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

   1 /*
   2     tincctl.c -- Controlling a running tincd
   3     Copyright (C) 2007-2009 Guus Sliepen <guus@tinc-vpn.org>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License along
  16     with this program; if not, write to the Free Software Foundation, Inc.,
  17     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "system.h"
  21
  22 #include <sys/un.h>
  23 #include <getopt.h>
  24
  25 #include "xalloc.h"
  26 #include "protocol.h"
  27 #include "control_common.h"
  28 #include "rsagen.h"
  29
  30 /* The name this program was run with. */
  31 char *program_name = NULL;
  32
  33 /* If nonzero, display usage information and exit. */
  34 bool show_help = false;
  35
  36 /* If nonzero, print the version on standard output and exit.  */
  37 bool show_version = false;
  38
  39 /* If nonzero, it will attempt to kill a running tincd and exit. */
  40 int kill_tincd = 0;
  41
  42 /* If nonzero, generate public/private keypair for this host/net. */
  43 int generate_keys = 0;
  44
  45 static char *identname = NULL;                          /* program name for syslog */
  46 static char *controlsocketname = NULL;                  /* pid file location */
  47 char *netname = NULL;
  48 char *confbase = NULL;
  49
  50 static struct option const long_options[] = {
  51         {"config", required_argument, NULL, 'c'},
  52         {"net", required_argument, NULL, 'n'},
  53         {"help", no_argument, NULL, 1},
  54         {"version", no_argument, NULL, 2},
  55         {"controlsocket", required_argument, NULL, 5},
  56         {NULL, 0, NULL, 0}
  57 };
  58
  59 static void usage(bool status) {
  60         if(status)
  61                 fprintf(stderr, "Try `%s --help\' for more information.\n",
  62                                 program_name);
  63         else {
  64                 printf("Usage: %s [options] command\n\n", program_name);
  65                 printf("Valid options are:\n"
  66                                 "  -c, --config=DIR              Read configuration options from DIR.\n"
  67                                 "  -n, --net=NETNAME             Connect to net NETNAME.\n"
  68                                 "      --controlsocket=FILENAME  Open control socket at FILENAME.\n"
  69                                 "      --help                    Display this help and exit.\n"
  70                                 "      --version                 Output version information and exit.\n"
  71                                 "\n"
  72                                 "Valid commands are:\n"
  73                                 "  start                      Start tincd.\n"
  74                                 "  stop                       Stop tincd.\n"
  75                                 "  restart                    Restart tincd.\n"
  76                                 "  reload                     Reload configuration of running tincd.\n"
  77                                 "  pid                        Show PID of currently running tincd.\n"
  78                                 "  generate-keys [bits]       Generate a new public/private keypair.\n"
  79                                 "  dump                       Dump a list of one of the following things:\n"
  80                                 "    nodes                    - all known nodes in the VPN\n"
  81                                 "    edges                    - all known connections in the VPN\n"
  82                                 "    subnets                  - all known subnets in the VPN\n"
  83                                 "    connections              - all meta connections with ourself\n"
  84                                 "    graph                    - graph of the VPN in dotty format\n"
  85                                 "  purge                      Purge unreachable nodes\n"
  86                                 "  debug N                    Set debug level\n"
  87                                 "  retry                      Retry all outgoing connections\n"
  88                                 "  reload                     Partial reload of configuration\n"
  89                                 "\n");
  90                 printf("Report bugs to tinc@tinc-vpn.org.\n");
  91         }
  92 }
  93
  94 static bool parse_options(int argc, char **argv) {
  95         int r;
  96         int option_index = 0;
  97
  98         while((r = getopt_long(argc, argv, "c:n:", long_options, &option_index)) != EOF) {
