reactos/drivers/filesystems/ntfs/mft.c

   1 /*
   2  *  ReactOS kernel
   3  *  Copyright (C) 2002 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  18  *
  19  * COPYRIGHT:        See COPYING in the top level directory
  20  * PROJECT:          ReactOS kernel
  21  * FILE:             drivers/filesystem/ntfs/mft.c
  22  * PURPOSE:          NTFS filesystem driver
  23  * PROGRAMMER:       Eric Kohl
  24  *                   Updated by Valentin Verkhovsky  2003/09/12
  25  */
  26
  27 /* INCLUDES *****************************************************************/
  28
  29 #include "ntfs.h"
  30
  31 #define NDEBUG
  32 #include <debug.h>
  33
  34 UNICODE_STRING IndexOfFileNames = RTL_CONSTANT_STRING(L"$I30");
  35
  36 /* FUNCTIONS ****************************************************************/
  37
  38 PNTFS_ATTR_CONTEXT
  39 PrepareAttributeContext(PNTFS_ATTR_RECORD AttrRecord)
  40 {
  41     PNTFS_ATTR_CONTEXT Context;
  42
  43     Context = ExAllocatePoolWithTag(NonPagedPool,
  44                                     FIELD_OFFSET(NTFS_ATTR_CONTEXT, Record) + AttrRecord->Length,
  45                                     TAG_NTFS);
  46     RtlCopyMemory(&Context->Record, AttrRecord, AttrRecord->Length);
  47     if (AttrRecord->IsNonResident)
  48     {
  49         LONGLONG DataRunOffset;
  50         ULONGLONG DataRunLength;
  51
  52         Context->CacheRun = (PUCHAR)&Context->Record + Context->Record.NonResident.MappingPairsOffset;
  53         Context->CacheRunOffset = 0;
  54         Context->CacheRun = DecodeRun(Context->CacheRun, &DataRunOffset, &DataRunLength);
  55         Context->CacheRunLength = DataRunLength;
  56         if (DataRunOffset != -1)
  57         {
  58             /* Normal run. */
  59             Context->CacheRunStartLCN =
  60             Context->CacheRunLastLCN = DataRunOffset;
  61         }
  62         else
  63         {
  64             /* Sparse run. */
  65             Context->CacheRunStartLCN = -1;
  66             Context->CacheRunLastLCN = 0;
  67         }
  68         Context->CacheRunCurrentOffset = 0;
  69     }
  70
  71     return Context;
  72 }
  73
  74
  75 VOID
  76 ReleaseAttributeContext(PNTFS_ATTR_CONTEXT Context)
  77 {
  78     ExFreePoolWithTag(Context, TAG_NTFS);
  79 }
  80
  81
  82 PNTFS_ATTR_CONTEXT
  83 FindAttributeHelper(PDEVICE_EXTENSION Vcb,
  84                     PNTFS_ATTR_RECORD AttrRecord,
  85                     PNTFS_ATTR_RECORD AttrRecordEnd,
  86                     ULONG Type,
  87                     const WCHAR *Name,
  88                     ULONG NameLength)
  89 {
  90     DPRINT("FindAttributeHelper(%p, %p, %p, 0x%x, %s, %u)\n", Vcb, AttrRecord, AttrRecordEnd, Type, Name, NameLength);
  91
  92     while (AttrRecord < AttrRecordEnd)
  93     {
  94         DPRINT("AttrRecord->Type = 0x%x\n", AttrRecord->Type);
  95
  96         if (AttrRecord->Type == AttributeEnd)
  97             break;
  98
  99         if (AttrRecord->Type == AttributeAttributeList)
 100         {
 101             PNTFS_ATTR_CONTEXT Context;
 102             PNTFS_ATTR_CONTEXT ListContext;
 103             PVOID ListBuffer;
 104             ULONGLONG ListSize;
 105             PNTFS_ATTR_RECORD ListAttrRecord;
 106             PNTFS_ATTR_RECORD ListAttrRecordEnd;
 107
 108             // Do not handle non-resident yet
 109             ASSERT(!(AttrRecord->IsNonResident & 1));
 110
 111             ListContext = PrepareAttributeContext(AttrRecord);
 112
 113             ListSize = AttributeDataLength(&ListContext->Record);
 114             if(ListSize <= 0xFFFFFFFF)
 115                 ListBuffer = ExAllocatePoolWithTag(NonPagedPool, (ULONG)ListSize, TAG_NTFS);
 116             else
 117                 ListBuffer = NULL;
 118
 119             if(!ListBuffer)
 120             {
 121                 DPRINT("Failed to allocate memory: %x\n", (ULONG)ListSize);
 122                 continue;
 123             }
 124
 125             ListAttrRecord = (PNTFS_ATTR_RECORD)ListBuffer;
 126             ListAttrRecordEnd = (PNTFS_ATTR_RECORD)((PCHAR)ListBuffer + ListSize);
 127
 128             if (ReadAttribute(Vcb, ListContext, 0, ListBuffer, (ULONG)ListSize) == ListSize)
