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 #include "compat.h"
  33
  34 /* apply hop penalty for a normal link */
  35 static uint8_t hop_penalty(const uint8_t tq)
  36 {
  37         return (tq * (TQ_MAX_VALUE - TQ_HOP_PENALTY)) / (TQ_MAX_VALUE);
  38 }
  39
  40 /* when do we schedule our own packet to be sent */
  41 static unsigned long own_send_time(void)
  42 {
  43         return jiffies +
  44                 (((atomic_read(&originator_interval) - JITTER +
  45                    (random32() % 2*JITTER)) * HZ) / 1000);
  46 }
  47
  48 /* when do we schedule a forwarded packet to be sent */
  49 static unsigned long forward_send_time(void)
  50 {
  51         unsigned long send_time = jiffies; /* Starting now plus... */
  52
  53         if (atomic_read(&aggregation_enabled))
  54                 send_time += (((MAX_AGGREGATION_MS - (JITTER/2) +
  55                                 (random32() % JITTER)) * HZ) / 1000);
  56         else
  57                 send_time += (((random32() % (JITTER/2)) * HZ) / 1000);
  58
  59         return send_time;
  60 }
  61
  62 /* send out an already prepared packet to the given address via the
  63  * specified batman interface */
  64 int send_skb_packet(struct sk_buff *skb,
  65                                 struct batman_if *batman_if,
  66                                 uint8_t *dst_addr)
  67 {
  68         struct ethhdr *ethhdr;
  69
  70         if (batman_if->if_active != IF_ACTIVE)
  71                 goto send_skb_err;
  72
  73         if (unlikely(!batman_if->net_dev))
  74                 goto send_skb_err;
  75
  76         if (!(batman_if->net_dev->flags & IFF_UP)) {
  77                 printk(KERN_WARNING
  78                        "batman-adv:Interface %s is not up - can't send packet via that interface!\n",
  79                        batman_if->dev);
  80                 goto send_skb_err;
  81         }
  82
  83         /* push to the ethernet header. */
  84         if (my_skb_push(skb, sizeof(struct ethhdr)) < 0)
  85                 goto send_skb_err;
  86
  87         skb_reset_mac_header(skb);
  88
  89         ethhdr = (struct ethhdr *) skb_mac_header(skb);
  90         memcpy(ethhdr->h_source, batman_if->net_dev->dev_addr, ETH_ALEN);
  91         memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN);
  92         ethhdr->h_proto = __constant_htons(ETH_P_BATMAN);
  93
  94         skb_set_network_header(skb, ETH_HLEN);
  95         skb->priority = TC_PRIO_CONTROL;
  96         skb->protocol = __constant_htons(ETH_P_BATMAN);
  97
  98         skb->dev = batman_if->net_dev;
  99
 100         /* dev_queue_xmit() returns a negative result on error.  However on
 101          * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
 102          * (which is > 0). This will not be treated as an error. */
 103
 104         return dev_queue_xmit(skb);
 105 send_skb_err:
 106         kfree_skb(skb);
 107         return NET_XMIT_DROP;
 108 }
 109
 110 /* sends a raw packet. */
 111 void send_raw_packet(unsigned char *pack_buff, int pack_buff_len,
 112                      struct batman_if *batman_if, uint8_t *dst_addr)
 113 {
 114         struct sk_buff *skb;
 115         char *data;
 116
 117         skb = dev_alloc_skb(pack_buff_len + sizeof(struct ethhdr));
 118         if (!skb)
 119                 return;
 120         data = skb_put(skb, pack_buff_len + sizeof(struct ethhdr));
 121         memcpy(data + sizeof(struct ethhdr), pack_buff, pack_buff_len);
 122         /* pull back to the batman "network header" */
 123         skb_pull(skb, sizeof(struct ethhdr));
 124         send_skb_packet(skb, batman_if, dst_addr);
 125 }
 126
 127 /* Send a packet to a given interface */
 128 static void send_packet_to_if(struct forw_packet *forw_packet,
 129                               struct batman_if *batman_if)
 130 {
 131         char *fwd_str;
 132         uint8_t packet_num;
 133         int16_t buff_pos;
 134         struct batman_packet *batman_packet;
 135         char orig_str[ETH_STR_LEN];
 136
 137         if (batman_if->if_active != IF_ACTIVE)
 138                 return;
 139
 140         packet_num = buff_pos = 0;
 141         batman_packet = (struct batman_packet *)
 142                 (forw_packet->packet_buff);
 143
 144         /* adjust all flags and log packets */
 145         while (aggregated_packet(buff_pos,
 146                                  forw_packet->packet_len,
 147                                  batman_packet->num_hna)) {
 148
 149                 /* we might have aggregated direct link packets with an
 150                  * ordinary base packet */
 151                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 152                     (forw_packet->if_incoming == batman_if))
 153                         batman_packet->flags |= DIRECTLINK;
 154                 else
 155                         batman_packet->flags &= ~DIRECTLINK;
 156
 157                 addr_to_string(orig_str, batman_packet->orig);
 158                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 159                                                             "Sending own" :
 160                                                             "Forwarding"));
 161                 bat_dbg(DBG_BATMAN,
 162                         "%s %spacket (originator %s, seqno %d, TQ %d, TTL %d, IDF %s) on interface %s [%s]\n",
 163                         fwd_str,
 164                         (packet_num > 0 ? "aggregated " : ""),
 165                         orig_str, ntohs(batman_packet->seqno),
 166                         batman_packet->tq, batman_packet->ttl,
 167                         (batman_packet->flags & DIRECTLINK ?
