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

   1 /*
   2     net_socket.c -- Handle various kinds of sockets.
   3     Copyright (C) 2014 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 "conf.h"
  23 #include "connection.h"
  24 #include "list.h"
  25 #include "logger.h"
  26 #include "meshlink_internal.h"
  27 #include "meta.h"
  28 #include "net.h"
  29 #include "netutl.h"
  30 #include "protocol.h"
  31 #include "utils.h"
  32 #include "xalloc.h"
  33
  34 /* Needed on Mac OS/X */
  35 #ifndef SOL_TCP
  36 #define SOL_TCP IPPROTO_TCP
  37 #endif
  38
  39 int addressfamily = AF_UNSPEC;
  40 int maxtimeout = 900;
  41 int seconds_till_retry = 5;
  42 int max_connection_burst = 100;
  43
  44 /* Setup sockets */
  45
  46 static void configure_tcp(connection_t *c) {
  47         int option;
  48
  49 #ifdef O_NONBLOCK
  50         int flags = fcntl(c->socket, F_GETFL);
  51
  52         if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
  53                 logger(DEBUG_ALWAYS, LOG_ERR, "fcntl for %s: %s", c->hostname, strerror(errno));
  54         }
  55 #elif defined(WIN32)
  56         unsigned long arg = 1;
  57
  58         if(ioctlsocket(c->socket, FIONBIO, &arg) != 0) {
  59                 logger(DEBUG_ALWAYS, LOG_ERR, "ioctlsocket for %s: %s", c->hostname, sockstrerror(sockerrno));
  60         }
  61 #endif
  62
  63 #if defined(SOL_TCP) && defined(TCP_NODELAY)
  64         option = 1;
  65         setsockopt(c->socket, SOL_TCP, TCP_NODELAY, (void *)&option, sizeof option);
  66 #endif
  67
  68 #if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
  69         option = IPTOS_LOWDELAY;
  70         setsockopt(c->socket, SOL_IP, IP_TOS, (void *)&option, sizeof option);
  71 #endif
  72 }
  73
  74 static bool bind_to_address(connection_t *c) {
  75         int s = -1;
  76
  77         for(int i = 0; i < mesh->listen_sockets && mesh->listen_socket[i].bindto; i++) {
  78                 if(mesh->listen_socket[i].sa.sa.sa_family != c->address.sa.sa_family)
  79                         continue;
  80                 if(s >= 0)
  81                         return false;
  82                 s = i;
  83         }
  84
  85         if(s < 0)
  86                 return false;
  87
  88         sockaddr_t sa = mesh->listen_socket[s].sa;
  89         if(sa.sa.sa_family == AF_INET)
  90                 sa.in.sin_port = 0;
  91         else if(sa.sa.sa_family == AF_INET6)
  92                 sa.in6.sin6_port = 0;
  93
  94         if(bind(c->socket, &sa.sa, SALEN(sa.sa))) {
  95                 logger(DEBUG_CONNECTIONS, LOG_WARNING, "Can't bind outgoing socket: %s", strerror(errno));
  96                 return false;
  97         }
  98
  99         return true;
 100 }
 101
 102 int setup_listen_socket(const sockaddr_t *sa) {
 103         int nfd;
 104         char *addrstr;
 105         int option;
 106         char *iface;
 107
 108         nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
 109
 110         if(nfd < 0) {
 111                 logger(DEBUG_STATUS, LOG_ERR, "Creating metasocket failed: %s", sockstrerror(sockerrno));
 112                 return -1;
 113         }
 114
 115 #ifdef FD_CLOEXEC
 116         fcntl(nfd, F_SETFD, FD_CLOEXEC);
 117 #endif
 118
 119         /* Optimize TCP settings */
 120
 121         option = 1;
 122         setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof option);
 123
 124 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
 125         if(sa->sa.sa_family == AF_INET6)
 126                 setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
 127 #endif
 128
 129         if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
 130                 closesocket(nfd);
 131                 addrstr = sockaddr2hostname(sa);
 132                 logger(DEBUG_ALWAYS, LOG_ERR, "Can't bind to %s/tcp: %s", addrstr, sockstrerror(sockerrno));
 133                 free(addrstr);
 134                 return -1;
 135         }
 136
 137         if(listen(nfd, 3)) {
 138                 closesocket(nfd);
 139                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno));
 140                 return -1;
 141         }
 142
 143         return nfd;
 144 }
 145
 146 int setup_vpn_in_socket(const sockaddr_t *sa) {
 147         int nfd;
 148         char *addrstr;
 149         int option;
 150
 151         nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
 152
 153         if(nfd < 0) {
