reactos/sdk/lib/cmlib/hivewrt.c
Hermès Bélusca-Maïto feb67576dd
[NTOS:CM][CMLIB] In PE mode, allow registry hives (except system ones) to use read/write access.
+ Improve related comments.

Registry hives are opened in shared read access when NT is loaded in PE
mode (MININT) or from network (the hives residing on a network share).
This is true in particular for the main system hives (SYSTEM, SOFTWARE,
DEFAULT, ...).

However, in PE mode, we can allow other hives, e.g. those loaded by the
user (with NtLoadKey) to be loaded with full read/write access, since we
boot from a local computer.
2024-01-17 22:13:03 +01:00

682 lines
20 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
* PURPOSE: Configuration Manager Library - Registry Syncing & Hive/Log/Alternate Writing
* COPYRIGHT: Copyright 2001 - 2005 Eric Kohl
* Copyright 2005 Filip Navara <navaraf@reactos.org>
* Copyright 2021 Max Korostil
* Copyright 2022 George Bișoc <george.bisoc@reactos.org>
*/
#include "cmlib.h"
#define NDEBUG
#include <debug.h>
/* DECLARATIONS *************************************************************/
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
BOOLEAN
NTAPI
IoSetThreadHardErrorMode(
_In_ BOOLEAN HardErrorEnabled);
#endif
/* GLOBALS ******************************************************************/
/* PRIVATE FUNCTIONS ********************************************************/
/**
* @brief
* Validates the base block header of a primary
* hive for consistency.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor to look
* for the header block.
*/
static
VOID
HvpValidateBaseHeader(
_In_ PHHIVE RegistryHive)
{
PHBASE_BLOCK BaseBlock;
/*
* Cache the base block and validate it.
* Especially...
*
* 1. It must must have a valid signature.
* 2. It must have a valid format.
* 3. It must be of an adequate major version,
* not anything else.
*/
BaseBlock = RegistryHive->BaseBlock;
ASSERT(BaseBlock->Signature == HV_HBLOCK_SIGNATURE);
ASSERT(BaseBlock->Format == HBASE_FORMAT_MEMORY);
ASSERT(BaseBlock->Major == HSYS_MAJOR);
}
/**
* @unimplemented
* @brief
* Writes dirty data in a transacted way to a hive
* log file during hive syncing operation. Log
* files are used by the kernel/bootloader to
* perform recovery operations against a
* damaged primary hive.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where the log
* belongs to and of which we write data into the
* said log.
*
* @return
* Returns TRUE if log transaction writing has succeeded,
* FALSE otherwise.
*
* @remarks
* The function is not completely implemented, that is,
* it lacks the implementation for growing the log file size.
* See the FIXME comment below for further details.
*/
static
BOOLEAN
CMAPI
HvpWriteLog(
_In_ PHHIVE RegistryHive)
{
BOOLEAN Success;
ULONG FileOffset;
ULONG BlockIndex;
ULONG LastIndex;
PVOID Block;
UINT32 BitmapSize, BufferSize;
PUCHAR HeaderBuffer, Ptr;
/*
* The hive log we are going to write data into
* has to be writable and with a sane storage.
*/
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->BaseBlock->Length ==
RegistryHive->Storage[Stable].Length * HBLOCK_SIZE);
/* Validate the base header before we go further */
HvpValidateBaseHeader(RegistryHive);
/*
* The sequences can diverge during a forced system shutdown
* occurrence, such as during a power failure, a hardware
* failure or during a system crash, and when one of the
* sequences have been modified during writing into the log
* or hive. In such cases the hive needs a repair.
*/
if (RegistryHive->BaseBlock->Sequence1 !=
RegistryHive->BaseBlock->Sequence2)
{
DPRINT1("The sequences DO NOT MATCH (Sequence1 == 0x%x, Sequence2 == 0x%x)\n",
RegistryHive->BaseBlock->Sequence1, RegistryHive->BaseBlock->Sequence2);
return FALSE;
}
/*
* FIXME: We must set a new file size for this log
* here but ReactOS lacks the necessary code implementation
* that manages the growing and shrinking of a hive's log
* size. So for now don't set any new size for the log.
