lib/dbwrap/dbwrap_ntdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Database interface wrapper around ntdb
   4    Copyright (C) Volker Lendecke 2005-2007
   5    Copyright (C) Rusty Russell 2012
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "dbwrap/dbwrap.h"
  23 #include "dbwrap/dbwrap_private.h"
  24 #include "dbwrap/dbwrap_ntdb.h"
  25 #include "system/filesys.h"
  26 #include "lib/util/util_ntdb.h"
  27 #include "ccan/str/str.h"
  28
  29 struct db_ntdb_ctx {
  30         struct ntdb_context *ntdb;
  31
  32         struct {
  33                 dev_t dev;
  34                 ino_t ino;
  35         } id;
  36 };
  37
  38 static int tdb_store_flag_to_ntdb(int tdb_flag)
  39 {
  40         switch (tdb_flag) {
  41         /* In fact, any value defaults to TDB_REPLACE in tdb! */
  42         case 0:
  43         case TDB_REPLACE:
  44                 return NTDB_REPLACE;
  45         case TDB_INSERT:
  46                 return NTDB_INSERT;
  47         case TDB_MODIFY:
  48                 return NTDB_MODIFY;
  49         default:
  50                 smb_panic("unknown tdb_flag");
  51         }
  52         return -1;      /* NOTREACHED */
  53 }
  54
  55 static NTSTATUS db_ntdb_store(struct db_record *rec, NTDB_DATA data, int flag)
  56 {
  57         int ntdb_flag = tdb_store_flag_to_ntdb(flag);
  58         struct db_ntdb_ctx *ctx = talloc_get_type_abort(rec->private_data,
  59                                                         struct db_ntdb_ctx);
  60
  61         /*
  62          * This has a bug: We need to replace rec->value for correct
  63          * operation, but right now brlock and locking don't use the value
  64          * anymore after it was stored.
  65          */
  66
  67         if (ntdb_store(ctx->ntdb, rec->key, data, ntdb_flag) == NTDB_SUCCESS) {
  68                 return NT_STATUS_OK;
  69         }
  70         return NT_STATUS_UNSUCCESSFUL;
  71 }
  72
  73 static NTSTATUS db_ntdb_delete(struct db_record *rec)
  74 {
  75         enum NTDB_ERROR err;
  76         struct db_ntdb_ctx *ctx = talloc_get_type_abort(rec->private_data,
  77                                                        struct db_ntdb_ctx);
  78
  79         err = ntdb_delete(ctx->ntdb, rec->key);
  80         if (err == NTDB_SUCCESS) {
  81                 return NT_STATUS_OK;
  82         }
  83
  84         if (err == NTDB_ERR_NOEXIST) {
  85                 return NT_STATUS_NOT_FOUND;
  86         }
  87
  88         return NT_STATUS_UNSUCCESSFUL;
  89 }
  90
  91 static void db_ntdb_log_key(const char *prefix, NTDB_DATA key)
  92 {
  93         size_t len;
  94         char *keystr;
  95
  96         if (DEBUGLEVEL < 10) {
  97                 return;
  98         }
  99         len = key.dsize;
 100         if (DEBUGLEVEL == 10) {
 101                 /*
 102                  * Only fully spam at debuglevel > 10
 103                  */
 104                 len = MIN(10, key.dsize);
 105         }
 106         keystr = hex_encode_talloc(talloc_tos(), (unsigned char *)(key.dptr),
 107                                    len);
 108         DEBUG(10, ("%s key %s\n", prefix, keystr));
 109         TALLOC_FREE(keystr);
 110 }
 111
 112 static int db_ntdb_record_destr(struct db_record* data)
 113 {
 114         struct db_ntdb_ctx *ctx =
 115                 talloc_get_type_abort(data->private_data, struct db_ntdb_ctx);
 116
 117         db_ntdb_log_key("Unlocking", data->key);
 118         ntdb_chainunlock(ctx->ntdb, data->key);
 119         return 0;
 120 }
 121
 122 struct ntdb_fetch_locked_state {
 123         TALLOC_CTX *mem_ctx;
 124         struct db_record *result;
 125 };
 126
 127 static enum NTDB_ERROR db_ntdb_fetchlock_parse(NTDB_DATA key, NTDB_DATA data,
 128                                                struct ntdb_fetch_locked_state *state)
 129 {
 130         struct db_record *result;
 131
 132         result = (struct db_record *)talloc_size(
 133                 state->mem_ctx,
 134                 sizeof(struct db_record) + key.dsize + data.dsize);
 135
 136         if (result == NULL) {
 137                 return NTDB_ERR_OOM;
 138         }
