reactos/ntoskrnl/se/tokenlif.c
George Bișoc a389f8aa0c
[NTOS:SE] Make an access token effective after the end of token duplication
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
2023-06-04 11:09:22 +02:00

2291 lines
80 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
* PURPOSE: Access token lifetime management implementation (Creation/Duplication/Filtering)
* COPYRIGHT: Copyright David Welch <welch@cwcom.net>
* Copyright 2021-2022 George Bișoc <george.bisoc@reactos.org>
*/
/* INCLUDES *******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
/* DEFINES ********************************************************************/
#define SE_TOKEN_DYNAMIC_SLIM 500
/* PRIVATE FUNCTIONS *********************************************************/
/**
* @brief
* Internal function responsible for access token object creation in the kernel.
* A fully created token objected is inserted into the token handle, thus the handle
* becoming a valid handle to an access token object and ready for use.
*
* @param[out] TokenHandle
* Valid token handle that's ready for use after token creation and object insertion.
*
* @param[in] PreviousMode
* Processor request level mode.
*
* @param[in] DesiredAccess
* Desired access right for the token object to be granted. This kind of access right
* impacts how the token can be used and who.
*
* @param[in] ObjectAttributes
* Object attributes for the token to be created.
*
* @param[in] TokenType
* Type of token to assign upon creation.
*
* @param[in] ImpersonationLevel
* Security impersonation level of token to assign upon creation.
*
* @param[in] AuthenticationId
* Authentication ID that represents the authentication information of the token.
*
* @param[in] ExpirationTime
* Expiration time of the token to assign. A value of -1 means that the token never
* expires and its life depends upon the amount of references this token object has.
*
* @param[in] User
* User entry to assign to the token.
*
* @param[in] GroupCount
* The total number of groups count for the token.
*
* @param[in] Groups
* The group entries for the token.
*
* @param[in] GroupsLength
* The length size of the groups array, pointed by the Groups parameter.
*
* @param[in] PrivilegeCount
* The total number of priivleges that the newly created token has.
*
* @param[in] Privileges
* The privileges for the token.
*
* @param[in] Owner
* The main user (or also owner) that represents the token that we create.
*
* @param[in] PrimaryGroup
* The main group that represents the token that we create.
*
* @param[in] DefaultDacl
* A discretionary access control list for the token.
*
* @param[in] TokenSource
* Source (or the origin) of the access token that creates it.
*
* @param[in] SystemToken
* If set to TRUE, the newly created token is a system token and only in charge
* by the internal system. The function directly returns a pointer to the
* created token object for system kernel use. Otherwise if set to FALSE, the
* function inserts the object to a handle making it a regular access token.
*
* @return
* Returns STATUS_SUCCESS if token creation has completed successfully.
* STATUS_INSUFFICIENT_RESOURCES is returned if the dynamic area of memory of the
* token hasn't been allocated because of lack of memory resources. A failure
* NTSTATUS code is returned otherwise.
*/
NTSTATUS
NTAPI
SepCreateToken(
_Out_ PHANDLE TokenHandle,
_In_ KPROCESSOR_MODE PreviousMode,
_In_ ACCESS_MASK DesiredAccess,
_In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
_In_ TOKEN_TYPE TokenType,
_In_ SECURITY_IMPERSONATION_LEVEL ImpersonationLevel,
_In_ PLUID AuthenticationId,
_In_ PLARGE_INTEGER ExpirationTime,
_In_ PSID_AND_ATTRIBUTES User,
_In_ ULONG GroupCount,
_In_ PSID_AND_ATTRIBUTES Groups,
_In_ ULONG GroupsLength,
_In_ ULONG PrivilegeCount,
_In_ PLUID_AND_ATTRIBUTES Privileges,
_In_opt_ PSID Owner,
_In_ PSID PrimaryGroup,
_In_opt_ PACL DefaultDacl,
_In_ PTOKEN_SOURCE TokenSource,
_In_ BOOLEAN SystemToken)
{
NTSTATUS Status;
PTOKEN AccessToken;
ULONG TokenFlags = 0;
ULONG PrimaryGroupIndex, DefaultOwnerIndex;
LUID TokenId;
LUID ModifiedId;
PVOID EndMem;
ULONG PrivilegesLength;
ULONG UserGroupsLength;
ULONG VariableLength;
ULONG DynamicPartSize, TotalSize;
ULONG TokenPagedCharges;
ULONG i;
PAGED_CODE();
/* Loop all groups */
for (i = 0; i < GroupCount; i++)
{
/* Check for mandatory groups */
if (Groups[i].Attributes & SE_GROUP_MANDATORY)
{
/* Force them to be enabled */
Groups[i].Attributes |= (SE_GROUP_ENABLED | SE_GROUP_ENABLED_BY_DEFAULT);
}
/* Check of the group is an admin group */
if (RtlEqualSid(SeAliasAdminsSid, Groups[i].Sid))
{
/* Remember this so we can optimize queries later */
TokenFlags |= TOKEN_HAS_ADMIN_GROUP;
}
}
/* Allocate unique IDs for the token */
ExAllocateLocallyUniqueId(&TokenId);
ExAllocateLocallyUniqueId(&ModifiedId);
/* Compute how much size we need to allocate for the token */
/* Privileges size */
PrivilegesLength = PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES);
PrivilegesLength = ALIGN_UP_BY(PrivilegesLength, sizeof(PVOID));
/* User and groups size */
UserGroupsLength = (1 + GroupCount) * sizeof(SID_AND_ATTRIBUTES);
UserGroupsLength += RtlLengthSid(User->Sid);
for (i = 0; i < GroupCount; i++)
{
UserGroupsLength += RtlLengthSid(Groups[i].Sid);
}
UserGroupsLength = ALIGN_UP_BY(UserGroupsLength, sizeof(PVOID));
/* Add the additional groups array length */
UserGroupsLength += ALIGN_UP_BY(GroupsLength, sizeof(PVOID));
VariableLength = PrivilegesLength + UserGroupsLength;
TotalSize = FIELD_OFFSET(TOKEN, VariablePart) + VariableLength;
/*
* A token is considered slim if it has the default dynamic
* contents, or in other words, the primary group and ACL.
* We judge if such contents are default by checking their
* total size if it's over the range. On Windows this range
* is 0x1F4 (aka 500). If the size of the whole dynamic contents
* is over that range then the token is considered fat and
* the token will be charged the whole of its token body length
* plus the dynamic size.
*/
DynamicPartSize = DefaultDacl ? DefaultDacl->AclSize : 0;
DynamicPartSize += RtlLengthSid(PrimaryGroup);
if (DynamicPartSize > SE_TOKEN_DYNAMIC_SLIM)
{
TokenPagedCharges = DynamicPartSize + TotalSize;
}
else
{
TokenPagedCharges = SE_TOKEN_DYNAMIC_SLIM + TotalSize;
}
Status = ObCreateObject(PreviousMode,
SeTokenObjectType,
ObjectAttributes,
PreviousMode,
NULL,
TotalSize,
TokenPagedCharges,
0,
(PVOID*)&AccessToken);
if (!NT_SUCCESS(Status))
{
DPRINT1("ObCreateObject() failed (Status 0x%lx)\n", Status);
return Status;
}
/* Zero out the buffer and initialize the token */
RtlZeroMemory(AccessToken, TotalSize);
AccessToken->TokenId = TokenId;
AccessToken->TokenType = TokenType;
AccessToken->ImpersonationLevel = ImpersonationLevel;
/* Initialise the lock for the access token */
Status = SepCreateTokenLock(AccessToken);
if (!NT_SUCCESS(Status))
goto Quit;
AccessToken->TokenSource.SourceIdentifier = TokenSource->SourceIdentifier;
RtlCopyMemory(AccessToken->TokenSource.SourceName,
TokenSource->SourceName,
sizeof(TokenSource->SourceName));
AccessToken->ExpirationTime = *ExpirationTime;
AccessToken->ModifiedId = ModifiedId;
AccessToken->DynamicCharged = TokenPagedCharges - TotalSize;
AccessToken->TokenFlags = TokenFlags & ~TOKEN_SESSION_NOT_REFERENCED;
/* Copy and reference the logon session */
AccessToken->AuthenticationId = *AuthenticationId;
Status = SepRmReferenceLogonSession(&AccessToken->AuthenticationId);
if (!NT_SUCCESS(Status))
{
/* No logon session could be found, bail out */
DPRINT1("SepRmReferenceLogonSession() failed (Status 0x%lx)\n", Status);
/* Set the flag for proper cleanup by the delete procedure */
AccessToken->TokenFlags |= TOKEN_SESSION_NOT_REFERENCED;
goto Quit;
}
/* Insert the referenced logon session into the token */
Status = SepRmInsertLogonSessionIntoToken(AccessToken);
if (!NT_SUCCESS(Status))
{
/* Failed to insert the logon session into the token, bail out */
DPRINT1("SepRmInsertLogonSessionIntoToken() failed (Status 0x%lx)\n", Status);
goto Quit;
}
/* Fill in token debug information */
#if DBG
/*
* We must determine ourselves that the current
* process is not the initial CPU one. The initial
* process is not a "real" process, that is, the
* Process Manager has not yet been initialized and
* as a matter of fact we are creating a token before
* any process gets created by Ps. If it turns out
* that the current process is the initial CPU process
* where token creation execution takes place, don't
* do anything.
