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 <linux/capability.h>
  26 #include <sys/prctl.h>
  27 #include <signal.h>
  28 #include <pthread.h>
  29 #include <sys/stat.h>
  30 #include <sys/types.h>
  31 #include <unistd.h>
  32 #include <time.h>
  33 #include <string.h>
  34 #include <getopt.h>
  35 #include <errno.h>
  36 #include <pwd.h>
  37 #include <grp.h>
  38 #ifdef HAVE_BACKTRACE
  39 # include <execinfo.h>
  40 #endif /* HAVE_BACKTRACE */
  41
  42 #include "daemon.h"
  43
  44 #include <library.h>
  45 #include <config/traffic_selector.h>
  46 #include <config/proposal.h>
  47
  48 /* on some distros, a capset definition is missing */
  49 #ifdef NO_CAPSET_DEFINED
  50 extern int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
  51 #endif /* NO_CAPSET_DEFINED */
  52
  53 #ifdef INTEGRITY_TEST
  54 #include <fips/fips.h>
  55 #include <fips_signature.h>
  56 #endif /* INTEGRITY_TEST */
  57
  58 typedef struct private_daemon_t private_daemon_t;
  59
  60 /**
  61  * Private additions to daemon_t, contains threads and internal functions.
  62  */
  63 struct private_daemon_t {
  64         /**
  65          * Public members of daemon_t.
  66          */
  67         daemon_t public;
  68
  69         /**
  70          * Signal set used for signal handling.
  71          */
  72         sigset_t signal_set;
  73
  74         /**
  75          * The thread_id of main-thread.
  76          */
  77         pthread_t main_thread_id;
  78 };
  79
  80 /**
  81  * One and only instance of the daemon.
  82  */
  83 daemon_t *charon;
  84
  85 /**
  86  * hook in library for debugging messages
  87  */
  88 extern void (*dbg) (int level, char *fmt, ...);
  89
  90 /**
  91  * Logging hook for library logs, spreads debug message over bus
  92  */
  93 static void dbg_bus(int level, char *fmt, ...)
  94 {
  95         va_list args;
  96
  97         va_start(args, fmt);
  98         charon->bus->vsignal(charon->bus, DBG_LIB, level, fmt, args);
  99         va_end(args);
 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         if (level <= 1)
 110         {
 111                 va_start(args, fmt);
 112                 fprintf(stderr, "00[LIB] ");
 113                 vfprintf(stderr, fmt, args);
 114                 fprintf(stderr, "\n");
 115                 va_end(args);
 116         }
 117 }
 118
 119 /**
 120  * Run the daemon and handle unix signals
 121  */
 122 static void run(private_daemon_t *this)
 123 {
 124         sigset_t set;
 125
 126         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
 127         sigemptyset(&set);
 128         sigaddset(&set, SIGINT);
 129         sigaddset(&set, SIGHUP);
 130         sigaddset(&set, SIGTERM);
 131
 132         while (TRUE)
 133         {
 134                 int sig;
 135                 int error;
 136
 137                 error = sigwait(&set, &sig);
 138                 if (error)
 139                 {
 140                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 141                         return;
 142                 }
 143                 switch (sig)
 144                 {
 145                         case SIGHUP:
 146                         {
 147                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
 148                                 break;
 149                         }
 150                         case SIGINT:
 151                         {
 152                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 153                                 return;
 154                         }
 155                         case SIGTERM:
 156                         {
 157                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 158                                 return;
 159                         }
 160                         default:
 161                         {
 162                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 163                                 break;
 164                         }
 165                 }
 166         }
 167 }
 168
 169 /**
 170  * Clean up all daemon resources
 171  */
 172 static void destroy(private_daemon_t *this)
 173 {
 174         /* terminate all idle threads */
 175         if (this->public.processor)
 176         {
 177                 this->public.processor->set_threads(this->public.processor, 0);
 178         }
 179         /* close all IKE_SAs */
 180         if (this->public.ike_sa_manager)
 181         {
 182                 this->public.ike_sa_manager->flush(this->public.ike_sa_manager);
 183         }
 184         /* unload plugins to release threads */
 185         lib->plugins->unload(lib->plugins);
 186         DESTROY_IF(this->public.ike_sa_manager);
 187         DESTROY_IF(this->public.kernel_interface);
 188         DESTROY_IF(this->public.scheduler);
 189         DESTROY_IF(this->public.controller);
 190         DESTROY_IF(this->public.eap);
 191 #ifdef ME
 192         DESTROY_IF(this->public.connect_manager);
 193         DESTROY_IF(this->public.mediation_manager);
 194 #endif /* ME */
 195         DESTROY_IF(this->public.backends);
 196         DESTROY_IF(this->public.attributes);
 197         DESTROY_IF(this->public.credentials);
 198         DESTROY_IF(this->public.sender);
 199         DESTROY_IF(this->public.receiver);
 200         DESTROY_IF(this->public.socket);
 201         /* wait until all threads are gone */
 202         DESTROY_IF(this->public.processor);
 203
 204         /* rehook library logging, shutdown logging */
 205         dbg = dbg_stderr;
 206         DESTROY_IF(this->public.bus);
 207         DESTROY_IF(this->public.outlog);
 208         DESTROY_IF(this->public.syslog);
 209         DESTROY_IF(this->public.authlog);
 210         free(this);
 211 }
 212
 213 /**
 214  * Enforce daemon shutdown, with a given reason to do so.
