source/winbindd/winbindd.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Winbind daemon for ntdom nss module
   5
   6    Copyright (C) by Tim Potter 2000-2002
   7    Copyright (C) Andrew Tridgell 2002
   8    Copyright (C) Jelmer Vernooij 2003
   9    Copyright (C) Volker Lendecke 2004
  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 "winbindd.h"
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_WINBIND
  30
  31 bool opt_nocache = False;
  32 static bool interactive = False;
  33
  34 extern bool override_logfile;
  35
  36 struct event_context *winbind_event_context(void)
  37 {
  38         static struct event_context *ctx;
  39
  40         if (!ctx && !(ctx = event_context_init(NULL))) {
  41                 smb_panic("Could not init winbind event context");
  42         }
  43         return ctx;
  44 }
  45
  46 struct messaging_context *winbind_messaging_context(void)
  47 {
  48         static struct messaging_context *ctx;
  49
  50         if (!ctx && !(ctx = messaging_init(NULL, server_id_self(),
  51                                            winbind_event_context()))) {
  52                 smb_panic("Could not init winbind messaging context");
  53         }
  54         return ctx;
  55 }
  56
  57 /* Reload configuration */
  58
  59 static bool reload_services_file(const char *logfile)
  60 {
  61         bool ret;
  62
  63         if (lp_loaded()) {
  64                 const char *fname = lp_configfile();
  65
  66                 if (file_exist(fname,NULL) && !strcsequal(fname,get_dyn_CONFIGFILE())) {
  67                         set_dyn_CONFIGFILE(fname);
  68                 }
  69         }
  70
  71         /* if this is a child, restore the logfile to the special
  72            name - <domain>, idmap, etc. */
  73         if (logfile && *logfile) {
  74                 lp_set_logfile(logfile);
  75         }
  76
  77         reopen_logs();
  78         ret = lp_load(get_dyn_CONFIGFILE(),False,False,True,True);
  79
  80         reopen_logs();
  81         load_interfaces();
  82
  83         return(ret);
  84 }
  85
  86
  87 /**************************************************************************** **
  88  Handle a fault..
  89  **************************************************************************** */
  90
  91 static void fault_quit(void)
  92 {
  93         dump_core();
  94 }
  95
  96 static void winbindd_status(void)
  97 {
  98         struct winbindd_cli_state *tmp;
  99
 100         DEBUG(0, ("winbindd status:\n"));
 101
 102         /* Print client state information */
 103
 104         DEBUG(0, ("\t%d clients currently active\n", winbindd_num_clients()));
 105
 106         if (DEBUGLEVEL >= 2 && winbindd_num_clients()) {
 107                 DEBUG(2, ("\tclient list:\n"));
 108                 for(tmp = winbindd_client_list(); tmp; tmp = tmp->next) {
 109                         DEBUGADD(2, ("\t\tpid %lu, sock %d\n",
 110                                   (unsigned long)tmp->pid, tmp->sock));
 111                 }
 112         }
 113 }
 114
 115 /* Print winbindd status to log file */
 116
 117 static void print_winbindd_status(void)
 118 {
 119         winbindd_status();
 120 }
 121
 122 /* Flush client cache */
 123
 124 static void flush_caches(void)
 125 {
 126         /* We need to invalidate cached user list entries on a SIGHUP
 127            otherwise cached access denied errors due to restrict anonymous
 128            hang around until the sequence number changes. */
 129
 130         if (!wcache_invalidate_cache()) {
 131                 DEBUG(0, ("invalidating the cache failed; revalidate the cache\n"));
 132                 if (!winbindd_cache_validate_and_initialize()) {
 133                         exit(1);
 134                 }
 135         }
 136 }
 137
 138 /* Handle the signal by unlinking socket and exiting */
 139
 140 static void terminate(bool is_parent)
 141 {
 142         if (is_parent) {
 143                 /* When parent goes away we should
 144                  * remove the socket file. Not so
 145                  * when children terminate.
 146                  */
 147                 char *path = NULL;
 148
 149                 if (asprintf(&path, "%s/%s",
 150                         get_winbind_pipe_dir(), WINBINDD_SOCKET_NAME) > 0) {
 151                         unlink(path);
 152                         SAFE_FREE(path);
 153                 }
 154         }
 155
 156         idmap_close();
 157
 158         trustdom_cache_shutdown();
 159
 160 #if 0
 161         if (interactive) {
 162                 TALLOC_CTX *mem_ctx = talloc_init("end_description");
 163                 char *description = talloc_describe_all(mem_ctx);
 164
 165                 DEBUG(3, ("tallocs left:\n%s\n", description));
 166                 talloc_destroy(mem_ctx);
 167         }
 168 #endif
 169
 170         exit(0);
 171 }
 172
 173 static SIG_ATOMIC_T do_sigterm = 0;
 174
 175 static void termination_handler(int signum)
 176 {
 177         do_sigterm = 1;
 178         sys_select_signal(signum);
 179 }
 180
 181 static SIG_ATOMIC_T do_sigusr2 = 0;
 182
 183 static void sigusr2_handler(int signum)
 184 {
 185         do_sigusr2 = 1;
 186         sys_select_signal(SIGUSR2);
 187 }
 188
 189 static SIG_ATOMIC_T do_sighup = 0;
 190
 191 static void sighup_handler(int signum)
 192 {
 193         do_sighup = 1;
 194         sys_select_signal(SIGHUP);
 195 }
 196
 197 static SIG_ATOMIC_T do_sigchld = 0;
 198
 199 static void sigchld_handler(int signum)
 200 {
 201         do_sigchld = 1;
 202         sys_select_signal(SIGCHLD);
 203 }
 204
 205 /* React on 'smbcontrol winbindd reload-config' in the same way as on SIGHUP*/
 206 static void msg_reload_services(struct messaging_context *msg,
 207                                 void *private_data,
 208                                 uint32_t msg_type,
 209                                 struct server_id server_id,
 210                                 DATA_BLOB *data)
 211 {
 212         /* Flush various caches */
 213         flush_caches();
 214         reload_services_file((const char *) private_data);
 215 }
 216
 217 /* React on 'smbcontrol winbindd shutdown' in the same way as on SIGTERM*/
 218 static void msg_shutdown(struct messaging_context *msg,
 219                          void *private_data,
 220                          uint32_t msg_type,
 221                          struct server_id server_id,
 222                          DATA_BLOB *data)
 223 {
 224         do_sigterm = 1;
 225 }
 226
 227
 228 static void winbind_msg_validate_cache(struct messaging_context *msg_ctx,
 229                                        void *private_data,
 230                                        uint32_t msg_type,
 231                                        struct server_id server_id,
 232                                        DATA_BLOB *data)
 233 {
 234         uint8 ret;
 235         pid_t child_pid;
 236         struct sigaction act;
 237         struct sigaction oldact;
 238
 239         DEBUG(10, ("winbindd_msg_validate_cache: got validate-cache "
 240                    "message.\n"));
 241
 242         /*
 243          * call the validation code from a child:
 244          * so we don't block the main winbindd and the validation
 245          * code can safely use fork/waitpid...