*/
if (PsGetCurrentProcess() != &KiInitialProcess)
{
RtlCopyMemory(AccessToken->ImageFileName,
PsGetCurrentProcess()->ImageFileName,
min(sizeof(AccessToken->ImageFileName), sizeof(PsGetCurrentProcess()->ImageFileName)));
AccessToken->ProcessCid = PsGetCurrentProcessId();
AccessToken->ThreadCid = PsGetCurrentThreadId();
}
AccessToken->CreateMethod = TOKEN_CREATE_METHOD;
#endif
/* Assign the data that reside in the token's variable information area */
AccessToken->VariableLength = VariableLength;
EndMem = (PVOID)&AccessToken->VariablePart;
/* Copy the privileges */
AccessToken->PrivilegeCount = PrivilegeCount;
AccessToken->Privileges = NULL;
if (PrivilegeCount > 0)
{
AccessToken->Privileges = EndMem;
EndMem = (PVOID)((ULONG_PTR)EndMem + PrivilegesLength);
VariableLength -= PrivilegesLength;
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
RtlCopyMemory(AccessToken->Privileges,
Privileges,
PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES));
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
}
else
{
RtlCopyMemory(AccessToken->Privileges,
Privileges,
PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES));
}
if (!NT_SUCCESS(Status))
goto Quit;
}
/* Update the privilege flags */
SepUpdatePrivilegeFlagsToken(AccessToken);
/* Copy the user and groups */
AccessToken->UserAndGroupCount = 1 + GroupCount;
AccessToken->UserAndGroups = EndMem;
EndMem = &AccessToken->UserAndGroups[AccessToken->UserAndGroupCount];
VariableLength -= ((ULONG_PTR)EndMem - (ULONG_PTR)AccessToken->UserAndGroups);
Status = RtlCopySidAndAttributesArray(1,
User,
VariableLength,
&AccessToken->UserAndGroups[0],
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
goto Quit;
Status = RtlCopySidAndAttributesArray(GroupCount,
Groups,
VariableLength,
&AccessToken->UserAndGroups[1],
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
goto Quit;
/* Find the token primary group and default owner */
Status = SepFindPrimaryGroupAndDefaultOwner(AccessToken,
PrimaryGroup,
Owner,
&PrimaryGroupIndex,
&DefaultOwnerIndex);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepFindPrimaryGroupAndDefaultOwner failed (Status 0x%lx)\n", Status);
goto Quit;
}
/*
* Now allocate the token's dynamic information area
* and set the data. The dynamic part consists of two
* contents, the primary group SID and the default DACL
* of the token, in this strict order.
*/
AccessToken->DynamicPart = ExAllocatePoolWithTag(PagedPool,
DynamicPartSize,
TAG_TOKEN_DYNAMIC);
if (AccessToken->DynamicPart == NULL)
{
Status = STATUS_INSUFFICIENT_RESOURCES;
goto Quit;
}
/* Unused memory in the dynamic area */
AccessToken->DynamicAvailable = 0;
/*
* Assign the primary group to the token
* and put it in the dynamic part as well.
*/
EndMem = (PVOID)AccessToken->DynamicPart;
AccessToken->PrimaryGroup = EndMem;
RtlCopySid(RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid),
EndMem,
AccessToken->UserAndGroups[PrimaryGroupIndex].Sid);
AccessToken->DefaultOwnerIndex = DefaultOwnerIndex;
EndMem = (PVOID)((ULONG_PTR)EndMem + RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid));
/*
* We have assigned a primary group and put it in the
* dynamic part, now it's time to copy the provided
* default DACL (if it's provided to begin with) into
* the DACL field of the token and put it at the end
* tail of the dynamic part too.
*/
if (DefaultDacl != NULL)
{
AccessToken->DefaultDacl = EndMem;
RtlCopyMemory(EndMem,
DefaultDacl,
DefaultDacl->AclSize);
}
/* Insert the token only if it's not the system token, otherwise return it directly */
if (!SystemToken)
{
Status = ObInsertObject(AccessToken,
NULL,
DesiredAccess,
0,
NULL,
TokenHandle);
if (!NT_SUCCESS(Status))
{
DPRINT1("ObInsertObject() failed (Status 0x%lx)\n", Status);
}
}
else
{
/* Return pointer instead of handle */
*TokenHandle = (HANDLE)AccessToken;
}
Quit:
if (!NT_SUCCESS(Status))
{
/* Dereference the token, the delete procedure will clean it up */
ObDereferenceObject(AccessToken);
}
return Status;
}
/**
* @brief
* Duplicates an access token, from an existing valid token.
*
* @param[in] Token
* Access token to duplicate.
*
* @param[in] ObjectAttributes
* Object attributes for the new token.
*
* @param[in] EffectiveOnly
* If set to TRUE, the function removes all the disabled privileges and groups of the token
* to duplicate.
*
* @param[in] TokenType
* Type of token.
*
* @param[in] Level
* Security impersonation level of a token.
*
* @param[in] PreviousMode
* The processor request level mode.
*
* @param[out] NewAccessToken
* The duplicated token.
*
* @return
* Returns STATUS_SUCCESS if the token has been duplicated. STATUS_INSUFFICIENT_RESOURCES is returned
* if memory pool allocation of the dynamic part of the token for duplication has failed due to the lack
* of memory resources. A failure NTSTATUS code is returned otherwise.
*/
NTSTATUS
NTAPI
SepDuplicateToken(
_In_ PTOKEN Token,
_In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
_In_ BOOLEAN EffectiveOnly,
_In_ TOKEN_TYPE TokenType,
_In_ SECURITY_IMPERSONATION_LEVEL Level,
_In_ KPROCESSOR_MODE PreviousMode,
_Out_ PTOKEN* NewAccessToken)
{
NTSTATUS Status;
PTOKEN AccessToken;
PVOID EndMem;
ULONG PrimaryGroupIndex;
ULONG VariableLength;
ULONG DynamicPartSize, TotalSize;
ULONG PrivilegesIndex, GroupsIndex;
PAGED_CODE();
/* Compute how much size we need to allocate for the token */
VariableLength = Token->VariableLength;
TotalSize = FIELD_OFFSET(TOKEN, VariablePart) + VariableLength;
/*
* Compute how much size we need to allocate
* the dynamic part of the newly duplicated
* token.
