source3/winbindd/idmap_tdb_common.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    common functions for TDB based idmapping backends
   5
   6    Copyright (C) Christian Ambach 2012
   7
   8    These functions were initially copied over from idmap_tdb.c and idmap_tdb2.c
   9    which are:
  10
  11    Copyright (C) Tim Potter 2000
  12    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
  13    Copyright (C) Jeremy Allison 2006
  14    Copyright (C) Simo Sorce 2003-2006
  15    Copyright (C) Michael Adam 2009-2010
  16    Copyright (C) Andrew Tridgell 2007
  17
  18    This program is free software; you can redistribute it and/or modify
  19    it under the terms of the GNU General Public License as published by
  20    the Free Software Foundation; either version 2 of the License, or
  21    (at your option) any later version.
  22
  23    This program is distributed in the hope that it will be useful,
  24    but WITHOUT ANY WARRANTY; without even the implied warranty of
  25    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26    GNU General Public License for more details.
  27
  28    You should have received a copy of the GNU General Public License
  29    along with this program; if not, write to the Free Software
  30    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  31 */
  32
  33 #include "includes.h"
  34 #include "idmap_tdb_common.h"
  35 #include "dbwrap/dbwrap.h"
  36 #include "util_tdb.h"
  37 #include "idmap_rw.h"
  38 #include "../libcli/security/dom_sid.h"
  39
  40 #undef DBGC_CLASS
  41 #define DBGC_CLASS DBGC_IDMAP
  42
  43 struct idmap_tdb_common_allocate_id_context {
  44         const char *hwmkey;
  45         const char *hwmtype;
  46         uint32_t high_hwm;
  47         uint32_t hwm;
  48 };
  49
  50 static NTSTATUS idmap_tdb_common_allocate_id_action(struct db_context *db,
  51                                                     void *private_data)
  52 {
  53         NTSTATUS ret;
  54         struct idmap_tdb_common_allocate_id_context *state = private_data;
  55         uint32_t hwm;
  56
  57         ret = dbwrap_fetch_uint32_bystring(db, state->hwmkey, &hwm);
  58         if (!NT_STATUS_IS_OK(ret)) {
  59                 ret = NT_STATUS_INTERNAL_DB_ERROR;
  60                 goto done;
  61         }
  62
  63         /* check it is in the range */
  64         if (hwm > state->high_hwm) {
  65                 DEBUG(1, ("Fatal Error: %s range full!! (max: %lu)\n",
  66                           state->hwmtype, (unsigned long)state->high_hwm));
  67                 ret = NT_STATUS_UNSUCCESSFUL;
  68                 goto done;
  69         }
  70
  71         /* fetch a new id and increment it */
  72         ret = dbwrap_change_uint32_atomic_bystring(db, state->hwmkey, &hwm, 1);
  73         if (!NT_STATUS_IS_OK(ret)) {
  74                 DEBUG(1, ("Fatal error while fetching a new %s value\n!",
  75                           state->hwmtype));
  76                 goto done;
  77         }
  78
  79         /* recheck it is in the range */
  80         if (hwm > state->high_hwm) {
  81                 DEBUG(1, ("Fatal Error: %s range full!! (max: %lu)\n",
  82                           state->hwmtype, (unsigned long)state->high_hwm));
  83                 ret = NT_STATUS_UNSUCCESSFUL;
  84                 goto done;
  85         }
  86
  87         ret = NT_STATUS_OK;
  88         state->hwm = hwm;
  89
  90       done:
  91         return ret;
  92 }
  93
  94 static NTSTATUS idmap_tdb_common_allocate_id(struct idmap_domain *dom,
  95                                              struct unixid *xid)
  96 {
  97         const char *hwmkey;
  98         const char *hwmtype;
  99         uint32_t hwm = 0;
 100         NTSTATUS status;
 101         struct idmap_tdb_common_allocate_id_context state;
 102         struct idmap_tdb_common_context *ctx;
 103
 104         ctx =
 105             talloc_get_type_abort(dom->private_data,
 106                                   struct idmap_tdb_common_context);
