source4/smbd/server.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Main SMB server routines
   5
   6    Copyright (C) Andrew Tridgell                1992-2005
   7    Copyright (C) Martin Pool                    2002
   8    Copyright (C) Jelmer Vernooij                2002
   9    Copyright (C) James J Myers                  2003 <myersjj@samba.org>
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "includes.h"
  26 #include "lib/events/events.h"
  27 #include "version.h"
  28 #include "lib/cmdline/popt_common.h"
  29 #include "system/dir.h"
  30 #include "system/filesys.h"
  31 #include "ntvfs/ntvfs.h"
  32 #include "ntptr/ntptr.h"
  33 #include "auth/gensec/gensec.h"
  34 #include "libcli/auth/schannel.h"
  35 #include "smbd/process_model.h"
  36 #include "param/secrets.h"
  37 #include "lib/util/pidfile.h"
  38 #include "param/param.h"
  39 #include "dsdb/samdb/samdb.h"
  40 #include "auth/session.h"
  41 #include "lib/messaging/irpc.h"
  42 #include "librpc/gen_ndr/ndr_irpc.h"
  43 #include "cluster/cluster.h"
  44 #include "dynconfig/dynconfig.h"
  45 #include "lib/util/samba_modules.h"
  46 #include "nsswitch/winbind_client.h"
  47
  48 /*
  49   recursively delete a directory tree
  50 */
  51 static void recursive_delete(const char *path)
  52 {
  53         DIR *dir;
  54         struct dirent *de;
  55
  56         dir = opendir(path);
  57         if (!dir) {
  58                 return;
  59         }
  60
  61         for (de=readdir(dir);de;de=readdir(dir)) {
  62                 char *fname;
  63                 struct stat st;
  64
  65                 if (ISDOT(de->d_name) || ISDOTDOT(de->d_name)) {
  66                         continue;
  67                 }
  68
  69                 fname = talloc_asprintf(path, "%s/%s", path, de->d_name);
  70                 if (stat(fname, &st) != 0) {
  71                         continue;
  72                 }
  73                 if (S_ISDIR(st.st_mode)) {
  74                         recursive_delete(fname);
  75                         talloc_free(fname);
  76                         continue;
  77                 }
  78                 if (unlink(fname) != 0) {
  79                         DEBUG(0,("Unabled to delete '%s' - %s\n",
  80                                  fname, strerror(errno)));
  81                         smb_panic("unable to cleanup tmp files");
  82                 }
  83                 talloc_free(fname);
  84         }
  85         closedir(dir);
  86 }
  87
  88 /*
  89   cleanup temporary files. This is the new alternative to
  90   TDB_CLEAR_IF_FIRST. Unfortunately TDB_CLEAR_IF_FIRST is not
  91   efficient on unix systems due to the lack of scaling of the byte
  92   range locking system. So instead of putting the burden on tdb to
  93   cleanup tmp files, this function deletes them.
