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 #ifdef HAVE_DLADDR
  20 # define _GNU_SOURCE
  21 # include <dlfcn.h>
  22 #endif /* HAVE_DLADDR */
  23
  24 #include <stdio.h>
  25 #include <sys/prctl.h>
  26 #include <signal.h>
  27 #include <pthread.h>
  28 #include <sys/stat.h>
  29 #include <sys/types.h>
  30 #include <unistd.h>
  31 #include <time.h>
  32 #include <string.h>
  33 #include <getopt.h>
  34 #include <errno.h>
  35 #include <pwd.h>
  36 #include <grp.h>
  37 #ifdef HAVE_BACKTRACE
  38 # include <execinfo.h>
  39 #endif /* HAVE_BACKTRACE */
  40 #ifdef CAPABILITIES
  41 #include <sys/capability.h>
  42 #endif /* CAPABILITIES */
  43
  44 #include "daemon.h"
  45
  46 #include <library.h>
  47 #include <config/traffic_selector.h>
  48 #include <config/proposal.h>
  49
  50 #ifdef INTEGRITY_TEST
  51 #include <fips/fips.h>
  52 #include <fips/fips_signature.h>
  53 #endif /* INTEGRITY_TEST */
  54
  55 typedef struct private_daemon_t private_daemon_t;
  56
  57 /**
  58  * Private additions to daemon_t, contains threads and internal functions.
  59  */
  60 struct private_daemon_t {
  61         /**
  62          * Public members of daemon_t.
  63          */
  64         daemon_t public;
  65
  66         /**
  67          * Signal set used for signal handling.
  68          */
  69         sigset_t signal_set;
  70
  71         /**
  72          * The thread_id of main-thread.
  73          */
  74         pthread_t main_thread_id;
  75
  76 #ifdef CAPABILITIES
  77         /**
  78          * capabilities to keep
  79          */
  80         cap_t caps;
  81 #endif /* CAPABILITIES */
  82 };
  83
  84 /**
  85  * One and only instance of the daemon.
  86  */
  87 daemon_t *charon;
  88
  89 /**
  90  * hook in library for debugging messages
  91  */
  92 extern void (*dbg) (int level, char *fmt, ...);
  93
  94 /**
  95  * Logging hook for library logs, spreads debug message over bus
  96  */
  97 static void dbg_bus(int level, char *fmt, ...)
  98 {
  99         va_list args;
 100
 101         va_start(args, fmt);
 102         charon->bus->vsignal(charon->bus, DBG_LIB, level, NULL, fmt, args);
 103         va_end(args);
 104 }
 105
 106 /**
 107  * Logging hook for library logs, using stderr output
 108  */
 109 static void dbg_stderr(int level, char *fmt, ...)
 110 {
 111         va_list args;
 112
 113         if (level <= 1)
 114         {
 115                 va_start(args, fmt);
 116                 fprintf(stderr, "00[LIB] ");
 117                 vfprintf(stderr, fmt, args);
 118                 fprintf(stderr, "\n");
 119                 va_end(args);
 120         }
 121 }
 122
 123 /**
 124  * Run the daemon and handle unix signals
 125  */
 126 static void run(private_daemon_t *this)
 127 {
 128         sigset_t set;
 129
 130         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
 131         sigemptyset(&set);
 132         sigaddset(&set, SIGINT);
 133         sigaddset(&set, SIGHUP);
 134         sigaddset(&set, SIGTERM);
 135
 136         while (TRUE)
 137         {
 138                 int sig;
 139                 int error;
 140
 141                 error = sigwait(&set, &sig);
 142                 if (error)
 143                 {
 144                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 145                         return;
 146                 }
 147                 switch (sig)
 148                 {
 149                         case SIGHUP:
 150                         {
 151                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
 152                                 break;
 153                         }
 154                         case SIGINT:
 155                         {
 156                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 157                                 return;
 158                         }
 159                         case SIGTERM:
 160                         {
 161                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 162                                 return;
 163                         }
 164                         default:
 165                         {
 166                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 167                                 break;
 168                         }
 169                 }
 170         }
 171 }
 172
 173 /**
 174  * Clean up all daemon resources
 175  */
 176 static void destroy(private_daemon_t *this)
 177 {
 178         /* terminate all idle threads */
 179         if (this->public.processor)
 180         {
