source3/lib/util_tdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    tdb utility functions
   4    Copyright (C) Andrew Tridgell   1992-1998
   5    Copyright (C) Rafal Szczesniak  2002
   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 #undef malloc
  23 #undef realloc
  24 #undef calloc
  25 #undef strdup
  26
  27 /* these are little tdb utility functions that are meant to make
  28    dealing with a tdb database a little less cumbersome in Samba */
  29
  30 static SIG_ATOMIC_T gotalarm;
  31
  32 /***************************************************************
  33  Signal function to tell us we timed out.
  34 ****************************************************************/
  35
  36 static void gotalarm_sig(void)
  37 {
  38         gotalarm = 1;
  39 }
  40
  41 /***************************************************************
  42  Make a TDB_DATA and keep the const warning in one place
  43 ****************************************************************/
  44
  45 TDB_DATA make_tdb_data(const uint8 *dptr, size_t dsize)
  46 {
  47         TDB_DATA ret;
  48         ret.dptr = CONST_DISCARD(uint8 *, dptr);
  49         ret.dsize = dsize;
  50         return ret;
  51 }
  52
  53 TDB_DATA string_tdb_data(const char *string)
  54 {
  55         return make_tdb_data((const uint8 *)string, string ? strlen(string) : 0 );
  56 }
  57
  58 TDB_DATA string_term_tdb_data(const char *string)
  59 {
  60         return make_tdb_data((const uint8 *)string, string ? strlen(string) + 1 : 0);
  61 }
  62
  63 /****************************************************************************
  64  Lock a chain with timeout (in seconds).
  65 ****************************************************************************/
  66
  67 static int tdb_chainlock_with_timeout_internal( TDB_CONTEXT *tdb, TDB_DATA key, unsigned int timeout, int rw_type)
  68 {
  69         /* Allow tdb_chainlock to be interrupted by an alarm. */
  70         int ret;
  71         gotalarm = 0;
  72
  73         if (timeout) {
  74                 CatchSignal(SIGALRM, SIGNAL_CAST gotalarm_sig);
  75                 tdb_setalarm_sigptr(tdb, &gotalarm);
  76                 alarm(timeout);
  77         }
  78
  79         if (rw_type == F_RDLCK)
  80                 ret = tdb_chainlock_read(tdb, key);
  81         else
  82                 ret = tdb_chainlock(tdb, key);
  83
  84         if (timeout) {
  85                 alarm(0);
  86                 tdb_setalarm_sigptr(tdb, NULL);
  87                 CatchSignal(SIGALRM, SIGNAL_CAST SIG_IGN);
  88                 if (gotalarm) {
  89                         DEBUG(0,("tdb_chainlock_with_timeout_internal: alarm (%u) timed out for key %s in tdb %s\n",
  90                                 timeout, key.dptr, tdb_name(tdb)));
  91                         /* TODO: If we time out waiting for a lock, it might
  92                          * be nice to use F_GETLK to get the pid of the
  93                          * process currently holding the lock and print that
  94                          * as part of the debugging message. -- mbp */
  95                         return -1;
  96                 }
  97         }
  98
  99         return ret;
 100 }
 101
 102 /****************************************************************************
 103  Write lock a chain. Return -1 if timeout or lock failed.
 104 ****************************************************************************/
 105
 106 int tdb_chainlock_with_timeout( TDB_CONTEXT *tdb, TDB_DATA key, unsigned int timeout)
 107 {
 108         return tdb_chainlock_with_timeout_internal(tdb, key, timeout, F_WRLCK);
 109 }
 110
 111 /****************************************************************************
 112  Lock a chain by string. Return -1 if timeout or lock failed.
 113 ****************************************************************************/
 114
 115 int tdb_lock_bystring(TDB_CONTEXT *tdb, const char *keyval)
 116 {
 117         TDB_DATA key = string_term_tdb_data(keyval);
 118
 119         return tdb_chainlock(tdb, key);
 120 }
 121
 122 int tdb_lock_bystring_with_timeout(TDB_CONTEXT *tdb, const char *keyval,
 123                                    int timeout)
 124 {
 125         TDB_DATA key = string_term_tdb_data(keyval);
 126
 127         return tdb_chainlock_with_timeout(tdb, key, timeout);
 128 }
 129
 130 /****************************************************************************
 131  Unlock a chain by string.
 132 ****************************************************************************/
 133
 134 void tdb_unlock_bystring(TDB_CONTEXT *tdb, const char *keyval)
 135 {
 136         TDB_DATA key = string_term_tdb_data(keyval);
 137
 138         tdb_chainunlock(tdb, key);
 139 }
 140
 141 /****************************************************************************
 142  Read lock a chain by string. Return -1 if timeout or lock failed.
 143 ****************************************************************************/
 144
 145 int tdb_read_lock_bystring_with_timeout(TDB_CONTEXT *tdb, const char *keyval, unsigned int timeout)
 146 {
 147         TDB_DATA key = string_term_tdb_data(keyval);
 148
 149         return tdb_chainlock_with_timeout_internal(tdb, key, timeout, F_RDLCK);
 150 }
 151
 152 /****************************************************************************
 153  Read unlock a chain by string.
 154 ****************************************************************************/
 155
 156 void tdb_read_unlock_bystring(TDB_CONTEXT *tdb, const char *keyval)
 157 {
 158         TDB_DATA key = string_term_tdb_data(keyval);
 159
 160         tdb_chainunlock_read(tdb, key);
 161 }
 162
 163
 164 /****************************************************************************
 165  Fetch a int32 value by a arbitrary blob key, return -1 if not found.
 166  Output is int32 in native byte order.
 167 ****************************************************************************/
 168
 169 int32 tdb_fetch_int32_byblob(TDB_CONTEXT *tdb, TDB_DATA key)
 170 {
 171         TDB_DATA data;
 172         int32 ret;
 173
 174         data = tdb_fetch(tdb, key);
 175         if (!data.dptr || data.dsize != sizeof(int32)) {
 176                 SAFE_FREE(data.dptr);
 177                 return -1;
 178         }
 179
 180         ret = IVAL(data.dptr,0);
 181         SAFE_FREE(data.dptr);
 182         return ret;
 183 }
 184
 185 /****************************************************************************
 186  Fetch a int32 value by string key, return -1 if not found.
 187  Output is int32 in native byte order.
 188 ****************************************************************************/
 189
 190 int32 tdb_fetch_int32(TDB_CONTEXT *tdb, const char *keystr)
 191 {
 192         TDB_DATA key = string_term_tdb_data(keystr);
 193
 194         return tdb_fetch_int32_byblob(tdb, key);
 195 }
 196
 197 /****************************************************************************
