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         struct dom_sid_buf ksidstr;
 225         char *kidstr = NULL;
 226
 227         if (!map || !map->sid) {
 228                 return NT_STATUS_INVALID_PARAMETER;
 229         }
 230
 231         /* TODO: should we filter a set_mapping using low/high filters ? */
 232
 233         ctx =
 234             talloc_get_type_abort(dom->private_data,
 235                                   struct idmap_tdb_common_context);
 236
 237         switch (map->xid.type) {
 238
 239         case ID_TYPE_UID:
 240                 kidstr =
 241                     talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
 242                 break;
 243
 244         case ID_TYPE_GID:
 245                 kidstr =
 246                     talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
 247                 break;
 248
 249         default:
 250                 DEBUG(2, ("INVALID unix ID type: 0x%02x\n", map->xid.type));
 251                 return NT_STATUS_INVALID_PARAMETER;
 252         }
 253
 254         if (kidstr == NULL) {
 255                 DEBUG(0, ("ERROR: Out of memory!\n"));
 256                 ret = NT_STATUS_NO_MEMORY;
 257                 goto done;
 258         }
 259
 260         state.ksidstr = dom_sid_str_buf(map->sid, &ksidstr);
 261         state.kidstr = kidstr;
 262
 263         ret = dbwrap_trans_do(ctx->db, idmap_tdb_common_set_mapping_action,
 264                               &state);
 265
 266       done:
 267         talloc_free(kidstr);
 268         return ret;
 269 }
 270
 271 /*
 272  * Create a new mapping for an unmapped SID, also allocating a new ID.
 273  * This should be run inside a transaction.
 274  *
 275  * TODO:
 276  *  Properly integrate this with multi domain idmap config:
 277  *  Currently, the allocator is default-config only.
 278  */
 279 NTSTATUS idmap_tdb_common_new_mapping(struct idmap_domain * dom,
 280                                       struct id_map * map)
 281 {
 282         NTSTATUS ret;
 283         struct idmap_tdb_common_context *ctx;
 284
 285         ctx =
 286             talloc_get_type_abort(dom->private_data,
 287                                   struct idmap_tdb_common_context);
 288
 289         ret = idmap_rw_new_mapping(dom, ctx->rw_ops, map);
 290
 291         return ret;
 292 }
 293
 294 /*
 295   lookup a set of unix ids
 296 */
 297 NTSTATUS idmap_tdb_common_unixids_to_sids(struct idmap_domain * dom,
 298                                           struct id_map ** ids)
 299 {
 300         NTSTATUS ret;
 301         size_t i, num_mapped = 0;
 302         struct idmap_tdb_common_context *ctx;
 303
 304         NTSTATUS(*unixid_to_sid_fn) (struct idmap_domain * dom,
 305                                      struct id_map * map);
 306         ctx =
 307             talloc_get_type_abort(dom->private_data,
 308                                   struct idmap_tdb_common_context);
 309
 310         if (ctx->unixid_to_sid_fn == NULL) {
 311                 unixid_to_sid_fn = idmap_tdb_common_unixid_to_sid;
 312         } else {
 313                 unixid_to_sid_fn = ctx->unixid_to_sid_fn;
 314         }
 315
 316         /* initialize the status to avoid surprise */
 317         for (i = 0; ids[i]; i++) {
 318                 ids[i]->status = ID_UNKNOWN;
 319         }
 320
 321         for (i = 0; ids[i]; i++) {
 322                 ret = unixid_to_sid_fn(dom, ids[i]);
 323                 if (!NT_STATUS_IS_OK(ret)) {
 324
 325                         /* if it is just a failed mapping continue */
 326                         if (NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) {
 327
 328                                 /* make sure it is marked as unmapped */
 329                                 ids[i]->status = ID_UNMAPPED;