 215  */
 216 static void kill_daemon(private_daemon_t *this, char *reason)
 217 {
 218         /* we send SIGTERM, so the daemon can cleanly shut down */
 219         if (this->public.bus)
 220         {
 221                 DBG1(DBG_DMN, "killing daemon: %s", reason);
 222         }
 223         else
 224         {
 225                 fprintf(stderr, "killing daemon: %s\n", reason);
 226         }
 227         if (this->main_thread_id == pthread_self())
 228         {
 229                 /* initialization failed, terminate daemon */
 230                 unlink(PID_FILE);
 231                 exit(-1);
 232         }
 233         else
 234         {
 235                 DBG1(DBG_DMN, "sending SIGTERM to ourself");
 236                 raise(SIGTERM);
 237                 /* thread must die, since he produced a ciritcal failure and can't continue */
 238                 pthread_exit(NULL);
 239         }
 240 }
 241
 242 /**
 243  * drop daemon capabilities
 244  */
 245 static void drop_capabilities(private_daemon_t *this, bool full)
 246 {
 247         struct __user_cap_header_struct hdr;
 248         struct __user_cap_data_struct data;
 249
 250         /* CAP_NET_ADMIN is needed to use netlink */
 251         u_int32_t keep = (1<<CAP_NET_ADMIN) | (1<<CAP_SYS_NICE);
 252
 253         if (full)
 254         {
 255                 if (setgid(charon->gid) != 0)
 256                 {
 257                         kill_daemon(this, "change to unprivileged group failed");
 258                 }
 259                 if (setuid(charon->uid) != 0)
 260                 {
 261                         kill_daemon(this, "change to unprivileged user failed");
 262                 }
 263         }
 264         else
 265         {
 266                 /* CAP_NET_BIND_SERVICE to bind services below port 1024 */
 267                 keep |= (1<<CAP_NET_BIND_SERVICE);
 268                 /* CAP_NET_RAW to create RAW sockets */
 269                 keep |= (1<<CAP_NET_RAW);
 270                 /* CAP_DAC_READ_SEARCH to read ipsec.secrets */
 271                 keep |= (1<<CAP_DAC_READ_SEARCH);
 272                 /* CAP_CHOWN to change file permissions (socket permissions) */
 273                 keep |= (1<<CAP_CHOWN);
 274                 /* CAP_SETUID to call setuid()  */
 275                 keep |= (1<<CAP_SETUID);
 276                 /* CAP_SETGID to call setgid() */
 277                 keep |= (1<<CAP_SETGID);
 278         }
 279
 280         /* we use the old capset version for now. For systems with version 2
 281          * available, we specifiy version 1 excplicitly. */
 282 #ifdef _LINUX_CAPABILITY_VERSION_1
 283         hdr.version = _LINUX_CAPABILITY_VERSION_1;
 284 #else
 285         hdr.version = _LINUX_CAPABILITY_VERSION;
 286 #endif
 287         hdr.pid = 0;
 288         data.inheritable = data.effective = data.permitted = keep;
 289
 290         if (capset(&hdr, &data))
 291         {
 292                 kill_daemon(this, "unable to drop daemon capabilities");
 293         }
 294 }
 295
 296 /**
 297  * lookup UID and GID
 298  */
 299 static void lookup_uid_gid(private_daemon_t *this)
 300 {
 301 #ifdef IPSEC_USER
 302         {
 303                 char buf[1024];
 304                 struct passwd passwd, *pwp;
 305
 306                 if (getpwnam_r(IPSEC_USER, &passwd, buf, sizeof(buf), &pwp) != 0 ||
 307                         pwp == NULL)
 308                 {
 309                         kill_daemon(this, "resolving user '"IPSEC_USER"' failed");
 310                 }
 311                 charon->uid = pwp->pw_uid;
 312         }
 313 #endif
 314 #ifdef IPSEC_GROUP
 315         {
 316                 char buf[1024];
 317                 struct group group, *grp;
 318
 319                 if (getgrnam_r(IPSEC_GROUP, &group, buf, sizeof(buf), &grp) != 0 ||
 320                         grp == NULL)
 321                 {
 322                         kill_daemon(this, "reslvoing group '"IPSEC_GROUP"' failed");
 323                 }
 324                 charon->gid = grp->gr_gid;
 325         }
 326 #endif
 327 }
 328
 329 /**
 330  * Initialize the daemon
 331  */
 332 static bool initialize(private_daemon_t *this, bool syslog, level_t levels[])
