Nexthop calculation should always use the shortest path.
[tinc] / src / net_setup.c
1 /*
2     net_setup.c -- Setup.
3     Copyright (C) 1998-2005 Ivo Timmermans,
4                   2000-2013 Guus Sliepen <guus@tinc-vpn.org>
5                   2006      Scott Lamb <slamb@slamb.org>
6                   2010      Brandon Black <blblack@gmail.com>
7
8     This program is free software; you can redistribute it and/or modify
9     it under the terms of the GNU General Public License as published by
10     the Free Software Foundation; either version 2 of the License, or
11     (at your option) any later version.
12
13     This program is distributed in the hope that it will be useful,
14     but WITHOUT ANY WARRANTY; without even the implied warranty of
15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16     GNU General Public License for more details.
17
18     You should have received a copy of the GNU General Public License along
19     with this program; if not, write to the Free Software Foundation, Inc.,
20     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 */
22
23 #include "system.h"
24
25 #include <openssl/pem.h>
26 #include <openssl/rsa.h>
27 #include <openssl/rand.h>
28 #include <openssl/err.h>
29 #include <openssl/evp.h>
30
31 #include "avl_tree.h"
32 #include "conf.h"
33 #include "connection.h"
34 #include "device.h"
35 #include "event.h"
36 #include "graph.h"
37 #include "logger.h"
38 #include "net.h"
39 #include "netutl.h"
40 #include "process.h"
41 #include "protocol.h"
42 #include "route.h"
43 #include "subnet.h"
44 #include "utils.h"
45 #include "xalloc.h"
46
47 char *myport;
48 devops_t devops;
49
50 char *proxyhost;
51 char *proxyport;
52 char *proxyuser;
53 char *proxypass;
54 proxytype_t proxytype;
55
56 bool read_rsa_public_key(connection_t *c) {
57         FILE *fp;
58         char *pubname;
59         char *hcfname;
60         char *key;
61
62         if(!c->rsa_key) {
63                 c->rsa_key = RSA_new();
64 //              RSA_blinding_on(c->rsa_key, NULL);
65         }
66
67         /* First, check for simple PublicKey statement */
68
69         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
70                 if(BN_hex2bn(&c->rsa_key->n, key) != strlen(key)) {
71                         logger(LOG_ERR, "Invalid PublicKey for %s!", c->name);
72                         return false;
73                 }
74                 BN_hex2bn(&c->rsa_key->e, "FFFF");
75                 free(key);
76                 return true;
77         }
78
79         /* Else, check for PublicKeyFile statement and read it */
80
81         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &pubname)) {
82                 fp = fopen(pubname, "r");
83
84                 if(!fp) {
85                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s", pubname, strerror(errno));
86                         free(pubname);
87                         return false;
88                 }
89
90                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
91                 fclose(fp);
92
93                 if(c->rsa_key) {
94                         free(pubname);
95                         return true;            /* Woohoo. */
96                 }
97
98                 /* If it fails, try PEM_read_RSA_PUBKEY. */
99                 fp = fopen(pubname, "r");
100
101                 if(!fp) {
102                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s", pubname, strerror(errno));
103                         free(pubname);
104                         return false;
105                 }
106
107                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
108                 fclose(fp);
109
110                 if(c->rsa_key) {
111 //                              RSA_blinding_on(c->rsa_key, NULL);
112                         free(pubname);
113                         return true;
114                 }
115
116                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s", pubname, strerror(errno));
117                 free(pubname);
118                 return false;
119         }
120
121         /* Else, check if a harnessed public key is in the config file */
122
123         xasprintf(&hcfname, "%s/hosts/%s", confbase, c->name);
124         fp = fopen(hcfname, "r");
125
126         if(!fp) {
127                 logger(LOG_ERR, "Error reading RSA public key file `%s': %s", hcfname, strerror(errno));
128                 free(hcfname);
129                 return false;
130         }
131
132         c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
133         fclose(fp);
134
135         if(c->rsa_key) {
136                 free(hcfname);
137                 return true;
138         }
139
140         /* Try again with PEM_read_RSA_PUBKEY. */
141
142         fp = fopen(hcfname, "r");
143
144         if(!fp) {
145                 logger(LOG_ERR, "Error reading RSA public key file `%s': %s", hcfname, strerror(errno));
146                 free(hcfname);
147                 return false;
148         }
149
