source3/locking/locking.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Locking functions
   4    Copyright (C) Andrew Tridgell 1992-2000
   5    Copyright (C) Jeremy Allison 1992-2006
   6    Copyright (C) Volker Lendecke 2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22    Revision History:
  23
  24    12 aug 96: Erik.Devriendt@te6.siemens.be
  25    added support for shared memory implementation of share mode locking
  26
  27    May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
  28    locking to deal with multiple share modes per open file.
  29
  30    September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
  31    support.
  32
  33    rewrtten completely to use new tdb code. Tridge, Dec '99
  34
  35    Added POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
  36    Added Unix Extensions POSIX locking support. Jeremy Allison Mar 2006.
  37 */
  38
  39 #include "includes.h"
  40
  41 #undef DBGC_CLASS
  42 #define DBGC_CLASS DBGC_LOCKING
  43
  44 /* the locking database handle */
  45 static TDB_CONTEXT *tdb;
  46
  47 /****************************************************************************
  48  Debugging aids :-).
  49 ****************************************************************************/
  50
  51 const char *lock_type_name(enum brl_type lock_type)
  52 {
  53         switch (lock_type) {
  54                 case READ_LOCK:
  55                         return "READ";
  56                 case WRITE_LOCK:
  57                         return "WRITE";
  58                 case PENDING_LOCK:
  59                         return "PENDING";
  60                 default:
  61                         return "other";
  62         }
  63 }
  64
  65 const char *lock_flav_name(enum brl_flavour lock_flav)
  66 {
  67         return (lock_flav == WINDOWS_LOCK) ? "WINDOWS_LOCK" : "POSIX_LOCK";
  68 }
  69
  70 /****************************************************************************
  71  Utility function called to see if a file region is locked.
  72  Called in the read/write codepath.
  73 ****************************************************************************/
  74
  75 BOOL is_locked(files_struct *fsp,
  76                 uint32 smbpid,
  77                 SMB_BIG_UINT count,
  78                 SMB_BIG_UINT offset,
  79                 enum brl_type lock_type)
  80 {
  81         int snum = SNUM(fsp->conn);
  82         int strict_locking = lp_strict_locking(snum);
  83         enum brl_flavour lock_flav = lp_posix_cifsu_locktype();
  84         BOOL ret = True;
  85
  86         if (count == 0) {
  87                 return False;
  88         }
  89
  90         if (!lp_locking(snum) || !strict_locking) {
  91                 return False;
  92         }
  93
  94         if (strict_locking == Auto) {
  95                 if  (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && (lock_type == READ_LOCK || lock_type == WRITE_LOCK)) {
  96                         DEBUG(10,("is_locked: optimisation - exclusive oplock on file %s\n", fsp->fsp_name ));
  97                         ret = False;
  98                 } else if ((fsp->oplock_type == LEVEL_II_OPLOCK) &&
  99                            (lock_type == READ_LOCK)) {
 100                         DEBUG(10,("is_locked: optimisation - level II oplock on file %s\n", fsp->fsp_name ));
 101                         ret = False;
 102                 } else {
 103                         struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 104                         if (!br_lck) {
 105                                 return False;
 106                         }
 107                         ret = !brl_locktest(br_lck,
 108                                         smbpid,
 109                                         procid_self(),
 110                                         offset,
 111                                         count,
 112                                         lock_type,
 113                                         lock_flav);
 114                         TALLOC_FREE(br_lck);
 115                 }
 116         } else {
 117                 struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 118                 if (!br_lck) {
 119                         return False;
 120                 }
 121                 ret = !brl_locktest(br_lck,
 122                                 smbpid,
 123                                 procid_self(),
 124                                 offset,
 125                                 count,
 126                                 lock_type,
 127                                 lock_flav);
 128                 TALLOC_FREE(br_lck);
 129         }
 130
 131         DEBUG(10,("is_locked: flavour = %s brl start=%.0f len=%.0f %s for fnum %d file %s\n",
 132                         lock_flav_name(lock_flav),
 133                         (double)offset, (double)count, ret ? "locked" : "unlocked",
 134                         fsp->fnum, fsp->fsp_name ));
 135
 136         return ret;
 137 }
 138
 139 /****************************************************************************
 140  Find out if a lock could be granted - return who is blocking us if we can't.
 141 ****************************************************************************/
 142
 143 NTSTATUS query_lock(files_struct *fsp,
 144                         uint32 *psmbpid,
 145                         SMB_BIG_UINT *pcount,
 146                         SMB_BIG_UINT *poffset,
 147                         enum brl_type *plock_type,
 148                         enum brl_flavour lock_flav)
 149 {
 150         struct byte_range_lock *br_lck = NULL;
 151         NTSTATUS status = NT_STATUS_LOCK_NOT_GRANTED;
 152
 153         if (!fsp->can_lock) {
 154                 return fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
 155         }
 156
 157         if (!lp_locking(SNUM(fsp->conn))) {
 158                 return NT_STATUS_OK;
 159         }
 160
 161         br_lck = brl_get_locks(NULL, fsp);
 162         if (!br_lck) {
 163                 return NT_STATUS_NO_MEMORY;
 164         }
 165
 166         status = brl_lockquery(br_lck,
 167                         psmbpid,
 168                         procid_self(),
 169                         poffset,
 170                         pcount,
 171                         plock_type,
 172                         lock_flav);
 173
 174         TALLOC_FREE(br_lck);
 175         return status;
 176 }
 177
 178 /****************************************************************************