*/
DynamicPartSize = Token->DefaultDacl ? Token->DefaultDacl->AclSize : 0;
DynamicPartSize += RtlLengthSid(Token->PrimaryGroup);
Status = ObCreateObject(PreviousMode,
SeTokenObjectType,
ObjectAttributes,
PreviousMode,
NULL,
TotalSize,
Token->DynamicCharged,
TotalSize,
(PVOID*)&AccessToken);
if (!NT_SUCCESS(Status))
{
DPRINT1("ObCreateObject() failed (Status 0x%lx)\n", Status);
return Status;
}
/* Zero out the buffer and initialize the token */
RtlZeroMemory(AccessToken, TotalSize);
ExAllocateLocallyUniqueId(&AccessToken->TokenId);
AccessToken->TokenType = TokenType;
AccessToken->ImpersonationLevel = Level;
/* Initialise the lock for the access token */
Status = SepCreateTokenLock(AccessToken);
if (!NT_SUCCESS(Status))
{
ObDereferenceObject(AccessToken);
return Status;
}
/* Copy the immutable fields */
AccessToken->TokenSource.SourceIdentifier = Token->TokenSource.SourceIdentifier;
RtlCopyMemory(AccessToken->TokenSource.SourceName,
Token->TokenSource.SourceName,
sizeof(Token->TokenSource.SourceName));
AccessToken->AuthenticationId = Token->AuthenticationId;
AccessToken->ParentTokenId = Token->ParentTokenId;
AccessToken->ExpirationTime = Token->ExpirationTime;
AccessToken->OriginatingLogonSession = Token->OriginatingLogonSession;
AccessToken->DynamicCharged = Token->DynamicCharged;
/* Lock the source token and copy the mutable fields */
SepAcquireTokenLockShared(Token);
AccessToken->SessionId = Token->SessionId;
AccessToken->ModifiedId = Token->ModifiedId;
AccessToken->TokenFlags = Token->TokenFlags & ~TOKEN_SESSION_NOT_REFERENCED;
/* Reference the logon session */
Status = SepRmReferenceLogonSession(&AccessToken->AuthenticationId);
if (!NT_SUCCESS(Status))
{
/* No logon session could be found, bail out */
DPRINT1("SepRmReferenceLogonSession() failed (Status 0x%lx)\n", Status);
/* Set the flag for proper cleanup by the delete procedure */
AccessToken->TokenFlags |= TOKEN_SESSION_NOT_REFERENCED;
goto Quit;
}
/* Insert the referenced logon session into the token */
Status = SepRmInsertLogonSessionIntoToken(AccessToken);
if (!NT_SUCCESS(Status))
{
/* Failed to insert the logon session into the token, bail out */
DPRINT1("SepRmInsertLogonSessionIntoToken() failed (Status 0x%lx)\n", Status);
goto Quit;
}
/* Fill in token debug information */
#if DBG
RtlCopyMemory(AccessToken->ImageFileName,
PsGetCurrentProcess()->ImageFileName,
min(sizeof(AccessToken->ImageFileName), sizeof(PsGetCurrentProcess()->ImageFileName)));
AccessToken->ProcessCid = PsGetCurrentProcessId();
AccessToken->ThreadCid = PsGetCurrentThreadId();
AccessToken->CreateMethod = TOKEN_DUPLICATE_METHOD;
#endif
/* Assign the data that reside in the token's variable information area */
AccessToken->VariableLength = VariableLength;
EndMem = (PVOID)&AccessToken->VariablePart;
/* Copy the privileges */
AccessToken->PrivilegeCount = 0;
AccessToken->Privileges = NULL;
if (Token->Privileges && (Token->PrivilegeCount > 0))
{
ULONG PrivilegesLength = Token->PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES);
PrivilegesLength = ALIGN_UP_BY(PrivilegesLength, sizeof(PVOID));
ASSERT(VariableLength >= PrivilegesLength);
AccessToken->PrivilegeCount = Token->PrivilegeCount;
AccessToken->Privileges = EndMem;
EndMem = (PVOID)((ULONG_PTR)EndMem + PrivilegesLength);
VariableLength -= PrivilegesLength;
RtlCopyMemory(AccessToken->Privileges,
Token->Privileges,
AccessToken->PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES));
}
/* Copy the user and groups */
AccessToken->UserAndGroupCount = 0;
AccessToken->UserAndGroups = NULL;
if (Token->UserAndGroups && (Token->UserAndGroupCount > 0))
{
AccessToken->UserAndGroupCount = Token->UserAndGroupCount;
AccessToken->UserAndGroups = EndMem;
EndMem = &AccessToken->UserAndGroups[AccessToken->UserAndGroupCount];
VariableLength -= ((ULONG_PTR)EndMem - (ULONG_PTR)AccessToken->UserAndGroups);
Status = RtlCopySidAndAttributesArray(AccessToken->UserAndGroupCount,
Token->UserAndGroups,
VariableLength,
AccessToken->UserAndGroups,
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("RtlCopySidAndAttributesArray(UserAndGroups) failed (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Find the token primary group */
Status = SepFindPrimaryGroupAndDefaultOwner(AccessToken,
Token->PrimaryGroup,
NULL,
&PrimaryGroupIndex,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepFindPrimaryGroupAndDefaultOwner failed (Status 0x%lx)\n", Status);
goto Quit;
}
/* Copy the restricted SIDs */
AccessToken->RestrictedSidCount = 0;
AccessToken->RestrictedSids = NULL;
if (Token->RestrictedSids && (Token->RestrictedSidCount > 0))
{
AccessToken->RestrictedSidCount = Token->RestrictedSidCount;
AccessToken->RestrictedSids = EndMem;
EndMem = &AccessToken->RestrictedSids[AccessToken->RestrictedSidCount];
VariableLength -= ((ULONG_PTR)EndMem - (ULONG_PTR)AccessToken->RestrictedSids);
Status = RtlCopySidAndAttributesArray(AccessToken->RestrictedSidCount,
Token->RestrictedSids,
VariableLength,
AccessToken->RestrictedSids,
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("RtlCopySidAndAttributesArray(RestrictedSids) failed (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Now allocate the token's dynamic information area and set the data */
AccessToken->DynamicPart = ExAllocatePoolWithTag(PagedPool,
DynamicPartSize,
TAG_TOKEN_DYNAMIC);
if (AccessToken->DynamicPart == NULL)
{
Status = STATUS_INSUFFICIENT_RESOURCES;
goto Quit;
}
/* Unused memory in the dynamic area */
AccessToken->DynamicAvailable = 0;
/*
* Assign the primary group to the token
* and put it in the dynamic part as well.
*/
EndMem = (PVOID)AccessToken->DynamicPart;
AccessToken->PrimaryGroup = EndMem;
RtlCopySid(RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid),
EndMem,
AccessToken->UserAndGroups[PrimaryGroupIndex].Sid);
AccessToken->DefaultOwnerIndex = Token->DefaultOwnerIndex;
EndMem = (PVOID)((ULONG_PTR)EndMem + RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid));
/*
* The existing token has a default DACL only
* if it has an allocated dynamic part.
*/
if (Token->DynamicPart && Token->DefaultDacl)
{
AccessToken->DefaultDacl = EndMem;
RtlCopyMemory(EndMem,
Token->DefaultDacl,
Token->DefaultDacl->AclSize);
}
/*
* Filter the token by removing the disabled privileges
* and groups if the caller wants to duplicate an access
* token as effective only.
*/
if (EffectiveOnly)
{
/*
* Begin querying the groups and search for disabled ones. Do not touch the
* user which is at the first position because it cannot be disabled, no
* matter what attributes it has.
*/
for (GroupsIndex = 1; GroupsIndex < AccessToken->UserAndGroupCount; GroupsIndex++)
{
/*
* A group is considered disabled if its attributes is either
* 0 or SE_GROUP_ENABLED is not included in the attributes flags list.
* That is because a certain user and/or group can have several attributes
* that bear no influence on whether a user/group is enabled or not
* (SE_GROUP_ENABLED_BY_DEFAULT for example which is a mere indicator
* that the group has just been enabled by default). A mandatory
* group (that is, the group has SE_GROUP_MANDATORY attribute)
* by standards it's always enabled and no one can disable it.
*/
if (AccessToken->UserAndGroups[GroupsIndex].Attributes == 0 ||
(AccessToken->UserAndGroups[GroupsIndex].Attributes & SE_GROUP_ENABLED) == 0)
{
/*
* If this group is an administrators group
* and the token belongs to such group,
* we've to take away TOKEN_HAS_ADMIN_GROUP
* for the fact that's not enabled and as
* such the token no longer belongs to
* this group.
*/
if (RtlEqualSid(SeAliasAdminsSid,
&AccessToken->UserAndGroups[GroupsIndex].Sid))
{
AccessToken->TokenFlags &= ~TOKEN_HAS_ADMIN_GROUP;
}
/*
* A group is not enabled, it's time to remove
* from the token and update the groups index
* accordingly and continue with the next group.
*/
SepRemoveUserGroupToken(AccessToken, GroupsIndex);
GroupsIndex--;
}
}
/* Begin querying the privileges and search for disabled ones */
for (PrivilegesIndex = 0; PrivilegesIndex < AccessToken->PrivilegeCount; PrivilegesIndex++)
{
/*
* A privilege is considered disabled if its attributes is either
* 0 or SE_PRIVILEGE_ENABLED is not included in the attributes flags list.
* That is because a certain privilege can have several attributes
* that bear no influence on whether a privilege is enabled or not
* (SE_PRIVILEGE_ENABLED_BY_DEFAULT for example which is a mere indicator
* that the privilege has just been enabled by default).
*/
if (AccessToken->Privileges[PrivilegesIndex].Attributes == 0 ||
(AccessToken->Privileges[PrivilegesIndex].Attributes & SE_PRIVILEGE_ENABLED) == 0)
{
/*
* A privilege is not enabled, therefor it's time
* to strip it from the token and continue with the next
* privilege. Of course we must also want to update the
* privileges index accordingly.
*/
SepRemovePrivilegeToken(AccessToken, PrivilegesIndex);
PrivilegesIndex--;
}
}
}
/* Return the token to the caller */
*NewAccessToken = AccessToken;
Status = STATUS_SUCCESS;
Quit:
if (!NT_SUCCESS(Status))
{
/* Dereference the token, the delete procedure will clean it up */
ObDereferenceObject(AccessToken);
}
/* Unlock the source token */
SepReleaseTokenLock(Token);
return Status;
}
/**
* @brief
* Private helper function responsible for creating a restricted access
* token, that is, a filtered token from privileges and groups and with
* restricted SIDs added into the token on demand by the caller.
*
* @param[in] Token
* An existing and valid access token.
*
* @param[in] PrivilegesToBeDeleted
* A list of privileges to be deleted within the token that's going
* to be filtered. This parameter is ignored if the caller wants to disable
* all the privileges by specifying DISABLE_MAX_PRIVILEGE in the flags
* parameter.
*
* @param[in] SidsToBeDisabled
* A list of group SIDs to be disabled within the token. This parameter
* can be NULL.
*
* @param[in] RestrictedSidsIntoToken
* A list of restricted SIDs to be added into the token. This parameter
* can be NULL.
*
* @param[in] PrivilegesCount
* The privilege count of the privileges list.
