3c4bf48c71607795b8c5f4bedbc44436ef2e1991
[tinc] / src / net_setup.c
1 /*
2     net_setup.c -- Setup.
3     Copyright (C) 1998-2005 Ivo Timmermans,
4                   2000-2009 Guus Sliepen <guus@tinc-vpn.org>
5
6     This program is free software; you can redistribute it and/or modify
7     it under the terms of the GNU General Public License as published by
8     the Free Software Foundation; either version 2 of the License, or
9     (at your option) any later version.
10
11     This program is distributed in the hope that it will be useful,
12     but WITHOUT ANY WARRANTY; without even the implied warranty of
13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14     GNU General Public License for more details.
15
16     You should have received a copy of the GNU General Public License
17     along with this program; if not, write to the Free Software
18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19
20     $Id$
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
49 bool read_rsa_public_key(connection_t *c)
50 {
51         FILE *fp;
52         char *fname;
53         char *key;
54
55         cp();
56
57         if(!c->rsa_key) {
58                 c->rsa_key = RSA_new();
59 //              RSA_blinding_on(c->rsa_key, NULL);
60         }
61
62         /* First, check for simple PublicKey statement */
63
64         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
65                 BN_hex2bn(&c->rsa_key->n, key);
66                 BN_hex2bn(&c->rsa_key->e, "FFFF");
67                 free(key);
68                 return true;
69         }
70
71         /* Else, check for PublicKeyFile statement and read it */
72
73         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
74                 fp = fopen(fname, "r");
75
76                 if(!fp) {
77                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
78                                    fname, strerror(errno));
79                         free(fname);
80                         return false;
81                 }
82
83                 free(fname);
84                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
85                 fclose(fp);
86
87                 if(c->rsa_key)
88                         return true;            /* Woohoo. */
89
90                 /* If it fails, try PEM_read_RSA_PUBKEY. */
91                 fp = fopen(fname, "r");
92
93                 if(!fp) {
94                         logger(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
95                                    fname, strerror(errno));
96                         free(fname);
97                         return false;
98                 }
99
100                 free(fname);
101                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
102                 fclose(fp);
103
104                 if(c->rsa_key) {
105 //                              RSA_blinding_on(c->rsa_key, NULL);
106                         return true;
107                 }
108
109                 logger(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
110                            fname, strerror(errno));
111                 return false;
112         }
113
114         /* Else, check if a harnessed public key is in the config file */
115
116         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
117         fp = fopen(fname, "r");
118
119         if(fp) {
120                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
121                 fclose(fp);
122         }
123
124         free(fname);
125
126         if(c->rsa_key)
127                 return true;
128
129         /* Try again with PEM_read_RSA_PUBKEY. */
130
131         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
132         fp = fopen(fname, "r");
133
134         if(fp) {
135                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
136 //              RSA_blinding_on(c->rsa_key, NULL);
137                 fclose(fp);
138         }
139
140         free(fname);
141
142         if(c->rsa_key)
143                 return true;
144
145         logger(LOG_ERR, _("No public key for %s specified!"), c->name);
146
147         return false;
148 }
149
150 bool read_rsa_private_key(void)
151 {
152         FILE *fp;
153         char *fname, *key, *pubkey;
154         struct stat s;
155
156         cp();
157
158         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
159                 if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &pubkey)) {
160                         logger(LOG_ERR, _("PrivateKey used but no PublicKey found!"));
161                         return false;
162                 }
163                 myself->connection->rsa_key = RSA_new();
164 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
165                 BN_hex2bn(&myself->connection->rsa_key->d, key);
166                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
167                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
168                 free(key);
169                 free(pubkey);
170                 return true;
171         }
172
173         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
174                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
175
176         fp = fopen(fname, "r");
177
178         if(!fp) {
179                 logger(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
180                            fname, strerror(errno));
181                 free(fname);
182                 return false;
183         }
184
185 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
186         if(fstat(fileno(fp), &s)) {
187                 logger(LOG_ERR, _("Could not stat RSA private key file `%s': %s'"),
188                                 fname, strerror(errno));
189                 free(fname);
190                 return false;
191         }
192
193         if(s.st_mode & ~0100700)
194                 logger(LOG_WARNING, _("Warning: insecure file permissions for RSA private key file `%s'!"), fname);
195 #endif
196
197         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
198         fclose(fp);
199
200         if(!myself->connection->rsa_key) {
201                 logger(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
202                            fname, strerror(errno));
203                 free(fname);
204                 return false;
205         }
206
207         free(fname);
208         return true;
209 }
210
211 /*
212   Configure node_t myself and set up the local sockets (listen only)
213 */
214 bool setup_myself(void)
215 {
216         config_t *cfg;
217         subnet_t *subnet;
218         char *name, *hostname, *mode, *afname, *cipher, *digest;
