reactos/ntoskrnl/se/sid.c
unknown 310563aece
[NTOS:SE] Let SepGetSidFromAce figure out the ACE type
As the commit title says. Instead of having the caller figuring out what
the ACE type should be of the ACE.
2023-08-23 17:54:47 +02:00

991 lines
35 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
* PURPOSE: Security Identifier (SID) implementation support and handling
* COPYRIGHT: Copyright David Welch <welch@cwcom.net>
*/
/* INCLUDES *******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
/* GLOBALS ********************************************************************/
#define SE_MAXIMUM_GROUP_LIMIT 0x1000
SID_IDENTIFIER_AUTHORITY SeNullSidAuthority = {SECURITY_NULL_SID_AUTHORITY};
SID_IDENTIFIER_AUTHORITY SeWorldSidAuthority = {SECURITY_WORLD_SID_AUTHORITY};
SID_IDENTIFIER_AUTHORITY SeLocalSidAuthority = {SECURITY_LOCAL_SID_AUTHORITY};
SID_IDENTIFIER_AUTHORITY SeCreatorSidAuthority = {SECURITY_CREATOR_SID_AUTHORITY};
SID_IDENTIFIER_AUTHORITY SeNtSidAuthority = {SECURITY_NT_AUTHORITY};
PSID SeNullSid = NULL;
PSID SeWorldSid = NULL;
PSID SeLocalSid = NULL;
PSID SeCreatorOwnerSid = NULL;
PSID SeCreatorGroupSid = NULL;
PSID SeCreatorOwnerServerSid = NULL;
PSID SeCreatorGroupServerSid = NULL;
PSID SeNtAuthoritySid = NULL;
PSID SeDialupSid = NULL;
PSID SeNetworkSid = NULL;
PSID SeBatchSid = NULL;
PSID SeInteractiveSid = NULL;
PSID SeServiceSid = NULL;
PSID SePrincipalSelfSid = NULL;
PSID SeLocalSystemSid = NULL;
PSID SeAuthenticatedUserSid = NULL;
PSID SeRestrictedCodeSid = NULL;
PSID SeAliasAdminsSid = NULL;
PSID SeAliasUsersSid = NULL;
PSID SeAliasGuestsSid = NULL;
PSID SeAliasPowerUsersSid = NULL;
PSID SeAliasAccountOpsSid = NULL;
PSID SeAliasSystemOpsSid = NULL;
PSID SeAliasPrintOpsSid = NULL;
PSID SeAliasBackupOpsSid = NULL;
PSID SeAuthenticatedUsersSid = NULL;
PSID SeRestrictedSid = NULL;
PSID SeAnonymousLogonSid = NULL;
PSID SeLocalServiceSid = NULL;
PSID SeNetworkServiceSid = NULL;
typedef struct _SID_VALIDATE
{
UCHAR SubAuthorityCount;
PISID ProbeSid;
} SID_VALIDATE, *PSID_VALIDATE;
/* FUNCTIONS ******************************************************************/
/**
* @brief
* Frees all the known initialized SIDs in the system from the memory.
*
* @return
* Nothing.
*/
VOID
NTAPI
FreeInitializedSids(VOID)
{
if (SeNullSid) ExFreePoolWithTag(SeNullSid, TAG_SID);
if (SeWorldSid) ExFreePoolWithTag(SeWorldSid, TAG_SID);
if (SeLocalSid) ExFreePoolWithTag(SeLocalSid, TAG_SID);
if (SeCreatorOwnerSid) ExFreePoolWithTag(SeCreatorOwnerSid, TAG_SID);
if (SeCreatorGroupSid) ExFreePoolWithTag(SeCreatorGroupSid, TAG_SID);
if (SeCreatorOwnerServerSid) ExFreePoolWithTag(SeCreatorOwnerServerSid, TAG_SID);
if (SeCreatorGroupServerSid) ExFreePoolWithTag(SeCreatorGroupServerSid, TAG_SID);
if (SeNtAuthoritySid) ExFreePoolWithTag(SeNtAuthoritySid, TAG_SID);
if (SeDialupSid) ExFreePoolWithTag(SeDialupSid, TAG_SID);
if (SeNetworkSid) ExFreePoolWithTag(SeNetworkSid, TAG_SID);
if (SeBatchSid) ExFreePoolWithTag(SeBatchSid, TAG_SID);
if (SeInteractiveSid) ExFreePoolWithTag(SeInteractiveSid, TAG_SID);
if (SeServiceSid) ExFreePoolWithTag(SeServiceSid, TAG_SID);
if (SePrincipalSelfSid) ExFreePoolWithTag(SePrincipalSelfSid, TAG_SID);
if (SeLocalSystemSid) ExFreePoolWithTag(SeLocalSystemSid, TAG_SID);
if (SeAuthenticatedUserSid) ExFreePoolWithTag(SeAuthenticatedUserSid, TAG_SID);
if (SeRestrictedCodeSid) ExFreePoolWithTag(SeRestrictedCodeSid, TAG_SID);
if (SeAliasAdminsSid) ExFreePoolWithTag(SeAliasAdminsSid, TAG_SID);
if (SeAliasUsersSid) ExFreePoolWithTag(SeAliasUsersSid, TAG_SID);
if (SeAliasGuestsSid) ExFreePoolWithTag(SeAliasGuestsSid, TAG_SID);
if (SeAliasPowerUsersSid) ExFreePoolWithTag(SeAliasPowerUsersSid, TAG_SID);
if (SeAliasAccountOpsSid) ExFreePoolWithTag(SeAliasAccountOpsSid, TAG_SID);
if (SeAliasSystemOpsSid) ExFreePoolWithTag(SeAliasSystemOpsSid, TAG_SID);
if (SeAliasPrintOpsSid) ExFreePoolWithTag(SeAliasPrintOpsSid, TAG_SID);
if (SeAliasBackupOpsSid) ExFreePoolWithTag(SeAliasBackupOpsSid, TAG_SID);
if (SeAuthenticatedUsersSid) ExFreePoolWithTag(SeAuthenticatedUsersSid, TAG_SID);
if (SeRestrictedSid) ExFreePoolWithTag(SeRestrictedSid, TAG_SID);
if (SeAnonymousLogonSid) ExFreePoolWithTag(SeAnonymousLogonSid, TAG_SID);
}
/**
* @brief
* Initializes all the SIDs known in the system.
*
* @return
* Returns TRUE if all the SIDs have been initialized,
* FALSE otherwise.
