reactos/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: handle.c,v 1.47 2003/07/10 21:34:29 royce Exp $
  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 #define NTOS_MODE_KERNEL
  33 #include <ntos.h>
  34 #include <internal/ob.h>
  35 #include <internal/ps.h>
  36 #include <internal/pool.h>
  37 #include <internal/safe.h>
  38
  39 #define NDEBUG
  40 #include <internal/debug.h>
  41
  42 /* TYPES *******************************************************************/
  43
  44 /*
  45  * PURPOSE: Defines a handle
  46  */
  47 typedef struct
  48 {
  49    PVOID ObjectBody;
  50    ACCESS_MASK GrantedAccess;
  51    BOOLEAN Inherit;
  52 } HANDLE_REP, *PHANDLE_REP;
  53
  54 #define HANDLE_BLOCK_ENTRIES ((PAGE_SIZE-sizeof(LIST_ENTRY))/sizeof(HANDLE_REP))
  55
  56
  57 /*
  58  * PURPOSE: Defines a page's worth of handles
  59  */
  60 typedef struct
  61 {
  62    LIST_ENTRY entry;
  63    HANDLE_REP handles[HANDLE_BLOCK_ENTRIES];
  64 } HANDLE_BLOCK, *PHANDLE_BLOCK;
  65
  66
  67 /* GLOBALS *******************************************************************/
  68
  69 #define TAG_HANDLE_TABLE    TAG('H', 'T', 'B', 'L')
  70
  71 /* FUNCTIONS ***************************************************************/
  72
  73
  74 static PHANDLE_REP ObpGetObjectByHandle(PHANDLE_TABLE HandleTable, HANDLE h)
  75 /*
  76  * FUNCTION: Get the data structure for a handle
  77  * ARGUMENTS:
  78  *         Process = Process to get the handle for
  79  *         h = Handle
  80  * ARGUMENTS: A pointer to the information about the handle on success,
  81  *            NULL on failure
  82  */
  83 {
  84    PLIST_ENTRY current;
  85    unsigned int handle = (((unsigned int)h) >> 2) - 1;
  86    unsigned int count=handle/HANDLE_BLOCK_ENTRIES;
  87    HANDLE_BLOCK* blk = NULL;
  88    unsigned int i;
  89
  90    DPRINT("ObpGetObjectByHandle(HandleTable %x, h %x)\n",HandleTable,h);
  91
  92    current = HandleTable->ListHead.Flink;
  93    DPRINT("current %x\n",current);
  94
  95    for (i=0;i<count;i++)
  96      {
  97         current = current->Flink;
  98         if (current == (&(HandleTable->ListHead)))
  99           {
 100              return(NULL);
 101           }
 102      }
 103
 104    blk = CONTAINING_RECORD(current,HANDLE_BLOCK,entry);
 105    DPRINT("object: %p\n",&(blk->handles[handle%HANDLE_BLOCK_ENTRIES]));
 106    return(&(blk->handles[handle%HANDLE_BLOCK_ENTRIES]));
 107 }
 108
 109 NTSTATUS
 110 ObDuplicateObject(PEPROCESS SourceProcess,
 111                   PEPROCESS TargetProcess,
 112                   HANDLE SourceHandle,
 113                   PHANDLE TargetHandle,
 114                   ACCESS_MASK DesiredAccess,
 115                   BOOLEAN InheritHandle,
 116                   ULONG Options)
 117 {
 118   KIRQL oldIrql;
 119   PHANDLE_REP SourceHandleRep;
 120   PVOID ObjectBody;
 121
 122   KeAcquireSpinLock(&SourceProcess->HandleTable.ListLock, &oldIrql);
 123   SourceHandleRep = ObpGetObjectByHandle(&SourceProcess->HandleTable,
 124                                          SourceHandle);
 125   if (SourceHandleRep == NULL)
 126     {
 127       KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 128       return(STATUS_INVALID_HANDLE);
 129     }
 130   ObjectBody = SourceHandleRep->ObjectBody;
 131   ObReferenceObjectByPointer(ObjectBody,
 132                              0,
 133                              NULL,
 134                              UserMode);
 135
 136   if (Options & DUPLICATE_SAME_ACCESS)
 137     {
 138       DesiredAccess = SourceHandleRep->GrantedAccess;
 139     }
 140
 141   KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 142   ObCreateHandle(TargetProcess,
 143                  ObjectBody,
 144                  DesiredAccess,
 145                  InheritHandle,
 146                  TargetHandle);
 147
 148   if (Options & DUPLICATE_CLOSE_SOURCE)
 149     {
 150       ZwClose(SourceHandle);
 151     }
 152
 153   ObDereferenceObject(ObjectBody);