 333 {
 334         signal_t signal;
 335
 336         /* for uncritical pseudo random numbers */
 337         srandom(time(NULL) + getpid());
 338
 339         /* setup bus and it's listeners first to enable log output */
 340         this->public.bus = bus_create();
 341         this->public.outlog = file_logger_create(stdout);
 342         this->public.syslog = sys_logger_create(LOG_DAEMON);
 343         this->public.authlog = sys_logger_create(LOG_AUTHPRIV);
 344         this->public.bus->add_listener(this->public.bus, &this->public.syslog->listener);
 345         this->public.bus->add_listener(this->public.bus, &this->public.outlog->listener);
 346         this->public.bus->add_listener(this->public.bus, &this->public.authlog->listener);
 347         this->public.authlog->set_level(this->public.authlog, SIG_ANY, LEVEL_AUDIT);
 348         /* set up hook to log dbg message in library via charons message bus */
 349         dbg = dbg_bus;
 350
 351         /* apply loglevels */
 352         for (signal = 0; signal < DBG_MAX; signal++)
 353         {
 354                 this->public.syslog->set_level(this->public.syslog,
 355                                                                            signal, levels[signal]);
 356                 if (!syslog)
 357                 {
 358                         this->public.outlog->set_level(this->public.outlog,
 359                                                                                    signal, levels[signal]);
 360                 }
 361         }
 362
 363         DBG1(DBG_DMN, "starting charon (strongSwan Version %s)", VERSION);
 364
 365 #ifdef INTEGRITY_TEST
 366         DBG1(DBG_DMN, "integrity test of libstrongswan code");
 367         if (fips_verify_hmac_signature(hmac_key, hmac_signature))
 368         {
 369                 DBG1(DBG_DMN, "  integrity test passed");
 370         }
 371         else
 372         {
 373                 DBG1(DBG_DMN, "  integrity test failed");
 374                 return FALSE;
 375         }
 376 #endif /* INTEGRITY_TEST */
 377
 378         /* load secrets, ca certificates and crls */
 379         this->public.processor = processor_create();
 380         this->public.scheduler = scheduler_create();
 381         this->public.credentials = credential_manager_create();
 382         this->public.controller = controller_create();
 383         this->public.eap = eap_manager_create();
 384         this->public.backends = backend_manager_create();
 385         this->public.attributes = attribute_manager_create();
 386         this->public.kernel_interface = kernel_interface_create();
 387         this->public.socket = socket_create();
 388
 389         /* load plugins, further infrastructure may need it */
 390         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR,
 391                 lib->settings->get_str(lib->settings, "charon.load", PLUGINS));
 392
 393         this->public.ike_sa_manager = ike_sa_manager_create();
 394         if (this->public.ike_sa_manager == NULL)
 395         {
 396                 return FALSE;
 397         }
 398         this->public.sender = sender_create();
 399         this->public.receiver = receiver_create();
 400         if (this->public.receiver == NULL)
 401         {
 402                 return FALSE;
 403         }
 404
 405 #ifdef ME
 406         this->public.connect_manager = connect_manager_create();
 407         if (this->public.connect_manager == NULL)
 408         {
 409                 return FALSE;
 410         }
 411         this->public.mediation_manager = mediation_manager_create();
 412 #endif /* ME */
 413
 414         return TRUE;
 415 }
 416
 417 /**
 418  * Handle SIGSEGV/SIGILL signals raised by threads
 419  */
 420 static void segv_handler(int signal)
 421 {
 422 #ifdef HAVE_BACKTRACE
 423         void *array[20];
 424         size_t size;
 425         char **strings;
 426         size_t i;
 427
 428         size = backtrace(array, 20);
 429         strings = backtrace_symbols(array, size);
 430
 431         DBG1(DBG_JOB, "thread %u received %s. Dumping %d frames from stack:",
 432                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL", size);
