @data2: second object to compare the node to |
| 135 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 136 | * Returns 1 if the two entries are the same, 0 otherwise. |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 137 | */ |
| 138 | static int batadv_compare_dat(const struct hlist_node *node, const void *data2) |
| 139 | { |
| 140 | const void *data1 = container_of(node, struct batadv_dat_entry, |
| 141 | hash_entry); |
| 142 | |
| 143 | return (memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0); |
| 144 | } |
| 145 | |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 146 | /** |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 147 | * batadv_arp_hw_src - extract the hw_src field from an ARP packet |
| 148 | * @skb: ARP packet |
| 149 | * @hdr_size: size of the possible header before the ARP packet |
| 150 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 151 | * Returns the value of the hw_src field in the ARP packet. |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 152 | */ |
| 153 | static uint8_t *batadv_arp_hw_src(struct sk_buff *skb, int hdr_size) |
| 154 | { |
| 155 | uint8_t *addr; |
| 156 | |
| 157 | addr = (uint8_t *)(skb->data + hdr_size); |
| 158 | addr += ETH_HLEN + sizeof(struct arphdr); |
| 159 | |
| 160 | return addr; |
| 161 | } |
| 162 | |
| 163 | /** |
| 164 | * batadv_arp_ip_src - extract the ip_src field from an ARP packet |
| 165 | * @skb: ARP packet |
| 166 | * @hdr_size: size of the possible header before the ARP packet |
| 167 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 168 | * Returns the value of the ip_src field in the ARP packet. |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 169 | */ |
| 170 | static __be32 batadv_arp_ip_src(struct sk_buff *skb, int hdr_size) |
| 171 | { |
| 172 | return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN); |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * batadv_arp_hw_dst - extract the hw_dst field from an ARP packet |
| 177 | * @skb: ARP packet |
| 178 | * @hdr_size: size of the possible header before the ARP packet |
| 179 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 180 | * Returns the value of the hw_dst field in the ARP packet. |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 181 | */ |
| 182 | static uint8_t *batadv_arp_hw_dst(struct sk_buff *skb, int hdr_size) |
| 183 | { |
| 184 | return batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN + 4; |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * batadv_arp_ip_dst - extract the ip_dst field from an ARP packet |
| 189 | * @skb: ARP packet |
| 190 | * @hdr_size: size of the possible header before the ARP packet |
| 191 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 192 | * Returns the value of the ip_dst field in the ARP packet. |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 193 | */ |
| 194 | static __be32 batadv_arp_ip_dst(struct sk_buff *skb, int hdr_size) |
| 195 | { |
| 196 | return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN * 2 + 4); |
| 197 | } |
| 198 | |
| 199 | /** |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 200 | * batadv_hash_dat - compute the hash value for an IP address |
| 201 | * @data: data to hash |
| 202 | * @size: size of the hash table |
| 203 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 204 | * Returns the selected index in the hash table for the given data. |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 205 | */ |
| 206 | static uint32_t batadv_hash_dat(const void *data, uint32_t size) |
| 207 | { |
| 208 | const unsigned char *key = data; |
| 209 | uint32_t hash = 0; |
| 210 | size_t i; |
| 211 | |
| 212 | for (i = 0; i < 4; i++) { |
| 213 | hash += key[i]; |
| 214 | hash += (hash << 10); |
| 215 | hash ^= (hash >> 6); |
| 216 | } |
| 217 | |
| 218 | hash += (hash << 3); |
| 219 | hash ^= (hash >> 11); |
| 220 | hash += (hash << 15); |
| 221 | |
| 222 | return hash % size; |
| 223 | } |
| 224 | |
| 225 | /** |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 226 | * batadv_dat_entry_hash_find - look for a given dat_entry in the local hash |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 227 | * table |
| 228 | * @bat_priv: the bat priv with all the soft interface information |
| 229 | * @ip: search key |
| 230 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 231 | * Returns the dat_entry if found, NULL otherwise. |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 232 | */ |
| 233 | static struct batadv_dat_entry * |
| 234 | batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip) |
| 235 | { |
| 236 | struct hlist_head *head; |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 237 | struct batadv_dat_entry *dat_entry, *dat_entry_tmp = NULL; |
| 238 | struct batadv_hashtable *hash = bat_priv->dat.hash; |
| 239 | uint32_t index; |
| 240 | |
| 241 | if (!hash) |
| 242 | return NULL; |
| 243 | |
| 244 | index = batadv_hash_dat(&ip, hash->size); |
| 245 | head = &hash->table[index]; |
| 246 | |
| 247 | rcu_read_lock(); |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 248 | hlist_for_each_entry_rcu(dat_entry, head, hash_entry) { |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 249 | if (dat_entry->ip != ip) |
| 250 | continue; |
| 251 | |
| 252 | if (!atomic_inc_not_zero(&dat_entry->refcount)) |
| 253 | continue; |
| 254 | |
| 255 | dat_entry_tmp = dat_entry; |
| 256 | break; |
| 257 | } |
| 258 | rcu_read_unlock(); |
| 259 | |
| 260 | return dat_entry_tmp; |
| 261 | } |
| 262 | |
| 263 | /** |
