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