windows-xp/Source/XPSP1/NT/base/fs/srv/fspinit.c

/*++

Copyright (c) 1989  Microsoft Corporation

Module Name:

    fspinit.c

Abstract:

    This module implements the initialization phase of the LAN Manager
    server File System Process.

Author:

    Chuck Lenzmeier (chuckl)    22-Sep-1989
    David Treadwell (davidtr)

Revision History:

--*/

#include "precomp.h"
#include "fspinit.tmh"
#pragma hdrstop

#define BugCheckFileId SRV_FILE_FSPINIT

//
// Forward declarations.
//

PIRP
DequeueConfigurationIrp (
    VOID
    );

STATIC
NTSTATUS
InitializeServer (
    VOID
    );

STATIC
NTSTATUS
TerminateServer (
    VOID
    );

VOID
SrvFreeRegTables (
    VOID
    );

VOID
SrvGetRegTables (
    VOID
    );

#if SRVNTVERCHK
VOID
SrvGetRegClientNumber (
    VOID
    );
#endif

VOID
StartQueueDepthComputations(
    PWORK_QUEUE queue
    );

VOID
StopQueueDepthComputations(
    PWORK_QUEUE queue
    );

VOID
ComputeAvgQueueDepth (
    IN PKDPC Dpc,
    IN PVOID DeferredContext,
    IN PVOID SystemArgument1,
    IN PVOID SystemArgument2
    );

BOOLEAN
GenerateCrcTable();

BOOLEAN
CleanupCrcTable();

#ifdef ALLOC_PRAGMA
#pragma alloc_text( PAGE, SrvConfigurationThread )
#pragma alloc_text( PAGE, InitializeServer )
#pragma alloc_text( PAGE, TerminateServer )
#pragma alloc_text( PAGE, SrvFreeRegTables )
#pragma alloc_text( PAGE, SrvGetRegTables )
#if SRVNTVERCHK
#pragma alloc_text( PAGE, SrvGetRegClientNumber )
#endif
#pragma alloc_text( PAGE, DequeueConfigurationIrp )
#pragma alloc_text( PAGE, StartQueueDepthComputations )
#endif


VOID
SrvConfigurationThread (
    IN PDEVICE_OBJECT pDevice,
    IN PIO_WORKITEM pWorkItem
    )

/*++

Routine Description:

    This routine processes configuration IRPs.

Arguments:

    None.

Return Value:

    None.

--*/

{
    NTSTATUS status;
    PIRP irp;
    PIO_STACK_LOCATION irpSp;
    ULONG code;

    PAGED_CODE( );

    IF_DEBUG(FSP1) KdPrint(( "SrvConfigurationThread entered\n" ));

    //
    // Loop processing requests.
    //

    while ( TRUE ) {

        irp = DequeueConfigurationIrp( );

        if ( irp == NULL ) break;

        ASSERT( (LONG)SrvConfigurationIrpsInProgress >= 1 );

        //
        // Get the IRP stack pointer.
        //

        irpSp = IoGetCurrentIrpStackLocation( irp );

        if( irpSp->MajorFunction == IRP_MJ_CLOSE ) {

            //
            // If the dispatcher routed this irp here, it means
            //  that we unexpectededly got the last handle close without
            //  having gotten cleanly terminated first. Ok, so we should
            //  shut ourselves down, since we can't sensibly run without
            //  our usermode counterpart.
            //

            ACQUIRE_LOCK( &SrvStartupShutdownLock );
            status = TerminateServer();
            RELEASE_LOCK( &SrvStartupShutdownLock );

        } else {

            ASSERT( irpSp->MajorFunction == IRP_MJ_FILE_SYSTEM_CONTROL );

            try {

                //
                // Dispatch on the FsControlCode.
                //

                code = irpSp->Parameters.FileSystemControl.FsControlCode;

                switch ( code ) {

                case FSCTL_SRV_STARTUP:
                    ACQUIRE_LOCK( &SrvStartupShutdownLock );

                    status = InitializeServer();

                    if ( !NT_SUCCESS(status) ) {

                        //
                        // Terminate the server FSP.
                        //
                        (void)TerminateServer();

                    }

                    RELEASE_LOCK( &SrvStartupShutdownLock );

                    break;

                case FSCTL_SRV_SHUTDOWN:

                    ACQUIRE_LOCK( &SrvStartupShutdownLock );
                    status = TerminateServer();
                    RELEASE_LOCK( &SrvStartupShutdownLock );

