ntoskrnl/ob/handle.c

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 1998, 1999, 2000, 2001 ReactOS Team
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19 /* $Id$
  20  *
  21  * COPYRIGHT:          See COPYING in the top level directory
  22  * PROJECT:            ReactOS kernel
  23  * FILE:               ntoskrnl/ob/handle.c
  24  * PURPOSE:            Managing handles
  25  * PROGRAMMER:         David Welch (welch@cwcom.net)
  26  * REVISION HISTORY:
  27  *                 17/06/98: Created
  28  */
  29
  30 /* INCLUDES ****************************************************************/
  31
  32 #include <ddk/ntddk.h>
  33 #include <internal/ob.h>
  34 #include <internal/ps.h>
  35 #include <internal/pool.h>
  36 #include <internal/safe.h>
  37
  38 #define NDEBUG
  39 #include <internal/debug.h>
  40
  41 /* TYPES *******************************************************************/
  42
  43 /*
  44  * PURPOSE: Defines a handle
  45  */
  46 typedef struct
  47 {
  48    PVOID ObjectBody;
  49    ACCESS_MASK GrantedAccess;
  50    BOOLEAN Inherit;
  51 } HANDLE_REP, *PHANDLE_REP;
  52
  53 #define HANDLE_BLOCK_ENTRIES ((PAGE_SIZE-sizeof(LIST_ENTRY))/sizeof(HANDLE_REP))
  54
  55
  56 /*
  57  * PURPOSE: Defines a page's worth of handles
  58  */
  59 typedef struct
  60 {
  61    LIST_ENTRY entry;
  62    HANDLE_REP handles[HANDLE_BLOCK_ENTRIES];
  63 } HANDLE_BLOCK, *PHANDLE_BLOCK;
  64
  65
  66 /* GLOBALS *******************************************************************/
  67
  68 #define TAG_HANDLE_TABLE    TAG('H', 'T', 'B', 'L')
  69
  70 /* FUNCTIONS ***************************************************************/
  71
  72
  73 static PHANDLE_REP ObpGetObjectByHandle(PHANDLE_TABLE HandleTable, HANDLE h)
  74 /*
  75  * FUNCTION: Get the data structure for a handle
  76  * ARGUMENTS:
  77  *         Process = Process to get the handle for
  78  *         h = Handle
  79  * ARGUMENTS: A pointer to the information about the handle on success,
  80  *            NULL on failure
  81  */
  82 {
  83    PLIST_ENTRY current;
  84    unsigned int handle = (((unsigned int)h) >> 2) - 1;
  85    unsigned int count=handle/HANDLE_BLOCK_ENTRIES;
  86    HANDLE_BLOCK* blk = NULL;
  87    unsigned int i;
  88
  89    DPRINT("ObpGetObjectByHandle(HandleTable %x, h %x)\n",HandleTable,h);
  90
  91    current = HandleTable->ListHead.Flink;
  92    DPRINT("current %x\n",current);
  93
  94    for (i=0;i<count;i++)
  95      {
  96         current = current->Flink;
  97         if (current == (&(HandleTable->ListHead)))
  98           {
  99              return(NULL);
 100           }
 101      }
 102
 103    blk = CONTAINING_RECORD(current,HANDLE_BLOCK,entry);
 104    DPRINT("object: %p\n",&(blk->handles[handle%HANDLE_BLOCK_ENTRIES]));
 105    return(&(blk->handles[handle%HANDLE_BLOCK_ENTRIES]));
 106 }
 107
 108 NTSTATUS
 109 ObDuplicateObject(PEPROCESS SourceProcess,
 110                   PEPROCESS TargetProcess,
 111                   HANDLE SourceHandle,
 112                   PHANDLE TargetHandle,
 113                   ACCESS_MASK DesiredAccess,
 114                   BOOLEAN InheritHandle,