*/
CODE_SEG("INIT")
BOOLEAN
NTAPI
SepInitSecurityIDs(VOID)
{
ULONG SidLength0;
ULONG SidLength1;
ULONG SidLength2;
PULONG SubAuthority;
SidLength0 = RtlLengthRequiredSid(0);
SidLength1 = RtlLengthRequiredSid(1);
SidLength2 = RtlLengthRequiredSid(2);
/* create NullSid */
SeNullSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeWorldSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeLocalSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeCreatorOwnerSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeCreatorGroupSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeCreatorOwnerServerSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeCreatorGroupServerSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeNtAuthoritySid = ExAllocatePoolWithTag(PagedPool, SidLength0, TAG_SID);
SeDialupSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeNetworkSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeBatchSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeInteractiveSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeServiceSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SePrincipalSelfSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeLocalSystemSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeAuthenticatedUserSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeRestrictedCodeSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeAliasAdminsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasUsersSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasGuestsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasPowerUsersSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasAccountOpsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasSystemOpsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasPrintOpsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAliasBackupOpsSid = ExAllocatePoolWithTag(PagedPool, SidLength2, TAG_SID);
SeAuthenticatedUsersSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeRestrictedSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeAnonymousLogonSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeLocalServiceSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
SeNetworkServiceSid = ExAllocatePoolWithTag(PagedPool, SidLength1, TAG_SID);
if (SeNullSid == NULL || SeWorldSid == NULL ||
SeLocalSid == NULL || SeCreatorOwnerSid == NULL ||
SeCreatorGroupSid == NULL || SeCreatorOwnerServerSid == NULL ||
SeCreatorGroupServerSid == NULL || SeNtAuthoritySid == NULL ||
SeDialupSid == NULL || SeNetworkSid == NULL || SeBatchSid == NULL ||
SeInteractiveSid == NULL || SeServiceSid == NULL ||
SePrincipalSelfSid == NULL || SeLocalSystemSid == NULL ||
SeAuthenticatedUserSid == NULL || SeRestrictedCodeSid == NULL ||
SeAliasAdminsSid == NULL || SeAliasUsersSid == NULL ||
SeAliasGuestsSid == NULL || SeAliasPowerUsersSid == NULL ||
SeAliasAccountOpsSid == NULL || SeAliasSystemOpsSid == NULL ||
SeAliasPrintOpsSid == NULL || SeAliasBackupOpsSid == NULL ||
SeAuthenticatedUsersSid == NULL || SeRestrictedSid == NULL ||
SeAnonymousLogonSid == NULL || SeLocalServiceSid == NULL ||
SeNetworkServiceSid == NULL)
{
FreeInitializedSids();
return FALSE;
}
RtlInitializeSid(SeNullSid, &SeNullSidAuthority, 1);
RtlInitializeSid(SeWorldSid, &SeWorldSidAuthority, 1);
RtlInitializeSid(SeLocalSid, &SeLocalSidAuthority, 1);
RtlInitializeSid(SeCreatorOwnerSid, &SeCreatorSidAuthority, 1);
RtlInitializeSid(SeCreatorGroupSid, &SeCreatorSidAuthority, 1);
RtlInitializeSid(SeCreatorOwnerServerSid, &SeCreatorSidAuthority, 1);
RtlInitializeSid(SeCreatorGroupServerSid, &SeCreatorSidAuthority, 1);
RtlInitializeSid(SeNtAuthoritySid, &SeNtSidAuthority, 0);
RtlInitializeSid(SeDialupSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeNetworkSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeBatchSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeInteractiveSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeServiceSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SePrincipalSelfSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeLocalSystemSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeAuthenticatedUserSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeRestrictedCodeSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeAliasAdminsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasUsersSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasGuestsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasPowerUsersSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasAccountOpsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasSystemOpsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasPrintOpsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAliasBackupOpsSid, &SeNtSidAuthority, 2);
