source3/smbd/oplock.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    oplock processing
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 1998 - 2001
   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 3 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, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #define DBGC_CLASS DBGC_LOCKING
  23 #include "includes.h"
  24 #include "lib/util/server_id.h"
  25 #include "smbd/smbd.h"
  26 #include "smbd/globals.h"
  27 #include "messages.h"
  28 #include "locking/leases_db.h"
  29 #include "../librpc/gen_ndr/ndr_open_files.h"
  30
  31 /*
  32  * helper function used by the kernel oplock backends to post the break message
  33  */
  34 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  35 {
  36         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  37
  38         /* Put the kernel break info into the message. */
  39         push_file_id_24((char *)msg, &fsp->file_id);
  40         SIVAL(msg,24,fsp->fh->gen_id);
  41
  42         /* Don't need to be root here as we're only ever
  43            sending to ourselves. */
  44
  45         messaging_send_buf(msg_ctx, messaging_server_id(msg_ctx),
  46                            MSG_SMB_KERNEL_BREAK,
  47                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  48 }
  49
  50 /****************************************************************************
  51  Attempt to set an oplock on a file. Succeeds if kernel oplocks are
  52  disabled (just sets flags).
  53 ****************************************************************************/
  54
  55 NTSTATUS set_file_oplock(files_struct *fsp)
  56 {
  57         struct smbd_server_connection *sconn = fsp->conn->sconn;
  58         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
  59         bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
  60                         (koplocks != NULL);
  61
  62         if (fsp->oplock_type == LEVEL_II_OPLOCK && use_kernel) {
  63                 DEBUG(10, ("Refusing level2 oplock, kernel oplocks "
  64                            "don't support them\n"));
  65                 return NT_STATUS_NOT_SUPPORTED;
  66         }
  67
  68         if ((fsp->oplock_type != NO_OPLOCK) &&
  69             use_kernel &&
  70             !koplocks->ops->set_oplock(koplocks, fsp, fsp->oplock_type))
  71         {
  72                 return map_nt_error_from_unix(errno);
  73         }
  74
  75         fsp->sent_oplock_break = NO_BREAK_SENT;
  76         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  77                 sconn->oplocks.level_II_open++;
  78         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  79                 sconn->oplocks.exclusive_open++;
  80         }
  81
  82         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  83                     "tv_sec = %x, tv_usec = %x\n",
  84                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  85                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  86                  (int)fsp->open_time.tv_usec ));
  87
  88         return NT_STATUS_OK;
  89 }
  90
  91 static void release_fsp_kernel_oplock(files_struct *fsp)
  92 {
  93         struct smbd_server_connection *sconn = fsp->conn->sconn;
  94         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
  95         bool use_kernel;
  96
  97         if (koplocks == NULL) {
  98                 return;
  99         }
 100         use_kernel = lp_kernel_oplocks(SNUM(fsp->conn));
 101         if (!use_kernel) {
 102                 return;
 103         }
 104         if (fsp->oplock_type == NO_OPLOCK) {
 105                 return;
 106         }
 107         if (fsp->oplock_type == LEASE_OPLOCK) {
 108                 /*
 109                  * For leases we don't touch kernel oplocks at all
 110                  */
 111                 return;
 112         }
 113
 114         koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 115 }
 116
 117 /****************************************************************************
 118  Attempt to release an oplock on a file. Decrements oplock count.
 119 ****************************************************************************/
 120
 121 static void release_file_oplock(files_struct *fsp)
 122 {
 123         struct smbd_server_connection *sconn = fsp->conn->sconn;
 124
 125         release_fsp_kernel_oplock(fsp);
 126
 127         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 128                 sconn->oplocks.level_II_open--;
 129         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 130                 sconn->oplocks.exclusive_open--;
 131         }
 132
 133         SMB_ASSERT(sconn->oplocks.exclusive_open>=0);
 134         SMB_ASSERT(sconn->oplocks.level_II_open>=0);
 135
 136         fsp->oplock_type = NO_OPLOCK;
 137         fsp->sent_oplock_break = NO_BREAK_SENT;
 138
 139         flush_write_cache(fsp, SAMBA_OPLOCK_RELEASE_FLUSH);
 140         delete_write_cache(fsp);
 141
 142         TALLOC_FREE(fsp->oplock_timeout);
 143 }
 144
 145 /****************************************************************************
 146  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 147 ****************************************************************************/
 148
 149 static void downgrade_file_oplock(files_struct *fsp)
 150 {
 151         struct smbd_server_connection *sconn = fsp->conn->sconn;
 152         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 153         bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
 154                         (koplocks != NULL);
 155
 156         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 157                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 158                 return;
 159         }
 160
 161         if (use_kernel) {
 162                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 163         }
 164         fsp->oplock_type = LEVEL_II_OPLOCK;
 165         sconn->oplocks.exclusive_open--;
 166         sconn->oplocks.level_II_open++;
 167         fsp->sent_oplock_break = NO_BREAK_SENT;
 168
 169         flush_write_cache(fsp, SAMBA_OPLOCK_RELEASE_FLUSH);
 170         delete_write_cache(fsp);
 171
 172         TALLOC_FREE(fsp->oplock_timeout);
 173 }
 174
 175 uint32_t get_lease_type(const struct share_mode_data *d,
 176                         const struct share_mode_entry *e)
 177 {
 178         if (e->op_type == LEASE_OPLOCK) {
 179                 NTSTATUS status;
 180                 uint32_t current_state;
 181
 182                 status = leases_db_get(
 183                         &e->client_guid,
 184                         &e->lease_key,
 185                         &d->id,
 186                         &current_state,
 187                         NULL,   /* breaking */
 188                         NULL,   /* breaking_to_requested */
 189                         NULL,   /* breaking_to_required */
 190                         NULL,   /* lease_version */
 191                         NULL);  /* epoch */
 192                 SMB_ASSERT(NT_STATUS_IS_OK(status));
 193                 return current_state;
 194         }
 195         return map_oplock_to_lease_type(e->op_type);
 196 }
 197
 198 bool update_num_read_oplocks(files_struct *fsp, struct share_mode_lock *lck)
 199 {
 200         struct share_mode_data *d = lck->data;
 201         struct byte_range_lock *br_lck;
 202         uint32_t num_read_oplocks = 0;
 203         uint32_t i;
 204
 205         if (fsp_lease_type_is_exclusive(fsp)) {
 206                 const struct share_mode_entry *e = NULL;
 207                 uint32_t e_lease_type = 0;
 208
 209                 /*
 210                  * If we're fully exclusive, we don't need a brlock entry
 211                  */
 212                 remove_stale_share_mode_entries(d);
 213
 214                 e = find_share_mode_entry(lck, fsp);
 215                 if (e != NULL) {
 216                         e_lease_type = get_lease_type(d, e);
 217                 }
 218
 219                 if (!lease_type_is_exclusive(e_lease_type)) {
 220                         char *timestr = NULL;
 221
 222                         timestr = timeval_string(talloc_tos(),
 223                                                  &fsp->open_time,
 224                                                  true);
 225
 226                         NDR_PRINT_DEBUG(share_mode_data, d);
 227                         DBG_ERR("file [%s] file_id [%s] gen_id [%lu] "
 228                                 "open_time[%s] lease_type [0x%x] "
 229                                 "oplock_type [0x%x]\n",
 230                                 fsp_str_dbg(fsp),
 231                                 file_id_string_tos(&fsp->file_id),
 232                                 fsp->fh->gen_id, timestr,
 233                                 e_lease_type, fsp->oplock_type);
 234
 235                         smb_panic("Found non-exclusive lease");
 236                 }
 237
 238                 return true;
 239         }
 240
 241         for (i=0; i<d->num_share_modes; i++) {
 242                 struct share_mode_entry *e = &d->share_modes[i];
 243                 uint32_t e_lease_type = get_lease_type(d, e);
 244
 245                 if (e_lease_type & SMB2_LEASE_READ) {
 246                         num_read_oplocks += 1;
 247                 }
 248         }
 249
 250         br_lck = brl_get_locks_readonly(fsp);
 251         if (br_lck == NULL) {
 252                 return false;
 253         }
 254         if (brl_num_read_oplocks(br_lck) == num_read_oplocks) {
 255                 return true;
 256         }
 257
 258         br_lck = brl_get_locks(talloc_tos(), fsp);
 259         if (br_lck == NULL) {
 260                 return false;
 261         }
 262         brl_set_num_read_oplocks(br_lck, num_read_oplocks);
 263         TALLOC_FREE(br_lck);
 264         return true;
 265 }
 266
 267 /****************************************************************************