 168                          "on" : "off"),
 169                         batman_if->dev, batman_if->addr_str);
 170
 171                 buff_pos += sizeof(struct batman_packet) +
 172                         (batman_packet->num_hna * ETH_ALEN);
 173                 packet_num++;
 174                 batman_packet = (struct batman_packet *)
 175                         (forw_packet->packet_buff + buff_pos);
 176         }
 177
 178         send_raw_packet(forw_packet->packet_buff,
 179                         forw_packet->packet_len,
 180                         batman_if, broadcastAddr);
 181 }
 182
 183 /* send a batman packet */
 184 static void send_packet(struct forw_packet *forw_packet)
 185 {
 186         struct batman_if *batman_if;
 187         struct batman_packet *batman_packet =
 188                 (struct batman_packet *)(forw_packet->packet_buff);
 189         char orig_str[ETH_STR_LEN];
 190         unsigned char directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 191
 192         if (!forw_packet->if_incoming) {
 193                 printk(KERN_ERR "batman-adv: Error - can't forward packet: incoming iface not specified\n");
 194                 return;
 195         }
 196
 197         if (forw_packet->if_incoming->if_active != IF_ACTIVE)
 198                 return;
 199
 200         addr_to_string(orig_str, batman_packet->orig);
 201
 202         /* multihomed peer assumed */
 203         /* non-primary OGMs are only broadcasted on their interface */
 204         if ((directlink && (batman_packet->ttl == 1)) ||
 205             (forw_packet->own && (forw_packet->if_incoming->if_num > 0))) {
 206
 207                 /* FIXME: what about aggregated packets ? */
 208                 bat_dbg(DBG_BATMAN,
 209                         "%s packet (originator %s, seqno %d, TTL %d) on interface %s [%s]\n",
 210                         (forw_packet->own ? "Sending own" : "Forwarding"),
 211                         orig_str, ntohs(batman_packet->seqno),
 212                         batman_packet->ttl, forw_packet->if_incoming->dev,
 213                         forw_packet->if_incoming->addr_str);
 214
 215                 send_raw_packet(forw_packet->packet_buff,
 216                                 forw_packet->packet_len,
 217                                 forw_packet->if_incoming,
 218                                 broadcastAddr);
 219                 return;
 220         }
 221
 222         /* broadcast on every interface */
 223         rcu_read_lock();
 224         list_for_each_entry_rcu(batman_if, &if_list, list)
 225                 send_packet_to_if(forw_packet, batman_if);
 226         rcu_read_unlock();
 227 }
 228
 229 static void rebuild_batman_packet(struct batman_if *batman_if)
 230 {
 231         int new_len;
 232         unsigned char *new_buff;
 233         struct batman_packet *batman_packet;
 234
 235         new_len = sizeof(struct batman_packet) + (num_hna * ETH_ALEN);
 236         new_buff = kmalloc(new_len, GFP_ATOMIC);
 237
 238         /* keep old buffer if kmalloc should fail */
 239         if (new_buff) {
 240                 memcpy(new_buff, batman_if->packet_buff,
 241                        sizeof(struct batman_packet));
 242                 batman_packet = (struct batman_packet *)new_buff;
 243
 244                 batman_packet->num_hna = hna_local_fill_buffer(
 245                         new_buff + sizeof(struct batman_packet),
 246                         new_len - sizeof(struct batman_packet));
 247
 248                 kfree(batman_if->packet_buff);
 249                 batman_if->packet_buff = new_buff;
 250                 batman_if->packet_len = new_len;
 251         }
 252 }
 253
 254 void schedule_own_packet(struct batman_if *batman_if)
 255 {
 256         unsigned long send_time;
 257         struct batman_packet *batman_packet;
 258
 259         /**
 260          * the interface gets activated here to avoid race conditions between
 261          * the moment of activating the interface in
 262          * hardif_activate_interface() where the originator mac is set and
 263          * outdated packets (especially uninitialized mac addresses) in the
 264          * packet queue
 265          */
 266         if (batman_if->if_active == IF_TO_BE_ACTIVATED)
 267                 batman_if->if_active = IF_ACTIVE;
 268
 269         /* if local hna has changed and interface is a primary interface */
 270         if ((atomic_read(&hna_local_changed)) && (batman_if->if_num == 0))
 271                 rebuild_batman_packet(batman_if);
 272
 273         /**