 198  Store a int32 value by an arbitary blob key, return 0 on success, -1 on failure.
 199  Input is int32 in native byte order. Output in tdb is in little-endian.
 200 ****************************************************************************/
 201
 202 int tdb_store_int32_byblob(TDB_CONTEXT *tdb, TDB_DATA key, int32 v)
 203 {
 204         TDB_DATA data;
 205         int32 v_store;
 206
 207         SIVAL(&v_store,0,v);
 208         data.dptr = (uint8 *)&v_store;
 209         data.dsize = sizeof(int32);
 210
 211         return tdb_store(tdb, key, data, TDB_REPLACE);
 212 }
 213
 214 /****************************************************************************
 215  Store a int32 value by string key, return 0 on success, -1 on failure.
 216  Input is int32 in native byte order. Output in tdb is in little-endian.
 217 ****************************************************************************/
 218
 219 int tdb_store_int32(TDB_CONTEXT *tdb, const char *keystr, int32 v)
 220 {
 221         TDB_DATA key = string_term_tdb_data(keystr);
 222
 223         return tdb_store_int32_byblob(tdb, key, v);
 224 }
 225
 226 /****************************************************************************
 227  Fetch a uint32 value by a arbitrary blob key, return -1 if not found.
 228  Output is uint32 in native byte order.
 229 ****************************************************************************/
 230
 231 bool tdb_fetch_uint32_byblob(TDB_CONTEXT *tdb, TDB_DATA key, uint32 *value)
 232 {
 233         TDB_DATA data;
 234
 235         data = tdb_fetch(tdb, key);
 236         if (!data.dptr || data.dsize != sizeof(uint32)) {
 237                 SAFE_FREE(data.dptr);
 238                 return False;
 239         }
 240
 241         *value = IVAL(data.dptr,0);
 242         SAFE_FREE(data.dptr);
 243         return True;
 244 }
 245
 246 /****************************************************************************
 247  Fetch a uint32 value by string key, return -1 if not found.
 248  Output is uint32 in native byte order.
 249 ****************************************************************************/
 250
 251 bool tdb_fetch_uint32(TDB_CONTEXT *tdb, const char *keystr, uint32 *value)
 252 {
 253         TDB_DATA key = string_term_tdb_data(keystr);
 254
 255         return tdb_fetch_uint32_byblob(tdb, key, value);
 256 }
 257
 258 /****************************************************************************
 259  Store a uint32 value by an arbitary blob key, return 0 on success, -1 on failure.
 260  Input is uint32 in native byte order. Output in tdb is in little-endian.
 261 ****************************************************************************/
 262
 263 bool tdb_store_uint32_byblob(TDB_CONTEXT *tdb, TDB_DATA key, uint32 value)
 264 {
 265         TDB_DATA data;
 266         uint32 v_store;
 267         bool ret = True;
 268
 269         SIVAL(&v_store, 0, value);
 270         data.dptr = (uint8 *)&v_store;
 271         data.dsize = sizeof(uint32);
 272
 273         if (tdb_store(tdb, key, data, TDB_REPLACE) == -1)
 274                 ret = False;
 275
 276         return ret;
 277 }
 278
 279 /****************************************************************************
 280  Store a uint32 value by string key, return 0 on success, -1 on failure.
 281  Input is uint32 in native byte order. Output in tdb is in little-endian.
 282 ****************************************************************************/
 283
 284 bool tdb_store_uint32(TDB_CONTEXT *tdb, const char *keystr, uint32 value)
 285 {
 286         TDB_DATA key = string_term_tdb_data(keystr);
 287
 288         return tdb_store_uint32_byblob(tdb, key, value);
 289 }
 290 /****************************************************************************
 291  Store a buffer by a null terminated string key.  Return 0 on success, -1
 292  on failure.
 293 ****************************************************************************/
 294
 295 int tdb_store_bystring(TDB_CONTEXT *tdb, const char *keystr, TDB_DATA data, int flags)
 296 {
 297         TDB_DATA key = string_term_tdb_data(keystr);
 298
 299         return tdb_store(tdb, key, data, flags);
 300 }
 301
 302 int tdb_trans_store_bystring(TDB_CONTEXT *tdb, const char *keystr,
 303                              TDB_DATA data, int flags)
 304 {
 305         TDB_DATA key = string_term_tdb_data(keystr);
 306
 307         return tdb_trans_store(tdb, key, data, flags);
 308 }
 309
 310 /****************************************************************************
 311  Fetch a buffer using a null terminated string key.  Don't forget to call
 312  free() on the result dptr.
 313 ****************************************************************************/
 314
 315 TDB_DATA tdb_fetch_bystring(TDB_CONTEXT *tdb, const char *keystr)
 316 {
 317         TDB_DATA key = string_term_tdb_data(keystr);
 318
 319         return tdb_fetch(tdb, key);
 320 }
 321
 322 /****************************************************************************
 323  Delete an entry using a null terminated string key.
 324 ****************************************************************************/
 325
 326 int tdb_delete_bystring(TDB_CONTEXT *tdb, const char *keystr)
 327 {
 328         TDB_DATA key = string_term_tdb_data(keystr);
 329
 330         return tdb_delete(tdb, key);
 331 }
 332
 333 /****************************************************************************
 334  Atomic integer change. Returns old value. To create, set initial value in *oldval.
 335 ****************************************************************************/
 336
 337 int32 tdb_change_int32_atomic(TDB_CONTEXT *tdb, const char *keystr, int32 *oldval, int32 change_val)
 338 {
 339         int32 val;
 340         int32 ret = -1;
 341
 342         if (tdb_lock_bystring(tdb, keystr) == -1)
 343                 return -1;
 344
 345         if ((val = tdb_fetch_int32(tdb, keystr)) == -1) {
 346                 /* The lookup failed */
 347                 if (tdb_error(tdb) != TDB_ERR_NOEXIST) {
 348                         /* but not because it didn't exist */
 349                         goto err_out;
 350                 }
 351
 352                 /* Start with 'old' value */
 353                 val = *oldval;
 354
 355         } else {
 356                 /* It worked, set return value (oldval) to tdb data */
 357                 *oldval = val;
 358         }
 359
 360         /* Increment value for storage and return next time */
 361         val += change_val;
 362
 363         if (tdb_store_int32(tdb, keystr, val) == -1)
 364                 goto err_out;
 365
 366         ret = 0;
 367
 368   err_out:
 369
 370         tdb_unlock_bystring(tdb, keystr);
 371         return ret;
 372 }
 373
 374 /****************************************************************************
 375  Atomic unsigned integer change. Returns old value. To create, set initial value in *oldval.
 376 ****************************************************************************/
 377
 378 bool tdb_change_uint32_atomic(TDB_CONTEXT *tdb, const char *keystr, uint32 *oldval, uint32 change_val)
 379 {
 380         uint32 val;
 381         bool ret = False;
 382
 383         if (tdb_lock_bystring(tdb, keystr) == -1)
 384                 return False;
 385
 386         if (!tdb_fetch_uint32(tdb, keystr, &val)) {
 387                 /* It failed */
 388                 if (tdb_error(tdb) != TDB_ERR_NOEXIST) {
 389                         /* and not because it didn't exist */
 390                         goto err_out;
 391                 }
 392
 393                 /* Start with 'old' value */
 394                 val = *oldval;
 395
 396         } else {
 397                 /* it worked, set return value (oldval) to tdb data */
 398                 *oldval = val;
 399
 400         }
 401
 402         /* get a new value to store */
 403         val += change_val;
 404
 405         if (!tdb_store_uint32(tdb, keystr, val))
 406                 goto err_out;
 407
 408         ret = True;
 409
 410   err_out:
 411
 412         tdb_unlock_bystring(tdb, keystr);
 413         return ret;
 414 }
 415
 416 /****************************************************************************
 417  Useful pair of routines for packing/unpacking data consisting of
 418  integers and strings.
