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