  99                 switch (r) {
 100                         case 0:                         /* long option */
 101                                 break;
 102
 103                         case 'c':                               /* config file */
 104                                 confbase = xstrdup(optarg);
 105                                 break;
 106
 107                         case 'n':                               /* net name given */
 108                                 netname = xstrdup(optarg);
 109                                 break;
 110
 111                         case 1:                                 /* show help */
 112                                 show_help = true;
 113                                 break;
 114
 115                         case 2:                                 /* show version */
 116                                 show_version = true;
 117                                 break;
 118
 119                         case 5:                                 /* open control socket here */
 120                                 controlsocketname = xstrdup(optarg);
 121                                 break;
 122
 123                         case '?':
 124                                 usage(true);
 125                                 return false;
 126
 127                         default:
 128                                 break;
 129                 }
 130         }
 131
 132         return true;
 133 }
 134
 135 FILE *ask_and_open(const char *filename, const char *what, const char *mode) {
 136         FILE *r;
 137         char *directory;
 138         char buf[PATH_MAX];
 139         char buf2[PATH_MAX];
 140         size_t len;
 141
 142         /* Check stdin and stdout */
 143         if(isatty(0) && isatty(1)) {
 144                 /* Ask for a file and/or directory name. */
 145                 fprintf(stdout, "Please enter a file to save %s to [%s]: ",
 146                                 what, filename);
 147                 fflush(stdout);
 148
 149                 if(fgets(buf, sizeof buf, stdin) < 0) {
 150                         fprintf(stderr, "Error while reading stdin: %s\n",
 151                                         strerror(errno));
 152                         return NULL;
 153                 }
 154
 155                 len = strlen(buf);
 156                 if(len)
 157                         buf[--len] = 0;
 158
 159                 if(len)
 160                         filename = buf;
 161         }
 162
 163 #ifdef HAVE_MINGW
 164         if(filename[0] != '\\' && filename[0] != '/' && !strchr(filename, ':')) {
 165 #else
 166         if(filename[0] != '/') {
 167 #endif
 168                 /* The directory is a relative path or a filename. */
 169                 directory = get_current_dir_name();
 170                 snprintf(buf2, sizeof buf2, "%s/%s", directory, filename);
 171                 filename = buf2;
 172         }
 173
 174         umask(0077);                            /* Disallow everything for group and other */
 175
 176         /* Open it first to keep the inode busy */
 177
 178         r = fopen(filename, mode);
 179
 180         if(!r) {
 181                 fprintf(stderr, "Error opening file `%s': %s\n", filename, strerror(errno));
 182                 return NULL;
 183         }
 184
 185         return r;
 186 }
 187
 188 /*
 189   Generate a public/private RSA keypair, and ask for a file to store
 190   them in.
 191 */
 192 static bool keygen(int bits) {
 193         rsa_t key;
 194         FILE *f;
 195         char *name = NULL;
 196         char *filename;
 197
 198         fprintf(stderr, "Generating %d bits keys:\n", bits);
 199
 200         if(!rsa_generate(&key, bits, 0x10001)) {
 201                 fprintf(stderr, "Error during key generation!\n");
 202                 return false;
 203         } else
 204                 fprintf(stderr, "Done.\n");
 205
 206         xasprintf(&filename, "%s/rsa_key.priv", confbase);
 207         f = ask_and_open(filename, "private RSA key", "a");
 208
 209         if(!f)
 210                 return false;
 211
 212 #ifdef HAVE_FCHMOD
 213         /* Make it unreadable for others. */
 214         fchmod(fileno(f), 0600);
 215 #endif
 216
 217         if(ftell(f))
 218                 fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
 219
 220         rsa_write_pem_private_key(&key, f);
 221
 222         fclose(f);
 223         free(filename);
 224
 225         if(name)