 115                   ULONG Options)
 116 {
 117   KIRQL oldIrql;
 118   PHANDLE_REP SourceHandleRep;
 119   PVOID ObjectBody;
 120
 121   KeAcquireSpinLock(&SourceProcess->HandleTable.ListLock, &oldIrql);
 122   SourceHandleRep = ObpGetObjectByHandle(&SourceProcess->HandleTable,
 123                                          SourceHandle);
 124   if (SourceHandleRep == NULL)
 125     {
 126       KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 127       return(STATUS_INVALID_HANDLE);
 128     }
 129   ObjectBody = SourceHandleRep->ObjectBody;
 130   ObReferenceObjectByPointer(ObjectBody,
 131                              0,
 132                              NULL,
 133                              UserMode);
 134
 135   if (Options & DUPLICATE_SAME_ACCESS)
 136     {
 137       DesiredAccess = SourceHandleRep->GrantedAccess;
 138     }
 139
 140   KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 141   ObCreateHandle(TargetProcess,
 142                  ObjectBody,
 143                  DesiredAccess,
 144                  InheritHandle,
 145                  TargetHandle);
 146
 147   if (Options & DUPLICATE_CLOSE_SOURCE)
 148     {
 149       ZwClose(SourceHandle);
 150     }
 151
 152   ObDereferenceObject(ObjectBody);
 153   return(STATUS_SUCCESS);
 154 }
 155
 156 NTSTATUS STDCALL
 157 NtDuplicateObject (IN   HANDLE          SourceProcessHandle,
 158                    IN   HANDLE          SourceHandle,
 159                    IN   HANDLE          TargetProcessHandle,
 160                    OUT  PHANDLE         UnsafeTargetHandle,
 161                    IN   ACCESS_MASK     DesiredAccess,
 162                    IN   BOOLEAN         InheritHandle,
 163                    ULONG                Options)
 164 /*
 165  * FUNCTION: Copies a handle from one process space to another
 166  * ARGUMENTS:
 167  *         SourceProcessHandle = The source process owning the handle. The
 168  *                               source process should have opened
 169  *                               the SourceHandle with PROCESS_DUP_HANDLE
 170  *                               access.
 171  *         SourceHandle = The handle to the object.
 172  *         TargetProcessHandle = The destination process owning the handle
 173  *         TargetHandle (OUT) = Caller should supply storage for the
 174  *                              duplicated handle.
 175  *         DesiredAccess = The desired access to the handle.
 176  *         InheritHandle = Indicates wheter the new handle will be inheritable
 177  *                         or not.
 178  *         Options = Specifies special actions upon duplicating the handle.
 179  *                   Can be one of the values DUPLICATE_CLOSE_SOURCE |
 180  *                   DUPLICATE_SAME_ACCESS. DUPLICATE_CLOSE_SOURCE specifies
 181  *                   that the source handle should be closed after duplicating.
 182  *                   DUPLICATE_SAME_ACCESS specifies to ignore the
 183  *                   DesiredAccess paramter and just grant the same access to
 184  *                   the new handle.
 185  * RETURNS: Status
 186  * REMARKS: This function maps to the win32 DuplicateHandle.
