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 = buff_pos = 0;
 138         batman_packet = (struct batman_packet *)
 139                 (forw_packet->packet_buff);
 140
 141         /* adjust all flags and log packets */
 142         while (aggregated_packet(buff_pos,
 143                                  forw_packet->packet_len,
 144                                  batman_packet->num_hna)) {
 145
 146                 /* we might have aggregated direct link packets with an
 147                  * ordinary base packet */
 148                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 149                     (forw_packet->if_incoming == batman_if))
 150                         batman_packet->flags |= DIRECTLINK;
 151                 else
 152                         batman_packet->flags &= ~DIRECTLINK;
 153
 154                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 155                                                             "Sending own" :
 156                                                             "Forwarding"));
 157                 bat_dbg(DBG_BATMAN,
 158                         "%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d, IDF %s) on interface %s [%s]\n",
 159                         fwd_str,
 160                         (packet_num > 0 ? "aggregated " : ""),
 161                         batman_packet->orig, ntohs(batman_packet->seqno),
 162                         batman_packet->tq, batman_packet->ttl,
 163                         (batman_packet->flags & DIRECTLINK ?
 164                          "on" : "off"),
 165                         batman_if->dev, batman_if->addr_str);
 166
 167                 buff_pos += sizeof(struct batman_packet) +
 168                         (batman_packet->num_hna * ETH_ALEN);
 169                 packet_num++;
 170                 batman_packet = (struct batman_packet *)
 171                         (forw_packet->packet_buff + buff_pos);
 172         }
 173
 174         send_raw_packet(forw_packet->packet_buff,
 175                         forw_packet->packet_len,
 176                         batman_if, broadcastAddr);
 177 }
 178
 179 /* send a batman packet */
 180 static void send_packet(struct forw_packet *forw_packet)
 181 {
 182         struct batman_if *batman_if;
 183         struct batman_packet *batman_packet =
 184                 (struct batman_packet *)(forw_packet->packet_buff);
 185         unsigned char directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 186
 187         if (!forw_packet->if_incoming) {
 188                 printk(KERN_ERR "batman-adv: Error - can't forward packet: incoming iface not specified\n");
 189                 return;
 190         }
 191
 192         if (forw_packet->if_incoming->if_active != IF_ACTIVE)
 193                 return;
 194
 195         /* multihomed peer assumed */
 196         /* non-primary OGMs are only broadcasted on their interface */
 197         if ((directlink && (batman_packet->ttl == 1)) ||
 198             (forw_packet->own && (forw_packet->if_incoming->if_num > 0))) {
 199
 200                 /* FIXME: what about aggregated packets ? */
 201                 bat_dbg(DBG_BATMAN,
 202                         "%s packet (originator %pM, seqno %d, TTL %d) on interface %s [%s]\n",
 203                         (forw_packet->own ? "Sending own" : "Forwarding"),
 204                         batman_packet->orig, ntohs(batman_packet->seqno),
 205                         batman_packet->ttl, forw_packet->if_incoming->dev,
 206                         forw_packet->if_incoming->addr_str);
 207
 208                 send_raw_packet(forw_packet->packet_buff,
 209                                 forw_packet->packet_len,
 210                                 forw_packet->if_incoming,
 211                                 broadcastAddr);
 212                 return;
 213         }
 214
 215         /* broadcast on every interface */
 216         rcu_read_lock();
 217         list_for_each_entry_rcu(batman_if, &if_list, list)
 218                 send_packet_to_if(forw_packet, batman_if);
 219         rcu_read_unlock();
 220 }
 221
 222 static void rebuild_batman_packet(struct batman_if *batman_if)
 223 {
 224         int new_len;
 225         unsigned char *new_buff;
 226         struct batman_packet *batman_packet;
 227
 228         new_len = sizeof(struct batman_packet) + (num_hna * ETH_ALEN);
 229         new_buff = kmalloc(new_len, GFP_ATOMIC);
 230
 231         /* keep old buffer if kmalloc should fail */
 232         if (new_buff) {
 233                 memcpy(new_buff, batman_if->packet_buff,
 234                        sizeof(struct batman_packet));
 235                 batman_packet = (struct batman_packet *)new_buff;
 236
 237                 batman_packet->num_hna = hna_local_fill_buffer(
 238                         new_buff + sizeof(struct batman_packet),
 239                         new_len - sizeof(struct batman_packet));
 240
 241                 kfree(batman_if->packet_buff);
 242                 batman_if->packet_buff = new_buff;
 243                 batman_if->packet_len = new_len;
