tinc-vpn.org Git - tinc/blob - src/net_setup.c

   1 /*
   2     net_setup.c -- Setup.
   3     Copyright (C) 1998-2005 Ivo Timmermans,
   4                   2000-2010 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
  49 bool read_rsa_public_key(connection_t *c) {
  50         FILE *fp;
  51         char *fname;
  52         char *key;
  53
  54         if(!c->rsa_key) {
  55                 c->rsa_key = RSA_new();
  56 //              RSA_blinding_on(c->rsa_key, NULL);
  57         }
  58
  59         /* First, check for simple PublicKey statement */
  60
  61         if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
  62                 BN_hex2bn(&c->rsa_key->n, key);
  63                 BN_hex2bn(&c->rsa_key->e, "FFFF");
  64                 free(key);
  65                 return true;
  66         }
  67
  68         /* Else, check for PublicKeyFile statement and read it */
  69
  70         if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
  71                 fp = fopen(fname, "r");
  72
  73                 if(!fp) {
  74                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  75                                    fname, strerror(errno));
  76                         free(fname);
  77                         return false;
  78                 }
  79
  80                 free(fname);
  81                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
  82                 fclose(fp);
  83
  84                 if(c->rsa_key)
  85                         return true;            /* Woohoo. */
  86
  87                 /* If it fails, try PEM_read_RSA_PUBKEY. */
  88                 fp = fopen(fname, "r");
  89
  90                 if(!fp) {
  91                         logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
  92                                    fname, strerror(errno));
  93                         free(fname);
  94                         return false;
  95                 }
  96
  97                 free(fname);
  98                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
  99                 fclose(fp);
 100
 101                 if(c->rsa_key) {
 102 //                              RSA_blinding_on(c->rsa_key, NULL);
 103                         return true;
 104                 }
 105
 106                 logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s",
 107                            fname, strerror(errno));
 108                 return false;
 109         }
 110
 111         /* Else, check if a harnessed public key is in the config file */
 112
 113         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 114         fp = fopen(fname, "r");
 115
 116         if(fp) {
 117                 c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 118                 fclose(fp);
 119         }
 120
 121         free(fname);
 122
 123         if(c->rsa_key)
 124                 return true;
 125
 126         /* Try again with PEM_read_RSA_PUBKEY. */
 127
 128         xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
 129         fp = fopen(fname, "r");
 130
 131         if(fp) {
 132                 c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 133 //              RSA_blinding_on(c->rsa_key, NULL);
 134                 fclose(fp);
 135         }
 136
 137         free(fname);
 138
 139         if(c->rsa_key)
 140                 return true;
 141
 142         logger(LOG_ERR, "No public key for %s specified!", c->name);
 143
 144         return false;
 145 }
 146
 147 bool read_rsa_private_key(void) {
 148         FILE *fp;
 149         char *fname, *key, *pubkey;
 150         struct stat s;
 151
 152         if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
 153                 if(!get_config_string(lookup_config(config_tree, "PublicKey"), &pubkey)) {
 154                         logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
 155                         return false;
 156                 }
 157                 myself->connection->rsa_key = RSA_new();
 158 //              RSA_blinding_on(myself->connection->rsa_key, NULL);
 159                 BN_hex2bn(&myself->connection->rsa_key->d, key);
 160                 BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
 161                 BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
 162                 free(key);
 163                 free(pubkey);
 164                 return true;
 165         }
 166
 167         if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
 168                 xasprintf(&fname, "%s/rsa_key.priv", confbase);
 169
 170         fp = fopen(fname, "r");
 171
 172         if(!fp) {
 173                 logger(LOG_ERR, "Error reading RSA private key file `%s': %s",
 174                            fname, strerror(errno));
 175                 free(fname);
 176                 return false;
 177         }
 178
 179 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
 180         if(fstat(fileno(fp), &s)) {
 181                 logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
 182                                 fname, strerror(errno));
 183                 free(fname);
 184                 return false;
 185         }
 186
 187         if(s.st_mode & ~0100700)
 188                 logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
 189 #endif
 190
 191         myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 192         fclose(fp);
 193
 194         if(!myself->connection->rsa_key) {
 195                 logger(LOG_ERR, "Reading RSA private key file `%s' failed: %s",
 196                            fname, strerror(errno));
 197                 free(fname);
 198                 return false;
 199         }
 200
 201         free(fname);
 202         return true;
 203 }
 204
 205 /*
 206   Read Subnets from all host config files
 207 */
 208 void load_all_subnets(void) {
 209         DIR *dir;
 210         struct dirent *ent;
 211         char *dname;