 268  Remove a file oplock with lock already held. Copes with level II and exclusive.
 269 ****************************************************************************/
 270
 271 bool remove_oplock_under_lock(files_struct *fsp, struct share_mode_lock *lck)
 272 {
 273         bool ret;
 274
 275         ret = remove_share_oplock(lck, fsp);
 276         if (!ret) {
 277                 DBG_ERR("failed to remove share oplock for "
 278                         "file %s, %s, %s\n",
 279                         fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 280                         file_id_string_tos(&fsp->file_id));
 281         }
 282         release_file_oplock(fsp);
 283
 284         ret = update_num_read_oplocks(fsp, lck);
 285         if (!ret) {
 286                 DBG_ERR("update_num_read_oplocks failed for "
 287                         "file %s, %s, %s\n",
 288                         fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 289                         file_id_string_tos(&fsp->file_id));
 290         }
 291
 292         return ret;
 293 }
 294
 295 /****************************************************************************
 296  Remove a file oplock. Copes with level II and exclusive.
 297  Locks then unlocks the share mode lock. Client can decide to go directly
 298  to none even if a "break-to-level II" was sent.
 299 ****************************************************************************/
 300
 301 bool remove_oplock(files_struct *fsp)
 302 {
 303         bool ret;
 304         struct share_mode_lock *lck;
 305
 306         DBG_DEBUG("remove_oplock called for %s\n", fsp_str_dbg(fsp));
 307
 308         /* Remove the oplock flag from the sharemode. */
 309         lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 310         if (lck == NULL) {
 311                 DBG_ERR("failed to lock share entry for "
 312                          "file %s\n", fsp_str_dbg(fsp));
 313                 return false;
 314         }
 315
 316         ret = remove_oplock_under_lock(fsp, lck);
 317
 318         TALLOC_FREE(lck);
 319         return ret;
 320 }
 321
 322 /*
 323  * Deal with a reply when a break-to-level II was sent.
 324  */
 325 bool downgrade_oplock(files_struct *fsp)
 326 {
 327         bool ret;
 328         struct share_mode_lock *lck;
 329
 330         DEBUG(10, ("downgrade_oplock called for %s\n",
 331                    fsp_str_dbg(fsp)));
 332
 333         lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 334         if (lck == NULL) {
 335                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 336                          "file %s\n", fsp_str_dbg(fsp)));
 337                 return False;
 338         }
 339         ret = downgrade_share_oplock(lck, fsp);
 340         if (!ret) {
 341                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 342                          "for file %s, %s, file_id %s\n",
 343                          fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 344                          file_id_string_tos(&fsp->file_id)));
 345         }
 346         downgrade_file_oplock(fsp);
 347
 348         ret = update_num_read_oplocks(fsp, lck);
 349         if (!ret) {
 350                 DEBUG(0, ("%s: update_num_read_oplocks failed for "
 351                          "file %s, %s, %s\n",
 352                           __func__, fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 353                          file_id_string_tos(&fsp->file_id)));
 354         }
 355
 356         TALLOC_FREE(lck);
 357         return ret;
 358 }
 359
 360 static void lease_timeout_handler(struct tevent_context *ctx,
 361                                   struct tevent_timer *te,
 362                                   struct timeval now,
 363                                   void *private_data)
 364 {
 365         struct fsp_lease *lease =
 366                 talloc_get_type_abort(private_data,
 367                 struct fsp_lease);
 368         struct files_struct *fsp;
 369         struct share_mode_lock *lck;
 370         uint16_t old_epoch = lease->lease.lease_epoch;
 371
 372         fsp = file_find_one_fsp_from_lease_key(lease->sconn,
 373                                                &lease->lease.lease_key);
 374         if (fsp == NULL) {
 375                 /* race? */
 376                 TALLOC_FREE(lease->timeout);
 377                 return;
 378         }
 379
 380         /*
 381          * Paranoia check: There can only be one fsp_lease per lease
 382          * key
 383          */
 384         SMB_ASSERT(fsp->lease == lease);
 385
 386         lck = get_existing_share_mode_lock(
 387                         talloc_tos(), fsp->file_id);
 388         if (lck == NULL) {
 389                 /* race? */
 390                 TALLOC_FREE(lease->timeout);
 391                 return;
 392         }
 393
 394         fsp_lease_update(lck, fsp_client_guid(fsp), lease);
 395
 396         if (lease->lease.lease_epoch != old_epoch) {
 397                 /*
 398                  * If the epoch changed we need to wait for
 399                  * the next timeout to happen.
 400                  */
 401                 DEBUG(10, ("lease break timeout race (epoch) for file %s - ignoring\n",
 402                            fsp_str_dbg(fsp)));
 403                 TALLOC_FREE(lck);
 404                 return;
 405         }
 406
 407         if (!(lease->lease.lease_flags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS)) {
 408                 /*
 409                  * If the epoch changed we need to wait for
 410                  * the next timeout to happen.
