source3/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 #include "../../nsswitch/libwbclient/wbc_async.h"
  28
  29 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_WINBIND
  31
  32 static void remove_client(struct winbindd_cli_state *state);
  33
  34 static bool opt_nocache = False;
  35 static bool interactive = False;
  36
  37 extern bool override_logfile;
  38
  39 struct event_context *winbind_event_context(void)
  40 {
  41         static struct event_context *ctx;
  42
  43         if (!ctx && !(ctx = event_context_init(NULL))) {
  44                 smb_panic("Could not init winbind event context");
  45         }
  46         return ctx;
  47 }
  48
  49 struct messaging_context *winbind_messaging_context(void)
  50 {
  51         static struct messaging_context *ctx;
  52
  53         if (ctx == NULL) {
  54                 ctx = messaging_init(NULL, server_id_self(),
  55                                      winbind_event_context());
  56         }
  57         if (ctx == NULL) {
  58                 DEBUG(0, ("Could not init winbind messaging context.\n"));
  59         }
  60         return ctx;
  61 }
  62
  63 /* Reload configuration */
  64
  65 static bool reload_services_file(const char *lfile)
  66 {
  67         bool ret;
  68
  69         if (lp_loaded()) {
  70                 const char *fname = lp_configfile();
  71
  72                 if (file_exist(fname) && !strcsequal(fname,get_dyn_CONFIGFILE())) {
  73                         set_dyn_CONFIGFILE(fname);
  74                 }
  75         }
  76
  77         /* if this is a child, restore the logfile to the special
  78            name - <domain>, idmap, etc. */
  79         if (lfile && *lfile) {
  80                 lp_set_logfile(lfile);
  81         }
  82
  83         reopen_logs();
  84         ret = lp_load(get_dyn_CONFIGFILE(),False,False,True,True);
  85
  86         reopen_logs();
  87         load_interfaces();
  88
  89         return(ret);
  90 }
  91
  92
  93 /**************************************************************************** **
  94  Handle a fault..
  95  **************************************************************************** */
  96
  97 static void fault_quit(void)
  98 {
  99         dump_core();
 100 }
 101
 102 static void winbindd_status(void)
 103 {
 104         struct winbindd_cli_state *tmp;
 105
 106         DEBUG(0, ("winbindd status:\n"));
 107
 108         /* Print client state information */
 109
 110         DEBUG(0, ("\t%d clients currently active\n", winbindd_num_clients()));
 111
 112         if (DEBUGLEVEL >= 2 && winbindd_num_clients()) {
 113                 DEBUG(2, ("\tclient list:\n"));
 114                 for(tmp = winbindd_client_list(); tmp; tmp = tmp->next) {
 115                         DEBUGADD(2, ("\t\tpid %lu, sock %d\n",
 116                                   (unsigned long)tmp->pid, tmp->sock));
 117                 }
 118         }
 119 }
 120
 121 /* Print winbindd status to log file */
 122
 123 static void print_winbindd_status(void)
 124 {
 125         winbindd_status();
 126 }
 127
 128 /* Flush client cache */
 129
 130 static void flush_caches(void)
 131 {
 132         /* We need to invalidate cached user list entries on a SIGHUP
 133            otherwise cached access denied errors due to restrict anonymous
 134            hang around until the sequence number changes. */
 135
 136         if (!wcache_invalidate_cache()) {
 137                 DEBUG(0, ("invalidating the cache failed; revalidate the cache\n"));
 138                 if (!winbindd_cache_validate_and_initialize()) {
 139                         exit(1);
 140                 }
 141         }
 142 }
 143
 144 /* Handle the signal by unlinking socket and exiting */
 145
 146 static void terminate(bool is_parent)
 147 {
 148         if (is_parent) {
 149                 /* When parent goes away we should
 150                  * remove the socket file. Not so
 151                  * when children terminate.
 152                  */
 153                 char *path = NULL;
 154
 155                 if (asprintf(&path, "%s/%s",
 156                         get_winbind_pipe_dir(), WINBINDD_SOCKET_NAME) > 0) {
 157                         unlink(path);
 158                         SAFE_FREE(path);
 159                 }
 160         }
 161
 162         idmap_close();
 163
 164         trustdom_cache_shutdown();
 165
 166         gencache_stabilize();
 167
 168 #if 0
 169         if (interactive) {
 170                 TALLOC_CTX *mem_ctx = talloc_init("end_description");
 171                 char *description = talloc_describe_all(mem_ctx);
 172
 173                 DEBUG(3, ("tallocs left:\n%s\n", description));
 174                 talloc_destroy(mem_ctx);
 175         }
 176 #endif
 177
 178         if (is_parent) {
 179                 pidfile_unlink();
 180         }
 181
 182         exit(0);
 183 }
 184
 185 static void winbindd_sig_term_handler(struct tevent_context *ev,
 186                                       struct tevent_signal *se,
 187                                       int signum,
 188                                       int count,
 189                                       void *siginfo,
 190                                       void *private_data)
 191 {
 192         bool *is_parent = talloc_get_type_abort(private_data, bool);
 193
 194         DEBUG(0,("Got sig[%d] terminate (is_parent=%d)\n",
 195                  signum, (int)*is_parent));
 196         terminate(*is_parent);
 197 }
 198
 199 bool winbindd_setup_sig_term_handler(bool parent)
 200 {
 201         struct tevent_signal *se;
 202         bool *is_parent;
 203
 204         is_parent = talloc(winbind_event_context(), bool);
 205         if (!is_parent) {
 206                 return false;
 207         }
 208
 209         *is_parent = parent;
 210
 211         se = tevent_add_signal(winbind_event_context(),
 212                                is_parent,
 213                                SIGTERM, 0,
 214                                winbindd_sig_term_handler,
 215                                is_parent);
 216         if (!se) {
 217                 DEBUG(0,("failed to setup SIGTERM handler"));