219         char *address = NULL;
220         char *envp[5];
221         struct addrinfo *ai, *aip, hint = {0};
222         bool choice;
223         int i, err;
224
225         cp();
226
227         myself = new_node();
228         myself->connection = new_connection();
229         init_configuration(&myself->connection->config_tree);
230
231         xasprintf(&myself->hostname, _("MYSELF"));
232         xasprintf(&myself->connection->hostname, _("MYSELF"));
233
234         myself->connection->options = 0;
235         myself->connection->protocol_version = PROT_CURRENT;
236
237         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
238                 logger(LOG_ERR, _("Name for tinc daemon required!"));
239                 return false;
240         }
241
242         if(!check_id(name)) {
243                 logger(LOG_ERR, _("Invalid name for myself!"));
244                 free(name);
245                 return false;
246         }
247
248         myself->name = name;
249         myself->connection->name = xstrdup(name);
250
251         if(!read_connection_config(myself->connection)) {
252                 logger(LOG_ERR, _("Cannot open host configuration file for myself!"));
253                 return false;
254         }
255
256         if(!read_rsa_private_key())
257                 return false;
258
259         if(!get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
260                 xasprintf(&myport, "655");
261
262         /* Read in all the subnets specified in the host configuration file */
263
264         cfg = lookup_config(myself->connection->config_tree, "Subnet");
265
266         while(cfg) {
267                 if(!get_config_subnet(cfg, &subnet))
268                         return false;
269
270                 subnet_add(myself, subnet);
271
272                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
273         }
274
275         /* Check some options */
276
277         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
278                 myself->options |= OPTION_INDIRECT;
279
280         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
281                 myself->options |= OPTION_TCPONLY;
282
283         if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
284                 myself->options |= OPTION_INDIRECT;
285
286         if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
287                 myself->options |= OPTION_TCPONLY;
288
289         if(myself->options & OPTION_TCPONLY)
290                 myself->options |= OPTION_INDIRECT;
291
292         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
293
294         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
295                 if(!strcasecmp(mode, "router"))
296                         routing_mode = RMODE_ROUTER;
297                 else if(!strcasecmp(mode, "switch"))
298                         routing_mode = RMODE_SWITCH;
299                 else if(!strcasecmp(mode, "hub"))
300                         routing_mode = RMODE_HUB;
301                 else {
302                         logger(LOG_ERR, _("Invalid routing mode!"));
303                         return false;
304                 }
305                 free(mode);
306         } else
307                 routing_mode = RMODE_ROUTER;
308
309         // Enable PMTUDiscovery by default if we are in router mode.
310
311         choice = routing_mode == RMODE_ROUTER;
312         get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
313         if(choice)      
314                 myself->options |= OPTION_PMTU_DISCOVERY;
315
316         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
317
318 #if !defined(SOL_IP) || !defined(IP_TOS)
319         if(priorityinheritance)
320                 logger(LOG_WARNING, _("%s not supported on this platform"), "PriorityInheritance");
321 #endif
322
323         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
324                 macexpire = 600;
325
326         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
327                 if(maxtimeout <= 0) {
328                         logger(LOG_ERR, _("Bogus maximum timeout!"));
329                         return false;
330                 }
331         } else
332                 maxtimeout = 900;
333
334         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
335                 if(!strcasecmp(afname, "IPv4"))
336                         addressfamily = AF_INET;
337                 else if(!strcasecmp(afname, "IPv6"))
338                         addressfamily = AF_INET6;
339                 else if(!strcasecmp(afname, "any"))
340                         addressfamily = AF_UNSPEC;
341                 else {
342                         logger(LOG_ERR, _("Invalid address family!"));
343                         return false;
344                 }
345                 free(afname);
346         }
347
348         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
349
350         /* Generate packet encryption key */
351
352         if(get_config_string
353            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
354                 if(!strcasecmp(cipher, "none")) {
355                         myself->incipher = NULL;
356                 } else {
357                         myself->incipher = EVP_get_cipherbyname(cipher);
358
359                         if(!myself->incipher) {
360                                 logger(LOG_ERR, _("Unrecognized cipher type!"));
361                                 return false;
362                         }
363                 }
364         } else
365                 myself->incipher = EVP_aes_256_cbc();
366
367         if(myself->incipher)
368                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
369         else
370                 myself->inkeylength = 1;
371
372         myself->connection->outcipher = EVP_aes_256_ofb();
373
374         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
375                 keylifetime = 3600;
376
377         keyexpires = now + keylifetime;
378         
379         /* Check if we want to use message authentication codes... */
380
381         if(get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
382                 if(!strcasecmp(digest, "none")) {
383                         myself->indigest = NULL;
384                 } else {
385                         myself->indigest = EVP_get_digestbyname(digest);
386
387                         if(!myself->indigest) {
388                                 logger(LOG_ERR, _("Unrecognized digest type!"));
389                                 return false;
390                         }
391                 }
