src/charon/daemon.c

   1 /*
   2  * Copyright (C) 2006-2007 Tobias Brunner
   3  * Copyright (C) 2006 Daniel Roethlisberger
   4  * Copyright (C) 2005-2008 Martin Willi
   5  * Copyright (C) 2005 Jan Hutter
   6  * Hochschule fuer Technik Rapperswil
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * for more details.
  17  */
  18
  19 #include <stdio.h>
  20 #include <linux/capability.h>
  21 #include <sys/prctl.h>
  22 #include <signal.h>
  23 #include <pthread.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <unistd.h>
  27 #include <time.h>
  28 #include <string.h>
  29 #include <getopt.h>
  30 #include <errno.h>
  31 #ifdef HAVE_BACKTRACE
  32 # include <execinfo.h>
  33 #endif /* HAVE_BACKTRACE */
  34
  35 #include "daemon.h"
  36
  37 #include <library.h>
  38 #include <config/traffic_selector.h>
  39
  40 /* on some distros, a capset definition is missing */
  41 #ifdef NO_CAPSET_DEFINED
  42 extern int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
  43 #endif /* NO_CAPSET_DEFINED */
  44
  45 #ifdef INTEGRITY_TEST
  46 #include <fips/fips.h>
  47 #include <fips_signature.h>
  48 #endif /* INTEGRITY_TEST */
  49
  50 typedef struct private_daemon_t private_daemon_t;
  51
  52 /**
  53  * Private additions to daemon_t, contains threads and internal functions.
  54  */
  55 struct private_daemon_t {
  56         /**
  57          * Public members of daemon_t.
  58          */
  59         daemon_t public;
  60
  61         /**
  62          * Signal set used for signal handling.
  63          */
  64         sigset_t signal_set;
  65
  66         /**
  67          * The thread_id of main-thread.
  68          */
  69         pthread_t main_thread_id;
  70 };
  71
  72 /**
  73  * One and only instance of the daemon.
  74  */
  75 daemon_t *charon;
  76
  77 /**
  78  * hook in library for debugging messages
  79  */
  80 extern void (*dbg) (int level, char *fmt, ...);
  81
  82 /**
  83  * Logging hook for library logs, spreads debug message over bus
  84  */
  85 static void dbg_bus(int level, char *fmt, ...)
  86 {
  87         va_list args;
  88
  89         va_start(args, fmt);
  90         charon->bus->vsignal(charon->bus, DBG_LIB, level, fmt, args);
  91         va_end(args);
  92 }
  93 /**
  94  * Logging hook for library logs before logging facility initiated
  95  */
  96 static void dbg_silent(int level, char *fmt, ...)
  97 {
  98 }
  99
 100 /**
 101  * Logging hook for library logs, using stderr output
 102  */
 103 static void dbg_stderr(int level, char *fmt, ...)
 104 {
 105         va_list args;
 106
 107         va_start(args, fmt);
 108         fprintf(stderr, "00[LIB] ");
 109         vfprintf(stderr, fmt, args);
 110         fprintf(stderr, "\n");
 111         va_end(args);
 112 }
 113
 114 /**
 115  * Run the daemon and handle unix signals
 116  */
 117 static void run(private_daemon_t *this)
 118 {
 119         sigset_t set;
 120
 121         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
 122         sigemptyset(&set);
 123         sigaddset(&set, SIGINT);
 124         sigaddset(&set, SIGHUP);
 125         sigaddset(&set, SIGTERM);
 126
 127         while (TRUE)
 128         {
 129                 int sig;
 130                 int error;
 131
 132                 error = sigwait(&set, &sig);
 133                 if (error)
 134                 {
 135                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 136                         return;
 137                 }
 138                 switch (sig)
 139                 {
 140                         case SIGHUP:
 141                         {
 142                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
 143                                 break;
 144                         }
 145                         case SIGINT:
 146                         {
 147                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 148                                 return;
 149                         }
 150                         case SIGTERM:
 151                         {
 152                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 153                                 return;
 154                         }
 155                         default:
 156                         {
 157                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 158                                 break;
 159                         }
 160                 }
 161         }
 162 }
 163
 164 /**
 165  * Clean up all daemon resources