 212         char *fname;
 213         avl_tree_t *config_tree;
 214         config_t *cfg;
 215         subnet_t *s, *s2;
 216         node_t *n;
 217         bool result;
 218
 219         xasprintf(&dname, "%s/hosts", confbase);
 220         dir = opendir(dname);
 221         if(!dir) {
 222                 logger(LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 223                 free(dname);
 224                 return;
 225         }
 226
 227         while((ent = readdir(dir))) {
 228                 if(!check_id(ent->d_name))
 229                         continue;
 230
 231                 n = lookup_node(ent->d_name);
 232                 #ifdef _DIRENT_HAVE_D_TYPE
 233                 //if(ent->d_type != DT_REG)
 234                 //      continue;
 235                 #endif
 236
 237                 xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 238                 init_configuration(&config_tree);
 239                 result = read_config_file(config_tree, fname);
 240                 free(fname);
 241                 if(!result)
 242                         continue;
 243
 244                 if(!n) {
 245                         n = new_node();
 246                         n->name = xstrdup(ent->d_name);
 247                         node_add(n);
 248                 }
 249
 250                 for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
 251                         if(!get_config_subnet(cfg, &s))
 252                                 continue;
 253
 254                         if((s2 = lookup_subnet(n, s))) {
 255                                 s2->expires = -1;
 256                         } else {
 257                                 subnet_add(n, s);
 258                         }
 259                 }
 260
 261                 exit_configuration(&config_tree);
 262         }
 263
 264         closedir(dir);
 265 }
 266
 267 /*
 268   Configure node_t myself and set up the local sockets (listen only)
 269 */
 270 bool setup_myself(void) {
 271         config_t *cfg;
 272         subnet_t *subnet;
 273         char *name, *hostname, *mode, *afname, *cipher, *digest;
 274         char *fname = NULL;
 275         char *address = NULL;
 276         char *envp[5];
 277         struct addrinfo *ai, *aip, hint = {0};
 278         bool choice;
 279         int i, err;
 280         int replaywin_int;
 281
 282         myself = new_node();
 283         myself->connection = new_connection();
 284
 285         myself->hostname = xstrdup("MYSELF");
 286         myself->connection->hostname = xstrdup("MYSELF");
 287
 288         myself->connection->options = 0;
 289         myself->connection->protocol_version = PROT_CURRENT;
 290
 291         if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
 292                 logger(LOG_ERR, "Name for tinc daemon required!");
 293                 return false;
 294         }
 295
 296         if(!check_id(name)) {
 297                 logger(LOG_ERR, "Invalid name for myself!");
 298                 free(name);
 299                 return false;
 300         }
 301
 302         myself->name = name;
 303         myself->connection->name = xstrdup(name);
 304         xasprintf(&fname, "%s/hosts/%s", confbase, name);
 305         read_config_options(config_tree, name);
 306         read_config_file(config_tree, fname);
 307         free(fname);
 308
 309         if(!read_rsa_private_key())
 310                 return false;
 311
 312         if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
 313                 myport = xstrdup("655");
 314
 315         if(!atoi(myport)) {
 316                 struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
 317                 sockaddr_t sa;
 318                 if(!ai || !ai->ai_addr)
 319                         return false;
 320                 free(myport);
 321                 memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
 322                 sockaddr2str(&sa, NULL, &myport);
 323         }
 324
 325         /* Read in all the subnets specified in the host configuration file */
 326
 327         cfg = lookup_config(config_tree, "Subnet");
 328
 329         while(cfg) {
 330                 if(!get_config_subnet(cfg, &subnet))
 331                         return false;
 332
 333                 subnet_add(myself, subnet);
 334
 335                 cfg = lookup_config_next(config_tree, cfg);
 336         }
 337
 338         /* Check some options */
 339
 340         if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
 341                 myself->options |= OPTION_INDIRECT;
 342
 343         if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
 344                 myself->options |= OPTION_TCPONLY;
 345
 346         if(myself->options & OPTION_TCPONLY)
 347                 myself->options |= OPTION_INDIRECT;
 348
 349         get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 350         get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 351         get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
 352         strictsubnets |= tunnelserver;
 353
 354         if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
 355                 if(!strcasecmp(mode, "router"))
 356                         routing_mode = RMODE_ROUTER;
 357                 else if(!strcasecmp(mode, "switch"))
 358                         routing_mode = RMODE_SWITCH;
 359                 else if(!strcasecmp(mode, "hub"))
 360                         routing_mode = RMODE_HUB;
 361                 else {
 362                         logger(LOG_ERR, "Invalid routing mode!");
 363                         return false;
 364                 }
 365                 free(mode);
 366         }
 367
 368         if(get_config_string(lookup_config(config_tree, "Forwarding"), &mode)) {
 369                 if(!strcasecmp(mode, "off"))
 370                         forwarding_mode = FMODE_OFF;
 371                 else if(!strcasecmp(mode, "internal"))