 433
 434         for (i = 0; i < size; i++)
 435         {
 436 #ifdef HAVE_DLADDR
 437                 Dl_info info;
 438
 439                 if (dladdr(array[i], &info))
 440                 {
 441                         void *ptr = array[i];
 442                         if (strstr(info.dli_fname, ".so"))
 443                         {
 444                                 ptr = (void*)(array[i] - info.dli_fbase);
 445                         }
 446                         DBG1(DBG_DMN, "    %s [%p]", info.dli_fname, ptr);
 447                 }
 448                 else
 449                 {
 450 #endif /* HAVE_DLADDR */
 451                         DBG1(DBG_DMN, "    %s", strings[i]);
 452 #ifdef HAVE_DLADDR
 453                 }
 454 #endif /* HAVE_DLADDR */
 455         }
 456         free (strings);
 457 #else /* !HAVE_BACKTRACE */
 458         DBG1(DBG_DMN, "thread %u received %s",
 459                  pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
 460 #endif /* HAVE_BACKTRACE */
 461         DBG1(DBG_DMN, "killing ourself, received critical signal");
 462         raise(SIGKILL);
 463 }
 464
 465 /**
 466  * Create the daemon.
 467  */
 468 private_daemon_t *daemon_create(void)
 469 {
 470         struct sigaction action;
 471         private_daemon_t *this = malloc_thing(private_daemon_t);
 472
 473         /* assign methods */
 474         this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
 475
 476         /* NULL members for clean destruction */
 477         this->public.socket = NULL;
 478         this->public.ike_sa_manager = NULL;
 479         this->public.credentials = NULL;
 480         this->public.backends = NULL;
 481         this->public.attributes = NULL;
 482         this->public.sender= NULL;
 483         this->public.receiver = NULL;
 484         this->public.scheduler = NULL;
 485         this->public.kernel_interface = NULL;
 486         this->public.processor = NULL;
 487         this->public.controller = NULL;
 488         this->public.eap = NULL;
 489         this->public.bus = NULL;
 490         this->public.outlog = NULL;
 491         this->public.syslog = NULL;
 492         this->public.authlog = NULL;
 493 #ifdef ME
 494         this->public.connect_manager = NULL;
 495         this->public.mediation_manager = NULL;
 496 #endif /* ME */
 497         this->public.uid = 0;
 498         this->public.gid = 0;
 499
 500         this->main_thread_id = pthread_self();
 501
 502         /* add handler for SEGV and ILL,
 503          * add handler for USR1 (cancellation).
 504          * INT, TERM and HUP are handled by sigwait() in run() */
 505         action.sa_handler = segv_handler;
 506         action.sa_flags = 0;
 507         sigemptyset(&action.sa_mask);
 508         sigaddset(&action.sa_mask, SIGINT);
 509         sigaddset(&action.sa_mask, SIGTERM);
 510         sigaddset(&action.sa_mask, SIGHUP);
 511         sigaction(SIGSEGV, &action, NULL);
 512         sigaction(SIGILL, &action, NULL);
 513         action.sa_handler = SIG_IGN;
 514         sigaction(SIGPIPE, &action, NULL);
 515
 516         pthread_sigmask(SIG_SETMASK, &action.sa_mask, 0);
 517
 518         return this;
 519 }
 520
 521 /**
 522  * print command line usage and exit
 523  */
 524 static void usage(const char *msg)
 525 {
 526         if (msg != NULL && *msg != '\0')
 527         {
 528                 fprintf(stderr, "%s\n", msg);
 529         }
 530         fprintf(stderr, "Usage: charon\n"
 531                                         "         [--help]\n"
 532                                         "         [--version]\n"
 533                                         "         [--use-syslog]\n"
 534                                         "         [--debug-<type> <level>]\n"
 535                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
 536                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 537                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 538                                         "\n"
 539                    );
 540         exit(msg == NULL? 0 : 1);
 541 }
 542
 543 /**
 544  * Main function, manages the daemon.