 246          */
 247         CatchChild();
 248         child_pid = sys_fork();
 249
 250         if (child_pid == -1) {
 251                 DEBUG(1, ("winbind_msg_validate_cache: Could not fork: %s\n",
 252                           strerror(errno)));
 253                 return;
 254         }
 255
 256         if (child_pid != 0) {
 257                 /* parent */
 258                 DEBUG(5, ("winbind_msg_validate_cache: child created with "
 259                           "pid %d.\n", child_pid));
 260                 return;
 261         }
 262
 263         /* child */
 264
 265         /* install default SIGCHLD handler: validation code uses fork/waitpid */
 266         ZERO_STRUCT(act);
 267         act.sa_handler = SIG_DFL;
 268 #ifdef SA_RESTART
 269         /* We *want* SIGALRM to interrupt a system call. */
 270         act.sa_flags = SA_RESTART;
 271 #endif
 272         sigemptyset(&act.sa_mask);
 273         sigaddset(&act.sa_mask,SIGCHLD);
 274         sigaction(SIGCHLD,&act,&oldact);
 275
 276         ret = (uint8)winbindd_validate_cache_nobackup();
 277         DEBUG(10, ("winbindd_msg_validata_cache: got return value %d\n", ret));
 278         messaging_send_buf(msg_ctx, server_id, MSG_WINBIND_VALIDATE_CACHE, &ret,
 279                            (size_t)1);
 280         _exit(0);
 281 }
 282
 283 static struct winbindd_dispatch_table {
 284         enum winbindd_cmd cmd;
 285         void (*fn)(struct winbindd_cli_state *state);
 286         const char *winbindd_cmd_name;
 287 } dispatch_table[] = {
 288
 289         /* User functions */
 290
 291         { WINBINDD_GETPWNAM, winbindd_getpwnam, "GETPWNAM" },
 292         { WINBINDD_GETPWUID, winbindd_getpwuid, "GETPWUID" },
 293
 294         { WINBINDD_SETPWENT, winbindd_setpwent, "SETPWENT" },
 295         { WINBINDD_ENDPWENT, winbindd_endpwent, "ENDPWENT" },
 296         { WINBINDD_GETPWENT, winbindd_getpwent, "GETPWENT" },
 297
 298         { WINBINDD_GETGROUPS, winbindd_getgroups, "GETGROUPS" },
 299         { WINBINDD_GETUSERSIDS, winbindd_getusersids, "GETUSERSIDS" },
 300         { WINBINDD_GETUSERDOMGROUPS, winbindd_getuserdomgroups,
 301           "GETUSERDOMGROUPS" },
 302
 303         /* Group functions */
 304
 305         { WINBINDD_GETGRNAM, winbindd_getgrnam, "GETGRNAM" },
 306         { WINBINDD_GETGRGID, winbindd_getgrgid, "GETGRGID" },
 307         { WINBINDD_SETGRENT, winbindd_setgrent, "SETGRENT" },
 308         { WINBINDD_ENDGRENT, winbindd_endgrent, "ENDGRENT" },
 309         { WINBINDD_GETGRENT, winbindd_getgrent, "GETGRENT" },
 310         { WINBINDD_GETGRLST, winbindd_getgrent, "GETGRLST" },
 311
 312         /* PAM auth functions */
 313
 314         { WINBINDD_PAM_AUTH, winbindd_pam_auth, "PAM_AUTH" },
 315         { WINBINDD_PAM_AUTH_CRAP, winbindd_pam_auth_crap, "AUTH_CRAP" },
 316         { WINBINDD_PAM_CHAUTHTOK, winbindd_pam_chauthtok, "CHAUTHTOK" },
 317         { WINBINDD_PAM_LOGOFF, winbindd_pam_logoff, "PAM_LOGOFF" },
 318         { WINBINDD_PAM_CHNG_PSWD_AUTH_CRAP, winbindd_pam_chng_pswd_auth_crap, "CHNG_PSWD_AUTH_CRAP" },
 319
 320         /* Enumeration functions */
 321
 322         { WINBINDD_LIST_USERS, winbindd_list_users, "LIST_USERS" },
 323         { WINBINDD_LIST_GROUPS, winbindd_list_groups, "LIST_GROUPS" },
 324         { WINBINDD_LIST_TRUSTDOM, winbindd_list_trusted_domains,
 325           "LIST_TRUSTDOM" },
 326         { WINBINDD_SHOW_SEQUENCE, winbindd_show_sequence, "SHOW_SEQUENCE" },
 327
 328         /* SID related functions */
 329
 330         { WINBINDD_LOOKUPSID, winbindd_lookupsid, "LOOKUPSID" },
 331         { WINBINDD_LOOKUPNAME, winbindd_lookupname, "LOOKUPNAME" },
 332         { WINBINDD_LOOKUPRIDS, winbindd_lookuprids, "LOOKUPRIDS" },
 333
 334         /* Lookup related functions */
 335
 336         { WINBINDD_SID_TO_UID, winbindd_sid_to_uid, "SID_TO_UID" },
 337         { WINBINDD_SID_TO_GID, winbindd_sid_to_gid, "SID_TO_GID" },
 338         { WINBINDD_UID_TO_SID, winbindd_uid_to_sid, "UID_TO_SID" },
 339         { WINBINDD_GID_TO_SID, winbindd_gid_to_sid, "GID_TO_SID" },
