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 #include <pwd.h>
  32 #include <grp.h>
  33 #ifdef HAVE_BACKTRACE
  34 # include <execinfo.h>
  35 #endif /* HAVE_BACKTRACE */
  36
  37 #include "daemon.h"
  38
  39 #include <library.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 /**
  97  * Logging hook for library logs, using stderr output
  98  */
  99 static void dbg_stderr(int level, char *fmt, ...)
 100 {
 101         va_list args;
 102
 103         if (level <= 1)
 104         {
 105                 va_start(args, fmt);
 106                 fprintf(stderr, "00[LIB] ");
 107                 vfprintf(stderr, fmt, args);
 108                 fprintf(stderr, "\n");
 109                 va_end(args);
 110         }
 111 }
 112
 113 /**
 114  * Run the daemon and handle unix signals
 115  */
 116 static void run(private_daemon_t *this)
 117 {
 118         sigset_t set;
 119
 120         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
 121         sigemptyset(&set);
 122         sigaddset(&set, SIGINT);
 123         sigaddset(&set, SIGHUP);
 124         sigaddset(&set, SIGTERM);
 125
 126         while (TRUE)
 127         {
 128                 int sig;
 129                 int error;
 130
 131                 error = sigwait(&set, &sig);
 132                 if (error)
 133                 {
 134                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 135                         return;
 136                 }
 137                 switch (sig)
 138                 {
 139                         case SIGHUP:
 140                         {
 141                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
 142                                 break;
 143                         }
 144                         case SIGINT:
 145                         {
 146                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 147                                 return;
 148                         }
 149                         case SIGTERM:
 150                         {
 151                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 152                                 return;
 153                         }
 154                         default:
 155                         {
 156                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 157                                 break;
 158                         }
 159                 }
 160         }
 161 }
 162
 163 /**
 164  * Clean up all daemon resources
 165  */
 166 static void destroy(private_daemon_t *this)
 167 {
 168         /* terminate all idle threads */
 169         if (this->public.processor)
 170         {
 171                 this->public.processor->set_threads(this->public.processor, 0);
 172         }
 173         /* close all IKE_SAs */
 174         if (this->public.ike_sa_manager)
 175         {
 176                 this->public.ike_sa_manager->flush(this->public.ike_sa_manager);
 177         }
 178         DESTROY_IF(this->public.plugins);
 179         DESTROY_IF(this->public.ike_sa_manager);
 180         DESTROY_IF(this->public.kernel_interface);
 181         DESTROY_IF(this->public.scheduler);
 182         DESTROY_IF(this->public.controller);
 183         DESTROY_IF(this->public.eap);
 184 #ifdef ME
 185         DESTROY_IF(this->public.connect_manager);
 186         DESTROY_IF(this->public.mediation_manager);
 187 #endif /* ME */
 188         DESTROY_IF(this->public.backends);
 189         DESTROY_IF(this->public.attributes);
 190         DESTROY_IF(this->public.credentials);
 191         DESTROY_IF(this->public.sender);
 192         DESTROY_IF(this->public.receiver);
 193         DESTROY_IF(this->public.socket);
 194         /* wait until all threads are gone */
 195         DESTROY_IF(this->public.processor);
 196
 197         /* rehook library logging, shutdown logging */
 198         dbg = dbg_stderr;
 199         DESTROY_IF(this->public.bus);
 200         DESTROY_IF(this->public.outlog);
 201         DESTROY_IF(this->public.syslog);
 202         DESTROY_IF(this->public.authlog);
 203         free(this);
 204 }
 205
 206 /**
 207  * Enforce daemon shutdown, with a given reason to do so.