*
* @param[in] RegularGroupsSidCount
* The SIDs count of the group SIDs list.
*
* @param[in] RestrictedSidsCount
* The restricted SIDs count of restricted SIDs list.
*
* @param[in] PrivilegeFlags
* Influences how the privileges should be filtered in an access
* token. See NtFilterToken syscall for more information.
*
* @param[in] PreviousMode
* Processor level access mode.
*
* @param[out] FilteredToken
* The filtered token, returned to the caller.
*
* @return
* Returns STATUS_SUCCESS if token token filtering has completed successfully.
* STATUS_INVALID_PARAMETER is returned if one or more of the parameters
* do not meet the conditions imposed by the function. A failure NTSTATUS
* code is returned otherwise.
*
* @remarks
* The final outcome of privileges and/or SIDs filtering is not always
* deterministic. That is, any privileges or SIDs that aren't present
* in the access token are ignored and the function continues with the
* next privilege or SID to find for filtering. For a fully deterministic
* outcome the caller is responsible for querying the information details
* of privileges and SIDs present in the token and then afterwards use
* such obtained information to do any kind of filtering to the token.
*/
static
NTSTATUS
SepPerformTokenFiltering(
_In_ PTOKEN Token,
_In_opt_ PLUID_AND_ATTRIBUTES PrivilegesToBeDeleted,
_In_opt_ PSID_AND_ATTRIBUTES SidsToBeDisabled,
_In_opt_ PSID_AND_ATTRIBUTES RestrictedSidsIntoToken,
_When_(PrivilegesToBeDeleted != NULL, _In_) ULONG PrivilegesCount,
_When_(SidsToBeDisabled != NULL, _In_) ULONG RegularGroupsSidCount,
_When_(RestrictedSidsIntoToken != NULL, _In_) ULONG RestrictedSidsCount,
_In_ ULONG PrivilegeFlags,
_In_ KPROCESSOR_MODE PreviousMode,
_Out_ PTOKEN *FilteredToken)
{
NTSTATUS Status;
PTOKEN AccessToken;
PVOID EndMem;
ULONG DynamicPartSize;
ULONG RestrictedSidsLength;
ULONG PrivilegesLength;
ULONG PrimaryGroupIndex;
ULONG RestrictedSidsInList;
ULONG RestrictedSidsInToken;
ULONG VariableLength, TotalSize;
ULONG PrivsInToken, PrivsInList;
ULONG GroupsInToken, GroupsInList;
BOOLEAN WantPrivilegesDisabled;
BOOLEAN FoundPrivilege;
BOOLEAN FoundGroup;
PAGED_CODE();
/* Ensure that the source token is valid, and lock it */
ASSERT(Token);
SepAcquireTokenLockShared(Token);
/* Assume the caller doesn't want privileges disabled */
WantPrivilegesDisabled = FALSE;
/* Assume we haven't found anything */
FoundPrivilege = FALSE;
FoundGroup = FALSE;
/*
* Take the size that we need for filtered token
* allocation based upon the existing access token
* we've been given.
*/
VariableLength = Token->VariableLength;
if (RestrictedSidsIntoToken != NULL)
{
/*
* If the caller provided a list of restricted SIDs
* to be added onto the filtered access token then
* we must compute the size which is the total space
* of the current token and the length of the restricted
* SIDs for the filtered token.
*/
RestrictedSidsLength = RestrictedSidsCount * sizeof(SID_AND_ATTRIBUTES);
RestrictedSidsLength += RtlLengthSidAndAttributes(RestrictedSidsCount, RestrictedSidsIntoToken);
RestrictedSidsLength = ALIGN_UP_BY(RestrictedSidsLength, sizeof(PVOID));
/*
* The variable length of the token is not just
* the actual space length of the existing token
* but also the sum of the restricted SIDs length.
*/
VariableLength += RestrictedSidsLength;
TotalSize = FIELD_OFFSET(TOKEN, VariablePart) + VariableLength + RestrictedSidsLength;
}
else
{
/* Otherwise the size is of the actual current token */
TotalSize = FIELD_OFFSET(TOKEN, VariablePart) + VariableLength;
}
/*
* Compute how much size we need to allocate
* the dynamic part of the newly duplicated
* token.
*/
DynamicPartSize = Token->DefaultDacl ? Token->DefaultDacl->AclSize : 0;
DynamicPartSize += RtlLengthSid(Token->PrimaryGroup);
/* Set up a filtered token object */
Status = ObCreateObject(PreviousMode,
SeTokenObjectType,
NULL,
PreviousMode,
NULL,
TotalSize,
Token->DynamicCharged,
TotalSize,
(PVOID*)&AccessToken);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepPerformTokenFiltering(): Failed to create the filtered token object (Status 0x%lx)\n", Status);
/* Unlock the source token and bail out */
SepReleaseTokenLock(Token);
return Status;
}
/* Initialize the token and begin filling stuff to it */
RtlZeroMemory(AccessToken, TotalSize);
/* Set up a lock for the new token */
Status = SepCreateTokenLock(AccessToken);
if (!NT_SUCCESS(Status))
goto Quit;
/* Allocate new IDs for the token */
ExAllocateLocallyUniqueId(&AccessToken->TokenId);
ExAllocateLocallyUniqueId(&AccessToken->ModifiedId);
/* Copy the type and impersonation level from the token */
AccessToken->TokenType = Token->TokenType;
AccessToken->ImpersonationLevel = Token->ImpersonationLevel;
/* Copy the immutable fields */
AccessToken->TokenSource.SourceIdentifier = Token->TokenSource.SourceIdentifier;
RtlCopyMemory(AccessToken->TokenSource.SourceName,
Token->TokenSource.SourceName,
sizeof(Token->TokenSource.SourceName));
AccessToken->AuthenticationId = Token->AuthenticationId;
AccessToken->ParentTokenId = Token->TokenId;
AccessToken->OriginatingLogonSession = Token->OriginatingLogonSession;
AccessToken->DynamicCharged = Token->DynamicCharged;
AccessToken->ExpirationTime = Token->ExpirationTime;
/* Copy the mutable fields */
AccessToken->SessionId = Token->SessionId;
AccessToken->TokenFlags = Token->TokenFlags & ~TOKEN_SESSION_NOT_REFERENCED;
/* Reference the logon session */
Status = SepRmReferenceLogonSession(&AccessToken->AuthenticationId);
if (!NT_SUCCESS(Status))
{
/* We failed, bail out*/
DPRINT1("SepPerformTokenFiltering(): Failed to reference the logon session (Status 0x%lx)\n", Status);
AccessToken->TokenFlags |= TOKEN_SESSION_NOT_REFERENCED;
goto Quit;
}
/* Insert the referenced logon session into the token */
Status = SepRmInsertLogonSessionIntoToken(AccessToken);
if (!NT_SUCCESS(Status))
{
/* Failed to insert the logon session into the token, bail out */
DPRINT1("SepPerformTokenFiltering(): Failed to insert the logon session into token (Status 0x%lx)\n", Status);
goto Quit;
}
/* Fill in token debug information */
#if DBG
RtlCopyMemory(AccessToken->ImageFileName,
PsGetCurrentProcess()->ImageFileName,
min(sizeof(AccessToken->ImageFileName), sizeof(PsGetCurrentProcess()->ImageFileName)));
AccessToken->ProcessCid = PsGetCurrentProcessId();
AccessToken->ThreadCid = PsGetCurrentThreadId();
AccessToken->CreateMethod = TOKEN_FILTER_METHOD;
#endif
/* Assign the data that reside in the token's variable information area */
AccessToken->VariableLength = VariableLength;
EndMem = (PVOID)&AccessToken->VariablePart;
/* Copy the privileges from the existing token */
AccessToken->PrivilegeCount = 0;
AccessToken->Privileges = NULL;
if (Token->Privileges && (Token->PrivilegeCount > 0))
{
PrivilegesLength = Token->PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES);
PrivilegesLength = ALIGN_UP_BY(PrivilegesLength, sizeof(PVOID));
/*
* Ensure that the token can actually hold all
* the privileges from the existing token.
* Otherwise something's seriously wrong and
* we've to guard ourselves.
