windows-nt-4.0/private/ntos/ob/obinsert.c

/*++

Copyright (c) 1989  Microsoft Corporation

Module Name:

    obinsert.c

Abstract:

    Object instantiation API

Author:

    Steve Wood (stevewo) 31-Mar-1989

Revision History:

--*/

#include "obp.h"

#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE,ObInsertObject)
#endif

NTSTATUS
ObInsertObject(
    IN PVOID Object,
    IN PACCESS_STATE AccessState OPTIONAL,
    IN ACCESS_MASK DesiredAccess OPTIONAL,
    IN ULONG ObjectPointerBias,
    OUT PVOID *NewObject OPTIONAL,
    OUT PHANDLE Handle
    )

/*++

Routine Description:

    description-of-function.

    The Object header includes a pointer to a SecurityDescriptor passed in
    an object creation call.  This SecurityDescriptor is not assumed to have
    been captured.  This routine is responsible for making an appropriate
    SecurityDescriptor and removing the reference in the object header.

Arguments:

    argument-name - Supplies | Returns description of argument.
    .
    .

Return Value:

    return-value - Description of conditions needed to return value. - or -
    None.

--*/


{

    POBJECT_CREATE_INFORMATION ObjectCreateInfo;
    POBJECT_HEADER ObjectHeader;
    PUNICODE_STRING ObjectName;
    POBJECT_TYPE ObjectType;
    POBJECT_HEADER_NAME_INFO NameInfo;
    PSECURITY_DESCRIPTOR ParentDescriptor = NULL;
    PVOID InsertObject;
    HANDLE NewHandle;
    BOOLEAN DirectoryLocked;
    OB_OPEN_REASON OpenReason;
    NTSTATUS Status = STATUS_SUCCESS;
    ACCESS_STATE LocalAccessState;
    AUX_ACCESS_DATA AuxData;
    BOOLEAN SecurityDescriptorAllocated;
    KPROCESSOR_MODE PreviousMode;
    NTSTATUS ReturnStatus;

    PAGED_CODE();

    ObpValidateIrql("ObInsertObject");

    //
    // Get the address of the object header, the object create information,
    // the object type, and the address of the object name descriptor, if
    // specified.
    //

    ObjectHeader = OBJECT_TO_OBJECT_HEADER(Object);

#if DBG

    if ((ObjectHeader->Flags & OB_FLAG_NEW_OBJECT) == 0) {
        KdPrint(("OB: Attempting to insert existing object %08x\n", Object));
        KdBreakPoint();
        ObDereferenceObject(Object);
        return STATUS_INVALID_PARAMETER;
    }

#endif

    ObjectCreateInfo = ObjectHeader->ObjectCreateInfo;
    ObjectType = ObjectHeader->Type;
    NameInfo = OBJECT_HEADER_TO_NAME_INFO(ObjectHeader);
    ObjectName = NULL;
    if ((NameInfo != NULL) && (NameInfo->Name.Buffer != NULL)) {
        ObjectName = &NameInfo->Name;
    }

    //
    // If security checks are not required and an object name is not
    // specified, then insert an unnamed object.
    //

    PreviousMode = KeGetPreviousMode();
    if (!ObjectType->TypeInfo.SecurityRequired && (ObjectName == NULL)) {
        ObjectHeader->ObjectCreateInfo = NULL;
        *Handle = NULL;
        Status = ObpCreateUnnamedHandle(Object,
                                        DesiredAccess,
                                        1 + ObjectPointerBias,
                                        ObjectCreateInfo->Attributes,
                                        PreviousMode,
                                        NewObject,
                                        Handle);

        //
        // Free the object creation information and dereference the object.
        //

        ObpFreeObjectCreateInformation(ObjectCreateInfo);
        ObDereferenceObject(Object);
        return Status;
    }

    //
    // The object is either named or requires full security checks.
    //

    if (!ARGUMENT_PRESENT(AccessState)) {
        AccessState = &LocalAccessState;
        Status = SeCreateAccessState(&LocalAccessState,
                                          &AuxData,
                                          DesiredAccess,
                                          &ObjectType->TypeInfo.GenericMapping);

        if (!NT_SUCCESS(Status)) {
            ObDereferenceObject(Object);
            return Status;
        }
    }

    AccessState->SecurityDescriptor = ObjectCreateInfo->SecurityDescriptor;
    Status = ObpValidateAccessMask( AccessState );
    if (!NT_SUCCESS( Status )) {
        ObDereferenceObject(Object);
        return( Status );
    }