 330                                 continue;
 331                         }
 332
 333                         /* some fatal error occurred, return immediately */
 334                         goto done;
 335                 }
 336
 337                 /* all ok, id is mapped */
 338                 ids[i]->status = ID_MAPPED;
 339                 num_mapped += 1;
 340         }
 341
 342         ret = NT_STATUS_OK;
 343
 344 done:
 345
 346         if (NT_STATUS_IS_OK(ret)) {
 347                 if (i == 0 || num_mapped == 0) {
 348                         ret = NT_STATUS_NONE_MAPPED;
 349                 } else if (num_mapped < i) {
 350                         ret = STATUS_SOME_UNMAPPED;
 351                 } else {
 352                         ret = NT_STATUS_OK;
 353                 }
 354         }
 355
 356         return ret;
 357 }
 358
 359 /*
 360   default single id to sid lookup function
 361 */
 362 NTSTATUS idmap_tdb_common_unixid_to_sid(struct idmap_domain * dom,
 363                                         struct id_map * map)
 364 {
 365         NTSTATUS ret;
 366         TDB_DATA data;
 367         char *keystr;
 368         struct idmap_tdb_common_context *ctx;
 369
 370         if (!dom || !map) {
 371                 return NT_STATUS_INVALID_PARAMETER;
 372         }
 373
 374         ctx =
 375             talloc_get_type_abort(dom->private_data,
 376                                   struct idmap_tdb_common_context);
 377
 378         /* apply filters before checking */
 379         if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
 380                 DEBUG(5,
 381                       ("Requested id (%u) out of range (%u - %u). Filtered!\n",
 382                        map->xid.id, dom->low_id, dom->high_id));
 383                 return NT_STATUS_NONE_MAPPED;
 384         }
 385
 386         switch (map->xid.type) {
 387
 388         case ID_TYPE_UID:
 389                 keystr =
 390                     talloc_asprintf(ctx, "UID %lu", (unsigned long)map->xid.id);
 391                 break;
 392
 393         case ID_TYPE_GID:
 394                 keystr =
 395                     talloc_asprintf(ctx, "GID %lu", (unsigned long)map->xid.id);
 396                 break;
 397
 398         default:
 399                 DEBUG(2, ("INVALID unix ID type: 0x%02x\n", map->xid.type));
 400                 return NT_STATUS_INVALID_PARAMETER;
 401         }
 402
 403         if (keystr == NULL) {
 404                 DEBUG(0, ("Out of memory!\n"));
 405                 ret = NT_STATUS_NO_MEMORY;
 406                 goto done;
 407         }
 408
 409         DEBUG(10, ("Fetching record %s\n", keystr));
 410
 411         /* Check if the mapping exists */
 412         ret = dbwrap_fetch_bystring(ctx->db, keystr, keystr, &data);
 413
 414         if (!NT_STATUS_IS_OK(ret)) {
 415                 DEBUG(10, ("Record %s not found\n", keystr));
 416                 ret = NT_STATUS_NONE_MAPPED;
 417                 goto done;
 418         }
 419
 420         if ((data.dsize == 0) || (data.dptr[data.dsize-1] != '\0')) {
 421                 DBG_DEBUG("Invalid record length %zu\n", data.dsize);
 422                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 423                 goto done;
 424         }
 425
 426         if (!string_to_sid(map->sid, (const char *)data.dptr)) {
 427                 DEBUG(10, ("INVALID SID (%s) in record %s\n",
 428                            (const char *)data.dptr, keystr));
 429                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 430                 goto done;
 431         }
 432
 433         DEBUG(10, ("Found record %s -> %s\n", keystr, (const char *)data.dptr));
 434         ret = NT_STATUS_OK;
 435
 436       done:
 437         talloc_free(keystr);
 438         return ret;