 139         state->result = result;
 140
 141         result->key.dsize = key.dsize;
 142         result->key.dptr = ((uint8_t *)result) + sizeof(struct db_record);
 143         memcpy(result->key.dptr, key.dptr, key.dsize);
 144
 145         result->value.dsize = data.dsize;
 146
 147         if (data.dsize > 0) {
 148                 result->value.dptr = result->key.dptr+key.dsize;
 149                 memcpy(result->value.dptr, data.dptr, data.dsize);
 150         }
 151         else {
 152                 result->value.dptr = NULL;
 153         }
 154
 155         return NTDB_SUCCESS;
 156 }
 157
 158 static struct db_record *db_ntdb_fetch_locked_internal(
 159         struct db_context *db, TALLOC_CTX *mem_ctx, NTDB_DATA key)
 160 {
 161         struct db_ntdb_ctx *ctx = talloc_get_type_abort(db->private_data,
 162                                                         struct db_ntdb_ctx);
 163         struct ntdb_fetch_locked_state state;
 164         enum NTDB_ERROR err;
 165         NTDB_DATA null = { NULL, 0 };
 166
 167         state.mem_ctx = mem_ctx;
 168         state.result = NULL;
 169
 170         err = ntdb_parse_record(ctx->ntdb, key, db_ntdb_fetchlock_parse,
 171                                 &state);
 172         if (err != NTDB_SUCCESS && err != NTDB_ERR_NOEXIST) {
 173                 ntdb_chainunlock(ctx->ntdb, key);
 174                 return NULL;
 175         }
 176
 177         if (state.result == NULL) {
 178                 db_ntdb_fetchlock_parse(key, null, &state);
 179         }
 180
 181         if (state.result == NULL) {
 182                 ntdb_chainunlock(ctx->ntdb, key);
 183                 return NULL;
 184         }
 185
 186         talloc_set_destructor(state.result, db_ntdb_record_destr);
 187
 188         state.result->private_data = talloc_reference(state.result, ctx);
 189         state.result->store = db_ntdb_store;
 190         state.result->delete_rec = db_ntdb_delete;
 191
 192         DEBUG(10, ("Allocated locked data 0x%p\n", state.result));
 193
 194         return state.result;
 195 }
 196
 197 static struct db_record *db_ntdb_fetch_locked(
 198         struct db_context *db, TALLOC_CTX *mem_ctx, NTDB_DATA key)
 199 {
 200         struct db_ntdb_ctx *ctx = talloc_get_type_abort(db->private_data,
 201                                                        struct db_ntdb_ctx);
 202
 203         db_ntdb_log_key("Locking", key);
 204         if (ntdb_chainlock(ctx->ntdb, key) != 0) {
 205                 DEBUG(3, ("ntdb_chainlock failed\n"));
 206                 return NULL;
 207         }
 208         return db_ntdb_fetch_locked_internal(db, mem_ctx, key);
 209 }
 210
 211 /* Proxy which sets waitflag to false so we never block. */
 212 static int lock_nonblock(int fd, int rw, off_t off, off_t len, bool waitflag,
 213                          void *_orig)
 214 {
 215         struct ntdb_attribute_flock *orig = _orig;
 216
 217         return orig->lock(fd, rw, off, len, false, orig->data);
 218 }
 219
 220 static enum NTDB_ERROR enable_nonblock(struct ntdb_context *ntdb,
 221                                        union ntdb_attribute *orig)
 222 {
 223         union ntdb_attribute locking;
 224         enum NTDB_ERROR ecode;
 225
 226         orig->base.attr = NTDB_ATTRIBUTE_FLOCK;
 227         ecode = ntdb_get_attribute(ntdb, orig);
 228         if (ecode != NTDB_SUCCESS) {
 229                 return ecode;
 230         }
 231
 232         /* Replace locking function with our own. */
 233         locking = *orig;
 234         locking.flock.data = orig;
 235         locking.flock.lock = lock_nonblock;
 236
 237         return ntdb_set_attribute(ntdb, &locking);
 238 }
 239
 240 static void disable_nonblock(struct ntdb_context *ntdb)
 241 {
 242         ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_FLOCK);
 243 }
 244
 245 static enum NTDB_ERROR ntdb_chainlock_nonblock(struct ntdb_context *ntdb,
 246                                                NTDB_DATA key)
 247 {
 248         union ntdb_attribute orig;
 249         enum NTDB_ERROR ecode;
 250
 251         ecode = enable_nonblock(ntdb, &orig);
 252         if (!ecode) {
 253                 ecode = ntdb_chainlock(ntdb, key);
