- Annotate the functions in query.c file with SAL2 of which they weren't annotated before
- Use _Out_writes_bytes_to_opt_ to further clarify the output parameter is being written to it based on the length size provided.
This is so the code analyzer understands such a parameter is being written into only the specific amount of bytes.
The WDM header contains power manager related GUIDs that were declared but never initialized properly due to the fact the initguid.h header wasn't at the top.
This patch fixes a linker error in the kernel where GUIDs like GUID_LIDSWITCH_STATE_CHANGE are used.
It's a hotfix for 624c3fd.
This library aims to include all the public and global power manager related GUID identifiers into one shared library, of which they can be accessed across multiple modules of ReactOS, e.g. the kernel, ACPI, PCI, et al.
This patch is needed for the development of the Power Manager (#5719) to continue.
CORE-18969
Short answer: our UI sucks bolas rojas.
Long answer: when the NT kernel informs the user-mode part of the system that the battery is no longer charging, the machine is directly powered up by the AC adapter.
This is understood by determining the presence of AC_LINE_ONLINE status bit in ACLineStatus member field, which is a Windows API construct.
In the NT world this is understood by checking the power state returned by the BATTERY_STATUS structure.
What's happening right now is that when the battery is fully charged, ROS UI simply displays "100% remaining" implying the battery is about to discharge, which is not the case.
This is extremely confusing to the user. AND WORST PART IS THAT IT'S XP/2003 DESIGN, AND I HATE IT UGGGHHH.
With this patch we're leaning towards Windows 10/11 way of informing the user the battery is fully charged. VIVA LA NT6!
CORE-18969
CORE-19452
- Declare CMBATT_DISCHARGE_TIME and CMBATT_CAPACITY_BOGUS constructs
- Determine if the battery was already discharging and if not, update the time when it's being discharged
- Fix the condition where it checks if the battery has been discharging for quite some time
- Default the time to BATTERY_UNKNOWN_TIME if querying the estimated battery time request fails or if the battery has just started discharging not over 15 seconds
CORE-18969
CORE-19452
Windows SDKs define this constant to 0xFFFFFFFF but we define it to 0x80000000.
As a result, when our COMPBATT driver is being tested on Windows (namely XP, Vista and 7), BATTERY_UNKNOWN_TIME is not interpreted as UNKNOWN TIME but entirely something else.
CORE-18969
CORE-19452
IoInitializeRemoveLock expects an allocation tag to be provided when it allocates debug data in the kernel.
Passing 0 leads to a bunch of ASSERTs in the kernel as such data is allocated by ExAllocatePoolWithTag of which a tag has to be supplied, it's not optional.
- Introduce some new constructs
- Annotate the function prototypes with SAL2
- Re-structure & remove some useless fields in COMPBATT_DEVICE_EXTENSION and COMPBATT_BATTERY_DATA
_BIX is basically _BIF but with more information added, such as cycle count, measurement capacity accuracy and whatnot.
Starting with ACPI 4.0 _BIF is rendered obsolete and as a matter of fact a lot of modern hardware fill their ACPI machine data to _BIX.
ReactOS must go forward and beyond, compatibility with _BIF is kept. NOTE that a machine can ONLY support one battery static information method!
CORE-18969
CORE-19452
We do have IDS_PWR_HOURS_REMAINING and IDS_PWR_MINUTES_REMAINING string resources but they're never used programmatically.
Display the estimated battery time ONLY if the returned time is not unknown.
CORE-18969
CORE-19452
BatteryClassStatusNotify is used by battery miniport drivers to notify the Battery Class of a status change. This can either be a battery status change or battery tag assignation, depending on what the device extension (namely the composite battery) waits for.
We do have implementation for EVENT_BATTERY_STATUS but not for EVENT_BATTERY_TAG. What happens is when BatteryClassIoctl fails to query the battery tag because it has not yet been assigned, the thread is stuck on waiting for the event object to be signaled, forever.
This tipically happens when a timeout of -1 (meaning the calling thread must wait indefinitely) is supplied. The composite battery driver (COMPBATT) is responsible to signal the Battery Class when a CM (Control Method) ACPI battery receives a tag, which then this function will signal the event.
CORE-18969
CORE-19452
ReactOS (like any other OSes) expects power data to be represented in milliwatts per hour, not in milliamps per hour.