 226                 xasprintf(&filename, "%s/hosts/%s", confbase, name);
 227         else
 228                 xasprintf(&filename, "%s/rsa_key.pub", confbase);
 229
 230         f = ask_and_open(filename, "public RSA key", "a");
 231
 232         if(!f)
 233                 return false;
 234
 235         if(ftell(f))
 236                 fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
 237
 238         rsa_write_pem_public_key(&key, f);
 239
 240         fclose(f);
 241         free(filename);
 242
 243         return true;
 244 }
 245
 246 /*
 247   Set all files and paths according to netname
 248 */
 249 static void make_names(void) {
 250 #ifdef HAVE_MINGW
 251         HKEY key;
 252         char installdir[1024] = "";
 253         long len = sizeof installdir;
 254 #endif
 255
 256         if(netname)
 257                 xasprintf(&identname, "tinc.%s", netname);
 258         else
 259                 identname = xstrdup("tinc");
 260
 261 #ifdef HAVE_MINGW
 262         if(!RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\tinc", 0, KEY_READ, &key)) {
 263                 if(!RegQueryValueEx(key, NULL, 0, 0, installdir, &len)) {
 264                         if(!logfilename)
 265                                 xasprintf(&logfilename, "%s/log/%s.log", identname);
 266                         if(!confbase) {
 267                                 if(netname)
 268                                         xasprintf(&confbase, "%s/%s", installdir, netname);
 269                                 else
 270                                         xasprintf(&confbase, "%s", installdir);
 271                         }
 272                 }
 273                 RegCloseKey(key);
 274                 if(*installdir)
 275                         return;
 276         }
 277 #endif
 278
 279         if(!controlsocketname)
 280                 xasprintf(&controlsocketname, "%s/run/%s.control/socket", LOCALSTATEDIR, identname);
 281
 282         if(netname) {
 283                 if(!confbase)
 284                         xasprintf(&confbase, CONFDIR "/tinc/%s", netname);
 285                 else
 286                         fprintf(stderr, "Both netname and configuration directory given, using the latter...\n");
 287         } else {
 288                 if(!confbase)
 289                         xasprintf(&confbase, CONFDIR "/tinc");
 290         }
 291 }
 292
 293 static int fullread(int fd, void *data, size_t datalen) {
 294         int rv, len = 0;
 295
 296         while(len < datalen) {
 297                 rv = read(fd, data + len, datalen - len);
 298                 if(rv == -1 && errno == EINTR)
 299                         continue;
 300                 else if(rv == -1)
 301                         return rv;
 302                 else if(rv == 0) {
 303                         errno = ENODATA;
 304                         return -1;
 305                 }
 306                 len += rv;
 307         }
 308         return 0;
 309 }
 310
 311 /*
 312    Send a request (raw)
 313 */
 314 static int send_ctl_request(int fd, enum request_type type,
 315                                                    void const *outdata, size_t outdatalen,
 316                                                    int *res_errno_p, void **indata_p,
 317                                                    size_t *indatalen_p) {
 318         tinc_ctl_request_t req;
 319         int rv;
 320         struct iovec vector[2] = {
 321                 {&req, sizeof req},
 322                 {(void*) outdata, outdatalen}
 323         };
 324         void *indata;
 325
 326         if(res_errno_p == NULL)
 327                 return -1;
 328
 329         memset(&req, 0, sizeof req);
 330         req.length = sizeof req + outdatalen;
 331         req.type = type;
 332         req.res_errno = 0;
 333
 334         while((rv = writev(fd, vector, 2)) == -1 && errno == EINTR) ;
 335         if(rv != req.length)
 336                 return -1;
 337
 338         if(fullread(fd, &req, sizeof req) == -1)
 339                 return -1;
 340
 341         if(req.length < sizeof req) {
 342                 errno = EINVAL;
 343                 return -1;
 344         }
 345
 346         if(req.length > sizeof req) {
 347                 if(indata_p == NULL) {
 348                         errno = EINVAL;
 349                         return -1;
 350                 }
 351
 352                 indata = xmalloc(req.length - sizeof req);
 353