 129             {
 130                 Context = FindAttributeHelper(Vcb, ListAttrRecord, ListAttrRecordEnd,
 131                                               Type, Name, NameLength);
 132
 133                 ReleaseAttributeContext(ListContext);
 134                 ExFreePoolWithTag(ListBuffer, TAG_NTFS);
 135
 136                 if (Context != NULL)
 137                 {
 138                     DPRINT("Found context = %p\n", Context);
 139                     return Context;
 140                 }
 141             }
 142         }
 143
 144         if (AttrRecord->Type == Type)
 145         {
 146             DPRINT("%d, %d\n", AttrRecord->NameLength, NameLength);
 147             if (AttrRecord->NameLength == NameLength)
 148             {
 149                 PWCHAR AttrName;
 150
 151                 AttrName = (PWCHAR)((PCHAR)AttrRecord + AttrRecord->NameOffset);
 152                 DPRINT("%s, %s\n", AttrName, Name);
 153                 if (RtlCompareMemory(AttrName, Name, NameLength << 1) == (NameLength << 1))
 154                 {
 155                     /* Found it, fill up the context and return. */
 156                     DPRINT("Found context\n");
 157                     return PrepareAttributeContext(AttrRecord);
 158                 }
 159             }
 160         }
 161
 162         if (AttrRecord->Length == 0)
 163         {
 164             DPRINT("Null length attribute record\n");
 165             return NULL;
 166         }
 167         AttrRecord = (PNTFS_ATTR_RECORD)((PCHAR)AttrRecord + AttrRecord->Length);
 168     }
 169
 170     DPRINT("Ended\n");
 171     return NULL;
 172 }
 173
 174
 175 NTSTATUS
 176 FindAttribute(PDEVICE_EXTENSION Vcb,
 177               PFILE_RECORD_HEADER MftRecord,
 178               ULONG Type,
 179               PUNICODE_STRING Name,
 180               PNTFS_ATTR_CONTEXT * AttrCtx)
 181 {
 182     PNTFS_ATTR_RECORD AttrRecord;
 183     PNTFS_ATTR_RECORD AttrRecordEnd;
 184
 185     DPRINT("NtfsFindAttribute(%p, %p, %u, %s)\n", Vcb, MftRecord, Type, Name);
 186
 187     AttrRecord = (PNTFS_ATTR_RECORD)((PCHAR)MftRecord + MftRecord->AttributeOffset);
 188     AttrRecordEnd = (PNTFS_ATTR_RECORD)((PCHAR)MftRecord + Vcb->NtfsInfo.BytesPerFileRecord);
 189
 190     *AttrCtx = FindAttributeHelper(Vcb, AttrRecord, AttrRecordEnd, Type, Name->Buffer, Name->Length);
 191     if (*AttrCtx == NULL)
 192     {
 193         return STATUS_OBJECT_NAME_NOT_FOUND;
 194     }
 195
 196     return STATUS_SUCCESS;
 197 }
 198
 199
 200 ULONG
 201 AttributeAllocatedLength(PNTFS_ATTR_RECORD AttrRecord)
 202 {
 203     if (AttrRecord->IsNonResident)
 204         return AttrRecord->NonResident.AllocatedSize;
 205     else
 206         return AttrRecord->Resident.ValueLength;
 207 }
 208
 209
 210 ULONGLONG
 211 AttributeDataLength(PNTFS_ATTR_RECORD AttrRecord)
 212 {
 213     if (AttrRecord->IsNonResident)
 214         return AttrRecord->NonResident.DataSize;
 215     else
 216         return AttrRecord->Resident.ValueLength;
 217 }
 218
 219
 220 ULONG
 221 ReadAttribute(PDEVICE_EXTENSION Vcb,
 222               PNTFS_ATTR_CONTEXT Context,
 223               ULONGLONG Offset,
 224               PCHAR Buffer,
 225               ULONG Length)
 226 {
 227     ULONGLONG LastLCN;
 228     PUCHAR DataRun;
 229     LONGLONG DataRunOffset;
 230     ULONGLONG DataRunLength;
 231     LONGLONG DataRunStartLCN;
 232     ULONGLONG CurrentOffset;
 233     ULONG ReadLength;
 234     ULONG AlreadyRead;
 235     NTSTATUS Status;
 236
 237     if (!Context->Record.IsNonResident)
 238     {
 239         if (Offset > Context->Record.Resident.ValueLength)
 240             return 0;
 241         if (Offset + Length > Context->Record.Resident.ValueLength)
 242             Length = (ULONG)(Context->Record.Resident.ValueLength - Offset);
 243         RtlCopyMemory(Buffer, (PCHAR)&Context->Record + Context->Record.Resident.ValueOffset + Offset, Length);
 244         return Length;
 245     }
 246
 247     /*
 248      * Non-resident attribute
 249      */
 250
 251     /*
 252      * I. Find the corresponding start data run.