 179  Utility function called by locking requests.
 180 ****************************************************************************/
 181
 182 struct byte_range_lock *do_lock(files_struct *fsp,
 183                         uint32 lock_pid,
 184                         SMB_BIG_UINT count,
 185                         SMB_BIG_UINT offset,
 186                         enum brl_type lock_type,
 187                         enum brl_flavour lock_flav,
 188                         BOOL blocking_lock,
 189                         NTSTATUS *perr)
 190 {
 191         struct byte_range_lock *br_lck = NULL;
 192
 193         if (!fsp->can_lock) {
 194                 *perr = fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
 195                 return NULL;
 196         }
 197
 198         if (!lp_locking(SNUM(fsp->conn))) {
 199                 *perr = NT_STATUS_OK;
 200                 return NULL;
 201         }
 202
 203         /* NOTE! 0 byte long ranges ARE allowed and should be stored  */
 204
 205         DEBUG(10,("do_lock: lock flavour %s lock type %s start=%.0f len=%.0f requested for fnum %d file %s\n",
 206                 lock_flav_name(lock_flav), lock_type_name(lock_type),
 207                 (double)offset, (double)count, fsp->fnum, fsp->fsp_name ));
 208
 209         br_lck = brl_get_locks(NULL, fsp);
 210         if (!br_lck) {
 211                 *perr = NT_STATUS_NO_MEMORY;
 212                 return NULL;
 213         }
 214
 215         *perr = brl_lock(br_lck,
 216                         lock_pid,
 217                         procid_self(),
 218                         offset,
 219                         count,
 220                         lock_type,
 221                         lock_flav,
 222                         blocking_lock);
 223
 224         return br_lck;
 225 }
 226
 227 /****************************************************************************
 228  Utility function called by unlocking requests.
 229 ****************************************************************************/
 230
 231 NTSTATUS do_unlock(files_struct *fsp,
 232                         uint32 lock_pid,
 233                         SMB_BIG_UINT count,
 234                         SMB_BIG_UINT offset,
 235                         enum brl_flavour lock_flav)
 236 {
 237         BOOL ok = False;
 238         struct byte_range_lock *br_lck = NULL;
 239
 240         if (!fsp->can_lock) {
 241                 return fsp->is_directory ? NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
 242         }
 243
 244         if (!lp_locking(SNUM(fsp->conn))) {
 245                 return NT_STATUS_OK;
 246         }
 247
 248         DEBUG(10,("do_unlock: unlock start=%.0f len=%.0f requested for fnum %d file %s\n",
 249                   (double)offset, (double)count, fsp->fnum, fsp->fsp_name ));
 250
 251         br_lck = brl_get_locks(NULL, fsp);
 252         if (!br_lck) {
 253                 return NT_STATUS_NO_MEMORY;
 254         }
 255
 256         ok = brl_unlock(br_lck,
 257                         lock_pid,
 258                         procid_self(),
 259                         offset,
 260                         count,
 261                         lock_flav);
 262
 263         TALLOC_FREE(br_lck);
 264
 265         if (!ok) {
 266                 DEBUG(10,("do_unlock: returning ERRlock.\n" ));
 267                 return NT_STATUS_RANGE_NOT_LOCKED;
 268         }
 269
 270         return NT_STATUS_OK;
 271 }
 272
 273 /****************************************************************************
 274  Cancel any pending blocked locks.
 275 ****************************************************************************/
 276
 277 NTSTATUS do_lock_cancel(files_struct *fsp,
 278                         uint32 lock_pid,
 279                         SMB_BIG_UINT count,
 280                         SMB_BIG_UINT offset,
 281                         enum brl_flavour lock_flav)
 282 {
 283         BOOL ok = False;
 284         struct byte_range_lock *br_lck = NULL;
 285
 286         if (!fsp->can_lock) {
 287                 return fsp->is_directory ?
 288                         NT_STATUS_INVALID_DEVICE_REQUEST : NT_STATUS_INVALID_HANDLE;
 289         }
 290
 291         if (!lp_locking(SNUM(fsp->conn))) {
 292                 return NT_STATUS_DOS(ERRDOS, ERRcancelviolation);
 293         }
 294
 295         DEBUG(10,("do_lock_cancel: cancel start=%.0f len=%.0f requested for fnum %d file %s\n",
 296                   (double)offset, (double)count, fsp->fnum, fsp->fsp_name ));
 297
 298         br_lck = brl_get_locks(NULL, fsp);
 299         if (!br_lck) {
 300                 return NT_STATUS_NO_MEMORY;
 301         }
 302
 303         ok = brl_lock_cancel(br_lck,
 304                         lock_pid,
 305                         procid_self(),
 306                         offset,
 307                         count,
 308                         lock_flav);
 309
 310         TALLOC_FREE(br_lck);
 311
 312         if (!ok) {
 313                 DEBUG(10,("do_lock_cancel: returning ERRcancelviolation.\n" ));
 314                 return NT_STATUS_DOS(ERRDOS, ERRcancelviolation);
 315         }
 316
 317         return NT_STATUS_OK;
 318 }
 319
 320 /****************************************************************************
 321  Remove any locks on this fd. Called from file_close().
 322 ****************************************************************************/
 323
 324 void locking_close_file(files_struct *fsp)
 325 {
 326         struct byte_range_lock *br_lck;
 327
 328         if (!lp_locking(SNUM(fsp->conn))) {
 329                 return;
 330         }
 331
 332         br_lck = brl_get_locks(NULL,fsp);
 333
 334         if (br_lck) {
 335                 cancel_pending_lock_requests_by_fid(fsp, br_lck);
 336                 brl_close_fnum(br_lck);
 337                 TALLOC_FREE(br_lck);
 338         }
 339 }
 340
 341 /****************************************************************************
 342  Initialise the locking functions.
 343 ****************************************************************************/
 344
 345 static int open_read_only;
 346
 347 BOOL locking_init(int read_only)
 348 {
 349         brl_init(read_only);
 350
 351         if (tdb)
 352                 return True;
 353
 354         tdb = tdb_open_log(lock_path("locking.tdb"),
 355                         lp_open_files_db_hash_size(),
 356                         TDB_DEFAULT|(read_only?0x0:TDB_CLEAR_IF_FIRST),
 357                         read_only?O_RDONLY:O_RDWR|O_CREAT,
 358                         0644);
 359
 360         if (!tdb) {
 361                 DEBUG(0,("ERROR: Failed to initialise locking database\n"));
 362                 return False;
 363         }
 364
 365         if (!posix_locking_init(read_only))
 366                 return False;
 367
 368         open_read_only = read_only;
 369
 370         return True;
