drivers/staging/batman-adv/send.c

   1 /*
   2  * Copyright (C) 2007-2009 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "send.h"
  24 #include "routing.h"
  25 #include "translation-table.h"
  26 #include "soft-interface.h"
  27 #include "hard-interface.h"
  28 #include "types.h"
  29 #include "vis.h"
  30 #include "aggregation.h"
  31
  32 /* apply hop penalty for a normal link */
  33 static uint8_t hop_penalty(const uint8_t tq)
  34 {
  35         return (tq * (TQ_MAX_VALUE - TQ_HOP_PENALTY)) / (TQ_MAX_VALUE);
  36 }
  37
  38 /* when do we schedule our own packet to be sent */
  39 static unsigned long own_send_time(void)
  40 {
  41         return jiffies +
  42                 (((atomic_read(&originator_interval) - JITTER +
  43                    (random32() % 2*JITTER)) * HZ) / 1000);
  44 }
  45
  46 /* when do we schedule a forwarded packet to be sent */
  47 static unsigned long forward_send_time(void)
  48 {
  49         unsigned long send_time = jiffies; /* Starting now plus... */
  50
  51         if (atomic_read(&aggregation_enabled))
  52                 send_time += (((MAX_AGGREGATION_MS - (JITTER/2) +
  53                                 (random32() % JITTER)) * HZ) / 1000);
  54         else
  55                 send_time += (((random32() % (JITTER/2)) * HZ) / 1000);
  56
  57         return send_time;
  58 }
  59
  60 /* send out an already prepared packet to the given address via the
  61  * specified batman interface */
  62 int send_skb_packet(struct sk_buff *skb,
  63                                 struct batman_if *batman_if,
  64                                 uint8_t *dst_addr)
  65 {
  66         struct ethhdr *ethhdr;
  67
  68         if (batman_if->if_active != IF_ACTIVE)
  69                 goto send_skb_err;
  70
  71         if (unlikely(!batman_if->net_dev))
  72                 goto send_skb_err;
  73
  74         if (!(batman_if->net_dev->flags & IFF_UP)) {
  75                 printk(KERN_WARNING
  76                        "batman-adv:Interface %s is not up - can't send packet via that interface!\n",
  77                        batman_if->dev);
  78                 goto send_skb_err;
  79         }
  80
  81         /* push to the ethernet header. */
  82         if (my_skb_push(skb, sizeof(struct ethhdr)) < 0)
  83                 goto send_skb_err;
  84
  85         skb_reset_mac_header(skb);
  86
  87         ethhdr = (struct ethhdr *) skb_mac_header(skb);
  88         memcpy(ethhdr->h_source, batman_if->net_dev->dev_addr, ETH_ALEN);
  89         memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN);
  90         ethhdr->h_proto = __constant_htons(ETH_P_BATMAN);
  91
  92         skb_set_network_header(skb, ETH_HLEN);
  93         skb->priority = TC_PRIO_CONTROL;
  94         skb->protocol = __constant_htons(ETH_P_BATMAN);
  95
  96         skb->dev = batman_if->net_dev;
  97
  98         /* dev_queue_xmit() returns a negative result on error.  However on
  99          * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
 100          * (which is > 0). This will not be treated as an error. */
 101
 102         return dev_queue_xmit(skb);
 103 send_skb_err:
 104         kfree_skb(skb);
 105         return NET_XMIT_DROP;
 106 }
 107
 108 /* sends a raw packet. */
 109 void send_raw_packet(unsigned char *pack_buff, int pack_buff_len,
 110                      struct batman_if *batman_if, uint8_t *dst_addr)
 111 {
 112         struct sk_buff *skb;
 113         char *data;
 114
 115         skb = dev_alloc_skb(pack_buff_len + sizeof(struct ethhdr));
 116         if (!skb)
 117                 return;
 118         data = skb_put(skb, pack_buff_len + sizeof(struct ethhdr));
 119         memcpy(data + sizeof(struct ethhdr), pack_buff, pack_buff_len);
 120         /* pull back to the batman "network header" */
 121         skb_pull(skb, sizeof(struct ethhdr));
 122         send_skb_packet(skb, batman_if, dst_addr);
 123 }
 124
 125 /* Send a packet to a given interface */
 126 static void send_packet_to_if(struct forw_packet *forw_packet,
 127                               struct batman_if *batman_if)
 128 {
 129         char *fwd_str;
 130         uint8_t packet_num;
 131         int16_t buff_pos;
 132         struct batman_packet *batman_packet;
 133
 134         if (batman_if->if_active != IF_ACTIVE)
 135                 return;
 136
 137         packet_num = 0;
 138         buff_pos = 0;
 139         batman_packet = (struct batman_packet *)
 140                 (forw_packet->packet_buff);
 141
 142         /* adjust all flags and log packets */
 143         while (aggregated_packet(buff_pos,
 144                                  forw_packet->packet_len,
 145                                  batman_packet->num_hna)) {
 146
 147                 /* we might have aggregated direct link packets with an
 148                  * ordinary base packet */
 149                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 150                     (forw_packet->if_incoming == batman_if))
 151                         batman_packet->flags |= DIRECTLINK;
 152                 else
 153                         batman_packet->flags &= ~DIRECTLINK;
 154
 155                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 156                                                             "Sending own" :
 157                                                             "Forwarding"));
 158                 bat_dbg(DBG_BATMAN,
 159                         "%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d, IDF %s) on interface %s [%s]\n",
 160                         fwd_str,
 161                         (packet_num > 0 ? "aggregated " : ""),
 162                         batman_packet->orig, ntohs(batman_packet->seqno),
 163                         batman_packet->tq, batman_packet->ttl,
 164                         (batman_packet->flags & DIRECTLINK ?