 154                 logger(DEBUG_ALWAYS, LOG_ERR, "Creating UDP socket failed: %s", sockstrerror(sockerrno));
 155                 return -1;
 156         }
 157
 158 #ifdef FD_CLOEXEC
 159         fcntl(nfd, F_SETFD, FD_CLOEXEC);
 160 #endif
 161
 162 #ifdef O_NONBLOCK
 163         {
 164                 int flags = fcntl(nfd, F_GETFL);
 165
 166                 if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
 167                         closesocket(nfd);
 168                         logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "fcntl",
 169                                    strerror(errno));
 170                         return -1;
 171                 }
 172         }
 173 #elif defined(WIN32)
 174         {
 175                 unsigned long arg = 1;
 176                 if(ioctlsocket(nfd, FIONBIO, &arg) != 0) {
 177                         closesocket(nfd);
 178                         logger(DEBUG_ALWAYS, LOG_ERR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno));
 179                         return -1;
 180                 }
 181         }
 182 #endif
 183
 184         option = 1;
 185         setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof option);
 186         setsockopt(nfd, SOL_SOCKET, SO_BROADCAST, (void *)&option, sizeof option);
 187
 188 #if defined(IPPROTO_IPV6) && defined(IPV6_V6ONLY)
 189         if(sa->sa.sa_family == AF_INET6)
 190                 setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
 191 #endif
 192
 193 #if defined(IP_DONTFRAG) && !defined(IP_DONTFRAGMENT)
 194 #define IP_DONTFRAGMENT IP_DONTFRAG
 195 #endif
 196
 197 #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
 198         if(mesh->self->options & OPTION_PMTU_DISCOVERY) {
 199                 option = IP_PMTUDISC_DO;
 200                 setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option));
 201         }
 202 #elif defined(IPPROTO_IP) && defined(IP_DONTFRAGMENT)
 203         if(mesh->self->options & OPTION_PMTU_DISCOVERY) {
 204                 option = 1;
 205                 setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option));
 206         }
 207 #else
 208 #warning No way to disable IPv4 fragmentation
 209 #endif
 210
 211 #if defined(SOL_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
 212         if(mesh->self->options & OPTION_PMTU_DISCOVERY) {
 213                 option = IPV6_PMTUDISC_DO;
 214                 setsockopt(nfd, SOL_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option));
 215         }
 216 #elif defined(IPPROTO_IPV6) && defined(IPV6_DONTFRAG)
 217         if(mesh->self->options & OPTION_PMTU_DISCOVERY) {
 218                 option = 1;
 219                 setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option));
 220         }
 221 #else
 222 #warning No way to disable IPv6 fragmentation
 223 #endif
 224
 225         if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
 226                 closesocket(nfd);
 227                 addrstr = sockaddr2hostname(sa);
 228                 logger(DEBUG_ALWAYS, LOG_ERR, "Can't bind to %s/udp: %s", addrstr, sockstrerror(sockerrno));
 229                 free(addrstr);
 230                 return -1;
 231         }
 232
 233         return nfd;
 234 } /* int setup_vpn_in_socket */
 235
 236 static void retry_outgoing_handler(void *data) {
 237         setup_outgoing_connection(data);
 238 }
 239
 240 void retry_outgoing(outgoing_t *outgoing) {
 241         outgoing->timeout += 5;
 242
 243         if(outgoing->timeout > maxtimeout)
 244                 outgoing->timeout = maxtimeout;
 245
 246         timeout_add(&outgoing->ev, retry_outgoing_handler, outgoing, &(struct timeval){outgoing->timeout, rand() % 100000});
 247
 248         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Trying to re-establish outgoing connection in %d seconds", outgoing->timeout);
 249 }
 250
 251 void finish_connecting(connection_t *c) {
 252         logger(DEBUG_CONNECTIONS, LOG_INFO, "Connected to %s (%s)", c->name, c->hostname);
 253
 254         c->last_ping_time = now.tv_sec;
 255         c->status.connecting = false;
 256
 257         send_id(c);
 258 }
 259
 260 static void do_outgoing_pipe(connection_t *c, char *command) {
 261 #ifndef HAVE_MINGW
 262         int fd[2];
 263
 264         if(socketpair(AF_UNIX, SOCK_STREAM, 0, fd)) {
 265                 logger(DEBUG_ALWAYS, LOG_ERR, "Could not create socketpair: %s", strerror(errno));
