src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2002 Ivo Timmermans <ivo@o2w.nl>,
   4                   2000-2002 Guus Sliepen <guus@sliepen.eu.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: net_setup.c,v 1.1.2.31 2003/05/06 21:13:17 guus Exp $
  21 */
  22
  23 #include "config.h"
  24
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <netdb.h>
  28 #include <netinet/in.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <signal.h>
  33 #include <sys/time.h>
  34 #include <sys/types.h>
  35 #include <syslog.h>
  36 #include <unistd.h>
  37 #include <sys/ioctl.h>
  38 /* SunOS really wants sys/socket.h BEFORE net/if.h,
  39    and FreeBSD wants these lines below the rest. */
  40 #include <arpa/inet.h>
  41 #include <sys/socket.h>
  42 #include <net/if.h>
  43 #ifdef HAVE_NETINET_IN_SYSTM_H
  44 #include <netinet/in_systm.h>
  45 #endif
  46 #ifdef HAVE_NETINET_IP_H
  47 #include <netinet/ip.h>
  48 #endif
  49 #ifdef HAVE_NETINET_TCP_H
  50 #include <netinet/tcp.h>
  51 #endif
  52
  53 #include <openssl/pem.h>
  54 #include <openssl/rsa.h>
  55 #include <openssl/rand.h>
  56
  57 #include <utils.h>
  58 #include <xalloc.h>
  59 #include <avl_tree.h>
  60 #include <list.h>
  61
  62 #include "conf.h"
  63 #include "connection.h"
  64 #include "meta.h"
  65 #include "net.h"
  66 #include "netutl.h"
  67 #include "process.h"
  68 #include "protocol.h"
  69 #include "subnet.h"
  70 #include "graph.h"
  71 #include "process.h"
  72 #include "route.h"
  73 #include "device.h"
  74 #include "event.h"
  75
  76 #include "system.h"
  77
  78 char *myport;
  79
  80 int read_rsa_public_key(connection_t *c)
  81 {
  82         FILE *fp;
  83         char *fname;
  84         char *key;
  85
  86         cp();
  87
  88         if(!c->rsa_key) {
  89                 c->rsa_key = RSA_new();
  90 //              RSA_blinding_on(c->rsa_key, NULL);
  91         }
  92
  93         /* First, check for simple PublicKey statement */
  94
  95         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  96                 BN_hex2bn(&c->rsa_key->n, key);
  97                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  98                 free(key);
  99                 return 0;
 100         }
 101
 102         /* Else, check for PublicKeyFile statement and read it */
 103
 104         if(get_config_string
 105            (lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
 106                 if(is_safe_path(fname)) {
 107                         fp = fopen(fname, "r");
 108
 109                         if(!fp) {
 110                                 syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 111                                            fname, strerror(errno));
 112                                 free(fname);
 113                                 return -1;
 114                         }
 115
 116                         free(fname);
 117                         c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 118                         fclose(fp);
 119
 120                         if(c->rsa_key)
 121                                 return 0;               /* Woohoo. */
 122
 123                         /* If it fails, try PEM_read_RSA_PUBKEY. */
 124                         fp = fopen(fname, "r");
 125
 126                         if(!fp) {
 127                                 syslog(LOG_ERR, _("Error reading RSA public key file `%s': %s"),
 128                                            fname, strerror(errno));
 129                                 free(fname);
 130                                 return -1;
 131                         }
 132
 133                         free(fname);
 134                         c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 135                         fclose(fp);
 136
 137                         if(c->rsa_key) {
 138 //                              RSA_blinding_on(c->rsa_key, NULL);
 139                                 return 0;
 140                         }
 141
 142                         syslog(LOG_ERR, _("Reading RSA public key file `%s' failed: %s"),
 143                                    fname, strerror(errno));
 144                         return -1;
 145                 } else {
 146                         free(fname);
 147                         return -1;
 148                 }
 149         }
 150
 151         /* Else, check if a harnessed public key is in the config file */
 152
 153         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 154         fp = fopen(fname, "r");
 155
 156         if(fp) {
 157                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 158                 fclose(fp);
 159         }
 160
 161         free(fname);
 162
 163         if(c->rsa_key)
 164                 return 0;
 165
 166         /* Try again with PEM_read_RSA_PUBKEY. */
 167
 168         asprintf(&fname, "%s/hosts/%s", confbase, c->name);
 169         fp = fopen(fname, "r");
 170
 171         if(fp) {
 172                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 173 //              RSA_blinding_on(c->rsa_key, NULL);
 174                 fclose(fp);
 175         }
 176
 177         free(fname);
 178
 179         if(c->rsa_key)
 180                 return 0;
 181