 154   return(STATUS_SUCCESS);
 155 }
 156
 157 /*
 158  * @implemented
 159  */
 160 NTSTATUS STDCALL
 161 NtDuplicateObject (IN   HANDLE          SourceProcessHandle,
 162                    IN   HANDLE          SourceHandle,
 163                    IN   HANDLE          TargetProcessHandle,
 164                    OUT  PHANDLE         UnsafeTargetHandle,
 165                    IN   ACCESS_MASK     DesiredAccess,
 166                    IN   BOOLEAN         InheritHandle,
 167                    ULONG                Options)
 168 /*
 169  * FUNCTION: Copies a handle from one process space to another
 170  * ARGUMENTS:
 171  *         SourceProcessHandle = The source process owning the handle. The
 172  *                               source process should have opened
 173  *                               the SourceHandle with PROCESS_DUP_HANDLE
 174  *                               access.
 175  *         SourceHandle = The handle to the object.
 176  *         TargetProcessHandle = The destination process owning the handle
 177  *         TargetHandle (OUT) = Caller should supply storage for the
 178  *                              duplicated handle.
 179  *         DesiredAccess = The desired access to the handle.
 180  *         InheritHandle = Indicates wheter the new handle will be inheritable
 181  *                         or not.
 182  *         Options = Specifies special actions upon duplicating the handle.
 183  *                   Can be one of the values DUPLICATE_CLOSE_SOURCE |
 184  *                   DUPLICATE_SAME_ACCESS. DUPLICATE_CLOSE_SOURCE specifies
 185  *                   that the source handle should be closed after duplicating.
 186  *                   DUPLICATE_SAME_ACCESS specifies to ignore the
 187  *                   DesiredAccess paramter and just grant the same access to
 188  *                   the new handle.
 189  * RETURNS: Status
 190  * REMARKS: This function maps to the win32 DuplicateHandle.
 191  */
 192 {
 193    PEPROCESS SourceProcess;
 194    PEPROCESS TargetProcess;
 195    PHANDLE_REP SourceHandleRep;
 196    KIRQL oldIrql;
 197    PVOID ObjectBody;
 198    HANDLE TargetHandle;
 199    NTSTATUS Status;
 200
 201    ASSERT_IRQL(PASSIVE_LEVEL);
 202
 203    Status = ObReferenceObjectByHandle(SourceProcessHandle,
 204                                       PROCESS_DUP_HANDLE,
 205                                       NULL,
 206                                       UserMode,
 207                                       (PVOID*)&SourceProcess,
 208                                       NULL);
 209    if (!NT_SUCCESS(Status))
 210      {
 211        return(Status);
 212      }
 213    Status = ObReferenceObjectByHandle(TargetProcessHandle,
 214                                       PROCESS_DUP_HANDLE,
 215                                       NULL,
 216                                       UserMode,
 217                                       (PVOID*)&TargetProcess,
 218                                       NULL);
 219    if (!NT_SUCCESS(Status))
 220      {
 221        ObDereferenceObject(SourceProcess);
 222        return(Status);
 223      }
 224
 225    /* Check for magic handle first */
 226    if (SourceHandle == NtCurrentThread())
 227      {
 228        ObReferenceObjectByHandle(SourceHandle,
 229                                  PROCESS_DUP_HANDLE,
 230                                  NULL,
 231                                  UserMode,
 232                                  &ObjectBody,
 233                                  NULL);
 234
 235        ObCreateHandle(TargetProcess,
 236                       ObjectBody,
 237                       THREAD_ALL_ACCESS,
 238                       InheritHandle,
 239                       &TargetHandle);
 240      }
 241    else
 242      {
 243        KeAcquireSpinLock(&SourceProcess->HandleTable.ListLock, &oldIrql);
 244        SourceHandleRep = ObpGetObjectByHandle(&SourceProcess->HandleTable,