                    //
                    // If there is more than one handle open to the server
                    // device (i.e., any handles other than the server service's
                    // handle), return a special status code to the caller (who
                    // should be the server service).  This tells the caller to
                    // NOT unload the driver, in order prevent weird situations
                    // where the driver is sort of unloaded, so it can't be used
                    // but also can't be reloaded, thus preventing the server
                    // from being restarted.
                    //

                    if( NT_SUCCESS( status ) && SrvOpenCount != 1 ) {
                        status = STATUS_SERVER_HAS_OPEN_HANDLES;
                    }

                    break;

                case FSCTL_SRV_REGISTRY_CHANGE:
                    //
                    // The Parameters section of the server service registry has changed.
                    // That's likely due to somebody changing the Null Session pipe or
                    //  share lists.  Pick up the new settings.
                    //
                    ACQUIRE_LOCK( &SrvConfigurationLock );

                    SrvFreeRegTables();
                    SrvGetRegTables();
    #if SRVNTVERCHK
                    SrvGetRegClientNumber();
    #endif

                    RELEASE_LOCK( &SrvConfigurationLock );

                    status = STATUS_SUCCESS;

                    break;

                case FSCTL_SRV_BEGIN_PNP_NOTIFICATIONS:
                    //
                    // If somebody tries to shut down the server while
                    //  we are registering our handlers, block them until
                    //  we are finished.
                    //
                    ACQUIRE_LOCK( &SrvStartupShutdownLock );

                    {
                        TDI_CLIENT_INTERFACE_INFO ClientInterfaceInfo;

                        RtlZeroMemory(&ClientInterfaceInfo, sizeof(TDI_CLIENT_INTERFACE_INFO));

                        ClientInterfaceInfo.MajorTdiVersion = 2;
                        ClientInterfaceInfo.MinorTdiVersion = 0;
                        ClientInterfaceInfo.ClientName = &StrRegSrvPnpClientName;
                        ClientInterfaceInfo.BindingHandler = SrvPnpBindingHandler;
                        ClientInterfaceInfo.PnPPowerHandler = SrvPnpPowerHandler;


                        status = TdiRegisterPnPHandlers(
                                                        &ClientInterfaceInfo,
                                                        sizeof( ClientInterfaceInfo ),
                                                        &SrvTdiNotificationHandle
                                                        );

                        if (status != STATUS_SUCCESS) {
                            SrvTdiNotificationHandle = NULL;
                        }
                    }

                    RELEASE_LOCK( &SrvStartupShutdownLock );

                    if( !NT_SUCCESS( status ) ) {

                            IF_DEBUG( PNP ) {
                                KdPrint(("TdiRegisterNotificationHandler: status %X\n", status ));
                            }

                            SrvLogServiceFailure( SRV_SVC_PNP_TDI_NOTIFICATION, status );
                    }

                    //
                    // Allow the transports to begin receiving connections
                    //
                    SrvCompletedPNPRegistration = TRUE;

                    break;

                case FSCTL_SRV_XACTSRV_CONNECT:
                {
                    ANSI_STRING ansiPortName;
                    UNICODE_STRING portName;

                    IF_DEBUG(XACTSRV) {
                        KdPrint(( "SrvFspConfigurationThread: XACTSRV FSCTL "
                                  "received.\n" ));
                    }

                    ansiPortName.Buffer = irp->AssociatedIrp.SystemBuffer;
                    ansiPortName.Length =
                        (USHORT)irpSp->Parameters.FileSystemControl.InputBufferLength;

                    status = RtlAnsiStringToUnicodeString(
                                 &portName,
                                 &ansiPortName,
                                 TRUE
                                 );
                    if ( NT_SUCCESS(status) ) {
                        status = SrvXsConnect( &portName );
                        RtlFreeUnicodeString( &portName );
                    }

                    break;
                }

                case FSCTL_SRV_XACTSRV_DISCONNECT:
                {
                    //
                    // This is now obsolete
                    //
                    status = STATUS_SUCCESS;

                    break;
                }

                case FSCTL_SRV_START_SMBTRACE:
                {
                    KdPrint(( "SrvFspConfigurationThread: START_SMBTRACE FSCTL "
                                                  "received.\n" ));

                    //
                    // Initialize the SmbTrace related events.
                    //

                    status = SmbTraceInitialize( SMBTRACE_SERVER );

                    if ( NT_SUCCESS(status) ) {

                        //
                        // Create shared memory, create events, start SmbTrace thread,
                        // and indicate that this is the server.
                        //