150         free(hcfname);
151         c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
152 //      RSA_blinding_on(c->rsa_key, NULL);
153         fclose(fp);
154
155         if(c->rsa_key)
156                 return true;
157
158         logger(LOG_ERR, "No public key for %s specified!", c->name);
159
160         return false;
161 }
162
163 static bool read_rsa_private_key(void) {
164         FILE *fp;
165         char *fname, *key, *pubkey;
166
167         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
168                 if(!get_config_string(lookup_config(config_tree, "PublicKey"), &pubkey)) {
169                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
170                         return false;
171                 }
172                 myself->connection->rsa_key = RSA_new();
173 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
174                 if(BN_hex2bn(&myself->connection->rsa_key->d, key) != strlen(key)) {
175                         logger(LOG_ERR, "Invalid PrivateKey for myself!");
176                         return false;
177                 }
178                 if(BN_hex2bn(&myself->connection->rsa_key->n, pubkey) != strlen(pubkey)) {
179                         logger(LOG_ERR, "Invalid PublicKey for myself!");
180                         return false;
181                 }
182                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
183                 free(key);
184                 free(pubkey);
185                 return true;
186         }
187
188         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
189                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
190
191         fp = fopen(fname, "r");
192
193         if(!fp) {
194                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
195                            fname, strerror(errno));
196                 free(fname);
197                 return false;
198         }
199
200 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
201         struct stat s;
202
203         if(fstat(fileno(fp), &s)) {
204                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
205                                 fname, strerror(errno));
206                 free(fname);
207                 return false;
208         }
209
210         if(s.st_mode & ~0100700)
211                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
212 #endif
213
214         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
215         fclose(fp);
216
217         if(!myself->connection->rsa_key) {
218                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s",
219                            fname, strerror(errno));
220                 free(fname);
221                 return false;
222         }
223
224         free(fname);
225         return true;
226 }
227
228 /*
229   Read Subnets from all host config files
230 */
231 void load_all_subnets(void) {
232         DIR *dir;
233         struct dirent *ent;
234         char *dname;
235         char *fname;
236         avl_tree_t *config_tree;
237         config_t *cfg;
238         subnet_t *s, *s2;
239         node_t *n;
240
241         xasprintf(&dname, "%s/hosts", confbase);
242         dir = opendir(dname);
243         if(!dir) {
244                 logger(LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
245                 free(dname);
246                 return;
247         }
248
249         while((ent = readdir(dir))) {
250                 if(!check_id(ent->d_name))
251                         continue;
252
253                 n = lookup_node(ent->d_name);
254                 #ifdef _DIRENT_HAVE_D_TYPE
255                 //if(ent->d_type != DT_REG)
256                 //      continue;
257                 #endif
258
259                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
260                 init_configuration(&config_tree);
261                 read_config_options(config_tree, ent->d_name);
262                 read_config_file(config_tree, fname);
263                 free(fname);
264
265                 if(!n) {
266                         n = new_node();
267                         n->name = xstrdup(ent->d_name);
268                         node_add(n);
269                 }
270
271                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
272                         if(!get_config_subnet(cfg, &s))
273                                 continue;
274
275                         if((s2 = lookup_subnet(n, s))) {
276                                 s2->expires = -1;
277                         } else {
278                                 subnet_add(n, s);
279                         }
280                 }
281
282                 exit_configuration(&config_tree);
283         }
284
285         closedir(dir);
286 }
287
288 char *get_name(void) {
289         char *name = NULL;
290
291         get_config_string(lookup_config(config_tree, "Name"), &name);
292
293         if(!name)
294                 return NULL;
295
296         if(*name == '$') {