 371 }
 372
 373 /*******************************************************************
 374  Deinitialize the share_mode management.
 375 ******************************************************************/
 376
 377 BOOL locking_end(void)
 378 {
 379         BOOL ret = True;
 380
 381         brl_shutdown(open_read_only);
 382         if (tdb) {
 383                 if (tdb_close(tdb) != 0)
 384                         ret = False;
 385         }
 386
 387         return ret;
 388 }
 389
 390 /*******************************************************************
 391  Form a static locking key for a dev/inode pair.
 392 ******************************************************************/
 393
 394 /* key and data records in the tdb locking database */
 395 struct locking_key {
 396         SMB_DEV_T dev;
 397         SMB_INO_T ino;
 398 };
 399
 400 /*******************************************************************
 401  Form a static locking key for a dev/inode pair.
 402 ******************************************************************/
 403
 404 static TDB_DATA locking_key(SMB_DEV_T dev, SMB_INO_T inode)
 405 {
 406         static struct locking_key key;
 407         TDB_DATA kbuf;
 408
 409         memset(&key, '\0', sizeof(key));
 410         key.dev = dev;
 411         key.ino = inode;
 412         kbuf.dptr = (char *)&key;
 413         kbuf.dsize = sizeof(key);
 414         return kbuf;
 415 }
 416
 417 /*******************************************************************
 418  Print out a share mode.
 419 ********************************************************************/
 420
 421 char *share_mode_str(int num, struct share_mode_entry *e)
 422 {
 423         static pstring share_str;
 424
 425         slprintf(share_str, sizeof(share_str)-1, "share_mode_entry[%d]: %s "
 426                  "pid = %s, share_access = 0x%x, private_options = 0x%x, "
 427                  "access_mask = 0x%x, mid = 0x%x, type= 0x%x, file_id = %lu, "
 428                  "uid = %u, dev = 0x%x, inode = %.0f",
 429                  num,
 430                  e->op_type == UNUSED_SHARE_MODE_ENTRY ? "UNUSED" : "",
 431                  procid_str_static(&e->pid),
 432                  e->share_access, e->private_options,
 433                  e->access_mask, e->op_mid, e->op_type, e->share_file_id,
 434                  (unsigned int)e->uid, (unsigned int)e->dev, (double)e->inode );
 435
 436         return share_str;
 437 }
 438
 439 /*******************************************************************
 440  Print out a share mode table.
 441 ********************************************************************/
 442
 443 static void print_share_mode_table(struct locking_data *data)
 444 {
 445         int num_share_modes = data->u.s.num_share_mode_entries;
 446         struct share_mode_entry *shares =
 447                 (struct share_mode_entry *)(data + 1);
 448         int i;
 449
 450         for (i = 0; i < num_share_modes; i++) {
 451                 struct share_mode_entry entry;
 452
 453                 memcpy(&entry, &shares[i], sizeof(struct share_mode_entry));
 454                 DEBUG(10,("print_share_mode_table: %s\n",
 455                           share_mode_str(i, &entry)));
 456         }
 457 }
 458
 459 /*******************************************************************
 460  Get all share mode entries for a dev/inode pair.
 461 ********************************************************************/
 462
 463 static BOOL parse_share_modes(TDB_DATA dbuf, struct share_mode_lock *lck)
 464 {
 465         struct locking_data *data;
 466         int i;
 467
 468         if (dbuf.dsize < sizeof(struct locking_data)) {
 469                 smb_panic("PANIC: parse_share_modes: buffer too short.\n");
 470         }
 471
 472         data = (struct locking_data *)dbuf.dptr;
 473
 474         lck->delete_on_close = data->u.s.delete_on_close;
 475         lck->initial_delete_on_close = data->u.s.initial_delete_on_close;
 476         lck->num_share_modes = data->u.s.num_share_mode_entries;
 477
 478         DEBUG(10, ("parse_share_modes: delete_on_close: %d, "
 479                    "initial_delete_on_close: %d, "
 480                    "num_share_modes: %d\n",
 481                 lck->delete_on_close,
 482                 lck->initial_delete_on_close,
 483                 lck->num_share_modes));
 484
 485         if ((lck->num_share_modes < 0) || (lck->num_share_modes > 1000000)) {
 486                 DEBUG(0, ("invalid number of share modes: %d\n",
 487                           lck->num_share_modes));
 488                 smb_panic("PANIC: invalid number of share modes");
 489         }
 490
 491         lck->share_modes = NULL;
 492
 493         if (lck->num_share_modes != 0) {
 494
 495                 if (dbuf.dsize < (sizeof(struct locking_data) +
 496                                   (lck->num_share_modes *
 497                                    sizeof(struct share_mode_entry)))) {
 498                         smb_panic("PANIC: parse_share_modes: buffer too short.\n");
 499                 }
 500
 501                 lck->share_modes = (struct share_mode_entry *)
 502                         talloc_memdup(lck, dbuf.dptr+sizeof(*data),
 503                                       lck->num_share_modes *
 504                                       sizeof(struct share_mode_entry));
 505
 506                 if (lck->share_modes == NULL) {
 507                         smb_panic("talloc failed\n");
 508                 }
 509         }
 510
 511         /* Get any delete token. */
 512         if (data->u.s.delete_token_size) {
 513                 char *p = dbuf.dptr + sizeof(*data) +
 514                                 (lck->num_share_modes *
 515                                 sizeof(struct share_mode_entry));
 516
 517                 if ((data->u.s.delete_token_size < sizeof(uid_t) + sizeof(gid_t)) ||
 518                                 ((data->u.s.delete_token_size - sizeof(uid_t)) % sizeof(gid_t)) != 0) {
 519                         DEBUG(0, ("parse_share_modes: invalid token size %d\n",
 520                                 data->u.s.delete_token_size));
 521                         smb_panic("parse_share_modes: invalid token size\n");
 522                 }
 523
 524                 lck->delete_token = TALLOC_P(lck, UNIX_USER_TOKEN);
 525                 if (!lck->delete_token) {
 526                         smb_panic("talloc failed\n");
 527                 }
 528
 529                 /* Copy out the uid and gid. */
 530                 memcpy(&lck->delete_token->uid, p, sizeof(uid_t));
 531                 p += sizeof(uid_t);
 532                 memcpy(&lck->delete_token->gid, p, sizeof(gid_t));
 533                 p += sizeof(gid_t);
 534
 535                 /* Any supplementary groups ? */
 536                 lck->delete_token->ngroups = (data->u.s.delete_token_size > (sizeof(uid_t) + sizeof(gid_t))) ?