| 264 | * batadv_dat_entry_add - add a new dat entry or update it if already exists |
| 265 | * @bat_priv: the bat priv with all the soft interface information |
| 266 | * @ip: ipv4 to add/edit |
| 267 | * @mac_addr: mac address to assign to the given ipv4 |
| 268 | */ |
| 269 | static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip, |
| 270 | uint8_t *mac_addr) |
| 271 | { |
| 272 | struct batadv_dat_entry *dat_entry; |
| 273 | int hash_added; |
| 274 | |
| 275 | dat_entry = batadv_dat_entry_hash_find(bat_priv, ip); |
| 276 | /* if this entry is already known, just update it */ |
| 277 | if (dat_entry) { |
| 278 | if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr)) |
| 279 | memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN); |
| 280 | dat_entry->last_update = jiffies; |
| 281 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 282 | "Entry updated: %pI4 %pM\n", &dat_entry->ip, |
| 283 | dat_entry->mac_addr); |
| 284 | goto out; |
| 285 | } |
| 286 | |
| 287 | dat_entry = kmalloc(sizeof(*dat_entry), GFP_ATOMIC); |
| 288 | if (!dat_entry) |
| 289 | goto out; |
| 290 | |
| 291 | dat_entry->ip = ip; |
| 292 | memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN); |
| 293 | dat_entry->last_update = jiffies; |
| 294 | atomic_set(&dat_entry->refcount, 2); |
| 295 | |
| 296 | hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat, |
| 297 | batadv_hash_dat, &dat_entry->ip, |
| 298 | &dat_entry->hash_entry); |
| 299 | |
| 300 | if (unlikely(hash_added != 0)) { |
| 301 | /* remove the reference for the hash */ |
| 302 | batadv_dat_entry_free_ref(dat_entry); |
| 303 | goto out; |
| 304 | } |
| 305 | |
| 306 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM\n", |
| 307 | &dat_entry->ip, dat_entry->mac_addr); |
| 308 | |
| 309 | out: |
| 310 | if (dat_entry) |
| 311 | batadv_dat_entry_free_ref(dat_entry); |
| 312 | } |
| 313 | |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 314 | #ifdef CONFIG_BATMAN_ADV_DEBUG |
| 315 | |
| 316 | /** |
| 317 | * batadv_dbg_arp - print a debug message containing all the ARP packet details |
| 318 | * @bat_priv: the bat priv with all the soft interface information |
| 319 | * @skb: ARP packet |
| 320 | * @type: ARP type |
| 321 | * @hdr_size: size of the possible header before the ARP packet |
| 322 | * @msg: message to print together with the debugging information |
| 323 | */ |
| 324 | static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb, |
| 325 | uint16_t type, int hdr_size, char *msg) |
| 326 | { |
| 327 | struct batadv_unicast_4addr_packet *unicast_4addr_packet; |
| 328 | struct batadv_bcast_packet *bcast_pkt; |
| 329 | uint8_t *orig_addr; |
| 330 | __be32 ip_src, ip_dst; |
| 331 | |
| 332 | if (msg) |
| 333 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "%s\n", msg); |
| 334 | |
| 335 | ip_src = batadv_arp_ip_src(skb, hdr_size); |
| 336 | ip_dst = batadv_arp_ip_dst(skb, hdr_size); |
| 337 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 338 | "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n", |
| 339 | batadv_arp_hw_src(skb, hdr_size), &ip_src, |
| 340 | batadv_arp_hw_dst(skb, hdr_size), &ip_dst); |
| 341 | |
| 342 | if (hdr_size == 0) |
| 343 | return; |
| 344 | |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 345 | unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; |
| 346 | |
| 347 | switch (unicast_4addr_packet->u.header.packet_type) { |
| 348 | case BATADV_UNICAST: |
| 349 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 350 | "* encapsulated within a UNICAST packet\n"); |
| 351 | break; |
| 352 | case BATADV_UNICAST_4ADDR: |
| 353 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 354 | "* encapsulated within a UNICAST_4ADDR packet (src: %pM)\n", |
| 355 | unicast_4addr_packet->src); |
| 356 | switch (unicast_4addr_packet->subtype) { |
| 357 | case BATADV_P_DAT_DHT_PUT: |
| 358 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_PUT\n"); |
| 359 | break; |
| 360 | case BATADV_P_DAT_DHT_GET: |
| 361 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_GET\n"); |
| 362 | break; |
| 363 | case BATADV_P_DAT_CACHE_REPLY: |
| 364 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 365 | "* type: DAT_CACHE_REPLY\n"); |
| 366 | break; |
| 367 | case BATADV_P_DATA: |
| 368 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DATA\n"); |
| 369 | break; |
| 370 | default: |
| 371 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: Unknown (%u)!\n", |
| 372 | unicast_4addr_packet->u.header.packet_type); |
| 373 | } |
| 374 | break; |
| 375 | case BATADV_BCAST: |
| 376 | bcast_pkt = (struct batadv_bcast_packet *)unicast_4addr_packet; |
| 377 | orig_addr = bcast_pkt->orig; |
| 378 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 379 | "* encapsulated within a BCAST packet (src: %pM)\n", |
| 380 | orig_addr); |
| 381 | break; |
| 382 | default: |
| 383 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 384 | "* encapsulated within an unknown packet type (0x%x)\n", |
| 385 | unicast_4addr_packet->u.header.packet_type); |
| 386 | } |
| 387 | } |
| 388 | |
| 389 | #else |
| 390 | |
| 391 | static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb, |
| 392 | uint16_t type, int hdr_size, char *msg) |
| 393 | { |
| 394 | } |
| 395 | |
| 396 | #endif /* CONFIG_BATMAN_ADV_DEBUG */ |
| 397 | |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 398 | /** |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 399 | * batadv_is_orig_node_eligible - check whether a node can be a DHT candidate |