 372                         forwarding_mode = FMODE_INTERNAL;
 373                 else if(!strcasecmp(mode, "kernel"))
 374                         forwarding_mode = FMODE_KERNEL;
 375                 else {
 376                         logger(LOG_ERR, "Invalid forwarding mode!");
 377                         return false;
 378                 }
 379                 free(mode);
 380         }
 381
 382         choice = true;
 383         get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
 384         if(choice)
 385                 myself->options |= OPTION_PMTU_DISCOVERY;
 386
 387         choice = true;
 388         get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
 389         if(choice)
 390                 myself->options |= OPTION_CLAMP_MSS;
 391
 392         get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
 393
 394 #if !defined(SOL_IP) || !defined(IP_TOS)
 395         if(priorityinheritance)
 396                 logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
 397 #endif
 398
 399         if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
 400                 macexpire = 600;
 401
 402         if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
 403                 if(maxtimeout <= 0) {
 404                         logger(LOG_ERR, "Bogus maximum timeout!");
 405                         return false;
 406                 }
 407         } else
 408                 maxtimeout = 900;
 409
 410         if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 411                 if(udp_rcvbuf <= 0) {
 412                         logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
 413                         return false;
 414                 }
 415         }
 416
 417         if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
 418                 if(udp_sndbuf <= 0) {
 419                         logger(LOG_ERR, "UDPSndBuf cannot be negative!");
 420                         return false;
 421                 }
 422         }
 423
 424         if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
 425                 if(replaywin_int < 0) {
 426                         logger(LOG_ERR, "ReplayWindow cannot be negative!");
 427                         return false;
 428                 }
 429                 replaywin = (unsigned)replaywin_int;
 430         }
 431
 432         if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
 433                 if(!strcasecmp(afname, "IPv4"))
 434                         addressfamily = AF_INET;
 435                 else if(!strcasecmp(afname, "IPv6"))
 436                         addressfamily = AF_INET6;
 437                 else if(!strcasecmp(afname, "any"))
 438                         addressfamily = AF_UNSPEC;
 439                 else {
 440                         logger(LOG_ERR, "Invalid address family!");
 441                         return false;
 442                 }
 443                 free(afname);
 444         }
 445
 446         get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 447
 448         /* Generate packet encryption key */
 449
 450         if(get_config_string
 451            (lookup_config(config_tree, "Cipher"), &cipher)) {
 452                 if(!strcasecmp(cipher, "none")) {
 453                         myself->incipher = NULL;
 454                 } else {
 455                         myself->incipher = EVP_get_cipherbyname(cipher);
 456
 457                         if(!myself->incipher) {
 458                                 logger(LOG_ERR, "Unrecognized cipher type!");
 459                                 return false;
 460                         }
 461                 }
 462         } else
 463                 myself->incipher = EVP_bf_cbc();
 464
 465         if(myself->incipher)
 466                 myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
 467         else
 468                 myself->inkeylength = 1;
 469
 470         myself->connection->outcipher = EVP_bf_ofb();
 471
 472         if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 473                 keylifetime = 3600;
 474
 475         keyexpires = now + keylifetime;
 476
 477         /* Check if we want to use message authentication codes... */
 478
 479         if(get_config_string(lookup_config(config_tree, "Digest"), &digest)) {
 480                 if(!strcasecmp(digest, "none")) {
 481                         myself->indigest = NULL;
 482                 } else {
 483                         myself->indigest = EVP_get_digestbyname(digest);
 484
 485                         if(!myself->indigest) {
 486                                 logger(LOG_ERR, "Unrecognized digest type!");
 487                                 return false;
 488                         }
 489                 }
 490         } else
 491                 myself->indigest = EVP_sha1();
 492
 493         myself->connection->outdigest = EVP_sha1();
 494
 495         if(get_config_int(lookup_config(config_tree, "MACLength"), &myself->inmaclength)) {
 496                 if(myself->indigest) {
 497                         if(myself->inmaclength > myself->indigest->md_size) {
 498                                 logger(LOG_ERR, "MAC length exceeds size of digest!");
 499                                 return false;
 500                         } else if(myself->inmaclength < 0) {
 501                                 logger(LOG_ERR, "Bogus MAC length!");
 502                                 return false;
 503                         }
 504                 }
 505         } else
 506                 myself->inmaclength = 4;
 507
 508         myself->connection->outmaclength = 0;
 509
 510         /* Compression */
 511
 512         if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
 513                 if(myself->incompression < 0 || myself->incompression > 11) {
 514                         logger(LOG_ERR, "Bogus compression level!");
 515                         return false;