 107
 108         /* Get current high water mark */
 109         switch (xid->type) {
 110
 111         case ID_TYPE_UID:
 112                 hwmkey = ctx->hwmkey_uid;
 113                 hwmtype = "UID";
 114                 break;
 115
 116         case ID_TYPE_GID:
 117                 hwmkey = ctx->hwmkey_gid;
 118                 hwmtype = "GID";
 119                 break;
 120
 121         default:
 122                 DEBUG(2, ("Invalid ID type (0x%x)\n", xid->type));
 123                 return NT_STATUS_INVALID_PARAMETER;
 124         }
 125
 126         state.hwm = hwm;
 127         state.high_hwm = ctx->max_id;
 128         state.hwmtype = hwmtype;
 129         state.hwmkey = hwmkey;
 130
 131         status = dbwrap_trans_do(ctx->db, idmap_tdb_common_allocate_id_action,
 132                                  &state);
 133
 134         if (NT_STATUS_IS_OK(status)) {
 135                 xid->id = state.hwm;
 136                 DEBUG(10, ("New %s = %d\n", hwmtype, state.hwm));
 137         } else {
 138                 DEBUG(1, ("Error allocating a new %s\n", hwmtype));
 139         }
 140
 141         return status;
 142 }
 143
 144 /**
 145  * Allocate a new unix-ID.
 146  * For now this is for the default idmap domain only.
 147  * Should be extended later on.
 148  */
 149 NTSTATUS idmap_tdb_common_get_new_id(struct idmap_domain * dom,
 150                                      struct unixid * id)
 151 {
 152         NTSTATUS ret;
 153
 154         if (!strequal(dom->name, "*")) {
 155                 DEBUG(3, ("idmap_tdb_common_get_new_id: "
 156                           "Refusing allocation of a new unixid for domain'%s'. "
 157                           "Currently only supported for the default "
 158                           "domain \"*\".\n", dom->name));
 159                 return NT_STATUS_NOT_IMPLEMENTED;
 160         }
 161
 162         ret = idmap_tdb_common_allocate_id(dom, id);
 163
 164         return ret;
 165 }
 166
 167 /**
 168  * store a mapping in the database.
 169  */
 170
 171 struct idmap_tdb_common_set_mapping_context {
 172         const char *ksidstr;
 173         const char *kidstr;
 174 };
 175
 176 static NTSTATUS idmap_tdb_common_set_mapping_action(struct db_context *db,
 177                                                     void *private_data)
 178 {
 179         TDB_DATA data;
 180         NTSTATUS ret;
 181         struct idmap_tdb_common_set_mapping_context *state = private_data;
 182         TALLOC_CTX *tmp_ctx = talloc_stackframe();
 183
 184         DEBUG(10, ("Storing %s <-> %s map\n", state->ksidstr, state->kidstr));
 185
 186         /* check whether sid mapping is already present in db */
 187         ret = dbwrap_fetch_bystring(db, tmp_ctx, state->ksidstr, &data);
 188         if (NT_STATUS_IS_OK(ret)) {
 189                 ret = NT_STATUS_OBJECT_NAME_COLLISION;
 190                 goto done;
 191         }
 192
 193         ret = dbwrap_store_bystring(db, state->ksidstr,
 194                                     string_term_tdb_data(state->kidstr),
 195                                     TDB_INSERT);
 196         if (!NT_STATUS_IS_OK(ret)) {
 197                 DEBUG(0, ("Error storing SID -> ID: %s\n", nt_errstr(ret)));
 198                 goto done;
 199         }
 200
 201         ret = dbwrap_store_bystring(db, state->kidstr,
 202                                     string_term_tdb_data(state->ksidstr),
 203                                     TDB_INSERT);
 204         if (!NT_STATUS_IS_OK(ret)) {
 205                 DEBUG(0, ("Error storing ID -> SID: %s\n", nt_errstr(ret)));
 206                 /* try to remove the previous stored SID -> ID map */
 207                 dbwrap_delete_bystring(db, state->ksidstr);
 208                 goto done;
 209         }
 210
 211         DEBUG(10, ("Stored %s <-> %s\n", state->ksidstr, state->kidstr));
 212
 213       done:
 214         talloc_free(tmp_ctx);
 215         return ret;
 216 }
 217
 218 NTSTATUS idmap_tdb_common_set_mapping(struct idmap_domain * dom,