 419 ****************************************************************************/
 420
 421 size_t tdb_pack_va(uint8 *buf, int bufsize, const char *fmt, va_list ap)
 422 {
 423         uint8 bt;
 424         uint16 w;
 425         uint32 d;
 426         int i;
 427         void *p;
 428         int len;
 429         char *s;
 430         char c;
 431         uint8 *buf0 = buf;
 432         const char *fmt0 = fmt;
 433         int bufsize0 = bufsize;
 434
 435         while (*fmt) {
 436                 switch ((c = *fmt++)) {
 437                 case 'b': /* unsigned 8-bit integer */
 438                         len = 1;
 439                         bt = (uint8)va_arg(ap, int);
 440                         if (bufsize && bufsize >= len)
 441                                 SSVAL(buf, 0, bt);
 442                         break;
 443                 case 'w': /* unsigned 16-bit integer */
 444                         len = 2;
 445                         w = (uint16)va_arg(ap, int);
 446                         if (bufsize && bufsize >= len)
 447                                 SSVAL(buf, 0, w);
 448                         break;
 449                 case 'd': /* signed 32-bit integer (standard int in most systems) */
 450                         len = 4;
 451                         d = va_arg(ap, uint32);
 452                         if (bufsize && bufsize >= len)
 453                                 SIVAL(buf, 0, d);
 454                         break;
 455                 case 'p': /* pointer */
 456                         len = 4;
 457                         p = va_arg(ap, void *);
 458                         d = p?1:0;
 459                         if (bufsize && bufsize >= len)
 460                                 SIVAL(buf, 0, d);
 461                         break;
 462                 case 'P': /* null-terminated string */
 463                         s = va_arg(ap,char *);
 464                         w = strlen(s);
 465                         len = w + 1;
 466                         if (bufsize && bufsize >= len)
 467                                 memcpy(buf, s, len);
 468                         break;
 469                 case 'f': /* null-terminated string */
 470                         s = va_arg(ap,char *);
 471                         w = strlen(s);
 472                         len = w + 1;
 473                         if (bufsize && bufsize >= len)
 474                                 memcpy(buf, s, len);
 475                         break;
 476                 case 'B': /* fixed-length string */
 477                         i = va_arg(ap, int);
 478                         s = va_arg(ap, char *);
 479                         len = 4+i;
 480                         if (bufsize && bufsize >= len) {
 481                                 SIVAL(buf, 0, i);
 482                                 memcpy(buf+4, s, i);
 483                         }
 484                         break;
 485                 default:
 486                         DEBUG(0,("Unknown tdb_pack format %c in %s\n",
 487                                  c, fmt));
 488                         len = 0;
 489                         break;
 490                 }
 491
 492                 buf += len;
 493                 if (bufsize)
 494                         bufsize -= len;
 495                 if (bufsize < 0)
 496                         bufsize = 0;
 497         }
 498
 499         DEBUG(18,("tdb_pack_va(%s, %d) -> %d\n",
 500                  fmt0, bufsize0, (int)PTR_DIFF(buf, buf0)));
 501
 502         return PTR_DIFF(buf, buf0);
 503 }
 504
 505 size_t tdb_pack(uint8 *buf, int bufsize, const char *fmt, ...)
 506 {
 507         va_list ap;
 508         size_t result;
 509
 510         va_start(ap, fmt);
 511         result = tdb_pack_va(buf, bufsize, fmt, ap);
 512         va_end(ap);
 513         return result;
 514 }
 515
 516 bool tdb_pack_append(TALLOC_CTX *mem_ctx, uint8 **buf, size_t *len,
 517                      const char *fmt, ...)
 518 {
 519         va_list ap;
 520         size_t len1, len2;
 521
 522         va_start(ap, fmt);
 523         len1 = tdb_pack_va(NULL, 0, fmt, ap);
 524         va_end(ap);
 525
 526         if (mem_ctx != NULL) {
 527                 *buf = TALLOC_REALLOC_ARRAY(mem_ctx, *buf, uint8,
 528                                             (*len) + len1);
 529         } else {
 530                 *buf = SMB_REALLOC_ARRAY(*buf, uint8, (*len) + len1);
 531         }
 532
 533         if (*buf == NULL) {
 534                 return False;
 535         }
 536
 537         va_start(ap, fmt);
 538         len2 = tdb_pack_va((*buf)+(*len), len1, fmt, ap);
 539         va_end(ap);
 540
 541         if (len1 != len2) {
 542                 return False;
 543         }
 544
 545         *len += len2;
 546
 547         return True;
 548 }
 549
 550 /****************************************************************************
 551  Useful pair of routines for packing/unpacking data consisting of
 552  integers and strings.
 553 ****************************************************************************/
 554
 555 int tdb_unpack(const uint8 *buf, int bufsize, const char *fmt, ...)
 556 {
 557         va_list ap;
 558         uint8 *bt;
 559         uint16 *w;
 560         uint32 *d;
 561         int len;
 562         int *i;
 563         void **p;
 564         char *s, **b, **ps;
 565         char c;
 566         const uint8 *buf0 = buf;
 567         const char *fmt0 = fmt;
 568         int bufsize0 = bufsize;
 569
 570         va_start(ap, fmt);
 571
 572         while (*fmt) {
 573                 switch ((c=*fmt++)) {
 574                 case 'b':
 575                         len = 1;
 576                         bt = va_arg(ap, uint8 *);
 577                         if (bufsize < len)
 578                                 goto no_space;
 579                         *bt = SVAL(buf, 0);
 580                         break;
 581                 case 'w':
 582                         len = 2;
 583                         w = va_arg(ap, uint16 *);
 584                         if (bufsize < len)
 585                                 goto no_space;
 586                         *w = SVAL(buf, 0);
 587                         break;
 588                 case 'd':
 589                         len = 4;
 590                         d = va_arg(ap, uint32 *);
 591                         if (bufsize < len)
 592                                 goto no_space;
 593                         *d = IVAL(buf, 0);
 594                         break;
 595                 case 'p':
 596                         len = 4;
 597                         p = va_arg(ap, void **);
 598                         if (bufsize < len)
 599                                 goto no_space;
 600                         /*
 601                          * This isn't a real pointer - only a token (1 or 0)
 602                          * to mark the fact a pointer is present.
