source3/winbindd/idmap.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    ID Mapping
   4    Copyright (C) Tim Potter 2000
   5    Copyright (C) Jim McDonough <jmcd@us.ibm.com>        2003
   6    Copyright (C) Simo Sorce 2003-2007
   7    Copyright (C) Jeremy Allison 2006
   8    Copyright (C) Michael Adam 2010
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "winbindd.h"
  26 #include "idmap.h"
  27 #include "lib/util_sid_passdb.h"
  28 #include "passdb.h"
  29
  30 #undef DBGC_CLASS
  31 #define DBGC_CLASS DBGC_IDMAP
  32
  33 static_decl_idmap;
  34
  35 /**
  36  * Pointer to the backend methods. Modules register themselves here via
  37  * smb_register_idmap.
  38  */
  39
  40 struct idmap_backend {
  41         const char *name;
  42         struct idmap_methods *methods;
  43         struct idmap_backend *prev, *next;
  44 };
  45 static struct idmap_backend *backends = NULL;
  46
  47 /**
  48  * Default idmap domain configured via "idmap backend".
  49  */
  50 static struct idmap_domain *default_idmap_domain;
  51
  52 /**
  53  * Passdb idmap domain, not configurable. winbind must always give passdb a
  54  * chance to map ids.
  55  */
  56 static struct idmap_domain *passdb_idmap_domain;
  57
  58 /**
  59  * List of specially configured idmap domains. This list is filled on demand
  60  * in the winbind idmap child when the parent winbind figures out via the
  61  * special range parameter or via the domain SID that a special "idmap config
  62  * domain" configuration is present.
  63  */
  64 static struct idmap_domain **idmap_domains = NULL;
  65 static int num_domains = 0;
  66
  67 static struct idmap_domain *idmap_init_named_domain(TALLOC_CTX *mem_ctx,
  68                                                     const char *domname);
  69 static struct idmap_domain *idmap_init_domain(TALLOC_CTX *mem_ctx,
  70                                               const char *domainname,
  71                                               const char *modulename,
  72                                               bool check_range);
  73 static bool idmap_found_domain_backend(
  74         const char *string, regmatch_t matches[], void *private_data);
  75
  76 static bool idmap_init(void)
  77 {
  78         static bool initialized;
  79         int ret;
  80
  81         if (initialized) {
  82                 return true;
  83         }
  84
  85         DEBUG(10, ("idmap_init(): calling static_init_idmap\n"));
  86
  87         static_init_idmap;
  88
  89         initialized = true;
  90
  91         if (!pdb_is_responsible_for_everything_else()) {
  92                 default_idmap_domain = idmap_init_named_domain(NULL, "*");
  93                 if (default_idmap_domain == NULL) {
  94                         return false;
  95                 }
  96         }
  97
  98         passdb_idmap_domain = idmap_init_domain(
  99                 NULL, get_global_sam_name(), "passdb", false);
 100         if (passdb_idmap_domain == NULL) {
 101                 TALLOC_FREE(default_idmap_domain);
 102                 return false;
 103         }
 104
 105         idmap_domains = talloc_array(NULL, struct idmap_domain *, 0);
 106         if (idmap_domains == NULL) {
 107                 TALLOC_FREE(passdb_idmap_domain);
 108                 TALLOC_FREE(default_idmap_domain);
 109                 return false;
 110         }
 111
 112         ret = lp_wi_scan_global_parametrics(
 113                 "idmapconfig\\(.*\\):backend", 2,
 114                 idmap_found_domain_backend, NULL);
 115         if (ret != 0) {
 116                 DBG_WARNING("wi_scan_global_parametrics returned %d\n", ret);
 117                 return false;
 118         }
 119
 120         return true;
 121 }
 122
 123 static bool idmap_found_domain_backend(
 124         const char *string, regmatch_t matches[], void *private_data)
 125 {
 126         if (matches[1].rm_so == -1) {
 127                 DBG_WARNING("Found match, but no name??\n");
 128                 return false;
 129         }
 130
 131         {
 132                 struct idmap_domain *dom, **tmp;
 133                 regoff_t len = matches[1].rm_eo - matches[1].rm_so;
 134                 char domname[len+1];
 135
 136                 memcpy(domname, string + matches[1].rm_so, len);
 137                 domname[len] = '\0';
 138
 139                 DBG_DEBUG("Found idmap domain \"%s\"\n", domname);
 140
 141                 if (strcmp(domname, "*") == 0) {
 142                         return false;
 143                 }
 144
 145                 dom = idmap_init_named_domain(idmap_domains, domname);
 146                 if (dom == NULL) {
 147                         DBG_NOTICE("Could not init idmap domain %s\n",
 148                                    domname);
 149                         return false;
 150                 }