 218                 talloc_free(is_parent);
 219                 return false;
 220         }
 221
 222         se = tevent_add_signal(winbind_event_context(),
 223                                is_parent,
 224                                SIGINT, 0,
 225                                winbindd_sig_term_handler,
 226                                is_parent);
 227         if (!se) {
 228                 DEBUG(0,("failed to setup SIGINT handler"));
 229                 talloc_free(is_parent);
 230                 return false;
 231         }
 232
 233         se = tevent_add_signal(winbind_event_context(),
 234                                is_parent,
 235                                SIGQUIT, 0,
 236                                winbindd_sig_term_handler,
 237                                is_parent);
 238         if (!se) {
 239                 DEBUG(0,("failed to setup SIGINT handler"));
 240                 talloc_free(is_parent);
 241                 return false;
 242         }
 243
 244         return true;
 245 }
 246
 247 static void winbindd_sig_hup_handler(struct tevent_context *ev,
 248                                      struct tevent_signal *se,
 249                                      int signum,
 250                                      int count,
 251                                      void *siginfo,
 252                                      void *private_data)
 253 {
 254         const char *file = (const char *)private_data;
 255
 256         DEBUG(1,("Reloading services after SIGHUP\n"));
 257         flush_caches();
 258         reload_services_file(file);
 259 }
 260
 261 bool winbindd_setup_sig_hup_handler(const char *lfile)
 262 {
 263         struct tevent_signal *se;
 264         char *file = NULL;
 265
 266         if (lfile) {
 267                 file = talloc_strdup(winbind_event_context(),
 268                                      lfile);
 269                 if (!file) {
 270                         return false;
 271                 }
 272         }
 273
 274         se = tevent_add_signal(winbind_event_context(),
 275                                winbind_event_context(),
 276                                SIGHUP, 0,
 277                                winbindd_sig_hup_handler,
 278                                file);
 279         if (!se) {
 280                 return false;
 281         }
 282
 283         return true;
 284 }
 285
 286 static void winbindd_sig_chld_handler(struct tevent_context *ev,
 287                                       struct tevent_signal *se,
 288                                       int signum,
 289                                       int count,
 290                                       void *siginfo,
 291                                       void *private_data)
 292 {
 293         pid_t pid;
 294
 295         while ((pid = sys_waitpid(-1, NULL, WNOHANG)) > 0) {
 296                 winbind_child_died(pid);
 297         }
 298 }
 299
 300 static bool winbindd_setup_sig_chld_handler(void)
 301 {
 302         struct tevent_signal *se;
 303
 304         se = tevent_add_signal(winbind_event_context(),
 305                                winbind_event_context(),
 306                                SIGCHLD, 0,
 307                                winbindd_sig_chld_handler,
 308                                NULL);
 309         if (!se) {
 310                 return false;
 311         }
 312
 313         return true;
 314 }
 315
 316 static void winbindd_sig_usr2_handler(struct tevent_context *ev,
 317                                       struct tevent_signal *se,
 318                                       int signum,
 319                                       int count,
 320                                       void *siginfo,
 321                                       void *private_data)
 322 {
 323         print_winbindd_status();
 324 }
 325
 326 static bool winbindd_setup_sig_usr2_handler(void)
 327 {
 328         struct tevent_signal *se;
 329
 330         se = tevent_add_signal(winbind_event_context(),
 331                                winbind_event_context(),
 332                                SIGUSR2, 0,
 333                                winbindd_sig_usr2_handler,
 334                                NULL);
 335         if (!se) {
 336                 return false;
 337         }
 338
 339         return true;
 340 }
 341
 342 /* React on 'smbcontrol winbindd reload-config' in the same way as on SIGHUP*/
 343 static void msg_reload_services(struct messaging_context *msg,
 344                                 void *private_data,
 345                                 uint32_t msg_type,
 346                                 struct server_id server_id,
 347                                 DATA_BLOB *data)
 348 {
 349         /* Flush various caches */
 350         flush_caches();
 351         reload_services_file((const char *) private_data);
 352 }
 353
 354 /* React on 'smbcontrol winbindd shutdown' in the same way as on SIGTERM*/
 355 static void msg_shutdown(struct messaging_context *msg,
 356                          void *private_data,
 357                          uint32_t msg_type,
 358                          struct server_id server_id,
 359                          DATA_BLOB *data)
 360 {
 361         /* only the parent waits for this message */
 362         DEBUG(0,("Got shutdown message\n"));
 363         terminate(true);
 364 }
 365
 366
 367 static void winbind_msg_validate_cache(struct messaging_context *msg_ctx,
 368                                        void *private_data,
 369                                        uint32_t msg_type,
 370                                        struct server_id server_id,
 371                                        DATA_BLOB *data)
 372 {
 373         uint8 ret;
 374         pid_t child_pid;
 375         struct sigaction act;
 376         struct sigaction oldact;
 377
 378         DEBUG(10, ("winbindd_msg_validate_cache: got validate-cache "
 379                    "message.\n"));
 380
 381         /*
 382          * call the validation code from a child:
 383          * so we don't block the main winbindd and the validation
 384          * code can safely use fork/waitpid...