 603                          */
 604
 605                         *p = (void *)(IVAL(buf, 0) ? (void *)1 : NULL);
 606                         break;
 607                 case 'P':
 608                         /* Return malloc'ed string. */
 609                         ps = va_arg(ap,char **);
 610                         len = strlen((const char *)buf) + 1;
 611                         *ps = SMB_STRDUP((const char *)buf);
 612                         break;
 613                 case 'f':
 614                         s = va_arg(ap,char *);
 615                         len = strlen((const char *)buf) + 1;
 616                         if (bufsize < len || len > sizeof(fstring))
 617                                 goto no_space;
 618                         memcpy(s, buf, len);
 619                         break;
 620                 case 'B':
 621                         i = va_arg(ap, int *);
 622                         b = va_arg(ap, char **);
 623                         len = 4;
 624                         if (bufsize < len)
 625                                 goto no_space;
 626                         *i = IVAL(buf, 0);
 627                         if (! *i) {
 628                                 *b = NULL;
 629                                 break;
 630                         }
 631                         len += *i;
 632                         if (bufsize < len)
 633                                 goto no_space;
 634                         *b = (char *)SMB_MALLOC(*i);
 635                         if (! *b)
 636                                 goto no_space;
 637                         memcpy(*b, buf+4, *i);
 638                         break;
 639                 default:
 640                         DEBUG(0,("Unknown tdb_unpack format %c in %s\n",
 641                                  c, fmt));
 642
 643                         len = 0;
 644                         break;
 645                 }
 646
 647                 buf += len;
 648                 bufsize -= len;
 649         }
 650
 651         va_end(ap);
 652
 653         DEBUG(18,("tdb_unpack(%s, %d) -> %d\n",
 654                  fmt0, bufsize0, (int)PTR_DIFF(buf, buf0)));
 655
 656         return PTR_DIFF(buf, buf0);
 657
 658  no_space:
 659         return -1;
 660 }
 661
 662
 663 /****************************************************************************
 664  Log tdb messages via DEBUG().
 665 ****************************************************************************/
 666
 667 static void tdb_log(TDB_CONTEXT *tdb, enum tdb_debug_level level, const char *format, ...)
 668 {
 669         va_list ap;
 670         char *ptr = NULL;
 671
 672         va_start(ap, format);
 673         vasprintf(&ptr, format, ap);
 674         va_end(ap);
 675
 676         if (!ptr || !*ptr)
 677                 return;
 678
 679         DEBUG((int)level, ("tdb(%s): %s", tdb_name(tdb) ? tdb_name(tdb) : "unnamed", ptr));
 680         SAFE_FREE(ptr);
 681 }
 682
 683 /****************************************************************************
 684  Like tdb_open() but also setup a logging function that redirects to
 685  the samba DEBUG() system.
 686 ****************************************************************************/
 687
 688 TDB_CONTEXT *tdb_open_log(const char *name, int hash_size, int tdb_flags,
 689                           int open_flags, mode_t mode)
 690 {
 691         TDB_CONTEXT *tdb;
 692         struct tdb_logging_context log_ctx;
 693
 694         if (!lp_use_mmap())
 695                 tdb_flags |= TDB_NOMMAP;
 696
 697         log_ctx.log_fn = tdb_log;
 698         log_ctx.log_private = NULL;
 699
 700         if ((hash_size == 0) && (name != NULL)) {
 701                 const char *base = strrchr_m(name, '/');
 702                 if (base != NULL) {
 703                         base += 1;
 704                 }
 705                 else {
 706                         base = name;
 707                 }
 708                 hash_size = lp_parm_int(-1, "tdb_hashsize", base, 0);
 709         }
 710
 711         tdb = tdb_open_ex(name, hash_size, tdb_flags,
 712                           open_flags, mode, &log_ctx, NULL);
 713         if (!tdb)
 714                 return NULL;
 715
 716         return tdb;
 717 }
 718
 719 /****************************************************************************
 720  Allow tdb_delete to be used as a tdb_traversal_fn.
 721 ****************************************************************************/
 722
 723 int tdb_traverse_delete_fn(TDB_CONTEXT *the_tdb, TDB_DATA key, TDB_DATA dbuf,
 724                      void *state)
 725 {
 726     return tdb_delete(the_tdb, key);
 727 }
 728
 729
 730
 731 /**
 732  * Search across the whole tdb for keys that match the given pattern
 733  * return the result as a list of keys
 734  *
 735  * @param tdb pointer to opened tdb file context
 736  * @param pattern searching pattern used by fnmatch(3) functions
 737  *
 738  * @return list of keys found by looking up with given pattern
 739  **/
 740 TDB_LIST_NODE *tdb_search_keys(TDB_CONTEXT *tdb, const char* pattern)
 741 {
 742         TDB_DATA key, next;
 743         TDB_LIST_NODE *list = NULL;
 744         TDB_LIST_NODE *rec = NULL;
 745
 746         for (key = tdb_firstkey(tdb); key.dptr; key = next) {
 747                 /* duplicate key string to ensure null-termination */
 748                 char *key_str = SMB_STRNDUP((const char *)key.dptr, key.dsize);
 749                 if (!key_str) {
 750                         DEBUG(0, ("tdb_search_keys: strndup() failed!\n"));
 751                         smb_panic("strndup failed!\n");
 752                 }
 753
 754                 DEBUG(18, ("checking %s for match to pattern %s\n", key_str, pattern));
 755
 756                 next = tdb_nextkey(tdb, key);
 757
 758                 /* do the pattern checking */
 759                 if (fnmatch(pattern, key_str, 0) == 0) {
 760                         rec = SMB_MALLOC_P(TDB_LIST_NODE);
 761                         ZERO_STRUCTP(rec);
 762
 763                         rec->node_key = key;
 764
 765                         DLIST_ADD_END(list, rec, TDB_LIST_NODE *);
 766
 767                         DEBUG(18, ("checking %s matched pattern %s\n", key_str, pattern));
 768                 } else {
 769                         free(key.dptr);
 770                 }
 771
 772                 /* free duplicated key string */
 773                 free(key_str);
 774         }
 775
 776         return list;
 777
 778 }
 779
 780
 781 /**
 782  * Free the list returned by tdb_search_keys
 783  *
 784  * @param node list of results found by tdb_search_keys
 785  **/
 786 void tdb_search_list_free(TDB_LIST_NODE* node)
 787 {
 788         TDB_LIST_NODE *next_node;
 789
 790         while (node) {
 791                 next_node = node->next;
 792                 SAFE_FREE(node->node_key.dptr);
 793                 SAFE_FREE(node);
 794                 node = next_node;
 795         };
 796 }
 797
 798 /****************************************************************************
 799  tdb_store, wrapped in a transaction. This way we make sure that a process
 800  that dies within writing does not leave a corrupt tdb behind.