 545  */
 546 int main(int argc, char *argv[])
 547 {
 548         bool use_syslog = FALSE;
 549
 550         private_daemon_t *private_charon;
 551         FILE *pid_file;
 552         struct stat stb;
 553         level_t levels[DBG_MAX];
 554         int signal;
 555
 556         /* logging for library during initialization, as we have no bus yet */
 557         dbg = dbg_stderr;
 558
 559         /* initialize library */
 560         library_init(STRONGSWAN_CONF);
 561         lib->printf_hook->add_handler(lib->printf_hook, 'R',
 562                                                                   traffic_selector_get_printf_hooks());
 563         lib->printf_hook->add_handler(lib->printf_hook, 'P',
 564                                                                   proposal_get_printf_hooks());
 565         private_charon = daemon_create();
 566         charon = (daemon_t*)private_charon;
 567
 568         lookup_uid_gid(private_charon);
 569
 570         /* drop the capabilities we won't need for initialization */
 571         prctl(PR_SET_KEEPCAPS, 1);
 572         drop_capabilities(private_charon, FALSE);
 573
 574         /* use CTRL loglevel for default */
 575         for (signal = 0; signal < DBG_MAX; signal++)
 576         {
 577                 levels[signal] = LEVEL_CTRL;
 578         }
 579
 580         /* handle arguments */
 581         for (;;)
 582         {
 583                 struct option long_opts[] = {
 584                         { "help", no_argument, NULL, 'h' },
 585                         { "version", no_argument, NULL, 'v' },
 586                         { "use-syslog", no_argument, NULL, 'l' },
 587                         /* TODO: handle "debug-all" */
 588                         { "debug-dmn", required_argument, &signal, DBG_DMN },
 589                         { "debug-mgr", required_argument, &signal, DBG_MGR },
 590                         { "debug-ike", required_argument, &signal, DBG_IKE },
 591                         { "debug-chd", required_argument, &signal, DBG_CHD },
 592                         { "debug-job", required_argument, &signal, DBG_JOB },
 593                         { "debug-cfg", required_argument, &signal, DBG_CFG },
 594                         { "debug-knl", required_argument, &signal, DBG_KNL },
 595                         { "debug-net", required_argument, &signal, DBG_NET },
 596                         { "debug-enc", required_argument, &signal, DBG_ENC },
 597                         { "debug-lib", required_argument, &signal, DBG_LIB },
 598                         { 0,0,0,0 }
 599                 };
 600
 601                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 602                 switch (c)
 603                 {
 604                         case EOF:
 605                         break;
 606                         case 'h':
 607                                 usage(NULL);
 608                                 break;
 609                         case 'v':
 610                                 printf("Linux strongSwan %s\n", VERSION);
 611                                 exit(0);
 612                         case 'l':
 613                                 use_syslog = TRUE;
 614                                 continue;
 615                         case 0:
 616                                 /* option is in signal */
 617                                 levels[signal] = atoi(optarg);
 618                                 continue;
 619                         default:
 620                                 usage("");
 621                                 break;
 622                 }
 623                 break;
 624         }
 625
 626         /* initialize daemon */
 627         if (!initialize(private_charon, use_syslog, levels))
 628         {
 629                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 630                 destroy(private_charon);
 631                 exit(-1);
 632         }
 633
 634         /* check/setup PID file */
 635         if (stat(PID_FILE, &stb) == 0)
 636         {
 637                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 638                 destroy(private_charon);
 639                 exit(-1);
 640         }
 641         pid_file = fopen(PID_FILE, "w");
 642         if (pid_file)
 643         {
 644                 fprintf(pid_file, "%d\n", getpid());
 645                 fchown(fileno(pid_file), charon->uid, charon->gid);
 646                 fclose(pid_file);
 647         }
 648
 649         /* drop additional capabilites (bind & root) */
 650         drop_capabilities(private_charon, TRUE);
 651
 652         /* start the engine, go multithreaded */
 653         charon->processor->set_threads(charon->processor,
 654                                                 lib->settings->get_int(lib->settings, "charon.threads",
 655                                                                                            DEFAULT_THREADS));
 656
 657         /* run daemon */
 658         run(private_charon);
 659
 660         /* normal termination, cleanup and exit */
 661         destroy(private_charon);
 662         unlink(PID_FILE);
 663
 664         library_deinit();
 665
 666         return 0;
 667 }
 668