 354                 if(fullread(fd, indata, req.length - sizeof req) == -1) {
 355                         free(indata);
 356                         return -1;
 357                 }
 358
 359                 *indata_p = indata;
 360                 if(indatalen_p != NULL)
 361                         *indatalen_p = req.length - sizeof req;
 362         }
 363
 364         *res_errno_p = req.res_errno;
 365
 366         return 0;
 367 }
 368
 369 /*
 370    Send a request (with printfs)
 371 */
 372 static int send_ctl_request_cooked(int fd, enum request_type type, void const *outdata, size_t outdatalen) {
 373         int res_errno = -1;
 374         char *buf = NULL;
 375         size_t buflen = 0;
 376
 377         if(send_ctl_request(fd, type, outdata, outdatalen, &res_errno,
 378                                                 (void**) &buf, &buflen)) {
 379                 fprintf(stderr, "Error sending request: %s\n", strerror(errno));
 380                 return -1;
 381         }
 382
 383         if(buf != NULL) {
 384                 printf("%*s", (int)buflen, buf);
 385                 free(buf);
 386         }
 387
 388         if(res_errno != 0) {
 389                 fprintf(stderr, "Server reported error: %s\n", strerror(res_errno));
 390                 return -1;
 391         }
 392
 393         return 0;
 394 }
 395
 396 int main(int argc, char *argv[], char *envp[]) {
 397         struct sockaddr_un addr;
 398         tinc_ctl_greeting_t greeting;
 399         int fd;
 400         int result;
 401
 402         program_name = argv[0];
 403
 404         if(!parse_options(argc, argv))
 405                 return 1;
 406
 407         make_names();
 408
 409         if(show_version) {
 410                 printf("%s version %s (built %s %s, protocol %d)\n", PACKAGE,
 411                            VERSION, __DATE__, __TIME__, PROT_CURRENT);
 412                 printf("Copyright (C) 1998-2009 Ivo Timmermans, Guus Sliepen and others.\n"
 413                                 "See the AUTHORS file for a complete list.\n\n"
 414                                 "tinc comes with ABSOLUTELY NO WARRANTY.  This is free software,\n"
 415                                 "and you are welcome to redistribute it under certain conditions;\n"
 416                                 "see the file COPYING for details.\n");
 417
 418                 return 0;
 419         }
 420
 421         if(show_help) {
 422                 usage(false);
 423                 return 0;
 424         }
 425
 426         if(optind >= argc) {
 427                 fprintf(stderr, "Not enough arguments.\n");
 428                 usage(true);
 429                 return 1;
 430         }
 431
 432         // First handle commands that don't involve connecting to a running tinc daemon.
 433
 434         if(!strcasecmp(argv[optind], "generate-keys")) {
 435                 return !keygen(optind > argc ? atoi(argv[optind + 1]) : 2048);
 436         }
 437
 438         if(!strcasecmp(argv[optind], "start")) {
 439                 argv[optind] = NULL;
 440                 execve(SBINDIR "/tincd", argv, envp);
 441                 fprintf(stderr, "Could not start tincd: %s", strerror(errno));
 442                 return 1;
 443         }
 444
 445         /*
 446          * Now handle commands that do involve connecting to a running tinc daemon.
 447          * Authenticate the server by ensuring the parent directory can be
 448          * traversed only by root. Note this is not totally race-free unless all
 449          * ancestors are writable only by trusted users, which we don't verify.
 450          */
 451
 452         struct stat statbuf;
 453         char *lastslash = strrchr(controlsocketname, '/');
 454         if(lastslash != NULL) {
 455                 /* control socket is not in cwd; stat its parent */
 456                 *lastslash = 0;
 457                 result = stat(controlsocketname, &statbuf);
 458                 *lastslash = '/';
 459         } else
 460                 result = stat(".", &statbuf);
 461
 462         if(result < 0) {
 463                 fprintf(stderr, "Unable to check control socket directory permissions: %s\n", strerror(errno));
 464                 return 1;
 465         }
 466
 467         if(statbuf.st_uid != 0 || (statbuf.st_mode & S_IXOTH) != 0 || (statbuf.st_gid != 0 && (statbuf.st_mode & S_IXGRP)) != 0) {
 468                 fprintf(stderr, "Insecure permissions on control socket directory\n");
 469                 return 1;
 470         }
 471