 245                                               SourceHandle);
 246        if (SourceHandleRep == NULL)
 247          {
 248            KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 249            ObDereferenceObject(SourceProcess);
 250            ObDereferenceObject(TargetProcess);
 251            return(STATUS_INVALID_HANDLE);
 252          }
 253        ObjectBody = SourceHandleRep->ObjectBody;
 254        ObReferenceObjectByPointer(ObjectBody,
 255                                   0,
 256                                   NULL,
 257                                   UserMode);
 258
 259        if (Options & DUPLICATE_SAME_ACCESS)
 260          {
 261            DesiredAccess = SourceHandleRep->GrantedAccess;
 262          }
 263
 264        KeReleaseSpinLock(&SourceProcess->HandleTable.ListLock, oldIrql);
 265        if (!SourceHandleRep->Inherit)
 266          {
 267            ObDereferenceObject(TargetProcess);
 268            ObDereferenceObject(SourceProcess);
 269            ObDereferenceObject(ObjectBody);
 270            return STATUS_INVALID_HANDLE;
 271          }
 272        ObCreateHandle(TargetProcess,
 273                       ObjectBody,
 274                       DesiredAccess,
 275                       InheritHandle,
 276                       &TargetHandle);
 277      }
 278
 279    if (Options & DUPLICATE_CLOSE_SOURCE)
 280      {
 281         ZwClose(SourceHandle);
 282      }
 283
 284    ObDereferenceObject(TargetProcess);
 285    ObDereferenceObject(SourceProcess);
 286    ObDereferenceObject(ObjectBody);
 287
 288    Status = MmCopyToCaller(UnsafeTargetHandle, &TargetHandle, sizeof(HANDLE));
 289    if (!NT_SUCCESS(Status))
 290      {
 291        return(Status);
 292      }
 293
 294    return(STATUS_SUCCESS);
 295 }
 296
 297 VOID ObCloseAllHandles(PEPROCESS Process)
 298 {
 299    KIRQL oldIrql;
 300    PHANDLE_TABLE HandleTable;
 301    PLIST_ENTRY current_entry;
 302    PHANDLE_BLOCK current;
 303    ULONG i;
 304    PVOID ObjectBody;
 305    BOOLEAN IsProcessHandle;
 306
 307    DPRINT("ObCloseAllHandles(Process %x)\n", Process);
 308
 309    HandleTable = &Process->HandleTable;
 310
 311    KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 312
 313    current_entry = HandleTable->ListHead.Flink;
 314
 315    while (current_entry != &HandleTable->ListHead)
 316      {
 317         current = CONTAINING_RECORD(current_entry, HANDLE_BLOCK, entry);
 318
 319         for (i = 0; i < HANDLE_BLOCK_ENTRIES; i++)
 320           {
 321              ObjectBody = current->handles[i].ObjectBody;
 322
 323              if (ObjectBody != NULL)
 324                {
 325                   POBJECT_HEADER Header = BODY_TO_HEADER(ObjectBody);
 326
 327                   if (Header->ObjectType == PsProcessType ||
 328                       Header->ObjectType == PsThreadType)
 329                     {
 330                        DPRINT("Deleting handle to %x\n", ObjectBody);
 331                     }
 332
 333                   ObReferenceObjectByPointer(ObjectBody,
 334                                              0,
 335                                              NULL,
 336                                              UserMode);
 337                   InterlockedDecrement(&Header->HandleCount);
 338                   current->handles[i].ObjectBody = NULL;
 339
 340                   KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 341
 342                   if (Header->ObjectType == PsProcessType)
 343                   {
 344                      IsProcessHandle = TRUE;
 345                      KeDetachProcess();
 346                   }
 347                   else
 348                   {
 349                      IsProcessHandle = FALSE;
 350                   }
 351                   if ((Header->ObjectType != NULL) &&
 352                       (Header->ObjectType->Close != NULL))
 353                     {
 354                        Header->ObjectType->Close(ObjectBody,