 151
 152                 tmp = talloc_realloc(idmap_domains, idmap_domains,
 153                                      struct idmap_domain *, num_domains + 1);
 154                 if (tmp == NULL) {
 155                         DBG_WARNING("talloc_realloc failed\n");
 156                         TALLOC_FREE(dom);
 157                         return false;
 158                 }
 159                 idmap_domains = tmp;
 160                 idmap_domains[num_domains] = dom;
 161                 num_domains += 1;
 162         }
 163
 164         return false;
 165 }
 166
 167 static struct idmap_methods *get_methods(const char *name)
 168 {
 169         struct idmap_backend *b;
 170
 171         for (b = backends; b; b = b->next) {
 172                 if (strequal(b->name, name)) {
 173                         return b->methods;
 174                 }
 175         }
 176
 177         return NULL;
 178 }
 179
 180 bool idmap_is_offline(void)
 181 {
 182         return ( lp_winbind_offline_logon() &&
 183              get_global_winbindd_state_offline() );
 184 }
 185
 186 bool idmap_is_online(void)
 187 {
 188         return !idmap_is_offline();
 189 }
 190
 191 /**********************************************************************
 192  Allow a module to register itself as a method.
 193 **********************************************************************/
 194
 195 NTSTATUS smb_register_idmap(int version, const char *name,
 196                             struct idmap_methods *methods)
 197 {
 198         struct idmap_backend *entry;
 199
 200         if ((version != SMB_IDMAP_INTERFACE_VERSION)) {
 201                 DEBUG(0, ("Failed to register idmap module.\n"
 202                           "The module was compiled against "
 203                           "SMB_IDMAP_INTERFACE_VERSION %d,\n"
 204                           "current SMB_IDMAP_INTERFACE_VERSION is %d.\n"
 205                           "Please recompile against the current version "
 206                           "of samba!\n",
 207                           version, SMB_IDMAP_INTERFACE_VERSION));
 208                 return NT_STATUS_OBJECT_TYPE_MISMATCH;
 209         }
 210
 211         if (!name || !name[0] || !methods) {
 212                 DEBUG(0,("Called with NULL pointer or empty name!\n"));
 213                 return NT_STATUS_INVALID_PARAMETER;
 214         }
 215
 216         for (entry = backends; entry != NULL; entry = entry->next) {
 217                 if (strequal(entry->name, name)) {
 218                         DEBUG(5,("Idmap module %s already registered!\n",
 219                                  name));
 220                         return NT_STATUS_OBJECT_NAME_COLLISION;
 221                 }
 222         }
 223
 224         entry = talloc(NULL, struct idmap_backend);
 225         if ( ! entry) {
 226                 DEBUG(0,("Out of memory!\n"));
 227                 TALLOC_FREE(entry);
 228                 return NT_STATUS_NO_MEMORY;
 229         }
 230         entry->name = talloc_strdup(entry, name);
 231         if ( ! entry->name) {
 232                 DEBUG(0,("Out of memory!\n"));
 233                 TALLOC_FREE(entry);
 234                 return NT_STATUS_NO_MEMORY;
 235         }
 236         entry->methods = methods;
 237
 238         DLIST_ADD(backends, entry);
 239         DEBUG(5, ("Successfully added idmap backend '%s'\n", name));
 240         return NT_STATUS_OK;
 241 }
 242
 243 /**
 244  * Initialize a domain structure
 245  * @param[in] mem_ctx           memory context for the result
 246  * @param[in] domainname        which domain is this for
 247  * @param[in] modulename        which backend module
 248  * @param[in] check_range       whether range checking should be done
 249  * @result The initialized structure
 250  */
 251 static struct idmap_domain *idmap_init_domain(TALLOC_CTX *mem_ctx,
 252                                               const char *domainname,
 253                                               const char *modulename,
 254                                               bool check_range)
 255 {
 256         struct idmap_domain *result;
 257         NTSTATUS status;
 258         char *config_option = NULL;
 259         const char *range;
 260         unsigned low_id = 0;
 261         unsigned high_id = 0;
 262
 263         result = talloc_zero(mem_ctx, struct idmap_domain);
 264         if (result == NULL) {
 265                 DEBUG(0, ("talloc failed\n"));
 266                 return NULL;
 267         }
 268
 269         result->name = talloc_strdup(result, domainname);
 270         if (result->name == NULL) {
 271                 DEBUG(0, ("talloc failed\n"));
 272                 goto fail;
 273         }
 274
 275         /*
 276          * Check whether the requested backend module exists and
 277          * load the methods.