 385          */
 386         CatchChild();
 387         child_pid = sys_fork();
 388
 389         if (child_pid == -1) {
 390                 DEBUG(1, ("winbind_msg_validate_cache: Could not fork: %s\n",
 391                           strerror(errno)));
 392                 return;
 393         }
 394
 395         if (child_pid != 0) {
 396                 /* parent */
 397                 DEBUG(5, ("winbind_msg_validate_cache: child created with "
 398                           "pid %d.\n", (int)child_pid));
 399                 return;
 400         }
 401
 402         /* child */
 403
 404         /* install default SIGCHLD handler: validation code uses fork/waitpid */
 405         ZERO_STRUCT(act);
 406         act.sa_handler = SIG_DFL;
 407 #ifdef SA_RESTART
 408         /* We *want* SIGALRM to interrupt a system call. */
 409         act.sa_flags = SA_RESTART;
 410 #endif
 411         sigemptyset(&act.sa_mask);
 412         sigaddset(&act.sa_mask,SIGCHLD);
 413         sigaction(SIGCHLD,&act,&oldact);
 414
 415         ret = (uint8)winbindd_validate_cache_nobackup();
 416         DEBUG(10, ("winbindd_msg_validata_cache: got return value %d\n", ret));
 417         messaging_send_buf(msg_ctx, server_id, MSG_WINBIND_VALIDATE_CACHE, &ret,
 418                            (size_t)1);
 419         _exit(0);
 420 }
 421
 422 static struct winbindd_dispatch_table {
 423         enum winbindd_cmd cmd;
 424         void (*fn)(struct winbindd_cli_state *state);
 425         const char *winbindd_cmd_name;
 426 } dispatch_table[] = {
 427
 428         /* PAM auth functions */
 429
 430         { WINBINDD_PAM_AUTH, winbindd_pam_auth, "PAM_AUTH" },
 431         { WINBINDD_PAM_AUTH_CRAP, winbindd_pam_auth_crap, "AUTH_CRAP" },
 432         { WINBINDD_PAM_CHAUTHTOK, winbindd_pam_chauthtok, "CHAUTHTOK" },
 433         { WINBINDD_PAM_LOGOFF, winbindd_pam_logoff, "PAM_LOGOFF" },
 434         { WINBINDD_PAM_CHNG_PSWD_AUTH_CRAP, winbindd_pam_chng_pswd_auth_crap, "CHNG_PSWD_AUTH_CRAP" },
 435
 436         /* Enumeration functions */
 437
 438         { WINBINDD_LIST_TRUSTDOM, winbindd_list_trusted_domains,
 439           "LIST_TRUSTDOM" },
 440
 441         /* Lookup related functions */
 442
 443         { WINBINDD_SET_MAPPING, winbindd_set_mapping, "SET_MAPPING" },
 444         { WINBINDD_REMOVE_MAPPING, winbindd_remove_mapping, "REMOVE_MAPPING" },
 445         { WINBINDD_SET_HWM, winbindd_set_hwm, "SET_HWMS" },
 446
 447         /* Miscellaneous */
 448
 449         { WINBINDD_CHECK_MACHACC, winbindd_check_machine_acct, "CHECK_MACHACC" },
 450         { WINBINDD_INFO, winbindd_info, "INFO" },
 451         { WINBINDD_INTERFACE_VERSION, winbindd_interface_version,
 452           "INTERFACE_VERSION" },
 453         { WINBINDD_DOMAIN_NAME, winbindd_domain_name, "DOMAIN_NAME" },
 454         { WINBINDD_DOMAIN_INFO, winbindd_domain_info, "DOMAIN_INFO" },
 455         { WINBINDD_NETBIOS_NAME, winbindd_netbios_name, "NETBIOS_NAME" },
 456         { WINBINDD_PRIV_PIPE_DIR, winbindd_priv_pipe_dir,
 457           "WINBINDD_PRIV_PIPE_DIR" },
 458
 459         /* Credential cache access */
 460         { WINBINDD_CCACHE_NTLMAUTH, winbindd_ccache_ntlm_auth, "NTLMAUTH" },
 461
 462         /* WINS functions */
 463
 464         { WINBINDD_WINS_BYNAME, winbindd_wins_byname, "WINS_BYNAME" },
 465         { WINBINDD_WINS_BYIP, winbindd_wins_byip, "WINS_BYIP" },
 466
 467         /* End of list */
 468
 469         { WINBINDD_NUM_CMDS, NULL, "NONE" }
 470 };
 471
 472 struct winbindd_async_dispatch_table {
 473         enum winbindd_cmd cmd;
 474         const char *cmd_name;
 475         struct tevent_req *(*send_req)(TALLOC_CTX *mem_ctx,
 476                                        struct tevent_context *ev,
 477                                        struct winbindd_cli_state *cli,
 478                                        struct winbindd_request *request);
 479         NTSTATUS (*recv_req)(struct tevent_req *req,
 480                              struct winbindd_response *presp);
 481 };
 482
 483 static struct winbindd_async_dispatch_table async_nonpriv_table[] = {
 484         { WINBINDD_PING, "PING",
 485           wb_ping_send, wb_ping_recv },
 486         { WINBINDD_LOOKUPSID, "LOOKUPSID",
 487           winbindd_lookupsid_send, winbindd_lookupsid_recv },
 488         { WINBINDD_LOOKUPNAME, "LOOKUPNAME",
 489           winbindd_lookupname_send, winbindd_lookupname_recv },
 490         { WINBINDD_SID_TO_UID, "SID_TO_UID",
 491           winbindd_sid_to_uid_send, winbindd_sid_to_uid_recv },
 492         { WINBINDD_SID_TO_GID, "SID_TO_GID",
 493           winbindd_sid_to_gid_send, winbindd_sid_to_gid_recv },
 494         { WINBINDD_UID_TO_SID, "UID_TO_SID",
 495           winbindd_uid_to_sid_send, winbindd_uid_to_sid_recv },
 496         { WINBINDD_GID_TO_SID, "GID_TO_SID",
 497           winbindd_gid_to_sid_send, winbindd_gid_to_sid_recv },
 498         { WINBINDD_GETPWSID, "GETPWSID",
 499           winbindd_getpwsid_send, winbindd_getpwsid_recv },
 500         { WINBINDD_GETPWNAM, "GETPWNAM",
 501           winbindd_getpwnam_send, winbindd_getpwnam_recv },
 502         { WINBINDD_GETPWUID, "GETPWUID",
 503           winbindd_getpwuid_send, winbindd_getpwuid_recv },
 504         { WINBINDD_GETSIDALIASES, "GETSIDALIASES",
 505           winbindd_getsidaliases_send, winbindd_getsidaliases_recv },
 506         { WINBINDD_GETUSERDOMGROUPS, "GETUSERDOMGROUPS",
 507           winbindd_getuserdomgroups_send, winbindd_getuserdomgroups_recv },
 508         { WINBINDD_GETGROUPS, "GETGROUPS",
 509           winbindd_getgroups_send, winbindd_getgroups_recv },
 510         { WINBINDD_SHOW_SEQUENCE, "SHOW_SEQUENCE",
 511           winbindd_show_sequence_send, winbindd_show_sequence_recv },
 512         { WINBINDD_GETGRGID, "GETGRGID",
 513           winbindd_getgrgid_send, winbindd_getgrgid_recv },
 514         { WINBINDD_GETGRNAM, "GETGRNAM",
 515           winbindd_getgrnam_send, winbindd_getgrnam_recv },