 411                  */
 412                 DEBUG(10, ("lease break timeout race (flags) for file %s - ignoring\n",
 413                            fsp_str_dbg(fsp)));
 414                 TALLOC_FREE(lck);
 415                 return;
 416         }
 417
 418         DEBUG(1, ("lease break timed out for file %s -- replying anyway\n",
 419                   fsp_str_dbg(fsp)));
 420         (void)downgrade_lease(lease->sconn->client->connections,
 421                         1,
 422                         &fsp->file_id,
 423                         &lease->lease.lease_key,
 424                         SMB2_LEASE_NONE);
 425
 426         TALLOC_FREE(lck);
 427 }
 428
 429 bool fsp_lease_update(struct share_mode_lock *lck,
 430                       const struct GUID *client_guid,
 431                       struct fsp_lease *lease)
 432 {
 433         uint32_t current_state;
 434         bool breaking;
 435         uint16_t lease_version, epoch;
 436         NTSTATUS status;
 437
 438         status = leases_db_get(client_guid,
 439                                &lease->lease.lease_key,
 440                                &lck->data->id,
 441                                &current_state,
 442                                &breaking,
 443                                NULL, /* breaking_to_requested */
 444                                NULL, /* breaking_to_required */
 445                                &lease_version,
 446                                &epoch);
 447         if (!NT_STATUS_IS_OK(status)) {
 448                 DBG_WARNING("Could not find lease entry: %s\n",
 449                             nt_errstr(status));
 450                 TALLOC_FREE(lease->timeout);
 451                 lease->lease.lease_state = SMB2_LEASE_NONE;
 452                 lease->lease.lease_epoch += 1;
 453                 lease->lease.lease_flags = 0;
 454                 return false;
 455         }
 456
 457         DEBUG(10,("%s: refresh lease state\n", __func__));
 458
 459         /* Ensure we're in sync with current lease state. */
 460         if (lease->lease.lease_epoch != epoch) {
 461                 DEBUG(10,("%s: cancel outdated timeout\n", __func__));
 462                 TALLOC_FREE(lease->timeout);
 463         }
 464         lease->lease.lease_epoch = epoch;
 465         lease->lease.lease_state = current_state;
 466
 467         if (breaking) {
 468                 lease->lease.lease_flags |= SMB2_LEASE_FLAG_BREAK_IN_PROGRESS;
 469
 470                 if (lease->timeout == NULL) {
 471                         struct timeval t = timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0);
 472
 473                         DEBUG(10,("%s: setup timeout handler\n", __func__));
 474
 475                         lease->timeout = tevent_add_timer(lease->sconn->ev_ctx,
 476                                                           lease, t,
 477                                                           lease_timeout_handler,
 478                                                           lease);
 479                         if (lease->timeout == NULL) {
 480                                 DEBUG(0, ("%s: Could not add lease timeout handler\n",
 481                                           __func__));
 482                         }
 483                 }
 484         } else {
 485                 lease->lease.lease_flags &= ~SMB2_LEASE_FLAG_BREAK_IN_PROGRESS;
 486                 TALLOC_FREE(lease->timeout);
 487         }
 488
 489         return true;
 490 }
 491
 492 struct downgrade_lease_additional_state {
 493         struct tevent_immediate *im;
 494         struct smbXsrv_connection *xconn;
 495         uint32_t break_flags;
 496         struct smb2_lease_key lease_key;
 497         uint32_t break_from;
 498         uint32_t break_to;
 499         uint16_t new_epoch;
 500 };
 501
 502 static void downgrade_lease_additional_trigger(struct tevent_context *ev,
 503                                                struct tevent_immediate *im,
 504                                                void *private_data)
 505 {
 506         struct downgrade_lease_additional_state *state =
 507                 talloc_get_type_abort(private_data,
 508                 struct downgrade_lease_additional_state);
 509         struct smbXsrv_connection *xconn = state->xconn;
 510         NTSTATUS status;
 511
 512         status = smbd_smb2_send_lease_break(xconn,
 513                                             state->new_epoch,
 514                                             state->break_flags,
 515                                             &state->lease_key,
 516                                             state->break_from,
 517                                             state->break_to);
 518         TALLOC_FREE(state);
 519         if (!NT_STATUS_IS_OK(status)) {
 520                 smbd_server_connection_terminate(xconn,
 521                                                  nt_errstr(status));
 522                 return;
 523         }
 524 }
 525
 526 struct downgrade_lease_fsps_state {
 527         struct file_id id;
 528         struct share_mode_lock *lck;
 529         const struct smb2_lease_key *key;
 530 };
 531
 532 static struct files_struct *downgrade_lease_fsps(struct files_struct *fsp,
 533                                                  void *private_data)
 534 {
 535         struct downgrade_lease_fsps_state *state =
 536                 (struct downgrade_lease_fsps_state *)private_data;
 537
 538         if (fsp->oplock_type != LEASE_OPLOCK) {
 539                 return NULL;
 540         }
 541         if (!smb2_lease_key_equal(&fsp->lease->lease.lease_key, state->key)) {
 542                 return NULL;
 543         }
 544         if (!file_id_equal(&fsp->file_id, &state->id)) {
 545                 return NULL;
 546         }
 547
 548         fsp_lease_update(state->lck, fsp_client_guid(fsp), fsp->lease);
 549
 550         return NULL;
 551 }
 552
 553 NTSTATUS downgrade_lease(struct smbXsrv_connection *xconn,
 554                          uint32_t num_file_ids,
 555                          const struct file_id *ids,
 556                          const struct smb2_lease_key *key,
 557                          uint32_t lease_state)
 558 {
 559         struct smbd_server_connection *sconn = xconn->client->sconn;
 560         const struct GUID *client_guid = NULL;
 561         struct share_mode_lock *lck;
 562         const struct file_id id = ids[0];
 563         uint32_t current_state, breaking_to_requested, breaking_to_required;
 564         bool breaking;
 565         uint16_t lease_version, epoch;
 566         NTSTATUS status;
 567         uint32_t i;
 568
 569         DEBUG(10, ("%s: Downgrading %s to %x\n", __func__,
 570                    file_id_string_tos(&id), (unsigned)lease_state));
 571
 572         lck = get_existing_share_mode_lock(talloc_tos(), id);
 573         if (lck == NULL) {
 574                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 575         }
 576
 577         client_guid = &sconn->client->connections->smb2.client.guid;
 578
 579         status = leases_db_get(client_guid,
 580                                key,
 581                                &id,
 582                                &current_state,
 583                                &breaking,
 584                                &breaking_to_requested,
 585                                &breaking_to_required,
 586                                &lease_version,
 587                                &epoch);
 588         if (!NT_STATUS_IS_OK(status)) {
 589                 DBG_WARNING("leases_db_get returned %s\n",
 590                             nt_errstr(status));
 591                 TALLOC_FREE(lck);
 592                 return status;
 593         }
 594
 595         if (!breaking) {
 596                 DBG_WARNING("Attempt to break from %"PRIu32" to %"PRIu32" - "
 597                             "but we're not in breaking state\n",
 598                             current_state, lease_state);
 599                 TALLOC_FREE(lck);
 600                 return NT_STATUS_UNSUCCESSFUL;
 601         }
 602
 603         /*
 604          * Can't upgrade anything: breaking_to_requested (and current_state)
 605          * must be a strict bitwise superset of new_lease_state
 606          */
 607         if ((lease_state & breaking_to_requested) != lease_state) {
 608                 DBG_WARNING("Attempt to upgrade from %"PRIu32" to %"PRIu32" "
 609                             "- expected %"PRIu32"\n",
 610                             current_state, lease_state,
 611                             breaking_to_requested);
 612                 TALLOC_FREE(lck);
 613                 return NT_STATUS_REQUEST_NOT_ACCEPTED;
 614         }
 615
 616         if (current_state != lease_state) {
 617                 current_state = lease_state;
 618         }
 619
 620         status = NT_STATUS_OK;
 621
 622         if ((lease_state & ~breaking_to_required) != 0) {
 623                 struct downgrade_lease_additional_state *state;
 624
 625                 DBG_INFO("lease state %"PRIu32" not fully broken from "
 626                          "%"PRIu32" to %"PRIu32"\n",
 627                          lease_state,
 628                          current_state,
 629                          breaking_to_required);
 630
 631                 breaking_to_requested = breaking_to_required;
 632
 633                 if (current_state & (SMB2_LEASE_WRITE|SMB2_LEASE_HANDLE)) {
 634                         /*
 635                          * Here we break in steps, as windows does
 636                          * see the breaking3 and v2_breaking3 tests.