 181                 this->public.processor->set_threads(this->public.processor, 0);
 182         }
 183         /* close all IKE_SAs */
 184         if (this->public.ike_sa_manager)
 185         {
 186                 this->public.ike_sa_manager->flush(this->public.ike_sa_manager);
 187         }
 188         /* unload plugins to release threads */
 189         lib->plugins->unload(lib->plugins);
 190 #ifdef CAPABILITIES
 191         cap_free(this->caps);
 192 #endif /* CAPABILITIES */
 193         DESTROY_IF(this->public.ike_sa_manager);
 194         DESTROY_IF(this->public.kernel_interface);
 195         DESTROY_IF(this->public.scheduler);
 196         DESTROY_IF(this->public.controller);
 197         DESTROY_IF(this->public.eap);
 198 #ifdef ME
 199         DESTROY_IF(this->public.connect_manager);
 200         DESTROY_IF(this->public.mediation_manager);
 201 #endif /* ME */
 202         DESTROY_IF(this->public.backends);
 203         DESTROY_IF(this->public.attributes);
 204         DESTROY_IF(this->public.credentials);
 205         DESTROY_IF(this->public.sender);
 206         DESTROY_IF(this->public.receiver);
 207         DESTROY_IF(this->public.socket);
 208         /* wait until all threads are gone */
 209         DESTROY_IF(this->public.processor);
 210
 211         /* rehook library logging, shutdown logging */
 212         dbg = dbg_stderr;
 213         DESTROY_IF(this->public.bus);
 214         DESTROY_IF(this->public.outlog);
 215         DESTROY_IF(this->public.syslog);
 216         DESTROY_IF(this->public.authlog);
 217         free(this);
 218 }
 219
 220 /**
 221  * Enforce daemon shutdown, with a given reason to do so.
 222  */
 223 static void kill_daemon(private_daemon_t *this, char *reason)
 224 {
 225         /* we send SIGTERM, so the daemon can cleanly shut down */
 226         if (this->public.bus)
 227         {
 228                 DBG1(DBG_DMN, "killing daemon: %s", reason);
 229         }
 230         else
 231         {
 232                 fprintf(stderr, "killing daemon: %s\n", reason);
 233         }
 234         if (this->main_thread_id == pthread_self())
 235         {
 236                 /* initialization failed, terminate daemon */
 237                 unlink(PID_FILE);
 238                 exit(-1);
 239         }
 240         else
 241         {
 242                 DBG1(DBG_DMN, "sending SIGTERM to ourself");
 243                 raise(SIGTERM);
 244                 /* thread must die, since he produced a ciritcal failure and can't continue */
 245                 pthread_exit(NULL);
 246         }
 247 }
 248
 249 /**
 250  * drop daemon capabilities
 251  */
 252 static void drop_capabilities(private_daemon_t *this)
 253 {
 254         prctl(PR_SET_KEEPCAPS, 1);
 255
 256         if (setgid(charon->gid) != 0)
 257         {
 258                 kill_daemon(this, "change to unprivileged group failed");
 259         }
 260         if (setuid(charon->uid) != 0)
 261         {
 262                 kill_daemon(this, "change to unprivileged user failed");
 263         }
 264
 265 #ifdef CAPABILITIES
 266         if (cap_set_proc(this->caps) != 0)
 267         {
 268                 kill_daemon(this, "unable to drop daemon capabilities");
 269         }
 270 #endif /* CAPABILITIES */
 271 }
 272
 273 /**
 274  * Implementation of daemon_t.keep_cap
 275  */
 276 static void keep_cap(private_daemon_t *this, u_int cap)
 277 {
 278 #ifdef CAPABILITIES
 279         cap_set_flag(this->caps, CAP_EFFECTIVE, 1, &cap, CAP_SET);
 280         cap_set_flag(this->caps, CAP_INHERITABLE, 1, &cap, CAP_SET);
 281         cap_set_flag(this->caps, CAP_PERMITTED, 1, &cap, CAP_SET);
 282 #endif /* CAPABILITIES */
 283 }
 284
 285 /**
 286  * lookup UID and GID
 287  */
 288 static void lookup_uid_gid(private_daemon_t *this)
 289 {
 290 #ifdef IPSEC_USER
 291         {
 292                 char buf[1024];
 293                 struct passwd passwd, *pwp;
 294
 295                 if (getpwnam_r(IPSEC_USER, &passwd, buf, sizeof(buf), &pwp) != 0 ||
 296                         pwp == NULL)
 297                 {
 298                         kill_daemon(this, "resolving user '"IPSEC_USER"' failed");
 299                 }
 300                 charon->uid = pwp->pw_uid;
 301         }
 302 #endif
 303 #ifdef IPSEC_GROUP
 304         {
 305                 char buf[1024];
 306                 struct group group, *grp;
 307
 308                 if (getgrnam_r(IPSEC_GROUP, &group, buf, sizeof(buf), &grp) != 0 ||
 309                         grp == NULL)
 310                 {
