1 /* Copyright (C) 2007-2013 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 queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work, 159 send_time); 160 } 161 162 /* add a broadcast packet to the queue and setup timers. broadcast packets 163 * are sent multiple times to increase probability for being received. 164 * 165 * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on 166 * errors. 167 * 168 * The skb is not consumed, so the caller should make sure that the 169 * skb is freed. 170 */ 171 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, 172 const struct sk_buff *skb, 173 unsigned long delay) 174 { 175 struct batadv_hard_iface *primary_if = NULL; 176 struct batadv_forw_packet *forw_packet; 177 struct batadv_bcast_packet *bcast_packet; 178 struct sk_buff *newskb; 179 180 if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) { 181 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 182 "bcast packet queue full\n"); 183 goto out; 184 } 185 186 primary_if = batadv_primary_if_get_selected(bat_priv); 187 if (!primary_if) 188 goto out_and_inc; 189 190 forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC); 191 192 if (!forw_packet) 193 goto out_and_inc; 194 195 newskb = skb_copy(skb, GFP_ATOMIC); 196 if (!newskb) 197 goto packet_free; 198 199 /* as we have a copy now, it is safe to decrease the TTL */ 200 bcast_packet = (struct batadv_bcast_packet *)newskb->data; 201 bcast_packet->header.ttl--; 202 203 skb_reset_mac_header(newskb); 204 205 forw_packet->skb = newskb; 206 forw_packet->if_incoming = primary_if; 207 208 /* how often did we send the bcast packet ? */ 209 forw_packet->num_packets = 0; 210 211 INIT_DELAYED_WORK(&forw_packet->delayed_work, 212 batadv_send_outstanding_bcast_packet); 213 214 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay); 215 return NETDEV_TX_OK; 216 217 packet_free: 218 kfree(forw_packet); 219 out_and_inc: 220 atomic_inc(&bat_priv->bcast_queue_left); 221 out: 222 if (primary_if) 223 batadv_hardif_free_ref(primary_if); 224 return NETDEV_TX_BUSY; 225 } 226 227 static void batadv_send_outstanding_bcast_packet(struct work_struct *work) 228 { 229 struct batadv_hard_iface *hard_iface; 230 struct delayed_work *delayed_work; 231 struct batadv_forw_packet *forw_packet; 232 struct sk_buff *skb1; 233 struct net_device *soft_iface; 234 struct batadv_priv *bat_priv; 235 236 delayed_work = container_of(work, struct delayed_work, work); 237 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 238 delayed_work); 239 soft_iface = forw_packet->if_incoming->soft_iface; 240 bat_priv = netdev_priv(soft_iface); 241 242 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 243 hlist_del(&forw_packet->list); 244 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 245 246 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 247 goto out; 248 249 if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) 250 goto out; 251 252 /* rebroadcast packet */ 253 rcu_read_lock(); 254 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 255 if (hard_iface->soft_iface != soft_iface) 256 continue; 257 258 /* send a copy of the saved skb */ 259 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC); 260 if (skb1) 261 batadv_send_skb_packet(skb1, hard_iface, 262 batadv_broadcast_addr); 263 } 264 rcu_read_unlock(); 265 266 forw_packet->num_packets++; 267 268 /* if we still have some more bcasts to send */ 269 if (forw_packet->num_packets < 3) { 270 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, 271 msecs_to_jiffies(5)); 272 return; 273 } 274 275 out: 276 batadv_forw_packet_free(forw_packet); 277 atomic_inc(&bat_priv->bcast_queue_left); 278 } 279 280 void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work) 281 { 282 struct delayed_work *delayed_work; 283 struct batadv_forw_packet *forw_packet; 284 struct batadv_priv *bat_priv; 285 286 delayed_work = container_of(work, struct delayed_work, work); 287 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 288 delayed_work); 289 bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface); 290 spin_lock_bh(&bat_priv->forw_bat_list_lock); 291 hlist_del(&forw_packet->list); 292 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 293 294 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 295 goto out; 296 297 bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet); 298 299 /* we have to have at least one packet in the queue 300 * to determine the queues wake up time unless we are 301 * shutting down 302 */ 303 if (forw_packet->own) 304 batadv_schedule_bat_ogm(forw_packet->if_incoming); 305 306 out: 307 /* don't count own packet */ 308 if (!forw_packet->own) 309 atomic_inc(&bat_priv->batman_queue_left); 310 311 batadv_forw_packet_free(forw_packet); 312 } 313 314 void 315 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv, 316 const struct batadv_hard_iface *hard_iface) 317 { 318 struct batadv_forw_packet *forw_packet; 319 struct hlist_node *tmp_node, *safe_tmp_node; 320 bool pending; 321 322 if (hard_iface) 323 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 324 "purge_outstanding_packets(): %s\n", 325 hard_iface->net_dev->name); 326 else 327 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 328 "purge_outstanding_packets()\n"); 329 330 /* free bcast list */ 331 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 332 hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node, 333 &bat_priv->forw_bcast_list, list) { 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 /* if purge_outstanding_packets() was called with an argument 361 * we delete only packets belonging to the given interface 362 */ 363 if ((hard_iface) && 364 (forw_packet->if_incoming != hard_iface)) 365 continue; 366 367 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 368 369 /* send_outstanding_bat_packet() will lock the list to 370 * delete the item from the list 371 */ 372 pending = cancel_delayed_work_sync(&forw_packet->delayed_work); 373 spin_lock_bh(&bat_priv->forw_bat_list_lock); 374 375 if (pending) { 376 hlist_del(&forw_packet->list); 377 batadv_forw_packet_free(forw_packet); 378 } 379 } 380 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 381 } 382