 266                 return;
 267         }
 268
 269         if(fork()) {
 270                 c->socket = fd[0];
 271                 close(fd[1]);
 272                 logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Using proxy %s", command);
 273                 return;
 274         }
 275
 276         close(0);
 277         close(1);
 278         close(fd[0]);
 279         dup2(fd[1], 0);
 280         dup2(fd[1], 1);
 281         close(fd[1]);
 282
 283         // Other filedescriptors should be closed automatically by CLOEXEC
 284
 285         char *host = NULL;
 286         char *port = NULL;
 287
 288         sockaddr2str(&c->address, &host, &port);
 289         setenv("REMOTEADDRESS", host, true);
 290         setenv("REMOTEPORT", port, true);
 291         setenv("NODE", c->name, true);
 292         setenv("NAME", mesh->self->name, true);
 293
 294         int result = system(command);
 295         if(result < 0)
 296                 logger(DEBUG_ALWAYS, LOG_ERR, "Could not execute %s: %s", command, strerror(errno));
 297         else if(result)
 298                 logger(DEBUG_ALWAYS, LOG_ERR, "%s exited with non-zero status %d", command, result);
 299         exit(result);
 300 #else
 301         logger(DEBUG_ALWAYS, LOG_ERR, "Proxy type exec not supported on this platform!");
 302         return;
 303 #endif
 304 }
 305
 306 static void handle_meta_write(connection_t *c) {
 307         if(c->outbuf.len <= c->outbuf.offset)
 308                 return;
 309
 310         ssize_t outlen = send(c->socket, c->outbuf.data + c->outbuf.offset, c->outbuf.len - c->outbuf.offset, 0);
 311         if(outlen <= 0) {
 312                 if(!errno || errno == EPIPE) {
 313                         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection closed by %s (%s)", c->name, c->hostname);
 314                 } else if(sockwouldblock(sockerrno)) {
 315                         logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Sending %d bytes to %s (%s) would block", c->outbuf.len - c->outbuf.offset, c->name, c->hostname);
 316                         return;
 317                 } else {
 318                         logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not send %d bytes of data to %s (%s): %s", c->outbuf.len - c->outbuf.offset, c->name, c->hostname, strerror(errno));
 319                 }
 320
 321                 terminate_connection(c, c->status.active);
 322                 return;
 323         }
 324
 325         buffer_read(&c->outbuf, outlen);
 326         if(!c->outbuf.len)
 327                 io_set(&c->io, IO_READ);
 328 }
 329
 330 static void handle_meta_io(void *data, int flags) {
 331         connection_t *c = data;
 332
 333         if(c->status.connecting) {
 334                 c->status.connecting = false;
 335
 336                 int result;
 337                 socklen_t len = sizeof result;
 338                 getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len);
 339
 340                 if(!result)
 341                         finish_connecting(c);
 342                 else {
 343                         logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Error while connecting to %s (%s): %s", c->name, c->hostname, sockstrerror(result));
 344                         terminate_connection(c, false);
 345                         return;
 346                 }
 347         }
 348
 349         if(flags & IO_WRITE)
 350                 handle_meta_write(c);
 351         else
 352                 handle_meta_connection_data(c);
 353 }
 354
 355 bool do_outgoing_connection(outgoing_t *outgoing) {
 356         char *address, *port, *space;
 357         struct addrinfo *proxyai = NULL;
 358         int result;
 359
 360 begin:
 361         if(!outgoing->ai) {
 362                 if(!outgoing->cfg) {
 363                         logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not set up a meta connection to %s", outgoing->name);
 364                         retry_outgoing(outgoing);
 365                         return false;
 366                 }
 367
 368                 get_config_string(outgoing->cfg, &address);
 369
 370                 space = strchr(address, ' ');
 371                 if(space) {
 372                         port = xstrdup(space + 1);
 373                         *space = 0;
 374                 } else {
 375                         // TODO: Only allow Address statements?