 516         { WINBINDD_GETUSERSIDS, "GETUSERSIDS",
 517           winbindd_getusersids_send, winbindd_getusersids_recv },
 518         { WINBINDD_LOOKUPRIDS, "LOOKUPRIDS",
 519           winbindd_lookuprids_send, winbindd_lookuprids_recv },
 520         { WINBINDD_SETPWENT, "SETPWENT",
 521           winbindd_setpwent_send, winbindd_setpwent_recv },
 522         { WINBINDD_GETPWENT, "GETPWENT",
 523           winbindd_getpwent_send, winbindd_getpwent_recv },
 524         { WINBINDD_ENDPWENT, "ENDPWENT",
 525           winbindd_endpwent_send, winbindd_endpwent_recv },
 526         { WINBINDD_DSGETDCNAME, "DSGETDCNAME",
 527           winbindd_dsgetdcname_send, winbindd_dsgetdcname_recv },
 528         { WINBINDD_GETDCNAME, "GETDCNAME",
 529           winbindd_getdcname_send, winbindd_getdcname_recv },
 530         { WINBINDD_SETGRENT, "SETGRENT",
 531           winbindd_setgrent_send, winbindd_setgrent_recv },
 532         { WINBINDD_GETGRENT, "GETGRENT",
 533           winbindd_getgrent_send, winbindd_getgrent_recv },
 534         { WINBINDD_ENDGRENT, "ENDGRENT",
 535           winbindd_endgrent_send, winbindd_endgrent_recv },
 536         { WINBINDD_LIST_USERS, "LIST_USERS",
 537           winbindd_list_users_send, winbindd_list_users_recv },
 538         { WINBINDD_LIST_GROUPS, "LIST_GROUPS",
 539           winbindd_list_groups_send, winbindd_list_groups_recv },
 540
 541         { 0, NULL, NULL, NULL }
 542 };
 543
 544 static struct winbindd_async_dispatch_table async_priv_table[] = {
 545         { WINBINDD_ALLOCATE_UID, "ALLOCATE_UID",
 546           winbindd_allocate_uid_send, winbindd_allocate_uid_recv },
 547         { WINBINDD_ALLOCATE_GID, "ALLOCATE_GID",
 548           winbindd_allocate_gid_send, winbindd_allocate_gid_recv },
 549
 550         { 0, NULL, NULL, NULL }
 551 };
 552
 553 static void wb_request_done(struct tevent_req *req);
 554
 555 static void process_request(struct winbindd_cli_state *state)
 556 {
 557         struct winbindd_dispatch_table *table = dispatch_table;
 558         struct winbindd_async_dispatch_table *atable;
 559
 560         state->mem_ctx = talloc_init("winbind request");
 561         if (state->mem_ctx == NULL)
 562                 return;
 563
 564         /* Remember who asked us. */
 565         state->pid = state->request->pid;
 566
 567         /* Process command */
 568
 569         for (atable = async_nonpriv_table; atable->send_req; atable += 1) {
 570                 if (state->request->cmd == atable->cmd) {
 571                         break;
 572                 }
 573         }
 574
 575         if ((atable->send_req == NULL) && state->privileged) {
 576                 for (atable = async_priv_table; atable->send_req;
 577                      atable += 1) {
 578                         if (state->request->cmd == atable->cmd) {
 579                                 break;
 580                         }
 581                 }
 582         }
 583
 584         if (atable->send_req != NULL) {
 585                 struct tevent_req *req;
 586
 587                 DEBUG(10, ("process_request: Handling async request %s\n",
 588                            atable->cmd_name));
 589
 590                 req = atable->send_req(state->mem_ctx, winbind_event_context(),
 591                                        state, state->request);
 592                 if (req == NULL) {
 593                         DEBUG(0, ("process_request: atable->send failed for "
 594                                   "%s\n", atable->cmd_name));
 595                         request_error(state);
 596                         return;
 597                 }
 598                 tevent_req_set_callback(req, wb_request_done, state);
 599                 state->recv_fn = atable->recv_req;
 600                 return;
 601         }
 602
 603         state->response = talloc_zero(state->mem_ctx,
 604                                       struct winbindd_response);
 605         if (state->response == NULL) {
 606                 DEBUG(10, ("talloc failed\n"));
 607                 remove_client(state);
 608                 return;
 609         }
 610         state->response->result = WINBINDD_PENDING;
 611         state->response->length = sizeof(struct winbindd_response);
 612
 613         for (table = dispatch_table; table->fn; table++) {
 614                 if (state->request->cmd == table->cmd) {
 615                         DEBUG(10,("process_request: request fn %s\n",
 616                                   table->winbindd_cmd_name ));
 617                         table->fn(state);
 618                         break;
 619                 }
 620         }
 621
 622         if (!table->fn) {
 623                 DEBUG(10,("process_request: unknown request fn number %d\n",
 624                           (int)state->request->cmd ));
 625                 request_error(state);
 626         }
 627 }
 628
 629 static void wb_request_done(struct tevent_req *req)
 630 {
 631         struct winbindd_cli_state *state = tevent_req_callback_data(
 632                 req, struct winbindd_cli_state);
 633         NTSTATUS status;
 634
 635         state->response = talloc_zero(state, struct winbindd_response);
 636         if (state->response == NULL) {
 637                 remove_client(state);
 638                 return;
 639         }
 640         state->response->result = WINBINDD_PENDING;
 641         state->response->length = sizeof(struct winbindd_response);
 642
 643         status = state->recv_fn(req, state->response);
 644         TALLOC_FREE(req);
 645         if (!NT_STATUS_IS_OK(status)) {
 646                 DEBUG(10, ("returning %s\n", nt_errstr(status)));
 647                 request_error(state);
 648                 return;
 649         }
 650         request_ok(state);
 651 }
 652
 653 /*
 654  * This is the main event loop of winbind requests. It goes through a
 655  * state-machine of 3 read/write requests, 4 if you have extra data to send.