| 400 | * @res: the array with the already selected candidates |
| 401 | * @select: number of already selected candidates |
| 402 | * @tmp_max: address of the currently evaluated node |
| 403 | * @max: current round max address |
| 404 | * @last_max: address of the last selected candidate |
| 405 | * @candidate: orig_node under evaluation |
| 406 | * @max_orig_node: last selected candidate |
| 407 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 408 | * Returns true if the node has been elected as next candidate or false |
| 409 | * otherwise. |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 410 | */ |
| 411 | static bool batadv_is_orig_node_eligible(struct batadv_dat_candidate *res, |
| 412 | int select, batadv_dat_addr_t tmp_max, |
| 413 | batadv_dat_addr_t max, |
| 414 | batadv_dat_addr_t last_max, |
| 415 | struct batadv_orig_node *candidate, |
| 416 | struct batadv_orig_node *max_orig_node) |
| 417 | { |
| 418 | bool ret = false; |
| 419 | int j; |
| 420 | |
Marek Lindner | 17cf0ea | 2013-04-23 21:39:59 +0800 | [diff] [blame] | 421 | /* check if orig node candidate is running DAT */ |
| 422 | if (!(candidate->capabilities & BATADV_ORIG_CAPA_HAS_DAT)) |
| 423 | goto out; |
| 424 | |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 425 | /* Check if this node has already been selected... */ |
| 426 | for (j = 0; j < select; j++) |
| 427 | if (res[j].orig_node == candidate) |
| 428 | break; |
| 429 | /* ..and possibly skip it */ |
| 430 | if (j < select) |
| 431 | goto out; |
| 432 | /* sanity check: has it already been selected? This should not happen */ |
| 433 | if (tmp_max > last_max) |
| 434 | goto out; |
| 435 | /* check if during this iteration an originator with a closer dht |
| 436 | * address has already been found |
| 437 | */ |
| 438 | if (tmp_max < max) |
| 439 | goto out; |
| 440 | /* this is an hash collision with the temporary selected node. Choose |
| 441 | * the one with the lowest address |
| 442 | */ |
Pau Koning | 816cd5b | 2013-02-12 00:18:45 +0000 | [diff] [blame] | 443 | if ((tmp_max == max) && max_orig_node && |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 444 | (batadv_compare_eth(candidate->orig, max_orig_node->orig) > 0)) |
| 445 | goto out; |
| 446 | |
| 447 | ret = true; |
| 448 | out: |
| 449 | return ret; |
| 450 | } |
| 451 | |
| 452 | /** |
| 453 | * batadv_choose_next_candidate - select the next DHT candidate |
| 454 | * @bat_priv: the bat priv with all the soft interface information |
| 455 | * @cands: candidates array |
| 456 | * @select: number of candidates already present in the array |
| 457 | * @ip_key: key to look up in the DHT |
| 458 | * @last_max: pointer where the address of the selected candidate will be saved |
| 459 | */ |
| 460 | static void batadv_choose_next_candidate(struct batadv_priv *bat_priv, |
| 461 | struct batadv_dat_candidate *cands, |
| 462 | int select, batadv_dat_addr_t ip_key, |
| 463 | batadv_dat_addr_t *last_max) |
| 464 | { |
| 465 | batadv_dat_addr_t max = 0, tmp_max = 0; |
| 466 | struct batadv_orig_node *orig_node, *max_orig_node = NULL; |
| 467 | struct batadv_hashtable *hash = bat_priv->orig_hash; |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 468 | struct hlist_head *head; |
| 469 | int i; |
| 470 | |
| 471 | /* if no node is eligible as candidate, leave the candidate type as |
| 472 | * NOT_FOUND |
| 473 | */ |
| 474 | cands[select].type = BATADV_DAT_CANDIDATE_NOT_FOUND; |
| 475 | |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 476 | /* iterate over the originator list and find the node with the closest |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 477 | * dat_address which has not been selected yet |
| 478 | */ |
| 479 | for (i = 0; i < hash->size; i++) { |
| 480 | head = &hash->table[i]; |
| 481 | |
| 482 | rcu_read_lock(); |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 483 | hlist_for_each_entry_rcu(orig_node, head, hash_entry) { |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 484 | /* the dht space is a ring using unsigned addresses */ |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 485 | tmp_max = BATADV_DAT_ADDR_MAX - orig_node->dat_addr + |
| 486 | ip_key; |
| 487 | |
| 488 | if (!batadv_is_orig_node_eligible(cands, select, |
| 489 | tmp_max, max, |
| 490 | *last_max, orig_node, |
| 491 | max_orig_node)) |
| 492 | continue; |
| 493 | |
| 494 | if (!atomic_inc_not_zero(&orig_node->refcount)) |
| 495 | continue; |
| 496 | |
| 497 | max = tmp_max; |
| 498 | if (max_orig_node) |
| 499 | batadv_orig_node_free_ref(max_orig_node); |
| 500 | max_orig_node = orig_node; |
| 501 | } |
| 502 | rcu_read_unlock(); |
| 503 | } |
| 504 | if (max_orig_node) { |
| 505 | cands[select].type = BATADV_DAT_CANDIDATE_ORIG; |
| 506 | cands[select].orig_node = max_orig_node; |
| 507 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 508 | "dat_select_candidates() %d: selected %pM addr=%u dist=%u\n", |
| 509 | select, max_orig_node->orig, max_orig_node->dat_addr, |
| 510 | max); |
| 511 | } |
| 512 | *last_max = max; |
| 513 | } |
| 514 | |
| 515 | /** |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 516 | * batadv_dat_select_candidates - select the nodes which the DHT message has to |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 517 | * be sent to |
| 518 | * @bat_priv: the bat priv with all the soft interface information |
| 519 | * @ip_dst: ipv4 to look up in the DHT |
| 520 | * |
| 521 | * An originator O is selected if and only if its DHT_ID value is one of three |