 182         syslog(LOG_ERR, _("No public key for %s specified!"), c->name);
 183
 184         return -1;
 185 }
 186
 187 int read_rsa_private_key(void)
 188 {
 189         FILE *fp;
 190         char *fname, *key;
 191
 192         cp();
 193
 194         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 195                 myself->connection->rsa_key = RSA_new();
 196 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 197                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 198                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 199                 free(key);
 200                 return 0;
 201         }
 202
 203         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 204                 asprintf(&fname, "%s/rsa_key.priv", confbase);
 205
 206         if(is_safe_path(fname)) {
 207                 fp = fopen(fname, "r");
 208
 209                 if(!fp) {
 210                         syslog(LOG_ERR, _("Error reading RSA private key file `%s': %s"),
 211                                    fname, strerror(errno));
 212                         free(fname);
 213                         return -1;
 214                 }
 215
 216                 free(fname);
 217                 myself->connection->rsa_key =
 218                         PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 219                 fclose(fp);
 220
 221                 if(!myself->connection->rsa_key) {
 222                         syslog(LOG_ERR, _("Reading RSA private key file `%s' failed: %s"),
 223                                    fname, strerror(errno));
 224                         return -1;
 225                 }
 226
 227                 return 0;
 228         }
 229
 230         free(fname);
 231         return -1;
 232 }
 233
 234 /*
 235   Configure node_t myself and set up the local sockets (listen only)
 236 */
 237 int setup_myself(void)
 238 {
 239         config_t *cfg;
 240         subnet_t *subnet;
 241         char *name, *hostname, *mode, *afname, *cipher, *digest;
 242         char *address = NULL;
 243         struct addrinfo hint, *ai, *aip;
 244         int choice, err;
 245
 246         cp();
 247
 248         myself = new_node();
 249         myself->connection = new_connection();
 250         init_configuration(&myself->connection->config_tree);
 251
 252         asprintf(&myself->hostname, _("MYSELF"));
 253         asprintf(&myself->connection->hostname, _("MYSELF"));
 254
 255         myself->connection->options = 0;
 256         myself->connection->protocol_version = PROT_CURRENT;
 257
 258         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 259                 syslog(LOG_ERR, _("Name for tinc daemon required!"));
 260                 return -1;
 261         }
 262
 263         if(check_id(name)) {
 264                 syslog(LOG_ERR, _("Invalid name for myself!"));
 265                 free(name);
 266                 return -1;
 267         }
 268
 269         myself->name = name;
 270         myself->connection->name = xstrdup(name);
 271
 272         if(read_rsa_private_key())
 273                 return -1;
 274
 275         if(read_connection_config(myself->connection)) {
 276                 syslog(LOG_ERR, _("Cannot open host configuration file for myself!"));
 277                 return -1;
 278         }
 279
 280         if(read_rsa_public_key(myself->connection))
 281                 return -1;
 282
 283         if(!get_config_string
 284            (lookup_config(myself->connection->config_tree, "Port"), &myport))
 285                 asprintf(&myport, "655");
 286
 287         /* Read in all the subnets specified in the host configuration file */
 288
 289         cfg = lookup_config(myself->connection->config_tree, "Subnet");
 290
 291         while(cfg) {
 292                 if(!get_config_subnet(cfg, &subnet))
 293                         return -1;
 294
 295                 subnet_add(myself, subnet);
 296
 297                 cfg = lookup_config_next(myself->connection->config_tree, cfg);
 298         }
 299
 300         /* Check some options */
 301
 302         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
 303                 if(choice)
 304                         myself->options |= OPTION_INDIRECT;
 305
 306         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
 307                 if(choice)
 308                         myself->options |= OPTION_TCPONLY;
 309
 310         if(get_config_bool
 311            (lookup_config(myself->connection->config_tree, "IndirectData"),
 312                 &choice))
 313                 if(choice)
 314                         myself->options |= OPTION_INDIRECT;
 315
 316         if(get_config_bool
 317            (lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
 318                 if(choice)
 319                         myself->options |= OPTION_TCPONLY;
 320
 321         if(myself->options & OPTION_TCPONLY)
 322                 myself->options |= OPTION_INDIRECT;
 323
 324         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 325                 if(!strcasecmp(mode, "router"))
 326                         routing_mode = RMODE_ROUTER;
 327                 else if(!strcasecmp(mode, "switch"))
 328                         routing_mode = RMODE_SWITCH;
