1 /* Copyright (C) 2007-2012 B.A.T.M.A.N. contributors: 2 * 3 * Marek Lindner, Simon Wunderlich 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 "main.h" 21 #include "distributed-arp-table.h" 22 #include "send.h" 23 #include "routing.h" 24 #include "translation-table.h" 25 #include "soft-interface.h" 26 #include "hard-interface.h" 27 #include "vis.h" 28 #include "gateway_common.h" 29 #include "originator.h" 30 31 #include <linux/if_ether.h> 32 33 static void batadv_send_outstanding_bcast_packet(struct work_struct *work); 34 35 /* send out an already prepared packet to the given address via the 36 * specified batman interface 37 */ 38 int batadv_send_skb_packet(struct sk_buff *skb, 39 struct batadv_hard_iface *hard_iface, 40 const uint8_t *dst_addr) 41 { 42 struct ethhdr *ethhdr; 43 44 if (hard_iface->if_status != BATADV_IF_ACTIVE) 45 goto send_skb_err; 46 47 if (unlikely(!hard_iface->net_dev)) 48 goto send_skb_err; 49 50 if (!(hard_iface->net_dev->flags & IFF_UP)) { 51 pr_warn("Interface %s is not up - can't send packet via that interface!\n", 52 hard_iface->net_dev->name); 53 goto send_skb_err; 54 } 55 56 /* push to the ethernet header. */ 57 if (batadv_skb_head_push(skb, ETH_HLEN) < 0) 58 goto send_skb_err; 59 60 skb_reset_mac_header(skb); 61 62 ethhdr = (struct ethhdr *)skb_mac_header(skb); 63 memcpy(ethhdr->h_source, hard_iface->net_dev->dev_addr, ETH_ALEN); 64 memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN); 65 ethhdr->h_proto = __constant_htons(ETH_P_BATMAN); 66 67 skb_set_network_header(skb, ETH_HLEN); 68 skb->priority = TC_PRIO_CONTROL; 69 skb->protocol = __constant_htons(ETH_P_BATMAN); 70 71 skb->dev = hard_iface->net_dev; 72 73 /* dev_queue_xmit() returns a negative result on error. However on 74 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP 75 * (which is > 0). This will not be treated as an error. 76 */ 77 return dev_queue_xmit(skb); 78 send_skb_err: 79 kfree_skb(skb); 80 return NET_XMIT_DROP; 81 } 82 83 /** 84 * batadv_send_skb_to_orig - Lookup next-hop and transmit skb. 85 * @skb: Packet to be transmitted. 86 * @orig_node: Final destination of the packet. 87 * @recv_if: Interface used when receiving the packet (can be NULL). 88 * 89 * Looks up the best next-hop towards the passed originator and passes the 90 * skb on for preparation of MAC header. If the packet originated from this 91 * host, NULL can be passed as recv_if and no interface alternating is 92 * attempted. 93 * 94 * Returns TRUE on success; FALSE otherwise. 95 */ 96 bool batadv_send_skb_to_orig(struct sk_buff *skb, 97 struct batadv_orig_node *orig_node, 98 struct batadv_hard_iface *recv_if) 99 { 100 struct batadv_priv *bat_priv = orig_node->bat_priv; 101 struct batadv_neigh_node *neigh_node; 102 103 /* batadv_find_router() increases neigh_nodes refcount if found. */ 104 neigh_node = batadv_find_router(bat_priv, orig_node, recv_if); 105 if (!neigh_node) 106 return false; 107 108 /* route it */ 109 batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); 110 111 batadv_neigh_node_free_ref(neigh_node); 112 113 return true; 114 } 115 116 void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface) 117 { 118 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 119 120 if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) || 121 (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)) 122 return; 123 124 /* the interface gets activated here to avoid race conditions between 125 * the moment of activating the interface in 126 * hardif_activate_interface() where the originator mac is set and 127 * outdated packets (especially uninitialized mac addresses) in the 128 * packet queue 129 */ 130 if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED) 131 hard_iface->if_status = BATADV_IF_ACTIVE; 132 133 bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface); 134 } 135 136 static void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet) 137 { 138 if (forw_packet->skb) 139 kfree_skb(forw_packet->skb); 140 if (forw_packet->if_incoming) 141 batadv_hardif_free_ref(forw_packet->if_incoming); 142 kfree(forw_packet); 143 } 144 145 static void 146 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, 147 struct batadv_forw_packet *forw_packet, 148 unsigned long send_time) 149 { 150 INIT_HLIST_NODE(&forw_packet->list); 151 152 /* add new packet to packet list */ 153 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 154 hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list); 155 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 156 157 /* start timer for this packet */ 158 INIT_DELAYED_WORK(&forw_packet->delayed_work, 159 batadv_send_outstanding_bcast_packet); 160 queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work, 161 send_time); 162 } 163 164 /* add a broadcast packet to the queue and setup timers. broadcast packets 165 * are sent multiple times to increase probability for being received. 166 * 167 * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on 168 * errors. 169 * 170 * The skb is not consumed, so the caller should make sure that the 171 * skb is freed. 