 355                                                  Header->HandleCount);
 356                     }
 357
 358                   ObDereferenceObject(ObjectBody);
 359                   if (IsProcessHandle)
 360                   {
 361                      KeAttachProcess(Process);
 362                   }
 363                   KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 364                   current_entry = &HandleTable->ListHead;
 365                   break;
 366                }
 367           }
 368
 369         current_entry = current_entry->Flink;
 370      }
 371    KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 372    DPRINT("ObCloseAllHandles() finished\n");
 373    DPRINT("Type %x\n", BODY_TO_HEADER(Process)->ObjectType);
 374 }
 375
 376 VOID ObDeleteHandleTable(PEPROCESS Process)
 377 /*
 378  * FUNCTION: Deletes the handle table associated with a process
 379  */
 380 {
 381    PLIST_ENTRY current = NULL;
 382    PHANDLE_TABLE HandleTable = NULL;
 383
 384    ObCloseAllHandles(Process);
 385
 386    HandleTable = &Process->HandleTable;
 387    current = RemoveHeadList(&HandleTable->ListHead);
 388
 389    while (current != &HandleTable->ListHead)
 390      {
 391         HANDLE_BLOCK* HandleBlock = CONTAINING_RECORD(current,
 392                                                       HANDLE_BLOCK,
 393                                                       entry);
 394         DPRINT("Freeing %x\n", HandleBlock);
 395         ExFreePool(HandleBlock);
 396
 397         current = RemoveHeadList(&HandleTable->ListHead);
 398      }
 399 }
 400
 401
 402 VOID ObCreateHandleTable(PEPROCESS Parent,
 403                          BOOLEAN Inherit,
 404                          PEPROCESS Process)
 405 /*
 406  * FUNCTION: Creates a handle table for a process
 407  * ARGUMENTS:
 408  *       Parent = Parent process (or NULL if this is the first process)
 409  *       Inherit = True if the process should inherit its parent's handles
 410  *       Process = Process whose handle table is to be created
 411  */
 412 {
 413    PHANDLE_TABLE ParentHandleTable, HandleTable;
 414    KIRQL oldIrql;
 415    PLIST_ENTRY parent_current;
 416    ULONG i;
 417    PHANDLE_BLOCK current_block, new_block;
 418
 419    DPRINT("ObCreateHandleTable(Parent %x, Inherit %d, Process %x)\n",
 420           Parent,Inherit,Process);
 421
 422    InitializeListHead(&(Process->HandleTable.ListHead));
 423    KeInitializeSpinLock(&(Process->HandleTable.ListLock));
 424
 425    if (Parent != NULL)
 426      {
 427         ParentHandleTable = &Parent->HandleTable;
 428         HandleTable = &Process->HandleTable;
 429
 430         KeAcquireSpinLock(&Parent->HandleTable.ListLock, &oldIrql);
 431         KeAcquireSpinLockAtDpcLevel(&Process->HandleTable.ListLock);
 432
 433         parent_current = ParentHandleTable->ListHead.Flink;
 434
 435         while (parent_current != &ParentHandleTable->ListHead)
 436           {
 437              current_block = CONTAINING_RECORD(parent_current,
 438                                                HANDLE_BLOCK,
 439                                                entry);
 440              new_block = ExAllocatePoolWithTag(NonPagedPool,
 441                                                sizeof(HANDLE_BLOCK),
 442                                                TAG_HANDLE_TABLE);
 443              if (new_block == NULL)
 444              {
 445                 break;
 446              }
 447              RtlZeroMemory(new_block, sizeof(HANDLE_BLOCK));
 448
 449              for (i=0; i<HANDLE_BLOCK_ENTRIES; i++)
 450              {
 451                 if (current_block->handles[i].ObjectBody)
 452                 {
 453                    if (current_block->handles[i].Inherit && Inherit)
 454                    {
 455                       new_block->handles[i].ObjectBody =
 456                         current_block->handles[i].ObjectBody;
 457                       new_block->handles[i].GrantedAccess =