RtlInitializeSid(SeAuthenticatedUsersSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeRestrictedSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeAnonymousLogonSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeLocalServiceSid, &SeNtSidAuthority, 1);
RtlInitializeSid(SeNetworkServiceSid, &SeNtSidAuthority, 1);
SubAuthority = RtlSubAuthoritySid(SeNullSid, 0);
*SubAuthority = SECURITY_NULL_RID;
SubAuthority = RtlSubAuthoritySid(SeWorldSid, 0);
*SubAuthority = SECURITY_WORLD_RID;
SubAuthority = RtlSubAuthoritySid(SeLocalSid, 0);
*SubAuthority = SECURITY_LOCAL_RID;
SubAuthority = RtlSubAuthoritySid(SeCreatorOwnerSid, 0);
*SubAuthority = SECURITY_CREATOR_OWNER_RID;
SubAuthority = RtlSubAuthoritySid(SeCreatorGroupSid, 0);
*SubAuthority = SECURITY_CREATOR_GROUP_RID;
SubAuthority = RtlSubAuthoritySid(SeCreatorOwnerServerSid, 0);
*SubAuthority = SECURITY_CREATOR_OWNER_SERVER_RID;
SubAuthority = RtlSubAuthoritySid(SeCreatorGroupServerSid, 0);
*SubAuthority = SECURITY_CREATOR_GROUP_SERVER_RID;
SubAuthority = RtlSubAuthoritySid(SeDialupSid, 0);
*SubAuthority = SECURITY_DIALUP_RID;
SubAuthority = RtlSubAuthoritySid(SeNetworkSid, 0);
*SubAuthority = SECURITY_NETWORK_RID;
SubAuthority = RtlSubAuthoritySid(SeBatchSid, 0);
*SubAuthority = SECURITY_BATCH_RID;
SubAuthority = RtlSubAuthoritySid(SeInteractiveSid, 0);
*SubAuthority = SECURITY_INTERACTIVE_RID;
SubAuthority = RtlSubAuthoritySid(SeServiceSid, 0);
*SubAuthority = SECURITY_SERVICE_RID;
SubAuthority = RtlSubAuthoritySid(SePrincipalSelfSid, 0);
*SubAuthority = SECURITY_PRINCIPAL_SELF_RID;
SubAuthority = RtlSubAuthoritySid(SeLocalSystemSid, 0);
*SubAuthority = SECURITY_LOCAL_SYSTEM_RID;
SubAuthority = RtlSubAuthoritySid(SeAuthenticatedUserSid, 0);
*SubAuthority = SECURITY_AUTHENTICATED_USER_RID;
SubAuthority = RtlSubAuthoritySid(SeRestrictedCodeSid, 0);
*SubAuthority = SECURITY_RESTRICTED_CODE_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasAdminsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasAdminsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_ADMINS;
SubAuthority = RtlSubAuthoritySid(SeAliasUsersSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasUsersSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_USERS;
SubAuthority = RtlSubAuthoritySid(SeAliasGuestsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasGuestsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_GUESTS;
SubAuthority = RtlSubAuthoritySid(SeAliasPowerUsersSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasPowerUsersSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_POWER_USERS;
SubAuthority = RtlSubAuthoritySid(SeAliasAccountOpsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasAccountOpsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_ACCOUNT_OPS;
SubAuthority = RtlSubAuthoritySid(SeAliasSystemOpsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasSystemOpsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_SYSTEM_OPS;
SubAuthority = RtlSubAuthoritySid(SeAliasPrintOpsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasPrintOpsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_PRINT_OPS;
SubAuthority = RtlSubAuthoritySid(SeAliasBackupOpsSid, 0);
*SubAuthority = SECURITY_BUILTIN_DOMAIN_RID;
SubAuthority = RtlSubAuthoritySid(SeAliasBackupOpsSid, 1);
*SubAuthority = DOMAIN_ALIAS_RID_BACKUP_OPS;
SubAuthority = RtlSubAuthoritySid(SeAuthenticatedUsersSid, 0);
*SubAuthority = SECURITY_AUTHENTICATED_USER_RID;
SubAuthority = RtlSubAuthoritySid(SeRestrictedSid, 0);
*SubAuthority = SECURITY_RESTRICTED_CODE_RID;
SubAuthority = RtlSubAuthoritySid(SeAnonymousLogonSid, 0);
*SubAuthority = SECURITY_ANONYMOUS_LOGON_RID;
SubAuthority = RtlSubAuthoritySid(SeLocalServiceSid, 0);
*SubAuthority = SECURITY_LOCAL_SERVICE_RID;
SubAuthority = RtlSubAuthoritySid(SeNetworkServiceSid, 0);
*SubAuthority = SECURITY_NETWORK_SERVICE_RID;
return TRUE;
}
/**
* @brief
* Captures a SID.