 244         }
 245 }
 246
 247 void schedule_own_packet(struct batman_if *batman_if)
 248 {
 249         unsigned long send_time;
 250         struct batman_packet *batman_packet;
 251         int vis_server = atomic_read(&vis_mode);
 252
 253         /**
 254          * the interface gets activated here to avoid race conditions between
 255          * the moment of activating the interface in
 256          * hardif_activate_interface() where the originator mac is set and
 257          * outdated packets (especially uninitialized mac addresses) in the
 258          * packet queue
 259          */
 260         if (batman_if->if_active == IF_TO_BE_ACTIVATED)
 261                 batman_if->if_active = IF_ACTIVE;
 262
 263         /* if local hna has changed and interface is a primary interface */
 264         if ((atomic_read(&hna_local_changed)) && (batman_if->if_num == 0))
 265                 rebuild_batman_packet(batman_if);
 266
 267         /**
 268          * NOTE: packet_buff might just have been re-allocated in
 269          * rebuild_batman_packet()
 270          */
 271         batman_packet = (struct batman_packet *)batman_if->packet_buff;
 272
 273         /* change sequence number to network order */
 274         batman_packet->seqno = htons((uint16_t)atomic_read(&batman_if->seqno));
 275
 276         if (vis_server == VIS_TYPE_SERVER_SYNC)
 277                 batman_packet->flags = VIS_SERVER;
 278         else
 279                 batman_packet->flags = 0;
 280
 281         /* could be read by receive_bat_packet() */
 282         atomic_inc(&batman_if->seqno);
 283
 284         slide_own_bcast_window(batman_if);
 285         send_time = own_send_time();
 286         add_bat_packet_to_list(batman_if->packet_buff,
 287                                batman_if->packet_len, batman_if, 1, send_time);
 288 }
 289
 290 void schedule_forward_packet(struct orig_node *orig_node,
 291                              struct ethhdr *ethhdr,
 292                              struct batman_packet *batman_packet,
 293                              uint8_t directlink, int hna_buff_len,
 294                              struct batman_if *if_incoming)
 295 {
 296         unsigned char in_tq, in_ttl, tq_avg = 0;
 297         unsigned long send_time;
 298
 299         if (batman_packet->ttl <= 1) {
 300                 bat_dbg(DBG_BATMAN, "ttl exceeded \n");
 301                 return;
 302         }
 303
 304         in_tq = batman_packet->tq;
 305         in_ttl = batman_packet->ttl;
 306
 307         batman_packet->ttl--;
 308         memcpy(batman_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 309
 310         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
 311          * of our best tq value */
 312         if ((orig_node->router) && (orig_node->router->tq_avg != 0)) {
 313
 314                 /* rebroadcast ogm of best ranking neighbor as is */
 315                 if (!compare_orig(orig_node->router->addr, ethhdr->h_source)) {
 316                         batman_packet->tq = orig_node->router->tq_avg;
 317
 318                         if (orig_node->router->last_ttl)
 319                                 batman_packet->ttl = orig_node->router->last_ttl - 1;
 320                 }
 321
 322                 tq_avg = orig_node->router->tq_avg;
 323         }
 324
 325         /* apply hop penalty */
 326         batman_packet->tq = hop_penalty(batman_packet->tq);
 327
 328         bat_dbg(DBG_BATMAN, "Forwarding packet: tq_orig: %i, tq_avg: %i, tq_forw: %i, ttl_orig: %i, ttl_forw: %i \n",
 329                 in_tq, tq_avg, batman_packet->tq, in_ttl - 1,
 330                 batman_packet->ttl);
 331
 332         batman_packet->seqno = htons(batman_packet->seqno);
 333
 334         if (directlink)
 335                 batman_packet->flags |= DIRECTLINK;
 336         else
 337                 batman_packet->flags &= ~DIRECTLINK;
 338
 339         send_time = forward_send_time();
 340         add_bat_packet_to_list((unsigned char *)batman_packet,
 341                                sizeof(struct batman_packet) + hna_buff_len,
 342                                if_incoming, 0, send_time);
 343 }
 344
 345 static void forw_packet_free(struct forw_packet *forw_packet)
 346 {
 347         if (forw_packet->skb)
 348                 kfree_skb(forw_packet->skb);
 349         kfree(forw_packet->packet_buff);
 350         kfree(forw_packet);
 351 }
 352
 353 static void _add_bcast_packet_to_list(struct forw_packet *forw_packet,
 354                                       unsigned long send_time)
 355 {
 356         unsigned long flags;
 357         INIT_HLIST_NODE(&forw_packet->list);
 358
 359         /* add new packet to packet list */
 360         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 361         hlist_add_head(&forw_packet->list, &forw_bcast_list);
 362         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 363
 364         /* start timer for this packet */
 365         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 366                           send_outstanding_bcast_packet);
