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 #include "network-coding.h" 31 32 #include <linux/if_ether.h> 33 34 static void batadv_send_outstanding_bcast_packet(struct work_struct *work); 35 36 /* send out an already prepared packet to the given address via the 37 * specified batman interface 38 */ 39 int batadv_send_skb_packet(struct sk_buff *skb, 40 struct batadv_hard_iface *hard_iface, 41 const uint8_t *dst_addr) 42 { 43 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 44 struct ethhdr *ethhdr; 45 46 if (hard_iface->if_status != BATADV_IF_ACTIVE) 47 goto send_skb_err; 48 49 if (unlikely(!hard_iface->net_dev)) 50 goto send_skb_err; 51 52 if (!(hard_iface->net_dev->flags & IFF_UP)) { 53 pr_warn("Interface %s is not up - can't send packet via that interface!\n", 54 hard_iface->net_dev->name); 55 goto send_skb_err; 56 } 57 58 /* push to the ethernet header. */ 59 if (batadv_skb_head_push(skb, ETH_HLEN) < 0) 60 goto send_skb_err; 61 62 skb_reset_mac_header(skb); 63 64 ethhdr = (struct ethhdr *)skb_mac_header(skb); 65 memcpy(ethhdr->h_source, hard_iface->net_dev->dev_addr, ETH_ALEN); 66 memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN); 67 ethhdr->h_proto = __constant_htons(ETH_P_BATMAN); 68 69 skb_set_network_header(skb, ETH_HLEN); 70 skb->priority = TC_PRIO_CONTROL; 71 skb->protocol = __constant_htons(ETH_P_BATMAN); 72 73 skb->dev = hard_iface->net_dev; 74 75 /* Save a clone of the skb to use when decoding coded packets */ 76 batadv_nc_skb_store_for_decoding(bat_priv, skb); 77 78 /* dev_queue_xmit() returns a negative result on error. However on 79 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP 80 * (which is > 0). This will not be treated as an error. 81 */ 82 return dev_queue_xmit(skb); 83 send_skb_err: 84 kfree_skb(skb); 85 return NET_XMIT_DROP; 86 } 87 88 /** 89 * batadv_send_skb_to_orig - Lookup next-hop and transmit skb. 90 * @skb: Packet to be transmitted. 91 * @orig_node: Final destination of the packet. 92 * @recv_if: Interface used when receiving the packet (can be NULL). 93 * 94 * Looks up the best next-hop towards the passed originator and passes the 95 * skb on for preparation of MAC header. If the packet originated from this 96 * host, NULL can be passed as recv_if and no interface alternating is 97 * attempted. 98 * 99 * Returns TRUE on success; FALSE otherwise. 100 */ 101 bool batadv_send_skb_to_orig(struct sk_buff *skb, 102 struct batadv_orig_node *orig_node, 103 struct batadv_hard_iface *recv_if) 104 { 105 struct batadv_priv *bat_priv = orig_node->bat_priv; 106 struct batadv_neigh_node *neigh_node; 107 108 /* batadv_find_router() increases neigh_nodes refcount if found. */ 109 neigh_node = batadv_find_router(bat_priv, orig_node, recv_if); 110 if (!neigh_node) 111 return false; 112 113 /* route it */ 114 batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); 115 116 batadv_neigh_node_free_ref(neigh_node); 117 118 return true; 119 } 120 121 void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface) 122 { 123 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 124 125 if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) || 126 (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)) 127 return; 128 129 /* the interface gets activated here to avoid race conditions between 130 * the moment of activating the interface in 131 * hardif_activate_interface() where the originator mac is set and 132 * outdated packets (especially uninitialized mac addresses) in the 133 * packet queue 134 */ 135 if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED) 136 hard_iface->if_status = BATADV_IF_ACTIVE; 137 138 bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface); 139 } 140 141 static void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet) 142 { 143 if (forw_packet->skb) 144 kfree_skb(forw_packet->skb); 145 if (forw_packet->if_incoming) 146 batadv_hardif_free_ref(forw_packet->if_incoming); 147 kfree(forw_packet); 148 } 149 150 static void 151 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, 152 struct batadv_forw_packet *forw_packet, 153 unsigned long send_time) 154 { 155 INIT_HLIST_NODE(&forw_packet->list); 156 157 /* add new packet to packet list */ 158 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 159 hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list); 160 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 161 162 /* start timer for this packet */ 163 queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work, 164 send_time); 165 } 166 167 /* add a broadcast packet to the queue and setup timers. broadcast packets 168 * are sent multiple times to increase probability for being received. 169 * 170 * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on 171 * errors. 172 * 173 * The skb is not consumed, so the caller should make sure that the 174 * skb is freed. 