 376                         if(!get_config_string(lookup_config(outgoing->config_tree, "Port"), &port))
 377                                 port = xstrdup("655");
 378                 }
 379
 380                 outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
 381                 free(address);
 382                 free(port);
 383
 384                 outgoing->aip = outgoing->ai;
 385                 outgoing->cfg = lookup_config_next(outgoing->config_tree, outgoing->cfg);
 386         }
 387
 388         if(!outgoing->aip) {
 389                 if(outgoing->ai)
 390                         freeaddrinfo(outgoing->ai);
 391                 outgoing->ai = NULL;
 392                 goto begin;
 393         }
 394
 395         connection_t *c = new_connection();
 396         c->outgoing = outgoing;
 397
 398         memcpy(&c->address, outgoing->aip->ai_addr, outgoing->aip->ai_addrlen);
 399         outgoing->aip = outgoing->aip->ai_next;
 400
 401         c->hostname = sockaddr2hostname(&c->address);
 402
 403         logger(DEBUG_CONNECTIONS, LOG_INFO, "Trying to connect to %s (%s)", outgoing->name, c->hostname);
 404
 405         if(!mesh->proxytype) {
 406                 c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
 407                 configure_tcp(c);
 408         } else if(mesh->proxytype == PROXY_EXEC) {
 409                 do_outgoing_pipe(c, mesh->proxyhost);
 410         } else {
 411                 proxyai = str2addrinfo(mesh->proxyhost, mesh->proxyport, SOCK_STREAM);
 412                 if(!proxyai) {
 413                         free_connection(c);
 414                         goto begin;
 415                 }
 416                 logger(DEBUG_CONNECTIONS, LOG_INFO, "Using proxy at %s port %s", mesh->proxyhost, mesh->proxyport);
 417                 c->socket = socket(proxyai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 418                 configure_tcp(c);
 419         }
 420
 421         if(c->socket == -1) {
 422                 logger(DEBUG_CONNECTIONS, LOG_ERR, "Creating socket for %s failed: %s", c->hostname, sockstrerror(sockerrno));
 423                 free_connection(c);
 424                 goto begin;
 425         }
 426
 427 #ifdef FD_CLOEXEC
 428         fcntl(c->socket, F_SETFD, FD_CLOEXEC);
 429 #endif
 430
 431         if(mesh->proxytype != PROXY_EXEC) {
 432 #if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
 433                 int option = 1;
 434                 if(c->address.sa.sa_family == AF_INET6)
 435                         setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
 436 #endif
 437
 438                 bind_to_address(c);
 439         }
 440
 441         /* Connect */
 442
 443         if(!mesh->proxytype) {
 444                 result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
 445         } else if(mesh->proxytype == PROXY_EXEC) {
 446                 result = 0;
 447         } else {
 448                 result = connect(c->socket, proxyai->ai_addr, proxyai->ai_addrlen);
 449                 freeaddrinfo(proxyai);
 450         }
 451
 452         if(result == -1 && !sockinprogress(sockerrno)) {
 453                 logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not connect to %s (%s): %s", outgoing->name, c->hostname, sockstrerror(sockerrno));
 454                 free_connection(c);
 455
 456                 goto begin;
 457         }
 458
 459         /* Now that there is a working socket, fill in the rest and register this connection. */
 460
 461         c->status.connecting = true;
 462         c->name = xstrdup(outgoing->name);
 463         c->outcompression = mesh->self->connection->outcompression;
 464         c->last_ping_time = now.tv_sec;
 465
 466         connection_add(c);
 467
 468         io_add(&c->io, handle_meta_io, c, c->socket, IO_READ|IO_WRITE);
 469
 470         return true;
 471 }
 472
 473 // Find edges pointing to this node, and use them to build a list of unique, known addresses.