 637                          */
 638                         breaking_to_requested |= SMB2_LEASE_READ;
 639                 }
 640
 641                 state = talloc_zero(xconn,
 642                                     struct downgrade_lease_additional_state);
 643                 if (state == NULL) {
 644                         TALLOC_FREE(lck);
 645                         return NT_STATUS_NO_MEMORY;
 646                 }
 647
 648                 state->im = tevent_create_immediate(state);
 649                 if (state->im == NULL) {
 650                         TALLOC_FREE(state);
 651                         TALLOC_FREE(lck);
 652                         return NT_STATUS_NO_MEMORY;
 653                 }
 654
 655                 state->xconn = xconn;
 656                 state->lease_key = *key;
 657                 state->break_from = current_state;
 658                 state->break_to = breaking_to_requested;
 659                 if (lease_version > 1) {
 660                         state->new_epoch = epoch;
 661                 }
 662
 663                 if (current_state & (SMB2_LEASE_WRITE|SMB2_LEASE_HANDLE)) {
 664                         state->break_flags =
 665                                 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED;
 666                 } else {
 667                         /*
 668                          * This is an async break without
 669                          * SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED
 670                          *
 671                          * we need to store NONE state in the
 672                          * database.
 673                          */
 674                         current_state = 0;
 675                         breaking_to_requested = 0;
 676                         breaking_to_required = 0;
 677                         breaking = false;
 678
 679                         {
 680                                 NTSTATUS set_status;
 681
 682                                 set_status = leases_db_set(
 683                                         &sconn->client->connections->
 684                                         smb2.client.guid,
 685                                         key,
 686                                         current_state,
 687                                         breaking,
 688                                         breaking_to_requested,
 689                                         breaking_to_required,
 690                                         lease_version,
 691                                         epoch);
 692
 693                                 if (!NT_STATUS_IS_OK(set_status)) {
 694                                         DBG_DEBUG("leases_db_set failed: %s\n",
 695                                                   nt_errstr(set_status));
 696                                         return set_status;
 697                                 }
 698                         }
 699                 }
 700
 701                 tevent_schedule_immediate(state->im,
 702                                           xconn->client->raw_ev_ctx,
 703                                           downgrade_lease_additional_trigger,
 704                                           state);
 705
 706                 status = NT_STATUS_OPLOCK_BREAK_IN_PROGRESS;
 707         } else {
 708                 DBG_DEBUG("breaking from %"PRIu32" to %"PRIu32" - "
 709                           "expected %"PRIu32"\n",
 710                           current_state,
 711                           lease_state,
 712                           breaking_to_requested);
 713
 714                 breaking_to_requested = 0;
 715                 breaking_to_required = 0;
 716                 breaking = false;
 717         }
 718
 719         {
 720                 NTSTATUS set_status;
 721
 722                 set_status = leases_db_set(
 723                         client_guid,
 724                         key,
 725                         current_state,
 726                         breaking,
 727                         breaking_to_requested,
 728                         breaking_to_required,
 729                         lease_version,
 730                         epoch);
 731
 732                 if (!NT_STATUS_IS_OK(set_status)) {
 733                         DBG_DEBUG("leases_db_set failed: %s\n",
 734                                   nt_errstr(set_status));
 735                         TALLOC_FREE(lck);
 736                         return set_status;
 737                 }
 738         }
 739
 740         DEBUG(10, ("%s: Downgrading %s to %x => %s\n", __func__,
 741                    file_id_string_tos(&id), (unsigned)lease_state, nt_errstr(status)));
 742
 743         /*
 744          * No, we did not modify the share mode array. We did modify
 745          * the leases_db. But without this we don't notify a lease
 746          * break waiter via dbwrap_watch_record. We need to make
 747          * leases_db watched too.
 748          */
 749         lck->data->modified = true;
 750
 751         {
 752                 struct downgrade_lease_fsps_state state = {
 753                         .id = id, .lck = lck, .key = key,
 754                 };
 755
 756                 files_forall(sconn, downgrade_lease_fsps, &state);
 757         }
 758
 759         TALLOC_FREE(lck);
 760         DEBUG(10, ("%s: Downgrading %s to %x => %s\n", __func__,
 761                    file_id_string_tos(&id), (unsigned)lease_state, nt_errstr(status)));
 762
 763         /*
 764          * Dynamic share case. Ensure other opens are copies.
 765          * This will only be breaking to NONE.