 253      */
 254
 255     AlreadyRead = 0;
 256
 257     // FIXME: Cache seems to be non-working. Disable it for now
 258     //if(Context->CacheRunOffset <= Offset && Offset < Context->CacheRunOffset + Context->CacheRunLength * Volume->ClusterSize)
 259     if (0)
 260     {
 261         DataRun = Context->CacheRun;
 262         LastLCN = Context->CacheRunLastLCN;
 263         DataRunStartLCN = Context->CacheRunStartLCN;
 264         DataRunLength = Context->CacheRunLength;
 265         CurrentOffset = Context->CacheRunCurrentOffset;
 266     }
 267     else
 268     {
 269         LastLCN = 0;
 270         DataRun = (PUCHAR)&Context->Record + Context->Record.NonResident.MappingPairsOffset;
 271         CurrentOffset = 0;
 272
 273         while (1)
 274         {
 275             DataRun = DecodeRun(DataRun, &DataRunOffset, &DataRunLength);
 276             if (DataRunOffset != -1)
 277             {
 278                 /* Normal data run. */
 279                 DataRunStartLCN = LastLCN + DataRunOffset;
 280                 LastLCN = DataRunStartLCN;
 281             }
 282             else
 283             {
 284                 /* Sparse data run. */
 285                 DataRunStartLCN = -1;
 286             }
 287
 288             if (Offset >= CurrentOffset &&
 289                 Offset < CurrentOffset + (DataRunLength * Vcb->NtfsInfo.BytesPerCluster))
 290             {
 291                 break;
 292             }
 293
 294             if (*DataRun == 0)
 295             {
 296                 return AlreadyRead;
 297             }
 298
 299             CurrentOffset += DataRunLength * Vcb->NtfsInfo.BytesPerCluster;
 300         }
 301     }
 302
 303     /*
 304      * II. Go through the run list and read the data
 305      */
 306
 307     ReadLength = (ULONG)min(DataRunLength * Vcb->NtfsInfo.BytesPerCluster - (Offset - CurrentOffset), Length);
 308     if (DataRunStartLCN == -1)
 309         RtlZeroMemory(Buffer, ReadLength);
 310     Status = NtfsReadDisk(Vcb->StorageDevice,
 311                           DataRunStartLCN * Vcb->NtfsInfo.BytesPerCluster + Offset - CurrentOffset,
 312                           ReadLength,
 313                           (PVOID)Buffer,
 314                           FALSE);
 315     if (NT_SUCCESS(Status))
 316     {
 317         Length -= ReadLength;
 318         Buffer += ReadLength;
 319         AlreadyRead += ReadLength;
 320
 321         if (ReadLength == DataRunLength * Vcb->NtfsInfo.BytesPerCluster - (Offset - CurrentOffset))
 322         {
 323             CurrentOffset += DataRunLength * Vcb->NtfsInfo.BytesPerCluster;
 324             DataRun = DecodeRun(DataRun, &DataRunOffset, &DataRunLength);
 325             if (DataRunLength != (ULONGLONG)-1)
 326             {
 327                 DataRunStartLCN = LastLCN + DataRunOffset;
 328                 LastLCN = DataRunStartLCN;
 329             }
 330             else
 331                 DataRunStartLCN = -1;
 332
 333             if (*DataRun == 0)
 334                 return AlreadyRead;
 335         }
 336
 337         while (Length > 0)
 338         {
 339             ReadLength = (ULONG)min(DataRunLength * Vcb->NtfsInfo.BytesPerCluster, Length);
 340             if (DataRunStartLCN == -1)
 341                 RtlZeroMemory(Buffer, ReadLength);
 342             else
 343             {
 344                 Status = NtfsReadDisk(Vcb->StorageDevice,
 345                                       DataRunStartLCN * Vcb->NtfsInfo.BytesPerCluster,
 346                                       ReadLength,
 347                                       (PVOID)Buffer,
 348                                       FALSE);
 349                 if (!NT_SUCCESS(Status))
 350                     break;
 351             }
 352
 353             Length -= ReadLength;
 354             Buffer += ReadLength;
 355             AlreadyRead += ReadLength;
 356
 357             /* We finished this request, but there still data in this data run. */
 358             if (Length == 0 && ReadLength != DataRunLength * Vcb->NtfsInfo.BytesPerCluster)
 359                 break;
 360
 361             /*
 362              * Go to next run in the list.