 187  */
 188 {
 189    PEPROCESS SourceProcess;
 190    PEPROCESS TargetProcess;
 191    PHANDLE_REP SourceHandleRep;
 192    KIRQL oldIrql;
 193    PVOID ObjectBody;
 194    HANDLE TargetHandle;
 195    NTSTATUS Status;
 196
 197    ASSERT_IRQL(PASSIVE_LEVEL);
 198
 199    Status = ObReferenceObjectByHandle(SourceProcessHandle,
 200                                       PROCESS_DUP_HANDLE,
 201                                       NULL,
 202                                       UserMode,
 203                                       (PVOID*)&SourceProcess,
 204                                       NULL);
 205    if (!NT_SUCCESS(Status))
 206      {
 207        return(Status);
 208      }
 209    Status = ObReferenceObjectByHandle(TargetProcessHandle,
 210                                       PROCESS_DUP_HANDLE,
 211                                       NULL,
 212                                       UserMode,
 213                                       (PVOID*)&TargetProcess,
 214                                       NULL);
 215    if (!NT_SUCCESS(Status))
 216      {
 217        ObDereferenceObject(SourceProcess);
 218        return(Status);
 219      }
 220    KeAcquireSpinLock(&SourceProcess->HandleTable.ListLock, &oldIrql);
 221    SourceHandleRep = ObpGetObjectByHandle(&SourceProcess->HandleTable,
 222                                           SourceHandle);
 223    if (SourceHandleRep == NULL)
 224      {
 225         KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 226         ObDereferenceObject(SourceProcess);
 227         ObDereferenceObject(TargetProcess);
 228         return(STATUS_INVALID_HANDLE);
 229      }
 230    ObjectBody = SourceHandleRep->ObjectBody;
 231    ObReferenceObjectByPointer(ObjectBody,
 232                               0,
 233                               NULL,
 234                               UserMode);
 235
 236    if (Options & DUPLICATE_SAME_ACCESS)
 237      {
 238         DesiredAccess = SourceHandleRep->GrantedAccess;
 239      }
 240
 241    KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 242    if (!SourceHandleRep->Inherit)
 243      {
 244        ObDereferenceObject(TargetProcess);
 245        ObDereferenceObject(SourceProcess);
 246        ObDereferenceObject(ObjectBody);
 247        return STATUS_INVALID_HANDLE;
 248      }
 249    ObCreateHandle(TargetProcess,
 250                   ObjectBody,
 251                   DesiredAccess,
 252                   InheritHandle,
 253                   &TargetHandle);
 254
 255    if (Options & DUPLICATE_CLOSE_SOURCE)
 256      {
 257         ZwClose(SourceHandle);
 258      }
 259
 260    ObDereferenceObject(TargetProcess);
 261    ObDereferenceObject(SourceProcess);
 262    ObDereferenceObject(ObjectBody);
 263
 264    Status = MmCopyToCaller(UnsafeTargetHandle, &TargetHandle, sizeof(HANDLE));
 265    if (!NT_SUCCESS(Status))
 266      {
 267        return(Status);
 268      }
 269
 270    return(STATUS_SUCCESS);
 271 }
 272
 273 VOID ObCloseAllHandles(PEPROCESS Process)
 274 {
 275    KIRQL oldIrql;
 276    PHANDLE_TABLE HandleTable;
 277    PLIST_ENTRY current_entry;
 278    PHANDLE_BLOCK current;
 279    ULONG i;
 280    PVOID ObjectBody;
 281
 282    DPRINT("ObCloseAllHandles(Process %x)\n", Process);
 283
 284    HandleTable = &Process->HandleTable;
 285
 286    KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 287
 288    current_entry = HandleTable->ListHead.Flink;
 289
 290    while (current_entry != &HandleTable->ListHead)
 291      {
 292         current = CONTAINING_RECORD(current_entry, HANDLE_BLOCK, entry);
 293
 294         for (i = 0; i < HANDLE_BLOCK_ENTRIES; i++)
 295           {
 296              ObjectBody = current->handles[i].ObjectBody;
 297
 298              if (ObjectBody != NULL)
 299                {
 300                   POBJECT_HEADER Header = BODY_TO_HEADER(ObjectBody);
 301
 302                   if (Header->ObjectType == PsProcessType ||
 303                       Header->ObjectType == PsThreadType)
 304                     {