 208  */
 209 static void kill_daemon(private_daemon_t *this, char *reason)
 210 {
 211         /* we send SIGTERM, so the daemon can cleanly shut down */
 212         if (this->public.bus)
 213         {
 214                 DBG1(DBG_DMN, "killing daemon: %s", reason);
 215         }
 216         else
 217         {
 218                 fprintf(stderr, "killing daemon: %s\n", reason);
 219         }
 220         if (this->main_thread_id == pthread_self())
 221         {
 222                 /* initialization failed, terminate daemon */
 223                 unlink(PID_FILE);
 224                 exit(-1);
 225         }
 226         else
 227         {
 228                 DBG1(DBG_DMN, "sending SIGTERM to ourself");
 229                 raise(SIGTERM);
 230                 /* thread must die, since he produced a ciritcal failure and can't continue */
 231                 pthread_exit(NULL);
 232         }
 233 }
 234
 235 /**
 236  * drop daemon capabilities
 237  */
 238 static void drop_capabilities(private_daemon_t *this, bool full)
 239 {
 240         struct __user_cap_header_struct hdr;
 241         struct __user_cap_data_struct data;
 242
 243         /* CAP_NET_ADMIN is needed to use netlink */
 244         u_int32_t keep = (1<<CAP_NET_ADMIN) | (1<<CAP_SYS_NICE);
 245
 246         if (full)
 247         {
 248                 if (setgid(charon->gid) != 0)
 249                 {
 250                         kill_daemon(this, "change to unprivileged group failed");
 251                 }
 252                 if (setuid(charon->uid) != 0)
 253                 {
 254                         kill_daemon(this, "change to unprivileged user failed");
 255                 }
 256         }
 257         else
 258         {
 259                 /* CAP_NET_BIND_SERVICE to bind services below port 1024 */
 260                 keep |= (1<<CAP_NET_BIND_SERVICE);
 261                 /* CAP_NET_RAW to create RAW sockets */
 262                 keep |= (1<<CAP_NET_RAW);
 263                 /* CAP_DAC_READ_SEARCH to read ipsec.secrets */
 264                 keep |= (1<<CAP_DAC_READ_SEARCH);
 265                 /* CAP_CHOWN to change file permissions (socket permissions) */
 266                 keep |= (1<<CAP_CHOWN);
 267                 /* CAP_SETUID to call setuid()  */
 268                 keep |= (1<<CAP_SETUID);
 269                 /* CAP_SETGID to call setgid() */
 270                 keep |= (1<<CAP_SETGID);
 271         }
 272
 273         /* we use the old capset version for now. For systems with version 2
 274          * available, we specifiy version 1 excplicitly. */
 275 #ifdef _LINUX_CAPABILITY_VERSION_1
 276         hdr.version = _LINUX_CAPABILITY_VERSION_1;
 277 #else
 278         hdr.version = _LINUX_CAPABILITY_VERSION;
 279 #endif
 280         hdr.pid = 0;
 281         data.inheritable = data.effective = data.permitted = keep;
 282
 283         if (capset(&hdr, &data))
 284         {
 285                 kill_daemon(this, "unable to drop daemon capabilities");
 286         }
 287 }
 288
 289 /**
 290  * lookup UID and GID
 291  */
 292 static void lookup_uid_gid(private_daemon_t *this)
 293 {
 294 #ifdef IPSEC_USER
 295         {
 296                 char buf[1024];
 297                 struct passwd passwd, *pwp;
 298
 299                 if (getpwnam_r(IPSEC_USER, &passwd, buf, sizeof(buf), &pwp) != 0 ||
 300                         pwp == NULL)
 301                 {
 302                         kill_daemon(this, "resolving user '"IPSEC_USER"' failed");
 303                 }
 304                 charon->uid = pwp->pw_uid;
 305         }
 306 #endif
 307 #ifdef IPSEC_GROUP
 308         {
 309                 char buf[1024];
 310                 struct group group, *grp;
 311
 312                 if (getgrnam_r(IPSEC_GROUP, &group, buf, sizeof(buf), &grp) != 0 ||
 313                         grp == NULL)
 314                 {
 315                         kill_daemon(this, "reslvoing group '"IPSEC_GROUP"' failed");
 316                 }
 317                 charon->gid = grp->gr_gid;
 318         }
 319 #endif
 320 }
 321
 322 /**
 323  * Initialize the daemon
 324  */
 325 static bool initialize(private_daemon_t *this, bool syslog, level_t levels[])
 326 {
 327         signal_t signal;
 328
 329         /* for uncritical pseudo random numbers */
 330         srandom(time(NULL) + getpid());
 331
 332         /* setup bus and it's listeners first to enable log output */
 333         this->public.bus = bus_create();
 334         this->public.outlog = file_logger_create(stdout);
 335         this->public.syslog = sys_logger_create(LOG_DAEMON);
 336         this->public.authlog = sys_logger_create(LOG_AUTHPRIV);
 337         this->public.bus->add_listener(this->public.bus, &this->public.syslog->listener);
 338         this->public.bus->add_listener(this->public.bus, &this->public.outlog->listener);
 339         this->public.bus->add_listener(this->public.bus, &this->public.authlog->listener);
 340         this->public.authlog->set_level(this->public.authlog, SIG_ANY, LEVEL_AUDIT);
 341         /* set up hook to log dbg message in library via charons message bus */
 342         dbg = dbg_bus;
 343
 344         /* apply loglevels */
 345         for (signal = 0; signal < DBG_MAX; signal++)
 346         {
 347                 this->public.syslog->set_level(this->public.syslog,
 348                                                                            signal, levels[signal]);
 349                 if (!syslog)
 350                 {
 351                         this->public.outlog->set_level(this->public.outlog,