*
* @param[in] InputSid
* A valid security identifier to be captured.
*
* @param[in] AccessMode
* Processor level access mode.
*
* @param[in] PoolType
* Pool memory type for the captured SID to assign upon
* allocation.
*
* @param[in] CaptureIfKernel
* If set to TRUE, the capturing is done within the kernel.
* Otherwise the capturing is done in a kernel mode driver.
*
* @param[out] CapturedSid
* The captured security identifier, returned to the caller.
*
* @return
* Returns STATUS_SUCCESS if the SID was captured. STATUS_INSUFFICIENT_RESOURCES
* is returned if memory pool allocation for the captured SID has failed.
*/
NTSTATUS
NTAPI
SepCaptureSid(
_In_ PSID InputSid,
_In_ KPROCESSOR_MODE AccessMode,
_In_ POOL_TYPE PoolType,
_In_ BOOLEAN CaptureIfKernel,
_Out_ PSID *CapturedSid)
{
ULONG SidSize = 0;
PISID NewSid, Sid = (PISID)InputSid;
PAGED_CODE();
if (AccessMode != KernelMode)
{
_SEH2_TRY
{
ProbeForRead(Sid, FIELD_OFFSET(SID, SubAuthority), sizeof(UCHAR));
SidSize = RtlLengthRequiredSid(Sid->SubAuthorityCount);
ProbeForRead(Sid, SidSize, sizeof(UCHAR));
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
/* Allocate a SID and copy it */
NewSid = ExAllocatePoolWithTag(PoolType, SidSize, TAG_SID);
if (!NewSid)
return STATUS_INSUFFICIENT_RESOURCES;
_SEH2_TRY
{
RtlCopyMemory(NewSid, Sid, SidSize);
*CapturedSid = NewSid;
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Free the SID and return the exception code */
ExFreePoolWithTag(NewSid, TAG_SID);
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
}
else if (!CaptureIfKernel)
{
*CapturedSid = InputSid;
}
else
{
SidSize = RtlLengthRequiredSid(Sid->SubAuthorityCount);
/* Allocate a SID and copy it */
NewSid = ExAllocatePoolWithTag(PoolType, SidSize, TAG_SID);
if (NewSid == NULL)
return STATUS_INSUFFICIENT_RESOURCES;
RtlCopyMemory(NewSid, Sid, SidSize);
*CapturedSid = NewSid;
}
return STATUS_SUCCESS;
}
/**
* @brief
* Releases a captured SID.
*
* @param[in] CapturedSid
* The captured SID to be released.
*
* @param[in] AccessMode
* Processor level access mode.
*
* @param[in] CaptureIfKernel
* If set to TRUE, the releasing is done within the kernel.
* Otherwise the releasing is done in a kernel mode driver.
*
* @return
* Nothing.
*/
VOID
NTAPI
SepReleaseSid(
_In_ PSID CapturedSid,
_In_ KPROCESSOR_MODE AccessMode,
_In_ BOOLEAN CaptureIfKernel)
{
PAGED_CODE();
if (CapturedSid != NULL &&
(AccessMode != KernelMode ||
(AccessMode == KernelMode && CaptureIfKernel)))
{
ExFreePoolWithTag(CapturedSid, TAG_SID);
}
}
/**
* @brief
* Checks if a SID is present in a token.
*
* @param[in] _Token
* A valid token object.