 537                                         ((data->u.s.delete_token_size -
 538                                                 (sizeof(uid_t) + sizeof(gid_t)))/sizeof(gid_t)) : 0;
 539
 540                 if (lck->delete_token->ngroups) {
 541                         /* Make this a talloc child of lck->delete_token. */
 542                         lck->delete_token->groups = TALLOC_ARRAY(lck->delete_token, gid_t,
 543                                                         lck->delete_token->ngroups);
 544                         if (!lck->delete_token) {
 545                                 smb_panic("talloc failed\n");
 546                         }
 547
 548                         for (i = 0; i < lck->delete_token->ngroups; i++) {
 549                                 memcpy(&lck->delete_token->groups[i], p, sizeof(gid_t));
 550                                 p += sizeof(gid_t);
 551                         }
 552                 }
 553
 554         } else {
 555                 lck->delete_token = NULL;
 556         }
 557
 558         /* Save off the associated service path and filename. */
 559         lck->servicepath = talloc_strdup(lck, dbuf.dptr + sizeof(*data) +
 560                                         (lck->num_share_modes *
 561                                         sizeof(struct share_mode_entry)) +
 562                                         data->u.s.delete_token_size );
 563
 564         lck->filename = talloc_strdup(lck, dbuf.dptr + sizeof(*data) +
 565                                         (lck->num_share_modes *
 566                                         sizeof(struct share_mode_entry)) +
 567                                         data->u.s.delete_token_size +
 568                                         strlen(lck->servicepath) + 1 );
 569
 570         /*
 571          * Ensure that each entry has a real process attached.
 572          */
 573
 574         for (i = 0; i < lck->num_share_modes; i++) {
 575                 struct share_mode_entry *entry_p = &lck->share_modes[i];
 576                 DEBUG(10,("parse_share_modes: %s\n",
 577                           share_mode_str(i, entry_p) ));
 578                 if (!process_exists(entry_p->pid)) {
 579                         DEBUG(10,("parse_share_modes: deleted %s\n",
 580                                   share_mode_str(i, entry_p) ));
 581                         entry_p->op_type = UNUSED_SHARE_MODE_ENTRY;
 582                         lck->modified = True;
 583                 }
 584         }
 585
 586         return True;
 587 }
 588
 589 static TDB_DATA unparse_share_modes(struct share_mode_lock *lck)
 590 {
 591         TDB_DATA result;
 592         int num_valid = 0;
 593         int i;
 594         struct locking_data *data;
 595         ssize_t offset;
 596         ssize_t sp_len;
 597         uint32 delete_token_size;
 598
 599         result.dptr = NULL;
 600         result.dsize = 0;
 601
 602         for (i=0; i<lck->num_share_modes; i++) {
 603                 if (!is_unused_share_mode_entry(&lck->share_modes[i])) {
 604                         num_valid += 1;
 605                 }
 606         }
 607
 608         if (num_valid == 0) {
 609                 return result;
 610         }
 611
 612         sp_len = strlen(lck->servicepath);
 613         delete_token_size = (lck->delete_token ?
 614                         (sizeof(uid_t) + sizeof(gid_t) + (lck->delete_token->ngroups*sizeof(gid_t))) : 0);
 615
 616         result.dsize = sizeof(*data) +
 617                 lck->num_share_modes * sizeof(struct share_mode_entry) +
 618                 delete_token_size +
 619                 sp_len + 1 +
 620                 strlen(lck->filename) + 1;
 621         result.dptr = TALLOC_ARRAY(lck, char, result.dsize);
 622
 623         if (result.dptr == NULL) {
 624                 smb_panic("talloc failed\n");
 625         }
 626
 627         data = (struct locking_data *)result.dptr;
 628         ZERO_STRUCTP(data);
 629         data->u.s.num_share_mode_entries = lck->num_share_modes;
 630         data->u.s.delete_on_close = lck->delete_on_close;
 631         data->u.s.initial_delete_on_close = lck->initial_delete_on_close;
 632         data->u.s.delete_token_size = delete_token_size;
 633         DEBUG(10, ("unparse_share_modes: del: %d, initial del %d, tok = %u, num: %d\n",
 634                 data->u.s.delete_on_close,
 635                 data->u.s.initial_delete_on_close,
 636                 (unsigned int)data->u.s.delete_token_size,
 637                 data->u.s.num_share_mode_entries));
 638         memcpy(result.dptr + sizeof(*data), lck->share_modes,
 639                sizeof(struct share_mode_entry)*lck->num_share_modes);
 640         offset = sizeof(*data) +
 641                 sizeof(struct share_mode_entry)*lck->num_share_modes;
 642
 643         /* Store any delete on close token. */
 644         if (lck->delete_token) {
 645                 char *p = result.dptr + offset;
 646
 647                 memcpy(p, &lck->delete_token->uid, sizeof(uid_t));
 648                 p += sizeof(uid_t);
 649
 650                 memcpy(p, &lck->delete_token->gid, sizeof(gid_t));
 651                 p += sizeof(gid_t);
 652
 653                 for (i = 0; i < lck->delete_token->ngroups; i++) {
 654                         memcpy(p, &lck->delete_token->groups[i], sizeof(gid_t));
 655                         p += sizeof(gid_t);