 352                                                                                    signal, levels[signal]);
 353                 }
 354         }
 355
 356         DBG1(DBG_DMN, "starting charon (strongSwan Version %s)", VERSION);
 357
 358 #ifdef INTEGRITY_TEST
 359         DBG1(DBG_DMN, "integrity test of libstrongswan code");
 360         if (fips_verify_hmac_signature(hmac_key, hmac_signature))
 361         {
 362                 DBG1(DBG_DMN, "  integrity test passed");
 363         }
 364         else
 365         {
 366                 DBG1(DBG_DMN, "  integrity test failed");
 367                 return FALSE;
 368         }
 369 #endif /* INTEGRITY_TEST */
 370
 371         this->public.ike_sa_manager = ike_sa_manager_create();
 372         if (this->public.ike_sa_manager == NULL)
 373         {
 374                 return FALSE;
 375         }
 376         this->public.processor = processor_create();
 377         this->public.scheduler = scheduler_create();
 378
 379         /* load secrets, ca certificates and crls */
 380         this->public.credentials = credential_manager_create();
 381         this->public.controller = controller_create();
 382         this->public.eap = eap_manager_create();
 383         this->public.backends = backend_manager_create();
 384         this->public.attributes = attribute_manager_create();
 385         this->public.plugins = plugin_loader_create();
 386         this->public.kernel_interface = kernel_interface_create();
 387         this->public.socket = socket_create();
 388         this->public.sender = sender_create();
 389         this->public.receiver = receiver_create();
 390         if (this->public.receiver == NULL)
 391         {
 392                 return FALSE;
 393         }
 394
 395 #ifdef ME
 396         this->public.connect_manager = connect_manager_create();
 397         if (this->public.connect_manager == NULL)
 398         {
 399                 return FALSE;
 400         }
 401         this->public.mediation_manager = mediation_manager_create();
 402 #endif /* ME */
 403
 404         this->public.plugins->load(this->public.plugins, IPSEC_PLUGINDIR, "libcharon-");
 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                 DBG1(DBG_DMN, "    %s", strings[i]);
 429         }
 430         free (strings);
 431 #else /* !HAVE_BACKTRACE */
 432         DBG1(DBG_DMN, "thread %u received %s",
 433                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
 434 #endif /* HAVE_BACKTRACE */
 435         DBG1(DBG_DMN, "killing ourself, received critical signal");
 436         raise(SIGKILL);
 437 }
 438
 439 /**
 440  * Create the daemon.
 441  */
 442 private_daemon_t *daemon_create(void)
 443 {
 444         struct sigaction action;
 445         private_daemon_t *this = malloc_thing(private_daemon_t);
 446
 447         /* assign methods */
 448         this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
 449
 450         /* NULL members for clean destruction */
 451         this->public.socket = NULL;
 452         this->public.ike_sa_manager = NULL;
 453         this->public.credentials = NULL;
 454         this->public.backends = NULL;
 455         this->public.attributes = NULL;
 456         this->public.sender= NULL;
 457         this->public.receiver = NULL;
 458         this->public.scheduler = NULL;
 459         this->public.kernel_interface = NULL;
 460         this->public.processor = NULL;
 461         this->public.controller = NULL;
 462         this->public.eap = NULL;
 463         this->public.plugins = NULL;
 464         this->public.bus = NULL;
 465         this->public.outlog = NULL;
 466         this->public.syslog = NULL;
 467         this->public.authlog = NULL;
 468         this->public.uid = 0;
 469         this->public.gid = 0;
 470
 471         this->main_thread_id = pthread_self();
 472
 473         /* add handler for SEGV and ILL,
 474          * add handler for USR1 (cancellation).
 475          * INT, TERM and HUP are handled by sigwait() in run() */
 476         action.sa_handler = segv_handler;
 477         action.sa_flags = 0;
 478         sigemptyset(&action.sa_mask);
 479         sigaddset(&action.sa_mask, SIGINT);
 480         sigaddset(&action.sa_mask, SIGTERM);
 481         sigaddset(&action.sa_mask, SIGHUP);
 482         sigaction(SIGSEGV, &action, NULL);
 483         sigaction(SIGILL, &action, NULL);
 484         action.sa_handler = SIG_IGN;
 485         sigaction(SIGPIPE, &action, NULL);
 486
 487         pthread_sigmask(SIG_SETMASK, &action.sa_mask, 0);
 488
 489         return this;
 490 }
 491
 492 /**
 493  * print command line usage and exit
 494  */
 495 static void usage(const char *msg)
 496 {
 497         if (msg != NULL && *msg != '\0')
 498         {
 499                 fprintf(stderr, "%s\n", msg);
 500         }
 501         fprintf(stderr, "Usage: charon\n"
 502                                         "         [--help]\n"
 503                                         "         [--version]\n"
 504                                         "         [--use-syslog]\n"
 505                                         "         [--debug-<type> <level>]\n"
 506                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
 507                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 508                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 509                                         "\n"
 510                    );
 511         exit(msg == NULL? 0 : 1);
 512 }
 513
 514 /**
 515  * Main function, manages the daemon.