 801 ****************************************************************************/
 802
 803 int tdb_trans_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf,
 804                     int flag)
 805 {
 806         int res;
 807
 808         if ((res = tdb_transaction_start(tdb)) != 0) {
 809                 DEBUG(5, ("tdb_transaction_start failed\n"));
 810                 return res;
 811         }
 812
 813         if ((res = tdb_store(tdb, key, dbuf, flag)) != 0) {
 814                 DEBUG(10, ("tdb_store failed\n"));
 815                 if (tdb_transaction_cancel(tdb) != 0) {
 816                         smb_panic("Cancelling transaction failed");
 817                 }
 818                 return res;
 819         }
 820
 821         if ((res = tdb_transaction_commit(tdb)) != 0) {
 822                 DEBUG(5, ("tdb_transaction_commit failed\n"));
 823         }
 824
 825         return res;
 826 }
 827
 828 /****************************************************************************
 829  tdb_delete, wrapped in a transaction. This way we make sure that a process
 830  that dies within deleting does not leave a corrupt tdb behind.
 831 ****************************************************************************/
 832
 833 int tdb_trans_delete(struct tdb_context *tdb, TDB_DATA key)
 834 {
 835         int res;
 836
 837         if ((res = tdb_transaction_start(tdb)) != 0) {
 838                 DEBUG(5, ("tdb_transaction_start failed\n"));
 839                 return res;
 840         }
 841
 842         if ((res = tdb_delete(tdb, key)) != 0) {
 843                 DEBUG(10, ("tdb_delete failed\n"));
 844                 if (tdb_transaction_cancel(tdb) != 0) {
 845                         smb_panic("Cancelling transaction failed");
 846                 }
 847                 return res;
 848         }
 849
 850         if ((res = tdb_transaction_commit(tdb)) != 0) {
 851                 DEBUG(5, ("tdb_transaction_commit failed\n"));
 852         }
 853
 854         return res;
 855 }
 856
 857 /*
 858  Log tdb messages via DEBUG().
 859 */
 860 static void tdb_wrap_log(TDB_CONTEXT *tdb, enum tdb_debug_level level,
 861                          const char *format, ...) PRINTF_ATTRIBUTE(3,4);
 862
 863 static void tdb_wrap_log(TDB_CONTEXT *tdb, enum tdb_debug_level level,
 864                          const char *format, ...)
 865 {
 866         va_list ap;
 867         char *ptr = NULL;
 868         int debuglevel = 0;
 869
 870         va_start(ap, format);
 871         vasprintf(&ptr, format, ap);
 872         va_end(ap);
 873
 874         switch (level) {
 875         case TDB_DEBUG_FATAL:
 876                 debug_level = 0;
 877                 break;
 878         case TDB_DEBUG_ERROR:
 879                 debuglevel = 1;
 880                 break;
 881         case TDB_DEBUG_WARNING:
 882                 debuglevel = 2;
 883                 break;
 884         case TDB_DEBUG_TRACE:
 885                 debuglevel = 5;
 886                 break;
 887         default:
 888                 debuglevel = 0;
 889         }
 890
 891         if (ptr != NULL) {
 892                 const char *name = tdb_name(tdb);
 893                 DEBUG(debuglevel, ("tdb(%s): %s", name ? name : "unnamed", ptr));
 894                 free(ptr);
 895         }
 896 }
 897
 898 static struct tdb_wrap *tdb_list;
 899
 900 /* destroy the last connection to a tdb */
 901 static int tdb_wrap_destructor(struct tdb_wrap *w)
 902 {
 903         tdb_close(w->tdb);
 904         DLIST_REMOVE(tdb_list, w);
 905         return 0;
 906 }
 907
 908 /*
 909   wrapped connection to a tdb database
 910   to close just talloc_free() the tdb_wrap pointer
 911  */
 912 struct tdb_wrap *tdb_wrap_open(TALLOC_CTX *mem_ctx,
 913                                const char *name, int hash_size, int tdb_flags,
 914                                int open_flags, mode_t mode)
 915 {
 916         struct tdb_wrap *w;
 917         struct tdb_logging_context log_ctx;
 918         log_ctx.log_fn = tdb_wrap_log;
 919
 920         if (!lp_use_mmap())
 921                 tdb_flags |= TDB_NOMMAP;
 922
 923         for (w=tdb_list;w;w=w->next) {
 924                 if (strcmp(name, w->name) == 0) {
 925                         /*
 926                          * Yes, talloc_reference is exactly what we want
 927                          * here. Otherwise we would have to implement our own
 928                          * reference counting.
 929                          */
 930                         return talloc_reference(mem_ctx, w);
 931                 }
 932         }
 933
 934         w = talloc(mem_ctx, struct tdb_wrap);
 935         if (w == NULL) {
 936                 return NULL;
 937         }
 938
 939         if (!(w->name = talloc_strdup(w, name))) {
 940                 talloc_free(w);
 941                 return NULL;
 942         }
 943
 944         if ((hash_size == 0) && (name != NULL)) {
 945                 const char *base = strrchr_m(name, '/');
 946                 if (base != NULL) {
 947                         base += 1;
 948                 }
 949                 else {
 950                         base = name;
 951                 }
 952                 hash_size = lp_parm_int(-1, "tdb_hashsize", base, 0);
 953         }
 954
 955         w->tdb = tdb_open_ex(name, hash_size, tdb_flags,
 956                              open_flags, mode, &log_ctx, NULL);
 957         if (w->tdb == NULL) {
 958                 talloc_free(w);
 959                 return NULL;
 960         }
 961
 962         talloc_set_destructor(w, tdb_wrap_destructor);
 963
 964         DLIST_ADD(tdb_list, w);
 965
 966         return w;
 967 }
 968
 969 NTSTATUS map_nt_error_from_tdb(enum TDB_ERROR err)
 970 {
 971         struct { enum TDB_ERROR err; NTSTATUS status; } map[] =
 972                 { { TDB_SUCCESS,        NT_STATUS_OK },
 973                   { TDB_ERR_CORRUPT,    NT_STATUS_INTERNAL_DB_CORRUPTION },
 974                   { TDB_ERR_IO,         NT_STATUS_UNEXPECTED_IO_ERROR },
 975                   { TDB_ERR_OOM,        NT_STATUS_NO_MEMORY },
 976                   { TDB_ERR_EXISTS,     NT_STATUS_OBJECT_NAME_COLLISION },
 977
 978                   /*
 979                    * TDB_ERR_LOCK is very broad, we could for example
 980                    * distinguish between fcntl locks and invalid lock
 981                    * sequences. So NT_STATUS_FILE_LOCK_CONFLICT is a
 982                    * compromise.