 656                 }
 657                 offset = p - result.dptr;
 658         }
 659
 660         safe_strcpy(result.dptr + offset, lck->servicepath,
 661                     result.dsize - offset - 1);
 662         offset += sp_len + 1;
 663         safe_strcpy(result.dptr + offset, lck->filename,
 664                     result.dsize - offset - 1);
 665
 666         if (DEBUGLEVEL >= 10) {
 667                 print_share_mode_table(data);
 668         }
 669
 670         return result;
 671 }
 672
 673 static int share_mode_lock_destructor(void *p)
 674 {
 675         struct share_mode_lock *lck =
 676                 talloc_get_type_abort(p, struct share_mode_lock);
 677         TDB_DATA key = locking_key(lck->dev, lck->ino);
 678         TDB_DATA data;
 679
 680         if (!lck->modified) {
 681                 goto done;
 682         }
 683
 684         data = unparse_share_modes(lck);
 685
 686         if (data.dptr == NULL) {
 687                 if (!lck->fresh) {
 688                         /* There has been an entry before, delete it */
 689                         if (tdb_delete(tdb, key) == -1) {
 690                                 smb_panic("Could not delete share entry\n");
 691                         }
 692                 }
 693                 goto done;
 694         }
 695
 696         if (tdb_store(tdb, key, data, TDB_REPLACE) == -1) {
 697                 smb_panic("Could not store share mode entry\n");
 698         }
 699
 700  done:
 701         tdb_chainunlock(tdb, key);
 702
 703         return 0;
 704 }
 705
 706 struct share_mode_lock *get_share_mode_lock(TALLOC_CTX *mem_ctx,
 707                                                 SMB_DEV_T dev, SMB_INO_T ino,
 708                                                 const char *servicepath,
 709                                                 const char *fname)
 710 {
 711         struct share_mode_lock *lck;
 712         TDB_DATA key = locking_key(dev, ino);
 713         TDB_DATA data;
 714
 715         lck = TALLOC_P(mem_ctx, struct share_mode_lock);
 716         if (lck == NULL) {
 717                 DEBUG(0, ("talloc failed\n"));
 718                 return NULL;
 719         }
 720
 721         /* Ensure we set every field here as the destructor must be
 722            valid even if parse_share_modes fails. */
 723
 724         lck->servicepath = NULL;
 725         lck->filename = NULL;
 726         lck->dev = dev;
 727         lck->ino = ino;
 728         lck->num_share_modes = 0;
 729         lck->share_modes = NULL;
 730         lck->delete_token = NULL;
 731         lck->delete_on_close = False;
 732         lck->initial_delete_on_close = False;
 733         lck->fresh = False;
 734         lck->modified = False;
 735
 736         if (tdb_chainlock(tdb, key) != 0) {
 737                 DEBUG(3, ("Could not lock share entry\n"));
 738                 TALLOC_FREE(lck);
 739                 return NULL;
 740         }
 741
 742         /* We must set the destructor immediately after the chainlock
 743            ensure the lock is cleaned up on any of the error return
 744            paths below. */
 745
 746         talloc_set_destructor(lck, share_mode_lock_destructor);
 747
 748         data = tdb_fetch(tdb, key);
 749         lck->fresh = (data.dptr == NULL);
 750
 751         if (lck->fresh) {
 752
 753                 if (fname == NULL || servicepath == NULL) {
 754                         TALLOC_FREE(lck);
 755                         return NULL;
 756                 }
 757                 lck->filename = talloc_strdup(lck, fname);
 758                 lck->servicepath = talloc_strdup(lck, servicepath);
 759                 if (lck->filename == NULL || lck->servicepath == NULL) {
 760                         DEBUG(0, ("talloc failed\n"));
 761                         TALLOC_FREE(lck);
 762                         return NULL;
 763                 }
 764         } else {
 765                 if (!parse_share_modes(data, lck)) {
 766                         DEBUG(0, ("Could not parse share modes\n"));
 767                         TALLOC_FREE(lck);
 768                         SAFE_FREE(data.dptr);
 769                         return NULL;
 770                 }
 771         }
 772
 773         SAFE_FREE(data.dptr);
 774
 775         return lck;
 776 }
 777
 778 /*******************************************************************
 779  Sets the service name and filename for rename.
 780  At this point we emit "file renamed" messages to all
 781  process id's that have this file open.
 782  Based on an initial code idea from SATOH Fumiyasu <fumiya@samba.gr.jp>
 783 ********************************************************************/
 784
 785 BOOL rename_share_filename(struct share_mode_lock *lck,
 786                         const char *servicepath,
 787                         const char *newname)
 788 {
 789         size_t sp_len;
 790         size_t fn_len;
 791         size_t msg_len;
 792         char *frm = NULL;
 793         int i;
 794
 795         if (!lck) {
 796                 return False;
 797         }
 798
 799         DEBUG(10, ("rename_share_filename: servicepath %s newname %s\n",
 800                 servicepath, newname));
 801
 802         /*
 803          * rename_internal_fsp() and rename_internals() add './' to
 804          * head of newname if newname does not contain a '/'.
