git.meshlink.io Git - meshlink/blob - src/net.c

   1 /*
   2     net.c -- most of the network code
   3     Copyright (C) 2014-2017 Guus Sliepen <guus@meshlink.io>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License along
  16     with this program; if not, write to the Free Software Foundation, Inc.,
  17     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "system.h"
  21
  22 #include "utils.h"
  23 #include "conf.h"
  24 #include "connection.h"
  25 #include "devtools.h"
  26 #include "graph.h"
  27 #include "logger.h"
  28 #include "meshlink_internal.h"
  29 #include "meta.h"
  30 #include "net.h"
  31 #include "netutl.h"
  32 #include "pmtu.h"
  33 #include "protocol.h"
  34 #include "sptps.h"
  35 #include "xalloc.h"
  36
  37 #include <assert.h>
  38
  39 #if !defined(min)
  40 static inline int min(int a, int b) {
  41         return a < b ? a : b;
  42 }
  43 #endif
  44
  45 static const int default_timeout = 5;
  46 static const int default_interval = 60;
  47
  48 /*
  49   Terminate a connection:
  50   - Mark it as inactive
  51   - Remove the edge representing this connection
  52   - Kill it with fire
  53   - Check if we need to retry making an outgoing connection
  54 */
  55 void terminate_connection(meshlink_handle_t *mesh, connection_t *c, bool report) {
  56         if(c->status.active) {
  57                 logger(mesh, MESHLINK_INFO, "Closing connection with %s", c->name);
  58         }
  59
  60         if(c->node && c->node->connection == c) {
  61                 if(c->status.active && mesh->meta_status_cb) {
  62                         mesh->meta_status_cb(mesh, (meshlink_node_t *)c->node, false);
  63                 }
  64
  65                 c->node->connection = NULL;
  66         }
  67
  68         c->status.active = false;
  69
  70         if(c->edge) {
  71                 if(report) {
  72                         send_del_edge(mesh, mesh->everyone, c->edge, 0);
  73                 }
  74
  75                 edge_del(mesh, c->edge);
  76                 c->edge = NULL;
  77
  78                 /* Run MST and SSSP algorithms */
  79
  80                 graph(mesh);
  81
  82                 /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */
  83
  84                 if(report && c->node && !c->node->status.reachable) {
  85                         edge_t *e;
  86                         e = lookup_edge(c->node, mesh->self);
  87
  88                         if(e) {
  89                                 send_del_edge(mesh, mesh->everyone, e, 0);
  90                                 edge_del(mesh, e);
  91                         }
  92                 }
  93         }
  94
  95         outgoing_t *outgoing = c->outgoing;
  96         connection_del(mesh, c);
  97
  98         /* Check if this was our outgoing connection */
  99
 100         if(outgoing) {
 101                 do_outgoing_connection(mesh, outgoing);
 102         }
 103 }
 104
 105 /*
 106   Check if the other end is active.
 107   If we have sent packets, but didn't receive any,
 108   then possibly the other end is dead. We send a
 109   PING request over the meta connection. If the other
 110   end does not reply in time, we consider them dead
 111   and close the connection.
 112 */
 113 static void timeout_handler(event_loop_t *loop, void *data) {
 114         assert(data);
 115
 116         meshlink_handle_t *mesh = loop->data;
 117         logger(mesh, MESHLINK_DEBUG, "timeout_handler()");
 118
 119         for list_each(connection_t, c, mesh->connections) {
 120                 int pingtimeout = c->node ? mesh->dev_class_traits[c->node->devclass].pingtimeout : default_timeout;
 121                 int pinginterval = c->node ? mesh->dev_class_traits[c->node->devclass].pinginterval : default_interval;
 122
 123                 if(c->outgoing && !c->status.active && c->outgoing->timeout < 5) {
 124                         pingtimeout = 1;
 125                 }
 126
 127                 // Also make sure that if outstanding key requests for the UDP counterpart of a connection has timed out, we restart it.