 367         queue_delayed_work(bat_event_workqueue, &forw_packet->delayed_work,
 368                            send_time);
 369 }
 370
 371 void add_bcast_packet_to_list(struct sk_buff *skb)
 372 {
 373         struct forw_packet *forw_packet;
 374
 375         forw_packet = kmalloc(sizeof(struct forw_packet), GFP_ATOMIC);
 376         if (!forw_packet)
 377                 return;
 378
 379         skb = skb_copy(skb, GFP_ATOMIC);
 380         if (!skb) {
 381                 kfree(forw_packet);
 382                 return;
 383         }
 384
 385         skb_reset_mac_header(skb);
 386
 387         forw_packet->skb = skb;
 388         forw_packet->packet_buff = NULL;
 389
 390         /* how often did we send the bcast packet ? */
 391         forw_packet->num_packets = 0;
 392
 393         _add_bcast_packet_to_list(forw_packet, 1);
 394 }
 395
 396 void send_outstanding_bcast_packet(struct work_struct *work)
 397 {
 398         struct batman_if *batman_if;
 399         struct delayed_work *delayed_work =
 400                 container_of(work, struct delayed_work, work);
 401         struct forw_packet *forw_packet =
 402                 container_of(delayed_work, struct forw_packet, delayed_work);
 403         unsigned long flags;
 404         struct sk_buff *skb1;
 405
 406         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 407         hlist_del(&forw_packet->list);
 408         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 409
 410         /* rebroadcast packet */
 411         rcu_read_lock();
 412         list_for_each_entry_rcu(batman_if, &if_list, list) {
 413                 /* send a copy of the saved skb */
 414                 skb1 = skb_copy(forw_packet->skb, GFP_ATOMIC);
 415                 if (skb1)
 416                         send_skb_packet(skb1,
 417                                 batman_if, broadcastAddr);
 418         }
 419         rcu_read_unlock();
 420
 421         forw_packet->num_packets++;
 422
 423         /* if we still have some more bcasts to send and we are not shutting
 424          * down */
 425         if ((forw_packet->num_packets < 3) &&
 426             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 427                 _add_bcast_packet_to_list(forw_packet, ((5 * HZ) / 1000));
 428         else
 429                 forw_packet_free(forw_packet);
 430 }
 431
 432 void send_outstanding_bat_packet(struct work_struct *work)
 433 {
 434         struct delayed_work *delayed_work =
 435                 container_of(work, struct delayed_work, work);
 436         struct forw_packet *forw_packet =
 437                 container_of(delayed_work, struct forw_packet, delayed_work);
 438         unsigned long flags;
 439
 440         spin_lock_irqsave(&forw_bat_list_lock, flags);
 441         hlist_del(&forw_packet->list);
 442         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 443
 444         send_packet(forw_packet);
 445
 446         /**
 447          * we have to have at least one packet in the queue
 448          * to determine the queues wake up time unless we are
 449          * shutting down
 450          */
 451         if ((forw_packet->own) &&
 452             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 453                 schedule_own_packet(forw_packet->if_incoming);
 454
 455         forw_packet_free(forw_packet);
 456 }
 457
 458 void purge_outstanding_packets(void)
 459 {
 460         struct forw_packet *forw_packet;
 461         struct hlist_node *tmp_node, *safe_tmp_node;
 462         unsigned long flags;
 463
 464         bat_dbg(DBG_BATMAN, "purge_outstanding_packets()\n");
 465
 466         /* free bcast list */
 467         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 468         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 469                                   &forw_bcast_list, list) {
 470
 471                 spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 472
 473                 /**
 474                  * send_outstanding_bcast_packet() will lock the list to
 475                  * delete the item from the list
 476                  */
 477                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 478                 spin_lock_irqsave(&forw_bcast_list_lock, flags);
 479         }
 480         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 481
 482         /* free batman packet list */
 483         spin_lock_irqsave(&forw_bat_list_lock, flags);
 484         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 485                                   &forw_bat_list, list) {
 486
 487                 spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 488
 489                 /**
 490                  * send_outstanding_bat_packet() will lock the list to
 491                  * delete the item from the list
 492                  */
 493                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 494                 spin_lock_irqsave(&forw_bat_list_lock, flags);
 495         }
 496         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 497 }