 363              */
 364
 365             if (*DataRun == 0)
 366                 break;
 367             CurrentOffset += DataRunLength * Vcb->NtfsInfo.BytesPerCluster;
 368             DataRun = DecodeRun(DataRun, &DataRunOffset, &DataRunLength);
 369             if (DataRunOffset != -1)
 370             {
 371                 /* Normal data run. */
 372                 DataRunStartLCN = LastLCN + DataRunOffset;
 373                 LastLCN = DataRunStartLCN;
 374             }
 375             else
 376             {
 377                 /* Sparse data run. */
 378                 DataRunStartLCN = -1;
 379             }
 380         } /* while */
 381
 382     } /* if Disk */
 383
 384     Context->CacheRun = DataRun;
 385     Context->CacheRunOffset = Offset + AlreadyRead;
 386     Context->CacheRunStartLCN = DataRunStartLCN;
 387     Context->CacheRunLength = DataRunLength;
 388     Context->CacheRunLastLCN = LastLCN;
 389     Context->CacheRunCurrentOffset = CurrentOffset;
 390
 391     return AlreadyRead;
 392 }
 393
 394
 395 NTSTATUS
 396 ReadFileRecord(PDEVICE_EXTENSION Vcb,
 397                ULONGLONG index,
 398                PFILE_RECORD_HEADER file)
 399 {
 400     ULONGLONG BytesRead;
 401
 402     BytesRead = ReadAttribute(Vcb, Vcb->MFTContext, index * Vcb->NtfsInfo.BytesPerFileRecord, (PCHAR)file, Vcb->NtfsInfo.BytesPerFileRecord);
 403     if (BytesRead != Vcb->NtfsInfo.BytesPerFileRecord)
 404     {
 405         DPRINT1("ReadFileRecord failed: %u read, %u expected\n", BytesRead, Vcb->NtfsInfo.BytesPerFileRecord);
 406         return STATUS_PARTIAL_COPY;
 407     }
 408
 409     /* Apply update sequence array fixups. */
 410     return FixupUpdateSequenceArray(Vcb, &file->Ntfs);
 411 }
 412
 413
 414 NTSTATUS
 415 FixupUpdateSequenceArray(PDEVICE_EXTENSION Vcb,
 416                          PNTFS_RECORD_HEADER Record)
 417 {
 418     USHORT *USA;
 419     USHORT USANumber;
 420     USHORT USACount;
 421     USHORT *Block;
 422
 423     USA = (USHORT*)((PCHAR)Record + Record->UsaOffset);
 424     USANumber = *(USA++);
 425     USACount = Record->UsaCount - 1; /* Exclude the USA Number. */
 426     Block = (USHORT*)((PCHAR)Record + Vcb->NtfsInfo.BytesPerSector - 2);
 427
 428     while (USACount)
 429     {
 430         if (*Block != USANumber)
 431         {
 432             DPRINT1("Mismatch with USA: %u read, %u expected\n" , *Block, USANumber);
 433             return STATUS_UNSUCCESSFUL;
 434         }
 435         *Block = *(USA++);
 436         Block = (USHORT*)((PCHAR)Block + Vcb->NtfsInfo.BytesPerSector);
 437         USACount--;
 438     }
 439
 440     return STATUS_SUCCESS;
 441 }
 442
 443
 444 NTSTATUS
 445 ReadLCN(PDEVICE_EXTENSION Vcb,
 446         ULONGLONG lcn,
 447         ULONG count,
 448         PVOID buffer)
 449 {
 450     LARGE_INTEGER DiskSector;
 451
 452     DiskSector.QuadPart = lcn;
 453
 454     return NtfsReadSectors(Vcb->StorageDevice,
 455                            DiskSector.u.LowPart * Vcb->NtfsInfo.SectorsPerCluster,
 456                            count * Vcb->NtfsInfo.SectorsPerCluster,
 457                            Vcb->NtfsInfo.BytesPerSector,
 458                            buffer,
 459                            FALSE);
 460 }
 461
 462
 463 BOOLEAN
 464 CompareFileName(PUNICODE_STRING FileName,