*/
/*
* Now calculate the bitmap and buffer sizes to hold up our
* contents in a buffer.
*/
BitmapSize = ROUND_UP(sizeof(ULONG) + RegistryHive->DirtyVector.SizeOfBitMap / 8, HSECTOR_SIZE);
BufferSize = HV_LOG_HEADER_SIZE + BitmapSize;
/* Now allocate the base header block buffer */
HeaderBuffer = RegistryHive->Allocate(BufferSize, TRUE, TAG_CM);
if (!HeaderBuffer)
{
DPRINT1("Couldn't allocate buffer for base header block\n");
return FALSE;
}
/* Great, now zero out the buffer */
RtlZeroMemory(HeaderBuffer, BufferSize);
/*
* Update the base block of this hive and
* increment the primary sequence number
* as we are at the half of the work.
*/
RegistryHive->BaseBlock->Type = HFILE_TYPE_LOG;
RegistryHive->BaseBlock->Sequence1++;
RegistryHive->BaseBlock->CheckSum = HvpHiveHeaderChecksum(RegistryHive->BaseBlock);
/* Copy the base block header */
RtlCopyMemory(HeaderBuffer, RegistryHive->BaseBlock, HV_LOG_HEADER_SIZE);
Ptr = HeaderBuffer + HV_LOG_HEADER_SIZE;
/* Copy the dirty vector */
*((PULONG)Ptr) = HV_LOG_DIRTY_SIGNATURE;
Ptr += sizeof(HV_LOG_DIRTY_SIGNATURE);
/*
* FIXME: In ReactOS a vector contains one bit per block
* whereas in Windows each bit within a vector is per
* sector. Furthermore, the dirty blocks within a respective
* hive has to be marked as such in an appropriate function
* for this purpose (probably HvMarkDirty or similar).
*
* For the moment being, mark the relevant dirty blocks
* here.
*/
BlockIndex = 0;
while (BlockIndex < RegistryHive->Storage[Stable].Length)
{
/* Check if the block is clean or we're past the last block */
LastIndex = BlockIndex;
BlockIndex = RtlFindSetBits(&RegistryHive->DirtyVector, 1, BlockIndex);
if (BlockIndex == ~HV_CLEAN_BLOCK || BlockIndex < LastIndex)
{
break;
}
/*
* Mark this block as dirty and go to the next one.
*
* FIXME: We should rather use RtlSetBits but that crashes
* the system with a bugckeck. So for now mark blocks manually
* by hand.
*/
Ptr[BlockIndex] = HV_LOG_DIRTY_BLOCK;
BlockIndex++;
}
/* Now write the hive header and block bitmap into the log */
FileOffset = 0;
Success = RegistryHive->FileWrite(RegistryHive, HFILE_TYPE_LOG,
&FileOffset, HeaderBuffer, BufferSize);
RegistryHive->Free(HeaderBuffer, 0);
if (!Success)
{
DPRINT1("Failed to write the hive header block to log (primary sequence)\n");
return FALSE;
}
/* Now write the actual dirty data to log */
FileOffset = BufferSize;
BlockIndex = 0;
while (BlockIndex < RegistryHive->Storage[Stable].Length)
{
/* Check if the block is clean or we're past the last block */
LastIndex = BlockIndex;
BlockIndex = RtlFindSetBits(&RegistryHive->DirtyVector, 1, BlockIndex);
if (BlockIndex == ~HV_CLEAN_BLOCK || BlockIndex < LastIndex)
{
break;
}
/* Get the block */
Block = (PVOID)RegistryHive->Storage[Stable].BlockList[BlockIndex].BlockAddress;
/* Write it to log */
Success = RegistryHive->FileWrite(RegistryHive, HFILE_TYPE_LOG,
&FileOffset, Block, HBLOCK_SIZE);
if (!Success)
{
DPRINT1("Failed to write dirty block to log (block 0x%p, block index 0x%x)\n", Block, BlockIndex);
return FALSE;
}
/* Grow up the file offset as we go to the next block */
BlockIndex++;
FileOffset += HBLOCK_SIZE;
}
/*
* We wrote the header and body of log with dirty,
* data do a flush immediately.