*
* @param[in] PrincipalSelfSid
* A principal self SID.
*
* @param[in] _Sid
* A regular SID.
*
* @param[in] Deny
* If set to TRUE, the caller expected that a SID in a token
* must be a deny-only SID, that is, access checks are performed
* only for deny-only ACEs of the said SID.
*
* @param[in] Restricted
* If set to TRUE, the caller expects that a SID in a token is
* restricted (by the general definition, a token is restricted).
*
* @return
* Returns TRUE if the specified SID in the call is present in the token,
* FALSE otherwise.
*/
BOOLEAN
NTAPI
SepSidInTokenEx(
_In_ PACCESS_TOKEN _Token,
_In_ PSID PrincipalSelfSid,
_In_ PSID _Sid,
_In_ BOOLEAN Deny,
_In_ BOOLEAN Restricted)
{
ULONG SidIndex;
PTOKEN Token = (PTOKEN)_Token;
PISID TokenSid, Sid = (PISID)_Sid;
PSID_AND_ATTRIBUTES SidAndAttributes;
ULONG SidCount, SidLength;
USHORT SidMetadata;
PAGED_CODE();
/* Check if a principal SID was given, and this is our current SID already */
if ((PrincipalSelfSid) && (RtlEqualSid(SePrincipalSelfSid, Sid)))
{
/* Just use the principal SID in this case */
Sid = PrincipalSelfSid;
}
/* Check if this is a restricted token or not */
if (Restricted)
{
/* Use the restricted SIDs and count */
SidAndAttributes = Token->RestrictedSids;
SidCount = Token->RestrictedSidCount;
}
else
{
/* Use the normal SIDs and count */
SidAndAttributes = Token->UserAndGroups;
SidCount = Token->UserAndGroupCount;
}
/* Do checks here by hand instead of the usual 4 function calls */
SidLength = FIELD_OFFSET(SID,
SubAuthority[Sid->SubAuthorityCount]);
SidMetadata = *(PUSHORT)&Sid->Revision;
/* Loop every SID */
for (SidIndex = 0; SidIndex < SidCount; SidIndex++)
{
TokenSid = (PISID)SidAndAttributes->Sid;
#if SE_SID_DEBUG
UNICODE_STRING sidString;
RtlConvertSidToUnicodeString(&sidString, TokenSid, TRUE);
DPRINT1("SID in Token: %wZ\n", &sidString);
RtlFreeUnicodeString(&sidString);
#endif
/* Check if the SID metadata matches */
if (*(PUSHORT)&TokenSid->Revision == SidMetadata)
{
/* Check if the SID data matches */
if (RtlEqualMemory(Sid, TokenSid, SidLength))
{
/*
* Check if the group is enabled, or used for deny only.
* Otherwise we have to check if this is the first user.
* We understand that by looking if this SID is not
* restricted, this is the first element we are iterating
* and that it doesn't have SE_GROUP_USE_FOR_DENY_ONLY
* attribute.
*/
if ((!Restricted && (SidIndex == 0) && !(SidAndAttributes->Attributes & SE_GROUP_USE_FOR_DENY_ONLY)) ||
(SidAndAttributes->Attributes & SE_GROUP_ENABLED) ||
((Deny) && (SidAndAttributes->Attributes & SE_GROUP_USE_FOR_DENY_ONLY)))
{
/* SID is present */
return TRUE;
}
else
{
/* SID is not present */
return FALSE;
}
}
}
/* Move to the next SID */
SidAndAttributes++;
}
/* SID is not present */
return FALSE;
}
/**
* @brief
* Checks if a SID is present in a token.
*
* @param[in] _Token
* A valid token object.
*
* @param[in] _Sid
* A regular SID.
*
* @return
* Returns TRUE if the specified SID in the call is present in the token,
* FALSE otherwise.
*/
BOOLEAN
NTAPI
SepSidInToken(
_In_ PACCESS_TOKEN _Token,
_In_ PSID Sid)
{
/* Call extended API */
return SepSidInTokenEx(_Token, NULL, Sid, FALSE, FALSE);
}
/**
* @brief
* Captures a security identifier from a
* given access control entry. This identifier
* is valid for the whole of its lifetime.
*
* @param[in] Ace
* A pointer to an access control entry, which
* can be obtained from a DACL.
*
* @return
* Returns a pointer to a security identifier (SID),
* otherwise NULL is returned if an unsupported ACE
* type was given to the function.