 465                 PINDEX_ENTRY_ATTRIBUTE IndexEntry)
 466 {
 467     UNICODE_STRING EntryName;
 468
 469     EntryName.Buffer = IndexEntry->FileName.Name;
 470     EntryName.Length =
 471     EntryName.MaximumLength = IndexEntry->FileName.NameLength;
 472
 473     return (RtlCompareUnicodeString(FileName, &EntryName, !!(IndexEntry->FileName.NameType != NTFS_FILE_NAME_POSIX)) == TRUE);
 474 }
 475
 476
 477 NTSTATUS
 478 NtfsFindMftRecord(PDEVICE_EXTENSION Vcb, ULONGLONG MFTIndex, PUNICODE_STRING FileName, ULONGLONG *OutMFTIndex)
 479 {
 480     PFILE_RECORD_HEADER MftRecord;
 481     //ULONG Magic;
 482     PNTFS_ATTR_CONTEXT IndexRootCtx;
 483     PNTFS_ATTR_CONTEXT IndexBitmapCtx;
 484     PNTFS_ATTR_CONTEXT IndexAllocationCtx;
 485     PINDEX_ROOT_ATTRIBUTE IndexRoot;
 486     ULONGLONG BitmapDataSize;
 487     ULONGLONG IndexAllocationSize;
 488     PCHAR BitmapData;
 489     PCHAR IndexRecord;
 490     PINDEX_ENTRY_ATTRIBUTE IndexEntry, IndexEntryEnd;
 491     ULONG RecordOffset;
 492     ULONG IndexBlockSize;
 493     NTSTATUS Status;
 494
 495     MftRecord = ExAllocatePoolWithTag(NonPagedPool,
 496                                       Vcb->NtfsInfo.BytesPerFileRecord,
 497                                       TAG_NTFS);
 498     if (MftRecord == NULL)
 499     {
 500         return STATUS_INSUFFICIENT_RESOURCES;
 501     }
 502
 503     if (ReadFileRecord(Vcb, MFTIndex, MftRecord))
 504     {
 505         //Magic = MftRecord->Magic;
 506
 507         Status = FindAttribute(Vcb, MftRecord, AttributeIndexRoot, &IndexOfFileNames, &IndexRootCtx);
 508         if (!NT_SUCCESS(Status))
 509         {
 510             ExFreePoolWithTag(MftRecord, TAG_NTFS);
 511             return Status;
 512         }
 513
 514         IndexRecord = ExAllocatePoolWithTag(NonPagedPool, Vcb->NtfsInfo.BytesPerIndexRecord, TAG_NTFS);
 515         if (IndexRecord == NULL)
 516         {
 517             ExFreePoolWithTag(MftRecord, TAG_NTFS);
 518             return STATUS_INSUFFICIENT_RESOURCES;
 519         }
 520
 521         ReadAttribute(Vcb, IndexRootCtx, 0, IndexRecord, Vcb->NtfsInfo.BytesPerIndexRecord);
 522         IndexRoot = (PINDEX_ROOT_ATTRIBUTE)IndexRecord;
 523         IndexEntry = (PINDEX_ENTRY_ATTRIBUTE)((PCHAR)&IndexRoot->Header + IndexRoot->Header.FirstEntryOffset);
 524         /* Index root is always resident. */
 525         IndexEntryEnd = (PINDEX_ENTRY_ATTRIBUTE)(IndexRecord + IndexRootCtx->Record.Resident.ValueLength);
 526         ReleaseAttributeContext(IndexRootCtx);
 527
 528         DPRINT("IndexRecordSize: %x IndexBlockSize: %x\n", Vcb->NtfsInfo.BytesPerIndexRecord, IndexRoot->SizeOfEntry);
 529
 530         while (IndexEntry < IndexEntryEnd &&
 531                !(IndexEntry->Flags & NTFS_INDEX_ENTRY_END))
 532         {
 533             if (CompareFileName(FileName, IndexEntry))
 534             {
 535                 *OutMFTIndex = IndexEntry->Data.Directory.IndexedFile;
 536                 ExFreePoolWithTag(IndexRecord, TAG_NTFS);
 537                 ExFreePoolWithTag(MftRecord, TAG_NTFS);
 538                 return STATUS_SUCCESS;
 539             }
 540         IndexEntry = (PINDEX_ENTRY_ATTRIBUTE)((PCHAR)IndexEntry + IndexEntry->Length);
 541         }
 542
 543         if (IndexRoot->Header.Flags & INDEX_ROOT_LARGE)
 544         {