*/
ASSERT(VariableLength >= PrivilegesLength);
AccessToken->PrivilegeCount = Token->PrivilegeCount;
AccessToken->Privileges = EndMem;
EndMem = (PVOID)((ULONG_PTR)EndMem + PrivilegesLength);
VariableLength -= PrivilegesLength;
RtlCopyMemory(AccessToken->Privileges,
Token->Privileges,
AccessToken->PrivilegeCount * sizeof(LUID_AND_ATTRIBUTES));
}
/* Copy the user and groups */
AccessToken->UserAndGroupCount = 0;
AccessToken->UserAndGroups = NULL;
if (Token->UserAndGroups && (Token->UserAndGroupCount > 0))
{
AccessToken->UserAndGroupCount = Token->UserAndGroupCount;
AccessToken->UserAndGroups = EndMem;
EndMem = &AccessToken->UserAndGroups[AccessToken->UserAndGroupCount];
VariableLength -= ((ULONG_PTR)EndMem - (ULONG_PTR)AccessToken->UserAndGroups);
Status = RtlCopySidAndAttributesArray(AccessToken->UserAndGroupCount,
Token->UserAndGroups,
VariableLength,
AccessToken->UserAndGroups,
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepPerformTokenFiltering(): Failed to copy the groups into token (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Copy the restricted SIDs */
AccessToken->RestrictedSidCount = 0;
AccessToken->RestrictedSids = NULL;
if (Token->RestrictedSids && (Token->RestrictedSidCount > 0))
{
AccessToken->RestrictedSidCount = Token->RestrictedSidCount;
AccessToken->RestrictedSids = EndMem;
EndMem = &AccessToken->RestrictedSids[AccessToken->RestrictedSidCount];
VariableLength -= ((ULONG_PTR)EndMem - (ULONG_PTR)AccessToken->RestrictedSids);
Status = RtlCopySidAndAttributesArray(AccessToken->RestrictedSidCount,
Token->RestrictedSids,
VariableLength,
AccessToken->RestrictedSids,
EndMem,
&EndMem,
&VariableLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepPerformTokenFiltering(): Failed to copy the restricted SIDs into token (Status 0x%lx)\n", Status);
goto Quit;
}
}
/*
* Insert the restricted SIDs into the token on
* the request by the caller.
*/
if (RestrictedSidsIntoToken != NULL)
{
for (RestrictedSidsInList = 0; RestrictedSidsInList < RestrictedSidsCount; RestrictedSidsInList++)
{
/* Did the caller assign attributes to the restricted SIDs? */
if (RestrictedSidsIntoToken[RestrictedSidsInList].Attributes != 0)
{
/* There mustn't be any attributes, bail out */
DPRINT1("SepPerformTokenFiltering(): There mustn't be any attributes to restricted SIDs!\n");
Status = STATUS_INVALID_PARAMETER;
goto Quit;
}
}
/*
* Ensure that the token can hold the restricted SIDs
* (the variable length is calculated at the beginning
* of the routine call).
*/
ASSERT(VariableLength >= RestrictedSidsLength);
/*
* Now let's begin inserting the restricted SIDs into the filtered
* access token from the list the caller gave us.
*/
AccessToken->RestrictedSidCount = RestrictedSidsCount;
AccessToken->RestrictedSids = EndMem;
EndMem = (PVOID)((ULONG_PTR)EndMem + RestrictedSidsLength);
VariableLength -= RestrictedSidsLength;
RtlCopyMemory(AccessToken->RestrictedSids,
RestrictedSidsIntoToken,
AccessToken->RestrictedSidCount * sizeof(SID_AND_ATTRIBUTES));
/*
* As we've copied the restricted SIDs into
* the token, we must assign them the following
* combination of attributes SE_GROUP_ENABLED,
* SE_GROUP_ENABLED_BY_DEFAULT and SE_GROUP_MANDATORY.
* With such attributes we estabilish that restricting
* SIDs into the token are enabled for access checks.
*/
for (RestrictedSidsInToken = 0; RestrictedSidsInToken < AccessToken->RestrictedSidCount; RestrictedSidsInToken++)
{
AccessToken->RestrictedSids[RestrictedSidsInToken].Attributes |= (SE_GROUP_ENABLED | SE_GROUP_ENABLED_BY_DEFAULT | SE_GROUP_MANDATORY);
}
/*
* As we added restricted SIDs into the token, mark
* it as restricted.
*/
AccessToken->TokenFlags |= TOKEN_IS_RESTRICTED;
}
/* Search for the primary group */
Status = SepFindPrimaryGroupAndDefaultOwner(AccessToken,
Token->PrimaryGroup,
NULL,
&PrimaryGroupIndex,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT1("SepPerformTokenFiltering(): Failed searching for the primary group (Status 0x%lx)\n", Status);
goto Quit;
}
/* Now allocate the token's dynamic information area and set the data */
AccessToken->DynamicPart = ExAllocatePoolWithTag(PagedPool,
DynamicPartSize,
TAG_TOKEN_DYNAMIC);
if (AccessToken->DynamicPart == NULL)
{
Status = STATUS_INSUFFICIENT_RESOURCES;
goto Quit;
}
/* Unused memory in the dynamic area */
AccessToken->DynamicAvailable = 0;
/*
* Assign the primary group to the token
* and put it in the dynamic part as well.
*/
EndMem = (PVOID)AccessToken->DynamicPart;
AccessToken->PrimaryGroup = EndMem;
RtlCopySid(RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid),
EndMem,
AccessToken->UserAndGroups[PrimaryGroupIndex].Sid);
AccessToken->DefaultOwnerIndex = Token->DefaultOwnerIndex;
EndMem = (PVOID)((ULONG_PTR)EndMem + RtlLengthSid(AccessToken->UserAndGroups[PrimaryGroupIndex].Sid));
/*
* The existing token has a default DACL only
* if it has an allocated dynamic part.
*/
if (Token->DynamicPart && Token->DefaultDacl)
{
AccessToken->DefaultDacl = EndMem;
RtlCopyMemory(EndMem,
Token->DefaultDacl,
Token->DefaultDacl->AclSize);
}
/*
* Now figure out what does the caller
* want with the privileges.
*/
if (PrivilegeFlags & DISABLE_MAX_PRIVILEGE)
{
/*
* The caller wants them disabled, cache this request
* for later operations.
*/
WantPrivilegesDisabled = TRUE;
}
if (PrivilegeFlags & SANDBOX_INERT)
{
/* The caller wants an inert token, store the TOKEN_SANDBOX_INERT flag now */
AccessToken->TokenFlags |= TOKEN_SANDBOX_INERT;
}
/*
* Now it's time to filter the token's privileges.
* Loop all the privileges in the token.
*/
for (PrivsInToken = 0; PrivsInToken < AccessToken->PrivilegeCount; PrivsInToken++)
{
if (WantPrivilegesDisabled)
{
/*
* We got the acknowledgement that the caller wants
* to disable all the privileges so let's just do it.
* However, as per the general documentation is stated
* that only SE_CHANGE_NOTIFY_PRIVILEGE must be kept
* therefore in that case we must skip this privilege.
*/
if (AccessToken->Privileges[PrivsInToken].Luid.LowPart == SE_CHANGE_NOTIFY_PRIVILEGE)
{
continue;
}
else
{
/*
* The act of disabling privileges actually means
* "deleting" them from the access token entirely.
* First we must disable them so that we can update
* token flags accordingly.
*/
AccessToken->Privileges[PrivsInToken].Attributes &= ~SE_PRIVILEGE_ENABLED;
SepUpdateSinglePrivilegeFlagToken(AccessToken, PrivsInToken);
/* Remove the privileges now */
SepRemovePrivilegeToken(AccessToken, PrivsInToken);
PrivsInToken--;
}
}
else
{
if (PrivilegesToBeDeleted != NULL)
{
/* Loop the privileges we've got to delete */
for (PrivsInList = 0; PrivsInList < PrivilegesCount; PrivsInList++)
{
/* Does this privilege exist in the token? */
if (RtlEqualLuid(&AccessToken->Privileges[PrivsInToken].Luid,
&PrivilegesToBeDeleted[PrivsInList].Luid))
{
/* Mark that we found it */
FoundPrivilege = TRUE;
break;
}
}
/* Did we find the privilege? */
if (PrivsInList == PrivilegesCount)
{
/* We didn't, continue with next one */
continue;
}
}
}
/*
* If we have found the target privilege in the token
* based on the privileges list given by the caller
* then begin deleting it.
*/
if (FoundPrivilege)
{
/* Disable the privilege and update the flags */
AccessToken->Privileges[PrivsInToken].Attributes &= ~SE_PRIVILEGE_ENABLED;
SepUpdateSinglePrivilegeFlagToken(AccessToken, PrivsInToken);
/* Delete the privilege */
SepRemovePrivilegeToken(AccessToken, PrivsInToken);
/*
* Adjust the index and reset the FoundPrivilege indicator
* so that we can continue with the next privilege to delete.
*/
PrivsInToken--;
FoundPrivilege = FALSE;
continue;
}
}
/*
* Loop the group SIDs that we want to disable as
* per on the request by the caller.
*/
if (SidsToBeDisabled != NULL)
{
for (GroupsInToken = 0; GroupsInToken < AccessToken->UserAndGroupCount; GroupsInToken++)
{
for (GroupsInList = 0; GroupsInList < RegularGroupsSidCount; GroupsInList++)
{
/* Does this group SID exist in the token? */
if (RtlEqualSid(&AccessToken->UserAndGroups[GroupsInToken].Sid,
&SidsToBeDisabled[GroupsInList].Sid))
{
/* Mark that we found it */
FoundGroup = TRUE;
break;
}
}
/* Did we find the group? */
if (GroupsInList == RegularGroupsSidCount)
{
/* We didn't, continue with next one */
continue;
}
/* If we have found the group, disable it */
if (FoundGroup)
{
/*
* If the acess token belongs to the administrators
* group and this is the target group, we must take
* away TOKEN_HAS_ADMIN_GROUP flag from the token.