| 522 | * closest values (from the LEFT, with wrap around if needed) then the hash |
| 523 | * value of the key. ip_dst is the key. |
| 524 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 525 | * Returns the candidate array of size BATADV_DAT_CANDIDATE_NUM. |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 526 | */ |
| 527 | static struct batadv_dat_candidate * |
| 528 | batadv_dat_select_candidates(struct batadv_priv *bat_priv, __be32 ip_dst) |
| 529 | { |
| 530 | int select; |
| 531 | batadv_dat_addr_t last_max = BATADV_DAT_ADDR_MAX, ip_key; |
| 532 | struct batadv_dat_candidate *res; |
| 533 | |
| 534 | if (!bat_priv->orig_hash) |
| 535 | return NULL; |
| 536 | |
| 537 | res = kmalloc(BATADV_DAT_CANDIDATES_NUM * sizeof(*res), GFP_ATOMIC); |
| 538 | if (!res) |
| 539 | return NULL; |
| 540 | |
| 541 | ip_key = (batadv_dat_addr_t)batadv_hash_dat(&ip_dst, |
| 542 | BATADV_DAT_ADDR_MAX); |
| 543 | |
| 544 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 545 | "dat_select_candidates(): IP=%pI4 hash(IP)=%u\n", &ip_dst, |
| 546 | ip_key); |
| 547 | |
| 548 | for (select = 0; select < BATADV_DAT_CANDIDATES_NUM; select++) |
| 549 | batadv_choose_next_candidate(bat_priv, res, select, ip_key, |
| 550 | &last_max); |
| 551 | |
| 552 | return res; |
| 553 | } |
| 554 | |
| 555 | /** |
| 556 | * batadv_dat_send_data - send a payload to the selected candidates |
| 557 | * @bat_priv: the bat priv with all the soft interface information |
| 558 | * @skb: payload to send |
| 559 | * @ip: the DHT key |
| 560 | * @packet_subtype: unicast4addr packet subtype to use |
| 561 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 562 | * This function copies the skb with pskb_copy() and is sent as unicast packet |
| 563 | * to each of the selected candidates. |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 564 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 565 | * Returns true if the packet is sent to at least one candidate, false |
| 566 | * otherwise. |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 567 | */ |
| 568 | static bool batadv_dat_send_data(struct batadv_priv *bat_priv, |
| 569 | struct sk_buff *skb, __be32 ip, |
| 570 | int packet_subtype) |
| 571 | { |
| 572 | int i; |
| 573 | bool ret = false; |
| 574 | int send_status; |
| 575 | struct batadv_neigh_node *neigh_node = NULL; |
| 576 | struct sk_buff *tmp_skb; |
| 577 | struct batadv_dat_candidate *cand; |
| 578 | |
| 579 | cand = batadv_dat_select_candidates(bat_priv, ip); |
| 580 | if (!cand) |
| 581 | goto out; |
| 582 | |
| 583 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "DHT_SEND for %pI4\n", &ip); |
| 584 | |
| 585 | for (i = 0; i < BATADV_DAT_CANDIDATES_NUM; i++) { |
| 586 | if (cand[i].type == BATADV_DAT_CANDIDATE_NOT_FOUND) |
| 587 | continue; |
| 588 | |
| 589 | neigh_node = batadv_orig_node_get_router(cand[i].orig_node); |
| 590 | if (!neigh_node) |
| 591 | goto free_orig; |
| 592 | |
| 593 | tmp_skb = pskb_copy(skb, GFP_ATOMIC); |
Martin Hundebøll | f097e25 | 2013-05-23 16:53:01 +0200 | [diff] [blame^] | 594 | if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, tmp_skb, |
| 595 | cand[i].orig_node, |
| 596 | packet_subtype)) { |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 597 | kfree_skb(tmp_skb); |
| 598 | goto free_neigh; |
| 599 | } |
| 600 | |
| 601 | send_status = batadv_send_skb_packet(tmp_skb, |
| 602 | neigh_node->if_incoming, |
| 603 | neigh_node->addr); |
Martin Hundebøll | 4046b24 | 2012-04-20 17:02:45 +0200 | [diff] [blame] | 604 | if (send_status == NET_XMIT_SUCCESS) { |
| 605 | /* count the sent packet */ |
| 606 | switch (packet_subtype) { |
| 607 | case BATADV_P_DAT_DHT_GET: |
| 608 | batadv_inc_counter(bat_priv, |
| 609 | BATADV_CNT_DAT_GET_TX); |
| 610 | break; |
| 611 | case BATADV_P_DAT_DHT_PUT: |
| 612 | batadv_inc_counter(bat_priv, |
| 613 | BATADV_CNT_DAT_PUT_TX); |
| 614 | break; |
| 615 | } |
| 616 | |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 617 | /* packet sent to a candidate: return true */ |
| 618 | ret = true; |
Martin Hundebøll | 4046b24 | 2012-04-20 17:02:45 +0200 | [diff] [blame] | 619 | } |
Antonio Quartulli | 785ea11 | 2011-11-23 11:35:44 +0100 | [diff] [blame] | 620 | free_neigh: |
| 621 | batadv_neigh_node_free_ref(neigh_node); |
| 622 | free_orig: |
| 623 | batadv_orig_node_free_ref(cand[i].orig_node); |
| 624 | } |
| 625 | |
| 626 | out: |
| 627 | kfree(cand); |
| 628 | return ret; |
| 629 | } |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 630 | |
| 631 | /** |
Marek Lindner | 17cf0ea | 2013-04-23 21:39:59 +0800 | [diff] [blame] | 632 | * batadv_dat_tvlv_container_update - update the dat tvlv container after dat |
| 633 | * setting change |
| 634 | * @bat_priv: the bat priv with all the soft interface information |
| 635 | */ |
| 636 | static void batadv_dat_tvlv_container_update(struct batadv_priv *bat_priv) |
| 637 | { |
| 638 | char dat_mode; |
| 639 | |
| 640 | dat_mode = atomic_read(&bat_priv->distributed_arp_table); |
| 641 | |
| 642 | switch (dat_mode) { |
| 643 | case 0: |
| 644 | batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_DAT, 1); |
| 645 | break; |
| 646 | case 1: |
| 647 | batadv_tvlv_container_register(bat_priv, BATADV_TVLV_DAT, 1, |
| 648 | NULL, 0); |
| 649 | break; |
| 650 | } |
| 651 | } |
| 652 | |
| 653 | /** |
| 654 | * batadv_dat_status_update - update the dat tvlv container after dat |
| 655 | * setting change |
| 656 | * @net_dev: the soft interface net device |
| 657 | */ |