 165                          "on" : "off"),
 166                         batman_if->dev, batman_if->addr_str);
 167
 168                 buff_pos += sizeof(struct batman_packet) +
 169                         (batman_packet->num_hna * ETH_ALEN);
 170                 packet_num++;
 171                 batman_packet = (struct batman_packet *)
 172                         (forw_packet->packet_buff + buff_pos);
 173         }
 174
 175         send_raw_packet(forw_packet->packet_buff,
 176                         forw_packet->packet_len,
 177                         batman_if, broadcastAddr);
 178 }
 179
 180 /* send a batman packet */
 181 static void send_packet(struct forw_packet *forw_packet)
 182 {
 183         struct batman_if *batman_if;
 184         struct batman_packet *batman_packet =
 185                 (struct batman_packet *)(forw_packet->packet_buff);
 186         unsigned char directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 187
 188         if (!forw_packet->if_incoming) {
 189                 printk(KERN_ERR "batman-adv: Error - can't forward packet: incoming iface not specified\n");
 190                 return;
 191         }
 192
 193         if (forw_packet->if_incoming->if_active != IF_ACTIVE)
 194                 return;
 195
 196         /* multihomed peer assumed */
 197         /* non-primary OGMs are only broadcasted on their interface */
 198         if ((directlink && (batman_packet->ttl == 1)) ||
 199             (forw_packet->own && (forw_packet->if_incoming->if_num > 0))) {
 200
 201                 /* FIXME: what about aggregated packets ? */
 202                 bat_dbg(DBG_BATMAN,
 203                         "%s packet (originator %pM, seqno %d, TTL %d) on interface %s [%s]\n",
 204                         (forw_packet->own ? "Sending own" : "Forwarding"),
 205                         batman_packet->orig, ntohs(batman_packet->seqno),
 206                         batman_packet->ttl, forw_packet->if_incoming->dev,
 207                         forw_packet->if_incoming->addr_str);
 208
 209                 send_raw_packet(forw_packet->packet_buff,
 210                                 forw_packet->packet_len,
 211                                 forw_packet->if_incoming,
 212                                 broadcastAddr);
 213                 return;
 214         }
 215
 216         /* broadcast on every interface */
 217         rcu_read_lock();
 218         list_for_each_entry_rcu(batman_if, &if_list, list)
 219                 send_packet_to_if(forw_packet, batman_if);
 220         rcu_read_unlock();
 221 }
 222
 223 static void rebuild_batman_packet(struct batman_if *batman_if)
 224 {
 225         int new_len;
 226         unsigned char *new_buff;
 227         struct batman_packet *batman_packet;
 228
 229         new_len = sizeof(struct batman_packet) + (num_hna * ETH_ALEN);
 230         new_buff = kmalloc(new_len, GFP_ATOMIC);
 231
 232         /* keep old buffer if kmalloc should fail */
 233         if (new_buff) {
 234                 memcpy(new_buff, batman_if->packet_buff,
 235                        sizeof(struct batman_packet));
 236                 batman_packet = (struct batman_packet *)new_buff;
 237
 238                 batman_packet->num_hna = hna_local_fill_buffer(
 239                         new_buff + sizeof(struct batman_packet),
 240                         new_len - sizeof(struct batman_packet));
 241
 242                 kfree(batman_if->packet_buff);
 243                 batman_if->packet_buff = new_buff;
 244                 batman_if->packet_len = new_len;
 245         }
 246 }
 247
 248 void schedule_own_packet(struct batman_if *batman_if)
 249 {
 250         unsigned long send_time;
 251         struct batman_packet *batman_packet;
 252         int vis_server = atomic_read(&vis_mode);
 253
 254         /**
 255          * the interface gets activated here to avoid race conditions between
 256          * the moment of activating the interface in
 257          * hardif_activate_interface() where the originator mac is set and
 258          * outdated packets (especially uninitialized mac addresses) in the
 259          * packet queue
 260          */
 261         if (batman_if->if_active == IF_TO_BE_ACTIVATED)
 262                 batman_if->if_active = IF_ACTIVE;
 263
 264         /* if local hna has changed and interface is a primary interface */
 265         if ((atomic_read(&hna_local_changed)) && (batman_if->if_num == 0))
 266                 rebuild_batman_packet(batman_if);
 267
 268         /**
 269          * NOTE: packet_buff might just have been re-allocated in