 278          */
 279
 280         result->methods = get_methods(modulename);
 281         if (result->methods == NULL) {
 282                 DEBUG(3, ("idmap backend %s not found\n", modulename));
 283
 284                 status = smb_probe_module("idmap", modulename);
 285                 if (!NT_STATUS_IS_OK(status)) {
 286                         DEBUG(3, ("Could not probe idmap module %s\n",
 287                                   modulename));
 288                         goto fail;
 289                 }
 290
 291                 result->methods = get_methods(modulename);
 292         }
 293         if (result->methods == NULL) {
 294                 DEBUG(1, ("idmap backend %s not found\n", modulename));
 295                 goto fail;
 296         }
 297
 298         /*
 299          * load ranges and read only information from the config
 300          */
 301
 302         config_option = talloc_asprintf(result, "idmap config %s",
 303                                         result->name);
 304         if (config_option == NULL) {
 305                 DEBUG(0, ("Out of memory!\n"));
 306                 goto fail;
 307         }
 308
 309         result->read_only = lp_parm_bool(-1, config_option, "read only", false);
 310         range = lp_parm_const_string(-1, config_option, "range", NULL);
 311
 312         talloc_free(config_option);
 313
 314         if (range == NULL) {
 315                 if (check_range) {
 316                         DEBUG(1, ("idmap range not specified for domain %s\n",
 317                                   result->name));
 318                         goto fail;
 319                 }
 320         } else if (sscanf(range, "%u - %u", &low_id, &high_id) != 2)
 321         {
 322                 DEBUG(1, ("invalid range '%s' specified for domain "
 323                           "'%s'\n", range, result->name));
 324                 if (check_range) {
 325                         goto fail;
 326                 }
 327         } else if (low_id > high_id) {
 328                 DEBUG(1, ("Error: invalid idmap range detected: %u - %u\n",
 329                           low_id, high_id));
 330                 if (check_range) {
 331                         goto fail;
 332                 }
 333         }
 334
 335         result->low_id = low_id;
 336         result->high_id = high_id;
 337
 338         status = result->methods->init(result);
 339         if (!NT_STATUS_IS_OK(status)) {
 340                 DEBUG(1, ("idmap initialization returned %s\n",
 341                           nt_errstr(status)));
 342                 goto fail;
 343         }
 344
 345         return result;
 346
 347 fail:
 348         TALLOC_FREE(result);
 349         return NULL;
 350 }
 351
 352 /**
 353  * Initialize a named domain structure
 354  * @param[in] mem_ctx           memory context for the result
 355  * @param[in] domname           the domain name
 356  * @result The default domain structure
 357  *
 358  * This routine looks at the "idmap config <domname>" parameters to figure out
 359  * the configuration.
 360  */
 361
 362 static struct idmap_domain *idmap_init_named_domain(TALLOC_CTX *mem_ctx,
 363                                                     const char *domname)
 364 {
 365         struct idmap_domain *result = NULL;
 366         char *config_option;
 367         const char *backend;
 368         bool ok;
 369
 370         ok = idmap_init();
 371         if (!ok) {
 372                 return NULL;
 373         }
 374
 375         config_option = talloc_asprintf(talloc_tos(), "idmap config %s",
 376                                         domname);
 377         if (config_option == NULL) {
 378                 DEBUG(0, ("talloc failed\n"));
 379                 goto fail;
 380         }
 381
 382         backend = lp_parm_const_string(-1, config_option, "backend", NULL);
 383         if (backend == NULL) {
 384                 DEBUG(10, ("no idmap backend configured for domain '%s'\n",
 385                            domname));
 386                 goto fail;
 387         }
 388
 389         result = idmap_init_domain(mem_ctx, domname, backend, true);
 390         if (result == NULL) {
 391                 goto fail;
 392         }
 393
 394         TALLOC_FREE(config_option);
 395         return result;
 396
 397 fail:
 398         TALLOC_FREE(config_option);
 399         TALLOC_FREE(result);
 400         return NULL;
 401 }
 402
 403 /**
 404  * Find a domain struct according to a domain name
 405  * @param[in] domname           Domain name to get the config for
 406  * @result The default domain structure that fits
 407  *
 408  * This is the central routine in the winbindd-idmap child to pick the correct
 409  * domain for looking up IDs. If domname is NULL or empty, we use the default
 410  * domain. If it contains something, we try to use idmap_init_named_domain()
 411  * to fetch the correct backend.