 340 #if 0   /* DISABLED until we fix the interface in Samba 3.0.26 --jerry */
 341         { WINBINDD_SIDS_TO_XIDS, winbindd_sids_to_unixids, "SIDS_TO_XIDS" },
 342 #endif  /* end DISABLED */
 343         { WINBINDD_ALLOCATE_UID, winbindd_allocate_uid, "ALLOCATE_UID" },
 344         { WINBINDD_ALLOCATE_GID, winbindd_allocate_gid, "ALLOCATE_GID" },
 345         { WINBINDD_SET_MAPPING, winbindd_set_mapping, "SET_MAPPING" },
 346         { WINBINDD_SET_HWM, winbindd_set_hwm, "SET_HWMS" },
 347
 348         /* Miscellaneous */
 349
 350         { WINBINDD_CHECK_MACHACC, winbindd_check_machine_acct, "CHECK_MACHACC" },
 351         { WINBINDD_PING, winbindd_ping, "PING" },
 352         { WINBINDD_INFO, winbindd_info, "INFO" },
 353         { WINBINDD_INTERFACE_VERSION, winbindd_interface_version,
 354           "INTERFACE_VERSION" },
 355         { WINBINDD_DOMAIN_NAME, winbindd_domain_name, "DOMAIN_NAME" },
 356         { WINBINDD_DOMAIN_INFO, winbindd_domain_info, "DOMAIN_INFO" },
 357         { WINBINDD_NETBIOS_NAME, winbindd_netbios_name, "NETBIOS_NAME" },
 358         { WINBINDD_PRIV_PIPE_DIR, winbindd_priv_pipe_dir,
 359           "WINBINDD_PRIV_PIPE_DIR" },
 360         { WINBINDD_GETDCNAME, winbindd_getdcname, "GETDCNAME" },
 361         { WINBINDD_DSGETDCNAME, winbindd_dsgetdcname, "DSGETDCNAME" },
 362
 363         /* Credential cache access */
 364         { WINBINDD_CCACHE_NTLMAUTH, winbindd_ccache_ntlm_auth, "NTLMAUTH" },
 365
 366         /* WINS functions */
 367
 368         { WINBINDD_WINS_BYNAME, winbindd_wins_byname, "WINS_BYNAME" },
 369         { WINBINDD_WINS_BYIP, winbindd_wins_byip, "WINS_BYIP" },
 370
 371         /* End of list */
 372
 373         { WINBINDD_NUM_CMDS, NULL, "NONE" }
 374 };
 375
 376 static void process_request(struct winbindd_cli_state *state)
 377 {
 378         struct winbindd_dispatch_table *table = dispatch_table;
 379
 380         /* Free response data - we may be interrupted and receive another
 381            command before being able to send this data off. */
 382
 383         SAFE_FREE(state->response.extra_data.data);
 384
 385         ZERO_STRUCT(state->response);
 386
 387         state->response.result = WINBINDD_PENDING;
 388         state->response.length = sizeof(struct winbindd_response);
 389
 390         state->mem_ctx = talloc_init("winbind request");
 391         if (state->mem_ctx == NULL)
 392                 return;
 393
 394         /* Remember who asked us. */
 395         state->pid = state->request.pid;
 396
 397         /* Process command */
 398
 399         for (table = dispatch_table; table->fn; table++) {
 400                 if (state->request.cmd == table->cmd) {
 401                         DEBUG(10,("process_request: request fn %s\n",
 402                                   table->winbindd_cmd_name ));
 403                         table->fn(state);
 404                         break;
 405                 }
 406         }
 407
 408         if (!table->fn) {
 409                 DEBUG(10,("process_request: unknown request fn number %d\n",
 410                           (int)state->request.cmd ));
 411                 request_error(state);
 412         }
 413 }
 414
 415 /*
 416  * A list of file descriptors being monitored by select in the main processing
 417  * loop. fd_event->handler is called whenever the socket is readable/writable.
 418  */
 419
 420 static struct fd_event *fd_events = NULL;
 421
 422 void add_fd_event(struct fd_event *ev)
 423 {
 424         struct fd_event *match;
 425
 426         /* only add unique fd_event structs */
 427
 428         for (match=fd_events; match; match=match->next ) {
 429 #ifdef DEVELOPER
 430                 SMB_ASSERT( match != ev );
 431 #else
 432                 if ( match == ev )
 433                         return;
 434 #endif
 435         }
 436
 437         DLIST_ADD(fd_events, ev);
 438 }
 439
 440 void remove_fd_event(struct fd_event *ev)
 441 {
 442         DLIST_REMOVE(fd_events, ev);
 443 }
 444
 445 /*
 446  * Handler for fd_events to complete a read/write request, set up by
 447  * setup_async_read/setup_async_write.