 305                        DPRINT("Deleting handle to %x\n", ObjectBody);
 306                     }
 307
 308                   ObReferenceObjectByPointer(ObjectBody,
 309                                              0,
 310                                              NULL,
 311                                              UserMode);
 312                   InterlockedDecrement(&Header->HandleCount);
 313                   current->handles[i].ObjectBody = NULL;
 314
 315                   KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 316                   KeDetachProcess();
 317
 318                   if ((Header->ObjectType != NULL) &&
 319                       (Header->ObjectType->Close != NULL))
 320                     {
 321                        Header->ObjectType->Close(ObjectBody,
 322                                                  Header->HandleCount);
 323                     }
 324
 325                   ObDereferenceObject(ObjectBody);
 326                   KeAttachProcess(Process);
 327                   KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 328                   current_entry = &HandleTable->ListHead;
 329                   break;
 330                }
 331           }
 332
 333         current_entry = current_entry->Flink;
 334      }
 335    KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 336    DPRINT("ObCloseAllHandles() finished\n");
 337    DPRINT("Type %x\n", BODY_TO_HEADER(Process)->ObjectType);
 338 }
 339
 340 VOID ObDeleteHandleTable(PEPROCESS Process)
 341 /*
 342  * FUNCTION: Deletes the handle table associated with a process
 343  */
 344 {
 345    PLIST_ENTRY current = NULL;
 346    PHANDLE_TABLE HandleTable = NULL;
 347
 348    ObCloseAllHandles(Process);
 349
 350    HandleTable = &Process->HandleTable;
 351    current = RemoveHeadList(&HandleTable->ListHead);
 352
 353    while (current != &HandleTable->ListHead)
 354      {
 355         HANDLE_BLOCK* HandleBlock = CONTAINING_RECORD(current,
 356                                                       HANDLE_BLOCK,
 357                                                       entry);
 358         DPRINT("Freeing %x\n", HandleBlock);
 359         ExFreePool(HandleBlock);
 360
 361         current = RemoveHeadList(&HandleTable->ListHead);
 362      }
 363 }
 364
 365
 366 VOID ObCreateHandleTable(PEPROCESS Parent,
 367                          BOOLEAN Inherit,
 368                          PEPROCESS Process)
 369 /*
 370  * FUNCTION: Creates a handle table for a process
 371  * ARGUMENTS:
 372  *       Parent = Parent process (or NULL if this is the first process)
 373  *       Inherit = True if the process should inherit its parent's handles
 374  *       Process = Process whose handle table is to be created
 375  */
 376 {
 377    PHANDLE_TABLE ParentHandleTable, HandleTable;
 378    KIRQL oldIrql;
 379    PLIST_ENTRY parent_current;
 380    ULONG i;
 381    PHANDLE_BLOCK current_block, new_block;
 382
 383    DPRINT("ObCreateHandleTable(Parent %x, Inherit %d, Process %x)\n",
 384           Parent,Inherit,Process);
 385
 386    InitializeListHead(&(Process->HandleTable.ListHead));
 387    KeInitializeSpinLock(&(Process->HandleTable.ListLock));
 388
 389    if (Parent != NULL)
 390      {
 391         ParentHandleTable = &Parent->HandleTable;
 392         HandleTable = &Process->HandleTable;
 393
 394         KeAcquireSpinLock(&Parent->HandleTable.ListLock, &oldIrql);
 395         KeAcquireSpinLockAtDpcLevel(&Process->HandleTable.ListLock);
 396
 397         parent_current = ParentHandleTable->ListHead.Flink;
 398
 399         while (parent_current != &ParentHandleTable->ListHead)
 400           {
 401              current_block = CONTAINING_RECORD(parent_current,
 402                                                HANDLE_BLOCK,
 403                                                entry);
 404              new_block = ExAllocatePoolWithTag(NonPagedPool,
 405                                                sizeof(HANDLE_BLOCK),
 406                                                TAG_HANDLE_TABLE);