 439 }
 440
 441 /**********************************
 442  Single sid to id lookup function.
 443 **********************************/
 444
 445 NTSTATUS idmap_tdb_common_sid_to_unixid(struct idmap_domain * dom,
 446                                         struct id_map * map)
 447 {
 448         NTSTATUS ret;
 449         TDB_DATA data;
 450         struct dom_sid_buf keystr;
 451         unsigned long rec_id = 0;
 452         struct idmap_tdb_common_context *ctx;
 453         TALLOC_CTX *tmp_ctx = talloc_stackframe();
 454
 455         if (!dom || !map) {
 456                 talloc_free(tmp_ctx);
 457                 return NT_STATUS_INVALID_PARAMETER;
 458         }
 459
 460         ctx =
 461             talloc_get_type_abort(dom->private_data,
 462                                   struct idmap_tdb_common_context);
 463
 464         dom_sid_str_buf(map->sid, &keystr);
 465
 466         DEBUG(10, ("Fetching record %s\n", keystr.buf));
 467
 468         /* Check if sid is present in database */
 469         ret = dbwrap_fetch_bystring(ctx->db, tmp_ctx, keystr.buf, &data);
 470         if (!NT_STATUS_IS_OK(ret)) {
 471                 DEBUG(10, ("Record %s not found\n", keystr.buf));
 472                 ret = NT_STATUS_NONE_MAPPED;
 473                 goto done;
 474         }
 475
 476         /* What type of record is this ? */
 477         if (sscanf((const char *)data.dptr, "UID %lu", &rec_id) == 1) {
 478                 /* Try a UID record. */
 479                 map->xid.id = rec_id;
 480                 map->xid.type = ID_TYPE_UID;
 481                 DEBUG(10,
 482                       ("Found uid record %s -> %s \n", keystr.buf,
 483                        (const char *)data.dptr));
 484                 ret = NT_STATUS_OK;
 485
 486         } else if (sscanf((const char *)data.dptr, "GID %lu", &rec_id) == 1) {
 487                 /* Try a GID record. */
 488                 map->xid.id = rec_id;
 489                 map->xid.type = ID_TYPE_GID;
 490                 DEBUG(10,
 491                       ("Found gid record %s -> %s \n", keystr.buf,
 492                        (const char *)data.dptr));
 493                 ret = NT_STATUS_OK;
 494
 495         } else {                /* Unknown record type ! */
 496                 DEBUG(2,
 497                       ("Found INVALID record %s -> %s\n", keystr.buf,
 498                        (const char *)data.dptr));
 499                 ret = NT_STATUS_INTERNAL_DB_ERROR;
 500                 goto done;
 501         }
 502
 503         /* apply filters before returning result */
 504         if (!idmap_unix_id_is_in_range(map->xid.id, dom)) {
 505                 DEBUG(5,
 506                       ("Requested id (%u) out of range (%u - %u). Filtered!\n",
 507                        map->xid.id, dom->low_id, dom->high_id));
 508                 ret = NT_STATUS_NONE_MAPPED;
 509         }
 510
 511       done:
 512         talloc_free(tmp_ctx);
 513         return ret;
 514 }
 515
 516 /**********************************
 517  lookup a set of sids
 518 **********************************/
 519
 520 struct idmap_tdb_common_sids_to_unixids_context {
 521         struct idmap_domain *dom;
 522         struct id_map **ids;
 523         bool allocate_unmapped;
 524          NTSTATUS(*sid_to_unixid_fn) (struct idmap_domain * dom,
 525                                       struct id_map * map);
 526 };
 527
 528 static NTSTATUS idmap_tdb_common_sids_to_unixids_action(struct db_context *db,
 529                                                         void *private_data)
 530 {
 531         struct idmap_tdb_common_sids_to_unixids_context *state = private_data;
 532         size_t i, num_mapped = 0;
 533         NTSTATUS ret = NT_STATUS_OK;
 534
 535         DEBUG(10, ("idmap_tdb_common_sids_to_unixids: "
 536                    " domain: [%s], allocate: %s\n",
 537                    state->dom->name, state->allocate_unmapped ? "yes" : "no"));
 538
 539         for (i = 0; state->ids[i]; i++) {
 540                 if ((state->ids[i]->status == ID_UNKNOWN) ||
 541                     /* retry if we could not map in previous run: */
 542                     (state->ids[i]->status == ID_UNMAPPED)) {
 543                         NTSTATUS ret2;