392         } else
393                 myself->indigest = EVP_sha256();
394
395         myself->connection->outdigest = EVP_sha256();
396
397         if(get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &myself->inmaclength)) {
398                 if(myself->indigest) {
399                         if(myself->inmaclength > myself->indigest->md_size) {
400                                 logger(LOG_ERR, _("MAC length exceeds size of digest!"));
401                                 return false;
402                         } else if(myself->inmaclength < 0) {
403                                 logger(LOG_ERR, _("Bogus MAC length!"));
404                                 return false;
405                         }
406                 }
407         } else
408                 myself->inmaclength = 4;
409
410         myself->connection->outmaclength = 0;
411
412         /* Compression */
413
414         if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
415                 if(myself->incompression < 0 || myself->incompression > 11) {
416                         logger(LOG_ERR, _("Bogus compression level!"));
417                         return false;
418                 }
419         } else
420                 myself->incompression = 0;
421
422         myself->connection->outcompression = 0;
423
424         /* Done */
425
426         myself->nexthop = myself;
427         myself->via = myself;
428         myself->status.reachable = true;
429         node_add(myself);
430
431         graph();
432
433         /* Open device */
434
435         if(!setup_device())
436                 return false;
437
438         /* Run tinc-up script to further initialize the tap interface */
439         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
440         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
441         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
442         xasprintf(&envp[3], "NAME=%s", myself->name);
443         envp[4] = NULL;
444
445         execute_script("tinc-up", envp);
446
447         for(i = 0; i < 5; i++)
448                 free(envp[i]);
449
450         /* Run subnet-up scripts for our own subnets */
451
452         subnet_update(myself, NULL, true);
453
454         /* Open sockets */
455
456         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
457
458         hint.ai_family = addressfamily;
459         hint.ai_socktype = SOCK_STREAM;
460         hint.ai_protocol = IPPROTO_TCP;
461         hint.ai_flags = AI_PASSIVE;
462
463         err = getaddrinfo(address, myport, &hint, &ai);
464
465         if(err || !ai) {
466                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
467                            gai_strerror(err));
468                 return false;
469         }
470
471         listen_sockets = 0;
472
473         for(aip = ai; aip; aip = aip->ai_next) {
474                 listen_socket[listen_sockets].tcp =
475                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
476
477                 if(listen_socket[listen_sockets].tcp < 0)
478                         continue;
479
480                 listen_socket[listen_sockets].udp =
481                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
482
483                 if(listen_socket[listen_sockets].udp < 0)
484                         continue;
485
486                 ifdebug(CONNECTIONS) {
487                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
488                         logger(LOG_NOTICE, _("Listening on %s"), hostname);
489                         free(hostname);
490                 }
491
492                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
493                 listen_sockets++;
494         }
495
496         freeaddrinfo(ai);
497
498         if(listen_sockets)
499                 logger(LOG_NOTICE, _("Ready"));
500         else {
501                 logger(LOG_ERR, _("Unable to create any listening socket!"));
502                 return false;
503         }
504
505         return true;
506 }
507
508 /*
509   initialize network
510 */
511 bool setup_network(void)
512 {
513         cp();
514
515         now = time(NULL);
516
517         init_events();
518         init_connections();
519         init_subnets();
520         init_nodes();
521         init_edges();
522         init_requests();
523
524         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
525                 if(pinginterval < 1) {
526                         pinginterval = 86400;
527                 }
528         } else
529                 pinginterval = 60;
530
531         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
532                 pingtimeout = 5;
533         if(pingtimeout < 1 || pingtimeout > pinginterval)
534                 pingtimeout = pinginterval;
535
536         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
537                 maxoutbufsize = 10 * MTU;
538
539         if(!setup_myself())
540                 return false;
541
542         return true;
543 }
544
545 /*
546   close all open network connections
547 */
548 void close_network_connections(void)
549 {
550         avl_node_t *node, *next;
551         connection_t *c;
552         char *envp[5];
553         int i;
554
555         cp();
556
557         for(node = connection_tree->head; node; node = next) {
558                 next = node->next;
559                 c = node->data;
560                 c->outgoing = false;
561                 terminate_connection(c, false);
562         }
563
564         list_delete_list(outgoing_list);
565
566         if(myself && myself->connection) {
567                 subnet_update(myself, NULL, false);
568                 terminate_connection(myself->connection, false);
569                 free_connection(myself->connection);
570         }
571
572         for(i = 0; i < listen_sockets; i++) {
573                 close(listen_socket[i].tcp);
574                 close(listen_socket[i].udp);
575         }
576
577         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
578         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
579         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
580         xasprintf(&envp[3], "NAME=%s", myself->name);
581         envp[4] = NULL;
582
583         exit_requests();
584         exit_edges();
585         exit_subnets();
586         exit_nodes();
587         exit_connections();
588         exit_events();
589
590         execute_script("tinc-down", envp);
591
592         if(myport) free(myport);
593
594         for(i = 0; i < 4; i++)
595                 free(envp[i]);
596
597         close_device();
598
599         return;
600 }