 516                 }
 517         } else
 518                 myself->incompression = 0;
 519
 520         myself->connection->outcompression = 0;
 521
 522         /* Done */
 523
 524         myself->nexthop = myself;
 525         myself->via = myself;
 526         myself->status.reachable = true;
 527         node_add(myself);
 528
 529         graph();
 530
 531         if(strictsubnets)
 532                 load_all_subnets();
 533
 534         /* Open device */
 535
 536         if(!setup_device())
 537                 return false;
 538
 539         /* Run tinc-up script to further initialize the tap interface */
 540         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 541         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 542         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 543         xasprintf(&envp[3], "NAME=%s", myself->name);
 544         envp[4] = NULL;
 545
 546         execute_script("tinc-up", envp);
 547
 548         for(i = 0; i < 5; i++)
 549                 free(envp[i]);
 550
 551         /* Run subnet-up scripts for our own subnets */
 552
 553         subnet_update(myself, NULL, true);
 554
 555         /* Open sockets */
 556
 557         get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
 558
 559         hint.ai_family = addressfamily;
 560         hint.ai_socktype = SOCK_STREAM;
 561         hint.ai_protocol = IPPROTO_TCP;
 562         hint.ai_flags = AI_PASSIVE;
 563
 564         err = getaddrinfo(address, myport, &hint, &ai);
 565
 566         if(err || !ai) {
 567                 logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
 568                            gai_strerror(err));
 569                 return false;
 570         }
 571
 572         listen_sockets = 0;
 573
 574         for(aip = ai; aip; aip = aip->ai_next) {
 575                 listen_socket[listen_sockets].tcp =
 576                         setup_listen_socket((sockaddr_t *) aip->ai_addr);
 577
 578                 if(listen_socket[listen_sockets].tcp < 0)
 579                         continue;
 580
 581                 listen_socket[listen_sockets].udp =
 582                         setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 583
 584                 if(listen_socket[listen_sockets].udp < 0)
 585                         continue;
 586
 587                 ifdebug(CONNECTIONS) {
 588                         hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
 589                         logger(LOG_NOTICE, "Listening on %s", hostname);
 590                         free(hostname);
 591                 }
 592
 593                 memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
 594                 listen_sockets++;
 595         }
 596
 597         freeaddrinfo(ai);
 598
 599         if(listen_sockets)
 600                 logger(LOG_NOTICE, "Ready");
 601         else {
 602                 logger(LOG_ERR, "Unable to create any listening socket!");
 603                 return false;
 604         }
 605
 606         return true;
 607 }
 608
 609 /*
 610   initialize network
 611 */
 612 bool setup_network(void) {
 613         now = time(NULL);
 614
 615         init_events();
 616         init_connections();
 617         init_subnets();
 618         init_nodes();
 619         init_edges();
 620         init_requests();
 621
 622         if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
 623                 if(pinginterval < 1) {
 624                         pinginterval = 86400;
 625                 }
 626         } else
 627                 pinginterval = 60;
 628
 629         if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
 630                 pingtimeout = 5;
 631         if(pingtimeout < 1 || pingtimeout > pinginterval)
 632                 pingtimeout = pinginterval;
 633
 634         if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
 635                 maxoutbufsize = 10 * MTU;
 636
 637         if(!setup_myself())
 638                 return false;
 639
 640         return true;
 641 }
 642
 643 /*
 644   close all open network connections
 645 */
 646 void close_network_connections(void) {
 647         avl_node_t *node, *next;
 648         connection_t *c;
 649         char *envp[5];
 650         int i;
 651
 652         for(node = connection_tree->head; node; node = next) {
 653                 next = node->next;
 654                 c = node->data;
 655                 c->outgoing = NULL;
 656                 terminate_connection(c, false);
 657         }
 658
 659         for(list_node_t *node = outgoing_list->head; node; node = node->next) {
 660                 outgoing_t *outgoing = node->data;
 661
 662                 if(outgoing->event)
 663                         event_del(outgoing->event);
 664         }
 665
 666         list_delete_list(outgoing_list);
 667
 668         if(myself && myself->connection) {
 669                 subnet_update(myself, NULL, false);
 670                 terminate_connection(myself->connection, false);
 671                 free_connection(myself->connection);
 672         }
 673
 674         for(i = 0; i < listen_sockets; i++) {
 675                 close(listen_socket[i].tcp);
 676                 close(listen_socket[i].udp);
 677         }
 678
 679         xasprintf(&envp[0], "NETNAME=%s", netname ? : "");
 680         xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 681         xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 682         xasprintf(&envp[3], "NAME=%s", myself->name);
 683         envp[4] = NULL;
 684
 685         exit_requests();
 686         exit_edges();
 687         exit_subnets();
 688         exit_nodes();
 689         exit_connections();
 690         exit_events();
 691
 692         execute_script("tinc-down", envp);
 693
 694         if(myport) free(myport);
 695
 696         for(i = 0; i < 4; i++)
 697                 free(envp[i]);
 698
 699         close_device();
 700
 701         return;
 702 }