                        status = SmbTraceStart(
                                    irpSp->Parameters.FileSystemControl.InputBufferLength,
                                    irpSp->Parameters.FileSystemControl.OutputBufferLength,
                                    irp->AssociatedIrp.SystemBuffer,
                                    irpSp->FileObject,
                                    SMBTRACE_SERVER
                                    );

                        if ( NT_SUCCESS(status) ) {

                            //
                            // Record the length of the return information, which is
                            // simply the length of the output buffer, validated by
                            // SmbTraceStart.
                            //

                            irp->IoStatus.Information =
                                    irpSp->Parameters.FileSystemControl.OutputBufferLength;

                        }

                    }

                    break;
                }

                case FSCTL_SRV_SEND_DATAGRAM:
                {
                    ANSI_STRING domain;
                    ULONG buffer1Length;
                    PVOID buffer2;
                    PSERVER_REQUEST_PACKET srp;

                    buffer1Length = ALIGN_UP(
                        irpSp->Parameters.FileSystemControl.InputBufferLength,
                        PVOID );

                    buffer2 = (PCHAR)irp->AssociatedIrp.SystemBuffer + buffer1Length;

                    srp = irp->AssociatedIrp.SystemBuffer;

                    //
                    // Send the second-class mailslot in Buffer2 to the domain
                    // specified in srp->Name1 on transport specified by srp->Name2.
                    //

                    domain = *((PANSI_STRING) &srp->Name1);

                    status = SrvSendDatagram(
                                 &domain,
                                 ( srp->Name2.Length != 0 ? &srp->Name2 : NULL ),
                                 buffer2,
                                 irpSp->Parameters.FileSystemControl.OutputBufferLength
                                 );

                    ExFreePool( irp->AssociatedIrp.SystemBuffer );
                    DEBUG irp->AssociatedIrp.SystemBuffer = NULL;

                    break;
                }

                case FSCTL_SRV_NET_FILE_CLOSE:
                case FSCTL_SRV_NET_SERVER_XPORT_ADD:
                case FSCTL_SRV_NET_SERVER_XPORT_DEL:
                case FSCTL_SRV_NET_SESSION_DEL:
                case FSCTL_SRV_NET_SHARE_ADD:
                case FSCTL_SRV_NET_SHARE_DEL:
                {
                    PSERVER_REQUEST_PACKET srp;
                    PVOID buffer2;
                    ULONG buffer1Length;
                    ULONG buffer2Length;

                    //
                    // These APIs are handled in the server FSP because they
                    // open or close FSP handles.
                    //

                    ACQUIRE_LOCK_SHARED( &SrvConfigurationLock );
                    if( SrvFspTransitioning == TRUE && SrvFspActive == TRUE ) {
                        //
                        // The server is coming down.  Do not allow these
                        //  irps to continue.
                        //
                        RELEASE_LOCK( &SrvConfigurationLock );
                        status = STATUS_SERVER_NOT_STARTED;
                        break;
                    }
                    RELEASE_LOCK( &SrvConfigurationLock );

                    //
                    // Get the server request packet and secondary input buffer
                    // pointers.
                    //

                    buffer1Length = ALIGN_UP(
                        irpSp->Parameters.FileSystemControl.InputBufferLength,
                        PVOID );

                    buffer2Length =
                        irpSp->Parameters.FileSystemControl.OutputBufferLength;

                    srp = irp->AssociatedIrp.SystemBuffer;
                    buffer2 = (PCHAR)srp + buffer1Length;

                    //
                    // Dispatch the API request to the appripriate API processing
                    // routine.
                    //

                    status = SrvApiDispatchTable[ SRV_API_INDEX(code) ](
                                 srp,
                                 buffer2,
                                 buffer2Length
                                 );

                    break;
                }

                default:
                    IF_DEBUG(ERRORS) {
                        KdPrint((
                            "SrvFspConfigurationThread: Invalid control code %lx\n",
                            irpSp->Parameters.FileSystemControl.FsControlCode ));
                    }

                    status = STATUS_INVALID_PARAMETER;
                }
            } except(EXCEPTION_EXECUTE_HANDLER) {
                status = GetExceptionCode();
            }
        }

        //
        // Make sure we're still at PASSIVE_LEVEL
        //
        if( KeGetCurrentIrql() > PASSIVE_LEVEL )
        {
            goto bad_irql_failure;
        }

        //
        // Complete the IO request.
        //

        irp->IoStatus.Status = status;
        IoCompleteRequest( irp, 2 );