 128                 if(c->node) {
 129                         if(c->node->status.waitingforkey && c->node->last_req_key + pingtimeout < mesh->loop.now.tv_sec) {
 130                                 send_req_key(mesh, c->node);
 131                         }
 132
 133                         keepalive(mesh, c->node, false);
 134                 }
 135
 136                 if(c->status.active && c->last_key_renewal + 3600 < mesh->loop.now.tv_sec) {
 137                         devtool_sptps_renewal_probe((meshlink_node_t *)c->node);
 138
 139                         if(!sptps_force_kex(&c->sptps)) {
 140                                 logger(mesh, MESHLINK_ERROR, "SPTPS key renewal for connection with %s failed", c->name);
 141                                 terminate_connection(mesh, c, true);
 142                                 continue;
 143                         } else {
 144                                 c->last_key_renewal = mesh->loop.now.tv_sec;
 145                         }
 146                 }
 147
 148                 if(c->last_ping_time + pingtimeout < mesh->loop.now.tv_sec) {
 149                         if(c->status.active) {
 150                                 if(c->status.pinged) {
 151                                         logger(mesh, MESHLINK_INFO, "%s didn't respond to PING in %ld seconds", c->name, (long)mesh->loop.now.tv_sec - c->last_ping_time);
 152                                 } else if(c->last_ping_time + pinginterval <= mesh->loop.now.tv_sec) {
 153                                         send_ping(mesh, c);
 154                                         continue;
 155                                 } else {
 156                                         continue;
 157                                 }
 158                         } else {
 159                                 if(c->status.connecting) {
 160                                         logger(mesh, MESHLINK_WARNING, "Timeout while connecting to %s", c->name);
 161                                 } else {
 162                                         logger(mesh, MESHLINK_WARNING, "Timeout from %s during authentication", c->name);
 163                                 }
 164                         }
 165
 166                         terminate_connection(mesh, c, c->status.active);
 167                         continue;
 168                 }
 169         }
 170
 171         timeout_set(&mesh->loop, data, &(struct timespec) {
 172                 1, prng(mesh, TIMER_FUDGE)
 173         });
 174 }
 175
 176 // devclass asc, last_successfull_connection desc
 177 static int node_compare_devclass_asc_lsc_desc(const void *a, const void *b) {
 178         const node_t *na = a, *nb = b;
 179
 180         if(na->devclass < nb->devclass) {
 181                 return -1;
 182         }
 183
 184         if(na->devclass > nb->devclass) {
 185                 return 1;
 186         }
 187
 188         if(na->last_successfull_connection == nb->last_successfull_connection) {
 189                 return 0;
 190         }
 191
 192         if(na->last_successfull_connection == 0 || na->last_successfull_connection > nb->last_successfull_connection) {
 193                 return -1;
 194         }
 195
 196         if(nb->last_successfull_connection == 0 || na->last_successfull_connection < nb->last_successfull_connection) {
 197                 return 1;
 198         }
 199
 200         if(na < nb) {
 201                 return -1;
 202         }
 203
 204         if(na > nb) {
 205                 return 1;
 206         }
 207
 208         return 0;
 209 }
 210
 211 // last_successfull_connection desc
 212 static int node_compare_lsc_desc(const void *a, const void *b) {
 213         const node_t *na = a, *nb = b;
 214
 215         if(na->last_successfull_connection == nb->last_successfull_connection) {
 216                 return 0;
 217         }
 218
 219         if(na->last_successfull_connection == 0 || na->last_successfull_connection > nb->last_successfull_connection) {
 220                 return -1;
 221         }
 222
 223         if(nb->last_successfull_connection == 0 || na->last_successfull_connection < nb->last_successfull_connection) {
 224                 return 1;
 225         }
 226
 227         if(na < nb) {
 228                 return -1;
 229         }
 230
 231         if(na > nb) {