 219                                       const struct id_map * map)
 220 {
 221         struct idmap_tdb_common_context *ctx;
 222         struct idmap_tdb_common_set_mapping_context state;
 223         NTSTATUS ret;
 224         char *ksidstr, *kidstr;
 225
 226         if (!map || !map->sid) {
 227                 return NT_STATUS_INVALID_PARAMETER;
 228         }
 229
 230         ksidstr = kidstr = NULL;
 231
 232         /* TODO: should we filter a set_mapping using low/high filters ? */
 233
 234         ctx =
 235             talloc_get_type_abort(dom->private_data,
 236                                   struct idmap_tdb_common_context);
 237
 238         switch (map->xid.type) {
 239
 240         case ID_TYPE_UID:
 241                 kidstr =
 242                     talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
 243                 break;
 244
 245         case ID_TYPE_GID:
 246                 kidstr =
 247                     talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
 248                 break;
 249
 250         default:
 251                 DEBUG(2, ("INVALID unix ID type: 0x%02x\n", map->xid.type));
 252                 return NT_STATUS_INVALID_PARAMETER;
 253         }
 254
 255         if (kidstr == NULL) {
 256                 DEBUG(0, ("ERROR: Out of memory!\n"));
 257                 ret = NT_STATUS_NO_MEMORY;
 258                 goto done;
 259         }
 260
 261         ksidstr = sid_string_talloc(ctx, map->sid);
 262         if (ksidstr == NULL) {
 263                 DEBUG(0, ("Out of memory!\n"));
 264                 ret = NT_STATUS_NO_MEMORY;
 265                 goto done;
 266         }
 267
 268         state.ksidstr = ksidstr;
 269         state.kidstr = kidstr;
 270
 271         ret = dbwrap_trans_do(ctx->db, idmap_tdb_common_set_mapping_action,
 272                               &state);
 273
 274       done:
 275         talloc_free(ksidstr);
 276         talloc_free(kidstr);
 277         return ret;
 278 }
 279
 280 /*
 281  * Create a new mapping for an unmapped SID, also allocating a new ID.
 282  * This should be run inside a transaction.
 283  *
 284  * TODO:
 285  *  Properly integrate this with multi domain idmap config:
 286  *  Currently, the allocator is default-config only.
 287  */
 288 NTSTATUS idmap_tdb_common_new_mapping(struct idmap_domain * dom,
 289                                       struct id_map * map)
 290 {
 291         NTSTATUS ret;
 292         struct idmap_tdb_common_context *ctx;
 293
 294         ctx =
 295             talloc_get_type_abort(dom->private_data,
 296                                   struct idmap_tdb_common_context);
 297
 298         ret = idmap_rw_new_mapping(dom, ctx->rw_ops, map);
 299
 300         return ret;
 301 }
 302
 303 /*
 304   lookup a set of unix ids
 305 */
 306 NTSTATUS idmap_tdb_common_unixids_to_sids(struct idmap_domain * dom,
 307                                           struct id_map ** ids)
 308 {
 309         NTSTATUS ret;
 310         size_t i, num_mapped = 0;
 311         struct idmap_tdb_common_context *ctx;
 312
 313         NTSTATUS(*unixid_to_sid_fn) (struct idmap_domain * dom,
 314                                      struct id_map * map);
 315         ctx =
 316             talloc_get_type_abort(dom->private_data,
 317                                   struct idmap_tdb_common_context);
 318
 319         if (ctx->unixid_to_sid_fn == NULL) {
 320                 unixid_to_sid_fn = idmap_tdb_common_unixid_to_sid;
 321         } else {
 322                 unixid_to_sid_fn = ctx->unixid_to_sid_fn;
 323         }
 324
 325         /* initialize the status to avoid surprise */
 326         for (i = 0; ids[i]; i++) {
 327                 ids[i]->status = ID_UNKNOWN;
 328         }
 329
 330         for (i = 0; ids[i]; i++) {
 331                 ret = unixid_to_sid_fn(dom, ids[i]);
 332                 if (!NT_STATUS_IS_OK(ret)) {
 333
 334                         /* if it is just a failed mapping continue */
