src/charon/charon.c

   1 /*
   2  * Copyright (C) 2006-2012 Tobias Brunner
   3  * Copyright (C) 2005-2009 Martin Willi
   4  * Copyright (C) 2006 Daniel Roethlisberger
   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 #define _POSIX_PTHREAD_SEMANTICS /* for two param sigwait on OpenSolaris */
  21 #include <signal.h>
  22 #undef _POSIX_PTHREAD_SEMANTICS
  23 #include <pthread.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <sys/utsname.h>
  27 #include <unistd.h>
  28 #include <getopt.h>
  29
  30 #include <hydra.h>
  31 #include <daemon.h>
  32
  33 #include <library.h>
  34 #include <utils/backtrace.h>
  35 #include <threading/thread.h>
  36
  37 #ifdef ANDROID
  38 #include <private/android_filesystem_config.h> /* for AID_VPN */
  39 #endif
  40
  41 /**
  42  * PID file, in which charon stores its process id
  43  */
  44 #define PID_FILE IPSEC_PIDDIR "/charon.pid"
  45
  46 /**
  47  * Global reference to PID file (required to truncate, if undeletable)
  48  */
  49 static FILE *pidfile = NULL;
  50
  51 /**
  52  * Log levels as defined via command line arguments
  53  */
  54 static level_t levels[DBG_MAX];
  55
  56 /**
  57  * Whether to only use syslog when logging
  58  */
  59 static bool use_syslog = FALSE;
  60
  61 /**
  62  * hook in library for debugging messages
  63  */
  64 extern void (*dbg) (debug_t group, level_t level, char *fmt, ...);
  65
  66 /**
  67  * Logging hook for library logs, using stderr output
  68  */
  69 static void dbg_stderr(debug_t group, level_t level, char *fmt, ...)
  70 {
  71         va_list args;
  72
  73         if (level <= 1)
  74         {
  75                 va_start(args, fmt);
  76                 fprintf(stderr, "00[%N] ", debug_names, group);
  77                 vfprintf(stderr, fmt, args);
  78                 fprintf(stderr, "\n");
  79                 va_end(args);
  80         }
  81 }
  82
  83 /**
  84  * Run the daemon and handle unix signals
  85  */
  86 static void run()
  87 {
  88         sigset_t set;
  89
  90         /* handle SIGINT, SIGHUP ans SIGTERM in this handler */
  91         sigemptyset(&set);
  92         sigaddset(&set, SIGINT);
  93         sigaddset(&set, SIGHUP);
  94         sigaddset(&set, SIGTERM);
  95         sigprocmask(SIG_BLOCK, &set, NULL);
  96
  97         while (TRUE)
  98         {
  99                 int sig;
 100                 int error;
 101
 102                 error = sigwait(&set, &sig);
 103                 if (error)
 104                 {
 105                         DBG1(DBG_DMN, "error %d while waiting for a signal", error);
 106                         return;
 107                 }
 108                 switch (sig)
 109                 {
 110                         case SIGHUP:
 111                         {
 112                                 DBG1(DBG_DMN, "signal of type SIGHUP received. Reloading "
 113                                          "configuration");
 114                                 if (lib->settings->load_files(lib->settings, NULL, FALSE))
 115                                 {
 116                                         charon->load_loggers(charon, levels, !use_syslog);
 117                                         lib->plugins->reload(lib->plugins, NULL);
 118                                 }
 119                                 else
 120                                 {
 121                                         DBG1(DBG_DMN, "reloading config failed, keeping old");
 122                                 }
 123                                 break;
 124                         }
 125                         case SIGINT:
 126                         {
 127                                 DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
 128                                 charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 129                                 return;
 130                         }
 131                         case SIGTERM:
 132                         {
 133                                 DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
 134                                 charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 135                                 return;
 136                         }
 137                         default:
 138                         {
 139                                 DBG1(DBG_DMN, "unknown signal %d received. Ignored", sig);
 140                                 break;
 141                         }
 142                 }
 143         }
 144 }
 145
 146 /**
 147  * lookup UID and GID
 148  */
 149 static bool lookup_uid_gid()
 150 {
 151 #ifdef IPSEC_USER
 152         if (!lib->caps->resolve_uid(lib->caps, IPSEC_USER))
 153         {
 154                 return FALSE;
 155         }
 156 #endif
 157 #ifdef IPSEC_GROUP
 158         if (!lib->caps->resolve_gid(lib->caps, IPSEC_GROUP))
 159         {
 160                 return FALSE;
 161         }
 162 #endif
 163 #ifdef ANDROID
 164         lib->caps->set_uid(lib->caps, AID_VPN);
 165 #endif
 166         return TRUE;
 167 }
 168
 169 /**
 170  * Handle SIGSEGV/SIGILL signals raised by threads
 171  */
 172 static void segv_handler(int signal)
 173 {
 174         backtrace_t *backtrace;
 175
 176         DBG1(DBG_DMN, "thread %u received %d", thread_current_id(), signal);
 177         backtrace = backtrace_create(2);
 178         backtrace->log(backtrace, NULL, TRUE);
 179         backtrace->log(backtrace, stderr, TRUE);
 180         backtrace->destroy(backtrace);
 181