 412  *
 413  * The choice about "domname" is being made by the winbind parent, look at the
 414  * "have_idmap_config" of "struct winbindd_domain" which is set in
 415  * add_trusted_domain.
 416  */
 417
 418 static struct idmap_domain *idmap_find_domain(const char *domname)
 419 {
 420         bool ok;
 421         int i;
 422
 423         DEBUG(10, ("idmap_find_domain called for domain '%s'\n",
 424                    domname?domname:"NULL"));
 425
 426         ok = idmap_init();
 427         if (!ok) {
 428                 return NULL;
 429         }
 430
 431         if ((domname == NULL) || (domname[0] == '\0')) {
 432                 return default_idmap_domain;
 433         }
 434
 435         for (i=0; i<num_domains; i++) {
 436                 if (strequal(idmap_domains[i]->name, domname)) {
 437                         return idmap_domains[i];
 438                 }
 439         }
 440
 441         return default_idmap_domain;
 442 }
 443
 444 struct idmap_domain *idmap_find_domain_with_sid(const char *domname,
 445                                                 const struct dom_sid *sid)
 446 {
 447         bool ok;
 448
 449         ok = idmap_init();
 450         if (!ok) {
 451                 return NULL;
 452         }
 453
 454         if (sid_check_is_for_passdb(sid)) {
 455                 return passdb_idmap_domain;
 456         }
 457
 458         return idmap_find_domain(domname);
 459 }
 460
 461 void idmap_close(void)
 462 {
 463         TALLOC_FREE(default_idmap_domain);
 464         TALLOC_FREE(passdb_idmap_domain);
 465         TALLOC_FREE(idmap_domains);
 466         num_domains = 0;
 467 }
 468
 469 /**************************************************************************
 470  idmap allocator interface functions
 471 **************************************************************************/
 472
 473 static NTSTATUS idmap_allocate_unixid(struct unixid *id)
 474 {
 475         struct idmap_domain *dom;
 476         NTSTATUS ret;
 477
 478         dom = idmap_find_domain(NULL);
 479
 480         if (dom == NULL) {
 481                 return NT_STATUS_UNSUCCESSFUL;
 482         }
 483
 484         if (dom->methods->allocate_id == NULL) {
 485                 return NT_STATUS_NOT_IMPLEMENTED;
 486         }
 487
 488         ret = dom->methods->allocate_id(dom, id);
 489
 490         return ret;
 491 }
 492
 493
 494 NTSTATUS idmap_allocate_uid(struct unixid *id)
 495 {
 496         id->type = ID_TYPE_UID;
 497         return idmap_allocate_unixid(id);
 498 }
 499
 500 NTSTATUS idmap_allocate_gid(struct unixid *id)
 501 {
 502         id->type = ID_TYPE_GID;
 503         return idmap_allocate_unixid(id);
 504 }
 505
 506 NTSTATUS idmap_backends_unixid_to_sid(struct id_map *id)
 507 {
 508         struct idmap_domain *dom;
 509         struct id_map *maps[2];
 510         bool ok;
 511         int i;
 512
 513         ok = idmap_init();
 514         if (!ok) {
 515                 return NT_STATUS_NONE_MAPPED;
 516         }
 517
 518         DEBUG(10, ("idmap_backend_unixid_to_sid: xid = %d (type %d)\n",
 519                    id->xid.id, id->xid.type));
 520
 521         maps[0] = id;
 522         maps[1] = NULL;
 523
 524         /*
 525          * Always give passdb a chance first
 526          */
 527
 528         dom = passdb_idmap_domain;
 529         if ((dom != NULL)
 530             && NT_STATUS_IS_OK(dom->methods->unixids_to_sids(dom, maps))
 531             && id->status == ID_MAPPED) {
 532                 return NT_STATUS_OK;
 533         }
 534
 535         dom = default_idmap_domain;
 536
 537         for (i=0; i<num_domains; i++) {
 538                 if ((id->xid.id >= idmap_domains[i]->low_id) &&
 539                     (id->xid.id <= idmap_domains[i]->high_id)) {
 540                         dom = idmap_domains[i];
 541                         break;
 542                 }
 543         }
 544
 545         if (dom == NULL) {
 546                 return NT_STATUS_NONE_MAPPED;
 547         }
 548
 549         return dom->methods->unixids_to_sids(dom, maps);
 550 }