 458                         current_block->handles[i].GrantedAccess;
 459                       new_block->handles[i].Inherit = TRUE;
 460                       InterlockedIncrement(&(BODY_TO_HEADER(current_block->handles[i].ObjectBody)->HandleCount));
 461                    }
 462                 }
 463              }
 464              InsertTailList(&Process->HandleTable.ListHead, &new_block->entry);
 465              parent_current = parent_current->Flink;
 466           }
 467         KeReleaseSpinLockFromDpcLevel(&Process->HandleTable.ListLock);
 468         KeReleaseSpinLock(&Parent->HandleTable.ListLock, oldIrql);
 469      }
 470 }
 471
 472
 473 PVOID ObDeleteHandle(PEPROCESS Process, HANDLE Handle)
 474 {
 475    PHANDLE_REP Rep;
 476    PVOID ObjectBody;
 477    KIRQL oldIrql;
 478    PHANDLE_TABLE HandleTable;
 479    POBJECT_HEADER Header;
 480
 481    DPRINT("ObDeleteHandle(Handle %x)\n",Handle);
 482
 483    HandleTable = &Process->HandleTable;
 484
 485    KeAcquireSpinLock(&HandleTable->ListLock, &oldIrql);
 486
 487    Rep = ObpGetObjectByHandle(HandleTable, Handle);
 488    if (Rep == NULL)
 489      {
 490         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 491         return(NULL);
 492      }
 493
 494    ObjectBody = Rep->ObjectBody;
 495    DPRINT("ObjectBody %x\n", ObjectBody);
 496    if (ObjectBody != NULL)
 497      {
 498         Header = BODY_TO_HEADER(ObjectBody);
 499         InterlockedDecrement(&(BODY_TO_HEADER(ObjectBody)->HandleCount));
 500         ObReferenceObjectByPointer(ObjectBody,
 501                                    0,
 502                                    NULL,
 503                                    UserMode);
 504         Rep->ObjectBody = NULL;
 505
 506         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 507
 508         if ((Header->ObjectType != NULL) &&
 509             (Header->ObjectType->Close != NULL))
 510           {
 511              Header->ObjectType->Close(ObjectBody, Header->HandleCount);
 512           }
 513      }
 514    else
 515      {
 516         KeReleaseSpinLock(&HandleTable->ListLock, oldIrql);
 517      }
 518
 519    DPRINT("Finished ObDeleteHandle()\n");
 520    return(ObjectBody);
 521 }
 522
 523
 524 NTSTATUS ObCreateHandle(PEPROCESS Process,
 525                         PVOID ObjectBody,
 526                         ACCESS_MASK GrantedAccess,
 527                         BOOLEAN Inherit,
 528                         PHANDLE HandleReturn)
 529 /*
 530  * FUNCTION: Add a handle referencing an object
 531  * ARGUMENTS:
 532  *         obj = Object body that the handle should refer to
 533  * RETURNS: The created handle
 534  * NOTE: The handle is valid only in the context of the current process
 535  */
 536 {
 537    LIST_ENTRY* current;
 538    unsigned int handle=1;
 539    unsigned int i;
 540    HANDLE_BLOCK* new_blk = NULL;
 541    PHANDLE_TABLE HandleTable;
 542    KIRQL oldlvl;
 543
 544    DPRINT("ObCreateHandle(Process %x, obj %x)\n",Process,ObjectBody);
 545
 546    assert(Process);
 547
 548    if (ObjectBody != NULL)
 549      {
 550         InterlockedIncrement(&(BODY_TO_HEADER(ObjectBody)->HandleCount));
 551      }
 552    HandleTable = &Process->HandleTable;
 553    KeAcquireSpinLock(&HandleTable->ListLock, &oldlvl);
 554    current = HandleTable->ListHead.Flink;
 555    /*
 556     * Scan through the currently allocated handle blocks looking for a free
 557     * slot
 558     */
 559    while (current != (&HandleTable->ListHead))
 560      {
 561         HANDLE_BLOCK* blk = CONTAINING_RECORD(current,HANDLE_BLOCK,entry);
 562
 563         DPRINT("Current %x\n",current);
 564
 565         for (i=0;i<HANDLE_BLOCK_ENTRIES;i++)
 566           {
 567              DPRINT("Considering slot %d containing %x\n",i,blk->handles[i]);
 568              if (blk->handles[i].ObjectBody==NULL)
 569                {
 570                   blk->handles[i].ObjectBody = ObjectBody;