 805          */
 806         while (newname[0] && newname[1] && newname[0] == '.' && newname[1] == '/') {
 807                 newname += 2;
 808         }
 809
 810         lck->servicepath = talloc_strdup(lck, servicepath);
 811         lck->filename = talloc_strdup(lck, newname);
 812         if (lck->filename == NULL || lck->servicepath == NULL) {
 813                 DEBUG(0, ("rename_share_filename: talloc failed\n"));
 814                 return False;
 815         }
 816         lck->modified = True;
 817
 818         sp_len = strlen(lck->servicepath);
 819         fn_len = strlen(lck->filename);
 820
 821         msg_len = MSG_FILE_RENAMED_MIN_SIZE + sp_len + 1 + fn_len + 1;
 822
 823         /* Set up the name changed message. */
 824         frm = TALLOC_ARRAY(lck, char, msg_len);
 825         if (!frm) {
 826                 return False;
 827         }
 828
 829         SDEV_T_VAL(frm,0,lck->dev);
 830         SINO_T_VAL(frm,8,lck->ino);
 831
 832         DEBUG(10,("rename_share_filename: msg_len = %u\n", (unsigned int)msg_len ));
 833
 834         safe_strcpy(&frm[16], lck->servicepath, sp_len);
 835         safe_strcpy(&frm[16 + sp_len + 1], lck->filename, fn_len);
 836
 837         /* Send the messages. */
 838         for (i=0; i<lck->num_share_modes; i++) {
 839                 struct share_mode_entry *se = &lck->share_modes[i];
 840                 if (!is_valid_share_mode_entry(se)) {
 841                         continue;
 842                 }
 843                 /* But not to ourselves... */
 844                 if (procid_is_me(&se->pid)) {
 845                         continue;
 846                 }
 847
 848                 DEBUG(10,("rename_share_filename: sending rename message to pid %s "
 849                         "dev %x, inode  %.0f sharepath %s newname %s\n",
 850                         procid_str_static(&se->pid),
 851                         (unsigned int)lck->dev, (double)lck->ino,
 852                         lck->servicepath, lck->filename ));
 853
 854                 message_send_pid(se->pid, MSG_SMB_FILE_RENAME,
 855                                 frm, msg_len, True);
 856         }
 857
 858         return True;
 859 }
 860
 861 BOOL get_delete_on_close_flag(SMB_DEV_T dev, SMB_INO_T inode)
 862 {
 863         BOOL result;
 864         struct share_mode_lock *lck = get_share_mode_lock(NULL, dev, inode, NULL, NULL);
 865         if (!lck) {
 866                 return False;
 867         }
 868         result = lck->delete_on_close;
 869         TALLOC_FREE(lck);
 870         return result;
 871 }
 872
 873 BOOL is_valid_share_mode_entry(const struct share_mode_entry *e)
 874 {
 875         int num_props = 0;
 876
 877         num_props += ((e->op_type == NO_OPLOCK) ? 1 : 0);
 878         num_props += (EXCLUSIVE_OPLOCK_TYPE(e->op_type) ? 1 : 0);
 879         num_props += (LEVEL_II_OPLOCK_TYPE(e->op_type) ? 1 : 0);
 880
 881         SMB_ASSERT(num_props <= 1);
 882         return (num_props != 0);
 883 }
 884
 885 BOOL is_deferred_open_entry(const struct share_mode_entry *e)
 886 {
 887         return (e->op_type == DEFERRED_OPEN_ENTRY);
 888 }
 889
 890 BOOL is_unused_share_mode_entry(const struct share_mode_entry *e)
 891 {
 892         return (e->op_type == UNUSED_SHARE_MODE_ENTRY);
 893 }
 894
 895 /*******************************************************************
 896  Fill a share mode entry.
 897 ********************************************************************/
 898
 899 static void fill_share_mode_entry(struct share_mode_entry *e,
 900                                   files_struct *fsp,
 901                                   uid_t uid, uint16 mid, uint16 op_type)
 902 {
 903         ZERO_STRUCTP(e);
 904         e->pid = procid_self();
 905         e->share_access = fsp->share_access;
 906         e->private_options = fsp->fh->private_options;
 907         e->access_mask = fsp->access_mask;
 908         e->op_mid = mid;
 909         e->op_type = op_type;
 910         e->time.tv_sec = fsp->open_time.tv_sec;
 911         e->time.tv_usec = fsp->open_time.tv_usec;
 912         e->dev = fsp->dev;
 913         e->inode = fsp->inode;
 914         e->share_file_id = fsp->fh->file_id;
 915         e->uid = (uint32)uid;
 916 }
 917
 918 static void fill_deferred_open_entry(struct share_mode_entry *e,
 919                                      const struct timeval request_time,
 920                                      SMB_DEV_T dev, SMB_INO_T ino, uint16 mid)
 921 {
 922         ZERO_STRUCTP(e);
 923         e->pid = procid_self();
 924         e->op_mid = mid;
 925         e->op_type = DEFERRED_OPEN_ENTRY;
 926         e->time.tv_sec = request_time.tv_sec;
 927         e->time.tv_usec = request_time.tv_usec;
 928         e->dev = dev;
 929         e->inode = ino;
 930         e->uid = (uint32)-1;
 931 }
 932
 933 static void add_share_mode_entry(struct share_mode_lock *lck,
 934                                  const struct share_mode_entry *entry)
 935 {
 936         int i;
 937
 938         for (i=0; i<lck->num_share_modes; i++) {
 939                 struct share_mode_entry *e = &lck->share_modes[i];
 940                 if (is_unused_share_mode_entry(e)) {
 941                         *e = *entry;
 942                         break;
 943                 }
 944         }
 945
 946         if (i == lck->num_share_modes) {
 947                 /* No unused entry found */
 948                 ADD_TO_ARRAY(lck, struct share_mode_entry, *entry,
 949                              &lck->share_modes, &lck->num_share_modes);
 950         }
 951         lck->modified = True;
 952 }
 953
 954 void set_share_mode(struct share_mode_lock *lck, files_struct *fsp,
 955                         uid_t uid, uint16 mid, uint16 op_type)
 956 {
 957         struct share_mode_entry entry;
 958         fill_share_mode_entry(&entry, fsp, uid, mid, op_type);
 959         add_share_mode_entry(lck, &entry);
 960 }
 961
 962 void add_deferred_open(struct share_mode_lock *lck, uint16 mid,
 963                        struct timeval request_time,
 964                        SMB_DEV_T dev, SMB_INO_T ino)
 965 {
 966         struct share_mode_entry entry;
 967         fill_deferred_open_entry(&entry, request_time, dev, ino, mid);
 968         add_share_mode_entry(lck, &entry);
 969 }
 970
 971 /*******************************************************************
 972  Check if two share mode entries are identical, ignoring oplock
 973  and mid info and desired_access. (Removed paranoia test - it's
 974  not automatically a logic error if they are identical. JRA.)
