From c606f0866c3a2a5db3ef9bc41738ef33eb9612a9 Mon Sep 17 00:00:00 2001 From: Mounir IDRASSI Date: Sat, 22 Jun 2013 16:16:13 +0200 Subject: Add original TrueCrypt 7.1a sources --- src/Boot/Windows/BootDiskIo.cpp | 487 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 487 insertions(+) create mode 100644 src/Boot/Windows/BootDiskIo.cpp (limited to 'src/Boot/Windows/BootDiskIo.cpp') diff --git a/src/Boot/Windows/BootDiskIo.cpp b/src/Boot/Windows/BootDiskIo.cpp new file mode 100644 index 00000000..84e888e0 --- /dev/null +++ b/src/Boot/Windows/BootDiskIo.cpp @@ -0,0 +1,487 @@ +/* + Copyright (c) 2008-2011 TrueCrypt Developers Association. All rights reserved. + + Governed by the TrueCrypt License 3.0 the full text of which is contained in + the file License.txt included in TrueCrypt binary and source code distribution + packages. +*/ + +#include "Bios.h" +#include "BootConsoleIo.h" +#include "BootConfig.h" +#include "BootDebug.h" +#include "BootDefs.h" +#include "BootDiskIo.h" +#include "BootStrings.h" + + +byte SectorBuffer[TC_LB_SIZE]; + +#ifdef TC_BOOT_DEBUG_ENABLED +static bool SectorBufferInUse = false; + +void AcquireSectorBuffer () +{ + if (SectorBufferInUse) + TC_THROW_FATAL_EXCEPTION; + + SectorBufferInUse = true; +} + + +void ReleaseSectorBuffer () +{ + SectorBufferInUse = false; +} + +#endif + + +bool IsLbaSupported (byte drive) +{ + static byte CachedDrive = TC_INVALID_BIOS_DRIVE; + static bool CachedStatus; + uint16 result = 0; + + if (CachedDrive == drive) + goto ret; + + __asm + { + mov bx, 0x55aa + mov dl, drive + mov ah, 0x41 + int 0x13 + jc err + mov result, bx + err: + } + + CachedDrive = drive; + CachedStatus = (result == 0xaa55); +ret: + return CachedStatus; +} + + +void PrintDiskError (BiosResult error, bool write, byte drive, const uint64 *sector, const ChsAddress *chs) +{ + PrintEndl(); + Print (write ? "Write" : "Read"); Print (" error:"); + Print (error); + Print (" Drive:"); + Print (drive ^ 0x80); + + if (sector) + { + Print (" Sector:"); + Print (*sector); + } + + if (chs) + { + Print (" CHS:"); + Print (*chs); + } + + PrintEndl(); + Beep(); +} + + +void Print (const ChsAddress &chs) +{ + Print (chs.Cylinder); + PrintChar ('/'); + Print (chs.Head); + PrintChar ('/'); + Print (chs.Sector); +} + + +void PrintSectorCountInMB (const uint64 §orCount) +{ + Print (sectorCount >> (TC_LB_SIZE_BIT_SHIFT_DIVISOR + 2)); Print (" MB "); +} + + +BiosResult ReadWriteSectors (bool write, uint16 bufferSegment, uint16 bufferOffset, byte drive, const ChsAddress &chs, byte sectorCount, bool silent) +{ + CheckStack(); + + byte cylinderLow = (byte) chs.Cylinder; + byte sector = chs.Sector; + sector |= byte (chs.Cylinder >> 2) & 0xc0; + byte function = write ? 0x03 : 0x02; + + BiosResult result; + byte tryCount = TC_MAX_BIOS_DISK_IO_RETRIES; + + do + { + result = BiosResultSuccess; + + __asm + { + push es + mov ax, bufferSegment + mov es, ax + mov bx, bufferOffset + mov dl, drive + mov ch, cylinderLow + mov si, chs + mov dh, [si].Head + mov cl, sector + mov al, sectorCount + mov ah, function + int 0x13 + jnc ok // If CF=0, ignore AH to prevent issues caused by potential bugs in BIOSes + mov result, ah + ok: + pop es + } + + if (result == BiosResultEccCorrected) + result = BiosResultSuccess; + + // Some BIOSes report I/O errors prematurely in some cases + } while (result != BiosResultSuccess && --tryCount != 0); + + if (!silent && result != BiosResultSuccess) + PrintDiskError (result, write, drive, nullptr, &chs); + + return result; +} + + +BiosResult ReadWriteSectors (bool write, byte *buffer, byte drive, const ChsAddress &chs, byte sectorCount, bool silent) +{ + uint16 codeSeg; + __asm mov codeSeg, cs + return ReadWriteSectors (write, codeSeg, (uint16) buffer, drive, chs, sectorCount, silent); +} + + +BiosResult ReadSectors (byte *buffer, byte drive, const ChsAddress &chs, byte sectorCount, bool silent) +{ + return ReadWriteSectors (false, buffer, drive, chs, sectorCount, silent); +} + + +BiosResult WriteSectors (byte *buffer, byte drive, const ChsAddress &chs, byte sectorCount, bool silent) +{ + return ReadWriteSectors (true, buffer, drive, chs, sectorCount, silent); +} + + +static BiosResult ReadWriteSectors (bool write, BiosLbaPacket &dapPacket, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + CheckStack(); + + if (!IsLbaSupported (drive)) + { + DriveGeometry geometry; + + BiosResult result = GetDriveGeometry (drive, geometry, silent); + if (result != BiosResultSuccess) + return result; + + ChsAddress chs; + LbaToChs (geometry, sector, chs); + return ReadWriteSectors (write, (uint16) (dapPacket.Buffer >> 16), (uint16) dapPacket.Buffer, drive, chs, sectorCount, silent); + } + + dapPacket.Size = sizeof (dapPacket); + dapPacket.Reserved = 0; + dapPacket.SectorCount = sectorCount; + dapPacket.Sector = sector; + + byte function = write ? 