| 658 | void batadv_dat_status_update(struct net_device *net_dev) |
| 659 | { |
| 660 | struct batadv_priv *bat_priv = netdev_priv(net_dev); |
| 661 | batadv_dat_tvlv_container_update(bat_priv); |
| 662 | } |
| 663 | |
| 664 | /** |
| 665 | * batadv_gw_tvlv_ogm_handler_v1 - process incoming dat tvlv container |
| 666 | * @bat_priv: the bat priv with all the soft interface information |
| 667 | * @orig: the orig_node of the ogm |
| 668 | * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) |
| 669 | * @tvlv_value: tvlv buffer containing the gateway data |
| 670 | * @tvlv_value_len: tvlv buffer length |
| 671 | */ |
| 672 | static void batadv_dat_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, |
| 673 | struct batadv_orig_node *orig, |
| 674 | uint8_t flags, |
| 675 | void *tvlv_value, |
| 676 | uint16_t tvlv_value_len) |
| 677 | { |
| 678 | if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) |
| 679 | orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_DAT; |
| 680 | else |
| 681 | orig->capabilities |= BATADV_ORIG_CAPA_HAS_DAT; |
| 682 | } |
| 683 | |
| 684 | /** |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 685 | * batadv_dat_hash_free - free the local DAT hash table |
| 686 | * @bat_priv: the bat priv with all the soft interface information |
| 687 | */ |
| 688 | static void batadv_dat_hash_free(struct batadv_priv *bat_priv) |
| 689 | { |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 690 | if (!bat_priv->dat.hash) |
| 691 | return; |
| 692 | |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 693 | __batadv_dat_purge(bat_priv, NULL); |
| 694 | |
| 695 | batadv_hash_destroy(bat_priv->dat.hash); |
| 696 | |
| 697 | bat_priv->dat.hash = NULL; |
| 698 | } |
| 699 | |
| 700 | /** |
| 701 | * batadv_dat_init - initialise the DAT internals |
| 702 | * @bat_priv: the bat priv with all the soft interface information |
| 703 | */ |
| 704 | int batadv_dat_init(struct batadv_priv *bat_priv) |
| 705 | { |
| 706 | if (bat_priv->dat.hash) |
| 707 | return 0; |
| 708 | |
| 709 | bat_priv->dat.hash = batadv_hash_new(1024); |
| 710 | |
| 711 | if (!bat_priv->dat.hash) |
| 712 | return -ENOMEM; |
| 713 | |
| 714 | batadv_dat_start_timer(bat_priv); |
| 715 | |
Marek Lindner | 17cf0ea | 2013-04-23 21:39:59 +0800 | [diff] [blame] | 716 | batadv_tvlv_handler_register(bat_priv, batadv_dat_tvlv_ogm_handler_v1, |
| 717 | NULL, BATADV_TVLV_DAT, 1, |
| 718 | BATADV_TVLV_HANDLER_OGM_CIFNOTFND); |
| 719 | batadv_dat_tvlv_container_update(bat_priv); |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 720 | return 0; |
| 721 | } |
| 722 | |
| 723 | /** |
| 724 | * batadv_dat_free - free the DAT internals |
| 725 | * @bat_priv: the bat priv with all the soft interface information |
| 726 | */ |
| 727 | void batadv_dat_free(struct batadv_priv *bat_priv) |
| 728 | { |
Marek Lindner | 17cf0ea | 2013-04-23 21:39:59 +0800 | [diff] [blame] | 729 | batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_DAT, 1); |
| 730 | batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_DAT, 1); |
| 731 | |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 732 | cancel_delayed_work_sync(&bat_priv->dat.work); |
| 733 | |
| 734 | batadv_dat_hash_free(bat_priv); |
| 735 | } |
| 736 | |
| 737 | /** |
| 738 | * batadv_dat_cache_seq_print_text - print the local DAT hash table |
| 739 | * @seq: seq file to print on |
| 740 | * @offset: not used |
| 741 | */ |
| 742 | int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset) |
| 743 | { |
| 744 | struct net_device *net_dev = (struct net_device *)seq->private; |
| 745 | struct batadv_priv *bat_priv = netdev_priv(net_dev); |
| 746 | struct batadv_hashtable *hash = bat_priv->dat.hash; |
| 747 | struct batadv_dat_entry *dat_entry; |
| 748 | struct batadv_hard_iface *primary_if; |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 749 | struct hlist_head *head; |
| 750 | unsigned long last_seen_jiffies; |
| 751 | int last_seen_msecs, last_seen_secs, last_seen_mins; |
| 752 | uint32_t i; |
| 753 | |
| 754 | primary_if = batadv_seq_print_text_primary_if_get(seq); |
| 755 | if (!primary_if) |
| 756 | goto out; |
| 757 | |
| 758 | seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name); |
| 759 | seq_printf(seq, " %-7s %-13s %5s\n", "IPv4", "MAC", |
| 760 | "last-seen"); |
| 761 | |
| 762 | for (i = 0; i < hash->size; i++) { |
| 763 | head = &hash->table[i]; |
| 764 | |
| 765 | rcu_read_lock(); |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 766 | hlist_for_each_entry_rcu(dat_entry, head, hash_entry) { |
Antonio Quartulli | 2f1dfbe | 2012-06-30 20:01:19 +0200 | [diff] [blame] | 767 | last_seen_jiffies = jiffies - dat_entry->last_update; |
| 768 | last_seen_msecs = jiffies_to_msecs(last_seen_jiffies); |
| 769 | last_seen_mins = last_seen_msecs / 60000; |
| 770 | last_seen_msecs = last_seen_msecs % 60000; |
| 771 | last_seen_secs = last_seen_msecs / 1000; |
| 772 | |
| 773 | seq_printf(seq, " * %15pI4 %14pM %6i:%02i\n", |
| 774 | &dat_entry->ip, dat_entry->mac_addr, |
| 775 | last_seen_mins, last_seen_secs); |
| 776 | } |
| 777 | rcu_read_unlock(); |
| 778 | } |
| 779 | |
| 780 | out: |
| 781 | if (primary_if) |
| 782 | batadv_hardif_free_ref(primary_if); |
| 783 | return 0; |
| 784 | } |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 785 | |
| 786 | /** |
| 787 | * batadv_arp_get_type - parse an ARP packet and gets the type |
| 788 | * @bat_priv: the bat priv with all the soft interface information |
| 789 | * @skb: packet to analyse |