Currently CMBATT defaults the stats to unknown values, if that's the case, and there are a bunch of machines that do report their data from _BIF ACPI method in ampere.
CORE-18969
CORE-19452
KeWaitForSingleObject takes 100ns unit for timeout. Both IOCTL_BATTERY_QUERY_TAG and IOCTL_BATTERY_QUERY_STATUS take a wait for the timeout in milliseconds.
Supposedly a miniport driver wants to supply a wait of 5000 ms (which is equivalent to 5 s), the miniport driver WON'T BE WAITING 5 seconds but 0.5!!!
CORE-18969
CORE-19452
Support for system batteries in ReactOS is really minimal to the point of non-existing. We are detecting the presence of any upcoming battery but since there's lacking in critical code that deals with communication
between PO and the battery class driver as the battery systray icon uses GetSystemPowerStatus to gather battery info which in turn inquires the power manager via NtPowerInformation(SystemBatteryState), we have
to report to the user that the remaining capacity is unknown rather than returning a pseudo capacity value.
Technically this so called "pesudo" value is just a construct denoted as BATTERY_PERCENTAGE_UNKNOWN. Not reporting the actual remaining capacity makes sense, as there could be a scenario where the battery may not
properly report its real datum, therefore it's best to be honest to the user what's really going on.
CORE-19452
CORE-18969
In order for the NT power manager to interact with the Win32 subsystem (thus the whole rest of the system), the Win32 kernel-mode subsystem provides a mechanism that communicates with the kernel power manager via power callouts (aka power requests as per Windows' PDB symbols).
Such mechanism enters in action as soon as Win32 callout routines are estabilished with the PsEstablishWin32Callouts() function.
The NT power manager, the power policy manager respectively, invokes a power callout to denote an exceptional phenomena as a result of power policies or capabilities changes, turning ON/OFF the display, a system time change has occurred, etc.
Such scenarios are described as power events of which the NT power manager sends a WIN32_POWEREVENT_PARAMETERS packet to Win32k via the estabilished "PowerEventCallout" pointer function callout.
For other callouts that inform the Win32 subsystem of impeding power state changes across the system or devices, these are sent as WIN32_POWERSTATE_PARAMETERS packets with its own separate callout.
The purpose of such mechanism is to give Win32k the opportunity to do power related tasks and alert every application of such power events in accordance with what it gets notified by the NT power manager.
Currently this patch stubplements this mechanism in ROS, it is only just the barebones for now. The development of the Win32 power manager will go in parallel with the kernel power manager development (expand, improve, fix the code of issues that whatever may arise).
So far only the PsW32SystemTime power event is implemented for the moment being. This work was decoupled from PR #5719 to avoid clobbering it too much.
=== TODO ===
- Implement power states management communication with the kernel power manager
- Implement the rest of the power events in IntHandlePowerEventWorker
- Implement power event handling in CSRSS (or WinSrv?) which handles any of the events that could not be handled by Win32k otherwise
- Estabilish the power state callout in PsEstablishWin32Callouts() (currently there is no a pointer function that gets assigned to such callout)
CORE-18969
The PR #6649 which fixed an issue with orphaned KCBs leaking in memory which also pointed to unloaded registry hives, it also brought a problem.
In CmpEnumerateOpenSubKeys there is a risk of getting hit by a deadlock as we enumerate the cache table to remove empty cache entries.
Fundamentally CmpEnumerateOpenSubKeys locks down a KCB from cache for exclusive use in order to tear down its contents from memory but it doesn't address the fact a KCB might have already been locked in the same calling thread, leading to a recursion.
This leads to random hangs when unloading a hive during system startup (tipically on a clean install).
The solution here is to simply lock the whole registry when we unload a hive so that we don't have to worry the KCBs are getting tampered by anybody else. This also simplifies the code.
Although locking the entire registry while other apps are doing registry related operations to other hives can cause overhead. If this turns out to be bad then we have to rethink the locking mechanism here.
CORE-19539
As the commit title says, the point of registering a device interface with ACPI fans is to receive incoming PnP notifications of incoming ACPI fan drivers so that the power manager can connect to them by creating a power device policies dedicated to them during power manager initialization.
CORE-18969
A hive whose KCBs have a reference count of 0, meaning nobody is using these keys anymore, will not get removed from the cache table.
As a result during a normal hive unloading operation you will get orphaned KCBs which results in an unload failure.