 335                         if (NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) {
 336
 337                                 /* make sure it is marked as unmapped */
 338                                 ids[i]->status = ID_UNMAPPED;
 339                                 continue;
 340                         }
 341
 342                         /* some fatal error occurred, return immediately */
 343                         goto done;
 344                 }
 345
 346                 /* all ok, id is mapped */
 347                 ids[i]->status = ID_MAPPED;
 348                 num_mapped += 1;
 349         }
 350
 351         ret = NT_STATUS_OK;
 352
 353 done:
 354
 355         if (NT_STATUS_IS_OK(ret)) {
 356                 if (i == 0 || num_mapped == 0) {
 357                         ret = NT_STATUS_NONE_MAPPED;
 358                 } else if (num_mapped < i) {
 359                         ret = STATUS_SOME_UNMAPPED;
 360                 } else {
 361                         ret = NT_STATUS_OK;
 362                 }
 363         }
 364
 365         return ret;
 366 }
 367
 368 /*
 369   default single id to sid lookup function
 370 */
 371 NTSTATUS idmap_tdb_common_unixid_to_sid(struct idmap_domain * dom,
 372                                         struct id_map * map)
 373 {
 374         NTSTATUS ret;
 375         TDB_DATA data;
 376         char *keystr;
 377         struct idmap_tdb_common_context *ctx;
 378
 379         if (!dom || !map) {
 380                 return NT_STATUS_INVALID_PARAMETER;
 381         }
 382
 383         ctx =
 384             talloc_get_type_abort(dom->private_data,
 385                                   struct idmap_tdb_common_context);
 386
 387         /* apply filters before checking */
 388         if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
 389                 DEBUG(5,
 390                       ("Requested id (%u) out of range (%u - %u). Filtered!\n",
 391                        map->xid.id, dom->low_id, dom->high_id));
 392                 return NT_STATUS_NONE_MAPPED;
 393         }
 394
 395         switch (map->xid.type) {
 396
 397         case ID_TYPE_UID:
 398                 keystr =
 399                     talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
 400                 break;
 401
 402         case ID_TYPE_GID:
 403                 keystr =
 404                     talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
 405                 break;
 406
 407         default:
 408                 DEBUG(2, ("INVALID unix ID type: 0x%02x\n", map->xid.type));
 409                 return NT_STATUS_INVALID_PARAMETER;
 410         }
 411
 412         if (keystr == NULL) {
 413                 DEBUG(0, ("Out of memory!\n"));
 414                 ret = NT_STATUS_NO_MEMORY;
 415                 goto done;
 416         }
 417
 418         DEBUG(10, ("Fetching record %s\n", keystr));
 419
 420         /* Check if the mapping exists */
 421         ret = dbwrap_fetch_bystring(ctx->db, keystr, keystr, &data);
 422
 423         if (!NT_STATUS_IS_OK(ret)) {
 424                 DEBUG(10, ("Record %s not found\n", keystr));
 425                 ret = NT_STATUS_NONE_MAPPED;
 426                 goto done;
 427         }
 428
 429         if ((data.dsize == 0) || (data.dptr[data.dsize-1] != '\0')) {
 430                 DBG_DEBUG("Invalid record length %zu\n", data.dsize);
 431                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 432                 goto done;
 433         }
 434
 435         if (!string_to_sid(map->sid, (const char *)data.dptr)) {
 436                 DEBUG(10, ("INVALID SID (%s) in record %s\n",
 437                            (const char *)data.dptr, keystr));
 438                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 439                 goto done;
 440         }
 441
 442         DEBUG(10, ("Found record %s -> %s\n", keystr, (const char *)data.dptr));
 443         ret = NT_STATUS_OK;
 444
 445       done:
 446         talloc_free(keystr);
 447         return ret;