 311                         kill_daemon(this, "reslvoing group '"IPSEC_GROUP"' failed");
 312                 }
 313                 charon->gid = grp->gr_gid;
 314         }
 315 #endif
 316 }
 317
 318 /**
 319  * Initialize the daemon
 320  */
 321 static bool initialize(private_daemon_t *this, bool syslog, level_t levels[])
 322 {
 323         signal_t signal;
 324
 325         /* for uncritical pseudo random numbers */
 326         srandom(time(NULL) + getpid());
 327
 328         /* setup bus and it's listeners first to enable log output */
 329         this->public.bus = bus_create();
 330         this->public.outlog = file_logger_create(stdout);
 331         this->public.syslog = sys_logger_create(LOG_DAEMON);
 332         this->public.authlog = sys_logger_create(LOG_AUTHPRIV);
 333         this->public.bus->add_listener(this->public.bus, &this->public.syslog->listener);
 334         this->public.bus->add_listener(this->public.bus, &this->public.outlog->listener);
 335         this->public.bus->add_listener(this->public.bus, &this->public.authlog->listener);
 336         this->public.authlog->set_level(this->public.authlog, SIG_ANY, LEVEL_AUDIT);
 337         /* set up hook to log dbg message in library via charons message bus */
 338         dbg = dbg_bus;
 339
 340         /* apply loglevels */
 341         for (signal = 0; signal < DBG_MAX; signal++)
 342         {
 343                 this->public.syslog->set_level(this->public.syslog,
 344                                                                            signal, levels[signal]);
 345                 if (!syslog)
 346                 {
 347                         this->public.outlog->set_level(this->public.outlog,
 348                                                                                    signal, levels[signal]);
 349                 }
 350         }
 351
 352         DBG1(DBG_DMN, "starting charon (strongSwan Version %s)", VERSION);
 353
 354         /* load secrets, ca certificates and crls */
 355         this->public.processor = processor_create();
 356         this->public.scheduler = scheduler_create();
 357         this->public.credentials = credential_manager_create();
 358         this->public.controller = controller_create();
 359         this->public.eap = eap_manager_create();
 360         this->public.backends = backend_manager_create();
 361         this->public.attributes = attribute_manager_create();
 362         this->public.kernel_interface = kernel_interface_create();
 363         this->public.socket = socket_create();
 364
 365         /* load plugins, further infrastructure may need it */
 366         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR,
 367                 lib->settings->get_str(lib->settings, "charon.load", PLUGINS));
 368
 369         /* create the kernel interfaces */
 370         this->public.kernel_interface->create_interfaces(this->public.kernel_interface);
 371
 372 #ifdef INTEGRITY_TEST
 373         DBG1(DBG_DMN, "integrity test of libstrongswan code");
 374         if (fips_verify_hmac_signature(hmac_key, hmac_signature))
 375         {
 376                 DBG1(DBG_DMN, "  integrity test passed");
 377         }
 378         else
 379         {
 380                 DBG1(DBG_DMN, "  integrity test failed");
 381                 return FALSE;
 382         }
 383 #endif /* INTEGRITY_TEST */
 384
 385         this->public.ike_sa_manager = ike_sa_manager_create();
 386         if (this->public.ike_sa_manager == NULL)
 387         {
 388                 return FALSE;
 389         }
 390         this->public.sender = sender_create();
 391         this->public.receiver = receiver_create();
 392         if (this->public.receiver == NULL)
 393         {
 394                 return FALSE;
 395         }
 396
 397 #ifdef ME
 398         this->public.connect_manager = connect_manager_create();
 399         if (this->public.connect_manager == NULL)
 400         {
 401                 return FALSE;
 402         }
 403         this->public.mediation_manager = mediation_manager_create();
 404 #endif /* ME */
 405
 406         return TRUE;
 407 }
 408
 409 /**
 410  * Handle SIGSEGV/SIGILL signals raised by threads
 411  */
 412 static void segv_handler(int signal)
 413 {
 414 #ifdef HAVE_BACKTRACE
 415         void *array[20];
 416         size_t size;
 417         char **strings;
 418         size_t i;
 419
 420         size = backtrace(array, 20);
 421         strings = backtrace_symbols(array, size);
 422
 423         DBG1(DBG_JOB, "thread %u received %s. Dumping %d frames from stack:",