This is wrong, because this is what a normal hive unloading is supposed to do. What it cannot do of course is that it cannot
scramble the references of opened keys by the users who use the Registry, as it is the job of force unloading mechanism to do that.
Also remove a misleading debug print. Force unloading works as intended by scrambling the references of keys and marking the KCB for deletion,
which is what how a force unload works. Namely Windows does exactly that.
CORE-10705
- Annotate the CmpEnumerateOpenSubKeys function with SAL2
- When removing an orphaned cached KCB, ensure that it is locked before clearing it from cache table entries
Sometimes repairing a broken hive with a hive log does not always guarantee the hive
in question has fully recovered. In worst cases it could happen the LOG itself is even
corrupt too and that would certainly lead to a total unbootable system. This is most likely
if the victim hive is the SYSTEM hive.
This can be anyhow solved by the help of a mirror hive, or also called an "alternate hive".
Alternate hives serve the purpose as backup hives for primary hives of which there is still
a risk that is not worth taking. For now only the SYSTEM hive is granted the right to have
a backup alternate hive.
=== NOTE ===
Currently the SYSTEM hive can only base upon the alternate SYSTEM.ALT hive, which means the
corresponding LOG file never gets updated. When time comes the existing code must be adapted
to allow the possibility to use .ALT and .LOG hives simultaneously.
As we iterate over the chunk hive data pointer for hive bins that we are going
to enlist, we might encounter one or several bins that would get corrupted
during a premature abortion of a registry writing operation such as due to
a power outage of the system, hardware malfunction, etc.
Corruption at the level of hive bins is nasty because they contain actual cell
data of registry information such as keys, values etc. Assuming a bin is corrupt
in part we can fix it by recovering some of the bin properties that, theoretically,
could be fixed -- namely the signature, size and offset.
For size and offset we are more or less safe because a bin typically has a size
of a block, and the offset is the coordinate index of where a hive bin should lay at.
If FreeLdr performed recovery against the SYSTEM hive with a log, all of its data is only present in volatile memory thus dirty. So the kernel is responsible to flush all the data that's been recovered within the SYSTEM hive into the backing storage.
The newly implemented code for registry recovery makes the FreeLdr binary to grow
in size, to the point that it would BSOD because the PE image is too big.
For now we have to temporarily disable any of the newly added code, until
either FreeLdr is split into a basic PE bootloader image itself and a
"FreeLdrlib" that is used by the PE image to access various bootloader APIs
or another proper solution is found.
Validate the SYSTEM hive with CmCheckRegistry and purge volatile data with the same function when initializing a hive descriptor for SYSTEM.
Also implement SYSTEM recovery code that takes use of SYSTEM log in case something is fishy with the hive. If hive repair doesn't have fully recovered the SYSTEM hive, FreeLdr will load the alternate variant of the SYSTEM hive, aka SYSTEM.ALT.
If FreeLdr repairs the hive with a LOG, it will mark it with HBOOT_BOOT_RECOVERED_BY_HIVE_LOG on BootRecover field of the header. All the recovered data that is present as dirty in memory will have to be flushed by the kernel once it is in charge of the system.
Otherwise if the system boot occurred by loading SYSTEM.ALT instead, FreeLdr will mark HBOOT_BOOT_RECOVERED_BY_ALTERNATE_HIVE, the kernel will start recovering the main hive as soon as it does any I/O activity into it.
Thanks to CmCheckRegistry, the function can perform volatile data purging upon boot which this removes old hacky CmPrepareHive code. This also slightly refactors HvInitialize making it more proper.
=== DOCUMENTATION REMARKS ===
This implements (also enables some parts of code been decayed for years) the transacted writing of the registry. Transacted writing (or writing into registry in a transactional way) is an operation that ensures the successfulness can be achieved by monitoring two main points.
In CMLIB, such points are what we internally call them the primary and secondary sequences. A sequence is a numeric field that is incremented each time a writing operation (namely done with the FileWrite function and such) has successfully completed.
The primary sequence is incremented to suggest that the initial work of syncing the registry is in progress. During this phase, the base block header is written into the primary hive file and registry data is being written to said file in form of blocks. Afterwards the seconady sequence
is increment to report completion of the transactional writing of the registry. This operation occurs in HvpWriteHive function (invoked by HvSyncHive for syncing). If the transactional writing fails or if the lazy flushing of the registry fails, LOG files come into play.