 983                    */
 984                   { TDB_ERR_LOCK,       NT_STATUS_FILE_LOCK_CONFLICT },
 985                   /*
 986                    * The next two ones in the enum are not actually used
 987                    */
 988                   { TDB_ERR_NOLOCK,     NT_STATUS_FILE_LOCK_CONFLICT },
 989                   { TDB_ERR_LOCK_TIMEOUT, NT_STATUS_FILE_LOCK_CONFLICT },
 990                   { TDB_ERR_NOEXIST,    NT_STATUS_NOT_FOUND },
 991                   { TDB_ERR_EINVAL,     NT_STATUS_INVALID_PARAMETER },
 992                   { TDB_ERR_RDONLY,     NT_STATUS_ACCESS_DENIED }
 993                 };
 994
 995         int i;
 996
 997         for (i=0; i < sizeof(map) / sizeof(map[0]); i++) {
 998                 if (err == map[i].err) {
 999                         return map[i].status;
1000                 }
1001         }
1002
1003         return NT_STATUS_INTERNAL_ERROR;
1004 }
1005
1006
1007 /*********************************************************************
1008  * the following is a generic validation mechanism for tdbs.
1009  *********************************************************************/
1010
1011 /*
1012  * internal validation function, executed by the child.
1013  */
1014 static int tdb_validate_child(struct tdb_context *tdb,
1015                               tdb_validate_data_func validate_fn)
1016 {
1017         int ret = 1;
1018         int num_entries = 0;
1019         struct tdb_validation_status v_status;
1020
1021         v_status.tdb_error = False;
1022         v_status.bad_freelist = False;
1023         v_status.bad_entry = False;
1024         v_status.unknown_key = False;
1025         v_status.success = True;
1026
1027         if (!tdb) {
1028                 v_status.tdb_error = True;
1029                 v_status.success = False;
1030                 goto out;
1031         }
1032
1033         /* Check if the tdb's freelist is good. */
1034         if (tdb_validate_freelist(tdb, &num_entries) == -1) {
1035                 v_status.bad_freelist = True;
1036                 v_status.success = False;
1037                 goto out;
1038         }
1039
1040         DEBUG(10,("tdb_validate_child: tdb %s freelist has %d entries\n",
1041                   tdb_name(tdb), num_entries));
1042
1043         /* Now traverse the tdb to validate it. */
1044         num_entries = tdb_traverse(tdb, validate_fn, (void *)&v_status);
1045         if (!v_status.success) {
1046                 goto out;
1047         } else if (num_entries == -1) {
1048                 v_status.tdb_error = True;
1049                 v_status.success = False;
1050                 goto out;
1051         }
1052
1053         DEBUG(10,("tdb_validate_child: tdb %s is good with %d entries\n",
1054                   tdb_name(tdb), num_entries));
1055         ret = 0; /* Cache is good. */
1056
1057 out:
1058         DEBUG(10,   ("tdb_validate_child: summary of validation status:\n"));
1059         DEBUGADD(10,(" * tdb error: %s\n", v_status.tdb_error ? "yes" : "no"));
1060         DEBUGADD(10,(" * bad freelist: %s\n",v_status.bad_freelist?"yes":"no"));
1061         DEBUGADD(10,(" * bad entry: %s\n", v_status.bad_entry ? "yes" : "no"));
1062         DEBUGADD(10,(" * unknown key: %s\n", v_status.unknown_key?"yes":"no"));
1063         DEBUGADD(10,(" => overall success: %s\n", v_status.success?"yes":"no"));
1064
1065         return ret;
1066 }
1067
1068 /*
1069  * tdb validation function.
1070  * returns 0 if tdb is ok, != 0 if it isn't.
1071  * this function expects an opened tdb.
1072  */
1073 int tdb_validate(struct tdb_context *tdb, tdb_validate_data_func validate_fn)
1074 {
1075         pid_t child_pid = -1;
1076         int child_status = 0;
1077         int wait_pid = 0;
1078         int ret = 1;
1079
1080         if (tdb == NULL) {
1081                 DEBUG(1, ("Error: tdb_validate called with tdb == NULL\n"));
1082                 return ret;
1083         }
1084
1085         DEBUG(5, ("tdb_validate called for tdb '%s'\n", tdb_name(tdb)));
1086
1087         /* fork and let the child do the validation.
1088          * benefit: no need to twist signal handlers and panic functions.
1089          * just let the child panic. we catch the signal. */
1090
1091         DEBUG(10, ("tdb_validate: forking to let child do validation.\n"));
1092         child_pid = sys_fork();
1093         if (child_pid == 0) {
1094                 /* child code */
1095                 DEBUG(10, ("tdb_validate (validation child): created\n"));
1096                 DEBUG(10, ("tdb_validate (validation child): "
1097                            "calling tdb_validate_child\n"));
1098                 exit(tdb_validate_child(tdb, validate_fn));
1099         }
1100         else if (child_pid < 0) {
1101                 DEBUG(1, ("tdb_validate: fork for validation failed.\n"));
1102                 goto done;
1103         }
1104
1105         /* parent */
1106
1107         DEBUG(10, ("tdb_validate: fork succeeded, child PID = %d\n",child_pid));
1108
1109         DEBUG(10, ("tdb_validate: waiting for child to finish...\n"));
1110         while  ((wait_pid = sys_waitpid(child_pid, &child_status, 0)) < 0) {
1111                 if (errno == EINTR) {
1112                         DEBUG(10, ("tdb_validate: got signal during waitpid, "
1113                                    "retrying\n"));
1114                         errno = 0;
1115                         continue;
1116                 }
1117                 DEBUG(1, ("tdb_validate: waitpid failed with error '%s'.\n",
1118                           strerror(errno)));
1119                 goto done;
1120         }
1121         if (wait_pid != child_pid) {
1122                 DEBUG(1, ("tdb_validate: waitpid returned pid %d, "
1123                           "but %d was expected\n", wait_pid, child_pid));
1124                 goto done;
1125         }
1126
1127         DEBUG(10, ("tdb_validate: validating child returned.\n"));
1128         if (WIFEXITED(child_status)) {
1129                 DEBUG(10, ("tdb_validate: child exited, code %d.\n",
1130                            WEXITSTATUS(child_status)));
1131                 ret = WEXITSTATUS(child_status);
1132         }
1133         if (WIFSIGNALED(child_status)) {
1134                 DEBUG(10, ("tdb_validate: child terminated by signal %d\n",
1135                            WTERMSIG(child_status)));
1136 #ifdef WCOREDUMP
1137                 if (WCOREDUMP(child_status)) {
1138                         DEBUGADD(10, ("core dumped\n"));
1139                 }
1140 #endif
1141                 ret = WTERMSIG(child_status);
1142         }
1143         if (WIFSTOPPED(child_status)) {
1144                 DEBUG(10, ("tdb_validate: child was stopped by signal %d\n",
1145                            WSTOPSIG(child_status)));
1146                 ret = WSTOPSIG(child_status);
1147         }
1148
1149 done:
1150         DEBUG(5, ("tdb_validate returning code '%d' for tdb '%s'\n", ret,
1151                   tdb_name(tdb)));
1152
1153         return ret;
1154 }
1155
1156 /*
1157  * tdb validation function.