 166  */
 167 static void destroy(private_daemon_t *this)
 168 {
 169         /* terminate all idle threads */
 170         if (this->public.processor)
 171         {
 172                 this->public.processor->set_threads(this->public.processor, 0);
 173         }
 174         /* close all IKE_SAs */
 175         DESTROY_IF(this->public.plugins);
 176         DESTROY_IF(this->public.ike_sa_manager);
 177         DESTROY_IF(this->public.kernel_interface);
 178         DESTROY_IF(this->public.scheduler);
 179         DESTROY_IF(this->public.controller);
 180         DESTROY_IF(this->public.eap);
 181 #ifdef ME
 182         DESTROY_IF(this->public.connect_manager);
 183         DESTROY_IF(this->public.mediation_manager);
 184 #endif /* ME */
 185         DESTROY_IF(this->public.backends);
 186         DESTROY_IF(this->public.attributes);
 187         DESTROY_IF(this->public.credentials);
 188         DESTROY_IF(this->public.sender);
 189         DESTROY_IF(this->public.receiver);
 190         DESTROY_IF(this->public.socket);
 191         /* wait until all threads are gone */
 192         DESTROY_IF(this->public.processor);
 193
 194         /* rehook library logging, shutdown logging */
 195         dbg = dbg_stderr;
 196         DESTROY_IF(this->public.bus);
 197         DESTROY_IF(this->public.outlog);
 198         DESTROY_IF(this->public.syslog);
 199         DESTROY_IF(this->public.authlog);
 200         free(this);
 201 }
 202
 203 /**
 204  * Enforce daemon shutdown, with a given reason to do so.
 205  */
 206 static void kill_daemon(private_daemon_t *this, char *reason)
 207 {
 208         /* we send SIGTERM, so the daemon can cleanly shut down */
 209         DBG1(DBG_DMN, "killing daemon: %s", reason);
 210         if (this->main_thread_id == pthread_self())
 211         {
 212                 /* initialization failed, terminate daemon */
 213                 destroy(this);
 214                 unlink(PID_FILE);
 215                 exit(-1);
 216         }
 217         else
 218         {
 219                 DBG1(DBG_DMN, "sending SIGTERM to ourself");
 220                 raise(SIGTERM);
 221                 /* thread must die, since he produced a ciritcal failure and can't continue */
 222                 pthread_exit(NULL);
 223         }
 224 }
 225
 226 /**
 227  * drop daemon capabilities
 228  */
 229 static void drop_capabilities(private_daemon_t *this, bool full)
 230 {
 231         struct __user_cap_header_struct hdr;
 232         struct __user_cap_data_struct data;
 233
 234         /* CAP_NET_ADMIN is needed to use netlink */
 235         u_int32_t keep = (1<<CAP_NET_ADMIN) | (1<<CAP_SYS_NICE);
 236
 237         if (full)
 238         {
 239 #               if IPSEC_GID
 240                 if (setgid(IPSEC_GID) != 0)
 241                 {
 242                         kill_daemon(this, "changing GID to unprivileged group failed");
 243                 }
 244 #               endif
 245 #               if IPSEC_UID
 246                 if (setuid(IPSEC_UID) != 0)
 247                 {
 248                         kill_daemon(this, "changing UID to unprivileged user failed");
 249                 }
 250 #               endif
 251         }
 252         else
 253         {
 254                 /* CAP_NET_BIND_SERVICE to bind services below port 1024 */
 255                 keep |= (1<<CAP_NET_BIND_SERVICE);
 256                 /* CAP_NET_RAW to create RAW sockets */
 257                 keep |= (1<<CAP_NET_RAW);
 258                 /* CAP_DAC_READ_SEARCH to read ipsec.secrets */
 259                 keep |= (1<<CAP_DAC_READ_SEARCH);
 260                 /* CAP_CHOWN to change file permissions (socket permissions) */
 261                 keep |= (1<<CAP_CHOWN);
 262                 /* CAP_SETUID to call setuid()  */
 263                 keep |= (1<<CAP_SETUID);
 264                 /* CAP_SETGID to call setgid() */
 265                 keep |= (1<<CAP_SETGID);
 266         }
 267
 268         hdr.version = _LINUX_CAPABILITY_VERSION;
 269         hdr.pid = 0;
 270         data.inheritable = data.effective = data.permitted = keep;
 271
 272         if (capset(&hdr, &data))
 273         {
 274                 kill_daemon(this, "unable to drop daemon capabilities");
 275         }
 276 }
 277
 278 /**
 279  * Initialize the daemon
 280  */
 281 static bool initialize(private_daemon_t *this, bool syslog, level_t levels[])
 282 {
 283         signal_t signal;
 284
 285         /* for uncritical pseudo random numbers */