        //
        // Make sure we're still at PASSIVE_LEVEL
        //
        if( KeGetCurrentIrql() > PASSIVE_LEVEL )
        {
            goto bad_irql_failure;
        }

        ASSERT( (LONG)SrvConfigurationIrpsInProgress >= 0 );

        // Make sure we don't continue if there are no IRP's left
        if( InterlockedDecrement( (PLONG)&SrvConfigurationIrpsInProgress ) == 0 )
        {
            break;
        }
    }

    IoFreeWorkItem( pWorkItem );

    return;

bad_irql_failure:

    DbgPrint( "ERROR: SrvConfigurationThread returning at >PASSIVE level\n" );
    DbgBreakPoint();

    IoFreeWorkItem( pWorkItem );

    return;

} // SrvConfigurationThread


PIRP
DequeueConfigurationIrp (
    VOID
    )

/*++

Routine Description:

    This routine retrieves an IRP from the configuration work queue.

Arguments:

    None.

Return Value:

    PIRP - Pointer to configuration IRP, or NULL.

--*/

{
    PLIST_ENTRY listEntry;
    PIRP irp;

    PAGED_CODE( );

    //
    // Take an IRP off the configuration queue.
    //

    ACQUIRE_LOCK( &SrvConfigurationLock );

    listEntry = RemoveHeadList( &SrvConfigurationWorkQueue );

    if ( listEntry == &SrvConfigurationWorkQueue ) {

        //
        // The queue is empty.
        //

        irp = NULL;

    } else {

        irp = CONTAINING_RECORD( listEntry, IRP, Tail.Overlay.ListEntry );

    }

    RELEASE_LOCK( &SrvConfigurationLock );

    return irp;

} // DequeueConfigurationIrp


STATIC
NTSTATUS
InitializeServer (
    VOID
    )

/*++

Routine Description:

    This routine initializes the server.

Arguments:

    None.

Return Value:

    None.

--*/

{
    NTSTATUS status;
    CLONG i;
    PWORK_CONTEXT workContext;
    OBJECT_ATTRIBUTES objectAttributes;
    IO_STATUS_BLOCK ioStatusBlock;
    OBJECT_HANDLE_INFORMATION handleInformation;
    PSID AdminSid;
    PSID AnonymousSid;
    PACL Acl;
    ULONG length;
    SID_IDENTIFIER_AUTHORITY BuiltinAuthority = SECURITY_NT_AUTHORITY;
    PWORK_QUEUE queue;
    HANDLE handle;
    UNICODE_STRING string;

    PAGED_CODE();

    //
    // If running as an Advanced Server, lock all pageable server code.
    //

    if ( SrvProductTypeServer ) {
        for ( i = 0; i < SRV_CODE_SECTION_MAX; i++ ) {
            SrvReferenceUnlockableCodeSection( i );
        }
    }

    //
    // Initialize the server start time
    //

    KeQuerySystemTime( &SrvStatistics.StatisticsStartTime );

    //
    // Get actual alert service name using the display name found in the
    // registry.
    //

    SrvGetAlertServiceName( );

    //
    // Get the Os versions strings.
    //

    SrvGetOsVersionString( );

    //
    // Get the list of null session pipes and shares
    //
    SrvGetRegTables( );

#if SRVNTVERCHK
    SrvGetRegClientNumber();
#endif

#if MULTIPROCESSOR
    //
    // Allocate and init the nonblocking work queues, paying attention to cache lines
    //
    i = SrvNumberOfProcessors * sizeof( *SrvWorkQueues );
    i += CACHE_LINE_SIZE;
    SrvWorkQueuesBase = ALLOCATE_NONPAGED_POOL( i, BlockTypeWorkQueue );

    if( SrvWorkQueuesBase == NULL ) {
         return STATUS_INSUFF_SERVER_RESOURCES;
    }

    //
    // Round up the start of the work queue data structure to
    // the next cache line boundry
    //
    SrvWorkQueues = (PWORK_QUEUE)(((ULONG_PTR)SrvWorkQueuesBase + CACHE_LINE_SIZE-1) &
                    ~(CACHE_LINE_SIZE-1));
#endif


    eSrvWorkQueues = SrvWorkQueues + SrvNumberOfProcessors;