 766          */
 767
 768         for (i = 1; i < num_file_ids; i++) {
 769                 lck = get_existing_share_mode_lock(talloc_tos(), ids[i]);
 770                 if (lck == NULL) {
 771                         return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 772                 }
 773
 774                 {
 775                         struct downgrade_lease_fsps_state state = {
 776                                 .id = ids[i], .lck = lck, .key = key,
 777                         };
 778
 779                         files_forall(sconn, downgrade_lease_fsps, &state);
 780                 }
 781
 782                 DEBUG(10, ("%s: Downgrading %s to %x => %s\n", __func__,
 783                         file_id_string_tos(&ids[i]), (unsigned)lease_state, nt_errstr(status)));
 784
 785                 TALLOC_FREE(lck);
 786         }
 787
 788         return status;
 789 }
 790
 791 /****************************************************************************
 792  Set up an oplock break message.
 793 ****************************************************************************/
 794
 795 #define SMB1_BREAK_MESSAGE_LENGTH (smb_size + 8*2)
 796
 797 static void new_break_message_smb1(files_struct *fsp, int cmd,
 798                                    char result[SMB1_BREAK_MESSAGE_LENGTH])
 799 {
 800         memset(result,'\0',smb_size);
 801         srv_set_message(result,8,0,true);
 802         SCVAL(result,smb_com,SMBlockingX);
 803         SSVAL(result,smb_tid,fsp->conn->cnum);
 804         SSVAL(result,smb_pid,0xFFFF);
 805         SSVAL(result,smb_uid,0);
 806         SSVAL(result,smb_mid,0xFFFF);
 807         SCVAL(result,smb_vwv0,0xFF);
 808         SSVAL(result,smb_vwv2,fsp->fnum);
 809         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 810         SCVAL(result,smb_vwv3+1,cmd);
 811 }
 812
 813 /****************************************************************************
 814  Function to do the waiting before sending a local break.
 815 ****************************************************************************/
 816
 817 static void wait_before_sending_break(void)
 818 {
 819         long wait_time = (long)lp_oplock_break_wait_time();
 820
 821         if (wait_time) {
 822                 smb_msleep(wait_time);
 823         }
 824 }
 825
 826 /****************************************************************************
 827  Ensure that we have a valid oplock.
 828 ****************************************************************************/
 829
 830 static files_struct *initial_break_processing(
 831         struct smbd_server_connection *sconn, struct file_id id,
 832         unsigned long file_id)
 833 {
 834         files_struct *fsp = NULL;
 835
 836         DEBUG(3, ("initial_break_processing: called for %s/%u\n"
 837                   "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 838                   file_id_string_tos(&id), (int)file_id,
 839                   sconn->oplocks.exclusive_open,
 840                   sconn->oplocks.level_II_open));
 841
 842         /*
 843          * We need to search the file open table for the
 844          * entry containing this dev and inode, and ensure
 845          * we have an oplock on it.
 846          */
 847
 848         fsp = file_find_dif(sconn, id, file_id);
 849
 850         if(fsp == NULL) {
 851                 /* The file could have been closed in the meantime - return success. */
 852                 DEBUG(3, ("initial_break_processing: cannot find open file "
 853                           "with file_id %s gen_id = %lu, allowing break to "
 854                           "succeed.\n", file_id_string_tos(&id), file_id));
 855                 return NULL;
 856         }
 857
 858         /* Ensure we have an oplock on the file */
 859
 860         /*
 861          * There is a potential race condition in that an oplock could
 862          * have been broken due to another udp request, and yet there are
 863          * still oplock break messages being sent in the udp message
 864          * queue for this file. So return true if we don't have an oplock,
 865          * as we may have just freed it.
 866          */
 867
 868         if(fsp->oplock_type == NO_OPLOCK) {
 869                 DEBUG(3, ("initial_break_processing: file %s (file_id = %s "
 870                           "gen_id = %lu) has no oplock. Allowing break to "
 871                           "succeed regardless.\n", fsp_str_dbg(fsp),
 872                           file_id_string_tos(&id), fsp->fh->gen_id));
 873                 return NULL;
 874         }
 875
 876         return fsp;
 877 }
 878
 879 static void oplock_timeout_handler(struct tevent_context *ctx,
 880                                    struct tevent_timer *te,
 881                                    struct timeval now,
 882                                    void *private_data)
 883 {
 884         files_struct *fsp = (files_struct *)private_data;
 885
 886         SMB_ASSERT(fsp->sent_oplock_break != NO_BREAK_SENT);
 887
 888         /* Remove the timed event handler. */
 889         TALLOC_FREE(fsp->oplock_timeout);
 890         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 891                   fsp_str_dbg(fsp)));
 892         remove_oplock(fsp);
 893 }
 894
 895 /*******************************************************************
 896  Add a timeout handler waiting for the client reply.
 897 *******************************************************************/
 898
 899 static void add_oplock_timeout_handler(files_struct *fsp)
 900 {
 901         if (fsp->oplock_timeout != NULL) {
 902                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 903                           "around\n"));
 904         }
 905
 906         fsp->oplock_timeout =
 907                 tevent_add_timer(fsp->conn->sconn->ev_ctx, fsp,
 908                                  timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 909                                  oplock_timeout_handler, fsp);
 910
 911         if (fsp->oplock_timeout == NULL) {
 912                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 913         }
 914 }
 915
 916 static void send_break_message_smb1(files_struct *fsp, int level)
 917 {
 918         struct smbXsrv_connection *xconn = NULL;
 919         char break_msg[SMB1_BREAK_MESSAGE_LENGTH];
 920
 921         /*
 922          * For SMB1 we only have one connection
 923          */
 924         xconn = fsp->conn->sconn->client->connections;
 925
 926         new_break_message_smb1(fsp, level, break_msg);
 927
 928         show_msg(break_msg);
 929         if (!srv_send_smb(xconn,
 930                         break_msg, false, 0,
 931                         IS_CONN_ENCRYPTED(fsp->conn),
 932                         NULL)) {
 933                 exit_server_cleanly("send_break_message_smb1: "
 934                         "srv_send_smb failed.");