*/
Success = RegistryHive->FileFlush(RegistryHive, HFILE_TYPE_LOG, NULL, 0);
if (!Success)
{
DPRINT1("Failed to flush the log\n");
return FALSE;
}
/*
* OK, we're now at 80% of the work done.
* Increment the secondary sequence and flush
* the log again. We can have a fully successful
* transacted write of a log if the sequences
* are synced up properly.
*/
RegistryHive->BaseBlock->Sequence2++;
RegistryHive->BaseBlock->CheckSum = HvpHiveHeaderChecksum(RegistryHive->BaseBlock);
/* Write new stuff into log first */
FileOffset = 0;
Success = RegistryHive->FileWrite(RegistryHive, HFILE_TYPE_LOG,
&FileOffset, RegistryHive->BaseBlock,
HV_LOG_HEADER_SIZE);
if (!Success)
{
DPRINT1("Failed to write the log file (secondary sequence)\n");
return FALSE;
}
/* Flush it finally */
Success = RegistryHive->FileFlush(RegistryHive, HFILE_TYPE_LOG, NULL, 0);
if (!Success)
{
DPRINT1("Failed to flush the log\n");
return FALSE;
}
return TRUE;
}
/**
* @brief
* Writes data (dirty or non) to a primary hive during
* syncing operation. Hive writing is also performed
* during a flush occurrence on request by the system.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where the data is
* to be written to that hive.
*
* @param[in] OnlyDirty
* If set to TRUE, the function only looks for dirty
* data to be written to the primary hive, otherwise if
* it's set to FALSE then the function writes all the data.
*
* @param[in] FileType
* The file type of a registry hive. This can be HFILE_TYPE_PRIMARY
* or HFILE_TYPE_ALTERNATE.
*
* @return
* Returns TRUE if writing to hive has succeeded,
* FALSE otherwise.
*
* @remarks
* The on-disk header metadata of a hive is already written with type
* of HFILE_TYPE_PRIMARY, regardless of what file type the caller submits,
* as an alternate hive is basically a mirror of the primary hive.
*/
static
BOOLEAN
CMAPI
HvpWriteHive(
_In_ PHHIVE RegistryHive,
_In_ BOOLEAN OnlyDirty,
_In_ ULONG FileType)
{
BOOLEAN Success;
ULONG FileOffset;
ULONG BlockIndex;
ULONG LastIndex;
PVOID Block;
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->BaseBlock->Length ==
RegistryHive->Storage[Stable].Length * HBLOCK_SIZE);
ASSERT(RegistryHive->BaseBlock->RootCell != HCELL_NIL);
/* Validate the base header before we go further */
HvpValidateBaseHeader(RegistryHive);
/*
* The sequences can diverge during a forced system shutdown
* occurrence, such as during a power failure, a hardware
* failure or during a system crash, and when one of the
* sequences have been modified during writing into the log
* or hive. In such cases the hive needs a repair.
*/
if (RegistryHive->BaseBlock->Sequence1 !=
RegistryHive->BaseBlock->Sequence2)
{
DPRINT1("The sequences DO NOT MATCH (Sequence1 == 0x%x, Sequence2 == 0x%x)\n",
RegistryHive->BaseBlock->Sequence1, RegistryHive->BaseBlock->Sequence2);
return FALSE;
}
/*
* Update the primary sequence number and write
* the base block to hive.
*/
RegistryHive->BaseBlock->Type = HFILE_TYPE_PRIMARY;
RegistryHive->BaseBlock->Sequence1++;
RegistryHive->BaseBlock->CheckSum = HvpHiveHeaderChecksum(RegistryHive->BaseBlock);
/* Write hive block */
FileOffset = 0;
Success = RegistryHive->FileWrite(RegistryHive, FileType,
&FileOffset, RegistryHive->BaseBlock,
sizeof(HBASE_BLOCK));
if (!Success)
{
DPRINT1("Failed to write the base block header to primary hive (primary sequence)\n");
return FALSE;
}
/* Write the whole primary hive, block by block */
BlockIndex = 0;
while (BlockIndex < RegistryHive->Storage[Stable].Length)
{
/*
* If we have to synchronize the registry hive we
* want to look for dirty blocks to reflect the new
* updates done to the hive. Otherwise just write
* all the blocks as if we were doing a regular
* hive write.