297                 char *envname = getenv(name + 1);
298                 char hostname[32] = "";
299                 if(!envname) {
300                         if(strcmp(name + 1, "HOST")) {
301                                 fprintf(stderr, "Invalid Name: environment variable %s does not exist\n", name + 1);
302                                 return false;
303                         }
304                         if(gethostname(hostname, sizeof hostname) || !*hostname) {
305                                 fprintf(stderr, "Could not get hostname: %s\n", strerror(errno));
306                                 return false;
307                         }
308                         hostname[31] = 0;
309                         envname = hostname;
310                 }
311                 free(name);
312                 name = xstrdup(envname);
313                 for(char *c = name; *c; c++)
314                         if(!isalnum(*c))
315                                 *c = '_';
316         }
317
318         if(!check_id(name)) {
319                 logger(LOG_ERR, "Invalid name for myself!");
320                 free(name);
321                 return false;
322         }
323
324         return name;
325 }
326
327 /*
328   Configure node_t myself and set up the local sockets (listen only)
329 */
330 static bool setup_myself(void) {
331         config_t *cfg;
332         subnet_t *subnet;
333         char *name, *hostname, *mode, *afname, *cipher, *digest, *type;
334         char *fname = NULL;
335         char *address = NULL;
336         char *proxy = NULL;
337         char *space;
338         char *envp[5] = {NULL};
339         struct addrinfo *ai, *aip, hint = {0};
340         bool choice;
341         int i, err;
342         int replaywin_int;
343         bool port_specified = false;
344
345         myself = new_node();
346         myself->connection = new_connection();
347
348         myself->hostname = xstrdup("MYSELF");
349         myself->connection->hostname = xstrdup("MYSELF");
350
351         myself->connection->options = 0;
352         myself->connection->protocol_version = PROT_CURRENT;
353
354         if(!(name = get_name())) {
355                 logger(LOG_ERR, "Name for tinc daemon required!");
356                 return false;
357         }
358
359         /* Read tinc.conf and our own host config file */
360
361         myself->name = name;
362         myself->connection->name = xstrdup(name);
363         xasprintf(&fname, "%s/hosts/%s", confbase, name);
364         read_config_options(config_tree, name);
365         read_config_file(config_tree, fname);
366         free(fname);
367
368         if(!read_rsa_private_key())
369                 return false;
370
371         if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
372                 myport = xstrdup("655");
373         else
374                 port_specified = true;
375
376         /* Ensure myport is numeric */
377
378         if(!atoi(myport)) {
379                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
380                 sockaddr_t sa;
381                 if(!ai || !ai->ai_addr)
382                         return false;
383                 free(myport);
384                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
385                 sockaddr2str(&sa, NULL, &myport);
386         }
387
388         get_config_string(lookup_config(config_tree, "Proxy"), &proxy);
389         if(proxy) {
390                 if((space = strchr(proxy, ' ')))
391                         *space++ = 0;
392
393                 if(!strcasecmp(proxy, "none")) {
394                         proxytype = PROXY_NONE;
395                 } else if(!strcasecmp(proxy, "socks4")) {
396                         proxytype = PROXY_SOCKS4;
397                 } else if(!strcasecmp(proxy, "socks4a")) {
398                         proxytype = PROXY_SOCKS4A;
399                 } else if(!strcasecmp(proxy, "socks5")) {
400                         proxytype = PROXY_SOCKS5;
401                 } else if(!strcasecmp(proxy, "http")) {
402                         proxytype = PROXY_HTTP;
403                 } else if(!strcasecmp(proxy, "exec")) {
404                         proxytype = PROXY_EXEC;
405                 } else {
406                         logger(LOG_ERR, "Unknown proxy type %s!", proxy);
407                         return false;
408                 }
409
410                 switch(proxytype) {
411                         case PROXY_NONE:
412                         default:
413                                 break;
414
415                         case PROXY_EXEC:
416                                 if(!space || !*space) {
417                                         logger(LOG_ERR, "Argument expected for proxy type exec!");
418                                         return false;
419                                 }
420                                 proxyhost =  xstrdup(space);
421                                 break;
422
423                         case PROXY_SOCKS4:
