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