  94 */
  95 static void cleanup_tmp_files(struct loadparm_context *lp_ctx)
  96 {
  97         char *path;
  98         TALLOC_CTX *mem_ctx = talloc_new(NULL);
  99
 100         path = smbd_tmp_path(mem_ctx, lp_ctx, NULL);
 101
 102         recursive_delete(path);
 103         talloc_free(mem_ctx);
 104 }
 105
 106 static void sig_hup(int sig)
 107 {
 108         debug_schedule_reopen_logs();
 109 }
 110
 111 static void sig_term(int sig)
 112 {
 113 #if HAVE_GETPGRP
 114         static int done_sigterm;
 115         if (done_sigterm == 0 && getpgrp() == getpid()) {
 116                 DEBUG(0,("SIGTERM: killing children\n"));
 117                 done_sigterm = 1;
 118                 kill(-getpgrp(), SIGTERM);
 119         }
 120 #endif
 121         DEBUG(0,("Exiting pid %d on SIGTERM\n", (int)getpid()));
 122         exit(127);
 123 }
 124
 125 /*
 126   setup signal masks
 127 */
 128 static void setup_signals(void)
 129 {
 130         /* we are never interested in SIGPIPE */
 131         BlockSignals(true,SIGPIPE);
 132
 133 #if defined(SIGFPE)
 134         /* we are never interested in SIGFPE */
 135         BlockSignals(true,SIGFPE);
 136 #endif
 137
 138         /* We are no longer interested in USR1 */
 139         BlockSignals(true, SIGUSR1);
 140
 141 #if defined(SIGUSR2)
 142         /* We are no longer interested in USR2 */
 143         BlockSignals(true,SIGUSR2);
 144 #endif
 145
 146         /* POSIX demands that signals are inherited. If the invoking process has
 147          * these signals masked, we will have problems, as we won't receive them. */
 148         BlockSignals(false, SIGHUP);
 149         BlockSignals(false, SIGTERM);
 150
 151         CatchSignal(SIGHUP, sig_hup);
 152         CatchSignal(SIGTERM, sig_term);
 153 }
 154
 155 /*
 156   handle io on stdin
 157 */
 158 static void server_stdin_handler(struct tevent_context *event_ctx, struct tevent_fd *fde,
 159                                  uint16_t flags, void *private_data)
 160 {
 161         const char *binary_name = (const char *)private_data;
 162         uint8_t c;
 163         if (read(0, &c, 1) == 0) {
 164                 DEBUG(0,("%s: EOF on stdin - terminating\n", binary_name));
 165 #if HAVE_GETPGRP
 166                 if (getpgrp() == getpid()) {
 167                         DEBUG(0,("Sending SIGTERM from pid %d\n", (int)getpid()));
 168                         kill(-getpgrp(), SIGTERM);
 169                 }
 170 #endif
 171                 exit(0);
 172         }
 173 }
 174
 175 /*
 176   die if the user selected maximum runtime is exceeded
 177 */
 178 _NORETURN_ static void max_runtime_handler(struct tevent_context *ev,
 179                                            struct tevent_timer *te,
 180                                            struct timeval t, void *private_data)
 181 {
 182         const char *binary_name = (const char *)private_data;
 183         DEBUG(0,("%s: maximum runtime exceeded - terminating at %llu, current ts: %llu\n",
 184                  binary_name, (unsigned long long)t.tv_sec, (unsigned long long) time(NULL)));
 185         exit(0);
 186 }
 187
 188 /*
 189   pre-open the key databases. This saves a lot of time in child
 190   processes
 191  */
 192 static void prime_ldb_databases(struct tevent_context *event_ctx)
 193 {
 194         TALLOC_CTX *db_context;
 195         db_context = talloc_new(event_ctx);
 196
 197         samdb_connect(db_context, event_ctx, cmdline_lp_ctx, system_session(cmdline_lp_ctx), 0);
 198         privilege_connect(db_context, cmdline_lp_ctx);
 199
 200         /* we deliberately leave these open, which allows them to be
 201          * re-used in ldb_wrap_connect() */
 202 }
 203
 204
 205 /*
 206   called when a fatal condition occurs in a child task
 207  */
 208 static NTSTATUS samba_terminate(struct irpc_message *msg,
 209                                 struct samba_terminate *r)
 210 {
 211         DEBUG(0,("samba_terminate: %s\n", r->in.reason));
 212         exit(1);
 213 }
 214
 215 /*
 216   setup messaging for the top level samba (parent) task
 217  */
 218 static NTSTATUS setup_parent_messaging(struct tevent_context *event_ctx,