 448  */
 449
 450 static void rw_callback(struct fd_event *event, int flags)
 451 {
 452         size_t todo;
 453         ssize_t done = 0;
 454
 455         todo = event->length - event->done;
 456
 457         if (event->flags & EVENT_FD_WRITE) {
 458                 SMB_ASSERT(flags == EVENT_FD_WRITE);
 459                 done = sys_write(event->fd,
 460                                  &((char *)event->data)[event->done],
 461                                  todo);
 462
 463                 if (done <= 0) {
 464                         event->flags = 0;
 465                         event->finished(event->private_data, False);
 466                         return;
 467                 }
 468         }
 469
 470         if (event->flags & EVENT_FD_READ) {
 471                 SMB_ASSERT(flags == EVENT_FD_READ);
 472                 done = sys_read(event->fd, &((char *)event->data)[event->done],
 473                                 todo);
 474
 475                 if (done <= 0) {
 476                         event->flags = 0;
 477                         event->finished(event->private_data, False);
 478                         return;
 479                 }
 480         }
 481
 482         event->done += done;
 483
 484         if (event->done == event->length) {
 485                 event->flags = 0;
 486                 event->finished(event->private_data, True);
 487         }
 488 }
 489
 490 /*
 491  * Request an async read/write on a fd_event structure. (*finished) is called
 492  * when the request is completed or an error had occurred.
 493  */
 494
 495 void setup_async_read(struct fd_event *event, void *data, size_t length,
 496                       void (*finished)(void *private_data, bool success),
 497                       void *private_data)
 498 {
 499         SMB_ASSERT(event->flags == 0);
 500         event->data = data;
 501         event->length = length;
 502         event->done = 0;
 503         event->handler = rw_callback;
 504         event->finished = finished;
 505         event->private_data = private_data;
 506         event->flags = EVENT_FD_READ;
 507 }
 508
 509 void setup_async_write(struct fd_event *event, void *data, size_t length,
 510                        void (*finished)(void *private_data, bool success),
 511                        void *private_data)
 512 {
 513         SMB_ASSERT(event->flags == 0);
 514         event->data = data;
 515         event->length = length;
 516         event->done = 0;
 517         event->handler = rw_callback;
 518         event->finished = finished;
 519         event->private_data = private_data;
 520         event->flags = EVENT_FD_WRITE;
 521 }
 522
 523 /*
 524  * This is the main event loop of winbind requests. It goes through a
 525  * state-machine of 3 read/write requests, 4 if you have extra data to send.
 526  *
 527  * An idle winbind client has a read request of 4 bytes outstanding,
 528  * finalizing function is request_len_recv, checking the length. request_recv
 529  * then processes the packet. The processing function then at some point has
 530  * to call request_finished which schedules sending the response.
 531  */
 532
 533 static void request_len_recv(void *private_data, bool success);
 534 static void request_recv(void *private_data, bool success);
 535 static void request_main_recv(void *private_data, bool success);
 536 static void request_finished(struct winbindd_cli_state *state);
 537 void request_finished_cont(void *private_data, bool success);
 538 static void response_main_sent(void *private_data, bool success);
 539 static void response_extra_sent(void *private_data, bool success);
 540
 541 static void response_extra_sent(void *private_data, bool success)
 542 {
 543         struct winbindd_cli_state *state =
 544                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 545
 546         if (state->mem_ctx != NULL) {
 547                 talloc_destroy(state->mem_ctx);
 548                 state->mem_ctx = NULL;
 549         }
 550
 551         if (!success) {
 552                 state->finished = True;
 553                 return;
 554         }
 555
 556         SAFE_FREE(state->response.extra_data.data);
 557
 558         setup_async_read(&state->fd_event, &state->request, sizeof(uint32),
 559                          request_len_recv, state);
 560 }
 561
 562 static void response_main_sent(void *private_data, bool success)
 563 {
 564         struct winbindd_cli_state *state =
 565                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 566
 567         if (!success) {
 568                 state->finished = True;
 569                 return;
 570         }
 571
 572         if (state->response.length == sizeof(state->response)) {
 573                 if (state->mem_ctx != NULL) {
 574                         talloc_destroy(state->mem_ctx);
 575                         state->mem_ctx = NULL;
 576                 }
 577
 578                 setup_async_read(&state->fd_event, &state->request,
 579                                  sizeof(uint32), request_len_recv, state);
 580                 return;
 581         }
 582
 583         setup_async_write(&state->fd_event, state->response.extra_data.data,
 584                           state->response.length - sizeof(state->response),
 585                           response_extra_sent, state);
 586 }
 587
 588 static void request_finished(struct winbindd_cli_state *state)
 589 {
 590         /* Make sure request.extra_data is freed when finish processing a request */
 591         SAFE_FREE(state->request.extra_data.data);
 592         setup_async_write(&state->fd_event, &state->response,
 593                           sizeof(state->response), response_main_sent, state);
 594 }
 595
 596 void request_error(struct winbindd_cli_state *state)
 597 {
 598         SMB_ASSERT(state->response.result == WINBINDD_PENDING);
 599         state->response.result = WINBINDD_ERROR;
 600         request_finished(state);
 601 }
 602
 603 void request_ok(struct winbindd_cli_state *state)
 604 {
 605         SMB_ASSERT(state->response.result == WINBINDD_PENDING);
 606         state->response.result = WINBINDD_OK;
 607         request_finished(state);
 608 }
 609