0x43 : 0x42; + + BiosResult result; + byte tryCount = TC_MAX_BIOS_DISK_IO_RETRIES; + + do + { + result = BiosResultSuccess; + + __asm + { + mov bx, 0x55aa + mov dl, drive + mov si, [dapPacket] + mov ah, function + xor al, al + int 0x13 + jnc ok // If CF=0, ignore AH to prevent issues caused by potential bugs in BIOSes + mov result, ah + ok: + } + + if (result == BiosResultEccCorrected) + result = BiosResultSuccess; + + // Some BIOSes report I/O errors prematurely in some cases + } while (result != BiosResultSuccess && --tryCount != 0); + + if (!silent && result != BiosResultSuccess) + PrintDiskError (result, write, drive, §or); + + return result; +} + + +static BiosResult ReadWriteSectors (bool write, byte *buffer, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + BiosLbaPacket dapPacket; + dapPacket.Buffer = (uint32) buffer; + return ReadWriteSectors (write, dapPacket, drive, sector, sectorCount, silent); +} + + +BiosResult ReadWriteSectors (bool write, uint16 bufferSegment, uint16 bufferOffset, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + BiosLbaPacket dapPacket; + dapPacket.Buffer = ((uint32) bufferSegment << 16) | bufferOffset; + return ReadWriteSectors (write, dapPacket, drive, sector, sectorCount, silent); +} + +BiosResult ReadSectors (uint16 bufferSegment, uint16 bufferOffset, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + return ReadWriteSectors (false, bufferSegment, bufferOffset, drive, sector, sectorCount, silent); +} + + +BiosResult ReadSectors (byte *buffer, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + BiosResult result; + uint16 codeSeg; + __asm mov codeSeg, cs + + result = ReadSectors (BootStarted ? codeSeg : TC_BOOT_LOADER_ALT_SEGMENT, (uint16) buffer, drive, sector, sectorCount, silent); + + // Alternative segment is used to prevent memory corruption caused by buggy BIOSes + if (!BootStarted) + CopyMemory (TC_BOOT_LOADER_ALT_SEGMENT, (uint16) buffer, buffer, sectorCount * TC_LB_SIZE); + + return result; +} + + +BiosResult WriteSectors (byte *buffer, byte drive, const uint64 §or, uint16 sectorCount, bool silent) +{ + return ReadWriteSectors (true, buffer, drive, sector, sectorCount, silent); +} + + +BiosResult GetDriveGeometry (byte drive, DriveGeometry &geometry, bool silent) +{ + CheckStack(); + + byte maxCylinderLow, maxHead, maxSector; + BiosResult result; + __asm + { + push es + mov dl, drive + mov ah, 0x08 + int 0x13 + + mov result, ah + mov maxCylinderLow, ch + mov maxSector, cl + mov maxHead, dh + pop es + } + + if (result == BiosResultSuccess) + { + geometry.Cylinders = (maxCylinderLow | (uint16 (maxSector & 0xc0) << 2)) + 1; + geometry.Heads = maxHead + 1; + geometry.Sectors = maxSector & ~0xc0; + } + else if (!silent) + { + Print ("Drive "); + Print (drive ^ 0x80); + Print (" not found: "); + PrintErrorNoEndl (""); + Print (result); + PrintEndl(); + } + + return result; +} + + +void ChsToLba (const DriveGeometry &geometry, const ChsAddress &chs, uint64 &lba) +{ + lba.HighPart = 0; + lba.LowPart = (uint32 (chs.Cylinder) * geometry.Heads + chs.Head) * geometry.Sectors + chs.Sector - 1; +} + + +void LbaToChs (const DriveGeometry &geometry, const uint64 &lba, ChsAddress &chs) +{ + chs.Sector = (byte) ((lba.LowPart % geometry.Sectors) + 1); + uint32 ch = lba.LowPart / geometry.Sectors; + chs.Head = (byte) (ch % geometry.Heads); + chs.Cylinder = (uint16) (ch / geometry.Heads); +} + + +void PartitionEntryMBRToPartition (const PartitionEntryMBR &partEntry, Partition &partition) +{ + partition.Active = partEntry.BootIndicator == 0x80; + partition.EndSector.HighPart = 