Like HvpWriteHive, LOGs are updated by the HvpWriteLog which writes dirty data (base block header included) to the LOG themselves. These files serve for recovery and emergency purposes in case the primary machine hive has been damaged due to previous forced interruption of writing stuff into
the registry hive. With specific recovery algorithms, the data that's been gathered from a LOG will be applied to the primary hive, salvaging it. But if a LOG file is corrupt as well, then the system will perform resuscitation techniques by reconstructing the base block header to reasonable values,
reset the registry signature and whatnot.
This work is an inspiration from PR #3932 by mrmks04 (aka Max Korostil). I have continued his work by doing some more tweaks and whatnot. In addition to that, the whole transaction writing code is documented.
=== IMPORTANT NOTES ===
HvpWriteLog -- Currently this function lacks the ability to grow the log file size since we pretty much lack the necessary code that deals with hive shrinking and log shrinking/growing as well. This part is not super critical for us so this shall be left as a TODO for future.
HvLoadHive -- Currently there's a hack that prevents us from refactoring this function in a proper way. That is, we should not be reading the whole and prepare the hive storage using HvpInitializeMemoryHive which is strictly used for HINIT_MEMORY but rather we must read the hive file block by block
and deconstruct the read buffer from the file so that we can get the bins that we read from the file. With the hive bins we got the hive storage will be prepared based on such bins. If one of the bins is corrupt, self healing is applied in such scenario.
For this matter, if in any case the hive we'll be reading is corrupt we could potentially read corrupt data and lead the system into failure. So we have to perform header and data recovery as well before reading the whole hive.
In addition to that, in some functions like CmFlushKey, CmSaveKey and CmSaveMergedKeys we must validate the underlying hives as a matter of precaution that everything is alright and we don't fuck all the shit up.
CmCheckRegistry is a function that provides the necessary validation checks for a registry hive. This function usually comes into action when logs have been replayed for example, or when a registry hive internals have changed such as when saving a key, loading a key, etc.
This commit implements the whole Check Registry infrastructure (cmcheck.c) in CMLIB library for ease of usage and wide accessibility across parts of the OS. In addition, two more functions for registry checks are also implemented -- HvValidateHive and HvValidateBin.
Instead of having the CmCheckRegistry implementation in the kernel, it's better to have it in the Configuration Manager library instead (aka CMLIB). The benefits of having it in the library are the following:
- CmCheckRegistry can be used in FreeLdr to fix the SYSTEM hive
- It can be used on-demand in the kernel
- It can be used for offline registry repair tools
- It makes the underlying CmCheckRegistry implementation code debug-able in user mode
CORE-9195
CORE-6762
This implements cmheal.c file which provides the basic registry self-heal infrastructure needed by the public CmCheckRegistry function. The infrastructure provides a range of various self-heal helpers for the hive, such as subkey, class, values and node healing functions.
Add these NTSTATUS codes in the CMLIB library. STATUS_INVALID_PARAMETER will be used mostly for HvInitialize function, STATUS_REGISTRY_IO_FAILED for whatever routines that deal with reading or writing into a hive file.
During a I/O failure of whatever kind the upper-level driver, namely a FSD, can raise a hard error and a deadlock can occur. We wouldn't want that to happen for particular files like hives or logs so in such cases we must disable hard errors before toying with hives until we're done.
In addition to that, annotate the CmpFileSetSize function's parameters with SAL.
When shutting down the registry of the system we don't want that the registry in question gets poked again, such as flushing the hives or syncing the hives and respective logs for example. The reasoning behind this is very simple, during a complete shutdown the system does final check-ups and stuff until the computer
shuts down.
Any writing operations done to the registry can lead to erratic behaviors. CmShutdownSystem call already invokes a final flushing of all the hives on the backing storage which is more than enough to ensure consistency of the last session configuration. So after that final flushing, mark HvShutdownComplete as TRUE indicating
that any eventual flushing or syncying (in the case where HvSyncHive gets called) request is outright ignored.
=== DOCUMENTATION REMARKS ===
HBOOT_TYPE_REGULAR and HBOOT_TYPE_SELF_HEAL are boot type values set up by the CMLIB library (for the BootType field respectively). HBOOT_TYPE_REGULAR indicates a normal system boot whereas HBOOT_TYPE_SELF_HEAL indicates the system boot is assisted within self healing mode.