    DirectoryLocked = FALSE;
    InsertObject = Object;
    OpenReason = ObCreateHandle;
    if (ObjectName != NULL) {
        Status = ObpLookupObjectName(ObjectCreateInfo->RootDirectory,
                                     ObjectName,
                                     ObjectCreateInfo->Attributes,
                                     ObjectType,
                                     (KPROCESSOR_MODE)(ObjectHeader->Flags & OB_FLAG_KERNEL_OBJECT
                                                           ? KernelMode : UserMode),
                                     ObjectCreateInfo->ParseContext,
                                     ObjectCreateInfo->SecurityQos,
                                     Object,
                                     AccessState,
                                     &DirectoryLocked,
                                     &InsertObject);

        if (NT_SUCCESS(Status) &&
            (InsertObject != NULL) &&
            (InsertObject != Object)) {
            OpenReason = ObOpenHandle;
            if (ObjectCreateInfo->Attributes & OBJ_OPENIF) {
                if (ObjectType != OBJECT_TO_OBJECT_HEADER(InsertObject)->Type) {
                    Status = STATUS_OBJECT_TYPE_MISMATCH;

                } else {
                    Status = STATUS_OBJECT_NAME_EXISTS;     // Warning only
                }

            } else {
                Status = STATUS_OBJECT_NAME_COLLISION;
            }
        }

        if (!NT_SUCCESS( Status )) {

            if (DirectoryLocked) {
                ObpLeaveRootDirectoryMutex();
            }

            ObDereferenceObject( Object );

            //
            // Free security information if we allocated it
            //

            if (AccessState == &LocalAccessState) {
                SeDeleteAccessState( AccessState );
            }

            return( Status );
        }
    }

    //
    // If we are creating a new object, then we need assign security
    // to it.  A pointer to the captured caller-proposed security
    // descriptor is contained in the AccessState structure.  The
    // SecurityDescriptor field in the object header must point to
    // the final security descriptor, or to NULL if no security is
    // to be assigned to the object.
    //

    if (InsertObject == Object) {

        //
        // Only the following objects have security descriptors:
        //
        //       - Named Objects
        //       - Unnamed objects whose object-type information explicitly
        //         indicates a security descriptor is required.
        //

        if (ObjectName != NULL || ObjectType->TypeInfo.SecurityRequired) {

            //
            // Get the parent's descriptor, if there is one...
            //

            if (NameInfo != NULL && NameInfo->Directory != NULL) {

                //
                // This will allocate a block of memory and copy
                // the parent's security descriptor into it, and
                // return the pointer to the block.
                //
                // Call ObReleaseObjectSecurity to free up this
                // memory.
                //

                ObGetObjectSecurity( NameInfo->Directory,
                                     &ParentDescriptor,
                                     &SecurityDescriptorAllocated
                                   );
                }

            //
            // Take the captured security descriptor in the AccessState,
            // put it into the proper format, and call the object's
            // security method to assign the new security descriptor to
            // the new object.
            //

            Status = ObAssignSecurity( AccessState,
                                       ParentDescriptor,
                                       Object,
                                       ObjectType
                                     );

            if (ParentDescriptor != NULL) {
                ObReleaseObjectSecurity( ParentDescriptor,
                                         SecurityDescriptorAllocated
                                       );
                }
            else
            if (NT_SUCCESS( Status )) {
                SeReleaseSecurityDescriptor(
                                   ObjectCreateInfo->SecurityDescriptor,
                                   ObjectCreateInfo->ProbeMode,
                                   TRUE
                                   );
                ObjectCreateInfo->SecurityDescriptor = NULL;
                AccessState->SecurityDescriptor = NULL;
                }
            }

        if (!NT_SUCCESS( Status )) {

            //
            // The attempt to assign the security descriptor to
            // the object failed.
            //


            if (DirectoryLocked) {
                ObpDeleteDirectoryEntry( NameInfo->Directory );
                ObpLeaveRootDirectoryMutex();
                }

            //
            // Make the name reference go away if an error.
            //

            if (ObjectName != NULL) {
                ObpDeleteNameCheck( Object, FALSE );
                }

            ObDereferenceObject( Object );

            //
            // Free security information if we allocated it
            //

            if (AccessState == &LocalAccessState) {
                SeDeleteAccessState( AccessState );
                }

            return( Status );
            }
        }

    ReturnStatus = Status;
    ObjectHeader->ObjectCreateInfo = NULL;
    Status = ObpCreateHandle( OpenReason,
                              InsertObject,
                              NULL,
                              AccessState,
                              1 + ObjectPointerBias,
                              ObjectCreateInfo->Attributes,
                              DirectoryLocked,
                              PreviousMode,
                              NewObject,
                              &NewHandle
                             );
    ObpFreeObjectCreateInformation( ObjectCreateInfo );

    //
    // If the insertion failed, the following dereference will cause
    // the newly created object to be and deallocated.
    //

    if (!NT_SUCCESS( Status )) {
        //
        // Make the name reference go away if an error.
        //

        if (ObjectName != NULL) {
            ObpDeleteNameCheck( Object, FALSE );
            }
        }

    ObDereferenceObject( Object );
    if (NT_SUCCESS( Status )) {
        *Handle = NewHandle;
        }
    else {
        *Handle = NULL;
        ReturnStatus = Status;
        }

    //
    // Free security information if we allocated it
    //

    if (AccessState == &LocalAccessState) {
        SeDeleteAccessState( AccessState );
        }

    return( ReturnStatus );
}