 232                 return 1;
 233         }
 234
 235         return 0;
 236 }
 237
 238 // devclass desc
 239 static int node_compare_devclass_desc(const void *a, const void *b) {
 240         const node_t *na = a, *nb = b;
 241
 242         if(na->devclass < nb->devclass) {
 243                 return -1;
 244         }
 245
 246         if(na->devclass > nb->devclass) {
 247                 return 1;
 248         }
 249
 250         if(na < nb) {
 251                 return -1;
 252         }
 253
 254         if(na > nb) {
 255                 return 1;
 256         }
 257
 258         return 0;
 259 }
 260
 261
 262 /*
 263
 264 autoconnect()
 265 {
 266         timeout = 5
 267
 268         // find the best one for initial connect
 269
 270         if cur < min
 271                 newcon =
 272                         first from nodes
 273                                 where dclass <= my.dclass and !connection and (timestamp - last_retry) > retry_timeout
 274                                 order by dclass asc, last_connection desc
 275                 if newcon
 276                         timeout = 0
 277                         goto connect
 278
 279
 280         // find better nodes to connect to: in case we have less than min connections within [BACKBONE, i] and there are nodes which we are not connected to within the range
 281
 282         if min <= cur < max
 283                 j = 0
 284                 for i = BACKBONE to my.dclass
 285                         j += count(from connections where node.dclass = i)
 286                         if j < min
 287                                 newcon =
 288                                         first from nodes
 289                                                 where dclass = i and !connection and (timestamp - last_retry) > retry_timeout
 290                                                 order by last_connection desc
 291                                 if newcon
 292                                         goto connect
 293                         else
 294                                 break
 295
 296
 297         // heal partitions
 298
 299         if min <= cur < max
 300                 newcon =
 301                         first from nodes
 302                                 where dclass <= my.dclass and !reachable and (timestamp - last_retry) > retry_timeout
 303                                 order by dclass asc, last_connection desc
 304                 if newcon
 305                         goto connect
 306
 307
 308         // connect
 309
 310 connect:
 311         if newcon
 312                 connect newcon
 313
 314
 315         // disconnect outgoing connections in case we have more than min connections within [BACKBONE, i] and there are nodes which we are connected to within the range [i, PORTABLE]
 316
 317         if min < cur <= max
 318                 j = 0
 319                 for i = BACKBONE to my.dclass
 320                         j += count(from connections where node.dclass = i)
 321                         if min < j
 322                                 delcon =
 323                                         first from nodes
 324                                                 where dclass >= i and outgoing_connection
 325                                                 order by dclass desc
 326                                 if disconnect
 327                                         goto disconnect
 328                                 else
 329                                         break
 330
 331
 332         // disconnect connections in case we have more than enough connections
 333
 334         if max < cur
 335                 delcon =
 336                         first from nodes
 337                                 where outgoing_connection
 338                                 order by dclass desc
 339                 goto disconnect
 340
 341         // disconnect
 342
 343 disconnect
 344         if delcon
 345                 disconnect delcon
 346
 347
 348         // next iteration
 349         next (timeout, autoconnect)
 350
 351 }
 352
 353 */
 354
 355
 356 static void periodic_handler(event_loop_t *loop, void *data) {
 357         meshlink_handle_t *mesh = loop->data;
 358
 359         /* Check if there are too many contradicting ADD_EDGE and DEL_EDGE messages.