Whether the former or the latter value is set it's governed by both the kernel and the bootloader. The bootloader and the kernel negotiate together to determine if any of the registry properties (the hive, the base block, the registry base, etc) are so severed from corruption or not. In extreme cases where
registry healing is possible, the specific base block of the damaged hive will have its flags marked with HBOOT_TYPE_SELF_HEAL. At this point the boot phase procedure is orchestrated since the boot phase no longer goes on the default path but it's assisted, as I have already said above.
HBOOT_NO_BOOT_RECOVER, HBOOT_BOOT_RECOVERED_BY_HIVE_LOG and HBOOT_BOOT_RECOVERED_BY_ALTERNATE_HIVE on the other hand are identifiers for the BootRecover field of the BASE_BLOCK header structure. These are used exclusively by FreeLdr to tell the kernel if the bootloader recovered the SYSTEM hive or not. In case where the bootloader did recover the SYSTEM hive,
the kernel will perform a flush request on the dirty data down to disk. The (almost) worse case FreeLdr could not repair the main hive by applying log data, it will load the alternate mirror version of the hive.
In addition to that, declare other miscellaneous CMLIB identifiers for log transaction writes purposes.
NtSetDefaultLocale and ExpSetCurrentUserUILanguage do not probe the given locale or language ID,
and as a result of that these functions would happily take any given argument. This is problematic
because overwriting NLS data (specifically the Default registry key value as its gets set by the
NtSetDefaultLocale syscall itself) with garbage stuff, rendering the system completely unbootable.
In addition to that, these functions do not check the captured language/locale ID against pre-determined
locales or languages pre-installed in the system. This basically means an ID of 1, for example, is still
valid because it is not bogus albeit there is no such a locale of an ID of 1. That value would get passed
to the Default value key and that renders the system unbootable as well.
CORE-18100
They can be spammy. Also clarify these debug prints, because some people
think that "failed to grant access rights" means there's something wrong
in the core access check functions.
Temporarily add the local group to the system token so that Virtualbox
GA services can properly set up network drives for shared folders.
What happens is that a security descriptor has a DACL with only one ACE
that grants access to Local SID (presumably coming from Vbox?)
but the client token is that of the service which is a SYSTEM token.
Perhaps we are not impersonating the right user or whatever else.
This is only a temporary placebo, until a proper solution is found.
CORE-18250
Certain apps such as AIM installer passes an empty generic mapping (this can
be understood with their generic masks set to 0) and our code tries to map
the access right from an ACE with the mapping provided by AccessCheck.
This can lead to a bug where we would not be able to decode the generic right
from an ACE as we need a proper generic mapping in order to do so. A mask
right that is not decoded it cannot be used to mask out the remaining rights,
further resulting into a denied access right.
What Windows does instead is they are mapping the ACE's rights in another place,
presumably when setting security data to an object, and they are using the
generic mapping passed by the kernel.
What we can do for the time being is to temporarily grant access to the client,
but only if they are an administrator.
CORE-18576
During an open or create procedure of a registry key, the registry parser grabs
a key control block (KCB) from the parser object and uses its information to do the
necessary work in order to obtain a pointer to the newly created or opened registry key.
However, the registry parsers faces several issues. First, we don't do subkey cache cleaning
information against gathered KCBs so whenever we do a registry parse we end up with KCBs
that have cache inconsistencies. Moreover we don't do any locking of whatever KCB we
are grabing during a parse procedure.
=== PROPOSED CHANGES ===
* Implement CmpComputeHashValue and CmpLookInCache functions. With CmpComputeHashValue we can
compute the convkey hashes of each subkey in the path name of a key so we can lock them
with CmpBuildAndLockKcbArray. CmpLookInCache is a function that searches for the suitable
KCB in the cache. The factors that determine if a KCB is "suitable" are:
-- the currently found KCB in the hash list has the same levels as that of the
given KCB from the parse object;
-- The key names from the computed hash values match with the block name of
the KCB;
-- The currently found KCB is not deleted.
The KCB will be changed if the key path name points to a partial match name in
the cache. The KCB from the parse object will be used if we have a full match
of remaining levels.
* Add missing CMP_LOCK_HASHES_FOR_KCB flags on CmpCreateKeyControlBlock calls
that create KCBs during a parse procedure. Such lock has to be preserved until
we're done with the registry parsing.
* On CmpDoCreateChild, preserve the exclusive lock of the KCB when we are
enlisting the key body.