 610 void request_finished_cont(void *private_data, bool success)
 611 {
 612         struct winbindd_cli_state *state =
 613                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 614
 615         if (success)
 616                 request_ok(state);
 617         else
 618                 request_error(state);
 619 }
 620
 621 static void request_len_recv(void *private_data, bool success)
 622 {
 623         struct winbindd_cli_state *state =
 624                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 625
 626         if (!success) {
 627                 state->finished = True;
 628                 return;
 629         }
 630
 631         if (*(uint32 *)(&state->request) != sizeof(state->request)) {
 632                 DEBUG(0,("request_len_recv: Invalid request size received: %d (expected %u)\n",
 633                          *(uint32_t *)(&state->request), (uint32_t)sizeof(state->request)));
 634                 state->finished = True;
 635                 return;
 636         }
 637
 638         setup_async_read(&state->fd_event, (uint32 *)(&state->request)+1,
 639                          sizeof(state->request) - sizeof(uint32),
 640                          request_main_recv, state);
 641 }
 642
 643 static void request_main_recv(void *private_data, bool success)
 644 {
 645         struct winbindd_cli_state *state =
 646                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 647
 648         if (!success) {
 649                 state->finished = True;
 650                 return;
 651         }
 652
 653         if (state->request.extra_len == 0) {
 654                 state->request.extra_data.data = NULL;
 655                 request_recv(state, True);
 656                 return;
 657         }
 658
 659         if ((!state->privileged) &&
 660             (state->request.extra_len > WINBINDD_MAX_EXTRA_DATA)) {
 661                 DEBUG(3, ("Got request with %d bytes extra data on "
 662                           "unprivileged socket\n", (int)state->request.extra_len));
 663                 state->request.extra_data.data = NULL;
 664                 state->finished = True;
 665                 return;
 666         }
 667
 668         state->request.extra_data.data =
 669                 SMB_MALLOC_ARRAY(char, state->request.extra_len + 1);
 670
 671         if (state->request.extra_data.data == NULL) {
 672                 DEBUG(0, ("malloc failed\n"));
 673                 state->finished = True;
 674                 return;
 675         }
 676
 677         /* Ensure null termination */
 678         state->request.extra_data.data[state->request.extra_len] = '\0';
 679
 680         setup_async_read(&state->fd_event, state->request.extra_data.data,
 681                          state->request.extra_len, request_recv, state);
 682 }
 683
 684 static void request_recv(void *private_data, bool success)
 685 {
 686         struct winbindd_cli_state *state =
 687                 talloc_get_type_abort(private_data, struct winbindd_cli_state);
 688
 689         if (!success) {
 690                 state->finished = True;
 691                 return;
 692         }
 693
 694         process_request(state);
 695 }
 696
 697 /* Process a new connection by adding it to the client connection list */
 698
 699 static void new_connection(int listen_sock, bool privileged)
 700 {
 701         struct sockaddr_un sunaddr;
 702         struct winbindd_cli_state *state;
 703         socklen_t len;
 704         int sock;
 705
 706         /* Accept connection */
 707
 708         len = sizeof(sunaddr);
 709
 710         do {
 711                 sock = accept(listen_sock, (struct sockaddr *)&sunaddr, &len);
 712         } while (sock == -1 && errno == EINTR);
 713
 714         if (sock == -1)
 715                 return;
 716
 717         DEBUG(6,("accepted socket %d\n", sock));
 718
 719         /* Create new connection structure */
 720
 721         if ((state = TALLOC_ZERO_P(NULL, struct winbindd_cli_state)) == NULL) {
 722                 close(sock);
 723                 return;
 724         }
 725
 726         state->sock = sock;
 727
 728         state->last_access = time(NULL);
 729
 730         state->privileged = privileged;
 731
 732         state->fd_event.fd = state->sock;
 733         state->fd_event.flags = 0;
 734         add_fd_event(&state->fd_event);
 735
 736         setup_async_read(&state->fd_event, &state->request, sizeof(uint32),
 737                          request_len_recv, state);
 738
 739         /* Add to connection list */
 740
 741         winbindd_add_client(state);
 742 }
 743
 744 /* Remove a client connection from client connection list */
 745
 746 static void remove_client(struct winbindd_cli_state *state)
 747 {
 748         char c = 0;
 749         int nwritten;
 750
 751         /* It's a dead client - hold a funeral */
 752
 753         if (state == NULL) {
 754                 return;
 755         }
 756
 757         /* tell client, we are closing ... */
 758         nwritten = write(state->sock, &c, sizeof(c));
 759         if (nwritten == -1) {
 760                 DEBUG(2, ("final write to client failed: %s\n",
 761                           strerror(errno)));
 762         }
 763
 764         /* Close socket */
 765
 766         close(state->sock);
 767
 768         /* Free any getent state */
 769
 770         free_getent_state(state->getpwent_state);
 771         free_getent_state(state->getgrent_state);
 772
 773         /* We may have some extra data that was not freed if the client was
 774            killed unexpectedly */
 775
 776         SAFE_FREE(state->response.extra_data.data);
 777
 778         if (state->mem_ctx != NULL) {
 779                 talloc_destroy(state->mem_ctx);
 780                 state->mem_ctx = NULL;
 781         }
 782
 783         remove_fd_event(&state->fd_event);
 784
 785         /* Remove from list and free */
 786
 787         winbindd_remove_client(state);
 788         TALLOC_FREE(state);
 789 }
 790
 791 /* Shutdown client connection which has been idle for the longest time */
 792
 793 static bool remove_idle_client(void)
 794 {
 795         struct winbindd_cli_state *state, *remove_state = NULL;
 796         time_t last_access = 0;
 797         int nidle = 0;
 798
