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
- 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.
- 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.
- 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
On current master, ReactOS faces these problems:
- ObCreateObject charges both paged and non paged pool a size of TOKEN structure, not the actual dynamic contents of WHAT IS inside a token. For paged pool charge the size is that of the dynamic area (primary group + default DACL if any). This is basically what DynamicCharged is for.
For the non paged pool charge, the actual charge is that of TOKEN structure upon creation. On duplication and filtering however, the paged pool charge size is that of the inherited dynamic charged space from an existing token whereas the non paged pool size is that of the calculated token body
length for the new duplicated/filtered token. On current master, we're literally cheating the kernel by charging the wrong amount of quota not taking into account the dynamic contents which they come from UM.
- Both DynamicCharged and DynamicAvailable are not fully handled (DynamicAvailable is pretty much poorly handled with some cases still to be taking into account). DynamicCharged is barely handled, like at all.
- As a result of these two points above, NtSetInformationToken doesn't check when the caller wants to set up a new default token DACL or primary group if the newly DACL or the said group exceeds the dynamic charged boundary. So what happens is that I'm going to act like a smug bastard fat politician and whack
the primary group and DACL of an token however I want to, because why in the hell not? In reality no, the kernel has to punish whoever attempts to do that, although we currently don't.
- The dynamic area (aka DynamicPart) only picks up the default DACL but not the primary group as well. Generally the dynamic part is composed of primary group and default DACL, if provided.
In addition to that, we aren't returning the dynamic charged and available area in token statistics. SepComputeAvailableDynamicSpace helper is here to accommodate that. Apparently Windows is calculating the dynamic available area rather than just querying the DynamicAvailable field directly from the token.
My theory regarding this is like the following: on Windows both TokenDefaultDacl and TokenPrimaryGroup classes are barely used by the system components during startup (LSASS provides both a DACL and primary group when calling NtCreateToken anyway). In fact DynamicAvailable is 0 during token creation, duplication and filtering when inspecting a token with WinDBG. So
if an application wants to query token statistics that application will face a dynamic available space of 0.
The current state of Security manager's code is kind of a mess. Mainly, there's code scattered around places where they shouldn't belong and token implementation (token.c) is already of a bloat in itself as it is. The file has over 6k lines and it's subject to grow exponentially with improvements, features, whatever that is.
With that being said, the token implementation code in the kernel will be split accordingly and rest of the code moved to appropriate places. The new layout will look as follows (excluding the already existing files):
- client.c (Client security implementation code)
- objtype.c (Object type list implementation code -- more code related to object types will be put here when I'm going to implement object type access checks in the future)
- subject.c (Subject security context support)
The token implementation in the kernel will be split in 4 distinct files as shown:
- token.c (Base token support routines)
- tokenlif.c (Life management of a token object -- that is Duplication, Creation and Filtering)
- tokencls.c (Token Query/Set Information Classes support)
- tokenadj.c (Token privileges/groups adjusting support)
In addition to that, tidy up the internal header and reorganize it as well.
The problem is that EndMem is changed to point to the DynamicPart of
the token, but the code after that expects it to still point into the
VariablePart instead.
Problem fixed by moving the insertion of RestrictedSids much sooner
(where the original ones are also being copied).
Shared locking must be used on the source token as it is accessed for
reading only. This fixes in particular the kmtest SeTokenFiltering that
would hang otherwise on a (wrong) exclusive locking.
- SepPerformTokenFiltering(): Always shared-lock the source token.
Its callers (NtFilterToken and SeFilterToken) just need to sanitize and
put the parameters in correct form before calling this helper function.
- Sync comments in NtFilterToken() with SeFilterToken().
This function is either called inter-kernel (in which case, all
parameters must be valid, and if not, we have to bugcheck), or, it
is called with **captured** parameters (from NtFilterToken) and those
latter ones are now expected to be valid and reside in kernel-mode.
Finally, data copied between token structures reside in kernel-mode
only and again are expected to be valid (if not, we bugcheck).
- The ACL is however not validated when the function is called within
kernel mode and no capture is actually being done.
- Simplify aspects of the function (returning early when possible).
Implement initial token debug code. For now debug information that is being tracked are: process image file name, process and thread client IDs and token creation method. More specific debug code can be added later only if needed.
As for the token creation method, this follows the same principle as on Windows where the creation method is defined by a value denoting the first letter of the said method of creation. That is, 0xC is for token creation, 0xD is for token duplication and 0xF is for token filtering. The debug field names are taken from Windows PDB symbols for WinDBG debug extension support purposes. The names must not be changed!
This reverts 8479509 commit which pretty much does nothing at all (the captured pointer is NULL within the stack of the function has no effect outside of the function). My mistake, sorry.
Whenever a captured security property such as privilege or SID is released, we must not have such captured property point at random address in memory but rather we must assign it as NULL after it's been freed from pool memory. This avoids potential double-after-free situations where we might release a buffer twice.
This is exactly the case with token filtering.
This implements the support of token filtering within the kernel, where the kernel can create restricted tokens of regular ones on demand by the caller. The implementation can be accessed thorough a NT syscall, NtFilterToken, and a kernel mode routine, SeFilterToken.