 424                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL", size);
 425
 426         for (i = 0; i < size; i++)
 427         {
 428 #ifdef HAVE_DLADDR
 429                 Dl_info info;
 430
 431                 if (dladdr(array[i], &info))
 432                 {
 433                         void *ptr = array[i];
 434                         if (strstr(info.dli_fname, ".so"))
 435                         {
 436                                 ptr = (void*)(array[i] - info.dli_fbase);
 437                         }
 438                         DBG1(DBG_DMN, "    %s [%p]", info.dli_fname, ptr);
 439                 }
 440                 else
 441                 {
 442 #endif /* HAVE_DLADDR */
 443                         DBG1(DBG_DMN, "    %s", strings[i]);
 444 #ifdef HAVE_DLADDR
 445                 }
 446 #endif /* HAVE_DLADDR */
 447         }
 448         free (strings);
 449 #else /* !HAVE_BACKTRACE */
 450         DBG1(DBG_DMN, "thread %u received %s",
 451                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
 452 #endif /* HAVE_BACKTRACE */
 453         DBG1(DBG_DMN, "killing ourself, received critical signal");
 454         raise(SIGKILL);
 455 }
 456
 457 /**
 458  * Create the daemon.
 459  */
 460 private_daemon_t *daemon_create(void)
 461 {
 462         struct sigaction action;
 463         private_daemon_t *this = malloc_thing(private_daemon_t);
 464
 465         /* assign methods */
 466         this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
 467         this->public.keep_cap = (void(*)(daemon_t*, u_int cap))keep_cap;
 468
 469         /* NULL members for clean destruction */
 470         this->public.socket = NULL;
 471         this->public.ike_sa_manager = NULL;
 472         this->public.credentials = NULL;
 473         this->public.backends = NULL;
 474         this->public.attributes = NULL;
 475         this->public.sender= NULL;
 476         this->public.receiver = NULL;
 477         this->public.scheduler = NULL;
 478         this->public.kernel_interface = NULL;
 479         this->public.processor = NULL;
 480         this->public.controller = NULL;
 481         this->public.eap = NULL;
 482         this->public.bus = NULL;
 483         this->public.outlog = NULL;
 484         this->public.syslog = NULL;
 485         this->public.authlog = NULL;
 486 #ifdef ME
 487         this->public.connect_manager = NULL;
 488         this->public.mediation_manager = NULL;
 489 #endif /* ME */
 490         this->public.uid = 0;
 491         this->public.gid = 0;
 492
 493         this->main_thread_id = pthread_self();
 494 #ifdef CAPABILITIES
 495         this->caps = cap_init();
 496         keep_cap(this, CAP_NET_ADMIN);
 497         if (lib->leak_detective)
 498         {
 499                 keep_cap(this, CAP_SYS_NICE);
 500         }
 501 #endif /* CAPABILITIES */
 502
 503         /* add handler for SEGV and ILL,
 504          * add handler for USR1 (cancellation).
 505          * INT, TERM and HUP are handled by sigwait() in run() */
 506         action.sa_handler = segv_handler;
 507         action.sa_flags = 0;
 508         sigemptyset(&action.sa_mask);
 509         sigaddset(&action.sa_mask, SIGINT);
 510         sigaddset(&action.sa_mask, SIGTERM);
 511         sigaddset(&action.sa_mask, SIGHUP);
 512         sigaction(SIGSEGV, &action, NULL);
 513         sigaction(SIGILL, &action, NULL);
 514         action.sa_handler = SIG_IGN;
 515         sigaction(SIGPIPE, &action, NULL);
 516
 517         pthread_sigmask(SIG_SETMASK, &action.sa_mask, 0);
 518
 519         return this;
 520 }
 521
 522 /**
 523  * print command line usage and exit
 524  */
 525 static void usage(const char *msg)
 526 {
 527         if (msg != NULL && *msg != '\0')
 528         {
 529                 fprintf(stderr, "%s\n", msg);
 530         }
 531         fprintf(stderr, "Usage: charon\n"
 532                                         "         [--help]\n"
 533                                         "         [--version]\n"
 534                                         "         [--use-syslog]\n"
 535                                         "         [--debug-<type> <level>]\n"
 536                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
 537                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 538                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 539                                         "\n"
 540                    );
 541         exit(msg == NULL? 0 : 1);
 542 }
 543
 544 /**
 545  * Main function, manages the daemon.