 472         if(strlen(controlsocketname) >= sizeof addr.sun_path) {
 473                 fprintf(stderr, "Control socket filename too long!\n");
 474                 return 1;
 475         }
 476
 477         fd = socket(PF_UNIX, SOCK_STREAM, 0);
 478         if(fd < 0) {
 479                 fprintf(stderr, "Cannot create UNIX socket: %s\n", strerror(errno));
 480                 return 1;
 481         }
 482
 483         memset(&addr, 0, sizeof addr);
 484         addr.sun_family = AF_UNIX;
 485         strncpy(addr.sun_path, controlsocketname, sizeof addr.sun_path - 1);
 486
 487         if(connect(fd, (struct sockaddr *)&addr, sizeof addr) < 0) {
 488                 fprintf(stderr, "Cannot connect to %s: %s\n", controlsocketname, strerror(errno));
 489                 return 1;
 490         }
 491
 492         if(fullread(fd, &greeting, sizeof greeting) == -1) {
 493                 fprintf(stderr, "Cannot read greeting from control socket: %s\n",
 494                                 strerror(errno));
 495                 return 1;
 496         }
 497
 498         if(greeting.version != TINC_CTL_VERSION_CURRENT) {
 499                 fprintf(stderr, "Version mismatch: server %d, client %d\n",
 500                                 greeting.version, TINC_CTL_VERSION_CURRENT);
 501                 return 1;
 502         }
 503
 504         if(!strcasecmp(argv[optind], "pid")) {
 505                 printf("%d\n", greeting.pid);
 506                 return 0;
 507         }
 508
 509         if(!strcasecmp(argv[optind], "stop")) {
 510                 return send_ctl_request_cooked(fd, REQ_STOP, NULL, 0) != -1;
 511         }
 512
 513         if(!strcasecmp(argv[optind], "reload")) {
 514                 return send_ctl_request_cooked(fd, REQ_RELOAD, NULL, 0) != -1;
 515         }
 516
 517         if(!strcasecmp(argv[optind], "restart")) {
 518                 return send_ctl_request_cooked(fd, REQ_RESTART, NULL, 0) != -1;
 519         }
 520
 521         if(!strcasecmp(argv[optind], "dump")) {
 522                 if(argc < optind + 2) {
 523                         fprintf(stderr, "Not enough arguments.\n");
 524                         usage(true);
 525                         return 1;
 526                 }
 527
 528                 if(!strcasecmp(argv[optind+1], "nodes")) {
 529                         return send_ctl_request_cooked(fd, REQ_DUMP_NODES, NULL, 0) != -1;
 530                 }
 531
 532                 if(!strcasecmp(argv[optind+1], "edges")) {
 533                         return send_ctl_request_cooked(fd, REQ_DUMP_EDGES, NULL, 0) != -1;
 534                 }
 535
 536                 if(!strcasecmp(argv[optind+1], "subnets")) {
 537                         return send_ctl_request_cooked(fd, REQ_DUMP_SUBNETS, NULL, 0) != -1;
 538                 }
 539
 540                 if(!strcasecmp(argv[optind+1], "connections")) {
 541                         return send_ctl_request_cooked(fd, REQ_DUMP_CONNECTIONS, NULL, 0) != -1;
 542                 }
 543
 544                 if(!strcasecmp(argv[optind+1], "graph")) {
 545                         return send_ctl_request_cooked(fd, REQ_DUMP_GRAPH, NULL, 0) != -1;
 546                 }
 547
 548                 fprintf(stderr, "Unknown dump type '%s'.\n", argv[optind+1]);
 549                 usage(true);
 550                 return 1;
 551         }
 552
 553         if(!strcasecmp(argv[optind], "purge")) {
 554                 return send_ctl_request_cooked(fd, REQ_PURGE, NULL, 0) != -1;
 555         }
 556
 557         if(!strcasecmp(argv[optind], "debug")) {
 558                 int debuglevel;
 559
 560                 if(argc != optind + 2) {
 561                         fprintf(stderr, "Invalid arguments.\n");
 562                         return 1;
 563                 }
 564                 debuglevel = atoi(argv[optind+1]);
 565                 return send_ctl_request_cooked(fd, REQ_SET_DEBUG, &debuglevel,
 566                                                                            sizeof debuglevel) != -1;
 567         }
 568
 569         if(!strcasecmp(argv[optind], "retry")) {
 570                 return send_ctl_request_cooked(fd, REQ_RETRY, NULL, 0) != -1;
 571         }
 572
 573         if(!strcasecmp(argv[optind], "reload")) {
 574                 return send_ctl_request_cooked(fd, REQ_RELOAD, NULL, 0) != -1;
 575         }
 576
 577         fprintf(stderr, "Unknown command `%s'.\n", argv[optind]);
 578         usage(true);
 579
 580         close(fd);
 581
 582         return 0;
 583 }