* On CmpDoCreate, make sure that the passed parent KCB is locked exclusively and
lock the hiver flusher as we don't want the flusher to kick in during a key
creation on the given hive. Cleanup the subkey info when we're creating a key
object. Also implement missing cleanup path codes. Furthermore, avoid key
object creation if the parent KCB is protected with a read-only switch.
* Soft rewrite the CmpDoOpen function, namely how we manage a direct open vs
create KCB on open scenario. When a KCB is found in cache avoid touching
the key node. If the symbolic link has been resolved (aka found) then lock
exclusively the symbolic KCB. Otherwise just give the cached KCB to the caller.
If it were for the caller to request a KCB creation, we must check the passed
KCB from the parser object is locked exclusively, unlike on the case above
the caller doesn't want to create a KCB because there's already one in the cache.
We don't want anybody to touch our KCB while we are still toying with it during
its birth. Furthermore, enlist the key body but mind the kind of lock it's been
used.
* On CmpCreateLinkNode, avoid creating a key object if the parent KCB is protected
with a read-only switch. In addition, add missing hive flusher locks for both
the target hive and its child. Cleanup the subkey information of the KCB when
creating a link node, this ensures our cached KCB data remains consistent.
* Do a direct open on CmpParseKey if no remaining subkey levels have been found
during hash computation and cache lookup, in this case the given KCB is the
block that points to the exact key. This happens when for example someone tried
to call RegOpenKeyExW but submitting NULL to the lpSubKey argument parameter.
CORE-10581
ROSTESTS-198
CmpSecurityMethod is a method used by the Object Manager and called by this
subsystem whenever a security operation has to be done against a key object.
As CmpSecurityMethod is a specific OB construct we should not make any direct
call attempts to CmpSecurityMethod, only OB is responsible for that. This fixes
a deadlock where CmpSecurityMethod acquires a push lock for exclusive access
even though such lock is already acquired by the same calling thread in
CmpDoCreateChild.
This prevents a deadlock in DelistKeyBodyFromKCB when we delete a key
object because of an access check failure during a open procedure of a
registry key, as we are already holding a lock against the target KCB of
the key body.
Whenever a security request is invoked into a key object, such as when requesting
information from its security descriptor, the Object Manager will execute
the CmpSecurityMethod method to do the job.
The problem is that CmpSecurityMethod is not aware if the key control block
of the key body already has a lock acquired which means the function will attempt
to acquire a lock again, leading to a deadlock. This happens if the same
calling thread locks the KCB but it also wants to acquire security information
with ObCheckObjectAccess in CmpDoOpen.
Windows has a hack in CmpSecurityMethod where the passed KCB pointer is ORed
with a bitfield mask to avoid locking in all cases. This is ugly because it negates
every thread to acquire a lock if at least one has it.
The CmpUnLockKcbArray, CmpLockKcbArray and CmpBuildAndLockKcbArray routines
help us to lock KCBs within array so that information remains consistent when
we are doing a cache lookup during a parse procedure of the registry database.
Implement CmpBuildAndLockKcbArray and CmpUnLockKcbArray prototypes, we'll gonna need these
to do the locking/unlocking of KCBs stacked up in an array. In addition implement some CM
constructs specifically for cache lookup implementation (more at documentation remarks).
=== DOCUMENTATION REMARKS ===
CMP_SUBKEY_LEVELS_DEPTH_LIMIT -- This is the limit of up to 32 subkey levels
that the registry can permit. This is used in CmpComputeHashValue to ensure
that we don't compute more than the limit of subkeys we're allowed to.
CMP_KCBS_IN_ARRAY_LIMIT -- This is equal to CMP_SUBKEY_LEVELS_DEPTH_LIMIT
plus the addition by 2. This construct is used as a limit of KCB elements
the array can hold. 2 serves as an additional space for the array (one for
the root object and another one as extra space so we don't blow up the stack
array).
CMP_LOCK_KCB_ARRAY_EXCLUSIVE & CMP_LOCK_KCB_ARRAY_SHARED -- These flags are used exclusively
for CmpBuildAndLockKcbArray and CmpLockKcbArray. Their meaning are obvious.
CM_HASH_CACHE_STACK -- A structure used to store the hashes of KCBs for locking. It is named
"stack" because the way we store the hashes of KCBs is within an auxilliary "outer stack array".