 182         DBG1(DBG_DMN, "killing ourself, received critical signal");
 183         abort();
 184 }
 185
 186 /**
 187  * Check/create PID file, return TRUE if already running
 188  */
 189 static bool check_pidfile()
 190 {
 191         struct stat stb;
 192
 193         if (stat(PID_FILE, &stb) == 0)
 194         {
 195                 pidfile = fopen(PID_FILE, "r");
 196                 if (pidfile)
 197                 {
 198                         char buf[64];
 199                         pid_t pid = 0;
 200
 201                         memset(buf, 0, sizeof(buf));
 202                         if (fread(buf, 1, sizeof(buf), pidfile))
 203                         {
 204                                 buf[sizeof(buf) - 1] = '\0';
 205                                 pid = atoi(buf);
 206                         }
 207                         fclose(pidfile);
 208                         if (pid && kill(pid, 0) == 0)
 209                         {       /* such a process is running */
 210                                 return TRUE;
 211                         }
 212                 }
 213                 DBG1(DBG_DMN, "removing pidfile '"PID_FILE"', process not running");
 214                 unlink(PID_FILE);
 215         }
 216
 217         /* create new pidfile */
 218         pidfile = fopen(PID_FILE, "w");
 219         if (pidfile)
 220         {
 221                 ignore_result(fchown(fileno(pidfile),
 222                                                          lib->caps->get_uid(lib->caps),
 223                                                          lib->caps->get_gid(lib->caps)));
 224                 fprintf(pidfile, "%d\n", getpid());
 225                 fflush(pidfile);
 226         }
 227         return FALSE;
 228 }
 229
 230 /**
 231  * Delete/truncate the PID file
 232  */
 233 static void unlink_pidfile()
 234 {
 235         /* because unlinking the PID file may fail, we truncate it to ensure the
 236          * daemon can be properly restarted.  one probable cause for this is the
 237          * combination of not running as root and the effective user lacking
 238          * permissions on the parent dir(s) of the PID file */
 239         if (pidfile)
 240         {
 241                 ignore_result(ftruncate(fileno(pidfile), 0));
 242                 fclose(pidfile);
 243         }
 244         unlink(PID_FILE);
 245 }
 246
 247 /**
 248  * print command line usage and exit
 249  */
 250 static void usage(const char *msg)
 251 {
 252         if (msg != NULL && *msg != '\0')
 253         {
 254                 fprintf(stderr, "%s\n", msg);
 255         }
 256         fprintf(stderr, "Usage: charon\n"
 257                                         "         [--help]\n"
 258                                         "         [--version]\n"
 259                                         "         [--use-syslog]\n"
 260                                         "         [--debug-<type> <level>]\n"
 261                                         "           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|asn|enc|tnc|imc|imv|pts|tls|esp|lib)\n"
 262                                         "           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
 263                                         "                                    2 = controlmore, 3 = raw, 4 = private)\n"
 264                                         "\n"
 265                    );
 266 }
 267
 268 /**
 269  * Main function, starts the daemon.
 270  */
 271 int main(int argc, char *argv[])
 272 {
 273         struct sigaction action;
 274         int group, status = SS_RC_INITIALIZATION_FAILED;
 275         struct utsname utsname;
 276
 277         /* logging for library during initialization, as we have no bus yet */
 278         dbg = dbg_stderr;
 279
 280         /* initialize library */
 281         if (!library_init(NULL))
 282         {
 283                 library_deinit();
 284                 exit(SS_RC_LIBSTRONGSWAN_INTEGRITY);
 285         }
 286
 287         if (lib->integrity &&
 288                 !lib->integrity->check_file(lib->integrity, "charon", argv[0]))
 289         {
 290                 dbg_stderr(DBG_DMN, 1, "integrity check of charon failed");
 291                 library_deinit();
 292                 exit(SS_RC_DAEMON_INTEGRITY);
 293         }
 294
 295         if (!libhydra_init("charon"))
 296         {
 297                 dbg_stderr(DBG_DMN, 1, "initialization failed - aborting charon");
 298                 libhydra_deinit();
 299                 library_deinit();
 300                 exit(SS_RC_INITIALIZATION_FAILED);
 301         }
 302
 303         if (!libcharon_init("charon"))
 304         {
 305                 dbg_stderr(DBG_DMN, 1, "initialization failed - aborting charon");
 306                 goto deinit;
 307         }
 308
 309         /* use CTRL loglevel for default */
 310         for (group = 0; group < DBG_MAX; group++)
 311         {
 312                 levels[group] = LEVEL_CTRL;
 313         }
 314
 315         /* handle arguments */
 316         for (;;)
 317         {
 318                 struct option long_opts[] = {
 319                         { "help", no_argument, NULL, 'h' },
 320                         { "version", no_argument, NULL, 'v' },
 321                         { "use-syslog", no_argument, NULL, 'l' },
 322                         /* TODO: handle "debug-all" */
 323                         { "debug-dmn", required_argument, &group, DBG_DMN },