*/
if (RtlEqualSid(SeAliasAdminsSid,
&AccessToken->UserAndGroups[GroupsInToken].Sid))
{
AccessToken->TokenFlags &= ~TOKEN_HAS_ADMIN_GROUP;
}
/*
* If the target group that we have found it is the
* owner then from now on it no longer is but the user.
* Therefore assign the default owner index as the user.
*/
if (AccessToken->DefaultOwnerIndex == GroupsInToken)
{
AccessToken->DefaultOwnerIndex = 0;
}
/*
* The principle of disabling a group SID is by
* taking away SE_GROUP_ENABLED_BY_DEFAULT and
* SE_GROUP_ENABLED attributes and assign
* SE_GROUP_USE_FOR_DENY_ONLY. This renders
* SID a "Deny only" SID.
*/
AccessToken->UserAndGroups[GroupsInToken].Attributes &= ~(SE_GROUP_ENABLED | SE_GROUP_ENABLED_BY_DEFAULT);
AccessToken->UserAndGroups[GroupsInToken].Attributes |= SE_GROUP_USE_FOR_DENY_ONLY;
/* Adjust the index and continue with the next group */
GroupsInToken--;
FoundGroup = FALSE;
continue;
}
}
}
/* We've finally filtered the token, return it to the caller */
*FilteredToken = AccessToken;
Status = STATUS_SUCCESS;
DPRINT("SepPerformTokenFiltering(): The token has been filtered!\n");
Quit:
if (!NT_SUCCESS(Status))
{
/* Dereference the created token */
ObDereferenceObject(AccessToken);
}
/* Unlock the source token */
SepReleaseTokenLock(Token);
return Status;
}
/* PUBLIC FUNCTIONS ***********************************************************/
/**
* @brief
* Filters an access token from an existing token, making it more restricted
* than the previous one.
*
* @param[in] ExistingToken
* An existing token for filtering.
*
* @param[in] Flags
* Privilege flag options. This parameter argument influences how the token
* is filtered. Such parameter can be 0. See NtFilterToken syscall for
* more information.
*
* @param[in] SidsToDisable
* Array of SIDs to disable. Such parameter can be NULL.
*
* @param[in] PrivilegesToDelete
* Array of privileges to delete. If DISABLE_MAX_PRIVILEGE flag is specified
* in the Flags parameter, PrivilegesToDelete is ignored.
*
* @param[in] RestrictedSids
* An array of restricted SIDs for the new filtered token. Such parameter
* can be NULL.
*
* @param[out] FilteredToken
* The newly filtered token, returned to the caller.
*
* @return
* Returns STATUS_SUCCESS if the function has successfully completed its
* operations and that the access token has been filtered. STATUS_INVALID_PARAMETER
* is returned if one or more of the parameter are not valid. A failure NTSTATUS code
* is returned otherwise.
*/
NTSTATUS
NTAPI
SeFilterToken(
_In_ PACCESS_TOKEN ExistingToken,
_In_ ULONG Flags,
_In_opt_ PTOKEN_GROUPS SidsToDisable,
_In_opt_ PTOKEN_PRIVILEGES PrivilegesToDelete,
_In_opt_ PTOKEN_GROUPS RestrictedSids,
_Out_ PACCESS_TOKEN *FilteredToken)
{
NTSTATUS Status;
PTOKEN AccessToken;
ULONG PrivilegesCount = 0;
ULONG SidsCount = 0;
ULONG RestrictedSidsCount = 0;
PAGED_CODE();
/* Begin copying the counters */
if (SidsToDisable != NULL)
{
SidsCount = SidsToDisable->GroupCount;
}
if (PrivilegesToDelete != NULL)
{
PrivilegesCount = PrivilegesToDelete->PrivilegeCount;
}
if (RestrictedSids != NULL)
{
RestrictedSidsCount = RestrictedSids->GroupCount;
}
/* Call the internal API */
Status = SepPerformTokenFiltering(ExistingToken,
PrivilegesToDelete->Privileges,
SidsToDisable->Groups,
RestrictedSids->Groups,
PrivilegesCount,
SidsCount,
RestrictedSidsCount,
Flags,
KernelMode,
&AccessToken);
if (!NT_SUCCESS(Status))
{
DPRINT1("SeFilterToken(): Failed to filter the token (Status 0x%lx)\n", Status);
return Status;
}
/* Insert the filtered token */
Status = ObInsertObject(AccessToken,
NULL,
0,
0,
NULL,
NULL);
if (!NT_SUCCESS(Status))
{
DPRINT1("SeFilterToken(): Failed to insert the filtered token (Status 0x%lx)\n", Status);
return Status;
}
/* Return it to the caller */
*FilteredToken = AccessToken;
return Status;
}
/* SYSTEM CALLS ***************************************************************/
/**
* @brief
* Creates an access token.
*
* @param[out] TokenHandle
* The returned created token handle to the caller.
*
* @param[in] DesiredAccess
* The desired access rights for the token that we're creating.
*
* @param[in] ObjectAttributes
* The object attributes for the token object that we're creating.
*
* @param[in] TokenType
* The type of token to assign for the newly created token.
*
* @param[in] AuthenticationId
* Authentication ID that represents the token's identity.
*
* @param[in] ExpirationTime
* Expiration time for the token. If set to -1, the token never expires.
*
* @param[in] TokenUser
* The main user entity for the token to assign.
*
* @param[in] TokenGroups
* Group list of SIDs for the token to assign.
*
* @param[in] TokenPrivileges
* Privileges for the token.
*
* @param[in] TokenOwner
* The main user that owns the newly created token.
*
* @param[in] TokenPrimaryGroup
* The primary group that represents as the main group of the token.
*
* @param[in] TokenDefaultDacl
* Discretionary access control list for the token. This limits on how
* the token can be used, accessed and used by whom.
*
* @param[in] TokenSource
* The source origin of the token who creates it.
*
* @return
* Returns STATUS_SUCCESS if the function has successfully created the token.
* A failure NTSTATUS code is returned otherwise.
*/
__kernel_entry
NTSTATUS
NTAPI
NtCreateToken(
_Out_ PHANDLE TokenHandle,
_In_ ACCESS_MASK DesiredAccess,
_In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
_In_ TOKEN_TYPE TokenType,
_In_ PLUID AuthenticationId,
_In_ PLARGE_INTEGER ExpirationTime,
_In_ PTOKEN_USER TokenUser,
_In_ PTOKEN_GROUPS TokenGroups,
_In_ PTOKEN_PRIVILEGES TokenPrivileges,
_In_opt_ PTOKEN_OWNER TokenOwner,
_In_ PTOKEN_PRIMARY_GROUP TokenPrimaryGroup,
_In_opt_ PTOKEN_DEFAULT_DACL TokenDefaultDacl,
_In_ PTOKEN_SOURCE TokenSource)
{
HANDLE hToken;
KPROCESSOR_MODE PreviousMode;
ULONG PrivilegeCount, GroupCount;
PSID OwnerSid, PrimaryGroupSid;
PACL DefaultDacl;
LARGE_INTEGER LocalExpirationTime = {{0, 0}};
LUID LocalAuthenticationId;
TOKEN_SOURCE LocalTokenSource;
SECURITY_QUALITY_OF_SERVICE LocalSecurityQos;
PLUID_AND_ATTRIBUTES CapturedPrivileges = NULL;
PSID_AND_ATTRIBUTES CapturedUser = NULL;
PSID_AND_ATTRIBUTES CapturedGroups = NULL;
PSID CapturedOwnerSid = NULL;
PSID CapturedPrimaryGroupSid = NULL;
PACL CapturedDefaultDacl = NULL;
ULONG PrivilegesLength, UserLength, GroupsLength;
NTSTATUS Status;
PAGED_CODE();
PreviousMode = ExGetPreviousMode();
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
ProbeForWriteHandle(TokenHandle);
if (ObjectAttributes != NULL)
{
ProbeForRead(ObjectAttributes,
sizeof(OBJECT_ATTRIBUTES),
sizeof(ULONG));
LocalSecurityQos = *(SECURITY_QUALITY_OF_SERVICE*)ObjectAttributes->SecurityQualityOfService;
}
ProbeForRead(AuthenticationId,
sizeof(LUID),
sizeof(ULONG));
LocalAuthenticationId = *AuthenticationId;
LocalExpirationTime = ProbeForReadLargeInteger(ExpirationTime);
ProbeForRead(TokenUser,
sizeof(TOKEN_USER),
sizeof(ULONG));
ProbeForRead(TokenGroups,
sizeof(TOKEN_GROUPS),
sizeof(ULONG));
GroupCount = TokenGroups->GroupCount;
ProbeForRead(TokenPrivileges,
sizeof(TOKEN_PRIVILEGES),