 254                 disable_nonblock(ntdb);
 255         }
 256         return ecode;
 257 }
 258
 259 static struct db_record *db_ntdb_try_fetch_locked(
 260         struct db_context *db, TALLOC_CTX *mem_ctx, TDB_DATA key)
 261 {
 262         struct db_ntdb_ctx *ctx = talloc_get_type_abort(db->private_data,
 263                                                        struct db_ntdb_ctx);
 264
 265         db_ntdb_log_key("Trying to lock", key);
 266         if (ntdb_chainlock_nonblock(ctx->ntdb, key) != 0) {
 267                 DEBUG(3, ("ntdb_chainlock_nonblock failed\n"));
 268                 return NULL;
 269         }
 270         return db_ntdb_fetch_locked_internal(db, mem_ctx, key);
 271 }
 272
 273 static int db_ntdb_exists(struct db_context *db, TDB_DATA key)
 274 {
 275         struct db_ntdb_ctx *ctx = talloc_get_type_abort(
 276                 db->private_data, struct db_ntdb_ctx);
 277         return ntdb_exists(ctx->ntdb, key);
 278 }
 279
 280 static int db_ntdb_wipe(struct db_context *db)
 281 {
 282         struct db_ntdb_ctx *ctx = talloc_get_type_abort(
 283                 db->private_data, struct db_ntdb_ctx);
 284         if (ntdb_wipe_all(ctx->ntdb) != NTDB_SUCCESS) {
 285                 return -1;
 286         }
 287         return 0;
 288 }
 289
 290 static int db_ntdb_check(struct db_context *db)
 291 {
 292         struct db_ntdb_ctx *ctx = talloc_get_type_abort(
 293                 db->private_data, struct db_ntdb_ctx);
 294         if (ntdb_check(ctx->ntdb, NULL, NULL) != NTDB_SUCCESS) {
 295                 return -1;
 296         }
 297         return 0;
 298 }
 299
 300 struct db_ntdb_parse_state {
 301         void (*parser)(TDB_DATA key, TDB_DATA data,
 302                        void *private_data);
 303         void *private_data;
 304 };
 305
 306 /*
 307  * ntdb_parse_record expects a parser returning enum NTDB_ERROR,
 308  * mixing up ntdb and parser errors. Wrap around that by always
 309  * returning NTDB_SUCCESS and have dbwrap_parse_record expect a parser
 310  * returning void.
 311  */
 312
 313 static enum NTDB_ERROR db_ntdb_parser(NTDB_DATA key, NTDB_DATA data,
 314                                       struct db_ntdb_parse_state *state)
 315 {
 316         state->parser(key, data, state->private_data);
 317         return NTDB_SUCCESS;
 318 }
 319
 320 static NTSTATUS db_ntdb_parse(struct db_context *db, TDB_DATA key,
 321                               void (*parser)(TDB_DATA key, TDB_DATA data,
 322                                              void *private_data),
 323                               void *private_data)
 324 {
 325         struct db_ntdb_ctx *ctx = talloc_get_type_abort(
 326                 db->private_data, struct db_ntdb_ctx);
 327         struct db_ntdb_parse_state state;
 328         enum NTDB_ERROR err;
 329
 330         state.parser = parser;
 331         state.private_data = private_data;
 332
 333         err = ntdb_parse_record(ctx->ntdb, key, db_ntdb_parser, &state);
 334         return map_nt_error_from_ntdb(err);
 335 }
 336
 337 struct db_ntdb_traverse_ctx {
 338         struct db_context *db;
 339         int (*f)(struct db_record *rec, void *private_data);
 340         void *private_data;
 341 };
 342
 343 static int db_ntdb_traverse_func(struct ntdb_context *ntdb,
 344                                  NTDB_DATA kbuf, NTDB_DATA dbuf,
 345                                  struct db_ntdb_traverse_ctx *ctx)
 346 {
 347         struct db_record rec;
 348
 349         rec.key = kbuf;
 350         rec.value = dbuf;
 351         rec.store = db_ntdb_store;
 352         rec.delete_rec = db_ntdb_delete;
 353         rec.private_data = ctx->db->private_data;
 354         rec.db = ctx->db;
 355
 356         return ctx->f(&rec, ctx->private_data);
 357 }
 358
 359 static int db_ntdb_traverse(struct db_context *db,
 360                             int (*f)(struct db_record *rec, void *private_data),
 361                             void *private_data)
 362 {
 363         struct db_ntdb_ctx *db_ctx =
 364                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 365         struct db_ntdb_traverse_ctx ctx;