 360            This usually only happens when another node has the same Name as this node.
 361            If so, sleep for a short while to prevent a storm of contradicting messages.
 362         */
 363
 364         if(mesh->contradicting_del_edge > 100 && mesh->contradicting_add_edge > 100) {
 365                 logger(mesh, MESHLINK_WARNING, "Possible node with same Name as us! Sleeping %d seconds.", mesh->sleeptime);
 366                 struct timespec ts = {mesh->sleeptime, 0};
 367                 nanosleep(&ts, NULL);
 368                 mesh->sleeptime *= 2;
 369
 370                 if(mesh->sleeptime < 0) {
 371                         mesh->sleeptime = 3600;
 372                 }
 373         } else {
 374                 mesh->sleeptime /= 2;
 375
 376                 if(mesh->sleeptime < 10) {
 377                         mesh->sleeptime = 10;
 378                 }
 379         }
 380
 381         mesh->contradicting_add_edge = 0;
 382         mesh->contradicting_del_edge = 0;
 383
 384         int timeout = default_timeout;
 385
 386         /* Check if we need to make or break connections. */
 387
 388         if(mesh->nodes->count > 1) {
 389
 390                 logger(mesh, MESHLINK_DEBUG, "--- autoconnect begin ---");
 391
 392                 int retry_timeout = min(mesh->nodes->count * default_timeout, 60);
 393
 394                 logger(mesh, MESHLINK_DEBUG, "* devclass = %d", mesh->devclass);
 395                 logger(mesh, MESHLINK_DEBUG, "* nodes = %d", mesh->nodes->count);
 396                 logger(mesh, MESHLINK_DEBUG, "* retry_timeout = %d", retry_timeout);
 397
 398
 399                 // connect disconnect nodes
 400
 401                 node_t *connect_to = NULL;
 402                 node_t *disconnect_from = NULL;
 403
 404
 405                 // get cur_connects
 406
 407                 unsigned int cur_connects = 0;
 408
 409                 for list_each(connection_t, c, mesh->connections) {
 410                         if(c->status.active) {
 411                                 cur_connects += 1;
 412                         }
 413                 }
 414
 415                 logger(mesh, MESHLINK_DEBUG, "* cur_connects = %d", cur_connects);
 416                 logger(mesh, MESHLINK_DEBUG, "* outgoings = %d", mesh->outgoings->count);
 417
 418                 // get min_connects and max_connects
 419
 420                 unsigned int min_connects = mesh->dev_class_traits[mesh->devclass].min_connects;
 421                 unsigned int max_connects = mesh->dev_class_traits[mesh->devclass].max_connects;
 422
 423                 logger(mesh, MESHLINK_DEBUG, "* min_connects = %d", min_connects);
 424                 logger(mesh, MESHLINK_DEBUG, "* max_connects = %d", max_connects);
 425
 426                 // find the best one for initial connect
 427
 428                 if(cur_connects < min_connects) {
 429                         splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_asc_lsc_desc, NULL);
 430
 431                         for splay_each(node_t, n, mesh->nodes) {
 432                                 logger(mesh, MESHLINK_DEBUG, "* %s->devclass = %d", n->name, n->devclass);
 433
 434                                 if(n != mesh->self && n->devclass <= mesh->devclass && !n->connection && !n->status.blacklisted && (n->last_connect_try == 0 || (mesh->loop.now.tv_sec - n->last_connect_try) > retry_timeout)) {
 435                                         splay_insert(nodes, n);
 436                                 }
 437                         }
 438
 439                         if(nodes->head) {
 440                                 //timeout = 0;
 441                                 connect_to = (node_t *)nodes->head->data;
 442
 443                                 logger(mesh, MESHLINK_DEBUG, "* found best one for initial connect: %s", connect_to->name);
 444                         } else {
 445                                 logger(mesh, MESHLINK_DEBUG, "* could not find node for initial connect");
 446                         }
 447
 448                         splay_delete_tree(nodes);
 449                 }
 450
 451
 452                 // find better nodes to connect to
 453
 454                 if(!connect_to && min_connects <= cur_connects && cur_connects < max_connects) {
 455                         unsigned int connects = 0;
 456
 457                         for(dev_class_t devclass = 0; devclass <= mesh->devclass; ++devclass) {
 458                                 for list_each(connection_t, c, mesh->connections) {
 459                                         if(c->status.active && c->node && c->node->devclass == devclass) {
 460                                                 connects += 1;
 461                                         }
 462                                 }
 463
 464                                 if(connects < min_connects) {
 465                                         splay_tree_t *nodes = splay_alloc_tree(node_compare_lsc_desc, NULL);
 466
 467                                         for splay_each(node_t, n, mesh->nodes) {
 468                                                 if(n != mesh->self && n->devclass == devclass && !n->connection && !n->status.blacklisted && (n->last_connect_try == 0 || (mesh->loop.now.tv_sec - n->last_connect_try) > retry_timeout)) {