CmpAcquireKcbLockSharedByKey can come in handy for use to lock KCBs by their convkey with a shared lock, specifically we would need this for cache lookup stuff.
Object ACEs are supported starting from Revision 4, the current code checks
if the revision is above Revision 4. An Object ACE has to be strictly set on that revision,
whereas Object ACLs can be of any revision starting from ACL_REVISION4.
Write the necessary ACL validation code for ACEs whose types are ACCESS_ALLOWED_OBJECT_ACE_TYPE
or ACCESS_DENIED_OBJECT_ACE_TYPE. This ensures each created object type ACL has valid ACE
contents.
ACCESS_DENIED_ACE_TYPE, ACCESS_ALLOWED_ACE_TYPE, SYSTEM_AUDIT_ACE_TYPE and
SYSTEM_ALARM_ACE_TYPE belong to the same commonly internal ACE type, aka KNOWN_ACE,
as each of these ACEs have the same structure field offsets.
The only difference are ACCESS_DENIED_OBJECT_ACE_TYPE and ACCESS_ALLOWED_OBJECT_ACE_TYPE
as they have their own internal ACE type variant, the KNOWN_OBJECT_ACE structure.
The general guideline is that public ACE structure variants have to be used elsehwere
such as in UM whilst the kernel has to use the internal known ACE type variants when possible.
- Implement SepDenyAccessObjectTypeResultList, SepAllowAccessObjectTypeResultList,
SepDenyAccessObjectTypeList and SepAllowAccessObjectTypeList. These routines will
be used to grant or deny access to sub-objects of an object in the list.
- Refactor SepAnalyzeAcesFromDacl and SepAccessCheck to accomodate the newly
implemented access check by type mechanism.
- SepAccessCheck will now be SepAccessCheckWorker, a worker helper function that further
abstracts the access check mechanism in the kernel. Whereas the SepAccessCheck name will be
used as a centralized function used by the access check NT system calls.
- Deprecate SepGetSDOwner and SepGetSDGroup in favor of SepGetOwnerFromDescriptor and
SepGetGroupFromDescriptor. The former functions were buggy as they might potentially
return garbage data if either the owner or group were passed as NULL to a security
descriptor, hence a second chance exception fault. This was caught when writing tests
for NtAccessCheckByType.
- Shorten the debug prints by removing the name of the functions, the person who reads
the debugger output has to look at the source code anyway.
This implements various private kernel routines for object type list management
needed for access check code infrastructure. In addition, update the code documentation
and add missing comments.
This function will dump all the access status and granted access rights
of each object list of a list whenever an access check by type (or by type
result list) fails. This is for debugging purposes.
OBJECT_TYPE_LIST_INTERNAL will serve as an internal kernel data structure
to hold validated object type contents that are copied from UM.
The difference between the public and the internal one is that the internal structure has
an additional member for access check rights that have been granted on each
object element in the list.
The newly updated SAL2 annotations reflect those from Process Hacker.
Also these syscalls must have their function's status code checked, as
most of other Native syscalls have them checked.
Handling PnP root driver power IRPs requires that a device object must come up
with a device extension to determine whether it is a function driver and if so,
handle the IRP accordingly.
CORE-18989
And remove the "!NT_SUCCESS(Status)" check which is excessive, the expected
status will always be STATUS_BUFFER_TOO_SMALL anyway. This should fix
some compilation warnings spotted by GCC. Courtesy goes to Hermes for letting
me know of these warnings.
- Refactor most of the code, since there's quite some stuff that don't make much sense.
For instance ImpersonationLevel is basically the requested impersonation level a
server asks for. PsImpersonateClient doesn't explicitly say that SecurityAnonymous
and SecurityIdentification are not allowed. If the server was to give such levels
it simply means it doesn't want to impersonate the client.
Another thing that doesn't make much sense is that we check if the client is
associated with an anonymous token, then avoid impersonating regular anonymous
tokens that weren't created by the system. Only system can create such tokens
and an anonymous token basically means a token with hidden security info.
- Check that the server is within the same client logon session.
- If the server is granted the SeImpersonatePrivilege privilege, allow impersonation
regardless of the conditions we want to check for.
- Update the documentation and code comments.
As it currently stands the PsImpersonateClient routine does the following approach.
If impersonation couldn't be granted to a client the routine will make a copy
of the client's access token. As it makes a copy of the said token PsImpersonateClient
will reference the copied token after impersonation info have been filled out.