    RtlZeroMemory( SrvWorkQueues, (char *)eSrvWorkQueues - (char *)SrvWorkQueues );

    for( queue = SrvWorkQueues; queue < eSrvWorkQueues; queue++ ) {
        KeInitializeQueue( &queue->Queue, 1 );
        queue->WaitMode         = SrvProductTypeServer ? KernelMode : UserMode;
        queue->MaxThreads       = SrvMaxThreadsPerQueue;
        queue->MaximumWorkItems = SrvMaxReceiveWorkItemCount / SrvNumberOfProcessors;
        queue->MinFreeWorkItems = SrvMinReceiveQueueLength / SrvNumberOfProcessors;
        queue->MaxFreeRfcbs     = SrvMaxFreeRfcbs;
        queue->MaxFreeMfcbs     = SrvMaxFreeMfcbs;
        ExInitializeSListHead(&queue->InitialWorkItemList);
        ExInitializeSListHead(&queue->NormalWorkItemList);
        ExInitializeSListHead(&queue->RawModeWorkItemList);
        ExInitializeSListHead(&queue->RfcbFreeList);
        ExInitializeSListHead(&queue->MfcbFreeList);
        queue->PagedPoolLookAsideList.MaxSize  = SrvMaxPagedPoolChunkSize;
        queue->NonPagedPoolLookAsideList.MaxSize  = SrvMaxNonPagedPoolChunkSize;
        queue->CreateMoreWorkItems.CurrentWorkQueue = queue;
        queue->CreateMoreWorkItems.BlockHeader.ReferenceCount = 1;
        queue->IdleTimeOut.QuadPart = SrvIdleThreadTimeOut;

        INITIALIZE_SPIN_LOCK( &queue->SpinLock );
        SET_SERVER_TIME( queue );

#if MULTIPROCESSOR
        StartQueueDepthComputations( queue );
#endif
    }

    RtlZeroMemory( &SrvDoSWorkItem, sizeof(SPECIAL_WORK_ITEM) );
    SrvDoSWorkItem.BlockHeader.ReferenceCount = 1;
    SrvDoSWorkItemTearDown = SRV_DOS_TEARDOWN_MIN;
    KeInitializeSpinLock( &SrvDosSpinLock );

    //
    // Init the Blocking work queue
    //
    RtlZeroMemory( &SrvBlockingWorkQueue, sizeof( SrvBlockingWorkQueue ) );

    KeInitializeQueue( &SrvBlockingWorkQueue.Queue, 0 );

    SrvBlockingWorkQueue.WaitMode =
                SrvProductTypeServer ? KernelMode : UserMode;

    SrvBlockingWorkQueue.MaxThreads = SrvMaxThreadsPerQueue;
    SrvBlockingWorkQueue.IdleTimeOut.QuadPart = SrvIdleThreadTimeOut;

    //
    // If we are a multiprocessor server system, increase the number of blocking worker threads.
    //  Since most file opens end up being handled by the blocking queue, this can significantly
    //  improve performance for open-intensive workloads.
    //
    if( SrvProductTypeServer == TRUE && SrvNumberOfProcessors > 1 ) {
        SrvBlockingWorkQueue.MaxThreads *= 2;
    }

    SET_SERVER_TIME( &SrvBlockingWorkQueue );

    //
    // Build the receive work item list.
    //

    status = SrvAllocateInitialWorkItems( );
    if ( !NT_SUCCESS(status) ) {
        return status;
    }

    //
    // Build the raw mode work item list, and spread it around
    //  the processors
    //

    queue = SrvWorkQueues;
    for ( i = 0; i < SrvInitialRawModeWorkItemCount; i++ ) {

        SrvAllocateRawModeWorkItem( &workContext, queue );

        if ( workContext == NULL ) {
            return STATUS_INSUFFICIENT_RESOURCES;
        }

        GET_SERVER_TIME( queue, &workContext->Timestamp );

        SrvRequeueRawModeWorkItem( workContext );

        if( ++queue == eSrvWorkQueues )
            queue = SrvWorkQueues;
    }

    //
    // Create worker threads.
    //

    status = SrvCreateWorkerThreads( );
    if ( !NT_SUCCESS(status) ) {
        return status;
    }

    //
    // Initialize the scavenger.
    //

    status = SrvInitializeScavenger( );
    if ( !NT_SUCCESS(status) ) {
        return status;
    }

    //
    // Initialize the global ordered lists.
    //
    // *** WARNING:  Be careful when changing the locks associated with
    //     these ordered lists.  Certain places in the code depend on
    //     the level of the lock associated with a list.  Examples
    //     include (but are NOT limited to) SrvSmbSessionSetupAndX,
    //     SrvSmbTreeConnect, SrvSmbTreeConnectAndX, and CompleteOpen.
    //