 656  *
 657  * An idle winbind client has a read request of 4 bytes outstanding,
 658  * finalizing function is request_len_recv, checking the length. request_recv
 659  * then processes the packet. The processing function then at some point has
 660  * to call request_finished which schedules sending the response.
 661  */
 662
 663 static void request_finished(struct winbindd_cli_state *state);
 664
 665 static void winbind_client_request_read(struct tevent_req *req);
 666 static void winbind_client_response_written(struct tevent_req *req);
 667
 668 static void request_finished(struct winbindd_cli_state *state)
 669 {
 670         struct tevent_req *req;
 671
 672         TALLOC_FREE(state->request);
 673
 674         req = wb_resp_write_send(state, winbind_event_context(),
 675                                  state->out_queue, state->sock,
 676                                  state->response);
 677         if (req == NULL) {
 678                 remove_client(state);
 679                 return;
 680         }
 681         tevent_req_set_callback(req, winbind_client_response_written, state);
 682 }
 683
 684 static void winbind_client_response_written(struct tevent_req *req)
 685 {
 686         struct winbindd_cli_state *state = tevent_req_callback_data(
 687                 req, struct winbindd_cli_state);
 688         ssize_t ret;
 689         int err;
 690
 691         ret = wb_resp_write_recv(req, &err);
 692         TALLOC_FREE(req);
 693         if (ret == -1) {
 694                 DEBUG(2, ("Could not write response to client: %s\n",
 695                           strerror(err)));
 696                 remove_client(state);
 697                 return;
 698         }
 699
 700         TALLOC_FREE(state->mem_ctx);
 701         state->response = NULL;
 702
 703         req = wb_req_read_send(state, winbind_event_context(), state->sock,
 704                                WINBINDD_MAX_EXTRA_DATA);
 705         if (req == NULL) {
 706                 remove_client(state);
 707                 return;
 708         }
 709         tevent_req_set_callback(req, winbind_client_request_read, state);
 710 }
 711
 712 void request_error(struct winbindd_cli_state *state)
 713 {
 714         SMB_ASSERT(state->response->result == WINBINDD_PENDING);
 715         state->response->result = WINBINDD_ERROR;
 716         request_finished(state);
 717 }
 718
 719 void request_ok(struct winbindd_cli_state *state)
 720 {
 721         SMB_ASSERT(state->response->result == WINBINDD_PENDING);
 722         state->response->result = WINBINDD_OK;
 723         request_finished(state);
 724 }
 725
 726 /* Process a new connection by adding it to the client connection list */
 727
 728 static void new_connection(int listen_sock, bool privileged)
 729 {
 730         struct sockaddr_un sunaddr;
 731         struct winbindd_cli_state *state;
 732         struct tevent_req *req;
 733         socklen_t len;
 734         int sock;
 735
 736         /* Accept connection */
 737
 738         len = sizeof(sunaddr);
 739
 740         do {
 741                 sock = accept(listen_sock, (struct sockaddr *)(void *)&sunaddr,
 742                               &len);
 743         } while (sock == -1 && errno == EINTR);
 744
 745         if (sock == -1)
 746                 return;
 747
 748         DEBUG(6,("accepted socket %d\n", sock));
 749
 750         /* Create new connection structure */
 751
 752         if ((state = TALLOC_ZERO_P(NULL, struct winbindd_cli_state)) == NULL) {
 753                 close(sock);
 754                 return;
 755         }
 756
 757         state->sock = sock;
 758
 759         state->out_queue = tevent_queue_create(state, "winbind client reply");
 760         if (state->out_queue == NULL) {
 761                 close(sock);
 762                 TALLOC_FREE(state);
 763                 return;
 764         }
 765
 766         state->last_access = time(NULL);
 767
 768         state->privileged = privileged;
 769
 770         req = wb_req_read_send(state, winbind_event_context(), state->sock,
 771                                WINBINDD_MAX_EXTRA_DATA);
 772         if (req == NULL) {
 773                 TALLOC_FREE(state);
 774                 close(sock);
 775                 return;
 776         }
 777         tevent_req_set_callback(req, winbind_client_request_read, state);
 778
 779         /* Add to connection list */
 780
 781         winbindd_add_client(state);
 782 }
 783
 784 static void winbind_client_request_read(struct tevent_req *req)
 785 {
 786         struct winbindd_cli_state *state = tevent_req_callback_data(
 787                 req, struct winbindd_cli_state);
 788         ssize_t ret;
 789         int err;
 790
 791         ret = wb_req_read_recv(req, state, &state->request, &err);
 792         TALLOC_FREE(req);
 793         if (ret == -1) {
 794                 DEBUG(2, ("Could not read client request: %s\n",
 795                           strerror(err)));
 796                 remove_client(state);
 797                 return;
 798         }
 799         process_request(state);
 800 }
 801
 802 /* Remove a client connection from client connection list */
 803
 804 static void remove_client(struct winbindd_cli_state *state)
 805 {
 806         char c = 0;
 807         int nwritten;
 808
 809         /* It's a dead client - hold a funeral */
 810
 811         if (state == NULL) {
 812                 return;
 813         }
 814
 815         /* tell client, we are closing ... */
 816         nwritten = write(state->sock, &c, sizeof(c));
 817         if (nwritten == -1) {
 818                 /*
 819                  * ignore EPIPE error here, because the other end might
 820                  * have already closed the socket.