 366         int64_t ret;
 367
 368         ctx.db = db;
 369         ctx.f = f;
 370         ctx.private_data = private_data;
 371         ret = ntdb_traverse(db_ctx->ntdb, db_ntdb_traverse_func, &ctx);
 372
 373         if (ret < 0) {
 374                 return -1;
 375         }
 376
 377         /* Make sure we don't truncate! */
 378         if ((int)ret != ret) {
 379                 ret = INT_MAX;
 380         }
 381         return ret;
 382 }
 383
 384 static NTSTATUS db_ntdb_store_deny(struct db_record *rec, NTDB_DATA data, int flag)
 385 {
 386         return NT_STATUS_MEDIA_WRITE_PROTECTED;
 387 }
 388
 389 static NTSTATUS db_ntdb_delete_deny(struct db_record *rec)
 390 {
 391         return NT_STATUS_MEDIA_WRITE_PROTECTED;
 392 }
 393
 394 static int db_ntdb_traverse_read_func(struct ntdb_context *ntdb,
 395                                       NTDB_DATA kbuf, NTDB_DATA dbuf,
 396                                       struct db_ntdb_traverse_ctx *ctx)
 397 {
 398         struct db_record rec;
 399
 400         rec.key = kbuf;
 401         rec.value = dbuf;
 402         rec.store = db_ntdb_store_deny;
 403         rec.delete_rec = db_ntdb_delete_deny;
 404         rec.private_data = ctx->db->private_data;
 405         rec.db = ctx->db;
 406
 407         return ctx->f(&rec, ctx->private_data);
 408 }
 409
 410 static int db_ntdb_traverse_read(struct db_context *db,
 411                                  int (*f)(struct db_record *rec,
 412                                           void *private_data),
 413                                  void *private_data)
 414 {
 415         struct db_ntdb_ctx *db_ctx =
 416                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 417         struct db_ntdb_traverse_ctx ctx;
 418         int64_t ret;
 419
 420         ctx.db = db;
 421         ctx.f = f;
 422         ctx.private_data = private_data;
 423
 424         /* This is a bit of paranoia to check that f() isn't altering
 425          * database. */
 426         if (ntdb_get_flags(db_ctx->ntdb) & NTDB_RDONLY) {
 427                 ret = ntdb_traverse(db_ctx->ntdb, db_ntdb_traverse_read_func,
 428                                     &ctx);
 429         } else {
 430                 ntdb_add_flag(db_ctx->ntdb, NTDB_RDONLY);
 431                 ret = ntdb_traverse(db_ctx->ntdb, db_ntdb_traverse_read_func,
 432                                     &ctx);
 433                 ntdb_remove_flag(db_ctx->ntdb, NTDB_RDONLY);
 434         }
 435
 436         if (ret < 0) {
 437                 return -1;
 438         }
 439
 440         /* Make sure we don't truncate! */
 441         if ((int)ret != ret) {
 442                 ret = INT_MAX;
 443         }
 444         return ret;
 445 }
 446
 447 static int db_ntdb_get_seqnum(struct db_context *db)
 448
 449 {
 450         struct db_ntdb_ctx *db_ctx =
 451                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 452         return ntdb_get_seqnum(db_ctx->ntdb);
 453 }
 454
 455 static int db_ntdb_transaction_start(struct db_context *db)
 456 {
 457         struct db_ntdb_ctx *db_ctx =
 458                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 459         return ntdb_transaction_start(db_ctx->ntdb) == NTDB_SUCCESS ? 0 : -1;
 460 }
 461
 462 static NTSTATUS db_ntdb_transaction_start_nonblock(struct db_context *db)
 463 {
 464         union ntdb_attribute orig;
 465         enum NTDB_ERROR ecode;
 466         struct db_ntdb_ctx *db_ctx =
 467                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 468
 469         ecode = enable_nonblock(db_ctx->ntdb, &orig);
 470         if (!ecode) {
 471                 ecode = ntdb_transaction_start(db_ctx->ntdb);
 472                 disable_nonblock(db_ctx->ntdb);
 473         }
 474         return map_nt_error_from_ntdb(ecode);
 475 }
 476
 477 static int db_ntdb_transaction_commit(struct db_context *db)
 478 {
 479         struct db_ntdb_ctx *db_ctx =
 480                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 481         return ntdb_transaction_commit(db_ctx->ntdb) == NTDB_SUCCESS ? 0 : -1;
 482 }
 483
 484 static int db_ntdb_transaction_cancel(struct db_context *db)