 571                   blk->handles[i].GrantedAccess = GrantedAccess;
 572                   blk->handles[i].Inherit = Inherit;
 573                   KeReleaseSpinLock(&HandleTable->ListLock, oldlvl);
 574                   *HandleReturn = (HANDLE)((handle + i) << 2);
 575                   return(STATUS_SUCCESS);
 576                }
 577           }
 578
 579         handle = handle + HANDLE_BLOCK_ENTRIES;
 580         current = current->Flink;
 581      }
 582
 583    /*
 584     * Add a new handle block to the end of the list
 585     */
 586    new_blk =
 587      (HANDLE_BLOCK *)ExAllocatePoolWithTag(NonPagedPool,sizeof(HANDLE_BLOCK),
 588                                            TAG_HANDLE_TABLE);
 589    if (!new_blk)
 590     {
 591       *HandleReturn = (PHANDLE)NULL;
 592       return(STATUS_INSUFFICIENT_RESOURCES);
 593     }
 594    RtlZeroMemory(new_blk,sizeof(HANDLE_BLOCK));
 595    InsertTailList(&(Process->HandleTable.ListHead),
 596                   &new_blk->entry);
 597    new_blk->handles[0].ObjectBody = ObjectBody;
 598    new_blk->handles[0].GrantedAccess = GrantedAccess;
 599    new_blk->handles[0].Inherit = Inherit;
 600    KeReleaseSpinLock(&HandleTable->ListLock, oldlvl);
 601    *HandleReturn = (HANDLE)(handle << 2);
 602    return(STATUS_SUCCESS);
 603 }
 604
 605
 606 /*
 607  * @implemented
 608  */
 609 NTSTATUS STDCALL
 610 ObReferenceObjectByHandle(HANDLE Handle,
 611                           ACCESS_MASK DesiredAccess,
 612                           POBJECT_TYPE ObjectType,
 613                           KPROCESSOR_MODE AccessMode,
 614                           PVOID* Object,
 615                           POBJECT_HANDLE_INFORMATION HandleInformationPtr)
 616 /*
 617  * FUNCTION: Increments the reference count for an object and returns a
 618  * pointer to its body
 619  * ARGUMENTS:
 620  *         Handle = Handle for the object
 621  *         DesiredAccess = Desired access to the object
 622  *         ObjectType
 623  *         AccessMode
 624  *         Object (OUT) = Points to the object body on return
 625  *         HandleInformation (OUT) = Contains information about the handle
 626  *                                   on return
 627  * RETURNS: Status
 628  */
 629 {
 630    PHANDLE_REP HandleRep;
 631    POBJECT_HEADER ObjectHeader;
 632    KIRQL oldIrql;
 633    PVOID ObjectBody;
 634    ACCESS_MASK GrantedAccess;
 635    NTSTATUS Status;
 636
 637    ASSERT_IRQL(PASSIVE_LEVEL);
 638
 639    DPRINT("ObReferenceObjectByHandle(Handle %x, DesiredAccess %x, "
 640            "ObjectType %x, AccessMode %d, Object %x)\n",Handle,DesiredAccess,
 641            ObjectType,AccessMode,Object);
 642
 643
 644    /*
 645     * Handle special handle names
 646     */
 647    if (Handle == NtCurrentProcess() &&
 648        (ObjectType == PsProcessType || ObjectType == NULL))
 649      {
 650         DPRINT("Reference from %x\n", ((PULONG)&Handle)[-1]);
 651
 652         Status = ObReferenceObjectByPointer(PsGetCurrentProcess(),
 653                                             PROCESS_ALL_ACCESS,
 654                                             PsProcessType,
 655                                             UserMode);
 656         if (! NT_SUCCESS(Status))
 657           {
 658             return Status;
 659           }
 660
 661         *Object = PsGetCurrentProcess();
 662         DPRINT("Referencing current process %x\n", PsGetCurrentProcess());
 663         return STATUS_SUCCESS;
 664      }
 665    else if (Handle == NtCurrentProcess())
 666      {
 667         CHECKPOINT;
 668         return(STATUS_OBJECT_TYPE_MISMATCH);
 669      }
 670    if (Handle == NtCurrentThread() &&
 671        (ObjectType == PsThreadType || ObjectType == NULL))
 672      {
 673         Status = ObReferenceObjectByPointer(PsGetCurrentThread(),
 674                                             THREAD_ALL_ACCESS,
 675                                             PsThreadType,