 219                                        struct loadparm_context *lp_ctx)
 220 {
 221         struct imessaging_context *msg;
 222         NTSTATUS status;
 223
 224         msg = imessaging_init(talloc_autofree_context(),
 225                               lp_ctx,
 226                               cluster_id(0, SAMBA_PARENT_TASKID), event_ctx, false);
 227         NT_STATUS_HAVE_NO_MEMORY(msg);
 228
 229         status = irpc_add_name(msg, "samba");
 230         if (!NT_STATUS_IS_OK(status)) {
 231                 return status;
 232         }
 233
 234         status = IRPC_REGISTER(msg, irpc, SAMBA_TERMINATE,
 235                                samba_terminate, NULL);
 236
 237         return status;
 238 }
 239
 240
 241 /*
 242   show build info
 243  */
 244 static void show_build(void)
 245 {
 246 #define CONFIG_OPTION(n) { #n, dyn_ ## n }
 247         struct {
 248                 const char *name;
 249                 const char *value;
 250         } config_options[] = {
 251                 CONFIG_OPTION(BINDIR),
 252                 CONFIG_OPTION(SBINDIR),
 253                 CONFIG_OPTION(CONFIGFILE),
 254                 CONFIG_OPTION(NCALRPCDIR),
 255                 CONFIG_OPTION(LOGFILEBASE),
 256                 CONFIG_OPTION(LMHOSTSFILE),
 257                 CONFIG_OPTION(DATADIR),
 258                 CONFIG_OPTION(MODULESDIR),
 259                 CONFIG_OPTION(LOCKDIR),
 260                 CONFIG_OPTION(STATEDIR),
 261                 CONFIG_OPTION(CACHEDIR),
 262                 CONFIG_OPTION(PIDDIR),
 263                 CONFIG_OPTION(PRIVATE_DIR),
 264                 CONFIG_OPTION(CODEPAGEDIR),
 265                 CONFIG_OPTION(SETUPDIR),
 266                 CONFIG_OPTION(WINBINDD_SOCKET_DIR),
 267                 CONFIG_OPTION(WINBINDD_PRIVILEGED_SOCKET_DIR),
 268                 CONFIG_OPTION(NTP_SIGND_SOCKET_DIR),
 269                 { NULL, NULL}
 270         };
 271         int i;
 272
 273         printf("Samba version: %s\n", SAMBA_VERSION_STRING);
 274         printf("Build environment:\n");
 275 #ifdef BUILD_SYSTEM
 276         printf("   Build host:  %s\n", BUILD_SYSTEM);
 277 #endif
 278
 279         printf("Paths:\n");
 280         for (i=0; config_options[i].name; i++) {
 281                 printf("   %s: %s\n", config_options[i].name, config_options[i].value);
 282         }
 283
 284         exit(0);
 285 }
 286
 287 /*
 288  main server.
 289 */
 290 static int binary_smbd_main(const char *binary_name, int argc, const char *argv[])
 291 {
 292         bool opt_daemon = false;
 293         bool opt_interactive = false;
 294         int opt;
 295         poptContext pc;
 296 #define _MODULE_PROTO(init) extern NTSTATUS init(void);
 297         STATIC_service_MODULES_PROTO;
 298         init_module_fn static_init[] = { STATIC_service_MODULES };
 299         init_module_fn *shared_init;
 300         struct tevent_context *event_ctx;
 301         uint16_t stdin_event_flags;
 302         NTSTATUS status;
 303         const char *model = "standard";
 304         int max_runtime = 0;
 305         struct stat st;
 306         enum {
 307                 OPT_DAEMON = 1000,
 308                 OPT_INTERACTIVE,
 309                 OPT_PROCESS_MODEL,
 310                 OPT_SHOW_BUILD
 311         };
 312         struct poptOption long_options[] = {
 313                 POPT_AUTOHELP
 314                 {"daemon", 'D', POPT_ARG_NONE, NULL, OPT_DAEMON,
 315                  "Become a daemon (default)", NULL },
 316                 {"interactive", 'i', POPT_ARG_NONE, NULL, OPT_INTERACTIVE,
 317                  "Run interactive (not a daemon)", NULL},
 318                 {"model", 'M', POPT_ARG_STRING, NULL, OPT_PROCESS_MODEL,
 319                  "Select process model", "MODEL"},
 320                 {"maximum-runtime",0, POPT_ARG_INT, &max_runtime, 0,
 321                  "set maximum runtime of the server process, till autotermination", "seconds"},
 322                 {"show-build", 'b', POPT_ARG_NONE, NULL, OPT_SHOW_BUILD, "show build info", NULL },
 323                 POPT_COMMON_SAMBA
 324                 POPT_COMMON_VERSION
 325                 { NULL }
 326         };
 327
 328         pc = poptGetContext(binary_name, argc, argv, long_options, 0);