0; + partition.EndSector.LowPart = partEntry.StartLBA + partEntry.SectorCountLBA - 1; + partition.SectorCount.HighPart = 0; + partition.SectorCount.LowPart = partEntry.SectorCountLBA; + partition.StartSector.HighPart = 0; + partition.StartSector.LowPart = partEntry.StartLBA; + partition.Type = partEntry.Type; +} + + +BiosResult ReadWriteMBR (bool write, byte drive, bool silent) +{ + uint64 mbrSector; + mbrSector.HighPart = 0; + mbrSector.LowPart = 0; + + if (write) + return WriteSectors (SectorBuffer, drive, mbrSector, 1, silent); + + return ReadSectors (SectorBuffer, drive, mbrSector, 1, silent); // Uses alternative segment +} + + +BiosResult GetDrivePartitions (byte drive, Partition *partitionArray, size_t partitionArrayCapacity, size_t &partitionCount, bool activeOnly, Partition *findPartitionFollowingThis, bool silent) +{ + Partition *followingPartition; + Partition tmpPartition; + + if (findPartitionFollowingThis) + { + assert (partitionArrayCapacity == 1); + partitionArrayCapacity = 0xff; + followingPartition = partitionArray; + partitionArray = &tmpPartition; + + followingPartition->Drive = TC_INVALID_BIOS_DRIVE; + followingPartition->StartSector.LowPart = 0xFFFFffffUL; + } + + AcquireSectorBuffer(); + BiosResult result = ReadWriteMBR (false, drive, silent); + ReleaseSectorBuffer(); + + partitionCount = 0; + + MBR *mbr = (MBR *) SectorBuffer; + if (result != BiosResultSuccess || mbr->Signature != 0xaa55) + return result; + + PartitionEntryMBR mbrPartitions[4]; + memcpy (mbrPartitions, mbr->Partitions, sizeof (mbrPartitions)); + size_t partitionArrayPos = 0, partitionNumber; + + for (partitionNumber = 0; + partitionNumber < array_capacity (mbrPartitions) && partitionArrayPos < partitionArrayCapacity; + ++partitionNumber) + { + const PartitionEntryMBR &partEntry = mbrPartitions[partitionNumber]; + + if (partEntry.SectorCountLBA > 0) + { + Partition &partition = partitionArray[partitionArrayPos]; + PartitionEntryMBRToPartition (partEntry, partition); + + if (activeOnly && !partition.Active) + continue; + + partition.Drive = drive; + partition.Number = partitionArrayPos; + + if (partEntry.Type == 0x5 || partEntry.Type == 0xf) // Extended partition + { + if (IsLbaSupported (drive)) + { + // Find all extended partitions + uint64 firstExtStartLBA = partition.StartSector; + uint64 extStartLBA = partition.StartSector; + MBR *extMbr = (MBR *) SectorBuffer; + + while (partitionArrayPos < partitionArrayCapacity && + (result = ReadSectors ((byte *) extMbr, drive, extStartLBA, 1, silent)) == BiosResultSuccess + && extMbr->Signature == 0xaa55) + { + if (extMbr->Partitions[0].SectorCountLBA > 0) + { + Partition &logPart = partitionArray[partitionArrayPos]; + PartitionEntryMBRToPartition (extMbr->Partitions[0], logPart); + logPart.Drive = drive; + + logPart.Number = partitionArrayPos; + logPart.Primary = false; + + logPart.StartSector.LowPart += extStartLBA.LowPart; + logPart.EndSector.LowPart += extStartLBA.LowPart; + + if (findPartitionFollowingThis) + { + if (logPart.StartSector.LowPart > findPartitionFollowingThis->EndSector.LowPart + && logPart.StartSector.LowPart < followingPartition->StartSector.LowPart) + { + *followingPartition = logPart; + } + } + else + ++partitionArrayPos; + } + + // Secondary extended + if (extMbr->Partitions[1].Type != 0x5 && extMbr->Partitions[1].Type == 0xf + || extMbr->Partitions[1].SectorCountLBA == 0) + break; + + extStartLBA.LowPart = extMbr->Partitions[1].StartLBA + firstExtStartLBA.LowPart; + } + } + } + else + { + partition.Primary = true; + + if (findPartitionFollowingThis) + { + if (partition.StartSector.LowPart > findPartitionFollowingThis->EndSector.LowPart + && partition.StartSector.LowPart < followingPartition->StartSector.LowPart) + { + *followingPartition = partition; + } + } + else + ++partitionArrayPos; + } + } + } + + partitionCount = partitionArrayPos; + return result; +} + + +bool GetActivePartition (byte drive) +{ + size_t partCount; + + if (GetDrivePartitions (drive, &ActivePartition, 1, partCount, true) != BiosResultSuccess || partCount < 1) + { + ActivePartition.Drive = TC_INVALID_BIOS_DRIVE; + PrintError (TC_BOOT_STR_NO_BOOT_PARTITION); + return false; + } + + return true; +} -- cgit v1.2.3