1158  * returns 0 if tdb is ok, != 0 if it isn't.
1159  * this is a wrapper around the actual validation function that opens and closes
1160  * the tdb.
1161  */
1162 int tdb_validate_open(const char *tdb_path, tdb_validate_data_func validate_fn)
1163 {
1164         TDB_CONTEXT *tdb = NULL;
1165         int ret = 1;
1166
1167         DEBUG(5, ("tdb_validate_open called for tdb '%s'\n", tdb_path));
1168
1169         tdb = tdb_open_log(tdb_path, 0, TDB_DEFAULT, O_RDONLY, 0);
1170         if (!tdb) {
1171                 DEBUG(1, ("Error opening tdb %s\n", tdb_path));
1172                 return ret;
1173         }
1174
1175         ret = tdb_validate(tdb, validate_fn);
1176         tdb_close(tdb);
1177         return ret;
1178 }
1179
1180 /*
1181  * tdb backup function and helpers for tdb_validate wrapper with backup
1182  * handling.
1183  */
1184
1185 /* this structure eliminates the need for a global overall status for
1186  * the traverse-copy */
1187 struct tdb_copy_data {
1188         struct tdb_context *dst;
1189         bool success;
1190 };
1191
1192 static int traverse_copy_fn(struct tdb_context *tdb, TDB_DATA key,
1193                             TDB_DATA dbuf, void *private_data)
1194 {
1195         struct tdb_copy_data *data = (struct tdb_copy_data *)private_data;
1196
1197         if (tdb_store(data->dst, key, dbuf, TDB_INSERT) != 0) {
1198                 DEBUG(4, ("Failed to insert into %s: %s\n", tdb_name(data->dst),
1199                           strerror(errno)));
1200                 data->success = False;
1201                 return 1;
1202         }
1203         return 0;
1204 }
1205
1206 static int tdb_copy(struct tdb_context *src, struct tdb_context *dst)
1207 {
1208         struct tdb_copy_data data;
1209         int count;
1210
1211         data.dst = dst;
1212         data.success = True;
1213
1214         count = tdb_traverse(src, traverse_copy_fn, (void *)(&data));
1215         if ((count < 0) || (data.success == False)) {
1216                 return -1;
1217         }
1218         return count;
1219 }
1220
1221 static int tdb_verify_basic(struct tdb_context *tdb)
1222 {
1223         return tdb_traverse(tdb, NULL, NULL);
1224 }
1225
1226 /* this backup function is essentially taken from lib/tdb/tools/tdbbackup.tdb
1227  */
1228 static int tdb_backup(TALLOC_CTX *ctx, const char *src_path,
1229                       const char *dst_path, int hash_size)
1230 {
1231         struct tdb_context *src_tdb = NULL;
1232         struct tdb_context *dst_tdb = NULL;
1233         char *tmp_path = NULL;
1234         struct stat st;
1235         int count1, count2;
1236         int saved_errno = 0;
1237         int ret = -1;
1238
1239         if (stat(src_path, &st) != 0) {
1240                 DEBUG(3, ("Could not stat '%s': %s\n", src_path,
1241                           strerror(errno)));
1242                 goto done;
1243         }
1244
1245         /* open old tdb RDWR - so we can lock it */
1246         src_tdb = tdb_open_log(src_path, 0, TDB_DEFAULT, O_RDWR, 0);
1247         if (src_tdb == NULL) {
1248                 DEBUG(3, ("Failed to open tdb '%s'\n", src_path));
1249                 goto done;
1250         }
1251
1252         if (tdb_lockall(src_tdb) != 0) {
1253                 DEBUG(3, ("Failed to lock tdb '%s'\n", src_path));
1254                 goto done;
1255         }
1256
1257         tmp_path = talloc_asprintf(ctx, "%s%s", dst_path, ".tmp");
1258         unlink(tmp_path);
1259         dst_tdb = tdb_open_log(tmp_path,
1260                                hash_size ? hash_size : tdb_hash_size(src_tdb),
1261                                TDB_DEFAULT, O_RDWR | O_CREAT | O_EXCL,
1262                                st.st_mode & 0777);
1263         if (dst_tdb == NULL) {
1264                 DEBUG(3, ("Error creating tdb '%s': %s\n", tmp_path,
1265                           strerror(errno)));
1266                 saved_errno = errno;
1267                 unlink(tmp_path);
1268                 goto done;
1269         }
1270
1271         count1 = tdb_copy(src_tdb, dst_tdb);
1272         if (count1 < 0) {
1273                 DEBUG(3, ("Failed to copy tdb '%s': %s\n", src_path,
1274                           strerror(errno)));
1275                 tdb_close(dst_tdb);
1276                 goto done;
1277         }
1278
1279         /* reopen ro and do basic verification */
1280         tdb_close(dst_tdb);
1281         dst_tdb = tdb_open_log(tmp_path, 0, TDB_DEFAULT, O_RDONLY, 0);
1282         if (!dst_tdb) {
1283                 DEBUG(3, ("Failed to reopen tdb '%s': %s\n", tmp_path,
1284                           strerror(errno)));
1285                 goto done;
1286         }
1287         count2 = tdb_verify_basic(dst_tdb);
1288         if (count2 != count1) {
1289                 DEBUG(3, ("Failed to verify result of copying tdb '%s'.\n",
1290                           src_path));
1291                 tdb_close(dst_tdb);
1292                 goto done;
1293         }
1294
1295         DEBUG(10, ("tdb_backup: successfully copied %d entries\n", count1));
1296
1297         /* make sure the new tdb has reached stable storage
1298          * then rename it to its destination */
1299         fsync(tdb_fd(dst_tdb));
1300         tdb_close(dst_tdb);
1301         unlink(dst_path);
1302         if (rename(tmp_path, dst_path) != 0) {
1303                 DEBUG(3, ("Failed to rename '%s' to '%s': %s\n",
1304                           tmp_path, dst_path, strerror(errno)));
1305                 goto done;
1306         }
1307
1308         /* success */
1309         ret = 0;
1310
1311 done:
1312         if (src_tdb != NULL) {
1313                 tdb_close(src_tdb);
1314         }
1315         if (tmp_path != NULL) {
1316                 unlink(tmp_path);
1317                 TALLOC_FREE(tmp_path);
1318         }
1319         if (saved_errno != 0) {
1320                 errno = saved_errno;
1321         }
1322         return ret;
1323 }
1324
1325 static int rename_file_with_suffix(TALLOC_CTX *ctx, const char *path,
1326                                    const char *suffix)
1327 {
1328         int ret = -1;
1329         char *dst_path;
1330
1331         dst_path = talloc_asprintf(ctx, "%s%s", path, suffix);
1332
1333         ret = (rename(path, dst_path) != 0);
1334
1335         if (ret == 0) {
1336                 DEBUG(5, ("moved '%s' to '%s'\n", path, dst_path));
1337         } else if (errno == ENOENT) {
1338                 DEBUG(3, ("file '%s' does not exist - so not moved\n", path));
1339                 ret = 0;
1340         } else {