 474 static struct addrinfo *get_known_addresses(node_t *n) {
 475         struct addrinfo *ai = NULL;
 476
 477         for splay_each(edge_t, e, n->edge_tree) {
 478                 if(!e->reverse)
 479                         continue;
 480
 481                 bool found = false;
 482                 for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
 483                         if(!sockaddrcmp(&e->reverse->address, (sockaddr_t *)aip->ai_addr)) {
 484                                 found = true;
 485                                 break;
 486                         }
 487                 }
 488                 if(found)
 489                         continue;
 490
 491                 struct addrinfo *nai = xzalloc(sizeof *nai);
 492                 if(ai)
 493                         ai->ai_next = nai;
 494                 ai = nai;
 495                 ai->ai_family = e->reverse->address.sa.sa_family;
 496                 ai->ai_socktype = SOCK_STREAM;
 497                 ai->ai_protocol = IPPROTO_TCP;
 498                 ai->ai_addrlen = SALEN(e->reverse->address.sa);
 499                 ai->ai_addr = xmalloc(ai->ai_addrlen);
 500                 memcpy(ai->ai_addr, &e->reverse->address, ai->ai_addrlen);
 501         }
 502
 503         return ai;
 504 }
 505
 506 void setup_outgoing_connection(outgoing_t *outgoing) {
 507         timeout_del(&outgoing->ev);
 508
 509         node_t *n = lookup_node(outgoing->name);
 510
 511         if(n && n->connection) {
 512                 logger(DEBUG_CONNECTIONS, LOG_INFO, "Already connected to %s", outgoing->name);
 513
 514                 n->connection->outgoing = outgoing;
 515                 return;
 516         }
 517
 518         init_configuration(&outgoing->config_tree);
 519         read_host_config(outgoing->config_tree, outgoing->name);
 520         outgoing->cfg = lookup_config(outgoing->config_tree, "Address");
 521
 522         if(!outgoing->cfg) {
 523                 if(n)
 524                         outgoing->aip = outgoing->ai = get_known_addresses(n);
 525                 if(!outgoing->ai) {
 526                         logger(DEBUG_ALWAYS, LOG_ERR, "No address known for %s", outgoing->name);
 527                         return;
 528                 }
 529         }
 530
 531         do_outgoing_connection(outgoing);
 532 }
 533
 534 /*
 535   accept a new tcp connect and create a
 536   new connection
 537 */
 538 void handle_new_meta_connection(void *data, int flags) {
 539         listen_socket_t *l = data;
 540         connection_t *c;
 541         sockaddr_t sa;
 542         int fd;
 543         socklen_t len = sizeof sa;
 544
 545         fd = accept(l->tcp.fd, &sa.sa, &len);
 546
 547         if(fd < 0) {
 548                 logger(DEBUG_ALWAYS, LOG_ERR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
 549                 return;
 550         }
 551
 552         sockaddrunmap(&sa);
 553
 554         // Check if we get many connections from the same host
 555
 556         static sockaddr_t prev_sa;
 557         static int tarpit = -1;
 558
 559         if(tarpit >= 0) {
 560                 closesocket(tarpit);
 561                 tarpit = -1;
 562         }
 563
 564         if(!sockaddrcmp_noport(&sa, &prev_sa)) {
 565                 static int samehost_burst;
 566                 static int samehost_burst_time;
 567
 568                 if(now.tv_sec - samehost_burst_time > samehost_burst)
 569                         samehost_burst = 0;
 570                 else
 571                         samehost_burst -= now.tv_sec - samehost_burst_time;
 572
 573                 samehost_burst_time = now.tv_sec;
 574                 samehost_burst++;
 575
 576                 if(samehost_burst > max_connection_burst) {
 577                         tarpit = fd;
 578                         return;
 579                 }
 580         }
 581
 582         memcpy(&prev_sa, &sa, sizeof sa);
 583
 584         // Check if we get many connections from different hosts
 585
 586         static int connection_burst;
 587         static int connection_burst_time;
 588
 589         if(now.tv_sec - connection_burst_time > connection_burst)
 590                 connection_burst = 0;