 799         for (state = winbindd_client_list(); state; state = state->next) {
 800                 if (state->response.result != WINBINDD_PENDING &&
 801                     !state->getpwent_state && !state->getgrent_state) {
 802                         nidle++;
 803                         if (!last_access || state->last_access < last_access) {
 804                                 last_access = state->last_access;
 805                                 remove_state = state;
 806                         }
 807                 }
 808         }
 809
 810         if (remove_state) {
 811                 DEBUG(5,("Found %d idle client connections, shutting down sock %d, pid %u\n",
 812                         nidle, remove_state->sock, (unsigned int)remove_state->pid));
 813                 remove_client(remove_state);
 814                 return True;
 815         }
 816
 817         return False;
 818 }
 819
 820 /* check if HUP has been received and reload files */
 821 void winbind_check_sighup(const char *logfile)
 822 {
 823         if (do_sighup) {
 824
 825                 DEBUG(3, ("got SIGHUP\n"));
 826
 827                 flush_caches();
 828                 reload_services_file(logfile);
 829
 830                 do_sighup = 0;
 831         }
 832 }
 833
 834 /* check if TERM has been received */
 835 void winbind_check_sigterm(bool is_parent)
 836 {
 837         if (do_sigterm)
 838                 terminate(is_parent);
 839 }
 840
 841 /* Process incoming clients on listen_sock.  We use a tricky non-blocking,
 842    non-forking, non-threaded model which allows us to handle many
 843    simultaneous connections while remaining impervious to many denial of
 844    service attacks. */
 845
 846 static void process_loop(void)
 847 {
 848         struct winbindd_cli_state *state;
 849         struct fd_event *ev;
 850         fd_set r_fds, w_fds;
 851         int maxfd, listen_sock, listen_priv_sock, selret;
 852         struct timeval timeout, ev_timeout;
 853
 854         /* Open Sockets here to get stuff going ASAP */
 855         listen_sock = open_winbindd_socket();
 856         listen_priv_sock = open_winbindd_priv_socket();
 857
 858         if (listen_sock == -1 || listen_priv_sock == -1) {
 859                 perror("open_winbind_socket");
 860                 exit(1);
 861         }
 862
 863         /* We'll be doing this a lot */
 864
 865         /* Handle messages */
 866
 867         message_dispatch(winbind_messaging_context());
 868
 869         run_events(winbind_event_context(), 0, NULL, NULL);
 870
 871         /* refresh the trusted domain cache */
 872
 873         rescan_trusted_domains();
 874
 875         /* Initialise fd lists for select() */
 876
 877         maxfd = MAX(listen_sock, listen_priv_sock);
 878
 879         FD_ZERO(&r_fds);
 880         FD_ZERO(&w_fds);
 881         FD_SET(listen_sock, &r_fds);
 882         FD_SET(listen_priv_sock, &r_fds);
 883
 884         timeout.tv_sec = WINBINDD_ESTABLISH_LOOP;
 885         timeout.tv_usec = 0;
 886
 887         /* Check for any event timeouts. */
 888         if (get_timed_events_timeout(winbind_event_context(), &ev_timeout)) {
 889                 timeout = timeval_min(&timeout, &ev_timeout);
 890         }
 891
 892         /* Set up client readers and writers */
 893
 894         state = winbindd_client_list();
 895
 896         while (state) {
 897
 898                 struct winbindd_cli_state *next = state->next;
 899
 900                 /* Dispose of client connection if it is marked as
 901                    finished */
 902
 903                 if (state->finished)
 904                         remove_client(state);
 905
 906                 state = next;
 907         }
 908
 909         for (ev = fd_events; ev; ev = ev->next) {
 910                 if (ev->flags & EVENT_FD_READ) {
 911                         FD_SET(ev->fd, &r_fds);
 912                         maxfd = MAX(ev->fd, maxfd);
 913                 }
 914                 if (ev->flags & EVENT_FD_WRITE) {
 915                         FD_SET(ev->fd, &w_fds);
 916                         maxfd = MAX(ev->fd, maxfd);
 917                 }
 918         }
 919
 920         /* Call select */
 921
 922         selret = sys_select(maxfd + 1, &r_fds, &w_fds, NULL, &timeout);
 923
 924         if (selret == 0) {
 925                 goto no_fds_ready;
 926         }
 927
 928         if (selret == -1) {
 929                 if (errno == EINTR) {
 930                         goto no_fds_ready;
 931                 }
 932
 933                 /* Select error, something is badly wrong */
 934
 935                 perror("select");
 936                 exit(1);
 937         }
 938
 939         /* selret > 0 */
 940
 941         ev = fd_events;
 942         while (ev != NULL) {
 943                 struct fd_event *next = ev->next;
 944                 int flags = 0;
 945                 if (FD_ISSET(ev->fd, &r_fds))
 946                         flags |= EVENT_FD_READ;
 947                 if (FD_ISSET(ev->fd, &w_fds))
 948                         flags |= EVENT_FD_WRITE;
 949                 if (flags)
 950                         ev->handler(ev, flags);
 951                 ev = next;
 952         }
 953
 954         if (FD_ISSET(listen_sock, &r_fds)) {
 955                 while (winbindd_num_clients() >
 956                        WINBINDD_MAX_SIMULTANEOUS_CLIENTS - 1) {
 957                         DEBUG(5,("winbindd: Exceeding %d client "
 958                                  "connections, removing idle "
 959                                  "connection.\n",
 960                                  WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 961                         if (!remove_idle_client()) {
 962                                 DEBUG(0,("winbindd: Exceeding %d "
 963                                          "client connections, no idle "
 964                                          "connection found\n",
 965                                          WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 966                                 break;
 967                         }
 968                 }
 969                 /* new, non-privileged connection */
 970                 new_connection(listen_sock, False);
