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 /**
  95  * Logging hook for library logs, using stderr output
  96  */
  97 static void dbg_stderr(int level, char *fmt, ...)
  98 {
  99         va_list args;
 100
 101         if (level <= 1)
 102         {
 103                 va_start(args, fmt);
 104                 fprintf(stderr, "00[LIB] ");
 105                 vfprintf(stderr, fmt, args);
 106                 fprintf(stderr, "\n");
 107                 va_end(args);
 108         }
 109 }
 110
 111 /**
 112  * Run the daemon and handle unix signals
 113  */
 114 static void run(private_daemon_t *this)
 115 {
 116         sigset_t set;
 117
 118         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
 119         sigemptyset(&set);
 120         sigaddset(&set, SIGINT);
 121         sigaddset(&set, SIGHUP);
 122         sigaddset(&set, SIGTERM);
 123
 124         while (TRUE)
 125         {
 126                 int sig;
 127                 int error;
 128
 129                 error = sigwait(&set, &sig);
 130                 if (error)
 131                 {
 132                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 133                         return;
 134                 }
 135                 switch (sig)
 136                 {
 137                         case SIGHUP:
 138                         {
 139                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
 140                                 break;
 141                         }
 142                         case SIGINT:
 143                         {
 144                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 145                                 return;
 146                         }
 147                         case SIGTERM:
 148                         {
 149                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 150                                 return;
 151                         }
 152                         default:
 153                         {
 154                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 155                                 break;
 156                         }
 157                 }
 158         }
 159 }
 160
 161 /**
 162  * Clean up all daemon resources
 163  */
 164 static void destroy(private_daemon_t *this)
 165 {
 166         /* terminate all idle threads */
 167         if (this->public.processor)
 168         {
 169                 this->public.processor->set_threads(this->public.processor, 0);
 170         }
 171         /* close all IKE_SAs */
 172         if (this->public.ike_sa_manager)
 173         {
 174                 this->public.ike_sa_manager->flush(this->public.ike_sa_manager);
 175         }
 176         DESTROY_IF(this->public.plugins);
 177         DESTROY_IF(this->public.ike_sa_manager);
 178         DESTROY_IF(this->public.kernel_interface);
 179         DESTROY_IF(this->public.scheduler);
 180         DESTROY_IF(this->public.controller);
 181         DESTROY_IF(this->public.eap);
 182 #ifdef ME
 183         DESTROY_IF(this->public.connect_manager);
 184         DESTROY_IF(this->public.mediation_manager);
 185 #endif /* ME */
 186         DESTROY_IF(this->public.backends);
 187         DESTROY_IF(this->public.attributes);
 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) | (1<<CAP_SYS_NICE);
 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.attributes = attribute_manager_create();
 342         this->public.plugins = plugin_loader_create();
 343         this->public.kernel_interface = kernel_interface_create();
 344         this->public.socket = socket_create();
 345         this->public.sender = sender_create();
 346         this->public.receiver = receiver_create();
 347         if (this->public.receiver == NULL)
 348         {
 349                 return FALSE;
 350         }
 351
 352 #ifdef ME
 353         this->public.connect_manager = connect_manager_create();
 354         if (this->public.connect_manager == NULL)
 355         {
 356                 return FALSE;
 357         }
 358         this->public.mediation_manager = mediation_manager_create();
 359 #endif /* ME */
 360
 361         this->public.plugins->load(this->public.plugins, IPSEC_PLUGINDIR, "libcharon-");
 362
 363         return TRUE;
 364 }
 365
 366 /**
 367  * Handle SIGSEGV/SIGILL signals raised by threads
 368  */
 369 static void segv_handler(int signal)
 370 {
 371 #ifdef HAVE_BACKTRACE
 372         void *array[20];
 373         size_t size;
 374         char **strings;
 375         size_t i;
 376
 377         size = backtrace(array, 20);
 378         strings = backtrace_symbols(array, size);
 379
 380         DBG1(DBG_JOB, "thread %u received %s. Dumping %d frames from stack:",
 381                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL", size);
 382
 383         for (i = 0; i < size; i++)
 384         {
 385                 DBG1(DBG_DMN, "    %s", strings[i]);
 386         }
 387         free (strings);
 388 #else /* !HAVE_BACKTRACE */
 389         DBG1(DBG_DMN, "thread %u received %s",
 390                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
 391 #endif /* HAVE_BACKTRACE */
 392         DBG1(DBG_DMN, "killing ourself, received critical signal");
 393         raise(SIGKILL);
 394 }
 395
 396 /**
 397  * Create the daemon.
 398  */
 399 private_daemon_t *daemon_create(void)
 400 {
 401         struct sigaction action;
 402         private_daemon_t *this = malloc_thing(private_daemon_t);
 403
 404         /* assign methods */
 405         this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
 406
 407         /* NULL members for clean destruction */
 408         this->public.socket = NULL;
 409         this->public.ike_sa_manager = NULL;
 410         this->public.credentials = NULL;
 411         this->public.backends = NULL;
 412         this->public.attributes = NULL;
 413         this->public.sender= NULL;
 414         this->public.receiver = NULL;
 415         this->public.scheduler = NULL;
 416         this->public.kernel_interface = NULL;
 417         this->public.processor = NULL;
 418         this->public.controller = NULL;
 419         this->public.eap = NULL;
 420         this->public.plugins = NULL;
 421         this->public.bus = NULL;
 422         this->public.outlog = NULL;
 423         this->public.syslog = NULL;
 424         this->public.authlog = NULL;
 425
 426         this->main_thread_id = pthread_self();
 427
 428         /* add handler for SEGV and ILL,
 429          * add handler for USR1 (cancellation).