424                         case PROXY_SOCKS4A:
425                         case PROXY_SOCKS5:
426                         case PROXY_HTTP:
427                                 proxyhost = space;
428                                 if(space && (space = strchr(space, ' ')))
429                                         *space++ = 0, proxyport = space;
430                                 if(space && (space = strchr(space, ' ')))
431                                         *space++ = 0, proxyuser = space;
432                                 if(space && (space = strchr(space, ' ')))
433                                         *space++ = 0, proxypass = space;
434                                 if(!proxyhost || !*proxyhost || !proxyport || !*proxyport) {
435                                         logger(LOG_ERR, "Host and port argument expected for proxy!");
436                                         return false;
437                                 }
438                                 proxyhost = xstrdup(proxyhost);
439                                 proxyport = xstrdup(proxyport);
440                                 if(proxyuser && *proxyuser)
441                                         proxyuser = xstrdup(proxyuser);
442                                 if(proxypass && *proxypass)
443                                         proxypass = xstrdup(proxypass);
444                                 break;
445                 }
446
447                 free(proxy);
448         }
449
450         /* Read in all the subnets specified in the host configuration file */
451
452         cfg = lookup_config(config_tree, "Subnet");
453
454         while(cfg) {
455                 if(!get_config_subnet(cfg, &subnet))
456                         return false;
457
458                 subnet_add(myself, subnet);
459
460                 cfg = lookup_config_next(config_tree, cfg);
461         }
462
463         /* Check some options */
464
465         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
466                 myself->options |= OPTION_INDIRECT;
467
468         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
469                 myself->options |= OPTION_TCPONLY;
470
471         if(myself->options & OPTION_TCPONLY)
472                 myself->options |= OPTION_INDIRECT;
473
474         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
475         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
476         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
477         get_config_bool(lookup_config(config_tree, "LocalDiscovery"), &localdiscovery);
478         strictsubnets |= tunnelserver;
479
480         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
481                 if(!strcasecmp(mode, "router"))
482                         routing_mode = RMODE_ROUTER;
483                 else if(!strcasecmp(mode, "switch"))
484                         routing_mode = RMODE_SWITCH;
485                 else if(!strcasecmp(mode, "hub"))
486                         routing_mode = RMODE_HUB;
487                 else {
488                         logger(LOG_ERR, "Invalid routing mode!");
489                         return false;
490                 }
491                 free(mode);
492         }
493
494         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
495                 if(!strcasecmp(mode, "off"))
496                         forwarding_mode = FMODE_OFF;
497                 else if(!strcasecmp(mode, "internal"))
498                         forwarding_mode = FMODE_INTERNAL;
499                 else if(!strcasecmp(mode, "kernel"))
500                         forwarding_mode = FMODE_KERNEL;
501                 else {
502                         logger(LOG_ERR, "Invalid forwarding mode!");
503                         return false;
504                 }
505                 free(mode);
506         }
507
508         choice = true;
509         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
510         if(choice)
511                 myself->options |= OPTION_PMTU_DISCOVERY;
512
513         choice = true;
514         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
515         if(choice)
516                 myself->options |= OPTION_CLAMP_MSS;
517
518         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
519         get_config_bool(lookup_config(config_tree, "DecrementTTL"), &decrement_ttl);
520         if(get_config_string(lookup_config(config_tree, "Broadcast"), &mode)) {
521                 if(!strcasecmp(mode, "no"))
522                         broadcast_mode = BMODE_NONE;
523                 else if(!strcasecmp(mode, "yes") || !strcasecmp(mode, "mst"))
524                         broadcast_mode = BMODE_MST;
525                 else if(!strcasecmp(mode, "direct"))
526                         broadcast_mode = BMODE_DIRECT;
527                 else {
528                         logger(LOG_ERR, "Invalid broadcast mode!");
529                         return false;
530                 }
531                 free(mode);
532         }
533