 469                                                         splay_insert(nodes, n);
 470                                                 }
 471                                         }
 472
 473                                         if(nodes->head) {
 474                                                 logger(mesh, MESHLINK_DEBUG, "* found better node");
 475                                                 connect_to = (node_t *)nodes->head->data;
 476
 477                                                 splay_delete_tree(nodes);
 478                                                 break;
 479                                         }
 480
 481                                         splay_delete_tree(nodes);
 482                                 } else {
 483                                         break;
 484                                 }
 485                         }
 486
 487                         if(!connect_to) {
 488                                 logger(mesh, MESHLINK_DEBUG, "* could not find better nodes");
 489                         }
 490                 }
 491
 492
 493                 // heal partitions
 494
 495                 if(!connect_to && min_connects <= cur_connects && cur_connects < max_connects) {
 496                         splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_asc_lsc_desc, NULL);
 497
 498                         for splay_each(node_t, n, mesh->nodes) {
 499                                 if(n != mesh->self && n->devclass <= mesh->devclass && !n->status.reachable && !n->status.blacklisted && (n->last_connect_try == 0 || (mesh->loop.now.tv_sec - n->last_connect_try) > retry_timeout)) {
 500                                         splay_insert(nodes, n);
 501                                 }
 502                         }
 503
 504                         if(nodes->head) {
 505                                 logger(mesh, MESHLINK_DEBUG, "* try to heal partition");
 506                                 connect_to = (node_t *)nodes->head->data;
 507                         } else {
 508                                 logger(mesh, MESHLINK_DEBUG, "* could not find nodes for partition healing");
 509                         }
 510
 511                         splay_delete_tree(nodes);
 512                 }
 513
 514
 515                 // perform connect
 516
 517                 if(connect_to && !connect_to->connection) {
 518                         connect_to->last_connect_try = mesh->loop.now.tv_sec;
 519                         logger(mesh, MESHLINK_DEBUG, "Autoconnect trying to connect to %s", connect_to->name);
 520
 521                         /* check if there is already a connection attempt to this node */
 522                         bool skip = false;
 523
 524                         for list_each(outgoing_t, outgoing, mesh->outgoings) {
 525                                 if(outgoing->node == connect_to) {
 526                                         logger(mesh, MESHLINK_DEBUG, "* skip autoconnect since it is an outgoing connection already");
 527                                         skip = true;
 528                                         break;
 529                                 }
 530                         }
 531
 532                         if(!connect_to->status.reachable && !node_read_public_key(mesh, connect_to)) {
 533                                 logger(mesh, MESHLINK_DEBUG, "* skip autoconnect since we don't know this node's public key");
 534                                 skip = true;
 535                         }
 536
 537                         if(!skip) {
 538                                 logger(mesh, MESHLINK_DEBUG, "Autoconnecting to %s", connect_to->name);
 539                                 outgoing_t *outgoing = xzalloc(sizeof(outgoing_t));
 540                                 outgoing->node = connect_to;
 541                                 list_insert_tail(mesh->outgoings, outgoing);
 542                                 setup_outgoing_connection(mesh, outgoing);
 543                         }
 544                 }
 545
 546
 547                 // disconnect suboptimal outgoing connections
 548
 549                 if(min_connects < cur_connects /*&& cur_connects <= max_connects*/) {
 550                         unsigned int connects = 0;
 551
 552                         for(dev_class_t devclass = 0; devclass <= mesh->devclass; ++devclass) {
 553                                 for list_each(connection_t, c, mesh->connections) {
 554                                         if(c->status.active && c->node && c->node->devclass == devclass) {
 555                                                 connects += 1;
 556                                         }
 557                                 }
 558
 559                                 if(min_connects < connects) {
 560                                         splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_desc, NULL);
 561
 562                                         for list_each(connection_t, c, mesh->connections) {
 563                                                 if(c->outgoing && c->node && c->node->devclass >= devclass) {