 821                  */
 822                 if (errno != EPIPE) {
 823                         DEBUG(2, ("final write to client failed: %s\n",
 824                                 strerror(errno)));
 825                 }
 826         }
 827
 828         /* Close socket */
 829
 830         close(state->sock);
 831
 832         /* Free any getent state */
 833
 834         free_getent_state(state->getgrent_state);
 835
 836         TALLOC_FREE(state->mem_ctx);
 837
 838         /* Remove from list and free */
 839
 840         winbindd_remove_client(state);
 841         TALLOC_FREE(state);
 842 }
 843
 844 /* Shutdown client connection which has been idle for the longest time */
 845
 846 static bool remove_idle_client(void)
 847 {
 848         struct winbindd_cli_state *state, *remove_state = NULL;
 849         time_t last_access = 0;
 850         int nidle = 0;
 851
 852         for (state = winbindd_client_list(); state; state = state->next) {
 853                 if (state->response == NULL &&
 854                     !state->pwent_state && !state->getgrent_state) {
 855                         nidle++;
 856                         if (!last_access || state->last_access < last_access) {
 857                                 last_access = state->last_access;
 858                                 remove_state = state;
 859                         }
 860                 }
 861         }
 862
 863         if (remove_state) {
 864                 DEBUG(5,("Found %d idle client connections, shutting down sock %d, pid %u\n",
 865                         nidle, remove_state->sock, (unsigned int)remove_state->pid));
 866                 remove_client(remove_state);
 867                 return True;
 868         }
 869
 870         return False;
 871 }
 872
 873 struct winbindd_listen_state {
 874         bool privileged;
 875         int fd;
 876 };
 877
 878 static void winbindd_listen_fde_handler(struct tevent_context *ev,
 879                                         struct tevent_fd *fde,
 880                                         uint16_t flags,
 881                                         void *private_data)
 882 {
 883         struct winbindd_listen_state *s = talloc_get_type_abort(private_data,
 884                                           struct winbindd_listen_state);
 885
 886         while (winbindd_num_clients() >
 887                WINBINDD_MAX_SIMULTANEOUS_CLIENTS - 1) {
 888                 DEBUG(5,("winbindd: Exceeding %d client "
 889                          "connections, removing idle "
 890                          "connection.\n",
 891                          WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 892                 if (!remove_idle_client()) {
 893                         DEBUG(0,("winbindd: Exceeding %d "
 894                                  "client connections, no idle "
 895                                  "connection found\n",
 896                                  WINBINDD_MAX_SIMULTANEOUS_CLIENTS));
 897                         break;
 898                 }
 899         }
 900         new_connection(s->fd, s->privileged);
 901 }
 902
 903 static bool winbindd_setup_listeners(void)
 904 {
 905         struct winbindd_listen_state *pub_state = NULL;
 906         struct winbindd_listen_state *priv_state = NULL;
 907         struct tevent_fd *fde;
 908
 909         pub_state = talloc(winbind_event_context(),
 910                            struct winbindd_listen_state);
 911         if (!pub_state) {
 912                 goto failed;
 913         }
 914
 915         pub_state->privileged = false;
 916         pub_state->fd = open_winbindd_socket();
 917         if (pub_state->fd == -1) {
 918                 goto failed;
 919         }
 920
 921         fde = tevent_add_fd(winbind_event_context(), pub_state, pub_state->fd,
 922                             TEVENT_FD_READ, winbindd_listen_fde_handler,
 923                             pub_state);
 924         if (fde == NULL) {
 925                 close(pub_state->fd);
 926                 goto failed;
 927         }
 928         tevent_fd_set_auto_close(fde);
 929
 930         priv_state = talloc(winbind_event_context(),
 931                             struct winbindd_listen_state);
 932         if (!priv_state) {
 933                 goto failed;
 934         }
 935
 936         priv_state->privileged = true;
 937         priv_state->fd = open_winbindd_priv_socket();
 938         if (priv_state->fd == -1) {
 939                 goto failed;
 940         }
 941
 942         fde = tevent_add_fd(winbind_event_context(), priv_state,
 943                             priv_state->fd, TEVENT_FD_READ,
 944                             winbindd_listen_fde_handler, priv_state);
 945         if (fde == NULL) {
 946                 close(priv_state->fd);
 947                 goto failed;
 948         }
 949         tevent_fd_set_auto_close(fde);
 950
 951         return true;
 952 failed:
 953         TALLOC_FREE(pub_state);
 954         TALLOC_FREE(priv_state);
 955         return false;
 956 }
 957
 958 bool winbindd_use_idmap_cache(void)
 959 {
 960         return !opt_nocache;
 961 }
 962
 963 bool winbindd_use_cache(void)
 964 {
 965         return !opt_nocache;
 966 }
 967
 968 /* Main function */
 969
 970 int main(int argc, char **argv, char **envp)
 971 {
 972         static bool is_daemon = False;
 973         static bool Fork = True;
 974         static bool log_stdout = False;
 975         static bool no_process_group = False;
 976         enum {
 977                 OPT_DAEMON = 1000,
 978                 OPT_FORK,
 979                 OPT_NO_PROCESS_GROUP,
 980                 OPT_LOG_STDOUT
 981         };
 982         struct poptOption long_options[] = {
 983                 POPT_AUTOHELP
 984                 { "stdout", 'S', POPT_ARG_NONE, NULL, OPT_LOG_STDOUT, "Log to stdout" },
 985                 { "foreground", 'F', POPT_ARG_NONE, NULL, OPT_FORK, "Daemon in foreground mode" },