534 #if !defined(SOL_IP) || !defined(IP_TOS)
535         if(priorityinheritance)
536                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
537 #endif
538
539         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
540                 macexpire = 600;
541
542         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
543                 if(maxtimeout <= 0) {
544                         logger(LOG_ERR, "Bogus maximum timeout!");
545                         return false;
546                 }
547         } else
548                 maxtimeout = 900;
549
550         if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
551                 if(udp_rcvbuf <= 0) {
552                         logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
553                         return false;
554                 }
555         }
556
557         if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
558                 if(udp_sndbuf <= 0) {
559                         logger(LOG_ERR, "UDPSndBuf cannot be negative!");
560                         return false;
561                 }
562         }
563
564         if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
565                 if(replaywin_int < 0) {
566                         logger(LOG_ERR, "ReplayWindow cannot be negative!");
567                         return false;
568                 }
569                 replaywin = (unsigned)replaywin_int;
570         }
571
572         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
573                 if(!strcasecmp(afname, "IPv4"))
574                         addressfamily = AF_INET;
575                 else if(!strcasecmp(afname, "IPv6"))
576                         addressfamily = AF_INET6;
577                 else if(!strcasecmp(afname, "any"))
578                         addressfamily = AF_UNSPEC;
579                 else {
580                         logger(LOG_ERR, "Invalid address family!");
581                         return false;
582                 }
583                 free(afname);
584         }
585
586         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
587
588         /* Generate packet encryption key */
589
590         if(get_config_string
591            (lookup_config(config_tree, "Cipher"), &cipher)) {
592                 if(!strcasecmp(cipher, "none")) {
593                         myself->incipher = NULL;
594                 } else {
595                         myself->incipher = EVP_get_cipherbyname(cipher);
596
597                         if(!myself->incipher) {
598                                 logger(LOG_ERR, "Unrecognized cipher type!");
599                                 return false;
600                         }
601                 }
602         } else
603                 myself->incipher = EVP_bf_cbc();
604
605         if(myself->incipher)
606                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
607         else
608                 myself->inkeylength = 1;
609
610         myself->connection->outcipher = EVP_bf_ofb();
611
612         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
613                 keylifetime = 3600;
614
615         keyexpires = now + keylifetime;
616         
617         /* Check if we want to use message authentication codes... */
618
619         if(get_config_string(lookup_config(config_tree, "Digest"), &digest)) {
620                 if(!strcasecmp(digest, "none")) {
621                         myself->indigest = NULL;
622                 } else {
623                         myself->indigest = EVP_get_digestbyname(digest);
624
625                         if(!myself->indigest) {
626                                 logger(LOG_ERR, "Unrecognized digest type!");
627                                 return false;
628                         }
629                 }
630         } else
631                 myself->indigest = EVP_sha1();
632
633         myself->connection->outdigest = EVP_sha1();
634
635         if(get_config_int(lookup_config(config_tree, "MACLength"), &myself->inmaclength)) {
636                 if(myself->indigest) {
637                         if(myself->inmaclength > myself->indigest->md_size) {
638                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
639                                 return false;
640                         } else if(myself->inmaclength < 0) {
641                                 logger(LOG_ERR, "Bogus MAC length!");
642                                 return false;
643                         }
644                 }
645         } else
646                 myself->inmaclength = 4;
647
648         myself->connection->outmaclength = 0;
649
650         /* Compression */
651
652         if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
653                 if(myself->incompression < 0 || myself->incompression > 11) {
654                         logger(LOG_ERR, "Bogus compression level!");
655                         return false;
656                 }
657         } else
658                 myself->incompression = 0;