*/
if (OnlyDirty)
{
/* Check if the block is clean or we're past the last block */
LastIndex = BlockIndex;
BlockIndex = RtlFindSetBits(&RegistryHive->DirtyVector, 1, BlockIndex);
if (BlockIndex == ~HV_CLEAN_BLOCK || BlockIndex < LastIndex)
{
break;
}
}
/* Get the block and offset position */
Block = (PVOID)RegistryHive->Storage[Stable].BlockList[BlockIndex].BlockAddress;
FileOffset = (BlockIndex + 1) * HBLOCK_SIZE;
/* Now write this block to primary hive file */
Success = RegistryHive->FileWrite(RegistryHive, FileType,
&FileOffset, Block, HBLOCK_SIZE);
if (!Success)
{
DPRINT1("Failed to write hive block to primary hive file (block 0x%p, block index 0x%x)\n",
Block, BlockIndex);
return FALSE;
}
/* Go to the next block */
BlockIndex++;
}
/*
* We wrote all the hive contents to the file, we
* must flush the changes to disk now.
*/
Success = RegistryHive->FileFlush(RegistryHive, FileType, NULL, 0);
if (!Success)
{
DPRINT1("Failed to flush the primary hive\n");
return FALSE;
}
/*
* Increment the secondary sequence number and
* update the checksum. A successful hive write
* transaction is when both of sequences are the
* same, indicating the write operation didn't
* fail.
*/
RegistryHive->BaseBlock->Sequence2++;
RegistryHive->BaseBlock->CheckSum = HvpHiveHeaderChecksum(RegistryHive->BaseBlock);
/* Write hive block */
FileOffset = 0;
Success = RegistryHive->FileWrite(RegistryHive, FileType,
&FileOffset, RegistryHive->BaseBlock,
sizeof(HBASE_BLOCK));
if (!Success)
{
DPRINT1("Failed to write the base block header to primary hive (secondary sequence)\n");
return FALSE;
}
/* Flush the hive immediately */
Success = RegistryHive->FileFlush(RegistryHive, FileType, NULL, 0);
if (!Success)
{
DPRINT1("Failed to flush the primary hive\n");
return FALSE;
}
return TRUE;
}
/* PUBLIC FUNCTIONS ***********************************************************/
/**
* @brief
* Synchronizes a registry hive with latest updates
* from dirty data present in volatile memory, aka RAM.
* It writes both to hive log and corresponding primary
* hive. Syncing is done on request by the system during
* a flush occurrence.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where syncing is
* to be performed.
*
* @return
* Returns TRUE if syncing has succeeded, FALSE otherwise.
*/
BOOLEAN
CMAPI
HvSyncHive(
_In_ PHHIVE RegistryHive)
{
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
BOOLEAN HardErrors;
#endif
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->Signature == HV_HHIVE_SIGNATURE);
/* Avoid any write operations on volatile hives */
if (RegistryHive->HiveFlags & HIVE_VOLATILE)
{
DPRINT("Hive 0x%p is volatile\n", RegistryHive);
return TRUE;
}
/*
* Check if there's any dirty data in the vector.
* A space with clean blocks would be pointless for
* a log because we want to write dirty data in and
* sync up, not clean data. So just consider our
* job as done as there's literally nothing to do.