 270          * rebuild_batman_packet()
 271          */
 272         batman_packet = (struct batman_packet *)batman_if->packet_buff;
 273
 274         /* change sequence number to network order */
 275         batman_packet->seqno = htons((uint16_t)atomic_read(&batman_if->seqno));
 276
 277         if (vis_server == VIS_TYPE_SERVER_SYNC)
 278                 batman_packet->flags = VIS_SERVER;
 279         else
 280                 batman_packet->flags = 0;
 281
 282         /* could be read by receive_bat_packet() */
 283         atomic_inc(&batman_if->seqno);
 284
 285         slide_own_bcast_window(batman_if);
 286         send_time = own_send_time();
 287         add_bat_packet_to_list(batman_if->packet_buff,
 288                                batman_if->packet_len, batman_if, 1, send_time);
 289 }
 290
 291 void schedule_forward_packet(struct orig_node *orig_node,
 292                              struct ethhdr *ethhdr,
 293                              struct batman_packet *batman_packet,
 294                              uint8_t directlink, int hna_buff_len,
 295                              struct batman_if *if_incoming)
 296 {
 297         unsigned char in_tq, in_ttl, tq_avg = 0;
 298         unsigned long send_time;
 299
 300         if (batman_packet->ttl <= 1) {
 301                 bat_dbg(DBG_BATMAN, "ttl exceeded \n");
 302                 return;
 303         }
 304
 305         in_tq = batman_packet->tq;
 306         in_ttl = batman_packet->ttl;
 307
 308         batman_packet->ttl--;
 309         memcpy(batman_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 310
 311         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
 312          * of our best tq value */
 313         if ((orig_node->router) && (orig_node->router->tq_avg != 0)) {
 314
 315                 /* rebroadcast ogm of best ranking neighbor as is */
 316                 if (!compare_orig(orig_node->router->addr, ethhdr->h_source)) {
 317                         batman_packet->tq = orig_node->router->tq_avg;
 318
 319                         if (orig_node->router->last_ttl)
 320                                 batman_packet->ttl = orig_node->router->last_ttl - 1;
 321                 }
 322
 323                 tq_avg = orig_node->router->tq_avg;
 324         }
 325
 326         /* apply hop penalty */
 327         batman_packet->tq = hop_penalty(batman_packet->tq);
 328
 329         bat_dbg(DBG_BATMAN, "Forwarding packet: tq_orig: %i, tq_avg: %i, tq_forw: %i, ttl_orig: %i, ttl_forw: %i \n",
 330                 in_tq, tq_avg, batman_packet->tq, in_ttl - 1,
 331                 batman_packet->ttl);
 332
 333         batman_packet->seqno = htons(batman_packet->seqno);
 334
 335         if (directlink)
 336                 batman_packet->flags |= DIRECTLINK;
 337         else
 338                 batman_packet->flags &= ~DIRECTLINK;
 339
 340         send_time = forward_send_time();
 341         add_bat_packet_to_list((unsigned char *)batman_packet,
 342                                sizeof(struct batman_packet) + hna_buff_len,
 343                                if_incoming, 0, send_time);
 344 }
 345
 346 static void forw_packet_free(struct forw_packet *forw_packet)
 347 {
 348         if (forw_packet->skb)
 349                 kfree_skb(forw_packet->skb);
 350         kfree(forw_packet->packet_buff);
 351         kfree(forw_packet);
 352 }
 353
 354 static void _add_bcast_packet_to_list(struct forw_packet *forw_packet,
 355                                       unsigned long send_time)
 356 {
 357         unsigned long flags;
 358         INIT_HLIST_NODE(&forw_packet->list);
 359
 360         /* add new packet to packet list */
 361         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 362         hlist_add_head(&forw_packet->list, &forw_bcast_list);
 363         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 364
 365         /* start timer for this packet */
 366         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 367                           send_outstanding_bcast_packet);
 368         queue_delayed_work(bat_event_workqueue, &forw_packet->delayed_work,
 369                            send_time);
 370 }
 371
 372 void add_bcast_packet_to_list(struct sk_buff *skb)
 373 {
 374         struct forw_packet *forw_packet;
 375
 376         forw_packet = kmalloc(sizeof(struct forw_packet), GFP_ATOMIC);
 377         if (!forw_packet)
 378                 return;
 379
 380         skb = skb_copy(skb, GFP_ATOMIC);
 381         if (!skb) {
 382                 kfree(forw_packet);