 407              if (new_block == NULL)
 408              {
 409                 break;
 410              }
 411              RtlZeroMemory(new_block, sizeof(HANDLE_BLOCK));
 412
 413              for (i=0; i<HANDLE_BLOCK_ENTRIES; i++)
 414              {
 415                 if (current_block->handles[i].ObjectBody)
 416                 {
 417                    if (current_block->handles[i].Inherit && Inherit)
 418                    {
 419                       new_block->handles[i].ObjectBody =
 420                         current_block->handles[i].ObjectBody;
 421                       new_block->handles[i].GrantedAccess =
 422                         current_block->handles[i].GrantedAccess;
 423                       new_block->handles[i].Inherit = TRUE;
 424                       InterlockedIncrement(&(BODY_TO_HEADER(current_block->handles[i].ObjectBody)->HandleCount));
 425                    }
 426                 }
 427              }
 428              InsertTailList(&Process->HandleTable.ListHead, &new_block->entry);
 429              parent_current = parent_current->Flink;
 430           }
 431         KeReleaseSpinLockFromDpcLevel(&Process->HandleTable.ListLock);
 432         KeReleaseSpinLock(&Parent->HandleTable.ListLock, oldIrql);
 433      }
 434 }
 435
 436
 437 PVOID ObDeleteHandle(PEPROCESS Process, HANDLE Handle)
 438 {
 439    PHANDLE_REP Rep;
 440    PVOID ObjectBody;
 441    KIRQL oldIrql;
 442    PHANDLE_TABLE HandleTable;
 443    POBJECT_HEADER Header;
 444
 445    DPRINT("ObDeleteHandle(Handle %x)\n",Handle);
 446
 447    HandleTable = &Process->HandleTable;
 448
 449    KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 450
 451    Rep = ObpGetObjectByHandle(HandleTable, Handle);
 452    if (Rep == NULL)
 453      {
 454         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 455         return(NULL);
 456      }
 457
 458    ObjectBody = Rep->ObjectBody;
 459    DPRINT("ObjectBody %x\n", ObjectBody);
 460    if (ObjectBody != NULL)
 461      {
 462         Header = BODY_TO_HEADER(ObjectBody);
 463         InterlockedDecrement(&(BODY_TO_HEADER(ObjectBody)->HandleCount));
 464         ObReferenceObjectByPointer(ObjectBody,
 465                                    0,
 466                                    NULL,
 467                                    UserMode);
 468         Rep->ObjectBody = NULL;
 469
 470         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 471
 472         if ((Header->ObjectType != NULL) &&
 473             (Header->ObjectType->Close != NULL))
 474           {
 475              Header->ObjectType->Close(ObjectBody, Header->HandleCount);
 476           }
 477      }
 478    else
 479      {
 480         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 481      }
 482
 483    DPRINT("Finished ObDeleteHandle()\n");
 484    return(ObjectBody);
 485 }
 486
 487
 488 NTSTATUS ObCreateHandle(PEPROCESS Process,
 489                         PVOID ObjectBody,
 490                         ACCESS_MASK GrantedAccess,
 491                         BOOLEAN Inherit,
 492                         PHANDLE HandleReturn)
 493 /*
 494  * FUNCTION: Add a handle referencing an object
 495  * ARGUMENTS:
 496  *         obj = Object body that the handle should refer to
 497  * RETURNS: The created handle
 498  * NOTE: The handle is valid only in the context of the current process
 499  */
 500 {
 501    LIST_ENTRY* current;
 502    unsigned int handle=1;
 503    unsigned int i;
 504    HANDLE_BLOCK* new_blk = NULL;
 505    PHANDLE_TABLE HandleTable;
 506    KIRQL oldlvl;
 507
 508    DPRINT("ObCreateHandle(Process %x, obj %x)\n",Process,ObjectBody);
 509
 510    assert(Process);
 511
 512    if (ObjectBody != NULL)
 513      {
 514         InterlockedIncrement(&(BODY_TO_HEADER(ObjectBody)->HandleCount));
 515      }
 516    HandleTable = &Process->HandleTable;
 517    KeAcquireSpinLock(&HandleTable->ListLock, &oldlvl);
 518    current = HandleTable->ListHead.Flink;
 519    /*