 448 }
 449
 450 /**********************************
 451  Single sid to id lookup function.
 452 **********************************/
 453
 454 NTSTATUS idmap_tdb_common_sid_to_unixid(struct idmap_domain * dom,
 455                                         struct id_map * map)
 456 {
 457         NTSTATUS ret;
 458         TDB_DATA data;
 459         char *keystr;
 460         unsigned long rec_id = 0;
 461         struct idmap_tdb_common_context *ctx;
 462         TALLOC_CTX *tmp_ctx = talloc_stackframe();
 463
 464         if (!dom || !map) {
 465                 talloc_free(tmp_ctx);
 466                 return NT_STATUS_INVALID_PARAMETER;
 467         }
 468
 469         ctx =
 470             talloc_get_type_abort(dom->private_data,
 471                                   struct idmap_tdb_common_context);
 472
 473         keystr = sid_string_talloc(tmp_ctx, map->sid);
 474         if (keystr == NULL) {
 475                 DEBUG(0, ("Out of memory!\n"));
 476                 ret = NT_STATUS_NO_MEMORY;
 477                 goto done;
 478         }
 479
 480         DEBUG(10, ("Fetching record %s\n", keystr));
 481
 482         /* Check if sid is present in database */
 483         ret = dbwrap_fetch_bystring(ctx->db, tmp_ctx, keystr, &data);
 484         if (!NT_STATUS_IS_OK(ret)) {
 485                 DEBUG(10, ("Record %s not found\n", keystr));
 486                 ret = NT_STATUS_NONE_MAPPED;
 487                 goto done;
 488         }
 489
 490         /* What type of record is this ? */
 491         if (sscanf((const char *)data.dptr, "UID %lu", &rec_id) == 1) {
 492                 /* Try a UID record. */
 493                 map->xid.id = rec_id;
 494                 map->xid.type = ID_TYPE_UID;
 495                 DEBUG(10,
 496                       ("Found uid record %s -> %s \n", keystr,
 497                        (const char *)data.dptr));
 498                 ret = NT_STATUS_OK;
 499
 500         } else if (sscanf((const char *)data.dptr, "GID %lu", &rec_id) == 1) {
 501                 /* Try a GID record. */
 502                 map->xid.id = rec_id;
 503                 map->xid.type = ID_TYPE_GID;
 504                 DEBUG(10,
 505                       ("Found gid record %s -> %s \n", keystr,
 506                        (const char *)data.dptr));
 507                 ret = NT_STATUS_OK;
 508
 509         } else {                /* Unknown record type ! */
 510                 DEBUG(2,
 511                       ("Found INVALID record %s -> %s\n", keystr,
 512                        (const char *)data.dptr));
 513                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 514                 goto done;
 515         }
 516
 517         /* apply filters before returning result */
 518         if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
 519                 DEBUG(5,
 520                       ("Requested id (%u) out of range (%u - %u). Filtered!\n",
 521                        map->xid.id, dom->low_id, dom->high_id));
 522                 ret = NT_STATUS_NONE_MAPPED;
 523         }
 524
 525       done:
 526         talloc_free(tmp_ctx);
 527         return ret;
 528 }
 529
 530 /**********************************
 531  lookup a set of sids
 532 **********************************/
 533
 534 struct idmap_tdb_common_sids_to_unixids_context {
 535         struct idmap_domain *dom;
 536         struct id_map **ids;
 537         bool allocate_unmapped;
 538          NTSTATUS(*sid_to_unixid_fn) (struct idmap_domain * dom,
 539                                       struct id_map * map);
 540 };
 541
 542 static NTSTATUS idmap_tdb_common_sids_to_unixids_action(struct db_context *db,
 543                                                         void *private_data)
 544 {
 545         struct idmap_tdb_common_sids_to_unixids_context *state = private_data;
 546         size_t i, num_mapped = 0;
 547         NTSTATUS ret = NT_STATUS_OK;
 548
 549         DEBUG(10, ("idmap_tdb_common_sids_to_unixids: "
 550                    " domain: [%s], allocate: %s\n",
 551                    state->dom->name, state->allocate_unmapped ? "yes" : "no"));
 552
 553         for (i = 0; state->ids[i]; i++) {
 554                 if ((state->ids[i]->status == ID_UNKNOWN) ||