| 790 | * @hdr_size: size of the possible header before the ARP packet in the skb |
| 791 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 792 | * Returns the ARP type if the skb contains a valid ARP packet, 0 otherwise. |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 793 | */ |
| 794 | static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv, |
| 795 | struct sk_buff *skb, int hdr_size) |
| 796 | { |
| 797 | struct arphdr *arphdr; |
| 798 | struct ethhdr *ethhdr; |
| 799 | __be32 ip_src, ip_dst; |
Matthias Schiffer | b618ad1 | 2013-01-24 18:18:27 +0100 | [diff] [blame] | 800 | uint8_t *hw_src, *hw_dst; |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 801 | uint16_t type = 0; |
| 802 | |
| 803 | /* pull the ethernet header */ |
| 804 | if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN))) |
| 805 | goto out; |
| 806 | |
| 807 | ethhdr = (struct ethhdr *)(skb->data + hdr_size); |
| 808 | |
| 809 | if (ethhdr->h_proto != htons(ETH_P_ARP)) |
| 810 | goto out; |
| 811 | |
| 812 | /* pull the ARP payload */ |
| 813 | if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN + |
| 814 | arp_hdr_len(skb->dev)))) |
| 815 | goto out; |
| 816 | |
| 817 | arphdr = (struct arphdr *)(skb->data + hdr_size + ETH_HLEN); |
| 818 | |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 819 | /* check whether the ARP packet carries a valid IP information */ |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 820 | if (arphdr->ar_hrd != htons(ARPHRD_ETHER)) |
| 821 | goto out; |
| 822 | |
| 823 | if (arphdr->ar_pro != htons(ETH_P_IP)) |
| 824 | goto out; |
| 825 | |
| 826 | if (arphdr->ar_hln != ETH_ALEN) |
| 827 | goto out; |
| 828 | |
| 829 | if (arphdr->ar_pln != 4) |
| 830 | goto out; |
| 831 | |
| 832 | /* Check for bad reply/request. If the ARP message is not sane, DAT |
| 833 | * will simply ignore it |
| 834 | */ |
| 835 | ip_src = batadv_arp_ip_src(skb, hdr_size); |
| 836 | ip_dst = batadv_arp_ip_dst(skb, hdr_size); |
| 837 | if (ipv4_is_loopback(ip_src) || ipv4_is_multicast(ip_src) || |
Matthias Schiffer | 757dd82 | 2013-01-24 18:18:26 +0100 | [diff] [blame] | 838 | ipv4_is_loopback(ip_dst) || ipv4_is_multicast(ip_dst) || |
| 839 | ipv4_is_zeronet(ip_src) || ipv4_is_lbcast(ip_src) || |
| 840 | ipv4_is_zeronet(ip_dst) || ipv4_is_lbcast(ip_dst)) |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 841 | goto out; |
| 842 | |
Matthias Schiffer | b618ad1 | 2013-01-24 18:18:27 +0100 | [diff] [blame] | 843 | hw_src = batadv_arp_hw_src(skb, hdr_size); |
| 844 | if (is_zero_ether_addr(hw_src) || is_multicast_ether_addr(hw_src)) |
| 845 | goto out; |
| 846 | |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 847 | /* don't care about the destination MAC address in ARP requests */ |
Matthias Schiffer | b618ad1 | 2013-01-24 18:18:27 +0100 | [diff] [blame] | 848 | if (arphdr->ar_op != htons(ARPOP_REQUEST)) { |
| 849 | hw_dst = batadv_arp_hw_dst(skb, hdr_size); |
| 850 | if (is_zero_ether_addr(hw_dst) || |
| 851 | is_multicast_ether_addr(hw_dst)) |
| 852 | goto out; |
| 853 | } |
| 854 | |
Antonio Quartulli | 5c3a0e5 | 2011-06-02 12:29:51 +0200 | [diff] [blame] | 855 | type = ntohs(arphdr->ar_op); |
| 856 | out: |
| 857 | return type; |
| 858 | } |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 859 | |
| 860 | /** |
| 861 | * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to |
| 862 | * answer using DAT |
| 863 | * @bat_priv: the bat priv with all the soft interface information |
| 864 | * @skb: packet to check |
| 865 | * |
| 866 | * Returns true if the message has been sent to the dht candidates, false |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 867 | * otherwise. In case of a positive return value the message has to be enqueued |
| 868 | * to permit the fallback. |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 869 | */ |
| 870 | bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, |
| 871 | struct sk_buff *skb) |
| 872 | { |
| 873 | uint16_t type = 0; |
| 874 | __be32 ip_dst, ip_src; |
| 875 | uint8_t *hw_src; |
| 876 | bool ret = false; |
| 877 | struct batadv_dat_entry *dat_entry = NULL; |
| 878 | struct sk_buff *skb_new; |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 879 | |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 880 | if (!atomic_read(&bat_priv->distributed_arp_table)) |
| 881 | goto out; |
| 882 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 883 | type = batadv_arp_get_type(bat_priv, skb, 0); |
| 884 | /* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast |
| 885 | * message to the selected DHT candidates |
| 886 | */ |
| 887 | if (type != ARPOP_REQUEST) |
| 888 | goto out; |
| 889 | |
| 890 | batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REQUEST"); |
| 891 | |
| 892 | ip_src = batadv_arp_ip_src(skb, 0); |
| 893 | hw_src = batadv_arp_hw_src(skb, 0); |
| 894 | ip_dst = batadv_arp_ip_dst(skb, 0); |
| 895 | |
| 896 | batadv_dat_entry_add(bat_priv, ip_src, hw_src); |
| 897 | |
| 898 | dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); |
| 899 | if (dat_entry) { |
Antonio Quartulli | 88e48d7 | 2013-05-09 09:35:45 +0200 | [diff] [blame] | 900 | /* If the ARP request is destined for a local client the local |
| 901 | * client will answer itself. DAT would only generate a |
| 902 | * duplicate packet. |
| 903 | * |
| 904 | * Moreover, if the soft-interface is enslaved into a bridge, an |
| 905 | * additional DAT answer may trigger kernel warnings about |
| 906 | * a packet coming from the wrong port. |
| 907 | */ |