*/
if (RtlFindSetBits(&RegistryHive->DirtyVector, 1, 0) == ~HV_CLEAN_BLOCK)
{
DPRINT("The dirty vector has clean data, nothing to do\n");
return TRUE;
}
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
/* Disable hard errors before syncing the hive */
HardErrors = IoSetThreadHardErrorMode(FALSE);
#endif
#if !defined(_BLDR_)
/* Update hive header modification time */
KeQuerySystemTime(&RegistryHive->BaseBlock->TimeStamp);
#endif
/* Update the hive log file if present */
if (RegistryHive->Log)
{
if (!HvpWriteLog(RegistryHive))
{
DPRINT1("Failed to write a log whilst syncing the hive\n");
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
IoSetThreadHardErrorMode(HardErrors);
#endif
return FALSE;
}
}
/* Update the primary hive file */
if (!HvpWriteHive(RegistryHive, TRUE, HFILE_TYPE_PRIMARY))
{
DPRINT1("Failed to write the primary hive\n");
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
IoSetThreadHardErrorMode(HardErrors);
#endif
return FALSE;
}
/* Update the alternate hive file if present */
if (RegistryHive->Alternate)
{
if (!HvpWriteHive(RegistryHive, TRUE, HFILE_TYPE_ALTERNATE))
{
DPRINT1("Failed to write the alternate hive\n");
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
IoSetThreadHardErrorMode(HardErrors);
#endif
return FALSE;
}
}
/* Clear dirty bitmap. */
RtlClearAllBits(&RegistryHive->DirtyVector);
RegistryHive->DirtyCount = 0;
#if !defined(CMLIB_HOST) && !defined(_BLDR_)
IoSetThreadHardErrorMode(HardErrors);
#endif
return TRUE;
}
/**
* @unimplemented
* @brief
* Determines whether a registry hive needs
* to be shrinked or not based on its overall
* size of the hive space to avoid unnecessary
* bloat.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where hive
* shrinking is to be determined.
*
* @return
* Returns TRUE if hive shrinking needs to be
* done, FALSE otherwise.
*/
BOOLEAN
CMAPI
HvHiveWillShrink(
_In_ PHHIVE RegistryHive)
{
/* No shrinking yet */
UNIMPLEMENTED_ONCE;
return FALSE;
}
/**
* @brief
* Writes data to a registry hive. Unlike
* HvSyncHive, this function just writes
* the wholy registry data to a primary hive,
* ignoring if a certain data block is dirty
* or not.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where data
* is be written into.
*
* @return
* Returns TRUE if hive writing has succeeded,
* FALSE otherwise.
*/
BOOLEAN
CMAPI
HvWriteHive(
_In_ PHHIVE RegistryHive)
{
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->Signature == HV_HHIVE_SIGNATURE);
#if !defined(_BLDR_)
/* Update hive header modification time */
KeQuerySystemTime(&RegistryHive->BaseBlock->TimeStamp);
#endif
/* Update hive file */
if (!HvpWriteHive(RegistryHive, FALSE, HFILE_TYPE_PRIMARY))
{
DPRINT1("Failed to write the hive\n");
return FALSE;
}
return TRUE;
}
/**
* @brief
* Writes data to an alternate registry hive.
* An alternate hive is usually backed up by a primary
* hive. This function is tipically used to force write
* data into the alternate hive if both hives no longer match.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where data
* is to be written into.
*
* @return
* Returns TRUE if hive writing has succeeded,
* FALSE otherwise.
*/
BOOLEAN
CMAPI
HvWriteAlternateHive(
_In_ PHHIVE RegistryHive)
{
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->Signature == HV_HHIVE_SIGNATURE);
ASSERT(RegistryHive->Alternate);
#if !defined(_BLDR_)
/* Update hive header modification time */
KeQuerySystemTime(&RegistryHive->BaseBlock->TimeStamp);
#endif
/* Update hive file */
if (!HvpWriteHive(RegistryHive, FALSE, HFILE_TYPE_ALTERNATE))
{
DPRINT1("Failed to write the alternate hive\n");
return FALSE;
}
return TRUE;
}
/**
* @brief
* Synchronizes a hive with recovered
* data during a healing/resuscitation
* operation of the registry.
*
* @param[in] RegistryHive
* A pointer to a hive descriptor where data
* syncing is to be done.
*
* @return
* Returns TRUE if hive syncing during recovery
* succeeded, FALSE otherwise.
*/
BOOLEAN
CMAPI
HvSyncHiveFromRecover(
_In_ PHHIVE RegistryHive)
{
ASSERT(!RegistryHive->ReadOnly);
ASSERT(RegistryHive->Signature == HV_HHIVE_SIGNATURE);
/* Call the private API call to do the deed for us */
return HvpWriteHive(RegistryHive, TRUE, HFILE_TYPE_PRIMARY);
}
/* EOF */