SeSetSecurityDescriptorInfoEx function (ntifs.h)

Article
09/27/2023

The SeSetSecurityDescriptorInfoEx routine modifies an object's security descriptor and specifies whether the object supports automatic inheritance of access control entries (ACE).

Syntax

NTSTATUS SeSetSecurityDescriptorInfoEx(
  [in, optional] PVOID                 Object,
  [in]           PSECURITY_INFORMATION SecurityInformation,
                 PSECURITY_DESCRIPTOR  ModificationDescriptor,
  [in, out]      PSECURITY_DESCRIPTOR  *ObjectsSecurityDescriptor,
  [in]           ULONG                 AutoInheritFlags,
  [in]           POOL_TYPE             PoolType,
  [in]           PGENERIC_MAPPING      GenericMapping
);

Parameters

[in, optional] Object

Pointer to the object whose security descriptor is to be modified. This is used to update security quota information.

[in] SecurityInformation

Pointer to a value specifying which security information is to be set. Can be a combination of one or more of the following.

Value	Meaning
DACL_SECURITY_INFORMATION	Indicates the discretionary access control list (DACL) of the object is being set. Requires WRITE_DAC access.
GROUP_SECURITY_INFORMATION	Indicates the primary group identifier of the object is being set. Requires WRITE_OWNER access.
OWNER_SECURITY_INFORMATION	Indicates the owner identifier of the object is being set. Requires WRITE_OWNER access.
SACL_SECURITY_INFORMATION	Indicates the system ACL (SACL) of the object is being set. Requires ACCESS_SYSTEM_SECURITY access.

ModificationDescriptor

The input security descriptor to be applied to the object. The caller of this routine is expected to probe and capture the passed security descriptor before calling, and to release it after calling.

[in, out] ObjectsSecurityDescriptor

Pointer to a pointer to the object's security descriptor. The security descriptor must be in self-relative format. This structure must be deallocated by the caller.

[in] AutoInheritFlags

Bitmask that controls automatic inheritance of ACEs. Set to the logical OR of one or more of the following bit flags:

Security Information Flags	Meaning
SEF_DACL_AUTO_INHERIT	If this flag is set, the DACL is treated as an auto-inherit DACL and is processed as described in the following Remarks section. This bit is ignored if DACL_SECURITY_INFORMATION is not set in the SecurityInformation parameter.
SEF_SACL_AUTO_INHERIT	If this flag is set, the SACL is treated as an auto-inherit SACL and is processed as described in the following Remarks section. This bit is ignored if SACL_SECURITY_INFORMATION is not set in the SecurityInformation parameter.

[in] PoolType

Specifies the pool type to use when allocating a new security descriptor, which can be one of the following:

NonPagedPool
PagedPool
NonPagedPoolCacheAligned
PagedPoolCacheAligned

Usually, a caller specifies PagedPool, or else NonPagedPool if the buffer will be accessed at IRQL >= DISPATCH_LEVEL or in an arbitrary thread context.

The NonPagedPoolMustSucceed and NonPagedPoolCacheAlignedMustS pool types are obsolete and should no longer be used.

[in] GenericMapping

Pointer to a GENERIC_MAPPING structure that specifies the mapping of generic to specific and standard access types for the object being accessed. This mapping structure is expected to be safe to access (that is, captured if necessary) prior to be passed to this routine.

Return value

Return code	Description
STATUS_SUCCESS	The object's security descriptor was successfully modified.
STATUS_BAD_DESCRIPTOR_FORMAT	The provided object's security descriptor was not in self-relative format.
STATUS_NO_SECURITY_ON_OBJECT	The object does not have a security descriptor.

Remarks

If the AutoInheritFlags parameter is zero, the effect of calling SeSetSecurityDescriptorInfoEx is the same as that of calling SeSetSecurityDescriptorInfo.

If AutoInheritFlags specifies the SEF_DACL_AUTO_INHERIT bit, SeSetSecurityDescriptorInfoEx applies the following rules to the DACL to create the new security descriptor from the current descriptor:

If the SE_DACL_PROTECTED flag is not set in the control bits of the either the current security descriptor or the input SecurityDescriptor, SeSetSecurityDescriptorInfoEx constructs the output security descriptor from the inherited ACEs of the current security descriptor and noninherited ACEs of SecurityDescriptor. That is, it is impossible to change an inherited ACE by changing the ACL on an object. This behavior preserves the inherited ACEs as they were inherited from the parent container.
If SE_DACL_PROTECTED is set in the input SecurityDescriptor, the current security descriptor is ignored. The output security descriptor is built as a copy of the input SecurityDescriptor with any INHERITED_ACE bits turned off.

Ideally an ACL editor should turn off the INHERITED_ACE bits indicating to its caller that the ACEs inherited from the object's parent are now being explicitly set on the object.

If SE_DACL_PROTECTED is set in the current security descriptor and not in the SecurityDescriptor, the current security descriptor is ignored. The output security descriptor is built as a copy of the SecurityDescriptor. It is the caller's responsibility to ensure that the correct ACEs have the INHERITED_ACE bit turned on.

If AutoInheritFlags specifies the SEF_SACL_AUTO_INHERIT bit, SeSetSecurityDescriptorInfoEx applies similar rules to the new SACL.

For more information about access control and ACE inheritance, see the Security section of the Microsoft Windows SDK documentation.

Requirements

Requirement	Value
Minimum supported client	Windows 2000
Target Platform	Universal
Header	ntifs.h (include Ntifs.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe
IRQL	PASSIVE_LEVEL