 555                     /* retry if we could not map in previous run: */
 556                     (state->ids[i]->status == ID_UNMAPPED)) {
 557                         NTSTATUS ret2;
 558
 559                         ret2 = state->sid_to_unixid_fn(state->dom,
 560                                         state->ids[i]);
 561
 562                         if (!NT_STATUS_IS_OK(ret2)) {
 563
 564                                 /* if it is just a failed mapping, continue */
 565                                 if (NT_STATUS_EQUAL
 566                                     (ret2, NT_STATUS_NONE_MAPPED)) {
 567
 568                                         /* make sure it is marked as unmapped */
 569                                         state->ids[i]->status = ID_UNMAPPED;
 570                                         ret = STATUS_SOME_UNMAPPED;
 571                                 } else {
 572                                         /*
 573                                          * some fatal error occurred,
 574                                          * return immediately
 575                                          */
 576                                         ret = ret2;
 577                                         goto done;
 578                                 }
 579                         } else {
 580                                 /* all ok, id is mapped */
 581                                 state->ids[i]->status = ID_MAPPED;
 582                         }
 583                 }
 584
 585                 if (state->ids[i]->status == ID_MAPPED) {
 586                         num_mapped += 1;
 587                 }
 588
 589                 if ((state->ids[i]->status == ID_UNMAPPED) &&
 590                     state->allocate_unmapped) {
 591                         ret =
 592                             idmap_tdb_common_new_mapping(state->dom,
 593                                                          state->ids[i]);
 594                         if (!NT_STATUS_IS_OK(ret)) {
 595                                 goto done;
 596                         }
 597                         num_mapped += 1;
 598                 }
 599         }
 600
 601 done:
 602
 603         if (NT_STATUS_IS_OK(ret) ||
 604             NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED)) {
 605                 if (i == 0 || num_mapped == 0) {
 606                         ret = NT_STATUS_NONE_MAPPED;
 607                 } else if (num_mapped < i) {
 608                         ret = STATUS_SOME_UNMAPPED;
 609                 } else {
 610                         ret = NT_STATUS_OK;
 611                 }
 612         }
 613
 614         return ret;
 615 }
 616
 617 NTSTATUS idmap_tdb_common_sids_to_unixids(struct idmap_domain * dom,
 618                                           struct id_map ** ids)
 619 {
 620         NTSTATUS ret;
 621         int i;
 622         struct idmap_tdb_common_sids_to_unixids_context state;
 623         struct idmap_tdb_common_context *ctx;
 624
 625         ctx =
 626             talloc_get_type_abort(dom->private_data,
 627                                   struct idmap_tdb_common_context);
 628
 629         /* initialize the status to avoid surprise */
 630         for (i = 0; ids[i]; i++) {
 631                 ids[i]->status = ID_UNKNOWN;
 632         }
 633
 634         state.dom = dom;
 635         state.ids = ids;
 636         state.allocate_unmapped = false;
 637         if (ctx->sid_to_unixid_fn == NULL) {
 638                 state.sid_to_unixid_fn = idmap_tdb_common_sid_to_unixid;
 639         } else {
 640                 state.sid_to_unixid_fn = ctx->sid_to_unixid_fn;
 641         }
 642
 643         ret = idmap_tdb_common_sids_to_unixids_action(ctx->db, &state);
 644
 645         if ( (NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED) ||
 646               NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) &&
 647              !dom->read_only) {
 648                 state.allocate_unmapped = true;
 649                 ret = dbwrap_trans_do(ctx->db,
 650                                       idmap_tdb_common_sids_to_unixids_action,
 651                                       &state);
 652         }
 653
 654         return ret;
 655 }