 274          * NOTE: packet_buff might just have been re-allocated in
 275          * rebuild_batman_packet()
 276          */
 277         batman_packet = (struct batman_packet *)batman_if->packet_buff;
 278
 279         /* change sequence number to network order */
 280         batman_packet->seqno = htons((uint16_t)atomic_read(&batman_if->seqno));
 281
 282         if (is_vis_server())
 283                 batman_packet->flags = VIS_SERVER;
 284         else
 285                 batman_packet->flags = 0;
 286
 287         /* could be read by receive_bat_packet() */
 288         atomic_inc(&batman_if->seqno);
 289
 290         slide_own_bcast_window(batman_if);
 291         send_time = own_send_time();
 292         add_bat_packet_to_list(batman_if->packet_buff,
 293                                batman_if->packet_len, batman_if, 1, send_time);
 294 }
 295
 296 void schedule_forward_packet(struct orig_node *orig_node,
 297                              struct ethhdr *ethhdr,
 298                              struct batman_packet *batman_packet,
 299                              uint8_t directlink, int hna_buff_len,
 300                              struct batman_if *if_incoming)
 301 {
 302         unsigned char in_tq, in_ttl, tq_avg = 0;
 303         unsigned long send_time;
 304
 305         if (batman_packet->ttl <= 1) {
 306                 bat_dbg(DBG_BATMAN, "ttl exceeded \n");
 307                 return;
 308         }
 309
 310         in_tq = batman_packet->tq;
 311         in_ttl = batman_packet->ttl;
 312
 313         batman_packet->ttl--;
 314         memcpy(batman_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 315
 316         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
 317          * of our best tq value */
 318         if ((orig_node->router) && (orig_node->router->tq_avg != 0)) {
 319
 320                 /* rebroadcast ogm of best ranking neighbor as is */
 321                 if (!compare_orig(orig_node->router->addr, ethhdr->h_source)) {
 322                         batman_packet->tq = orig_node->router->tq_avg;
 323
 324                         if (orig_node->router->last_ttl)
 325                                 batman_packet->ttl = orig_node->router->last_ttl - 1;
 326                 }
 327
 328                 tq_avg = orig_node->router->tq_avg;
 329         }
 330
 331         /* apply hop penalty */
 332         batman_packet->tq = hop_penalty(batman_packet->tq);
 333
 334         bat_dbg(DBG_BATMAN, "Forwarding packet: tq_orig: %i, tq_avg: %i, tq_forw: %i, ttl_orig: %i, ttl_forw: %i \n",
 335                 in_tq, tq_avg, batman_packet->tq, in_ttl - 1,
 336                 batman_packet->ttl);
 337
 338         batman_packet->seqno = htons(batman_packet->seqno);
 339
 340         if (directlink)
 341                 batman_packet->flags |= DIRECTLINK;
 342         else
 343                 batman_packet->flags &= ~DIRECTLINK;
 344
 345         send_time = forward_send_time();
 346         add_bat_packet_to_list((unsigned char *)batman_packet,
 347                                sizeof(struct batman_packet) + hna_buff_len,
 348                                if_incoming, 0, send_time);
 349 }
 350
 351 static void forw_packet_free(struct forw_packet *forw_packet)
 352 {
 353         if (forw_packet->skb)
 354                 kfree_skb(forw_packet->skb);
 355         kfree(forw_packet->packet_buff);
 356         kfree(forw_packet);
 357 }
 358
 359 static void _add_bcast_packet_to_list(struct forw_packet *forw_packet,
 360                                       unsigned long send_time)
 361 {
 362         unsigned long flags;
 363         INIT_HLIST_NODE(&forw_packet->list);
 364
 365         /* add new packet to packet list */
 366         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 367         hlist_add_head(&forw_packet->list, &forw_bcast_list);
 368         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 369
 370         /* start timer for this packet */
 371         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 372                           send_outstanding_bcast_packet);
 373         queue_delayed_work(bat_event_workqueue, &forw_packet->delayed_work,
 374                            send_time);
 375 }
 376
 377 void add_bcast_packet_to_list(struct sk_buff *skb)
 378 {
 379         struct forw_packet *forw_packet;
 380
 381         forw_packet = kmalloc(sizeof(struct forw_packet), GFP_ATOMIC);
 382         if (!forw_packet)
 383                 return;
 384
 385         skb = skb_copy(skb, GFP_ATOMIC);
 386         if (!skb) {
 387                 kfree(forw_packet);