 986                 { "no-process-group", 0, POPT_ARG_NONE, NULL, OPT_NO_PROCESS_GROUP, "Don't create a new process group" },
 987                 { "daemon", 'D', POPT_ARG_NONE, NULL, OPT_DAEMON, "Become a daemon (default)" },
 988                 { "interactive", 'i', POPT_ARG_NONE, NULL, 'i', "Interactive mode" },
 989                 { "no-caching", 'n', POPT_ARG_NONE, NULL, 'n', "Disable caching" },
 990                 POPT_COMMON_SAMBA
 991                 POPT_TABLEEND
 992         };
 993         poptContext pc;
 994         int opt;
 995         TALLOC_CTX *frame = talloc_stackframe();
 996         struct tevent_timer *te;
 997
 998         /* glibc (?) likes to print "User defined signal 1" and exit if a
 999            SIGUSR[12] is received before a handler is installed */
1000
1001         CatchSignal(SIGUSR1, SIG_IGN);
1002         CatchSignal(SIGUSR2, SIG_IGN);
1003
1004         fault_setup((void (*)(void *))fault_quit );
1005         dump_core_setup("winbindd");
1006
1007         load_case_tables();
1008
1009         /* Initialise for running in non-root mode */
1010
1011         sec_init();
1012
1013         set_remote_machine_name("winbindd", False);
1014
1015         /* Set environment variable so we don't recursively call ourselves.
1016            This may also be useful interactively. */
1017
1018         if ( !winbind_off() ) {
1019                 DEBUG(0,("Failed to disable recusive winbindd calls.  Exiting.\n"));
1020                 exit(1);
1021         }
1022
1023         /* Initialise samba/rpc client stuff */
1024
1025         pc = poptGetContext("winbindd", argc, (const char **)argv, long_options, 0);
1026
1027         while ((opt = poptGetNextOpt(pc)) != -1) {
1028                 switch (opt) {
1029                         /* Don't become a daemon */
1030                 case OPT_DAEMON:
1031                         is_daemon = True;
1032                         break;
1033                 case 'i':
1034                         interactive = True;
1035                         log_stdout = True;
1036                         Fork = False;
1037                         break;
1038                 case OPT_FORK:
1039                         Fork = false;
1040                         break;
1041                 case OPT_NO_PROCESS_GROUP:
1042                         no_process_group = true;
1043                         break;
1044                 case OPT_LOG_STDOUT:
1045                         log_stdout = true;
1046                         break;
1047                 case 'n':
1048                         opt_nocache = true;
1049                         break;
1050                 default:
1051                         d_fprintf(stderr, "\nInvalid option %s: %s\n\n",
1052                                   poptBadOption(pc, 0), poptStrerror(opt));
1053                         poptPrintUsage(pc, stderr, 0);
1054                         exit(1);
1055                 }
1056         }
1057
1058         if (is_daemon && interactive) {
1059                 d_fprintf(stderr,"\nERROR: "
1060                           "Option -i|--interactive is not allowed together with -D|--daemon\n\n");
1061                 poptPrintUsage(pc, stderr, 0);
1062                 exit(1);
1063         }
1064
1065         if (log_stdout && Fork) {
1066                 d_fprintf(stderr, "\nERROR: "
1067                           "Can't log to stdout (-S) unless daemon is in foreground +(-F) or interactive (-i)\n\n");
1068                 poptPrintUsage(pc, stderr, 0);
1069                 exit(1);
1070         }
1071
1072         poptFreeContext(pc);
1073
1074         if (!override_logfile) {
1075                 char *lfile = NULL;
1076                 if (asprintf(&lfile,"%s/log.winbindd",
1077                                 get_dyn_LOGFILEBASE()) > 0) {
1078                         lp_set_logfile(lfile);
1079                         SAFE_FREE(lfile);
1080                 }
1081         }
1082         setup_logging("winbindd", log_stdout);
1083         reopen_logs();
1084
1085         DEBUG(0,("winbindd version %s started.\n", samba_version_string()));
1086         DEBUGADD(0,("%s\n", COPYRIGHT_STARTUP_MESSAGE));
1087
1088         if (!lp_load_initial_only(get_dyn_CONFIGFILE())) {
1089                 DEBUG(0, ("error opening config file\n"));
1090                 exit(1);
1091         }
1092
1093         /* Initialise messaging system */
1094
1095         if (winbind_messaging_context() == NULL) {
1096                 exit(1);
1097         }
1098
1099         if (!reload_services_file(NULL)) {
1100                 DEBUG(0, ("error opening config file\n"));
1101                 exit(1);
1102         }
1103
1104         if (!directory_exist(lp_lockdir())) {
1105                 mkdir(lp_lockdir(), 0755);
1106         }
1107
1108         /* Setup names. */
1109
1110         if (!init_names())
1111                 exit(1);
1112
1113         load_interfaces();
1114
1115         if (!secrets_init()) {
1116
1117                 DEBUG(0,("Could not initialize domain trust account secrets. Giving up\n"));
1118                 return False;
1119         }
1120
1121         /* Enable netbios namecache */
1122
1123         namecache_enable();
1124
1125         /* Unblock all signals we are interested in as they may have been
1126            blocked by the parent process. */
1127
1128         BlockSignals(False, SIGINT);
1129         BlockSignals(False, SIGQUIT);
1130         BlockSignals(False, SIGTERM);
1131         BlockSignals(False, SIGUSR1);
1132         BlockSignals(False, SIGUSR2);
1133         BlockSignals(False, SIGHUP);
1134         BlockSignals(False, SIGCHLD);
1135
1136         if (!interactive)
1137                 become_daemon(Fork, no_process_group);
1138
1139         pidfile_create("winbindd");
1140
1141 #if HAVE_SETPGID
1142         /*
1143          * If we're interactive we want to set our own process group for
1144          * signal management.