 975 ********************************************************************/
 976
 977 static BOOL share_modes_identical(struct share_mode_entry *e1,
 978                                   struct share_mode_entry *e2)
 979 {
 980         /* We used to check for e1->share_access == e2->share_access here
 981            as well as the other fields but 2 different DOS or FCB opens
 982            sharing the same share mode entry may validly differ in
 983            fsp->share_access field. */
 984
 985         return (procid_equal(&e1->pid, &e2->pid) &&
 986                 e1->dev == e2->dev &&
 987                 e1->inode == e2->inode &&
 988                 e1->share_file_id == e2->share_file_id );
 989 }
 990
 991 static BOOL deferred_open_identical(struct share_mode_entry *e1,
 992                                     struct share_mode_entry *e2)
 993 {
 994         return (procid_equal(&e1->pid, &e2->pid) &&
 995                 (e1->op_mid == e2->op_mid) &&
 996                 (e1->dev == e2->dev) &&
 997                 (e1->inode == e2->inode));
 998 }
 999
1000 static struct share_mode_entry *find_share_mode_entry(struct share_mode_lock *lck,
1001                                                       struct share_mode_entry *entry)
1002 {
1003         int i;
1004
1005         for (i=0; i<lck->num_share_modes; i++) {
1006                 struct share_mode_entry *e = &lck->share_modes[i];
1007                 if (is_valid_share_mode_entry(entry) &&
1008                     is_valid_share_mode_entry(e) &&
1009                     share_modes_identical(e, entry)) {
1010                         return e;
1011                 }
1012                 if (is_deferred_open_entry(entry) &&
1013                     is_deferred_open_entry(e) &&
1014                     deferred_open_identical(e, entry)) {
1015                         return e;
1016                 }
1017         }
1018         return NULL;
1019 }
1020
1021 /*******************************************************************
1022  Del the share mode of a file for this process. Return the number of
1023  entries left.
1024 ********************************************************************/
1025
1026 BOOL del_share_mode(struct share_mode_lock *lck, files_struct *fsp)
1027 {
1028         struct share_mode_entry entry, *e;
1029
1030         /* Don't care about the pid owner being correct here - just a search. */
1031         fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);
1032
1033         e = find_share_mode_entry(lck, &entry);
1034         if (e == NULL) {
1035                 return False;
1036         }
1037
1038         e->op_type = UNUSED_SHARE_MODE_ENTRY;
1039         lck->modified = True;
1040         return True;
1041 }
1042
1043 void del_deferred_open_entry(struct share_mode_lock *lck, uint16 mid)
1044 {
1045         struct share_mode_entry entry, *e;
1046
1047         fill_deferred_open_entry(&entry, timeval_zero(),
1048                                  lck->dev, lck->ino, mid);
1049
1050         e = find_share_mode_entry(lck, &entry);
1051         if (e == NULL) {
1052                 return;
1053         }
1054
1055         e->op_type = UNUSED_SHARE_MODE_ENTRY;
1056         lck->modified = True;
1057 }
1058
1059 /*******************************************************************
1060  Remove an oplock mid and mode entry from a share mode.
1061 ********************************************************************/
1062
1063 BOOL remove_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
1064 {
1065         struct share_mode_entry entry, *e;
1066
1067         /* Don't care about the pid owner being correct here - just a search. */
1068         fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);
1069
1070         e = find_share_mode_entry(lck, &entry);
1071         if (e == NULL) {
1072                 return False;
1073         }
1074
1075         e->op_mid = 0;
1076         e->op_type = NO_OPLOCK;
1077         lck->modified = True;
1078         return True;
1079 }
1080
1081 /*******************************************************************
1082  Downgrade a oplock type from exclusive to level II.
1083 ********************************************************************/
1084
1085 BOOL downgrade_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
1086 {
1087         struct share_mode_entry entry, *e;
1088
1089         /* Don't care about the pid owner being correct here - just a search. */
1090         fill_share_mode_entry(&entry, fsp, (uid_t)-1, 0, NO_OPLOCK);
1091
1092         e = find_share_mode_entry(lck, &entry);
1093         if (e == NULL) {
1094                 return False;
1095         }
1096
1097         e->op_type = LEVEL_II_OPLOCK;
1098         lck->modified = True;
1099         return True;
1100 }
1101
1102 /****************************************************************************
1103  Deal with the internal needs of setting the delete on close flag. Note that
1104  as the tdb locking is recursive, it is safe to call this from within
1105  open_file_ntcreate. JRA.
1106 ****************************************************************************/
1107
1108 NTSTATUS can_set_delete_on_close(files_struct *fsp, BOOL delete_on_close,
1109                                  uint32 dosmode)
1110 {
1111         if (!delete_on_close) {
1112                 return NT_STATUS_OK;
1113         }
1114
1115         /*
1116          * Only allow delete on close for writable files.
1117          */
1118
1119         if ((dosmode & aRONLY) &&
1120             !lp_delete_readonly(SNUM(fsp->conn))) {
1121                 DEBUG(10,("can_set_delete_on_close: file %s delete on close "
1122                           "flag set but file attribute is readonly.\n",
1123                           fsp->fsp_name ));
1124                 return NT_STATUS_CANNOT_DELETE;
1125         }
1126
1127         /*
1128          * Only allow delete on close for writable shares.
1129          */
1130
1131         if (!CAN_WRITE(fsp->conn)) {
1132                 DEBUG(10,("can_set_delete_on_close: file %s delete on "
1133                           "close flag set but write access denied on share.\n",
1134                           fsp->fsp_name ));
1135                 return NT_STATUS_ACCESS_DENIED;
1136         }
1137
1138         /*
1139          * Only allow delete on close for files/directories opened with delete
1140          * intent.