 286         srandom(time(NULL) + getpid());
 287
 288         /* setup bus and it's listeners first to enable log output */
 289         this->public.bus = bus_create();
 290         this->public.outlog = file_logger_create(stdout);
 291         this->public.syslog = sys_logger_create(LOG_DAEMON);
 292         this->public.authlog = sys_logger_create(LOG_AUTHPRIV);
 293         this->public.bus->add_listener(this->public.bus, &this->public.syslog->listener);
 294         this->public.bus->add_listener(this->public.bus, &this->public.outlog->listener);
 295         this->public.bus->add_listener(this->public.bus, &this->public.authlog->listener);
 296         this->public.authlog->set_level(this->public.authlog, SIG_ANY, LEVEL_AUDIT);
 297         /* set up hook to log dbg message in library via charons message bus */
 298         dbg = dbg_bus;
 299
 300         /* apply loglevels */
 301         for (signal = 0; signal < DBG_MAX; signal++)
 302         {
 303                 this->public.syslog->set_level(this->public.syslog,
 304                                                                            signal, levels[signal]);
 305                 if (!syslog)
 306                 {
 307                         this->public.outlog->set_level(this->public.outlog,
 308                                                                                    signal, levels[signal]);
 309                 }
 310         }
 311
 312         DBG1(DBG_DMN, "starting charon (strongSwan Version %s)", VERSION);
 313
 314 #ifdef INTEGRITY_TEST
 315         DBG1(DBG_DMN, "integrity test of libstrongswan code");
 316         if (fips_verify_hmac_signature(hmac_key, hmac_signature))
 317         {
 318                 DBG1(DBG_DMN, "  integrity test passed");
 319         }
 320         else
 321         {
 322                 DBG1(DBG_DMN, "  integrity test failed");
 323                 return FALSE;
 324         }
 325 #endif /* INTEGRITY_TEST */
 326
 327         this->public.ike_sa_manager = ike_sa_manager_create();
 328         if (this->public.ike_sa_manager == NULL)
 329         {
 330                 return FALSE;
 331         }
 332         this->public.processor = processor_create();
 333         this->public.scheduler = scheduler_create();
 334
 335         /* load secrets, ca certificates and crls */
 336         this->public.credentials = credential_manager_create();
 337         this->public.controller = controller_create();
 338         this->public.eap = eap_manager_create();
 339         this->public.backends = backend_manager_create();
 340         this->public.attributes = attribute_manager_create();
 341         this->public.plugins = plugin_loader_create();
 342         this->public.kernel_interface = kernel_interface_create();
 343         this->public.socket = socket_create();
 344         this->public.sender = sender_create();
 345         this->public.receiver = receiver_create();
 346         if (this->public.receiver == NULL)
 347         {
 348                 return FALSE;
 349         }
 350
 351 #ifdef ME
 352         this->public.connect_manager = connect_manager_create();
 353         if (this->public.connect_manager == NULL)
 354         {
 355                 return FALSE;
 356         }
 357         this->public.mediation_manager = mediation_manager_create();
 358 #endif /* ME */
 359
 360         this->public.plugins->load(this->public.plugins, IPSEC_PLUGINDIR, "libcharon-");
 361
 362         return TRUE;
 363 }
 364
 365 /**
 366  * Handle SIGSEGV/SIGILL signals raised by threads
 367  */
 368 static void segv_handler(int signal)
 369 {
 370 #ifdef HAVE_BACKTRACE
 371         void *array[20];
 372         size_t size;
 373         char **strings;
 374         size_t i;
 375
 376         size = backtrace(array, 20);
 377         strings = backtrace_symbols(array, size);
 378
 379         DBG1(DBG_JOB, "thread %u received %s. Dumping %d frames from stack:",
 380                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL", size);
 381
 382         for (i = 0; i < size; i++)
 383         {
 384                 DBG1(DBG_DMN, "    %s", strings[i]);
 385         }
 386         free (strings);
 387 #else /* !HAVE_BACKTRACE */
 388         DBG1(DBG_DMN, "thread %u received %s",
 389                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
 390 #endif /* HAVE_BACKTRACE */
 391         DBG1(DBG_DMN, "killing ourself, received critical signal");
 392         raise(SIGKILL);
 393 }
 394
 395 /**
 396  * Create the daemon.