 935         }
 936 }
 937
 938 /*******************************************************************
 939  This handles the generic oplock break message from another smbd.
 940 *******************************************************************/
 941
 942 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 943                                          void *private_data,
 944                                          uint32_t msg_type,
 945                                          struct server_id src,
 946                                          DATA_BLOB *data)
 947 {
 948         struct file_id id;
 949         struct share_mode_entry msg;
 950         files_struct *fsp;
 951         bool use_kernel;
 952         struct smbd_server_connection *sconn =
 953                 talloc_get_type_abort(private_data,
 954                 struct smbd_server_connection);
 955         struct server_id self = messaging_server_id(sconn->msg_ctx);
 956         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 957         uint16_t break_from;
 958         uint16_t break_to;
 959         bool break_needed = true;
 960         struct server_id_buf tmp;
 961
 962         if (data->data == NULL) {
 963                 DEBUG(0, ("Got NULL buffer\n"));
 964                 return;
 965         }
 966
 967         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 968                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 969                 return;
 970         }
 971
 972         /* De-linearize incoming message. */
 973         message_to_share_mode_entry(&id, &msg, (char *)data->data);
 974         break_to = msg.op_type;
 975
 976         DEBUG(10, ("Got oplock break to %u message from pid %s: %s/%llu\n",
 977                    (unsigned)break_to, server_id_str_buf(src, &tmp),
 978                    file_id_string_tos(&id),
 979                    (unsigned long long)msg.share_file_id));
 980
 981         fsp = initial_break_processing(sconn, id, msg.share_file_id);
 982
 983         if (fsp == NULL) {
 984                 /* We hit a race here. Break messages are sent, and before we
 985                  * get to process this message, we have closed the file. */
 986                 DEBUG(3, ("Did not find fsp\n"));
 987                 return;
 988         }
 989
 990         break_from = fsp_lease_type(fsp);
 991
 992         if (fsp->oplock_type != LEASE_OPLOCK) {
 993                 if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 994                         /*
 995                          * Nothing to do anymore
 996                          */
 997                         DEBUG(10, ("fsp->sent_oplock_break = %d\n",
 998                                    fsp->sent_oplock_break));
 999                         return;
1000                 }
1001         }
1002
1003         if (!(global_client_caps & CAP_LEVEL_II_OPLOCKS)) {
1004                 DEBUG(10, ("client_caps without level2 oplocks\n"));
1005                 break_to &= ~SMB2_LEASE_READ;
1006         }
1007
1008         use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) &&
1009                         (koplocks != NULL);
1010         if (use_kernel) {
1011                 DEBUG(10, ("Kernel oplocks don't allow level2\n"));
1012                 break_to &= ~SMB2_LEASE_READ;
1013         }
1014
1015         if (!lp_level2_oplocks(SNUM(fsp->conn))) {
1016                 DEBUG(10, ("no level2 oplocks by config\n"));
1017                 break_to &= ~SMB2_LEASE_READ;
1018         }
1019
1020         if (fsp->oplock_type == LEASE_OPLOCK) {
1021                 const struct GUID *client_guid = fsp_client_guid(fsp);
1022                 struct share_mode_lock *lck;
1023                 uint32_t current_state;
1024                 uint32_t breaking_to_requested, breaking_to_required;
1025                 bool breaking;
1026                 uint16_t lease_version, epoch;
1027                 NTSTATUS status;
1028
1029                 lck = get_existing_share_mode_lock(
1030                         talloc_tos(), fsp->file_id);
1031                 if (lck == NULL) {
1032                         /*
1033                          * We hit a race here. Break messages are sent, and
1034                          * before we get to process this message, we have closed
1035                          * the file.
1036                          */
1037                         DEBUG(3, ("Did not find share_mode\n"));
1038                         return;
1039                 }
1040
1041                 status = leases_db_get(client_guid,
1042                                        &fsp->lease->lease.lease_key,
1043                                        &id,
1044                                        &current_state,
1045                                        &breaking,
1046                                        &breaking_to_requested,
1047                                        &breaking_to_required,
1048                                        &lease_version,
1049                                        &epoch);
1050                 if (!NT_STATUS_IS_OK(status)) {
1051                         DBG_WARNING("leases_db_get returned %s\n",
1052                                     nt_errstr(status));
1053                         TALLOC_FREE(lck);
1054                         return;
1055                 }
1056
1057                 break_from = current_state;
1058                 break_to &= current_state;
1059
1060                 if (breaking) {
1061                         break_to &= breaking_to_required;
1062                         if (breaking_to_required != break_to) {
1063                                 /*
1064                                  * Note we don't increment the epoch
1065                                  * here, which might be a bug in
1066                                  * Windows too...
1067                                  */
1068                                 breaking_to_required = break_to;
1069                         }
1070                         break_needed = false;
1071                 } else if (current_state == break_to) {
1072                         break_needed = false;
1073                 } else if (current_state == SMB2_LEASE_READ) {
1074                         current_state = SMB2_LEASE_NONE;
1075                         /* Need to increment the epoch */
1076                         epoch += 1;
1077                 } else {
1078                         breaking = true;
1079                         breaking_to_required = break_to;
1080                         breaking_to_requested = break_to;
1081                         /* Need to increment the epoch */
1082                         epoch += 1;
1083                 }
1084
1085                 {
1086                         NTSTATUS set_status;
1087
1088                         set_status = leases_db_set(
1089                                 client_guid,
1090                                 &fsp->lease->lease.lease_key,
1091                                 current_state,
1092                                 breaking,
1093                                 breaking_to_requested,
1094                                 breaking_to_required,
1095                                 lease_version,
1096                                 epoch);
1097
1098                         if (!NT_STATUS_IS_OK(set_status)) {
1099                                 DBG_DEBUG("leases_db_set failed: %s\n",
1100                                           nt_errstr(set_status));
1101                                 return;
1102                         }
1103                 }
1104
1105                 /* Ensure we're in sync with current lease state. */
1106                 fsp_lease_update(lck, fsp_client_guid(fsp), fsp->lease);
1107
1108                 TALLOC_FREE(lck);
1109         }
1110
1111         if (!break_needed) {
1112                 DEBUG(10,("%s: skip break\n", __func__));
1113                 return;
1114         }
1115
1116         if ((break_from == SMB2_LEASE_NONE) && !break_needed) {
1117                 DEBUG(3, ("Already downgraded oplock to none on %s: %s\n",
1118                           file_id_string_tos(&fsp->file_id),
1119                           fsp_str_dbg(fsp)));
1120                 return;
1121         }
1122
1123         DEBUG(10, ("break_from=%u, break_to=%u\n",
1124                    (unsigned)break_from, (unsigned)break_to));
1125
1126         if ((break_from == break_to) && !break_needed) {
1127                 DEBUG(3, ("Already downgraded oplock to %u on %s: %s\n",
1128                           (unsigned)break_to,
1129                           file_id_string_tos(&fsp->file_id),
1130                           fsp_str_dbg(fsp)));
1131                 return;
1132         }
1133
1134         /* Need to wait before sending a break
1135            message if we sent ourselves this message. */
1136         if (serverid_equal(&self, &src)) {
1137                 wait_before_sending_break();
1138         }
1139
1140         if (sconn->using_smb2) {
1141                 send_break_message_smb2(fsp, break_from, break_to);
1142         } else {
1143                 send_break_message_smb1(fsp, (break_to & SMB2_LEASE_READ) ?
1144                                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
1145         }
1146
1147         if ((break_from == SMB2_LEASE_READ) &&
1148             (break_to == SMB2_LEASE_NONE)) {
1149                 /*
1150                  * This is an async break without a reply and thus no timeout
1151                  *
1152                  * leases are handled above.
1153                  */
1154                 if (fsp->oplock_type != LEASE_OPLOCK) {
1155                         remove_oplock(fsp);
1156                 }
1157                 return;
1158         }
1159         if (fsp->oplock_type == LEASE_OPLOCK) {
1160                 return;
1161         }
1162
1163         fsp->sent_oplock_break = (break_to & SMB2_LEASE_READ) ?