 383                 return;
 384         }
 385
 386         skb_reset_mac_header(skb);
 387
 388         forw_packet->skb = skb;
 389         forw_packet->packet_buff = NULL;
 390
 391         /* how often did we send the bcast packet ? */
 392         forw_packet->num_packets = 0;
 393
 394         _add_bcast_packet_to_list(forw_packet, 1);
 395 }
 396
 397 void send_outstanding_bcast_packet(struct work_struct *work)
 398 {
 399         struct batman_if *batman_if;
 400         struct delayed_work *delayed_work =
 401                 container_of(work, struct delayed_work, work);
 402         struct forw_packet *forw_packet =
 403                 container_of(delayed_work, struct forw_packet, delayed_work);
 404         unsigned long flags;
 405         struct sk_buff *skb1;
 406
 407         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 408         hlist_del(&forw_packet->list);
 409         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 410
 411         /* rebroadcast packet */
 412         rcu_read_lock();
 413         list_for_each_entry_rcu(batman_if, &if_list, list) {
 414                 /* send a copy of the saved skb */
 415                 skb1 = skb_copy(forw_packet->skb, GFP_ATOMIC);
 416                 if (skb1)
 417                         send_skb_packet(skb1,
 418                                 batman_if, broadcastAddr);
 419         }
 420         rcu_read_unlock();
 421
 422         forw_packet->num_packets++;
 423
 424         /* if we still have some more bcasts to send and we are not shutting
 425          * down */
 426         if ((forw_packet->num_packets < 3) &&
 427             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 428                 _add_bcast_packet_to_list(forw_packet, ((5 * HZ) / 1000));
 429         else
 430                 forw_packet_free(forw_packet);
 431 }
 432
 433 void send_outstanding_bat_packet(struct work_struct *work)
 434 {
 435         struct delayed_work *delayed_work =
 436                 container_of(work, struct delayed_work, work);
 437         struct forw_packet *forw_packet =
 438                 container_of(delayed_work, struct forw_packet, delayed_work);
 439         unsigned long flags;
 440
 441         spin_lock_irqsave(&forw_bat_list_lock, flags);
 442         hlist_del(&forw_packet->list);
 443         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 444
 445         send_packet(forw_packet);
 446
 447         /**
 448          * we have to have at least one packet in the queue
 449          * to determine the queues wake up time unless we are
 450          * shutting down
 451          */
 452         if ((forw_packet->own) &&
 453             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 454                 schedule_own_packet(forw_packet->if_incoming);
 455
 456         forw_packet_free(forw_packet);
 457 }
 458
 459 void purge_outstanding_packets(void)
 460 {
 461         struct forw_packet *forw_packet;
 462         struct hlist_node *tmp_node, *safe_tmp_node;
 463         unsigned long flags;
 464
 465         bat_dbg(DBG_BATMAN, "purge_outstanding_packets()\n");
 466
 467         /* free bcast list */
 468         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 469         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 470                                   &forw_bcast_list, list) {
 471
 472                 spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 473
 474                 /**
 475                  * send_outstanding_bcast_packet() will lock the list to
 476                  * delete the item from the list
 477                  */
 478                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 479                 spin_lock_irqsave(&forw_bcast_list_lock, flags);
 480         }
 481         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 482
 483         /* free batman packet list */
 484         spin_lock_irqsave(&forw_bat_list_lock, flags);
 485         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 486                                   &forw_bat_list, list) {
 487
 488                 spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 489
 490                 /**
 491                  * send_outstanding_bat_packet() will lock the list to
 492                  * delete the item from the list
 493                  */
 494                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 495                 spin_lock_irqsave(&forw_bat_list_lock, flags);
 496         }
 497         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 498 }