 397  */
 398 private_daemon_t *daemon_create(void)
 399 {
 400         struct sigaction action;
 401         private_daemon_t *this = malloc_thing(private_daemon_t);
 402
 403         /* assign methods */
 404         this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
 405
 406         /* NULL members for clean destruction */
 407         this->public.socket = NULL;
 408         this->public.ike_sa_manager = NULL;
 409         this->public.credentials = NULL;
 410         this->public.backends = NULL;
 411         this->public.attributes = NULL;
 412         this->public.sender= NULL;
 413         this->public.receiver = NULL;
 414         this->public.scheduler = NULL;
 415         this->public.kernel_interface = NULL;
 416         this->public.processor = NULL;
 417         this->public.controller = NULL;
 418         this->public.eap = NULL;
 419         this->public.plugins = NULL;
 420         this->public.bus = NULL;
 421         this->public.outlog = NULL;
 422         this->public.syslog = NULL;
 423         this->public.authlog = NULL;
 424
 425         this->main_thread_id = pthread_self();
 426
 427         /* add handler for SEGV and ILL,
 428          * add handler for USR1 (cancellation).
 429          * INT, TERM and HUP are handled by sigwait() in run() */
 430         action.sa_handler = segv_handler;
 431         action.sa_flags = 0;
 432         sigemptyset(&action.sa_mask);
 433         sigaddset(&action.sa_mask, SIGINT);
 434         sigaddset(&action.sa_mask, SIGTERM);
 435         sigaddset(&action.sa_mask, SIGHUP);
 436         sigaction(SIGSEGV, &action, NULL);
 437         sigaction(SIGILL, &action, NULL);
 438         action.sa_handler = SIG_IGN;
 439         sigaction(SIGPIPE, &action, NULL);
 440
 441         pthread_sigmask(SIG_SETMASK, &action.sa_mask, 0);
 442
 443         return this;
 444 }
 445
 446 /**
 447  * print command line usage and exit
 448  */
 449 static void usage(const char *msg)
 450 {
 451         if (msg != NULL && *msg != '\0')
 452         {
 453                 fprintf(stderr, "%s\n", msg);
 454         }
 455         fprintf(stderr, "Usage: charon\n"
 456                                         "         [--help]\n"
 457                                         "         [--version]\n"
 458                                         "         [--strictcrlpolicy]\n"
 459                                         "         [--cachecrls]\n"
 460                                         "         [--crlcheckinterval <interval>]\n"
 461                                         "         [--use-syslog]\n"
 462                                         "         [--debug-<type> <level>]\n"
 463                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
 464                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 465                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 466                                         "\n"
 467                    );
 468         exit(msg == NULL? 0 : 1);
 469 }
 470
 471 /**
 472  * Main function, manages the daemon.