*/
PSID
NTAPI
SepGetSidFromAce(
_In_ PACE Ace)
{
PULONG Flags;
ULONG GuidSize = 0;
PSID Sid = NULL;
PAGED_CODE();
/* Sanity check */
ASSERT(Ace);
/* Obtain the SID based upon ACE type */
switch (Ace->Header.AceType)
{
case ACCESS_DENIED_ACE_TYPE:
case ACCESS_ALLOWED_ACE_TYPE:
case SYSTEM_AUDIT_ACE_TYPE:
case SYSTEM_ALARM_ACE_TYPE:
{
Sid = (PSID)&((PKNOWN_ACE)Ace)->SidStart;
break;
}
case ACCESS_DENIED_OBJECT_ACE_TYPE:
case ACCESS_ALLOWED_OBJECT_ACE_TYPE:
{
Flags = (PULONG)&((PKNOWN_OBJECT_ACE)Ace)->Flags;
if (*Flags & ACE_OBJECT_TYPE_PRESENT)
{
GuidSize += sizeof(GUID);
}
if (*Flags & ACE_INHERITED_OBJECT_TYPE_PRESENT)
{
GuidSize += sizeof(GUID);
}
Sid = (PSID)((ULONG_PTR)&((PKNOWN_OBJECT_ACE)Ace)->SidStart + GuidSize);
break;
}
default:
{
DPRINT1("SepGetSidFromAce(): Unknown ACE type (Ace 0x%p, Type %u)\n", Ace, Ace->Header.AceType);
break;
}
}
return Sid;
}
/**
* @brief
* Captures a SID with attributes.
*
* @param[in] SrcSidAndAttributes
* Source of the SID with attributes to be captured.
*
* @param[in] AttributeCount
* The number count of attributes, in total.
*
* @param[in] PreviousMode
* Processor access level mode.
*
* @param[in] AllocatedMem
* The allocated memory buffer for the captured SID. If the caller
* supplies no allocated block of memory then the function will
* allocate some buffer block of memory for the captured SID
* automatically.
*
* @param[in] AllocatedLength
* The length of the buffer that points to the allocated memory,
* in bytes.
*
* @param[in] PoolType
* The pool type for the captured SID and attributes to assign.
*
* @param[in] CaptureIfKernel
* If set to TRUE, the capturing is done within the kernel.
* Otherwise the capturing is done in a kernel mode driver.
*
* @param[out] CapturedSidAndAttributes
* The captured SID and attributes.
*
* @param[out] ResultLength
* The length of the captured SID and attributes, in bytes.
*
* @return
* Returns STATUS_SUCCESS if SID and attributes capturing
* has been completed successfully. STATUS_INVALID_PARAMETER
* is returned if the count of attributes exceeds the maximum
* threshold that the kernel can permit, with the purpose of
* avoiding integer overflows. STATUS_INSUFFICIENT_RESOURCES
* is returned if memory pool allocation for the captured SID has failed.
* STATUS_BUFFER_TOO_SMALL is returned if the length of the allocated
* buffer is less than the required size. STATUS_INVALID_SID is returned
* if a SID doesn't meet certain requirements to be considered a valid
* SID by the security manager. A failure NTSTATUS code is returned
* otherwise.
*
* @remarks
* A security identifier (SID) is a variable-length data structure that
* can change in size over time, depending on the factors that influence
* this effect in question. An attacker can take advantage of this fact
* and can potentially modify certain properties of a SID making it
* different in size than it was originally before. This is what we'd
* call, a TOCTOU vulnerability.
*
* For this reason, the logic of copying the SIDs and their attributes
* into a new buffer goes like this: first, allocate a buffer array
* that just holds the lengths and subauthority count of each SID.
* Such information is copied in the first loop. Then in a second loop,
* iterate over the array with SID provided and copy them into the final
* array. The moment we're doing this, validate the lengths of each SID
* basing upon the captured lengths we've got before. In this way we
* ensure that the SIDs have remained intact. The validation checks are
* done in user mode as a general rule that we just cannot trust UM and
* whatever data is coming from it.