1341                 DEBUG(3, ("error renaming %s to %s: %s\n", path, dst_path,
1342                           strerror(errno)));
1343         }
1344
1345         TALLOC_FREE(dst_path);
1346         return ret;
1347 }
1348
1349 /*
1350  * do a backup of a tdb, moving the destination out of the way first
1351  */
1352 static int tdb_backup_with_rotate(TALLOC_CTX *ctx, const char *src_path,
1353                                   const char *dst_path, int hash_size,
1354                                   const char *rotate_suffix,
1355                                   bool retry_norotate_if_nospc,
1356                                   bool rename_as_last_resort_if_nospc)
1357 {
1358         int ret;
1359
1360         rename_file_with_suffix(ctx, dst_path, rotate_suffix);
1361
1362         ret = tdb_backup(ctx, src_path, dst_path, hash_size);
1363
1364         if (ret != 0) {
1365                 DEBUG(10, ("backup of %s failed: %s\n", src_path, strerror(errno)));
1366         }
1367         if ((ret != 0) && (errno == ENOSPC) && retry_norotate_if_nospc)
1368         {
1369                 char *rotate_path = talloc_asprintf(ctx, "%s%s", dst_path,
1370                                                     rotate_suffix);
1371                 DEBUG(10, ("backup of %s failed due to lack of space\n",
1372                            src_path));
1373                 DEBUGADD(10, ("trying to free some space by removing rotated "
1374                               "dst %s\n", rotate_path));
1375                 if (unlink(rotate_path) == -1) {
1376                         DEBUG(10, ("unlink of %s failed: %s\n", rotate_path,
1377                                    strerror(errno)));
1378                 } else {
1379                         ret = tdb_backup(ctx, src_path, dst_path, hash_size);
1380                 }
1381                 TALLOC_FREE(rotate_path);
1382         }
1383
1384         if ((ret != 0) && (errno == ENOSPC) && rename_as_last_resort_if_nospc)
1385         {
1386                 DEBUG(10, ("backup of %s failed due to lack of space\n",
1387                            src_path));
1388                 DEBUGADD(10, ("using 'rename' as a last resort\n"));
1389                 ret = rename(src_path, dst_path);
1390         }
1391
1392         return ret;
1393 }
1394
1395 /*
1396  * validation function with backup handling:
1397  *
1398  *  - calls tdb_validate
1399  *  - if the tdb is ok, create a backup "name.bak", possibly moving
1400  *    existing backup to name.bak.old,
1401  *    return 0 (success) even if the backup fails
1402  *  - if the tdb is corrupt:
1403  *    - move the tdb to "name.corrupt"
1404  *    - check if there is valid backup.
1405  *      if so, restore the backup.
1406  *      if restore is successful, return 0 (success),
1407  *    - otherwise return -1 (failure)
1408  */
1409 int tdb_validate_and_backup(const char *tdb_path,
1410                             tdb_validate_data_func validate_fn)
1411 {
1412         int ret = -1;
1413         const char *backup_suffix = ".bak";
1414         const char *corrupt_suffix = ".corrupt";
1415         const char *rotate_suffix = ".old";
1416         char *tdb_path_backup;
1417         struct stat st;
1418         TALLOC_CTX *ctx = NULL;
1419
1420         ctx = talloc_new(NULL);
1421         if (ctx == NULL) {
1422                 DEBUG(0, ("tdb_validate_and_backup: out of memory\n"));
1423                 goto done;
1424         }
1425
1426         tdb_path_backup = talloc_asprintf(ctx, "%s%s", tdb_path, backup_suffix);
1427
1428         ret = tdb_validate_open(tdb_path, validate_fn);
1429
1430         if (ret == 0) {
1431                 DEBUG(1, ("tdb '%s' is valid\n", tdb_path));
1432                 ret = tdb_backup_with_rotate(ctx, tdb_path, tdb_path_backup, 0,
1433                                              rotate_suffix, True, False);
1434                 if (ret != 0) {
1435                         DEBUG(1, ("Error creating backup of tdb '%s'\n",
1436                                   tdb_path));
1437                         /* the actual validation was successful: */
1438                         ret = 0;
1439                 } else {
1440                         DEBUG(1, ("Created backup '%s' of tdb '%s'\n",
1441                                   tdb_path_backup, tdb_path));
1442                 }
1443         } else {
1444                 DEBUG(1, ("tdb '%s' is invalid\n", tdb_path));
1445
1446                 ret =stat(tdb_path_backup, &st);
1447                 if (ret != 0) {
1448                         DEBUG(5, ("Could not stat '%s': %s\n", tdb_path_backup,
1449                                   strerror(errno)));
1450                         DEBUG(1, ("No backup found.\n"));
1451                 } else {
1452                         DEBUG(1, ("backup '%s' found.\n", tdb_path_backup));
1453                         ret = tdb_validate_open(tdb_path_backup, validate_fn);
1454                         if (ret != 0) {
1455                                 DEBUG(1, ("Backup '%s' is invalid.\n",
1456                                           tdb_path_backup));
1457                         }
1458                 }
1459
1460                 if (ret != 0) {
1461                         int renamed = rename_file_with_suffix(ctx, tdb_path,
1462                                                               corrupt_suffix);
1463                         if (renamed != 0) {
1464                                 DEBUG(1, ("Error moving tdb to '%s%s'\n",
1465                                           tdb_path, corrupt_suffix));
1466                         } else {
1467                                 DEBUG(1, ("Corrupt tdb stored as '%s%s'\n",
1468                                           tdb_path, corrupt_suffix));
1469                         }
1470                         goto done;
1471                 }
1472
1473                 DEBUG(1, ("valid backup '%s' found\n", tdb_path_backup));
1474                 ret = tdb_backup_with_rotate(ctx, tdb_path_backup, tdb_path, 0,
1475                                              corrupt_suffix, True, True);
1476                 if (ret != 0) {
1477                         DEBUG(1, ("Error restoring backup from '%s'\n",
1478                                   tdb_path_backup));
1479                 } else {
1480                         DEBUG(1, ("Restored tdb backup from '%s'\n",
1481                                   tdb_path_backup));
1482                 }
1483         }
1484
1485 done:
1486         TALLOC_FREE(ctx);
1487         return ret;
1488 }