 324                         { "debug-mgr", required_argument, &group, DBG_MGR },
 325                         { "debug-ike", required_argument, &group, DBG_IKE },
 326                         { "debug-chd", required_argument, &group, DBG_CHD },
 327                         { "debug-job", required_argument, &group, DBG_JOB },
 328                         { "debug-cfg", required_argument, &group, DBG_CFG },
 329                         { "debug-knl", required_argument, &group, DBG_KNL },
 330                         { "debug-net", required_argument, &group, DBG_NET },
 331                         { "debug-asn", required_argument, &group, DBG_ASN },
 332                         { "debug-enc", required_argument, &group, DBG_ENC },
 333                         { "debug-tnc", required_argument, &group, DBG_TNC },
 334                         { "debug-imc", required_argument, &group, DBG_IMC },
 335                         { "debug-imv", required_argument, &group, DBG_IMV },
 336                         { "debug-pts", required_argument, &group, DBG_PTS },
 337                         { "debug-tls", required_argument, &group, DBG_TLS },
 338                         { "debug-esp", required_argument, &group, DBG_ESP },
 339                         { "debug-lib", required_argument, &group, DBG_LIB },
 340                         { 0,0,0,0 }
 341                 };
 342
 343                 int c = getopt_long(argc, argv, "", long_opts, NULL);
 344                 switch (c)
 345                 {
 346                         case EOF:
 347                                 break;
 348                         case 'h':
 349                                 usage(NULL);
 350                                 status = 0;
 351                                 goto deinit;
 352                         case 'v':
 353                                 printf("Linux strongSwan %s\n", VERSION);
 354                                 status = 0;
 355                                 goto deinit;
 356                         case 'l':
 357                                 use_syslog = TRUE;
 358                                 continue;
 359                         case 0:
 360                                 /* option is in group */
 361                                 levels[group] = atoi(optarg);
 362                                 continue;
 363                         default:
 364                                 usage("");
 365                                 status = 1;
 366                                 goto deinit;
 367                 }
 368                 break;
 369         }
 370
 371         if (!lookup_uid_gid())
 372         {
 373                 dbg_stderr(DBG_DMN, 1, "invalid uid/gid - aborting charon");
 374                 goto deinit;
 375         }
 376
 377         charon->load_loggers(charon, levels, !use_syslog);
 378
 379         if (uname(&utsname) != 0)
 380         {
 381                 memset(&utsname, 0, sizeof(utsname));
 382         }
 383         DBG1(DBG_DMN, "Starting IKE charon daemon (strongSwan "VERSION", %s %s, %s)",
 384                   utsname.sysname, utsname.release, utsname.machine);
 385         if (lib->integrity)
 386         {
 387                 DBG1(DBG_DMN, "integrity tests enabled:");
 388                 DBG1(DBG_DMN, "lib    'libstrongswan': passed file and segment integrity tests");
 389                 DBG1(DBG_DMN, "lib    'libhydra': passed file and segment integrity tests");
 390                 DBG1(DBG_DMN, "lib    'libcharon': passed file and segment integrity tests");
 391                 DBG1(DBG_DMN, "daemon 'charon': passed file integrity test");
 392         }
 393
 394         /* initialize daemon */
 395         if (!charon->initialize(charon,
 396                                 lib->settings->get_str(lib->settings, "charon.load", PLUGINS)))
 397         {
 398                 DBG1(DBG_DMN, "initialization failed - aborting charon");
 399                 goto deinit;
 400         }
 401         lib->plugins->status(lib->plugins, LEVEL_CTRL);
 402
 403         if (check_pidfile())
 404         {
 405                 DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
 406                 goto deinit;
 407         }
 408
 409         if (!lib->caps->drop(lib->caps))
 410         {
 411                 DBG1(DBG_DMN, "capability dropping failed - aborting charon");
 412                 goto deinit;
 413         }
 414
 415         /* add handler for SEGV and ILL,
 416          * INT, TERM and HUP are handled by sigwait() in run() */
 417         action.sa_handler = segv_handler;
 418         action.sa_flags = 0;
 419         sigemptyset(&action.sa_mask);
 420         sigaddset(&action.sa_mask, SIGINT);
 421         sigaddset(&action.sa_mask, SIGTERM);
 422         sigaddset(&action.sa_mask, SIGHUP);
 423         sigaction(SIGSEGV, &action, NULL);
 424         sigaction(SIGILL, &action, NULL);
 425         sigaction(SIGBUS, &action, NULL);
 426         action.sa_handler = SIG_IGN;
 427         sigaction(SIGPIPE, &action, NULL);
 428
 429         pthread_sigmask(SIG_SETMASK, &action.sa_mask, NULL);
 430
 431         /* start daemon (i.e. the threads in the thread-pool) */
 432         charon->start(charon);
 433
 434         /* main thread goes to run loop */
 435         run();
 436
 437         /* normal termination, cleanup and exit */
 438         unlink_pidfile();
 439         status = 0;
 440
 441 deinit:
 442         libcharon_deinit();
 443         libhydra_deinit();
 444         library_deinit();
 445         return status;
 446 }
 447