 591         else
 592                 connection_burst -= now.tv_sec - connection_burst_time;
 593
 594         connection_burst_time = now.tv_sec;
 595         connection_burst++;
 596
 597         if(connection_burst >= max_connection_burst) {
 598                 connection_burst = max_connection_burst;
 599                 tarpit = fd;
 600                 return;
 601         }
 602
 603         // Accept the new connection
 604
 605         c = new_connection();
 606         c->name = xstrdup("<unknown>");
 607         c->outcompression = mesh->self->connection->outcompression;
 608
 609         c->address = sa;
 610         c->hostname = sockaddr2hostname(&sa);
 611         c->socket = fd;
 612         c->last_ping_time = now.tv_sec;
 613
 614         logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection from %s", c->hostname);
 615
 616         io_add(&c->io, handle_meta_io, c, c->socket, IO_READ);
 617
 618         configure_tcp(c);
 619
 620         connection_add(c);
 621
 622         c->allow_request = ID;
 623         send_id(c);
 624 }
 625
 626 static void free_outgoing(outgoing_t *outgoing) {
 627         timeout_del(&outgoing->ev);
 628
 629         if(outgoing->ai)
 630                 freeaddrinfo(outgoing->ai);
 631
 632         if(outgoing->config_tree)
 633                 exit_configuration(&outgoing->config_tree);
 634
 635         if(outgoing->name)
 636                 free(outgoing->name);
 637
 638         free(outgoing);
 639 }
 640
 641 void try_outgoing_connections(void) {
 642         /* If there is no outgoing list yet, create one. Otherwise, mark all outgoings as deleted. */
 643
 644         if(!mesh->outgoings) {
 645                 mesh->outgoings = list_alloc((list_action_t)free_outgoing);
 646         } else {
 647                 for list_each(outgoing_t, outgoing, mesh->outgoings)
 648                         outgoing->timeout = -1;
 649         }
 650
 651         /* Make sure there is one outgoing_t in the list for each ConnectTo. */
 652
 653         // TODO: Drop support for ConnectTo since AutoConnect is now always on?
 654         for(config_t *cfg = lookup_config(mesh->config, "ConnectTo"); cfg; cfg = lookup_config_next(mesh->config, cfg)) {
 655                 char *name;
 656                 get_config_string(cfg, &name);
 657
 658                 if(!check_id(name)) {
 659                         logger(DEBUG_ALWAYS, LOG_ERR,
 660                                    "Invalid name for outgoing connection in %s line %d",
 661                                    cfg->file, cfg->line);
 662                         free(name);
 663                         continue;
 664                 }
 665
 666                 bool found = false;
 667
 668                 for list_each(outgoing_t, outgoing, mesh->outgoings) {
 669                         if(!strcmp(outgoing->name, name)) {
 670                                 found = true;
 671                                 outgoing->timeout = 0;
 672                                 break;
 673                         }
 674                 }
 675
 676                 if(!found) {
 677                         outgoing_t *outgoing = xzalloc(sizeof *outgoing);
 678                         outgoing->name = name;
 679                         list_insert_tail(mesh->outgoings, outgoing);
 680                         setup_outgoing_connection(outgoing);
 681                 }
 682         }
 683
 684         /* Terminate any connections whose outgoing_t is to be deleted. */
 685
 686         for list_each(connection_t, c, mesh->connections) {
 687                 if(c->outgoing && c->outgoing->timeout == -1) {
 688                         c->outgoing = NULL;
 689                         logger(DEBUG_CONNECTIONS, LOG_INFO, "No more outgoing connection to %s", c->name);
 690                         terminate_connection(c, c->status.active);
 691                 }
 692         }
 693
 694         /* Delete outgoing_ts for which there is no ConnectTo. */
 695
 696         for list_each(outgoing_t, outgoing, mesh->outgoings)
 697                 if(outgoing->timeout == -1)
 698                         list_delete_node(mesh->outgoings, node);
 699 }