sizeof(ULONG));
PrivilegeCount = TokenPrivileges->PrivilegeCount;
if (TokenOwner != NULL)
{
ProbeForRead(TokenOwner,
sizeof(TOKEN_OWNER),
sizeof(ULONG));
OwnerSid = TokenOwner->Owner;
}
else
{
OwnerSid = NULL;
}
ProbeForRead(TokenPrimaryGroup,
sizeof(TOKEN_PRIMARY_GROUP),
sizeof(ULONG));
PrimaryGroupSid = TokenPrimaryGroup->PrimaryGroup;
if (TokenDefaultDacl != NULL)
{
ProbeForRead(TokenDefaultDacl,
sizeof(TOKEN_DEFAULT_DACL),
sizeof(ULONG));
DefaultDacl = TokenDefaultDacl->DefaultDacl;
}
else
{
DefaultDacl = NULL;
}
ProbeForRead(TokenSource,
sizeof(TOKEN_SOURCE),
sizeof(ULONG));
LocalTokenSource = *TokenSource;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else
{
if (ObjectAttributes != NULL)
LocalSecurityQos = *(SECURITY_QUALITY_OF_SERVICE*)ObjectAttributes->SecurityQualityOfService;
LocalAuthenticationId = *AuthenticationId;
LocalExpirationTime = *ExpirationTime;
GroupCount = TokenGroups->GroupCount;
PrivilegeCount = TokenPrivileges->PrivilegeCount;
OwnerSid = TokenOwner ? TokenOwner->Owner : NULL;
PrimaryGroupSid = TokenPrimaryGroup->PrimaryGroup;
DefaultDacl = TokenDefaultDacl ? TokenDefaultDacl->DefaultDacl : NULL;
LocalTokenSource = *TokenSource;
}
/* Check token type */
if ((TokenType < TokenPrimary) ||
(TokenType > TokenImpersonation))
{
return STATUS_BAD_TOKEN_TYPE;
}
/* Check for token creation privilege */
if (!SeSinglePrivilegeCheck(SeCreateTokenPrivilege, PreviousMode))
{
return STATUS_PRIVILEGE_NOT_HELD;
}
/* Capture the user SID and attributes */
Status = SeCaptureSidAndAttributesArray(&TokenUser->User,
1,
PreviousMode,
NULL,
0,
PagedPool,
FALSE,
&CapturedUser,
&UserLength);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
/* Capture the groups SID and attributes array */
Status = SeCaptureSidAndAttributesArray(&TokenGroups->Groups[0],
GroupCount,
PreviousMode,
NULL,
0,
PagedPool,
FALSE,
&CapturedGroups,
&GroupsLength);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
/* Capture privileges */
Status = SeCaptureLuidAndAttributesArray(&TokenPrivileges->Privileges[0],
PrivilegeCount,
PreviousMode,
NULL,
0,
PagedPool,
FALSE,
&CapturedPrivileges,
&PrivilegesLength);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
/* Capture the token owner SID */
if (TokenOwner != NULL)
{
Status = SepCaptureSid(OwnerSid,
PreviousMode,
PagedPool,
FALSE,
&CapturedOwnerSid);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
}
/* Capture the token primary group SID */
Status = SepCaptureSid(PrimaryGroupSid,
PreviousMode,
PagedPool,
FALSE,
&CapturedPrimaryGroupSid);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
/* Capture DefaultDacl */
if (DefaultDacl != NULL)
{
Status = SepCaptureAcl(DefaultDacl,
PreviousMode,
NonPagedPool,
FALSE,
&CapturedDefaultDacl);
if (!NT_SUCCESS(Status))
{
goto Cleanup;
}
}
/* Call the internal function */
Status = SepCreateToken(&hToken,
PreviousMode,
DesiredAccess,
ObjectAttributes,
TokenType,
LocalSecurityQos.ImpersonationLevel,
&LocalAuthenticationId,
&LocalExpirationTime,
CapturedUser,
GroupCount,
CapturedGroups,
GroupsLength,
PrivilegeCount,
CapturedPrivileges,
CapturedOwnerSid,
CapturedPrimaryGroupSid,
CapturedDefaultDacl,
&LocalTokenSource,
FALSE);
if (NT_SUCCESS(Status))
{
_SEH2_TRY
{
*TokenHandle = hToken;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
}
Cleanup:
/* Release what we captured */
SeReleaseSidAndAttributesArray(CapturedUser, PreviousMode, FALSE);
SeReleaseSidAndAttributesArray(CapturedGroups, PreviousMode, FALSE);
SeReleaseLuidAndAttributesArray(CapturedPrivileges, PreviousMode, FALSE);
SepReleaseSid(CapturedOwnerSid, PreviousMode, FALSE);
SepReleaseSid(CapturedPrimaryGroupSid, PreviousMode, FALSE);
SepReleaseAcl(CapturedDefaultDacl, PreviousMode, FALSE);
return Status;
}
/**
* @brief
* Duplicates a token.
*
* @param[in] ExistingTokenHandle
* An existing token to duplicate.
*
* @param[in] DesiredAccess
* The desired access rights for the new duplicated token.
*
* @param[in] ObjectAttributes
* Object attributes for the new duplicated token.
*
* @param[in] EffectiveOnly
* If set to TRUE, the function removes all the disabled privileges and groups
* of the token to duplicate.
*
* @param[in] TokenType
* Type of token to assign to the duplicated token.
*
* @param[out] NewTokenHandle
* The returned duplicated token handle.
*
* @return
* STATUS_SUCCESS is returned if token duplication has completed successfully.
* STATUS_BAD_IMPERSONATION_LEVEL is returned if the caller erroneously wants
* to raise the impersonation level even though the conditions do not permit
* it. A failure NTSTATUS code is returned otherwise.
*
* @remarks
* Some sources claim 4th param is ImpersonationLevel, but on W2K
* this is certainly NOT true, although I can't say for sure that EffectiveOnly
* is correct either. -Gunnar
* This is true. EffectiveOnly overrides SQOS.EffectiveOnly. - IAI
* NOTE for readers: http://hex.pp.ua/nt/NtDuplicateToken.php is therefore
* wrong in that regard, while MSDN documentation is correct.
*/
_Must_inspect_result_
__kernel_entry
NTSTATUS
NTAPI
NtDuplicateToken(
_In_ HANDLE ExistingTokenHandle,
_In_ ACCESS_MASK DesiredAccess,
_In_opt_ POBJECT_ATTRIBUTES ObjectAttributes,
_In_ BOOLEAN EffectiveOnly,
_In_ TOKEN_TYPE TokenType,
_Out_ PHANDLE NewTokenHandle)
{
KPROCESSOR_MODE PreviousMode;
HANDLE hToken;
PTOKEN Token;
PTOKEN NewToken;
PSECURITY_QUALITY_OF_SERVICE CapturedSecurityQualityOfService;
BOOLEAN QoSPresent;
OBJECT_HANDLE_INFORMATION HandleInformation;
NTSTATUS Status;
PAGED_CODE();
if (TokenType != TokenImpersonation &&
TokenType != TokenPrimary)
{
return STATUS_INVALID_PARAMETER;
}
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
ProbeForWriteHandle(NewTokenHandle);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
Status = SepCaptureSecurityQualityOfService(ObjectAttributes,
PreviousMode,
PagedPool,
FALSE,
&CapturedSecurityQualityOfService,
&QoSPresent);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtDuplicateToken() failed to capture QoS! Status: 0x%x\n", Status);
return Status;
}
Status = ObReferenceObjectByHandle(ExistingTokenHandle,
TOKEN_DUPLICATE,
SeTokenObjectType,
PreviousMode,
(PVOID*)&Token,
&HandleInformation);
if (!NT_SUCCESS(Status))
{
DPRINT1("Failed to reference token (Status 0x%lx)\n", Status);
SepReleaseSecurityQualityOfService(CapturedSecurityQualityOfService,
PreviousMode,
FALSE);
return Status;
}
/*
* Fail, if the original token is an impersonation token and the caller
* tries to raise the impersonation level of the new token above the
* impersonation level of the original token.
*/
if (Token->TokenType == TokenImpersonation)
{
if (QoSPresent &&
CapturedSecurityQualityOfService->ImpersonationLevel >Token->ImpersonationLevel)
{
ObDereferenceObject(Token);
SepReleaseSecurityQualityOfService(CapturedSecurityQualityOfService,
PreviousMode,
FALSE);
return STATUS_BAD_IMPERSONATION_LEVEL;
}
}
/*
* Fail, if a primary token is to be created from an impersonation token
* and and the impersonation level of the impersonation token is below SecurityImpersonation.