 520     * Scan through the currently allocated handle blocks looking for a free
 521     * slot
 522     */
 523    while (current != (&HandleTable->ListHead))
 524      {
 525         HANDLE_BLOCK* blk = CONTAINING_RECORD(current,HANDLE_BLOCK,entry);
 526
 527         DPRINT("Current %x\n",current);
 528
 529         for (i=0;i<HANDLE_BLOCK_ENTRIES;i++)
 530           {
 531              DPRINT("Considering slot %d containing %x\n",i,blk->handles[i]);
 532              if (blk->handles[i].ObjectBody==NULL)
 533                {
 534                   blk->handles[i].ObjectBody = ObjectBody;
 535                   blk->handles[i].GrantedAccess = GrantedAccess;
 536                   blk->handles[i].Inherit = Inherit;
 537                   KeReleaseSpinLock(&HandleTable->ListLock, oldlvl);
 538                   *HandleReturn = (HANDLE)((handle + i) << 2);
 539                   return(STATUS_SUCCESS);
 540                }
 541           }
 542
 543         handle = handle + HANDLE_BLOCK_ENTRIES;
 544         current = current->Flink;
 545      }
 546
 547    /*
 548     * Add a new handle block to the end of the list
 549     */
 550    new_blk =
 551      (HANDLE_BLOCK *)ExAllocatePoolWithTag(NonPagedPool,sizeof(HANDLE_BLOCK),
 552                                            TAG_HANDLE_TABLE);
 553    if (!new_blk)
 554     {
 555       *HandleReturn = (PHANDLE)NULL;
 556       return(STATUS_INSUFFICIENT_RESOURCES);
 557     }
 558    RtlZeroMemory(new_blk,sizeof(HANDLE_BLOCK));
 559    InsertTailList(&(Process->HandleTable.ListHead),
 560                   &new_blk->entry);
 561    new_blk->handles[0].ObjectBody = ObjectBody;
 562    new_blk->handles[0].GrantedAccess = GrantedAccess;
 563    new_blk->handles[0].Inherit = Inherit;
 564    KeReleaseSpinLock(&HandleTable->ListLock, oldlvl);
 565    *HandleReturn = (HANDLE)(handle << 2);
 566    return(STATUS_SUCCESS);
 567 }
 568
 569
 570 NTSTATUS STDCALL
 571 ObReferenceObjectByHandle(HANDLE Handle,
 572                           ACCESS_MASK DesiredAccess,
 573                           POBJECT_TYPE ObjectType,
 574                           KPROCESSOR_MODE AccessMode,
 575                           PVOID* Object,
 576                           POBJECT_HANDLE_INFORMATION HandleInformationPtr)
 577 /*
 578  * FUNCTION: Increments the reference count for an object and returns a
 579  * pointer to its body
 580  * ARGUMENTS:
 581  *         Handle = Handle for the object
 582  *         DesiredAccess = Desired access to the object
 583  *         ObjectType
 584  *         AccessMode
 585  *         Object (OUT) = Points to the object body on return
 586  *         HandleInformation (OUT) = Contains information about the handle
 587  *                                   on return
 588  * RETURNS: Status
 589  */
 590 {
 591    PHANDLE_REP HandleRep;
 592    POBJECT_HEADER ObjectHeader;
 593    KIRQL oldIrql;
 594    PVOID ObjectBody;
 595    ACCESS_MASK GrantedAccess;
 596
 597    ASSERT_IRQL(PASSIVE_LEVEL);
 598
 599    DPRINT("ObReferenceObjectByHandle(Handle %x, DesiredAccess %x, "
 600            "ObjectType %x, AccessMode %d, Object %x)\n",Handle,DesiredAccess,
 601            ObjectType,AccessMode,Object);
 602
 603
 604    /*
 605     * Handle special handle names
 606     */
 607    if (Handle == NtCurrentProcess() &&
 608        (ObjectType == PsProcessType || ObjectType == NULL))
 609      {
 610         DPRINT("Reference from %x\n", ((PULONG)&Handle)[-1]);
 611
 612         ObReferenceObjectByPointer(PsGetCurrentProcess(),
 613                                    PROCESS_ALL_ACCESS,
 614                                    PsProcessType,
 615                                    UserMode);
 616         *Object = PsGetCurrentProcess();
 617         DPRINT("Referencing current process %x\n", PsGetCurrentProcess());
 618         return(STATUS_SUCCESS);
 619      }
 620    else if (Handle == NtCurrentProcess())
 621      {
 622         CHECKPOINT;
 623         return(STATUS_OBJECT_TYPE_MISMATCH);
 624      }
 625    if (Handle == NtCurrentThread() &&