| 908 | if (batadv_is_my_client(bat_priv, dat_entry->mac_addr)) { |
| 909 | ret = true; |
| 910 | goto out; |
| 911 | } |
| 912 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 913 | skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src, |
Marek Lindner | 736292c | 2013-01-12 19:19:06 +0800 | [diff] [blame] | 914 | bat_priv->soft_iface, ip_dst, hw_src, |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 915 | dat_entry->mac_addr, hw_src); |
| 916 | if (!skb_new) |
| 917 | goto out; |
| 918 | |
| 919 | skb_reset_mac_header(skb_new); |
| 920 | skb_new->protocol = eth_type_trans(skb_new, |
Marek Lindner | 736292c | 2013-01-12 19:19:06 +0800 | [diff] [blame] | 921 | bat_priv->soft_iface); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 922 | bat_priv->stats.rx_packets++; |
| 923 | bat_priv->stats.rx_bytes += skb->len + ETH_HLEN; |
Marek Lindner | 736292c | 2013-01-12 19:19:06 +0800 | [diff] [blame] | 924 | bat_priv->soft_iface->last_rx = jiffies; |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 925 | |
| 926 | netif_rx(skb_new); |
| 927 | batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n"); |
| 928 | ret = true; |
| 929 | } else { |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 930 | /* Send the request to the DHT */ |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 931 | ret = batadv_dat_send_data(bat_priv, skb, ip_dst, |
| 932 | BATADV_P_DAT_DHT_GET); |
| 933 | } |
| 934 | out: |
| 935 | if (dat_entry) |
| 936 | batadv_dat_entry_free_ref(dat_entry); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 937 | return ret; |
| 938 | } |
| 939 | |
| 940 | /** |
| 941 | * batadv_dat_snoop_incoming_arp_request - snoop the ARP request and try to |
| 942 | * answer using the local DAT storage |
| 943 | * @bat_priv: the bat priv with all the soft interface information |
| 944 | * @skb: packet to check |
| 945 | * @hdr_size: size of the encapsulation header |
| 946 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 947 | * Returns true if the request has been answered, false otherwise. |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 948 | */ |
| 949 | bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, |
| 950 | struct sk_buff *skb, int hdr_size) |
| 951 | { |
| 952 | uint16_t type; |
| 953 | __be32 ip_src, ip_dst; |
| 954 | uint8_t *hw_src; |
| 955 | struct sk_buff *skb_new; |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 956 | struct batadv_dat_entry *dat_entry = NULL; |
| 957 | bool ret = false; |
| 958 | int err; |
| 959 | |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 960 | if (!atomic_read(&bat_priv->distributed_arp_table)) |
| 961 | goto out; |
| 962 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 963 | type = batadv_arp_get_type(bat_priv, skb, hdr_size); |
| 964 | if (type != ARPOP_REQUEST) |
| 965 | goto out; |
| 966 | |
| 967 | hw_src = batadv_arp_hw_src(skb, hdr_size); |
| 968 | ip_src = batadv_arp_ip_src(skb, hdr_size); |
| 969 | ip_dst = batadv_arp_ip_dst(skb, hdr_size); |
| 970 | |
| 971 | batadv_dbg_arp(bat_priv, skb, type, hdr_size, |
| 972 | "Parsing incoming ARP REQUEST"); |
| 973 | |
| 974 | batadv_dat_entry_add(bat_priv, ip_src, hw_src); |
| 975 | |
| 976 | dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); |
| 977 | if (!dat_entry) |
| 978 | goto out; |
| 979 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 980 | skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src, |
Marek Lindner | 736292c | 2013-01-12 19:19:06 +0800 | [diff] [blame] | 981 | bat_priv->soft_iface, ip_dst, hw_src, |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 982 | dat_entry->mac_addr, hw_src); |
| 983 | |
| 984 | if (!skb_new) |
| 985 | goto out; |
| 986 | |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 987 | /* To preserve backwards compatibility, the node has choose the outgoing |
| 988 | * format based on the incoming request packet type. The assumption is |
| 989 | * that a node not using the 4addr packet format doesn't support it. |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 990 | */ |
| 991 | if (hdr_size == sizeof(struct batadv_unicast_4addr_packet)) |
Martin Hundebøll | f097e25 | 2013-05-23 16:53:01 +0200 | [diff] [blame^] | 992 | err = batadv_send_skb_unicast_4addr(bat_priv, skb_new, |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 993 | BATADV_P_DAT_CACHE_REPLY); |
| 994 | else |
Martin Hundebøll | f097e25 | 2013-05-23 16:53:01 +0200 | [diff] [blame^] | 995 | err = batadv_send_skb_unicast(bat_priv, skb_new); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 996 | |
Martin Hundebøll | 4046b24 | 2012-04-20 17:02:45 +0200 | [diff] [blame] | 997 | if (!err) { |
| 998 | batadv_inc_counter(bat_priv, BATADV_CNT_DAT_CACHED_REPLY_TX); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 999 | ret = true; |
Martin Hundebøll | 4046b24 | 2012-04-20 17:02:45 +0200 | [diff] [blame] | 1000 | } |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1001 | out: |
| 1002 | if (dat_entry) |
| 1003 | batadv_dat_entry_free_ref(dat_entry); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1004 | if (ret) |
| 1005 | kfree_skb(skb); |
| 1006 | return ret; |
| 1007 | } |
| 1008 | |
| 1009 | /** |
| 1010 | * batadv_dat_snoop_outgoing_arp_reply - snoop the ARP reply and fill the DHT |
| 1011 | * @bat_priv: the bat priv with all the soft interface information |
| 1012 | * @skb: packet to check |
| 1013 | */ |
| 1014 | void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv, |
| 1015 | struct sk_buff *skb) |
| 1016 | { |
| 1017 | uint16_t type; |