 545             DPRINT("Large Index!\n");
 546
 547             IndexBlockSize = IndexRoot->SizeOfEntry;
 548
 549             Status = FindAttribute(Vcb, MftRecord, AttributeBitmap, &IndexOfFileNames, &IndexBitmapCtx);
 550             if (!NT_SUCCESS(Status))
 551             {
 552                 DPRINT("Corrupted filesystem!\n");
 553                 ExFreePoolWithTag(MftRecord, TAG_NTFS);
 554                 return Status;
 555             }
 556             BitmapDataSize = AttributeDataLength(&IndexBitmapCtx->Record);
 557             DPRINT("BitmapDataSize: %x\n", (ULONG)BitmapDataSize);
 558             if(BitmapDataSize <= 0xFFFFFFFF)
 559                 BitmapData = ExAllocatePoolWithTag(NonPagedPool, (ULONG)BitmapDataSize, TAG_NTFS);
 560             else
 561                 BitmapData = NULL;
 562
 563             if (BitmapData == NULL)
 564             {
 565                 ExFreePoolWithTag(IndexRecord, TAG_NTFS);
 566                 ExFreePoolWithTag(MftRecord, TAG_NTFS);
 567                 return STATUS_INSUFFICIENT_RESOURCES;
 568             }
 569             ReadAttribute(Vcb, IndexBitmapCtx, 0, BitmapData, (ULONG)BitmapDataSize);
 570             ReleaseAttributeContext(IndexBitmapCtx);
 571
 572             Status = FindAttribute(Vcb, MftRecord, AttributeIndexAllocation, &IndexOfFileNames, &IndexAllocationCtx);
 573             if (!NT_SUCCESS(Status))
 574             {
 575                 DPRINT("Corrupted filesystem!\n");
 576                 ExFreePoolWithTag(BitmapData, TAG_NTFS);
 577                 ExFreePoolWithTag(IndexRecord, TAG_NTFS);
 578                 ExFreePoolWithTag(MftRecord, TAG_NTFS);
 579                 return Status;
 580             }
 581             IndexAllocationSize = AttributeDataLength(&IndexAllocationCtx->Record);
 582
 583             RecordOffset = 0;
 584
 585             for (;;)
 586             {
 587                 DPRINT("RecordOffset: %x IndexAllocationSize: %x\n", RecordOffset, IndexAllocationSize);
 588                 for (; RecordOffset < IndexAllocationSize;)
 589                 {
 590                     UCHAR Bit = 1 << ((RecordOffset / IndexBlockSize) & 7);
 591                     ULONG Byte = (RecordOffset / IndexBlockSize) >> 3;
 592                     if ((BitmapData[Byte] & Bit))
 593                         break;
 594                     RecordOffset += IndexBlockSize;
 595                 }
 596
 597                 if (RecordOffset >= IndexAllocationSize)
 598                 {
 599                     break;
 600                 }
 601
 602                 ReadAttribute(Vcb, IndexAllocationCtx, RecordOffset, IndexRecord, IndexBlockSize);
 603
 604                 if (!FixupUpdateSequenceArray(Vcb, &((PFILE_RECORD_HEADER)IndexRecord)->Ntfs))
 605                 {
 606                     break;
 607                 }
 608
 609                 /* FIXME */
 610                 IndexEntry = (PINDEX_ENTRY_ATTRIBUTE)(IndexRecord + 0x18 + *(USHORT *)(IndexRecord + 0x18));
 611                 IndexEntryEnd = (PINDEX_ENTRY_ATTRIBUTE)(IndexRecord + IndexBlockSize);
 612
 613                 while (IndexEntry < IndexEntryEnd &&
 614                        !(IndexEntry->Flags & NTFS_INDEX_ENTRY_END))
 615                 {
 616                     if (CompareFileName(FileName, IndexEntry))