 971         }
 972
 973         if (FD_ISSET(listen_priv_sock, &r_fds)) {
 974                 while (winbindd_num_clients() >
 975                        WINBINDD_MAX_SIMULTANEOUS_CLIENTS - 1) {
 976                         DEBUG(5,("winbindd: Exceeding %d client "
 977                                  "connections, removing idle "
 978                                  "connection.\n",
 979                                  WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 980                         if (!remove_idle_client()) {
 981                                 DEBUG(0,("winbindd: Exceeding %d "
 982                                          "client connections, no idle "
 983                                          "connection found\n",
 984                                          WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 985                                 break;
 986                         }
 987                 }
 988                 /* new, privileged connection */
 989                 new_connection(listen_priv_sock, True);
 990         }
 991
 992  no_fds_ready:
 993
 994 #if 0
 995         winbindd_check_cache_size(time(NULL));
 996 #endif
 997
 998         /* Check signal handling things */
 999
1000         winbind_check_sigterm(true);
1001         winbind_check_sighup(NULL);
1002
1003         if (do_sigusr2) {
1004                 print_winbindd_status();
1005                 do_sigusr2 = 0;
1006         }
1007
1008         if (do_sigchld) {
1009                 pid_t pid;
1010
1011                 do_sigchld = 0;
1012
1013                 while ((pid = sys_waitpid(-1, NULL, WNOHANG)) > 0) {
1014                         winbind_child_died(pid);
1015                 }
1016         }
1017 }
1018
1019 /* Main function */
1020
1021 int main(int argc, char **argv, char **envp)
1022 {
1023         static bool is_daemon = False;
1024         static bool Fork = True;
1025         static bool log_stdout = False;
1026         static bool no_process_group = False;
1027         enum {
1028                 OPT_DAEMON = 1000,
1029                 OPT_FORK,
1030                 OPT_NO_PROCESS_GROUP,
1031                 OPT_LOG_STDOUT
1032         };
1033         struct poptOption long_options[] = {
1034                 POPT_AUTOHELP
1035                 { "stdout", 'S', POPT_ARG_NONE, NULL, OPT_LOG_STDOUT, "Log to stdout" },
1036                 { "foreground", 'F', POPT_ARG_NONE, NULL, OPT_FORK, "Daemon in foreground mode" },
1037                 { "no-process-group", 0, POPT_ARG_NONE, NULL, OPT_NO_PROCESS_GROUP, "Don't create a new process group" },
1038                 { "daemon", 'D', POPT_ARG_NONE, NULL, OPT_DAEMON, "Become a daemon (default)" },
1039                 { "interactive", 'i', POPT_ARG_NONE, NULL, 'i', "Interactive mode" },
1040                 { "no-caching", 'n', POPT_ARG_NONE, NULL, 'n', "Disable caching" },
1041                 POPT_COMMON_SAMBA
1042                 POPT_TABLEEND
1043         };
1044         poptContext pc;
1045         int opt;
1046         TALLOC_CTX *frame = talloc_stackframe();
1047
1048         /* glibc (?) likes to print "User defined signal 1" and exit if a
1049            SIGUSR[12] is received before a handler is installed */
1050
1051         CatchSignal(SIGUSR1, SIG_IGN);
1052         CatchSignal(SIGUSR2, SIG_IGN);
1053
1054         fault_setup((void (*)(void *))fault_quit );
1055         dump_core_setup("winbindd");
1056
1057         load_case_tables();
1058
1059         db_tdb2_setup_messaging(NULL, false);
1060
1061         /* Initialise for running in non-root mode */
1062
1063         sec_init();
1064
1065         set_remote_machine_name("winbindd", False);
1066
1067         /* Set environment variable so we don't recursively call ourselves.
1068            This may also be useful interactively. */
1069
1070         if ( !winbind_off() ) {
1071                 DEBUG(0,("Failed to disable recusive winbindd calls.  Exiting.\n"));
1072                 exit(1);
1073         }
1074
1075         /* Initialise samba/rpc client stuff */
1076
1077         pc = poptGetContext("winbindd", argc, (const char **)argv, long_options, 0);
1078
1079         while ((opt = poptGetNextOpt(pc)) != -1) {
1080                 switch (opt) {
1081                         /* Don't become a daemon */
1082                 case OPT_DAEMON:
1083                         is_daemon = True;
1084                         break;
1085                 case 'i':
1086                         interactive = True;
1087                         log_stdout = True;
1088                         Fork = False;
1089                         break;
1090                 case OPT_FORK:
1091                         Fork = false;
1092                         break;
1093                 case OPT_NO_PROCESS_GROUP:
1094                         no_process_group = true;
1095                         break;
1096                 case OPT_LOG_STDOUT:
1097                         log_stdout = true;
1098                         break;
1099                 case 'n':
1100                         opt_nocache = true;
1101                         break;
1102                 default:
1103                         d_fprintf(stderr, "\nInvalid option %s: %s\n\n",
1104                                   poptBadOption(pc, 0), poptStrerror(opt));
1105                         poptPrintUsage(pc, stderr, 0);
1106                         exit(1);
1107                 }
1108         }
1109
1110         if (is_daemon && interactive) {
1111                 d_fprintf(stderr,"\nERROR: "
1112                           "Option -i|--interactive is not allowed together with -D|--daemon\n\n");
1113                 poptPrintUsage(pc, stderr, 0);
1114                 exit(1);
1115         }
1116
1117         if (log_stdout && Fork) {
1118                 d_fprintf(stderr, "\nERROR: "
1119                           "Can't log to stdout (-S) unless daemon is in foreground +(-F) or interactive (-i)\n\n");
1120                 poptPrintUsage(pc, stderr, 0);
1121                 exit(1);
1122         }
1123
1124         poptFreeContext(pc);
1125
1126         if (!override_logfile) {
1127                 char *logfile = NULL;
1128                 if (asprintf(&logfile,"%s/log.winbindd",
