NTSTATUS
NTAPI
NpCommonSetSecurityInfo(IN PDEVICE_OBJECT DeviceObject,
IN PIRP Irp)
{
NODE_TYPE_CODE NodeTypeCode;
PIO_STACK_LOCATION IoStack;
NTSTATUS Status;
PNP_FCB Fcb;
PNP_CCB Ccb;
ULONG NamedPipeEnd;
PSECURITY_DESCRIPTOR OldSecurityDescriptor;
PSECURITY_DESCRIPTOR TempSecurityDescriptor;
PSECURITY_DESCRIPTOR NewSecurityDescriptor;
PAGED_CODE();
IoStack = IoGetCurrentIrpStackLocation(Irp);
NodeTypeCode = NpDecodeFileObject(IoStack->FileObject,
(PVOID*)&Fcb,
&Ccb,
&NamedPipeEnd);
if (!NodeTypeCode) return STATUS_PIPE_DISCONNECTED;
if (NodeTypeCode != NPFS_NTC_CCB) return STATUS_INVALID_PARAMETER;
OldSecurityDescriptor = TempSecurityDescriptor = Fcb->SecurityDescriptor;
Status = SeSetSecurityDescriptorInfo(NULL,
&IoStack->Parameters.SetSecurity.SecurityInformation,
IoStack->Parameters.SetSecurity.SecurityDescriptor,
&TempSecurityDescriptor,
TRUE,
IoGetFileObjectGenericMapping());
if (!NT_SUCCESS(Status)) return Status;
Status = ObLogSecurityDescriptor(TempSecurityDescriptor, &NewSecurityDescriptor, 1);
ASSERT(TempSecurityDescriptor != OldSecurityDescriptor);
ExFreePoolWithTag(TempSecurityDescriptor, 0);
if (!NT_SUCCESS(Status)) return Status;
Fcb->SecurityDescriptor = NewSecurityDescriptor;
ObDereferenceSecurityDescriptor(OldSecurityDescriptor, 1);
return Status;
}
NTSTATUS
NTAPI
ObAssignObjectSecurityDescriptor(IN PVOID Object,
IN PSECURITY_DESCRIPTOR SecurityDescriptor OPTIONAL,
IN POOL_TYPE PoolType)
{
POBJECT_HEADER ObjectHeader;
NTSTATUS Status;
PSECURITY_DESCRIPTOR NewSd;
PEX_FAST_REF FastRef;
PAGED_CODE();
/* Get the object header */
ObjectHeader = OBJECT_TO_OBJECT_HEADER(Object);
FastRef = (PEX_FAST_REF)&ObjectHeader->SecurityDescriptor;
if (!SecurityDescriptor)
{
/* Nothing to assign */
ExInitializeFastReference(FastRef, NULL);
return STATUS_SUCCESS;
}
/* Add it to our internal cache */
Status = ObLogSecurityDescriptor(SecurityDescriptor,
&NewSd,
MAX_FAST_REFS + 1);
if (NT_SUCCESS(Status))
{
/* Free the old copy */
ExFreePoolWithTag(SecurityDescriptor, TAG_SD);
/* Set the new pointer */
ASSERT(NewSd);
ExInitializeFastReference(FastRef, NewSd);
}
/* Return status */
return Status;
}
NTSTATUS
NTAPI
ObSetSecurityDescriptorInfo(IN PVOID Object,
IN PSECURITY_INFORMATION SecurityInformation,
IN OUT PSECURITY_DESCRIPTOR SecurityDescriptor,
IN OUT PSECURITY_DESCRIPTOR *OutputSecurityDescriptor,
IN POOL_TYPE PoolType,
IN PGENERIC_MAPPING GenericMapping)
{
NTSTATUS Status;
POBJECT_HEADER ObjectHeader;
PSECURITY_DESCRIPTOR OldDescriptor, NewDescriptor, CachedDescriptor;
PEX_FAST_REF FastRef;
EX_FAST_REF OldValue;
ULONG_PTR Count;
PAGED_CODE();
/* Get the object header */
ObjectHeader = OBJECT_TO_OBJECT_HEADER(Object);
while (TRUE)
{
/* Reference the old descriptor */
OldDescriptor = ObpReferenceSecurityDescriptor(ObjectHeader);
NewDescriptor = OldDescriptor;
/* Set the SD information */
Status = SeSetSecurityDescriptorInfo(Object,
SecurityInformation,
SecurityDescriptor,
&NewDescriptor,
PoolType,
GenericMapping);
if (NT_SUCCESS(Status))
{
/* Now add this to the cache */
Status = ObLogSecurityDescriptor(NewDescriptor,
&CachedDescriptor,
MAX_FAST_REFS + 1);
/* Let go of our uncached copy */
ExFreePool(NewDescriptor);
/* Check for success */
if (NT_SUCCESS(Status))
{
/* Do the swap */
FastRef = (PEX_FAST_REF)OutputSecurityDescriptor;
OldValue = ExCompareSwapFastReference(FastRef,
CachedDescriptor,
OldDescriptor);
/* Get the security descriptor */
SecurityDescriptor = ExGetObjectFastReference(OldValue);
Count = ExGetCountFastReference(OldValue);
/* Make sure the swap worked */
if (SecurityDescriptor == OldDescriptor)
{
/* Flush waiters */
ObpAcquireObjectLock(ObjectHeader);
ObpReleaseObjectLock(ObjectHeader);
/* And dereference the old one */
ObDereferenceSecurityDescriptor(OldDescriptor, Count + 2);
break;
}
else
{
/* Someone changed it behind our back -- try again */
ObDereferenceSecurityDescriptor(OldDescriptor, 1);
ObDereferenceSecurityDescriptor(CachedDescriptor,
MAX_FAST_REFS + 1);
}
}
else
{
/* We failed, dereference the old one */
ObDereferenceSecurityDescriptor(OldDescriptor, 1);
break;
}
}
else
{
/* We failed, dereference the old one */
if (OldDescriptor) ObDereferenceSecurityDescriptor(OldDescriptor, 1);
break;
}
}
/* Return status */
return Status;
}