*/
NTSTATUS
NTAPI
SeCaptureSidAndAttributesArray(
_In_ PSID_AND_ATTRIBUTES SrcSidAndAttributes,
_In_ ULONG AttributeCount,
_In_ KPROCESSOR_MODE PreviousMode,
_In_opt_ PVOID AllocatedMem,
_In_ ULONG AllocatedLength,
_In_ POOL_TYPE PoolType,
_In_ BOOLEAN CaptureIfKernel,
_Out_ PSID_AND_ATTRIBUTES *CapturedSidAndAttributes,
_Out_ PULONG ResultLength)
{
ULONG ArraySize, RequiredLength, SidLength, i;
ULONG TempArrayValidate, TempLengthValidate;
PSID_AND_ATTRIBUTES SidAndAttributes;
_SEH2_VOLATILE PSID_VALIDATE ValidateArray;
PUCHAR CurrentDest;
PISID Sid;
NTSTATUS Status;
PAGED_CODE();
ValidateArray = NULL;
SidAndAttributes = NULL;
*CapturedSidAndAttributes = NULL;
*ResultLength = 0;
if (AttributeCount == 0)
{
return STATUS_SUCCESS;
}
if (AttributeCount > SE_MAXIMUM_GROUP_LIMIT)
{
DPRINT1("SeCaptureSidAndAttributesArray(): Maximum group limit exceeded!\n");
return STATUS_INVALID_PARAMETER;
}
if ((PreviousMode == KernelMode) && !CaptureIfKernel)
{
*CapturedSidAndAttributes = SrcSidAndAttributes;
return STATUS_SUCCESS;
}
ArraySize = AttributeCount * sizeof(SID_AND_ATTRIBUTES);
RequiredLength = ALIGN_UP_BY(ArraySize, sizeof(ULONG));
if (PreviousMode != KernelMode)
{
/* Check for user mode data */
_SEH2_TRY
{
/* First probe the whole array */
ProbeForRead(SrcSidAndAttributes, ArraySize, sizeof(ULONG));
/* We're in user mode, set up the size for the temporary array */
TempArrayValidate = AttributeCount * sizeof(SID_VALIDATE);
TempLengthValidate = ALIGN_UP_BY(TempArrayValidate, sizeof(ULONG));
/*
* Allocate a buffer for the array that we're going to
* temporarily hold the subauthority count and the SID
* elements. We'll be going to use this array to perform
* validation checks later.
*/
ValidateArray = ExAllocatePoolWithTag(PoolType | POOL_RAISE_IF_ALLOCATION_FAILURE,
TempLengthValidate,
TAG_SID_VALIDATE);
/* Loop the array elements */
for (i = 0; i < AttributeCount; i++)
{
/* Get the SID and probe the minimal structure */
Sid = SrcSidAndAttributes[i].Sid;
ProbeForRead(Sid, sizeof(*Sid), sizeof(ULONG));
/*
* Capture the subauthority count and hold it
* into the temporary array for later validation.
* This way we ensure that the said count of each
* SID has remained the same.
*/
ValidateArray[i].SubAuthorityCount = Sid->SubAuthorityCount;
/* Capture the SID */
ValidateArray[i].ProbeSid = Sid;
/* Calculate the SID length and probe the full SID */
SidLength = RtlLengthRequiredSid(ValidateArray[i].SubAuthorityCount);
ProbeForRead(ValidateArray[i].ProbeSid, SidLength, sizeof(ULONG));
/* Add the aligned length to the required length */
RequiredLength += ALIGN_UP_BY(SidLength, sizeof(ULONG));
}
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
_SEH2_YIELD(goto Cleanup);
}
_SEH2_END;
}
else
{
/* Loop the array elements */
for (i = 0; i < AttributeCount; i++)
{
/* Get the SID and it's length */
Sid = SrcSidAndAttributes[i].Sid;
SidLength = RtlLengthRequiredSid(Sid->SubAuthorityCount);
/* Add the aligned length to the required length */
RequiredLength += ALIGN_UP_BY(SidLength, sizeof(ULONG));
}
}
/* Assume success */
Status = STATUS_SUCCESS;
*ResultLength = RequiredLength;
/* Check if we have no buffer */
if (AllocatedMem == NULL)
{
/* Allocate a new buffer */
SidAndAttributes = ExAllocatePoolWithTag(PoolType,
RequiredLength,
TAG_SID_AND_ATTRIBUTES);
if (SidAndAttributes == NULL)
{
DPRINT1("SeCaptureSidAndAttributesArray(): Failed to allocate memory for SID and attributes array (requested size -> %lu)!\n", RequiredLength);
Status = STATUS_INSUFFICIENT_RESOURCES;
goto Cleanup;
}
}
/* Otherwise check if the buffer is large enough */
else if (AllocatedLength >= RequiredLength)
{
/* Buffer is large enough, use it */
SidAndAttributes = AllocatedMem;
}
else
{
/* Buffer is too small, fail */
DPRINT1("SeCaptureSidAndAttributesArray(): The provided buffer is small (expected size -> %lu || current size -> %lu)!\n", RequiredLength, AllocatedLength);
Status = STATUS_BUFFER_TOO_SMALL;
goto Cleanup;
}
*CapturedSidAndAttributes = SidAndAttributes;
/* Check again for user mode */
if (PreviousMode != KernelMode)
{
_SEH2_TRY
{
/* The rest of the data starts after the array */
CurrentDest = (PUCHAR)SidAndAttributes;
CurrentDest += ALIGN_UP_BY(ArraySize, sizeof(ULONG));
/* Loop the array elements */
for (i = 0; i < AttributeCount; i++)
{
/*
* Get the SID length from the subauthority
* count we've captured before.