 544
 545                         ret2 = state->sid_to_unixid_fn(state->dom,
 546                                         state->ids[i]);
 547
 548                         if (!NT_STATUS_IS_OK(ret2)) {
 549
 550                                 /* if it is just a failed mapping, continue */
 551                                 if (NT_STATUS_EQUAL
 552                                     (ret2, NT_STATUS_NONE_MAPPED)) {
 553
 554                                         /* make sure it is marked as unmapped */
 555                                         state->ids[i]->status = ID_UNMAPPED;
 556                                         ret = STATUS_SOME_UNMAPPED;
 557                                 } else {
 558                                         /*
 559                                          * some fatal error occurred,
 560                                          * return immediately
 561                                          */
 562                                         ret = ret2;
 563                                         goto done;
 564                                 }
 565                         } else {
 566                                 /* all ok, id is mapped */
 567                                 state->ids[i]->status = ID_MAPPED;
 568                         }
 569                 }
 570
 571                 if (state->ids[i]->status == ID_MAPPED) {
 572                         num_mapped += 1;
 573                 }
 574
 575                 if ((state->ids[i]->status == ID_UNMAPPED) &&
 576                     state->allocate_unmapped) {
 577                         ret =
 578                             idmap_tdb_common_new_mapping(state->dom,
 579                                                          state->ids[i]);
 580                         DBG_DEBUG("idmap_tdb_common_new_mapping returned %s\n",
 581                                   nt_errstr(ret));
 582                         if (!NT_STATUS_IS_OK(ret)) {
 583                                 ret = STATUS_SOME_UNMAPPED;
 584                                 continue;
 585                         }
 586                         num_mapped += 1;
 587                 }
 588         }
 589
 590 done:
 591
 592         if (NT_STATUS_IS_OK(ret) ||
 593             NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED)) {
 594                 if (i == 0 || num_mapped == 0) {
 595                         ret = NT_STATUS_NONE_MAPPED;
 596                 } else if (num_mapped < i) {
 597                         ret = STATUS_SOME_UNMAPPED;
 598                 } else {
 599                         ret = NT_STATUS_OK;
 600                 }
 601         }
 602
 603         return ret;
 604 }
 605
 606 NTSTATUS idmap_tdb_common_sids_to_unixids(struct idmap_domain * dom,
 607                                           struct id_map ** ids)
 608 {
 609         NTSTATUS ret;
 610         int i;
 611         struct idmap_tdb_common_sids_to_unixids_context state;
 612         struct idmap_tdb_common_context *ctx;
 613
 614         ctx =
 615             talloc_get_type_abort(dom->private_data,
 616                                   struct idmap_tdb_common_context);
 617
 618         /* initialize the status to avoid surprise */
 619         for (i = 0; ids[i]; i++) {
 620                 ids[i]->status = ID_UNKNOWN;
 621         }
 622
 623         state.dom = dom;
 624         state.ids = ids;
 625         state.allocate_unmapped = false;
 626         if (ctx->sid_to_unixid_fn == NULL) {
 627                 state.sid_to_unixid_fn = idmap_tdb_common_sid_to_unixid;
 628         } else {
 629                 state.sid_to_unixid_fn = ctx->sid_to_unixid_fn;
 630         }
 631
 632         ret = idmap_tdb_common_sids_to_unixids_action(ctx->db, &state);
 633
 634         if ( (NT_STATUS_EQUAL(ret, STATUS_SOME_UNMAPPED) ||
 635               NT_STATUS_EQUAL(ret, NT_STATUS_NONE_MAPPED)) &&
 636              !dom->read_only) {
 637                 state.allocate_unmapped = true;
 638                 ret = dbwrap_trans_do(ctx->db,
 639                                       idmap_tdb_common_sids_to_unixids_action,
 640                                       &state);
 641         }
 642
 643         return ret;
 644 }