1141          */
1142
1143         if (!(fsp->access_mask & DELETE_ACCESS)) {
1144                 DEBUG(10,("can_set_delete_on_close: file %s delete on "
1145                           "close flag set but delete access denied.\n",
1146                           fsp->fsp_name ));
1147                 return NT_STATUS_ACCESS_DENIED;
1148         }
1149
1150         return NT_STATUS_OK;
1151 }
1152
1153 /*************************************************************************
1154  Return a talloced copy of a UNIX_USER_TOKEN. NULL on fail.
1155  (Should this be in locking.c.... ?).
1156 *************************************************************************/
1157
1158 static UNIX_USER_TOKEN *copy_unix_token(TALLOC_CTX *ctx, UNIX_USER_TOKEN *tok)
1159 {
1160         UNIX_USER_TOKEN *cpy;
1161
1162         if (tok == NULL) {
1163                 return NULL;
1164         }
1165
1166         cpy = TALLOC_P(ctx, UNIX_USER_TOKEN);
1167         if (!cpy) {
1168                 return NULL;
1169         }
1170
1171         cpy->uid = tok->uid;
1172         cpy->gid = tok->gid;
1173         cpy->ngroups = tok->ngroups;
1174         if (tok->ngroups) {
1175                 /* Make this a talloc child of cpy. */
1176                 cpy->groups = TALLOC_ARRAY(cpy, gid_t, tok->ngroups);
1177                 if (!cpy->groups) {
1178                         return NULL;
1179                 }
1180                 memcpy(cpy->groups, tok->groups, tok->ngroups * sizeof(gid_t));
1181         }
1182         return cpy;
1183 }
1184
1185 /****************************************************************************
1186  Replace the delete on close token.
1187 ****************************************************************************/
1188
1189 void set_delete_on_close_token(struct share_mode_lock *lck, UNIX_USER_TOKEN *tok)
1190 {
1191         /* Ensure there's no token. */
1192         if (lck->delete_token) {
1193                 TALLOC_FREE(lck->delete_token); /* Also deletes groups... */
1194                 lck->delete_token = NULL;
1195         }
1196
1197         /* Copy the new token (can be NULL). */
1198         lck->delete_token = copy_unix_token(lck, tok);
1199         lck->modified = True;
1200 }
1201
1202 /****************************************************************************
1203  Sets the delete on close flag over all share modes on this file.
1204  Modify the share mode entry for all files open
1205  on this device and inode to tell other smbds we have
1206  changed the delete on close flag. This will be noticed
1207  in the close code, the last closer will delete the file
1208  if flag is set.
1209  Note that setting this to any value clears the initial_delete_on_close flag.
1210  If delete_on_close is True this makes a copy of any UNIX_USER_TOKEN into the
1211  lck entry.
1212 ****************************************************************************/
1213
1214 BOOL set_delete_on_close(files_struct *fsp, BOOL delete_on_close, UNIX_USER_TOKEN *tok)
1215 {
1216         struct share_mode_lock *lck;
1217
1218         DEBUG(10,("set_delete_on_close: %s delete on close flag for "
1219                   "fnum = %d, file %s\n",
1220                   delete_on_close ? "Adding" : "Removing", fsp->fnum,
1221                   fsp->fsp_name ));
1222
1223         if (fsp->is_stat) {
1224                 return True;
1225         }
1226
1227         lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
1228         if (lck == NULL) {
1229                 return False;
1230         }
1231
1232         if (lck->delete_on_close != delete_on_close) {
1233                 set_delete_on_close_token(lck, tok);
1234                 lck->delete_on_close = delete_on_close;
1235                 if (delete_on_close) {
1236                         SMB_ASSERT(lck->delete_token != NULL);
1237                 }
1238                 lck->modified = True;
1239         }
1240
1241         if (lck->initial_delete_on_close) {
1242                 lck->initial_delete_on_close = False;
1243                 lck->modified = True;
1244         }
1245
1246         TALLOC_FREE(lck);
1247         return True;
1248 }
1249
1250 struct forall_state {
1251         void (*fn)(const struct share_mode_entry *entry,
1252                    const char *sharepath,
1253                    const char *fname,
1254                    void *private_data);
1255         void *private_data;
1256 };
1257
1258 static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf,
1259                        void *_state)
1260 {
1261         struct forall_state *state = (struct forall_state *)_state;
1262         struct locking_data *data;
1263         struct share_mode_entry *shares;
1264         const char *sharepath;
1265         const char *fname;
1266         int i;
1267
1268         /* Ensure this is a locking_key record. */
1269         if (kbuf.dsize != sizeof(struct locking_key))
1270                 return 0;
1271
1272         data = (struct locking_data *)dbuf.dptr;
1273         shares = (struct share_mode_entry *)(dbuf.dptr + sizeof(*data));
1274         sharepath = dbuf.dptr + sizeof(*data) +
1275                 data->u.s.num_share_mode_entries*sizeof(*shares) +
1276                 data->u.s.delete_token_size;
1277         fname = dbuf.dptr + sizeof(*data) +
1278                 data->u.s.num_share_mode_entries*sizeof(*shares) +
1279                 data->u.s.delete_token_size +
1280                 strlen(sharepath) + 1;
1281
1282         for (i=0;i<data->u.s.num_share_mode_entries;i++) {
1283                 state->fn(&shares[i], sharepath, fname,
1284                           state->private_data);
1285         }
1286         return 0;
1287 }
1288
1289 /*******************************************************************
1290  Call the specified function on each entry under management by the
1291  share mode system.
1292 ********************************************************************/
1293
1294 int share_mode_forall(void (*fn)(const struct share_mode_entry *, const char *,
1295                                  const char *, void *),
1296                       void *private_data)
1297 {
1298         struct forall_state state;
1299
1300         if (tdb == NULL)
1301                 return 0;
1302
1303         state.fn = fn;
1304         state.private_data = private_data;
1305
1306         return tdb_traverse(tdb, traverse_fn, (void *)&state);
1307 }