 676                                             UserMode);
 677         if (! NT_SUCCESS(Status))
 678           {
 679             return Status;
 680           }
 681
 682         *Object = PsGetCurrentThread();
 683         CHECKPOINT;
 684         return STATUS_SUCCESS;
 685      }
 686    else if (Handle == NtCurrentThread())
 687      {
 688         CHECKPOINT;
 689         return(STATUS_OBJECT_TYPE_MISMATCH);
 690      }
 691
 692    KeAcquireSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 693                      &oldIrql);
 694    HandleRep = ObpGetObjectByHandle(&PsGetCurrentProcess()->HandleTable,
 695                                     Handle);
 696    if (HandleRep == NULL || HandleRep->ObjectBody == NULL)
 697      {
 698         KeReleaseSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 699                           oldIrql);
 700         return(STATUS_INVALID_HANDLE);
 701      }
 702    ObjectBody = HandleRep->ObjectBody;
 703    DPRINT("ObjectBody %p\n",ObjectBody);
 704    ObjectHeader = BODY_TO_HEADER(ObjectBody);
 705    DPRINT("ObjectHeader->RefCount %lu\n",ObjectHeader->RefCount);
 706    ObReferenceObjectByPointer(ObjectBody,
 707                               0,
 708                               NULL,
 709                               UserMode);
 710    GrantedAccess = HandleRep->GrantedAccess;
 711    KeReleaseSpinLock(&PsGetCurrentProcess()->HandleTable.ListLock,
 712                      oldIrql);
 713
 714    ObjectHeader = BODY_TO_HEADER(ObjectBody);
 715    DPRINT("ObjectHeader->RefCount %lu\n",ObjectHeader->RefCount);
 716
 717    if (ObjectType != NULL && ObjectType != ObjectHeader->ObjectType)
 718      {
 719         CHECKPOINT;
 720         return(STATUS_OBJECT_TYPE_MISMATCH);
 721      }
 722
 723    if (ObjectHeader->ObjectType == PsProcessType)
 724      {
 725         DPRINT("Reference from %x\n", ((PULONG)&Handle)[-1]);
 726      }
 727
 728    if (DesiredAccess && AccessMode == UserMode)
 729      {
 730         RtlMapGenericMask(&DesiredAccess, ObjectHeader->ObjectType->Mapping);
 731
 732         if (!(GrantedAccess & DesiredAccess) &&
 733             !((~GrantedAccess) & DesiredAccess))
 734           {
 735              CHECKPOINT;
 736              return(STATUS_ACCESS_DENIED);
 737           }
 738      }
 739
 740    *Object = ObjectBody;
 741
 742    CHECKPOINT;
 743    return(STATUS_SUCCESS);
 744 }
 745
 746
 747 /**********************************************************************
 748  * NAME                                                 EXPORTED
 749  *      NtClose
 750  *
 751  * DESCRIPTION
 752  *      Closes a handle reference to an object.
 753  *
 754  * ARGUMENTS
 755  *      Handle
 756  *              Handle to close.
 757  *
 758  * RETURN VALUE
 759  *      Status.
 760  *
 761  * @implemented
 762  */
 763 NTSTATUS STDCALL NtClose(HANDLE Handle)
 764 {
 765    PVOID                ObjectBody;
 766    POBJECT_HEADER       Header;
 767
 768    assert_irql(PASSIVE_LEVEL);
 769
 770    DPRINT("NtClose(Handle %x)\n",Handle);
 771
 772    ObjectBody = ObDeleteHandle(PsGetCurrentProcess(), Handle);
 773    if (ObjectBody == NULL)
 774      {
 775         return(STATUS_INVALID_HANDLE);
 776      }
 777
 778    Header = BODY_TO_HEADER(ObjectBody);
 779
 780    DPRINT("Dereferencing %x\n", ObjectBody);
 781    ObDereferenceObject(ObjectBody);
 782
 783    return(STATUS_SUCCESS);
 784 }
 785
 786 /*
 787  * @implemented
 788  */
 789 NTSTATUS STDCALL
 790 ObInsertObject(PVOID Object,
 791                PACCESS_STATE PassedAccessState,
 792                ACCESS_MASK DesiredAccess,
 793                ULONG AdditionalReferences,
 794                PVOID* ReferencedObject,
 795                PHANDLE Handle)
 796 {
 797   return(ObCreateHandle(PsGetCurrentProcess(),
 798                         Object,
 799                         DesiredAccess,
 800                         FALSE,
 801                         Handle));
 802 }
 803
 804 /* EOF */