659
660         myself->connection->outcompression = 0;
661
662         /* Done */
663
664         myself->nexthop = myself;
665         myself->via = myself;
666         myself->status.reachable = true;
667         node_add(myself);
668
669         graph();
670
671         if(strictsubnets)
672                 load_all_subnets();
673
674         /* Open device */
675
676         devops = os_devops;
677
678         if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
679                 if(!strcasecmp(type, "dummy"))
680                         devops = dummy_devops;
681                 else if(!strcasecmp(type, "raw_socket"))
682                         devops = raw_socket_devops;
683                 else if(!strcasecmp(type, "multicast"))
684                         devops = multicast_devops;
685 #ifdef ENABLE_UML
686                 else if(!strcasecmp(type, "uml"))
687                         devops = uml_devops;
688 #endif
689 #ifdef ENABLE_VDE
690                 else if(!strcasecmp(type, "vde"))
691                         devops = vde_devops;
692 #endif
693         }
694
695         if(!devops.setup())
696                 return false;
697
698         /* Run tinc-up script to further initialize the tap interface */
699         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
700         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
701         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
702         xasprintf(&envp[3], "NAME=%s", myself->name);
703
704         execute_script("tinc-up", envp);
705
706         for(i = 0; i < 4; i++)
707                 free(envp[i]);
708
709         /* Run subnet-up scripts for our own subnets */
710
711         subnet_update(myself, NULL, true);
712
713         /* Open sockets */
714
715         if(!do_detach && getenv("LISTEN_FDS")) {
716                 sockaddr_t sa;
717                 socklen_t salen;
718
719                 listen_sockets = atoi(getenv("LISTEN_FDS"));
720 #ifdef HAVE_UNSETENV
721                 unsetenv("LISTEN_FDS");
722 #endif
723
724                 if(listen_sockets > MAXSOCKETS) {
725                         logger(LOG_ERR, "Too many listening sockets");
726                         return false;
727                 }
728
729                 for(i = 0; i < listen_sockets; i++) {
730                         salen = sizeof sa;
731                         if(getsockname(i + 3, &sa.sa, &salen) < 0) {
732                                 logger(LOG_ERR, "Could not get address of listen fd %d: %s", i + 3, sockstrerror(errno));
733                                 return false;
734                         }
735
736                         listen_socket[i].tcp = i + 3;
737
738 #ifdef FD_CLOEXEC
739                         fcntl(i + 3, F_SETFD, FD_CLOEXEC);
740 #endif
741
742                         listen_socket[i].udp = setup_vpn_in_socket(&sa);
743                         if(listen_socket[i].udp < 0)
744                                 return false;
745
746                         ifdebug(CONNECTIONS) {
747                                 hostname = sockaddr2hostname(&sa);
748                                 logger(LOG_NOTICE, "Listening on %s", hostname);
749                                 free(hostname);
750                         }
751
752                         memcpy(&listen_socket[i].sa, &sa, salen);
753                 }
754         } else {
755                 listen_sockets = 0;
756                 cfg = lookup_config(config_tree, "BindToAddress");
757
758                 do {
759                         get_config_string(cfg, &address);
760                         if(cfg)
761                                 cfg = lookup_config_next(config_tree, cfg);
762
763                         char *port = myport;
764
765                         if(address) {
766                                 char *space = strchr(address, ' ');
767                                 if(space) {
768                                         *space++ = 0;
769                                         port = space;
770                                 }
771
772                                 if(!strcmp(address, "*"))
773                                         *address = 0;
774                         }
775
776                         hint.ai_family = addressfamily;
777                         hint.ai_socktype = SOCK_STREAM;
778                         hint.ai_protocol = IPPROTO_TCP;
779                         hint.ai_flags = AI_PASSIVE;
780
781                         err = getaddrinfo(address && *address ? address : NULL, port, &hint, &ai);
782                         free(address);
783
784                         if(err || !ai) {
785                                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
786                                            gai_strerror(err));
787                                 return false;
788                         }
789
790                         for(aip = ai; aip; aip = aip->ai_next) {
791                                 if(listen_sockets >= MAXSOCKETS) {