 485 {
 486         struct db_ntdb_ctx *db_ctx =
 487                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 488         ntdb_transaction_cancel(db_ctx->ntdb);
 489         return 0;
 490 }
 491
 492 static void db_ntdb_id(struct db_context *db, const uint8_t **id, size_t *idlen)
 493 {
 494         struct db_ntdb_ctx *db_ctx =
 495                 talloc_get_type_abort(db->private_data, struct db_ntdb_ctx);
 496         *id = (uint8_t *)&db_ctx->id;
 497         *idlen = sizeof(db_ctx->id);
 498 }
 499
 500 /* Don't ask this to open a .tdb file: dbwrap_local_open will catch that. */
 501 struct db_context *db_open_ntdb(TALLOC_CTX *mem_ctx,
 502                                 struct loadparm_context *lp_ctx,
 503                                 const char *ntdbname,
 504                                 int hash_size, int ntdb_flags,
 505                                 int open_flags, mode_t mode,
 506                                 enum dbwrap_lock_order lock_order,
 507                                 uint64_t dbwrap_flags)
 508 {
 509         struct db_context *result = NULL;
 510         struct db_ntdb_ctx *db_ntdb;
 511         struct stat st;
 512         union ntdb_attribute hattr;
 513
 514         if ((ntdb_flags & NTDB_INTERNAL) && !ntdbname) {
 515                 ntdbname = "unnamed";
 516         }
 517
 518         /* Extra paranoia. */
 519         if (strends(ntdbname, ".tdb")) {
 520                 DEBUG(0, ("can't try to open %s with ntdb!", ntdbname));
 521                 return NULL;
 522         }
 523
 524         /* We only use this if hsize is non-zero. */
 525         hattr.base.attr = NTDB_ATTRIBUTE_HASHSIZE;
 526         hattr.base.next = NULL;
 527         hattr.hashsize.size = hash_size;
 528
 529         result = talloc_zero(mem_ctx, struct db_context);
 530         if (result == NULL) {
 531                 DEBUG(0, ("talloc failed\n"));
 532                 goto fail;
 533         }
 534
 535         result->private_data = db_ntdb = talloc(result, struct db_ntdb_ctx);
 536         if (db_ntdb == NULL) {
 537                 DEBUG(0, ("talloc failed\n"));
 538                 goto fail;
 539         }
 540         result->lock_order = lock_order;
 541
 542         db_ntdb->ntdb = ntdb_new(db_ntdb, ntdbname, ntdb_flags,
 543                                  open_flags, mode,
 544                                  hash_size ? &hattr : NULL, lp_ctx);
 545         if (db_ntdb->ntdb == NULL) {
 546                 DEBUG(3, ("Could not open ntdb %s: %s\n",
 547                           ntdbname, strerror(errno)));
 548                 goto fail;
 549         }
 550
 551         ZERO_STRUCT(db_ntdb->id);
 552
 553         if (fstat(ntdb_fd(db_ntdb->ntdb), &st) == -1) {
 554                 DEBUG(3, ("fstat failed: %s\n", strerror(errno)));
 555                 goto fail;
 556         }
 557         db_ntdb->id.dev = st.st_dev;
 558         db_ntdb->id.ino = st.st_ino;
 559
 560         result->fetch_locked = db_ntdb_fetch_locked;
 561         result->try_fetch_locked = db_ntdb_try_fetch_locked;
 562         result->traverse = db_ntdb_traverse;
 563         result->traverse_read = db_ntdb_traverse_read;
 564         result->parse_record = db_ntdb_parse;
 565         result->get_seqnum = db_ntdb_get_seqnum;
 566         result->persistent = ((ntdb_flags & NTDB_CLEAR_IF_FIRST) == 0);
 567         result->transaction_start = db_ntdb_transaction_start;
 568         result->transaction_start_nonblock = db_ntdb_transaction_start_nonblock;
 569         result->transaction_commit = db_ntdb_transaction_commit;
 570         result->transaction_cancel = db_ntdb_transaction_cancel;
 571         result->exists = db_ntdb_exists;
 572         result->wipe = db_ntdb_wipe;
 573         result->id = db_ntdb_id;
 574         result->check = db_ntdb_check;
 575         result->stored_callback = NULL;
 576         result->name = ntdb_name(db_ntdb->ntdb);
 577         result->hash_size = hash_size;
 578         return result;
 579
 580  fail:
 581         if (result != NULL) {
 582                 TALLOC_FREE(result);
 583         }
 584         return NULL;
 585 }