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