 388                 return;
 389         }
 390
 391         skb_reset_mac_header(skb);
 392
 393         forw_packet->skb = skb;
 394         forw_packet->packet_buff = NULL;
 395
 396         /* how often did we send the bcast packet ? */
 397         forw_packet->num_packets = 0;
 398
 399         _add_bcast_packet_to_list(forw_packet, 1);
 400 }
 401
 402 void send_outstanding_bcast_packet(struct work_struct *work)
 403 {
 404         struct batman_if *batman_if;
 405         struct delayed_work *delayed_work =
 406                 container_of(work, struct delayed_work, work);
 407         struct forw_packet *forw_packet =
 408                 container_of(delayed_work, struct forw_packet, delayed_work);
 409         unsigned long flags;
 410         struct sk_buff *skb1;
 411
 412         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 413         hlist_del(&forw_packet->list);
 414         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 415
 416         /* rebroadcast packet */
 417         rcu_read_lock();
 418         list_for_each_entry_rcu(batman_if, &if_list, list) {
 419                 /* send a copy of the saved skb */
 420                 skb1 = skb_copy(forw_packet->skb, GFP_ATOMIC);
 421                 if (skb1)
 422                         send_skb_packet(skb1,
 423                                 batman_if, broadcastAddr);
 424         }
 425         rcu_read_unlock();
 426
 427         forw_packet->num_packets++;
 428
 429         /* if we still have some more bcasts to send and we are not shutting
 430          * down */
 431         if ((forw_packet->num_packets < 3) &&
 432             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 433                 _add_bcast_packet_to_list(forw_packet, ((5 * HZ) / 1000));
 434         else
 435                 forw_packet_free(forw_packet);
 436 }
 437
 438 void send_outstanding_bat_packet(struct work_struct *work)
 439 {
 440         struct delayed_work *delayed_work =
 441                 container_of(work, struct delayed_work, work);
 442         struct forw_packet *forw_packet =
 443                 container_of(delayed_work, struct forw_packet, delayed_work);
 444         unsigned long flags;
 445
 446         spin_lock_irqsave(&forw_bat_list_lock, flags);
 447         hlist_del(&forw_packet->list);
 448         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 449
 450         send_packet(forw_packet);
 451
 452         /**
 453          * we have to have at least one packet in the queue
 454          * to determine the queues wake up time unless we are
 455          * shutting down
 456          */
 457         if ((forw_packet->own) &&
 458             (atomic_read(&module_state) != MODULE_DEACTIVATING))
 459                 schedule_own_packet(forw_packet->if_incoming);
 460
 461         forw_packet_free(forw_packet);
 462 }
 463
 464 void purge_outstanding_packets(void)
 465 {
 466         struct forw_packet *forw_packet;
 467         struct hlist_node *tmp_node, *safe_tmp_node;
 468         unsigned long flags;
 469
 470         bat_dbg(DBG_BATMAN, "purge_outstanding_packets()\n");
 471
 472         /* free bcast list */
 473         spin_lock_irqsave(&forw_bcast_list_lock, flags);
 474         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 475                                   &forw_bcast_list, list) {
 476
 477                 spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 478
 479                 /**
 480                  * send_outstanding_bcast_packet() will lock the list to
 481                  * delete the item from the list
 482                  */
 483                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 484                 spin_lock_irqsave(&forw_bcast_list_lock, flags);
 485         }
 486         spin_unlock_irqrestore(&forw_bcast_list_lock, flags);
 487
 488         /* free batman packet list */
 489         spin_lock_irqsave(&forw_bat_list_lock, flags);
 490         hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
 491                                   &forw_bat_list, list) {
 492
 493                 spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 494
 495                 /**
 496                  * send_outstanding_bat_packet() will lock the list to
 497                  * delete the item from the list
 498                  */
 499                 cancel_delayed_work_sync(&forw_packet->delayed_work);
 500                 spin_lock_irqsave(&forw_bat_list_lock, flags);
 501         }
 502         spin_unlock_irqrestore(&forw_bat_list_lock, flags);
 503 }