792                                         logger(LOG_ERR, "Too many listening sockets");
793                                         return false;
794                                 }
795
796                                 listen_socket[listen_sockets].tcp =
797                                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
798
799                                 if(listen_socket[listen_sockets].tcp < 0)
800                                         continue;
801
802                                 listen_socket[listen_sockets].udp =
803                                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
804
805                                 if(listen_socket[listen_sockets].udp < 0)
806                                         continue;
807
808                                 ifdebug(CONNECTIONS) {
809                                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
810                                         logger(LOG_NOTICE, "Listening on %s", hostname);
811                                         free(hostname);
812                                 }
813
814                                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
815                                 listen_sockets++;
816                         }
817
818                         freeaddrinfo(ai);
819                 } while(cfg);
820         }
821
822         if(!listen_sockets) {
823                 logger(LOG_ERR, "Unable to create any listening socket!");
824                 return false;
825         }
826
827         /* If no Port option was specified, set myport to the port used by the first listening socket. */
828
829         if(!port_specified) {
830                 sockaddr_t sa;
831                 socklen_t salen = sizeof sa;
832                 if(!getsockname(listen_socket[0].udp, &sa.sa, &salen)) {
833                         free(myport);
834                         sockaddr2str(&sa, NULL, &myport);
835                         if(!myport)
836                                 myport = xstrdup("655");
837                 }
838         }
839
840         /* Done. */
841
842         logger(LOG_NOTICE, "Ready");
843         return true;
844 }
845
846 /*
847   initialize network
848 */
849 bool setup_network(void) {
850         now = time(NULL);
851
852         init_events();
853         init_connections();
854         init_subnets();
855         init_nodes();
856         init_edges();
857         init_requests();
858
859         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
860                 if(pinginterval < 1) {
861                         pinginterval = 86400;
862                 }
863         } else
864                 pinginterval = 60;
865
866         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
867                 pingtimeout = 5;
868         if(pingtimeout < 1 || pingtimeout > pinginterval)
869                 pingtimeout = pinginterval;
870
871         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
872                 maxoutbufsize = 10 * MTU;
873
874         if(!setup_myself())
875                 return false;
876
877         return true;
878 }
879
880 /*
881   close all open network connections
882 */
883 void close_network_connections(void) {
884         avl_node_t *node, *next;
885         connection_t *c;
886         char *envp[5] = {NULL};
887         int i;
888
889         for(node = connection_tree->head; node; node = next) {
890                 next = node->next;
891                 c = node->data;
892                 c->outgoing = NULL;
893                 terminate_connection(c, false);
894         }
895
896         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
897                 outgoing_t *outgoing = node->data;
898
899                 if(outgoing->event)
900                         event_del(outgoing->event);
901         }
902
903         list_delete_list(outgoing_list);
904
905         if(myself && myself->connection) {
906                 subnet_update(myself, NULL, false);
907                 terminate_connection(myself->connection, false);
908                 free_connection(myself->connection);
909         }
910
911         for(i = 0; i < listen_sockets; i++) {
912                 close(listen_socket[i].tcp);
913                 close(listen_socket[i].udp);
914         }
915
916         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
917         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
918         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
919         xasprintf(&envp[3], "NAME=%s", myself->name);
920
921         exit_requests();
922         exit_edges();
923         exit_subnets();
924         exit_nodes();
925         exit_connections();
926         exit_events();
927
928         execute_script("tinc-down", envp);
929
930         if(myport) free(myport);
931
932         for(i = 0; i < 4; i++)
933                 free(envp[i]);
934
935         devops.close();
936
937         return;
938 }