 564                                                         splay_insert(nodes, c->node);
 565                                                 }
 566                                         }
 567
 568                                         if(nodes->head) {
 569                                                 logger(mesh, MESHLINK_DEBUG, "* disconnect suboptimal outgoing connection");
 570                                                 disconnect_from = (node_t *)nodes->head->data;
 571                                         }
 572
 573                                         splay_delete_tree(nodes);
 574                                         break;
 575                                 }
 576                         }
 577
 578                         if(!disconnect_from) {
 579                                 logger(mesh, MESHLINK_DEBUG, "* no suboptimal outgoing connections");
 580                         }
 581                 }
 582
 583
 584                 // disconnect connections (too many connections)
 585
 586                 if(!disconnect_from && max_connects < cur_connects) {
 587                         splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_desc, NULL);
 588
 589                         for list_each(connection_t, c, mesh->connections) {
 590                                 if(c->status.active && c->node) {
 591                                         splay_insert(nodes, c->node);
 592                                 }
 593                         }
 594
 595                         if(nodes->head) {
 596                                 logger(mesh, MESHLINK_DEBUG, "* disconnect connection (too many connections)");
 597
 598                                 //timeout = 0;
 599                                 disconnect_from = (node_t *)nodes->head->data;
 600                         } else {
 601                                 logger(mesh, MESHLINK_DEBUG, "* no node we want to disconnect, even though we have too many connections");
 602                         }
 603
 604                         splay_delete_tree(nodes);
 605                 }
 606
 607
 608                 // perform disconnect
 609
 610                 if(disconnect_from && disconnect_from->connection) {
 611                         logger(mesh, MESHLINK_DEBUG, "Autodisconnecting from %s", disconnect_from->connection->name);
 612                         list_delete(mesh->outgoings, disconnect_from->connection->outgoing);
 613                         disconnect_from->connection->outgoing = NULL;
 614                         terminate_connection(mesh, disconnect_from->connection, disconnect_from->connection->status.active);
 615                 }
 616
 617                 // reduce timeout if we don't have enough connections + outgoings
 618                 if(cur_connects + mesh->outgoings->count < 3) {
 619                         timeout = 1;
 620                 }
 621
 622                 // done!
 623
 624                 logger(mesh, MESHLINK_DEBUG, "--- autoconnect end ---");
 625         }
 626
 627         for splay_each(node_t, n, mesh->nodes) {
 628                 if(n->status.dirty) {
 629                         if(!node_write_config(mesh, n, false)) {
 630                                 logger(mesh, MESHLINK_DEBUG, "Could not update %s", n->name);
 631                         }
 632                 }
 633
 634                 if(n->status.reachable && n->status.validkey && n->last_req_key + 3600 < mesh->loop.now.tv_sec) {
 635                         logger(mesh, MESHLINK_DEBUG, "SPTPS key renewal for node %s", n->name);
 636                         devtool_sptps_renewal_probe((meshlink_node_t *)n);
 637
 638                         if(!sptps_force_kex(&n->sptps)) {
 639                                 logger(mesh, MESHLINK_ERROR, "SPTPS key renewal for node %s failed", n->name);
 640                                 n->status.validkey = false;
 641                                 sptps_stop(&n->sptps);
 642                                 n->status.waitingforkey = false;
 643                                 n->last_req_key = -3600;
 644                         } else {
 645                                 n->last_req_key = mesh->loop.now.tv_sec;
 646                         }
 647                 }
 648         }
 649
 650         timeout_set(&mesh->loop, data, &(struct timespec) {
 651                 timeout, prng(mesh, TIMER_FUDGE)
 652         });
 653 }
 654
 655 void handle_meta_connection_data(meshlink_handle_t *mesh, connection_t *c) {
 656         if(!receive_meta(mesh, c)) {
 657                 terminate_connection(mesh, c, c->status.active);
 658                 return;
 659         }
 660 }
 661
 662 void retry(meshlink_handle_t *mesh) {
 663         /* Reset the reconnection timers for all outgoing connections */
 664         for list_each(outgoing_t, outgoing, mesh->outgoings) {
 665                 outgoing->timeout = 0;
 666
 667                 if(outgoing->ev.cb) {
 668                         timeout_set(&mesh->loop, &outgoing->ev, &(struct timespec) {
 669                                 0, 0
 670                         });
 671                 }
 672         }
 673
 674         /* For active connections, check if their addresses are still valid.