 617                     {
 618                         DPRINT("File found\n");
 619                         *OutMFTIndex = IndexEntry->Data.Directory.IndexedFile;
 620                         ExFreePoolWithTag(BitmapData, TAG_NTFS);
 621                         ExFreePoolWithTag(IndexRecord, TAG_NTFS);
 622                         ExFreePoolWithTag(MftRecord, TAG_NTFS);
 623                         ReleaseAttributeContext(IndexAllocationCtx);
 624                         return STATUS_SUCCESS;
 625                     }
 626                     IndexEntry = (PINDEX_ENTRY_ATTRIBUTE)((PCHAR)IndexEntry + IndexEntry->Length);
 627                 }
 628
 629                 RecordOffset += IndexBlockSize;
 630             }
 631
 632             ReleaseAttributeContext(IndexAllocationCtx);
 633             ExFreePoolWithTag(BitmapData, TAG_NTFS);
 634         }
 635
 636         ExFreePoolWithTag(IndexRecord, TAG_NTFS);
 637     }
 638     else
 639     {
 640         DPRINT("Can't read MFT record\n");
 641     }
 642     ExFreePoolWithTag(MftRecord, TAG_NTFS);
 643
 644     return STATUS_OBJECT_PATH_NOT_FOUND;
 645 }
 646
 647 NTSTATUS
 648 NtfsLookupFileAt(PDEVICE_EXTENSION Vcb,
 649                  PUNICODE_STRING PathName,
 650                  PFILE_RECORD_HEADER *FileRecord,
 651                  PNTFS_ATTR_CONTEXT *DataContext,
 652                  ULONGLONG CurrentMFTIndex)
 653 {
 654     UNICODE_STRING Current, Remaining;
 655     NTSTATUS Status;
 656
 657     DPRINT1("NtfsLookupFileAt(%p, %wZ, %p, %p, %I64x)\n", Vcb, PathName, FileRecord, DataContext, CurrentMFTIndex);
 658
 659     FsRtlDissectName(*PathName, &Current, &Remaining);
 660
 661     while (Current.Length != 0)
 662     {
 663         DPRINT1("Lookup: %wZ\n", &Current);
 664
 665         Status = NtfsFindMftRecord(Vcb, CurrentMFTIndex, &Current, &CurrentMFTIndex);
 666         if (!NT_SUCCESS(Status))
 667         {
 668             return Status;
 669         }
 670
 671         FsRtlDissectName(*PathName, &Current, &Remaining);
 672     }
 673
 674     *FileRecord = ExAllocatePoolWithTag(NonPagedPool, Vcb->NtfsInfo.BytesPerFileRecord, TAG_NTFS);
 675     if (*FileRecord == NULL)
 676     {
 677         DPRINT("NtfsLookupFile: Can't allocate MFT record\n");
 678         return STATUS_INSUFFICIENT_RESOURCES;
 679     }
 680
 681     Status = ReadFileRecord(Vcb, CurrentMFTIndex, *FileRecord);
 682     if (!NT_SUCCESS(Status))
 683     {
 684         DPRINT("NtfsLookupFile: Can't read MFT record\n");
 685         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 686         return Status;
 687     }
 688
 689     Status = FindAttribute(Vcb, *FileRecord, AttributeData, PathName, DataContext);
 690     if (!NT_SUCCESS(Status))
 691     {
 692         DPRINT("NtfsLookupFile: Can't find data attribute\n");
 693         ExFreePoolWithTag(FileRecord, TAG_NTFS);
 694         return Status;
 695     }
 696
 697     return STATUS_SUCCESS;
 698 }
 699
 700 NTSTATUS
 701 NtfsLookupFile(PDEVICE_EXTENSION Vcb,
 702                PUNICODE_STRING PathName,
 703                PFILE_RECORD_HEADER *FileRecord,
 704                PNTFS_ATTR_CONTEXT *DataContext)
 705 {
 706     return NtfsLookupFileAt(Vcb, PathName, FileRecord, DataContext, NTFS_FILE_ROOT);
 707 }
 708 /* EOF */