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