 329                 else if(!strcasecmp(mode, "hub"))
 330                         routing_mode = RMODE_HUB;
 331                 else {
 332                         syslog(LOG_ERR, _("Invalid routing mode!"));
 333                         return -1;
 334                 }
 335                 free(mode);
 336         } else
 337                 routing_mode = RMODE_ROUTER;
 338
 339         get_config_bool(lookup_config(config_tree, "PriorityInheritance"),
 340                                         &priorityinheritance);
 341 #if !defined(SOL_IP) || !defined(IP_TOS)
 342         if(priorityinheritance)
 343                 syslog(LOG_WARNING, _("PriorityInheritance not supported on this platform"));
 344 #endif
 345
 346         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 347                 macexpire = 600;
 348
 349         if(get_config_int
 350            (lookup_config(myself->connection->config_tree, "MaxTimeout"),
 351                 &maxtimeout)) {
 352                 if(maxtimeout <= 0) {
 353                         syslog(LOG_ERR, _("Bogus maximum timeout!"));
 354                         return -1;
 355                 }
 356         } else
 357                 maxtimeout = 900;
 358
 359         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 360                 if(!strcasecmp(afname, "IPv4"))
 361                         addressfamily = AF_INET;
 362                 else if(!strcasecmp(afname, "IPv6"))
 363                         addressfamily = AF_INET6;
 364                 else if(!strcasecmp(afname, "any"))
 365                         addressfamily = AF_UNSPEC;
 366                 else {
 367                         syslog(LOG_ERR, _("Invalid address family!"));
 368                         return -1;
 369                 }
 370                 free(afname);
 371         } else
 372                 addressfamily = AF_INET;
 373
 374         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 375
 376         /* Generate packet encryption key */
 377
 378         if(get_config_string
 379            (lookup_config(myself->connection->config_tree, "Cipher"), &cipher)) {
 380                 if(!strcasecmp(cipher, "none")) {
 381                         myself->cipher = NULL;
 382                 } else {
 383                         myself->cipher = EVP_get_cipherbyname(cipher);
 384
 385                         if(!myself->cipher) {
 386                                 syslog(LOG_ERR, _("Unrecognized cipher type!"));
 387                                 return -1;
 388                         }
 389                 }
 390         } else
 391                 myself->cipher = EVP_bf_cbc();
 392
 393         if(myself->cipher)
 394                 myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
 395         else
 396                 myself->keylength = 1;
 397
 398         myself->connection->outcipher = EVP_bf_ofb();
 399
 400         myself->key = (char *) xmalloc(myself->keylength);
 401         RAND_pseudo_bytes(myself->key, myself->keylength);
 402
 403         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 404                 keylifetime = 3600;
 405
 406         keyexpires = now + keylifetime;
 407
 408         EVP_CIPHER_CTX_init(&packet_ctx);
 409         EVP_DecryptInit_ex(&packet_ctx, myself->cipher, NULL, myself->key, myself->key + myself->cipher->key_len);
 410
 411         /* Check if we want to use message authentication codes... */
 412
 413         if(get_config_string
 414            (lookup_config(myself->connection->config_tree, "Digest"), &digest)) {
 415                 if(!strcasecmp(digest, "none")) {
 416                         myself->digest = NULL;
 417                 } else {
 418                         myself->digest = EVP_get_digestbyname(digest);
 419
 420                         if(!myself->digest) {
 421                                 syslog(LOG_ERR, _("Unrecognized digest type!"));
 422                                 return -1;
 423                         }
 424                 }
 425         } else
 426                 myself->digest = EVP_sha1();
 427
 428         myself->connection->outdigest = EVP_sha1();
 429
 430         if(get_config_int
 431            (lookup_config(myself->connection->config_tree, "MACLength"),
 432                 &myself->maclength)) {
 433                 if(myself->digest) {
 434                         if(myself->maclength > myself->digest->md_size) {
 435                                 syslog(LOG_ERR, _("MAC length exceeds size of digest!"));
 436                                 return -1;
 437                         } else if(myself->maclength < 0) {
 438                                 syslog(LOG_ERR, _("Bogus MAC length!"));
 439                                 return -1;
 440                         }
 441                 }
 442         } else
 443                 myself->maclength = 4;
 444
 445         myself->connection->outmaclength = 0;
 446
 447         /* Compression */
 448
 449         if(get_config_int
 450            (lookup_config(myself->connection->config_tree, "Compression"),
 451                 &myself->compression)) {
 452                 if(myself->compression < 0 || myself->compression > 11) {
 453                         syslog(LOG_ERR, _("Bogus compression level!"));