 675          * If yes, reset their ping timers, otherwise terminate them. */
 676         for list_each(connection_t, c, mesh->connections) {
 677                 if(!c->status.active) {
 678                         continue;
 679                 }
 680
 681                 if(!c->status.pinged) {
 682                         c->last_ping_time = -3600;
 683                 }
 684
 685                 sockaddr_t sa;
 686                 socklen_t salen = sizeof(sa);
 687
 688                 if(getsockname(c->socket, &sa.sa, &salen)) {
 689                         continue;
 690                 }
 691
 692                 switch(sa.sa.sa_family) {
 693                 case AF_INET:
 694                         sa.in.sin_port = 0;
 695                         break;
 696
 697                 case AF_INET6:
 698                         sa.in6.sin6_port = 0;
 699                         break;
 700
 701                 default:
 702                         continue;
 703                 }
 704
 705                 int sock = socket(sa.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
 706
 707                 if(sock == -1) {
 708                         continue;
 709                 }
 710
 711                 if(bind(sock, &sa.sa, salen) && errno == EADDRNOTAVAIL) {
 712                         logger(mesh, MESHLINK_DEBUG, "Local address for connection to %s no longer valid, terminating", c->name);
 713                         terminate_connection(mesh, c, c->status.active);
 714                 }
 715
 716                 closesocket(sock);
 717         }
 718
 719         /* Kick the ping timeout handler */
 720         if(mesh->pingtimer.cb) {
 721                 timeout_set(&mesh->loop, &mesh->pingtimer, &(struct timespec) {
 722                         0, 0
 723                 });
 724         }
 725 }
 726
 727 /*
 728   this is where it all happens...
 729 */
 730 void main_loop(meshlink_handle_t *mesh) {
 731         timeout_add(&mesh->loop, &mesh->pingtimer, timeout_handler, &mesh->pingtimer, &(struct timespec) {
 732                 1, prng(mesh, TIMER_FUDGE)
 733         });
 734         timeout_add(&mesh->loop, &mesh->periodictimer, periodic_handler, &mesh->periodictimer, &(struct timespec) {
 735                 0, 0
 736         });
 737
 738         //Add signal handler
 739         mesh->datafromapp.signum = 0;
 740         signal_add(&mesh->loop, &mesh->datafromapp, meshlink_send_from_queue, mesh, mesh->datafromapp.signum);
 741
 742         if(!event_loop_run(&mesh->loop, mesh)) {
 743                 logger(mesh, MESHLINK_ERROR, "Error while waiting for input: %s", strerror(errno));
 744                 call_error_cb(mesh, MESHLINK_ENETWORK);
 745         }
 746
 747         signal_del(&mesh->loop, &mesh->datafromapp);
 748         timeout_del(&mesh->loop, &mesh->periodictimer);
 749         timeout_del(&mesh->loop, &mesh->pingtimer);
 750 }