175 */ 176 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, 177 const struct sk_buff *skb, 178 unsigned long delay) 179 { 180 struct batadv_hard_iface *primary_if = NULL; 181 struct batadv_forw_packet *forw_packet; 182 struct batadv_bcast_packet *bcast_packet; 183 struct sk_buff *newskb; 184 185 if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) { 186 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 187 "bcast packet queue full\n"); 188 goto out; 189 } 190 191 primary_if = batadv_primary_if_get_selected(bat_priv); 192 if (!primary_if) 193 goto out_and_inc; 194 195 forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC); 196 197 if (!forw_packet) 198 goto out_and_inc; 199 200 newskb = skb_copy(skb, GFP_ATOMIC); 201 if (!newskb) 202 goto packet_free; 203 204 /* as we have a copy now, it is safe to decrease the TTL */ 205 bcast_packet = (struct batadv_bcast_packet *)newskb->data; 206 bcast_packet->header.ttl--; 207 208 skb_reset_mac_header(newskb); 209 210 forw_packet->skb = newskb; 211 forw_packet->if_incoming = primary_if; 212 213 /* how often did we send the bcast packet ? */ 214 forw_packet->num_packets = 0; 215 216 INIT_DELAYED_WORK(&forw_packet->delayed_work, 217 batadv_send_outstanding_bcast_packet); 218 219 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay); 220 return NETDEV_TX_OK; 221 222 packet_free: 223 kfree(forw_packet); 224 out_and_inc: 225 atomic_inc(&bat_priv->bcast_queue_left); 226 out: 227 if (primary_if) 228 batadv_hardif_free_ref(primary_if); 229 return NETDEV_TX_BUSY; 230 } 231 232 static void batadv_send_outstanding_bcast_packet(struct work_struct *work) 233 { 234 struct batadv_hard_iface *hard_iface; 235 struct delayed_work *delayed_work; 236 struct batadv_forw_packet *forw_packet; 237 struct sk_buff *skb1; 238 struct net_device *soft_iface; 239 struct batadv_priv *bat_priv; 240 241 delayed_work = container_of(work, struct delayed_work, work); 242 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 243 delayed_work); 244 soft_iface = forw_packet->if_incoming->soft_iface; 245 bat_priv = netdev_priv(soft_iface); 246 247 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 248 hlist_del(&forw_packet->list); 249 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 250 251 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 252 goto out; 253 254 if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) 255 goto out; 256 257 /* rebroadcast packet */ 258 rcu_read_lock(); 259 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 260 if (hard_iface->soft_iface != soft_iface) 261 continue; 262 263 /* send a copy of the saved skb */ 264 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC); 265 if (skb1) 266 batadv_send_skb_packet(skb1, hard_iface, 267 batadv_broadcast_addr); 268 } 269 rcu_read_unlock(); 270 271 forw_packet->num_packets++; 272 273 /* if we still have some more bcasts to send */ 274 if (forw_packet->num_packets < 3) { 275 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, 276 msecs_to_jiffies(5)); 277 return; 278 } 279 280 out: 281 batadv_forw_packet_free(forw_packet); 282 atomic_inc(&bat_priv->bcast_queue_left); 283 } 284 285 void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work) 286 { 287 struct delayed_work *delayed_work; 288 struct batadv_forw_packet *forw_packet; 289 struct batadv_priv *bat_priv; 290 291 delayed_work = container_of(work, struct delayed_work, work); 292 forw_packet = container_of(delayed_work, struct batadv_forw_packet, 293 delayed_work); 294 bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface); 295 spin_lock_bh(&bat_priv->forw_bat_list_lock); 296 hlist_del(&forw_packet->list); 297 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 298 299 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) 300 goto out; 301 302 bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet); 303 304 /* we have to have at least one packet in the queue 305 * to determine the queues wake up time unless we are 306 * shutting down 307 */ 308 if (forw_packet->own) 309 batadv_schedule_bat_ogm(forw_packet->if_incoming); 310 311 out: 312 /* don't count own packet */ 313 if (!forw_packet->own) 314 atomic_inc(&bat_priv->batman_queue_left); 315 316 batadv_forw_packet_free(forw_packet); 317 } 318 319 void 320 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv, 321 const struct batadv_hard_iface *hard_iface) 322 { 323 struct batadv_forw_packet *forw_packet; 324 struct hlist_node *safe_tmp_node; 325 bool pending; 326 327 if (hard_iface) 328 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 329 "purge_outstanding_packets(): %s\n", 330 hard_iface->net_dev->name); 331 else 332 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, 333 "purge_outstanding_packets()\n"); 334 335 /* free bcast list */ 336 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 337 hlist_for_each_entry_safe(forw_packet, safe_tmp_node, 338 &bat_priv->forw_bcast_list, list) { 339 /* if purge_outstanding_packets() was called with an argument 340 * we delete only packets belonging to the given interface 341 */ 342 if ((hard_iface) && 343 (forw_packet->if_incoming != hard_iface)) 344 continue; 345 346 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 347 348 /* batadv_send_outstanding_bcast_packet() will lock the list to 349 * delete the item from the list 350 */ 351 pending = cancel_delayed_work_sync(&forw_packet->delayed_work); 352 spin_lock_bh(&bat_priv->forw_bcast_list_lock); 353 354 if (pending) { 355 hlist_del(&forw_packet->list); 356 batadv_forw_packet_free(forw_packet); 357 } 358 } 359 spin_unlock_bh(&bat_priv->forw_bcast_list_lock); 360 361 /* free batman packet list */ 362 spin_lock_bh(&bat_priv->forw_bat_list_lock); 363 hlist_for_each_entry_safe(forw_packet, safe_tmp_node, 364 &bat_priv->forw_bat_list, list) { 365 /* if purge_outstanding_packets() was called with an argument 366 * we delete only packets belonging to the given interface 367 */ 368 if ((hard_iface) && 369 (forw_packet->if_incoming != hard_iface)) 370 continue; 371 372 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 373 374 /* send_outstanding_bat_packet() will lock the list to 375 * delete the item from the list 376 */ 377 pending = cancel_delayed_work_sync(&forw_packet->delayed_work); 378 spin_lock_bh(&bat_priv->forw_bat_list_lock); 379 380 if (pending) { 381 hlist_del(&forw_packet->list); 382 batadv_forw_packet_free(forw_packet); 383 } 384 } 385 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 386 } 387