1164                 LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
1165
1166         add_oplock_timeout_handler(fsp);
1167 }
1168
1169 /*******************************************************************
1170  This handles the kernel oplock break message.
1171 *******************************************************************/
1172
1173 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
1174                                         void *private_data,
1175                                         uint32_t msg_type,
1176                                         struct server_id src,
1177                                         DATA_BLOB *data)
1178 {
1179         struct file_id id;
1180         unsigned long file_id;
1181         files_struct *fsp;
1182         struct smbd_server_connection *sconn =
1183                 talloc_get_type_abort(private_data,
1184                 struct smbd_server_connection);
1185         struct server_id_buf tmp;
1186
1187         if (data->data == NULL) {
1188                 DEBUG(0, ("Got NULL buffer\n"));
1189                 return;
1190         }
1191
1192         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
1193                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
1194                 return;
1195         }
1196
1197         /* Pull the data from the message. */
1198         pull_file_id_24((char *)data->data, &id);
1199         file_id = (unsigned long)IVAL(data->data, 24);
1200
1201         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
1202                    server_id_str_buf(src, &tmp), file_id_string_tos(&id),
1203                    (unsigned int)file_id));
1204
1205         fsp = initial_break_processing(sconn, id, file_id);
1206
1207         if (fsp == NULL) {
1208                 DEBUG(3, ("Got a kernel oplock break message for a file "
1209                           "I don't know about\n"));
1210                 return;
1211         }
1212
1213         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
1214                 /* This is ok, kernel oplocks come in completely async */
1215                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
1216                           "break reply\n"));
1217                 return;
1218         }
1219
1220         if (sconn->using_smb2) {
1221                 send_break_message_smb2(fsp, 0, OPLOCKLEVEL_NONE);
1222         } else {
1223                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
1224         }
1225
1226         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
1227
1228         add_oplock_timeout_handler(fsp);
1229 }
1230
1231 static bool file_has_read_oplocks(struct files_struct *fsp)
1232 {
1233         struct byte_range_lock *brl;
1234         uint32_t num_read_oplocks = 0;
1235
1236         brl = brl_get_locks_readonly(fsp);
1237         if (brl == NULL) {
1238                 return false;
1239         }
1240
1241         num_read_oplocks = brl_num_read_oplocks(brl);
1242
1243         DBG_DEBUG("num_read_oplocks = %"PRIu32"\n", num_read_oplocks);
1244
1245         return (num_read_oplocks != 0);
1246 }
1247
1248 struct break_to_none_state {
1249         struct smbd_server_connection *sconn;
1250         struct file_id id;
1251         struct smb2_lease_key lease_key;
1252         struct GUID client_guid;
1253 };
1254 static void do_break_to_none(struct tevent_context *ctx,
1255                              struct tevent_immediate *im,
1256                              void *private_data);
1257
1258 /****************************************************************************
1259  This function is called on any file modification or lock request. If a file
1260  is level 2 oplocked then it must tell all other level 2 holders to break to
1261  none.
1262 ****************************************************************************/
1263
1264 static void contend_level2_oplocks_begin_default(files_struct *fsp,
1265                                               enum level2_contention_type type)
1266 {
1267         struct smbd_server_connection *sconn = fsp->conn->sconn;
1268         struct tevent_immediate *im;
1269         struct break_to_none_state *state;
1270         bool has_read_oplocks;
1271
1272         /*
1273          * If this file is level II oplocked then we need
1274          * to grab the shared memory lock and inform all
1275          * other files with a level II lock that they need
1276          * to flush their read caches. We keep the lock over
1277          * the shared memory area whilst doing this.
1278          */
1279
1280         if (fsp_lease_type_is_exclusive(fsp)) {
1281                 /*
1282                  * There can't be any level2 oplocks, we're alone.
1283                  */
1284                 return;
1285         }
1286
1287         has_read_oplocks = file_has_read_oplocks(fsp);
1288         if (!has_read_oplocks) {
1289                 DEBUG(10, ("No read oplocks around\n"));
1290                 return;
1291         }
1292
1293         /*
1294          * When we get here we might have a brlock entry locked. Also
1295          * locking the share mode entry would violate the locking
1296          * order. Breaking level2 oplocks to none is asynchronous
1297          * anyway, so we postpone this into an immediate event.
1298          */
1299
1300         state = talloc(sconn, struct break_to_none_state);
1301         if (state == NULL) {
1302                 DEBUG(1, ("talloc failed\n"));
1303                 return;
1304         }
1305         *state = (struct break_to_none_state) {
1306                 .sconn = sconn, .id = fsp->file_id,
1307         };
1308
1309         if (fsp->oplock_type == LEASE_OPLOCK) {
1310                 state->client_guid = *fsp_client_guid(fsp);
1311                 state->lease_key = fsp->lease->lease.lease_key;
1312                 DEBUG(10, ("Breaking through lease key %"PRIu64"/%"PRIu64"\n",
1313                            state->lease_key.data[0],
1314                            state->lease_key.data[1]));
1315         }
1316
1317         im = tevent_create_immediate(state);
1318         if (im == NULL) {
1319                 DEBUG(1, ("tevent_create_immediate failed\n"));
1320                 TALLOC_FREE(state);
1321                 return;
1322         }
1323         tevent_schedule_immediate(im, sconn->ev_ctx, do_break_to_none, state);
1324 }
1325
1326 static void send_break_to_none(struct messaging_context *msg_ctx,
1327                                const struct file_id *id,
1328                                const struct share_mode_entry *e)
1329 {
1330         char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
1331
1332         share_mode_entry_to_message(msg, id, e);
1333         /* Overload entry->op_type */
1334         SSVAL(msg, OP_BREAK_MSG_OP_TYPE_OFFSET, NO_OPLOCK);
1335
1336         messaging_send_buf(msg_ctx, e->pid, MSG_SMB_BREAK_REQUEST,
1337                            (uint8_t *)msg, sizeof(msg));
1338 }
1339
1340 static bool do_break_lease_to_none(struct share_mode_lock *lck,
1341                                    struct share_mode_entry *e,
1342                                    void *private_data)
1343 {
1344         struct break_to_none_state *state = talloc_get_type_abort(
1345                 private_data, struct break_to_none_state);
1346         uint32_t current_state = 0;
1347         bool our_own;
1348         NTSTATUS status;
1349
1350         DBG_DEBUG("lease_key=%"PRIu64"/%"PRIu64"\n",
1351                   e->lease_key.data[0],
1352                   e->lease_key.data[1]);
1353
1354         status = leases_db_get(&e->client_guid,
1355                                &e->lease_key,
1356                                &state->id,
1357                                &current_state,
1358                                NULL, /* breaking */
1359                                NULL, /* breaking_to_requested */
1360                                NULL, /* breaking_to_required */
1361                                NULL, /* lease_version */
1362                                NULL); /* epoch */
1363         if (!NT_STATUS_IS_OK(status)) {
1364                 DBG_WARNING("leases_db_get failed: %s\n",
1365                             nt_errstr(status));
1366                 return false;
1367         }
1368
1369         if ((current_state & SMB2_LEASE_READ) == 0) {
1370                 return false;
1371         }
1372
1373         our_own = smb2_lease_equal(&state->client_guid,
1374                                    &state->lease_key,
1375                                    &e->client_guid,
1376                                    &e->lease_key);
1377         if (our_own) {
1378                 DEBUG(10, ("Don't break our own lease\n"));
1379                 return false;
1380         }
1381
1382         DBG_DEBUG("Breaking %"PRIu64"/%"PRIu64" to none\n",
1383                   e->lease_key.data[0],
1384                   e->lease_key.data[1]);
1385
1386         send_break_to_none(state->sconn->msg_ctx, &state->id, e);
1387
1388         return false;
1389 }
1390
1391 static void do_break_to_none(struct tevent_context *ctx,
1392                              struct tevent_immediate *im,
1393                              void *private_data)
1394 {
1395         struct break_to_none_state *state = talloc_get_type_abort(
1396                 private_data, struct break_to_none_state);
1397         uint32_t i;
1398         struct share_mode_lock *lck;
1399         struct share_mode_data *d;
1400         bool ok;
1401
1402         lck = get_existing_share_mode_lock(talloc_tos(), state->id);
1403         if (lck == NULL) {
1404                 DEBUG(1, ("%s: failed to lock share mode entry for file %s.\n",
1405                           __func__, file_id_string_tos(&state->id)));
1406                 goto done;
1407         }
1408         d = lck->data;
1409
1410         /*
1411          * Walk leases and oplocks separately: We have to send one break per
1412          * lease. If we have multiple share_mode_entry having a common lease,
1413          * we would break the lease twice if we don't walk the leases list
1414          * separately.