 329         while((opt = poptGetNextOpt(pc)) != -1) {
 330                 switch(opt) {
 331                 case OPT_DAEMON:
 332                         opt_daemon = true;
 333                         break;
 334                 case OPT_INTERACTIVE:
 335                         opt_interactive = true;
 336                         break;
 337                 case OPT_PROCESS_MODEL:
 338                         model = poptGetOptArg(pc);
 339                         break;
 340                 case OPT_SHOW_BUILD:
 341                         show_build();
 342                         break;
 343                 default:
 344                         fprintf(stderr, "\nInvalid option %s: %s\n\n",
 345                                   poptBadOption(pc, 0), poptStrerror(opt));
 346                         poptPrintUsage(pc, stderr, 0);
 347                         return 1;
 348                 }
 349         }
 350
 351         if (opt_daemon && opt_interactive) {
 352                 fprintf(stderr,"\nERROR: "
 353                           "Option -i|--interactive is not allowed together with -D|--daemon\n\n");
 354                 poptPrintUsage(pc, stderr, 0);
 355                 return 1;
 356         } else if (!opt_interactive) {
 357                 /* default is --daemon */
 358                 opt_daemon = true;
 359         }
 360
 361         poptFreeContext(pc);
 362
 363         talloc_enable_null_tracking();
 364
 365         setup_logging(binary_name, opt_interactive?DEBUG_STDOUT:DEBUG_FILE);
 366         setup_signals();
 367
 368         /* we want total control over the permissions on created files,
 369            so set our umask to 0 */
 370         umask(0);
 371
 372         DEBUG(0,("%s version %s started.\n", binary_name, SAMBA_VERSION_STRING));
 373         DEBUGADD(0,("Copyright Andrew Tridgell and the Samba Team 1992-2015\n"));
 374
 375         if (sizeof(uint16_t) < 2 || sizeof(uint32_t) < 4 || sizeof(uint64_t) < 8) {
 376                 DEBUG(0,("ERROR: Samba is not configured correctly for the word size on your machine\n"));
 377                 DEBUGADD(0,("sizeof(uint16_t) = %u, sizeof(uint32_t) %u, sizeof(uint64_t) = %u\n",
 378                             (unsigned int)sizeof(uint16_t), (unsigned int)sizeof(uint32_t), (unsigned int)sizeof(uint64_t)));
 379                 return 1;
 380         }
 381
 382         if (opt_daemon) {
 383                 DEBUG(3,("Becoming a daemon.\n"));
 384                 become_daemon(true, false, false);
 385         }
 386
 387         cleanup_tmp_files(cmdline_lp_ctx);
 388
 389         if (!directory_exist(lpcfg_lock_directory(cmdline_lp_ctx))) {
 390                 mkdir(lpcfg_lock_directory(cmdline_lp_ctx), 0755);
 391         }
 392
 393         pidfile_create(lpcfg_pid_directory(cmdline_lp_ctx), binary_name);
 394
 395         /* Set up a database to hold a random seed, in case we don't
 396          * have /dev/urandom */
 397         if (!randseed_init(talloc_autofree_context(), cmdline_lp_ctx)) {
 398                 return 1;
 399         }
 400
 401         if (lpcfg_server_role(cmdline_lp_ctx) == ROLE_ACTIVE_DIRECTORY_DC) {
 402                 if (!open_schannel_session_store(talloc_autofree_context(), cmdline_lp_ctx)) {
 403                         exit_daemon("Samba cannot open schannel store for secured NETLOGON operations.", EACCES);
 404                 }
 405         }
 406
 407         /* make sure we won't go through nss_winbind */
 408         if (!winbind_off()) {
 409                 exit_daemon("Samba failed to disable recusive winbindd calls.", EACCES);
 410         }
 411
 412         gensec_init(); /* FIXME: */
 413
 414         ntptr_init();   /* FIXME: maybe run this in the initialization function
 415                                                 of the spoolss RPC server instead? */
 416
 417         ntvfs_init(cmdline_lp_ctx);     /* FIXME: maybe run this in the initialization functions
 418                                                 of the SMB[,2] server instead? */
 419
 420         process_model_init(cmdline_lp_ctx);
 421
 422         shared_init = load_samba_modules(NULL, "service");
 423