In the same code path we are assigning the desired level for impersonation to thread
impersonation info.
This is wrong for two reasons:
- On a copy situation the SeCopyClientToken routine holds a reference as the object
has been created. Referencing it at the bottom of the PsImpersonateClient routine
will make it that the token is referenced twice and whenever a server stops
impersonation the token still has an extra reference count which keeps the token
still alive in object database and memory space.
- If client impersonation is not possible the thread impersonation info should
have been assigned SecurityIdentification level to further indicate that the
actual impersonation of the thread is not currently in force but instead we
are assigning the impersonation level that is supplied by the caller. For instance
if the requested level is SecurityDelegation but impersonation is not possible
the level will be assigned that of SecurityDelegation yet the token has an
impersonation level of SecurityIdentification. This could lead to erratic behaviors
as well as potential impersonation escalation.
Fix the aforementioned issues by avoiding a double reference and properly assign
the impersonation level to SecurityIdentification if the server is not able to
impersonate the target client.
- Add the missing privileges to the SYSTEM privileges which might be needed,
notably SeUndockPrivilege, SeManageVolumePrivilege, SeCreateGlobalPrivilege and
SeImpersonatePrivilege.
Specifically SeImpersonatePrivilege is important here because with it we
allow system components of the core OS to perform certain system tasks.
- Declare the Groups array with a maximum of 3 elements in SepCreateSystemProcessToken
and 1 element in SepCreateSystemAnonymousLogonToken respectively, because previously
this array was oversized with most of free space left as a waste.
- Avoid hardcoding the size value of the Privilege array, instead initialize it
by hand and compute the exact number of elements with RTL_NUMBER_OF.
Due to a update of MSBuild build worker, MSBuild keeps failing which is a nuisance.
Temporarily disable that worker until a proper fix is shipped.
CORE-18911
- Wrap most of the code into a new private routine, SepOpenThreadToken.
And properly fail gracefully if we fail to open a thread's token instead of just keeping going.
- Do not use the same thread object that we have referenced in NtOpenThreadTokenEx
to do a copy of the access token in case we can't open it directly.
Instead we must reference a new object with full access, solely used for
the purpose to do our required operations.
- Add debug prints
CORE-18986
Removing any disabled privileges or groups in the middle of token dynamic
part allocation can pose problems. During the operation of making an access
token as effective, we are toying with the privileges and groups arrays
of the token.
After that we are allocating the dynamic part and set EndMem (the end tail
of the memory part) to that dynamic part, previously it was set to the
variable part. As a matter of fact we are making the token effective in
the middle where EndMem still points to VariablePart, thus DynamicPart
will end up with memory pool blocks butchered in the pool list.
Another problem, albeit not related to the DynamicPart corruption, is that
the code starts iterating over the UserAndGroups array from 0, which is
the actual user. One cannot simply remove the user from the array, so we
have to start looping right from the groups.
Move the token effective code part at the end of the SepDuplicateToken
function, which fixes the random pool corruptions caused by the butchered
DynamicPart.
CORE-18986
The data has to be written into ObjectTypeInfo based on the return length,
not only what is provided by the input buffer length. Fix suggested by
Hermès.
On a x86 system aligning the return length pointer to a 4-byte boundary
works best since pointers in general are 4-byte aligned for x86 systems.
However, what happens on a AMD64 system is that we still align this pointer
to 4-byte, ObjectTypeInfo is a 8-byte pointer and we might write into
the return length past the 4-byte boundary.
If one were to allocate a pool of memory with that length and query all
the object types info and free the said pool of memory thereafter, the
system will crash with BAD_POOL_HEADER because ObQueryTypeInfo overwrote
the return length past the 4-byte boundary length therefore leading up with
corrupted memory blocks in the pool header.
This symptom of BAD_POOL_HEADER happens exactly the same in Windows Server
2003 x64 Edition. Newer versions of Windows like 10 aren't affected.
But, Windows has another bug where they are using MaximumLength for the
calculation of the needed length to be returned to caller. MaximumLength
does not guarantee you that it includes the NULL-terminator in the length
and that potentially leads to a buffer overrun.
Also annotate the ObQueryTypeInfo function with SAL2.
https://processhacker.sourceforge.io/doc/object_8c_source.html (read the
comment in KphObjectTypeInformation).
George Bișoc