*/
SidLength = RtlLengthRequiredSid(ValidateArray[i].SubAuthorityCount);
/* Copy attributes */
SidAndAttributes[i].Attributes = SrcSidAndAttributes[i].Attributes;
/* Copy the SID to the current destination address */
SidAndAttributes[i].Sid = (PSID)CurrentDest;
RtlCopyMemory(CurrentDest, ValidateArray[i].ProbeSid, SidLength);
/* Obtain the SID we've captured before for validation */
Sid = SidAndAttributes[i].Sid;
/* Validate that the subauthority count hasn't changed */
if (ValidateArray[i].SubAuthorityCount !=
Sid->SubAuthorityCount)
{
/* It's changed, bail out */
DPRINT1("SeCaptureSidAndAttributesArray(): The subauthority counts have changed (captured count -> %u || current count -> %u)\n",
ValidateArray[i].SubAuthorityCount, Sid->SubAuthorityCount);
Status = STATUS_INVALID_SID;
goto Cleanup;
}
/* Validate that the SID length is the same */
if (SidLength != RtlLengthSid(Sid))
{
/* They're no longer the same, bail out */
DPRINT1("SeCaptureSidAndAttributesArray(): The SID lengths have changed (captured length -> %lu || current length -> %lu)\n",
SidLength, RtlLengthSid(Sid));
Status = STATUS_INVALID_SID;
goto Cleanup;
}
/* Check that the SID is valid */
if (!RtlValidSid(Sid))
{
DPRINT1("SeCaptureSidAndAttributesArray(): The SID is not valid!\n");
Status = STATUS_INVALID_SID;
goto Cleanup;
}
/* Update the current destination address */
CurrentDest += ALIGN_UP_BY(SidLength, sizeof(ULONG));
}
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
}
else
{
/* The rest of the data starts after the array */
CurrentDest = (PUCHAR)SidAndAttributes;
CurrentDest += ALIGN_UP_BY(ArraySize, sizeof(ULONG));
/* Loop the array elements */
for (i = 0; i < AttributeCount; i++)
{
/* Get the SID and it's length */
Sid = SrcSidAndAttributes[i].Sid;
SidLength = RtlLengthRequiredSid(Sid->SubAuthorityCount);
/* Copy attributes */
SidAndAttributes[i].Attributes = SrcSidAndAttributes[i].Attributes;
/* Copy the SID to the current destination address */
SidAndAttributes[i].Sid = (PSID)CurrentDest;
RtlCopyMemory(CurrentDest, SrcSidAndAttributes[i].Sid, SidLength);
/* Update the current destination address */
CurrentDest += ALIGN_UP_BY(SidLength, sizeof(ULONG));
}
}
Cleanup:
/* Check for failure */
if (!NT_SUCCESS(Status))
{
/* Check if we allocated a new array */
if ((SidAndAttributes != AllocatedMem) && (SidAndAttributes != NULL))
{
/* Free the array */
ExFreePoolWithTag(SidAndAttributes, TAG_SID_AND_ATTRIBUTES);
}
/* Set returned address to NULL */
*CapturedSidAndAttributes = NULL;
}
/* Free the temporary validation array */
if ((PreviousMode != KernelMode) && (ValidateArray != NULL))
{
ExFreePoolWithTag(ValidateArray, TAG_SID_VALIDATE);
}
return Status;
}
/**
* @brief
* Releases a captured SID with attributes.
*
* @param[in] CapturedSidAndAttributes
* The captured SID with attributes to be released.
*
* @param[in] AccessMode
* Processor access level mode.
*
* @param[in] CaptureIfKernel
* If set to TRUE, the releasing is done within the kernel.
* Otherwise the releasing is done in a kernel mode driver.
*
* @return
* Nothing.
*/
VOID
NTAPI
SeReleaseSidAndAttributesArray(
_In_ _Post_invalid_ PSID_AND_ATTRIBUTES CapturedSidAndAttributes,
_In_ KPROCESSOR_MODE AccessMode,
_In_ BOOLEAN CaptureIfKernel)
{
PAGED_CODE();
if ((CapturedSidAndAttributes != NULL) &&
((AccessMode != KernelMode) || CaptureIfKernel))
{
ExFreePoolWithTag(CapturedSidAndAttributes, TAG_SID_AND_ATTRIBUTES);
}
}
/* EOF */