 424         run_init_functions(static_init);
 425         run_init_functions(shared_init);
 426
 427         talloc_free(shared_init);
 428
 429         /* the event context is the top level structure in smbd. Everything else
 430            should hang off that */
 431         event_ctx = s4_event_context_init(talloc_autofree_context());
 432
 433         if (event_ctx == NULL) {
 434                 exit_daemon("Initializing event context failed", EACCES);
 435         }
 436
 437         if (opt_interactive) {
 438                 /* terminate when stdin goes away */
 439                 stdin_event_flags = TEVENT_FD_READ;
 440         } else {
 441                 /* stay alive forever */
 442                 stdin_event_flags = 0;
 443         }
 444
 445         /* catch EOF on stdin */
 446 #ifdef SIGTTIN
 447         signal(SIGTTIN, SIG_IGN);
 448 #endif
 449
 450         if (fstat(0, &st) != 0) {
 451                 exit_daemon("Samba failed to set standard input handler", ENOTTY);
 452         }
 453
 454         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode)) {
 455                 tevent_add_fd(event_ctx,
 456                                 event_ctx,
 457                                 0,
 458                                 stdin_event_flags,
 459                                 server_stdin_handler,
 460                                 discard_const(binary_name));
 461         }
 462
 463         if (max_runtime) {
 464                 DEBUG(0,("Called with maxruntime %d - current ts %llu\n",
 465                       max_runtime, (unsigned long long) time(NULL)));
 466                 tevent_add_timer(event_ctx, event_ctx,
 467                                  timeval_current_ofs(max_runtime, 0),
 468                                  max_runtime_handler,
 469                                  discard_const(binary_name));
 470         }
 471
 472         if (lpcfg_server_role(cmdline_lp_ctx) != ROLE_ACTIVE_DIRECTORY_DC
 473             && !lpcfg_parm_bool(cmdline_lp_ctx, NULL, "server role check", "inhibit", false)
 474             && !str_list_check_ci(lpcfg_server_services(cmdline_lp_ctx), "smb")
 475             && !str_list_check_ci(lpcfg_dcerpc_endpoint_servers(cmdline_lp_ctx), "remote")
 476             && !str_list_check_ci(lpcfg_dcerpc_endpoint_servers(cmdline_lp_ctx), "mapiproxy")) {
 477                 DEBUG(0, ("At this time the 'samba' binary should only be used for either:\n"));
 478                 DEBUGADD(0, ("'server role = active directory domain controller' or to access the ntvfs file server with 'server services = +smb' or the rpc proxy with 'dcerpc endpoint servers = remote'\n"));
 479                 DEBUGADD(0, ("You should start smbd/nmbd/winbindd instead for domain member and standalone file server tasks\n"));
 480                 exit_daemon("Samba detected misconfigured 'server role' and exited. Check logs for details", EINVAL);
 481         };
 482
 483         prime_ldb_databases(event_ctx);
 484
 485         status = setup_parent_messaging(event_ctx, cmdline_lp_ctx);
 486         if (!NT_STATUS_IS_OK(status)) {
 487                 exit_daemon("Samba failed to setup parent messaging", NT_STATUS_V(status));
 488         }
 489
 490         DEBUG(0,("%s: using '%s' process model\n", binary_name, model));
 491
 492         status = server_service_startup(event_ctx, cmdline_lp_ctx, model,
 493                                         lpcfg_server_services(cmdline_lp_ctx));
 494         if (!NT_STATUS_IS_OK(status)) {
 495                 exit_daemon("Samba failed to start services", NT_STATUS_V(status));
 496         }
 497
 498         if (opt_daemon) {
 499                 daemon_ready("samba");
 500         }
 501
 502         /* wait for events - this is where smbd sits for most of its
 503            life */
 504         tevent_loop_wait(event_ctx);
 505
 506         /* as everything hangs off this event context, freeing it
 507            should initiate a clean shutdown of all services */
 508         talloc_free(event_ctx);
 509
 510         return 0;
 511 }
 512
 513 int main(int argc, const char *argv[])
 514 {
 515         return binary_smbd_main("samba", argc, argv);
 516 }