 546  */
 547 int main(int argc, char *argv[])
 548 {
 549         bool use_syslog = FALSE;
 550
 551         private_daemon_t *private_charon;
 552         FILE *pid_file;
 553         struct stat stb;
 554         level_t levels[DBG_MAX];
 555         int signal;
 556
 557         /* logging for library during initialization, as we have no bus yet */
 558         dbg = dbg_stderr;
 559
 560         /* initialize library */
 561         library_init(STRONGSWAN_CONF);
 562         lib->printf_hook->add_handler(lib->printf_hook, 'R',
 563                                                                   traffic_selector_get_printf_hooks());
 564         lib->printf_hook->add_handler(lib->printf_hook, 'P',
 565                                                                   proposal_get_printf_hooks());
 566         private_charon = daemon_create();
 567         charon = (daemon_t*)private_charon;
 568
 569         lookup_uid_gid(private_charon);
 570
 571         /* use CTRL loglevel for default */
 572         for (signal = 0; signal < DBG_MAX; signal++)
 573         {
 574                 levels[signal] = LEVEL_CTRL;
 575         }
 576
 577         /* handle arguments */
 578         for (;;)
 579         {
 580                 struct option long_opts[] = {
 581                         { "help", no_argument, NULL, 'h' },
 582                         { "version", no_argument, NULL, 'v' },
 583                         { "use-syslog", no_argument, NULL, 'l' },
 584                         /* TODO: handle "debug-all" */
 585                         { "debug-dmn", required_argument, &signal, DBG_DMN },
 586                         { "debug-mgr", required_argument, &signal, DBG_MGR },
 587                         { "debug-ike", required_argument, &signal, DBG_IKE },
 588                         { "debug-chd", required_argument, &signal, DBG_CHD },
 589                         { "debug-job", required_argument, &signal, DBG_JOB },
 590                         { "debug-cfg", required_argument, &signal, DBG_CFG },
 591                         { "debug-knl", required_argument, &signal, DBG_KNL },
 592                         { "debug-net", required_argument, &signal, DBG_NET },
 593                         { "debug-enc", required_argument, &signal, DBG_ENC },
 594                         { "debug-lib", required_argument, &signal, DBG_LIB },
 595                         { 0,0,0,0 }
 596                 };
 597
 598                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 599                 switch (c)
 600                 {
 601                         case EOF:
 602                         break;
 603                         case 'h':
 604                                 usage(NULL);
 605                                 break;
 606                         case 'v':
 607                                 printf("Linux strongSwan %s\n", VERSION);
 608                                 exit(0);
 609                         case 'l':
 610                                 use_syslog = TRUE;
 611                                 continue;
 612                         case 0:
 613                                 /* option is in signal */
 614                                 levels[signal] = atoi(optarg);
 615                                 continue;
 616                         default:
 617                                 usage("");
 618                                 break;
 619                 }
 620                 break;
 621         }
 622
 623         /* initialize daemon */
 624         if (!initialize(private_charon, use_syslog, levels))
 625         {
 626                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 627                 destroy(private_charon);
 628                 exit(-1);
 629         }
 630
 631         /* check/setup PID file */
 632         if (stat(PID_FILE, &stb) == 0)
 633         {
 634                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 635                 destroy(private_charon);
 636                 exit(-1);
 637         }
 638         pid_file = fopen(PID_FILE, "w");
 639         if (pid_file)
 640         {
 641                 fprintf(pid_file, "%d\n", getpid());
 642                 fchown(fileno(pid_file), charon->uid, charon->gid);
 643                 fclose(pid_file);
 644         }
 645
 646         /* drop the capabilities we won't need */
 647         drop_capabilities(private_charon);
 648
 649         /* start the engine, go multithreaded */
 650         charon->processor->set_threads(charon->processor,
 651                                                 lib->settings->get_int(lib->settings, "charon.threads",
 652                                                                                            DEFAULT_THREADS));
 653
 654         /* run daemon */
 655         run(private_charon);
 656
 657         /* normal termination, cleanup and exit */
 658         destroy(private_charon);
 659         unlink(PID_FILE);
 660
 661         library_deinit();
 662
 663         return 0;
 664 }
 665