 626        (ObjectType == PsThreadType || ObjectType == NULL))
 627      {
 628         ObReferenceObjectByPointer(PsGetCurrentThread(),
 629                                    THREAD_ALL_ACCESS,
 630                                    PsThreadType,
 631                                    UserMode);
 632         *Object = PsGetCurrentThread();
 633         CHECKPOINT;
 634         return(STATUS_SUCCESS);
 635      }
 636    else if (Handle == NtCurrentThread())
 637      {
 638         CHECKPOINT;
 639         return(STATUS_OBJECT_TYPE_MISMATCH);
 640      }
 641
 642    KeAcquireSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 643                      &oldIrql);
 644    HandleRep = ObpGetObjectByHandle(&PsGetCurrentProcess()->HandleTable,
 645                                     Handle);
 646    if (HandleRep == NULL || HandleRep->ObjectBody == NULL)
 647      {
 648         KeReleaseSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 649                           oldIrql);
 650         return(STATUS_INVALID_HANDLE);
 651      }
 652    ObjectBody = HandleRep->ObjectBody;
 653    DPRINT("ObjectBody %p\n",ObjectBody);
 654    ObjectHeader = BODY_TO_HEADER(ObjectBody);
 655    DPRINT("ObjectHeader->RefCount %lu\n",ObjectHeader->RefCount);
 656    ObReferenceObjectByPointer(ObjectBody,
 657                               0,
 658                               NULL,
 659                               UserMode);
 660    GrantedAccess = HandleRep->GrantedAccess;
 661    KeReleaseSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 662                      oldIrql);
 663
 664    ObjectHeader = BODY_TO_HEADER(ObjectBody);
 665    DPRINT("ObjectHeader->RefCount %lu\n",ObjectHeader->RefCount);
 666
 667    if (ObjectType != NULL && ObjectType != ObjectHeader->ObjectType)
 668      {
 669         CHECKPOINT;
 670         return(STATUS_OBJECT_TYPE_MISMATCH);
 671      }
 672
 673    if (ObjectHeader->ObjectType == PsProcessType)
 674      {
 675         DPRINT("Reference from %x\n", ((PULONG)&Handle)[-1]);
 676      }
 677
 678    if (AccessMode == UserMode)
 679      {
 680         RtlMapGenericMask(&DesiredAccess, ObjectHeader->ObjectType->Mapping);
 681
 682         if (!(GrantedAccess & DesiredAccess) &&
 683             !((~GrantedAccess) & DesiredAccess))
 684           {
 685              CHECKPOINT;
 686              return(STATUS_ACCESS_DENIED);
 687           }
 688      }
 689
 690    *Object = ObjectBody;
 691
 692    CHECKPOINT;
 693    return(STATUS_SUCCESS);
 694 }
 695
 696
 697 /**********************************************************************
 698  * NAME                                                 EXPORTED
 699  *      NtClose
 700  *
 701  * DESCRIPTION
 702  *      Closes a handle reference to an object.
 703  *
 704  * ARGUMENTS
 705  *      Handle
 706  *              Handle to close.
 707  *
 708  * RETURN VALUE
 709  *      Status.
 710  */
 711 NTSTATUS STDCALL NtClose(HANDLE Handle)
 712 {
 713    PVOID                ObjectBody;
 714    POBJECT_HEADER       Header;
 715
 716    assert_irql(PASSIVE_LEVEL);
 717
 718    DPRINT("NtClose(Handle %x)\n",Handle);
 719
 720    ObjectBody = ObDeleteHandle(PsGetCurrentProcess(), Handle);
 721    if (ObjectBody == NULL)
 722      {
 723         return(STATUS_INVALID_HANDLE);
 724      }
 725
 726    Header = BODY_TO_HEADER(ObjectBody);
 727
 728    DPRINT("Dereferencing %x\n", ObjectBody);
 729    ObDereferenceObject(ObjectBody);
 730
 731    return(STATUS_SUCCESS);
 732 }
 733
 734 NTSTATUS STDCALL
 735 ObInsertObject(PVOID Object,
 736                PACCESS_STATE PassedAccessState,
 737                ACCESS_MASK DesiredAccess,
 738                ULONG AdditionalReferences,
 739                PVOID* ReferencedObject,
 740                PHANDLE Handle)
 741 {
 742   return(ObCreateHandle(PsGetCurrentProcess(),
 743                         Object,
 744                         DesiredAccess,
 745                         FALSE,
 746                         Handle));
 747 }
 748
 749 /* EOF */