172 */ 173 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, 174 const struct sk_buff *skb, 175 unsigned long delay) 176 { 177 struct batadv_hard_iface *primary_if = NULL; 178 struct batadv_forw_packet *forw_packet; 179 struct batadv_bcast_packet *bcast_packet; 180 struct sk_buff *newskb; 181 182 if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) { 183 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 184 "bcast packet queue full\n"); 185 goto out; 186 } 187 188 primary_if = batadv_primary_if_get_selected(bat_priv); 189 if (!primary_if) 190 goto out_and_inc; 191 192 forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC); 193 194 if (!forw_packet) 195 goto out_and_inc; 196 197 newskb = skb_copy(skb, GFP_ATOMIC); 198 if (!newskb) 199 goto packet_free; 200 201 /* as we have a copy now, it is safe to decrease the TTL */ 202 bcast_packet = (struct batadv_bcast_packet *)newskb->data; 203 bcast_packet->header.ttl--; 204 205 skb_reset_mac_header(newskb); 206 207 forw_packet->skb = newskb; 208 forw_packet->if_incoming = primary_if; 209 210 /* how often did we send the bcast packet ? */ 211 forw_packet->num_packets = 0; 212 213 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay); 214 return NETDEV_TX_OK; 215 216 packet_free: 217 kfree(forw_packet); 218 out_and_inc: 219 atomic_inc(&bat_priv->bcast_queue_left); 220 out: 221 if (primary_if) 222 batadv_hardif_free_ref(primary_if); 223 return NETDEV_TX_BUSY; 224 } 225 226 static void batadv_send_outstanding_bcast_packet(struct work_struct *work) 227 { 228 struct batadv_hard_iface *hard_iface; 229 struct delayed_work *delayed_work; 230 struct batadv_forw_packet *forw_packet; 231 struct sk_buff *skb1; 232 struct net_device *soft_iface; 233 struct batadv_priv *bat_priv; 234 235 delayed_work = container_of(work, struct delayed_work, work); 236 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 237 delayed_work); 238 soft_iface = forw_packet->if_incoming->soft_iface; 239 bat_priv = netdev_priv(soft_iface); 240 241 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 242 hlist_del(&forw_packet->list); 243 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 244 245 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 246 goto out; 247 248 if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) 249 goto out; 250 251 /* rebroadcast packet */ 252 rcu_read_lock(); 253 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 254 if (hard_iface->soft_iface != soft_iface) 255 continue; 256 257 /* send a copy of the saved skb */ 258 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC); 259 if (skb1) 260 batadv_send_skb_packet(skb1, hard_iface, 261 batadv_broadcast_addr); 262 } 263 rcu_read_unlock(); 264 265 forw_packet->num_packets++; 266 267 /* if we still have some more bcasts to send */ 268 if (forw_packet->num_packets < 3) { 269 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, 270 msecs_to_jiffies(5)); 271 return; 272 } 273 274 out: 275 batadv_forw_packet_free(forw_packet); 276 atomic_inc(&bat_priv->bcast_queue_left); 277 } 278 279 void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work) 280 { 281 struct delayed_work *delayed_work; 282 struct batadv_forw_packet *forw_packet; 283 struct batadv_priv *bat_priv; 284 285 delayed_work = container_of(work, struct delayed_work, work); 286 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 287 delayed_work); 288 bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface); 289 spin_lock_bh(&bat_priv->forw_bat_list_lock); 290 hlist_del(&forw_packet->list); 291 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 292 293 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 294 goto out; 295 296 bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet); 297 298 /* we have to have at least one packet in the queue 299 * to determine the queues wake up time unless we are 300 * shutting down 301 */ 302 if (forw_packet->own) 303 batadv_schedule_bat_ogm(forw_packet->if_incoming); 304 305 out: 306 /* don't count own packet */ 307 if (!forw_packet->own) 308 atomic_inc(&bat_priv->batman_queue_left); 309 310 batadv_forw_packet_free(forw_packet); 311 } 312 313 void 314 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv, 315 const struct batadv_hard_iface *hard_iface) 316 { 317 struct batadv_forw_packet *forw_packet; 318 struct hlist_node *tmp_node, *safe_tmp_node; 319 bool pending; 320 321 if (hard_iface) 322 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 323 "purge_outstanding_packets(): %s\n", 324 hard_iface->net_dev->name); 325 else 326 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 327 "purge_outstanding_packets()\n"); 328 329 /* free bcast list */ 330 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 331 hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node, 332 &bat_priv->forw_bcast_list, list) { 333 334 /* if purge_outstanding_packets() was called with an argument 335 * we delete only packets belonging to the given interface 336 */ 337 if ((hard_iface) && 338 (forw_packet->if_incoming != hard_iface)) 339 continue; 340 341 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 342 343 /* batadv_send_outstanding_bcast_packet() will lock the list to 344 * delete the item from the list 345 */ 346 pending = cancel_delayed_work_sync(&forw_packet->delayed_work); 347 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 348 349 if (pending) { 350 hlist_del(&forw_packet->list); 351 batadv_forw_packet_free(forw_packet); 352 } 353 } 354 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 355 356 /* free batman packet list */ 357 spin_lock_bh(&bat_priv->forw_bat_list_lock); 358 hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node, 359 &bat_priv->forw_bat_list, list) { 360 361 /* if purge_outstanding_packets() was called with an argument 362 * we delete only packets belonging to the given interface 363 */ 364 if ((hard_iface) && 365 (forw_packet->if_incoming != hard_iface)) 366 continue; 367 368 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 369 370 /* send_outstanding_bat_packet() will lock the list to 371 * delete the item from the list 372 */ 373 pending = cancel_delayed_work_sync(&forw_packet->delayed_work); 374 spin_lock_bh(&bat_priv->forw_bat_list_lock); 375 376 if (pending) { 377 hlist_del(&forw_packet->list); 378 batadv_forw_packet_free(forw_packet); 379 } 380 } 381 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 382 } 383