 430          * INT, TERM and HUP are handled by sigwait() in run() */
 431         action.sa_handler = segv_handler;
 432         action.sa_flags = 0;
 433         sigemptyset(&action.sa_mask);
 434         sigaddset(&action.sa_mask, SIGINT);
 435         sigaddset(&action.sa_mask, SIGTERM);
 436         sigaddset(&action.sa_mask, SIGHUP);
 437         sigaction(SIGSEGV, &action, NULL);
 438         sigaction(SIGILL, &action, NULL);
 439         action.sa_handler = SIG_IGN;
 440         sigaction(SIGPIPE, &action, NULL);
 441
 442         pthread_sigmask(SIG_SETMASK, &action.sa_mask, 0);
 443
 444         return this;
 445 }
 446
 447 /**
 448  * print command line usage and exit
 449  */
 450 static void usage(const char *msg)
 451 {
 452         if (msg != NULL && *msg != '\0')
 453         {
 454                 fprintf(stderr, "%s\n", msg);
 455         }
 456         fprintf(stderr, "Usage: charon\n"
 457                                         "         [--help]\n"
 458                                         "         [--version]\n"
 459                                         "         [--use-syslog]\n"
 460                                         "         [--debug-<type> <level>]\n"
 461                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
 462                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 463                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 464                                         "\n"
 465                    );
 466         exit(msg == NULL? 0 : 1);
 467 }
 468
 469 /**
 470  * Main function, manages the daemon.
 471  */
 472 int main(int argc, char *argv[])
 473 {
 474         bool use_syslog = FALSE;
 475
 476         private_daemon_t *private_charon;
 477         FILE *pid_file;
 478         struct stat stb;
 479         level_t levels[DBG_MAX];
 480         int signal;
 481
 482         /* logging for library during initialization, as we have no bus yet */
 483         dbg = dbg_stderr;
 484
 485         /* initialize library */
 486         library_init(STRONGSWAN_CONF);
 487         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR, "libstrongswan-");
 488         lib->printf_hook->add_handler(lib->printf_hook, 'R',
 489                                                                   traffic_selector_get_printf_hooks());
 490         private_charon = daemon_create();
 491         charon = (daemon_t*)private_charon;
 492
 493         /* drop the capabilities we won't need for initialization */
 494         prctl(PR_SET_KEEPCAPS, 1);
 495         drop_capabilities(private_charon, FALSE);
 496
 497         /* use CTRL loglevel for default */
 498         for (signal = 0; signal < DBG_MAX; signal++)
 499         {
 500                 levels[signal] = LEVEL_CTRL;
 501         }
 502
 503         /* handle arguments */
 504         for (;;)
 505         {
 506                 struct option long_opts[] = {
 507                         { "help", no_argument, NULL, 'h' },
 508                         { "version", no_argument, NULL, 'v' },
 509                         { "use-syslog", no_argument, NULL, 'l' },
 510                         /* TODO: handle "debug-all" */
 511                         { "debug-dmn", required_argument, &signal, DBG_DMN },
 512                         { "debug-mgr", required_argument, &signal, DBG_MGR },
 513                         { "debug-ike", required_argument, &signal, DBG_IKE },
 514                         { "debug-chd", required_argument, &signal, DBG_CHD },
 515                         { "debug-job", required_argument, &signal, DBG_JOB },
 516                         { "debug-cfg", required_argument, &signal, DBG_CFG },
 517                         { "debug-knl", required_argument, &signal, DBG_KNL },
 518                         { "debug-net", required_argument, &signal, DBG_NET },
 519                         { "debug-enc", required_argument, &signal, DBG_ENC },
 520                         { "debug-lib", required_argument, &signal, DBG_LIB },
 521                         { 0,0,0,0 }
 522                 };
 523
 524                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 525                 switch (c)
 526                 {
 527                         case EOF:
 528                         break;
 529                         case 'h':
 530                                 usage(NULL);
 531                                 break;
 532                         case 'v':
 533                                 printf("Linux strongSwan %s\n", VERSION);
 534                                 exit(0);
 535                         case 'l':
 536                                 use_syslog = TRUE;
 537                                 continue;
 538                         case 0:
 539                                 /* option is in signal */
 540                                 levels[signal] = atoi(optarg);
 541                                 continue;
 542                         default:
 543                                 usage("");
 544                                 break;
 545                 }
 546                 break;
 547         }
 548
 549         /* initialize daemon */
 550         if (!initialize(private_charon, use_syslog, levels))
 551         {
 552                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 553                 destroy(private_charon);
 554                 exit(-1);
 555         }
 556
 557         /* check/setup PID file */
 558         if (stat(PID_FILE, &stb) == 0)
 559         {
 560                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 561                 destroy(private_charon);
 562                 exit(-1);
 563         }
 564         pid_file = fopen(PID_FILE, "w");
 565         if (pid_file)
 566         {
 567                 fprintf(pid_file, "%d\n", getpid());
 568                 fchown(fileno(pid_file), IPSEC_UID, IPSEC_GID);
 569                 fclose(pid_file);
 570         }
 571
 572         /* drop additional capabilites (bind & root) */
 573         drop_capabilities(private_charon, TRUE);
 574
 575         /* start the engine, go multithreaded */
 576         charon->processor->set_threads(charon->processor,
 577                                                 lib->settings->get_int(lib->settings, "charon.threads",
 578                                                                                            DEFAULT_THREADS));
 579
 580         /* run daemon */
 581         run(private_charon);
 582
 583         /* normal termination, cleanup and exit */
 584         destroy(private_charon);
 585         unlink(PID_FILE);
 586
 587         library_deinit();
 588
 589         return 0;
 590 }
 591