1145          */
1146         if (interactive && !no_process_group)
1147                 setpgid( (pid_t)0, (pid_t)0);
1148 #endif
1149
1150         TimeInit();
1151
1152         /* Don't use winbindd_reinit_after_fork here as
1153          * we're just starting up and haven't created any
1154          * winbindd-specific resources we must free yet. JRA.
1155          */
1156
1157         if (!NT_STATUS_IS_OK(reinit_after_fork(winbind_messaging_context(),
1158                                                winbind_event_context(),
1159                                                false))) {
1160                 DEBUG(0,("reinit_after_fork() failed\n"));
1161                 exit(1);
1162         }
1163
1164         /* Setup signal handlers */
1165
1166         if (!winbindd_setup_sig_term_handler(true))
1167                 exit(1);
1168         if (!winbindd_setup_sig_hup_handler(NULL))
1169                 exit(1);
1170         if (!winbindd_setup_sig_chld_handler())
1171                 exit(1);
1172         if (!winbindd_setup_sig_usr2_handler())
1173                 exit(1);
1174
1175         CatchSignal(SIGPIPE, SIG_IGN);                 /* Ignore sigpipe */
1176
1177         /*
1178          * Ensure all cache and idmap caches are consistent
1179          * and initialized before we startup.
1180          */
1181         if (!winbindd_cache_validate_and_initialize()) {
1182                 exit(1);
1183         }
1184
1185         /* get broadcast messages */
1186         claim_connection(NULL,"",FLAG_MSG_GENERAL|FLAG_MSG_DBWRAP);
1187
1188         /* React on 'smbcontrol winbindd reload-config' in the same way
1189            as to SIGHUP signal */
1190         messaging_register(winbind_messaging_context(), NULL,
1191                            MSG_SMB_CONF_UPDATED, msg_reload_services);
1192         messaging_register(winbind_messaging_context(), NULL,
1193                            MSG_SHUTDOWN, msg_shutdown);
1194
1195         /* Handle online/offline messages. */
1196         messaging_register(winbind_messaging_context(), NULL,
1197                            MSG_WINBIND_OFFLINE, winbind_msg_offline);
1198         messaging_register(winbind_messaging_context(), NULL,
1199                            MSG_WINBIND_ONLINE, winbind_msg_online);
1200         messaging_register(winbind_messaging_context(), NULL,
1201                            MSG_WINBIND_ONLINESTATUS, winbind_msg_onlinestatus);
1202
1203         messaging_register(winbind_messaging_context(), NULL,
1204                            MSG_DUMP_EVENT_LIST, winbind_msg_dump_event_list);
1205
1206         messaging_register(winbind_messaging_context(), NULL,
1207                            MSG_WINBIND_VALIDATE_CACHE,
1208                            winbind_msg_validate_cache);
1209
1210         messaging_register(winbind_messaging_context(), NULL,
1211                            MSG_WINBIND_DUMP_DOMAIN_LIST,
1212                            winbind_msg_dump_domain_list);
1213
1214         /* Register handler for MSG_DEBUG. */
1215         messaging_register(winbind_messaging_context(), NULL,
1216                            MSG_DEBUG,
1217                            winbind_msg_debug);
1218
1219         netsamlogon_cache_init(); /* Non-critical */
1220
1221         /* clear the cached list of trusted domains */
1222
1223         wcache_tdc_clear();
1224
1225         if (!init_domain_list()) {
1226                 DEBUG(0,("unable to initialize domain list\n"));
1227                 exit(1);
1228         }
1229
1230         init_idmap_child();
1231         init_locator_child();
1232
1233         smb_nscd_flush_user_cache();
1234         smb_nscd_flush_group_cache();
1235
1236         /* setup listen sockets */
1237
1238         if (!winbindd_setup_listeners()) {
1239                 DEBUG(0,("winbindd_setup_listeners() failed\n"));
1240                 exit(1);
1241         }
1242
1243         te = tevent_add_timer(winbind_event_context(), NULL, timeval_zero(),
1244                               rescan_trusted_domains, NULL);
1245         if (te == NULL) {
1246                 DEBUG(0, ("Could not trigger rescan_trusted_domains()\n"));
1247                 exit(1);
1248         }
1249
1250         TALLOC_FREE(frame);
1251         /* Loop waiting for requests */
1252         while (1) {
1253                 frame = talloc_stackframe();
1254
1255                 if (tevent_loop_once(winbind_event_context()) == -1) {
1256                         DEBUG(1, ("tevent_loop_once() failed: %s\n",
1257                                   strerror(errno)));
1258                         return 1;
1259                 }
1260
1261                 TALLOC_FREE(frame);
1262         }
1263
1264         return 0;
1265 }