The continue statements do not server any useful purpose in these loops so they're basically pointless. These have been introduced by mistake so my bad.
A scenario where it happens that an access token belongs to an administrators group but it's disabled (that is, SeAliasAdminsSid has no attributes or it doesn't have SE_GROUP_ENABLED turn ON), the function removes this group from the token but still has TOKEN_HAS_ADMIN_GROUP flag which can lead to erratic behavior across the kernel and security modules -- implying that the token still belongs to administrators group.
This is an oversight from my part.
This implements the EffectiveOnly option of SepDuplicateToken routine (used by NtDuplicateToken syscall and other functions alike) which makes the access token effective by removing the disabled parts like privileges and groups.
When creating or duplicating an access token object, make sure that the logon session is getting referenced by the token must be inserted onto the logon reference member (a.k.a LogonSession) for proper logon session referencing tracking.
Also when a token object is about to be destroyed or that we are taking away a reference session from it, we must ensure that the referenced logon session data gets removed from the token in question.
CORE-17700
When duplicating an access token, the authentication ID is already copied from the existing token to the new one anyway so there's no point on having the commented call still left in the code.
- Remove a redundant call of ObReferenceObjectByHandle. Not only it didn't make much sense (we reference the object from thread handle and the new thread object referencing the same handle!), specifying a request access of THREAD_ALL_ACCESS for the thread object is kind of suspicious and all of these access rights are unwanted.
- Add some failure checks involving the CopyOnOpen code paths
- Add some DPRINT1 debug prints (concerning the CopyOnOpen code paths as usual)
In addition to that, here are some stuff done in this commit whilst testing:
- ICIF_QUERY_SIZE_VARIABLE and friends were badly misused, they should be used only when an information class whose information length size is dyanmic and not fixed. By removing such flags from erroneous classes, this fixes the STATUS_INFO_LENGTH_MISMATCH testcases.
- Use CHAR instead of UCHAR for classes that do not need alignment probing, as every other class in the table do, for the sake of consistency.
- ProcessEnableAlignmentFaultFixup uses BOOLEAN as type size, not CHAR. This fixes a testcase failure on ROS.
- Check for information length size before proceeding further on querying the process' cookie information.
- ProcessHandleTracing wants an alignment of a ULONG, not CHAR.
- Move PROCESS_LDT_INFORMATION and PROCESS_LDT_SIZE outside of NTOS_MODE_USER macro case. This fixes a compilation issue when enabling the alignment probing. My mistake of having them inside NTOS_MODE_USER case, sorry.
- On functions like NtQueryInformationThread and the Process equivalent, complete probing is not done at the beginning of the function, complete probing including if the buffer is writable alongside with datatype misalignment check that is. Instead such check is done on each information class case basis. With that said, we have to explicitly tell DefaultQueryInfoBufferCheck if we want a complete probing or not initially.
A few of these classes have fixed size lengths, the rest are arbitrary. Also the TokenAuditPolicy class hasn't a size length type specified in the table, which is wrong (and move the corresponding TOKEN_AUDIT_POLICY_INFORMATION structure into the private header).
Implement SepImpersonateAnonymousToken private helpers, which is necessary for the complete implementation of NtImpersonateAnonymousToken function and thus finally we're able to impersonate the anonymous logon token.
* Guard the token in a lock whilst querying stuff
* Remove the piece of code that checks if the information class provided is above the maximum information class threshold. That code literally duplicates the inner functionality of the default case in the switch block, where the code falls in that case if an invalid information class is provided anyway.
* Remove the redundant information classes. Internally, this function in Windows has 12 switch case blocks (11 token info classes + the default case) and the other classes are supported in NtQueryInformationToken only so it doesn't make any logical sense to keep them in the codebase.
* Annotate the argument parameters with SAL and add documentation header
This function is used during the Security kernel module phase initialisation to set up the system process token which the phase initialisation procedure in itself is stored in the INIT section. With that being said, do the same for SepCreateSystemProcessToken too and add a header documentation as an addition.
These private functions are needed to set up two different kinds of system's anonymous logon tokens: one that includes everyone in the group and the other that doesn't. These functions are needed as next step closer to the
implementation of NtImpersonateAnonymousToken system call.
* Implement SepCompareSidAndAttributesFromTokens and SepComparePrivilegeAndAttributesFromTokens functions for array elements comparison
* Implement the token comparison code in SepCompareTokens function
* Add a missing PAGED_CODE() in SepCompareTokens as most of the token comparison code is paged
* Use SAL annotations for SepCompareTokens and NtCompareTokens
In Windows Server 2003 the lock is initialised on a per-token basis, that is, the lock resource is created in SepDuplicateToken() and SepCreateToken() functions. This ensures that the lock initialisation is done locally for the specific token thus avoiding the need of a global lock.
- Change INIT_FUNCTION and INIT_SECTION to CODE_SEG("INIT") and DATA_SEG("INIT") respectively
- Remove INIT_FUNCTION from function prototypes
- Remove alloc_text pragma calls as they are not needed anymore