*/
if (Token->TokenType == TokenImpersonation &&
TokenType == TokenPrimary &&
Token->ImpersonationLevel < SecurityImpersonation)
{
ObDereferenceObject(Token);
SepReleaseSecurityQualityOfService(CapturedSecurityQualityOfService,
PreviousMode,
FALSE);
return STATUS_BAD_IMPERSONATION_LEVEL;
}
Status = SepDuplicateToken(Token,
ObjectAttributes,
EffectiveOnly,
TokenType,
(QoSPresent ? CapturedSecurityQualityOfService->ImpersonationLevel : SecurityAnonymous),
PreviousMode,
&NewToken);
ObDereferenceObject(Token);
if (NT_SUCCESS(Status))
{
Status = ObInsertObject(NewToken,
NULL,
(DesiredAccess ? DesiredAccess : HandleInformation.GrantedAccess),
0,
NULL,
&hToken);
if (NT_SUCCESS(Status))
{
_SEH2_TRY
{
*NewTokenHandle = hToken;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
}
}
/* Free the captured structure */
SepReleaseSecurityQualityOfService(CapturedSecurityQualityOfService,
PreviousMode,
FALSE);
return Status;
}
/**
* @brief
* Creates an access token in a restricted form
* from the original existing token, that is, such
* action is called filtering.
*
* @param[in] ExistingTokenHandle
* A handle to an access token which is to be filtered.
*
* @param[in] Flags
* Privilege flag options. This parameter argument influences how the
* token's privileges are filtered. For further details see remarks.
*
* @param[in] SidsToDisable
* Array of SIDs to disable. The action of doing so assigns the
* SE_GROUP_USE_FOR_DENY_ONLY attribute to the respective group
* SID and takes away SE_GROUP_ENABLED and SE_GROUP_ENABLED_BY_DEFAULT.
* This parameter can be NULL. This can be a UM pointer.
*
* @param[in] PrivilegesToDelete
* Array of privileges to delete. The function will walk within this
* array to determine if the specified privileges do exist in the
* access token. Any missing privileges gets ignored. This parameter
* can be NULL. This can be a UM pointer.
*
* @param[in] RestrictedSids
* An array list of restricted groups SID to be added in the access
* token. A token that is already restricted the newly added restricted
* SIDs are redundant information in addition to the existing restricted
* SIDs in the token. This parameter can be NULL. This can be a UM pointer.
*
* @param[out] NewTokenHandle
* A new handle to the restricted (filtered) access token. This can be a
* UM pointer.
*
* @return
* Returns STATUS_SUCCESS if the routine has successfully filtered the
* access token. STATUS_INVALID_PARAMETER is returned if one or more
* parameters are not valid (see SepPerformTokenFiltering routine call
* for more information). A failure NTSTATUS code is returned otherwise.
*
* @remarks
* The Flags parameter determines the final outcome of how the privileges
* in an access token are filtered. This parameter can take these supported
* values (these can be combined):
*
* 0 -- Filter the token's privileges in the usual way. The function expects
* that the caller MUST PROVIDE a valid array list of privileges to be
* deleted (that is, PrivilegesToDelete MUSTN'T BE NULL).
*
* DISABLE_MAX_PRIVILEGE -- Disables (deletes) all the privileges except SeChangeNotifyPrivilege
* in the new access token. Bear in mind if this flag is specified
* the routine ignores PrivilegesToDelete.
*
* SANDBOX_INERT -- Stores the TOKEN_SANDBOX_INERT token flag within the access token.
*
* LUA_TOKEN -- The newly filtered access token is a LUA token. This flag is not
* supported in Windows Server 2003.
*
* WRITE_RESTRICTED -- The newly filtered token has the restricted SIDs that are
* considered only when evaluating write access onto the token.
* This value is not supported in Windows Server 2003.
*/
NTSTATUS
NTAPI
NtFilterToken(
_In_ HANDLE ExistingTokenHandle,
_In_ ULONG Flags,
_In_opt_ PTOKEN_GROUPS SidsToDisable,
_In_opt_ PTOKEN_PRIVILEGES PrivilegesToDelete,
_In_opt_ PTOKEN_GROUPS RestrictedSids,
_Out_ PHANDLE NewTokenHandle)
{
PTOKEN Token, FilteredToken;
HANDLE FilteredTokenHandle;
NTSTATUS Status;
KPROCESSOR_MODE PreviousMode;
OBJECT_HANDLE_INFORMATION HandleInfo;
ULONG ResultLength;
ULONG CapturedSidsCount = 0;
ULONG CapturedPrivilegesCount = 0;
ULONG CapturedRestrictedSidsCount = 0;
ULONG ProbeSize = 0;
PSID_AND_ATTRIBUTES CapturedSids = NULL;
PSID_AND_ATTRIBUTES CapturedRestrictedSids = NULL;
PLUID_AND_ATTRIBUTES CapturedPrivileges = NULL;
PAGED_CODE();
PreviousMode = ExGetPreviousMode();
_SEH2_TRY
{
/* Probe SidsToDisable */
if (SidsToDisable != NULL)
{
/* Probe the header */
ProbeForRead(SidsToDisable, sizeof(*SidsToDisable), sizeof(ULONG));
CapturedSidsCount = SidsToDisable->GroupCount;
ProbeSize = FIELD_OFFSET(TOKEN_GROUPS, Groups[CapturedSidsCount]);
ProbeForRead(SidsToDisable, ProbeSize, sizeof(ULONG));
}
/* Probe PrivilegesToDelete */
if (PrivilegesToDelete != NULL)
{
/* Probe the header */
ProbeForRead(PrivilegesToDelete, sizeof(*PrivilegesToDelete), sizeof(ULONG));
CapturedPrivilegesCount = PrivilegesToDelete->PrivilegeCount;
ProbeSize = FIELD_OFFSET(TOKEN_PRIVILEGES, Privileges[CapturedPrivilegesCount]);
ProbeForRead(PrivilegesToDelete, ProbeSize, sizeof(ULONG));
}
/* Probe RestrictedSids */
if (RestrictedSids != NULL)
{
/* Probe the header */
ProbeForRead(RestrictedSids, sizeof(*RestrictedSids), sizeof(ULONG));
CapturedRestrictedSidsCount = RestrictedSids->GroupCount;
ProbeSize = FIELD_OFFSET(TOKEN_GROUPS, Groups[CapturedRestrictedSidsCount]);
ProbeForRead(RestrictedSids, ProbeSize, sizeof(ULONG));
}
/* Probe the handle */
ProbeForWriteHandle(NewTokenHandle);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
/* Reference the token */
Status = ObReferenceObjectByHandle(ExistingTokenHandle,
TOKEN_DUPLICATE,
SeTokenObjectType,
PreviousMode,
(PVOID*)&Token,
&HandleInfo);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to reference the token (Status 0x%lx)\n", Status);
return Status;
}
/* Capture the group SIDs */
if (SidsToDisable != NULL)
{
Status = SeCaptureSidAndAttributesArray(SidsToDisable->Groups,
CapturedSidsCount,
PreviousMode,
NULL,
0,
PagedPool,
TRUE,
&CapturedSids,
&ResultLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to capture the SIDs (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Capture the privileges */
if (PrivilegesToDelete != NULL)
{
Status = SeCaptureLuidAndAttributesArray(PrivilegesToDelete->Privileges,
CapturedPrivilegesCount,
PreviousMode,
NULL,
0,
PagedPool,
TRUE,
&CapturedPrivileges,
&ResultLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to capture the privileges (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Capture the restricted SIDs */
if (RestrictedSids != NULL)
{
Status = SeCaptureSidAndAttributesArray(RestrictedSids->Groups,
CapturedRestrictedSidsCount,
PreviousMode,
NULL,
0,
PagedPool,
TRUE,
&CapturedRestrictedSids,
&ResultLength);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to capture the restricted SIDs (Status 0x%lx)\n", Status);
goto Quit;
}
}
/* Call the internal API */
Status = SepPerformTokenFiltering(Token,
CapturedPrivileges,
CapturedSids,
CapturedRestrictedSids,
CapturedPrivilegesCount,
CapturedSidsCount,
CapturedRestrictedSidsCount,
Flags,
PreviousMode,
&FilteredToken);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to filter the token (Status 0x%lx)\n", Status);
goto Quit;
}
/* Insert the filtered token and retrieve a handle to it */
Status = ObInsertObject(FilteredToken,
NULL,
HandleInfo.GrantedAccess,
0,
NULL,
&FilteredTokenHandle);
if (!NT_SUCCESS(Status))
{
DPRINT1("NtFilterToken(): Failed to insert the filtered token (Status 0x%lx)\n", Status);
goto Quit;
}
/* And return it to the caller once we're done */
_SEH2_TRY
{
*NewTokenHandle = FilteredTokenHandle;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
_SEH2_YIELD(goto Quit);
}
_SEH2_END;
Quit:
/* Dereference the token */
ObDereferenceObject(Token);
/* Release all the captured data */
if (CapturedSids != NULL)
{
SeReleaseSidAndAttributesArray(CapturedSids,
PreviousMode,
TRUE);
}
if (CapturedPrivileges != NULL)
{
SeReleaseLuidAndAttributesArray(CapturedPrivileges,
PreviousMode,
TRUE);
}
if (CapturedRestrictedSids != NULL)
{
SeReleaseSidAndAttributesArray(CapturedRestrictedSids,
PreviousMode,
TRUE);
}
return Status;
}
/* EOF */