1129                                 get_dyn_LOGFILEBASE()) > 0) {
1130                         lp_set_logfile(logfile);
1131                         SAFE_FREE(logfile);
1132                 }
1133         }
1134         setup_logging("winbindd", log_stdout);
1135         reopen_logs();
1136
1137         DEBUG(0,("winbindd version %s started.\n", SAMBA_VERSION_STRING));
1138         DEBUGADD(0,("%s\n", COPYRIGHT_STARTUP_MESSAGE));
1139
1140         if (!lp_load_initial_only(get_dyn_CONFIGFILE())) {
1141                 DEBUG(0, ("error opening config file\n"));
1142                 exit(1);
1143         }
1144
1145         /* Initialise messaging system */
1146
1147         if (winbind_messaging_context() == NULL) {
1148                 DEBUG(0, ("unable to initialize messaging system\n"));
1149                 exit(1);
1150         }
1151
1152         db_tdb2_setup_messaging(winbind_messaging_context(), true);
1153
1154         if (!reload_services_file(NULL)) {
1155                 DEBUG(0, ("error opening config file\n"));
1156                 exit(1);
1157         }
1158
1159         if (!directory_exist(lp_lockdir(), NULL)) {
1160                 mkdir(lp_lockdir(), 0755);
1161         }
1162
1163         /* Setup names. */
1164
1165         if (!init_names())
1166                 exit(1);
1167
1168         load_interfaces();
1169
1170         if (!secrets_init()) {
1171
1172                 DEBUG(0,("Could not initialize domain trust account secrets. Giving up\n"));
1173                 return False;
1174         }
1175
1176         /* Enable netbios namecache */
1177
1178         namecache_enable();
1179
1180         /* Winbind daemon initialisation */
1181
1182         if ( ! NT_STATUS_IS_OK(idmap_init_cache()) ) {
1183                 DEBUG(1, ("Could not init idmap cache!\n"));
1184         }
1185
1186         /* Unblock all signals we are interested in as they may have been
1187            blocked by the parent process. */
1188
1189         BlockSignals(False, SIGINT);
1190         BlockSignals(False, SIGQUIT);
1191         BlockSignals(False, SIGTERM);
1192         BlockSignals(False, SIGUSR1);
1193         BlockSignals(False, SIGUSR2);
1194         BlockSignals(False, SIGHUP);
1195         BlockSignals(False, SIGCHLD);
1196
1197         /* Setup signal handlers */
1198
1199         CatchSignal(SIGINT, termination_handler);      /* Exit on these sigs */
1200         CatchSignal(SIGQUIT, termination_handler);
1201         CatchSignal(SIGTERM, termination_handler);
1202         CatchSignal(SIGCHLD, sigchld_handler);
1203
1204         CatchSignal(SIGPIPE, SIG_IGN);                 /* Ignore sigpipe */
1205
1206         CatchSignal(SIGUSR2, sigusr2_handler);         /* Debugging sigs */
1207         CatchSignal(SIGHUP, sighup_handler);
1208
1209         if (!interactive)
1210                 become_daemon(Fork, no_process_group);
1211
1212         pidfile_create("winbindd");
1213
1214 #if HAVE_SETPGID
1215         /*
1216          * If we're interactive we want to set our own process group for
1217          * signal management.
1218          */
1219         if (interactive && !no_process_group)
1220                 setpgid( (pid_t)0, (pid_t)0);
1221 #endif
1222
1223         TimeInit();
1224
1225         if (!reinit_after_fork(winbind_messaging_context(), false)) {
1226                 DEBUG(0,("reinit_after_fork() failed\n"));
1227                 exit(1);
1228         }
1229
1230         /*
1231          * Ensure all cache and idmap caches are consistent
1232          * and initialized before we startup.
1233          */
1234         if (!winbindd_cache_validate_and_initialize()) {
1235                 exit(1);
1236         }
1237
1238         /* get broadcast messages */
1239         claim_connection(NULL,"",FLAG_MSG_GENERAL|FLAG_MSG_DBWRAP);
1240
1241         /* React on 'smbcontrol winbindd reload-config' in the same way
1242            as to SIGHUP signal */
1243         messaging_register(winbind_messaging_context(), NULL,
1244                            MSG_SMB_CONF_UPDATED, msg_reload_services);
1245         messaging_register(winbind_messaging_context(), NULL,
1246                            MSG_SHUTDOWN, msg_shutdown);
1247
1248         /* Handle online/offline messages. */
1249         messaging_register(winbind_messaging_context(), NULL,
1250                            MSG_WINBIND_OFFLINE, winbind_msg_offline);
1251         messaging_register(winbind_messaging_context(), NULL,
1252                            MSG_WINBIND_ONLINE, winbind_msg_online);
1253         messaging_register(winbind_messaging_context(), NULL,
1254                            MSG_WINBIND_ONLINESTATUS, winbind_msg_onlinestatus);
1255
1256         messaging_register(winbind_messaging_context(), NULL,
1257                            MSG_DUMP_EVENT_LIST, winbind_msg_dump_event_list);
1258
1259         messaging_register(winbind_messaging_context(), NULL,
1260                            MSG_WINBIND_VALIDATE_CACHE,
1261                            winbind_msg_validate_cache);
1262
1263         messaging_register(winbind_messaging_context(), NULL,
1264                            MSG_WINBIND_DUMP_DOMAIN_LIST,
1265                            winbind_msg_dump_domain_list);
1266
1267         /* Register handler for MSG_DEBUG. */
1268         messaging_register(winbind_messaging_context(), NULL,
1269                            MSG_DEBUG,
1270                            winbind_msg_debug);
1271
1272         netsamlogon_cache_init(); /* Non-critical */
1273
1274         /* clear the cached list of trusted domains */
1275
1276         wcache_tdc_clear();
1277
1278         if (!init_domain_list()) {
1279                 DEBUG(0,("unable to initialize domain list\n"));
1280                 exit(1);
1281         }
1282
1283         init_idmap_child();
1284         init_locator_child();
1285
1286         smb_nscd_flush_user_cache();
1287         smb_nscd_flush_group_cache();
1288
1289         /* Loop waiting for requests */
1290
1291         TALLOC_FREE(frame);
1292         while (1) {
1293                 frame = talloc_stackframe();
1294                 process_loop();
1295                 TALLOC_FREE(frame);
1296         }
1297
1298         return 0;
1299 }