 516  */
 517 int main(int argc, char *argv[])
 518 {
 519         bool use_syslog = FALSE;
 520
 521         private_daemon_t *private_charon;
 522         FILE *pid_file;
 523         struct stat stb;
 524         level_t levels[DBG_MAX];
 525         int signal;
 526
 527         /* logging for library during initialization, as we have no bus yet */
 528         dbg = dbg_stderr;
 529
 530         /* initialize library */
 531         library_init(STRONGSWAN_CONF);
 532         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR, "libstrongswan-");
 533         lib->printf_hook->add_handler(lib->printf_hook, 'R',
 534                                                                   traffic_selector_get_printf_hooks());
 535         private_charon = daemon_create();
 536         charon = (daemon_t*)private_charon;
 537
 538         lookup_uid_gid(private_charon);
 539
 540         /* drop the capabilities we won't need for initialization */
 541         prctl(PR_SET_KEEPCAPS, 1);
 542         drop_capabilities(private_charon, FALSE);
 543
 544         /* use CTRL loglevel for default */
 545         for (signal = 0; signal < DBG_MAX; signal++)
 546         {
 547                 levels[signal] = LEVEL_CTRL;
 548         }
 549
 550         /* handle arguments */
 551         for (;;)
 552         {
 553                 struct option long_opts[] = {
 554                         { "help", no_argument, NULL, 'h' },
 555                         { "version", no_argument, NULL, 'v' },
 556                         { "use-syslog", no_argument, NULL, 'l' },
 557                         /* TODO: handle "debug-all" */
 558                         { "debug-dmn", required_argument, &signal, DBG_DMN },
 559                         { "debug-mgr", required_argument, &signal, DBG_MGR },
 560                         { "debug-ike", required_argument, &signal, DBG_IKE },
 561                         { "debug-chd", required_argument, &signal, DBG_CHD },
 562                         { "debug-job", required_argument, &signal, DBG_JOB },
 563                         { "debug-cfg", required_argument, &signal, DBG_CFG },
 564                         { "debug-knl", required_argument, &signal, DBG_KNL },
 565                         { "debug-net", required_argument, &signal, DBG_NET },
 566                         { "debug-enc", required_argument, &signal, DBG_ENC },
 567                         { "debug-lib", required_argument, &signal, DBG_LIB },
 568                         { 0,0,0,0 }
 569                 };
 570
 571                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 572                 switch (c)
 573                 {
 574                         case EOF:
 575                         break;
 576                         case 'h':
 577                                 usage(NULL);
 578                                 break;
 579                         case 'v':
 580                                 printf("Linux strongSwan %s\n", VERSION);
 581                                 exit(0);
 582                         case 'l':
 583                                 use_syslog = TRUE;
 584                                 continue;
 585                         case 0:
 586                                 /* option is in signal */
 587                                 levels[signal] = atoi(optarg);
 588                                 continue;
 589                         default:
 590                                 usage("");
 591                                 break;
 592                 }
 593                 break;
 594         }
 595
 596         /* initialize daemon */
 597         if (!initialize(private_charon, use_syslog, levels))
 598         {
 599                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 600                 destroy(private_charon);
 601                 exit(-1);
 602         }
 603
 604         /* check/setup PID file */
 605         if (stat(PID_FILE, &stb) == 0)
 606         {
 607                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 608                 destroy(private_charon);
 609                 exit(-1);
 610         }
 611         pid_file = fopen(PID_FILE, "w");
 612         if (pid_file)
 613         {
 614                 fprintf(pid_file, "%d\n", getpid());
 615                 fchown(fileno(pid_file), charon->uid, charon->gid);
 616                 fclose(pid_file);
 617         }
 618
 619         /* drop additional capabilites (bind & root) */
 620         drop_capabilities(private_charon, TRUE);
 621
 622         /* start the engine, go multithreaded */
 623         charon->processor->set_threads(charon->processor,
 624                                                 lib->settings->get_int(lib->settings, "charon.threads",
 625                                                                                            DEFAULT_THREADS));
 626
 627         /* run daemon */
 628         run(private_charon);
 629
 630         /* normal termination, cleanup and exit */
 631         destroy(private_charon);
 632         unlink(PID_FILE);
 633
 634         library_deinit();
 635
 636         return 0;
 637 }
 638