 454                         return -1;
 455                 }
 456         } else
 457                 myself->compression = 0;
 458
 459         myself->connection->outcompression = 0;
 460
 461         /* Done */
 462
 463         myself->nexthop = myself;
 464         myself->via = myself;
 465         myself->status.active = 1;
 466         myself->status.reachable = 1;
 467         node_add(myself);
 468
 469         graph();
 470
 471         /* Open sockets */
 472
 473         memset(&hint, 0, sizeof(hint));
 474
 475         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 476
 477         hint.ai_family = addressfamily;
 478         hint.ai_socktype = SOCK_STREAM;
 479         hint.ai_protocol = IPPROTO_TCP;
 480         hint.ai_flags = AI_PASSIVE;
 481
 482         err = getaddrinfo(address, myport, &hint, &ai);
 483
 484         if(err || !ai) {
 485                 syslog(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo",
 486                            gai_strerror(err));
 487                 return -1;
 488         }
 489
 490         listen_sockets = 0;
 491
 492         for(aip = ai; aip; aip = aip->ai_next) {
 493                 listen_socket[listen_sockets].tcp =
 494                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 495
 496                 if(listen_socket[listen_sockets].tcp < 0)
 497                         continue;
 498
 499                 listen_socket[listen_sockets].udp =
 500                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 501
 502                 if(listen_socket[listen_sockets].udp < 0)
 503                         continue;
 504
 505                 if(debug_lvl >= DEBUG_CONNECTIONS) {
 506                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 507                         syslog(LOG_NOTICE, _("Listening on %s"), hostname);
 508                         free(hostname);
 509                 }
 510
 511                 listen_socket[listen_sockets].sa.sa = *aip->ai_addr;
 512                 listen_sockets++;
 513         }
 514
 515         freeaddrinfo(ai);
 516
 517         if(listen_sockets)
 518                 syslog(LOG_NOTICE, _("Ready"));
 519         else {
 520                 syslog(LOG_ERR, _("Unable to create any listening socket!"));
 521                 return -1;
 522         }
 523
 524         return 0;
 525 }
 526
 527 /*
 528   setup all initial network connections
 529 */
 530 int setup_network_connections(void)
 531 {
 532         char *envp[5];
 533         int i;
 534
 535         cp();
 536
 537         now = time(NULL);
 538
 539         init_connections();
 540         init_subnets();
 541         init_nodes();
 542         init_edges();
 543         init_events();
 544         init_requests();
 545
 546         if(get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout)) {
 547                 if(pingtimeout < 1) {
 548                         pingtimeout = 86400;
 549                 }
 550         } else
 551                 pingtimeout = 60;
 552
 553         if(setup_device() < 0)
 554                 return -1;
 555
 556         if(setup_myself() < 0)
 557                 return -1;
 558
 559         /* Run tinc-up script to further initialize the tap interface */
 560         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 561         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 562         asprintf(&envp[2], "INTERFACE=%s", interface ? : "");
 563         asprintf(&envp[3], "NAME=%s", myself->name);
 564         envp[4] = NULL;
 565
 566         execute_script("tinc-up", envp);
 567
 568         for(i = 0; i < 5; i++)
 569                 free(envp[i]);
 570
 571         try_outgoing_connections();
 572
 573         return 0;
 574 }
 575
 576 /*
 577   close all open network connections
 578 */
 579 void close_network_connections(void)
 580 {
 581         avl_node_t *node, *next;
 582         connection_t *c;
 583         char *envp[5];
 584         int i;
 585
 586         cp();
 587
 588         for(node = connection_tree->head; node; node = next) {
 589                 next = node->next;
 590                 c = (connection_t *) node->data;
 591
 592                 if(c->outgoing)
 593                         free(c->outgoing->name), free(c->outgoing), c->outgoing = NULL;
 594                 terminate_connection(c, 0);
 595         }
 596
 597         if(myself && myself->connection)
 598                 terminate_connection(myself->connection, 0);
 599
 600         for(i = 0; i < listen_sockets; i++) {
 601                 close(listen_socket[i].tcp);
 602                 close(listen_socket[i].udp);
 603         }
 604
 605         exit_requests();
 606         exit_events();
 607         exit_edges();
 608         exit_subnets();
 609         exit_nodes();
 610         exit_connections();
 611
 612         asprintf(&envp[0], "NETNAME=%s", netname ? : "");
 613         asprintf(&envp[1], "DEVICE=%s", device ? : "");
 614         asprintf(&envp[2], "INTERFACE=%s", interface ? : "");
 615         asprintf(&envp[3], "NAME=%s", myself->name);
 616         envp[4] = NULL;
 617
 618         execute_script("tinc-down", envp);
 619
 620         for(i = 0; i < 4; i++)
 621                 free(envp[i]);
 622
 623         close_device();
 624
 625         return;
 626 }