| 1018 | __be32 ip_src, ip_dst; |
| 1019 | uint8_t *hw_src, *hw_dst; |
| 1020 | |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 1021 | if (!atomic_read(&bat_priv->distributed_arp_table)) |
| 1022 | return; |
| 1023 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1024 | type = batadv_arp_get_type(bat_priv, skb, 0); |
| 1025 | if (type != ARPOP_REPLY) |
| 1026 | return; |
| 1027 | |
| 1028 | batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REPLY"); |
| 1029 | |
| 1030 | hw_src = batadv_arp_hw_src(skb, 0); |
| 1031 | ip_src = batadv_arp_ip_src(skb, 0); |
| 1032 | hw_dst = batadv_arp_hw_dst(skb, 0); |
| 1033 | ip_dst = batadv_arp_ip_dst(skb, 0); |
| 1034 | |
| 1035 | batadv_dat_entry_add(bat_priv, ip_src, hw_src); |
| 1036 | batadv_dat_entry_add(bat_priv, ip_dst, hw_dst); |
| 1037 | |
| 1038 | /* Send the ARP reply to the candidates for both the IP addresses that |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 1039 | * the node obtained from the ARP reply |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1040 | */ |
| 1041 | batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT); |
| 1042 | batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT); |
| 1043 | } |
| 1044 | /** |
| 1045 | * batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local |
| 1046 | * DAT storage only |
| 1047 | * @bat_priv: the bat priv with all the soft interface information |
| 1048 | * @skb: packet to check |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 1049 | * @hdr_size: size of the encapsulation header |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1050 | */ |
| 1051 | bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, |
| 1052 | struct sk_buff *skb, int hdr_size) |
| 1053 | { |
| 1054 | uint16_t type; |
| 1055 | __be32 ip_src, ip_dst; |
| 1056 | uint8_t *hw_src, *hw_dst; |
| 1057 | bool ret = false; |
| 1058 | |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 1059 | if (!atomic_read(&bat_priv->distributed_arp_table)) |
| 1060 | goto out; |
| 1061 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1062 | type = batadv_arp_get_type(bat_priv, skb, hdr_size); |
| 1063 | if (type != ARPOP_REPLY) |
| 1064 | goto out; |
| 1065 | |
| 1066 | batadv_dbg_arp(bat_priv, skb, type, hdr_size, |
| 1067 | "Parsing incoming ARP REPLY"); |
| 1068 | |
| 1069 | hw_src = batadv_arp_hw_src(skb, hdr_size); |
| 1070 | ip_src = batadv_arp_ip_src(skb, hdr_size); |
| 1071 | hw_dst = batadv_arp_hw_dst(skb, hdr_size); |
| 1072 | ip_dst = batadv_arp_ip_dst(skb, hdr_size); |
| 1073 | |
| 1074 | /* Update our internal cache with both the IP addresses the node got |
| 1075 | * within the ARP reply |
| 1076 | */ |
| 1077 | batadv_dat_entry_add(bat_priv, ip_src, hw_src); |
| 1078 | batadv_dat_entry_add(bat_priv, ip_dst, hw_dst); |
| 1079 | |
| 1080 | /* if this REPLY is directed to a client of mine, let's deliver the |
| 1081 | * packet to the interface |
| 1082 | */ |
| 1083 | ret = !batadv_is_my_client(bat_priv, hw_dst); |
| 1084 | out: |
Matthias Schiffer | 0d15bec | 2013-01-23 18:11:53 +0100 | [diff] [blame] | 1085 | if (ret) |
| 1086 | kfree_skb(skb); |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1087 | /* if ret == false -> packet has to be delivered to the interface */ |
| 1088 | return ret; |
| 1089 | } |
| 1090 | |
| 1091 | /** |
| 1092 | * batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 1093 | * (because the node has already obtained the reply via DAT) or not |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1094 | * @bat_priv: the bat priv with all the soft interface information |
| 1095 | * @forw_packet: the broadcast packet |
| 1096 | * |
Marek Lindner | 9317801 | 2013-03-10 19:29:15 +0800 | [diff] [blame] | 1097 | * Returns true if the node can drop the packet, false otherwise. |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1098 | */ |
| 1099 | bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv, |
| 1100 | struct batadv_forw_packet *forw_packet) |
| 1101 | { |
| 1102 | uint16_t type; |
| 1103 | __be32 ip_dst; |
| 1104 | struct batadv_dat_entry *dat_entry = NULL; |
| 1105 | bool ret = false; |
| 1106 | const size_t bcast_len = sizeof(struct batadv_bcast_packet); |
| 1107 | |
Antonio Quartulli | 33af49a | 2012-08-08 18:50:57 +0200 | [diff] [blame] | 1108 | if (!atomic_read(&bat_priv->distributed_arp_table)) |
| 1109 | goto out; |
| 1110 | |
Antonio Quartulli | c384ea3 | 2011-06-26 03:37:18 +0200 | [diff] [blame] | 1111 | /* If this packet is an ARP_REQUEST and the node already has the |
| 1112 | * information that it is going to ask, then the packet can be dropped |
| 1113 | */ |
| 1114 | if (forw_packet->num_packets) |
| 1115 | goto out; |
| 1116 | |
| 1117 | type = batadv_arp_get_type(bat_priv, forw_packet->skb, bcast_len); |
| 1118 | if (type != ARPOP_REQUEST) |
| 1119 | goto out; |
| 1120 | |
| 1121 | ip_dst = batadv_arp_ip_dst(forw_packet->skb, bcast_len); |
| 1122 | dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); |
| 1123 | /* check if the node already got this entry */ |
| 1124 | if (!dat_entry) { |
| 1125 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 1126 | "ARP Request for %pI4: fallback\n", &ip_dst); |
| 1127 | goto out; |
| 1128 | } |
| 1129 | |
| 1130 | batadv_dbg(BATADV_DBG_DAT, bat_priv, |
| 1131 | "ARP Request for %pI4: fallback prevented\n", &ip_dst); |
| 1132 | ret = true; |
| 1133 | |
| 1134 | out: |
| 1135 | if (dat_entry) |
| 1136 | batadv_dat_entry_free_ref(dat_entry); |
| 1137 | return ret; |
| 1138 | } |