 473  */
 474 int main(int argc, char *argv[])
 475 {
 476         u_int crl_check_interval = 0;
 477         bool cache_crls = FALSE;
 478         bool use_syslog = FALSE;
 479
 480         private_daemon_t *private_charon;
 481         FILE *pid_file;
 482         struct stat stb;
 483         level_t levels[DBG_MAX];
 484         int signal;
 485
 486         /* silence the library during initialization, as we have no bus yet */
 487         dbg = dbg_silent;
 488
 489         /* initialize library */
 490         library_init(STRONGSWAN_CONF);
 491         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR, "libstrongswan-");
 492         lib->printf_hook->add_handler(lib->printf_hook, 'R',
 493                                                                   traffic_selector_get_printf_hooks());
 494         private_charon = daemon_create();
 495         charon = (daemon_t*)private_charon;
 496
 497         /* drop the capabilities we won't need for initialization */
 498         prctl(PR_SET_KEEPCAPS, 1);
 499         drop_capabilities(private_charon, FALSE);
 500
 501         /* use CTRL loglevel for default */
 502         for (signal = 0; signal < DBG_MAX; signal++)
 503         {
 504                 levels[signal] = LEVEL_CTRL;
 505         }
 506
 507         /* handle arguments */
 508         for (;;)
 509         {
 510                 struct option long_opts[] = {
 511                         { "help", no_argument, NULL, 'h' },
 512                         { "version", no_argument, NULL, 'v' },
 513                         { "use-syslog", no_argument, NULL, 'l' },
 514                         { "cachecrls", no_argument, NULL, 'C' },
 515                         { "crlcheckinterval", required_argument, NULL, 'x' },
 516                         /* TODO: handle "debug-all" */
 517                         { "debug-dmn", required_argument, &signal, DBG_DMN },
 518                         { "debug-mgr", required_argument, &signal, DBG_MGR },
 519                         { "debug-ike", required_argument, &signal, DBG_IKE },
 520                         { "debug-chd", required_argument, &signal, DBG_CHD },
 521                         { "debug-job", required_argument, &signal, DBG_JOB },
 522                         { "debug-cfg", required_argument, &signal, DBG_CFG },
 523                         { "debug-knl", required_argument, &signal, DBG_KNL },
 524                         { "debug-net", required_argument, &signal, DBG_NET },
 525                         { "debug-enc", required_argument, &signal, DBG_ENC },
 526                         { "debug-lib", required_argument, &signal, DBG_LIB },
 527                         { 0,0,0,0 }
 528                 };
 529
 530                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 531                 switch (c)
 532                 {
 533                         case EOF:
 534                         break;
 535                         case 'h':
 536                                 usage(NULL);
 537                                 break;
 538                         case 'v':
 539                                 printf("Linux strongSwan %s\n", VERSION);
 540                                 exit(0);
 541                         case 'l':
 542                                 use_syslog = TRUE;
 543                                 continue;
 544                         case 'C':
 545                                 cache_crls = TRUE;
 546                                 continue;
 547                         case 'x':
 548                                 crl_check_interval = atoi(optarg);
 549                                 continue;
 550                         case 0:
 551                                 /* option is in signal */
 552                                 levels[signal] = atoi(optarg);
 553                                 continue;
 554                         default:
 555                                 usage("");
 556                                 break;
 557                 }
 558                 break;
 559         }
 560
 561         /* initialize daemon */
 562         if (!initialize(private_charon, use_syslog, levels))
 563         {
 564                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 565                 destroy(private_charon);
 566                 exit(-1);
 567         }
 568
 569         /* check/setup PID file */
 570         if (stat(PID_FILE, &stb) == 0)
 571         {
 572                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 573                 destroy(private_charon);
 574                 exit(-1);
 575         }
 576         pid_file = fopen(PID_FILE, "w");
 577         if (pid_file)
 578         {
 579                 fprintf(pid_file, "%d\n", getpid());
 580                 fchown(fileno(pid_file), IPSEC_UID, IPSEC_GID);
 581                 fclose(pid_file);
 582         }
 583
 584         /* drop additional capabilites (bind & root) */
 585         drop_capabilities(private_charon, TRUE);
 586
 587         /* start the engine, go multithreaded */
 588         charon->processor->set_threads(charon->processor,
 589                                                 lib->settings->get_int(lib->settings, "charon.threads",
 590                                                                                            DEFAULT_THREADS));
 591
 592         /* run daemon */
 593         run(private_charon);
 594
 595         /* normal termination, cleanup and exit */
 596         destroy(private_charon);
 597         unlink(PID_FILE);
 598
 599         library_deinit();
 600
 601         return 0;
 602 }
 603