1415          */
1416
1417         ok = share_mode_forall_leases(lck, do_break_lease_to_none, state);
1418         if (!ok) {
1419                 DBG_WARNING("share_mode_forall_leases failed\n");
1420         }
1421
1422         for(i = 0; i < d->num_share_modes; i++) {
1423                 struct share_mode_entry *e = &d->share_modes[i];
1424
1425                 if (!is_valid_share_mode_entry(e)) {
1426                         continue;
1427                 }
1428                 if (e->op_type == LEASE_OPLOCK) {
1429                         /*
1430                          * Took care of those in the loop above
1431                          */
1432                         continue;
1433                 }
1434
1435                 /*
1436                  * As there could have been multiple writes waiting at the
1437                  * lock_share_entry gate we may not be the first to
1438                  * enter. Hence the state of the op_types in the share mode
1439                  * entries may be partly NO_OPLOCK and partly LEVEL_II
1440                  * oplock. It will do no harm to re-send break messages to
1441                  * those smbd's that are still waiting their turn to remove
1442                  * their LEVEL_II state, and also no harm to ignore existing
1443                  * NO_OPLOCK states. JRA.
1444                  */
1445
1446                 DEBUG(10, ("%s: share_entry[%i]->op_type == %d\n", __func__,
1447                            i, e->op_type ));
1448
1449                 if (e->op_type == NO_OPLOCK) {
1450                         continue;
1451                 }
1452
1453                 /* Paranoia .... */
1454                 if (EXCLUSIVE_OPLOCK_TYPE(e->op_type)) {
1455                         DEBUG(0,("%s: PANIC. "
1456                                  "share mode entry %d is an exclusive "
1457                                  "oplock !\n", __func__, i ));
1458                         TALLOC_FREE(lck);
1459                         abort();
1460                 }
1461
1462                 send_break_to_none(state->sconn->msg_ctx, &state->id, e);
1463         }
1464
1465         /* We let the message receivers handle removing the oplock state
1466            in the share mode lock db. */
1467
1468         TALLOC_FREE(lck);
1469 done:
1470         TALLOC_FREE(state);
1471         return;
1472 }
1473
1474 void smbd_contend_level2_oplocks_begin(files_struct *fsp,
1475                                   enum level2_contention_type type)
1476 {
1477         contend_level2_oplocks_begin_default(fsp, type);
1478 }
1479
1480 void smbd_contend_level2_oplocks_end(files_struct *fsp,
1481                                 enum level2_contention_type type)
1482 {
1483         return;
1484 }
1485
1486 /****************************************************************************
1487  Linearize a share mode entry struct to an internal oplock break message.
1488 ****************************************************************************/
1489
1490 void share_mode_entry_to_message(char *msg, const struct file_id *id,
1491                                  const struct share_mode_entry *e)
1492 {
1493         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32_t)e->pid.pid);
1494         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
1495         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
1496         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
1497         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
1498         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
1499         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
1500         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
1501         /*
1502          * "id" used to be part of share_mode_entry, thus the strange
1503          * place to put this. Feel free to move somewhere else :-)
1504          */
1505         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, id);
1506         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
1507         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
1508         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
1509         SIVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET,e->name_hash);
1510         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
1511 }
1512
1513 /****************************************************************************
1514  De-linearize an internal oplock break message to a share mode entry struct.
1515 ****************************************************************************/
1516
1517 void message_to_share_mode_entry(struct file_id *id,
1518                                  struct share_mode_entry *e,
1519                                  const char *msg)
1520 {
1521         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
1522         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
1523         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
1524         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
1525         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
1526         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
1527         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
1528         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
1529         /*
1530          * "id" used to be part of share_mode_entry, thus the strange
1531          * place to put this. Feel free to move somewhere else :-)
1532          */
1533         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, id);
1534         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
1535         e->uid = (uint32_t)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
1536         e->flags = (uint16_t)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
1537         e->name_hash = IVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET);
1538         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
1539 }
1540
1541 /****************************************************************************
1542  Setup oplocks for this process.
1543 ****************************************************************************/
1544
1545 bool init_oplocks(struct smbd_server_connection *sconn)
1546 {
1547         DEBUG(3,("init_oplocks: initializing messages.\n"));
1548
1549         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_REQUEST,
1550                            process_oplock_break_message);
1551         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_KERNEL_BREAK,
1552                            process_kernel_oplock_break);
1553         return true;
1554 }
1555
1556 void init_kernel_oplocks(struct smbd_server_connection *sconn)
1557 {
1558         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
1559
1560         /* only initialize once */
1561         if (koplocks == NULL) {
1562 #ifdef HAVE_KERNEL_OPLOCKS_LINUX
1563                 koplocks = linux_init_kernel_oplocks(sconn);
1564 #endif
1565                 sconn->oplocks.kernel_ops = koplocks;
1566         }
1567 }