    SrvInitializeOrderedList(
        &SrvEndpointList,
        FIELD_OFFSET( ENDPOINT, GlobalEndpointListEntry ),
        SrvCheckAndReferenceEndpoint,
        SrvDereferenceEndpoint,
        &SrvEndpointLock
        );

    SrvInitializeOrderedList(
        &SrvRfcbList,
        FIELD_OFFSET( RFCB, GlobalRfcbListEntry ),
        SrvCheckAndReferenceRfcb,
        SrvDereferenceRfcb,
        &SrvOrderedListLock
        );

    SrvInitializeOrderedList(
        &SrvSessionList,
        FIELD_OFFSET( SESSION, GlobalSessionListEntry ),
        SrvCheckAndReferenceSession,
        SrvDereferenceSession,
        &SrvOrderedListLock
        );

    SrvInitializeOrderedList(
        &SrvTreeConnectList,
        FIELD_OFFSET( TREE_CONNECT, GlobalTreeConnectListEntry ),
        SrvCheckAndReferenceTreeConnect,
        SrvDereferenceTreeConnect,
        &SrvShareLock
        );

    //
    // Open handle to NPFS.  Do not return an error if we fail so that
    // the server can still run without NPFS in the system.
    //

    SrvInitializeObjectAttributes_U(
        &objectAttributes,
        &SrvNamedPipeRootDirectory,
        0,
        NULL,
        NULL
        );

    status = IoCreateFile(
                &SrvNamedPipeHandle,
                GENERIC_READ | GENERIC_WRITE,
                &objectAttributes,
                &ioStatusBlock,
                NULL,
                FILE_ATTRIBUTE_NORMAL,
                FILE_SHARE_READ | FILE_SHARE_WRITE,
                FILE_OPEN,
                0,                      // Create Options
                NULL,                   // EA Buffer
                0,                      // EA Length
                CreateFileTypeNone,     // File type
                NULL,                   // ExtraCreateParameters
                IO_FORCE_ACCESS_CHECK   // Options
                );

    if (!NT_SUCCESS(status)) {

        INTERNAL_ERROR (
            ERROR_LEVEL_EXPECTED,
            "InitializeServer: Failed to open NPFS, err=%X\n",
            status,
            NULL
            );

        SrvLogServiceFailure( SRV_SVC_IO_CREATE_FILE_NPFS, status );
        SrvNamedPipeHandle = NULL;
        return status;

    } else {

        //
        // Get a pointer to the NPFS device object
        //

        status = SrvVerifyDeviceStackSize(
                                SrvNamedPipeHandle,
                                TRUE,
                                &SrvNamedPipeFileObject,
                                &SrvNamedPipeDeviceObject,
                                &handleInformation
                                );

        if ( !NT_SUCCESS( status )) {

            INTERNAL_ERROR(
                ERROR_LEVEL_EXPECTED,
                "InitializeServer: Verify Device Stack Size failed: %X\n",
                status,
                NULL
                );

            SrvNtClose( SrvNamedPipeHandle, FALSE );
            SrvNamedPipeHandle = NULL;
            return status;
        }
    }

    //
    // Initialize Dfs operations
    //
    SrvInitializeDfs();

    //
    // Intialize SrvAdminSecurityDescriptor, which allows Administrators READ access.
    //   This descriptor is used by the server to check if a user is an administrator
    //   in SrvIsAdmin().

    status = RtlCreateSecurityDescriptor( &SrvAdminSecurityDescriptor, SECURITY_DESCRIPTOR_REVISION );
    if( !NT_SUCCESS( status ) ) {
        return status;
    }

    //
    // Create an admin SID
    //
    AdminSid  = ALLOCATE_HEAP_COLD( RtlLengthRequiredSid( 2 ), BlockTypeAdminCheck );
    if( AdminSid == NULL ) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    RtlInitializeSid( AdminSid, &BuiltinAuthority, (UCHAR)2 );
    *(RtlSubAuthoritySid( AdminSid, 0 )) = SECURITY_BUILTIN_DOMAIN_RID;
    *(RtlSubAuthoritySid( AdminSid, 1 )) = DOMAIN_ALIAS_RID_ADMINS;

    length = sizeof(ACL) + sizeof( ACCESS_ALLOWED_ACE ) + RtlLengthSid( AdminSid );
    Acl = ALLOCATE_HEAP_COLD( length, BlockTypeAdminCheck );
    if( Acl == NULL ) {
        FREE_HEAP( AdminSid );
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    status = RtlCreateAcl( Acl, length, ACL_REVISION2 );

    if( NT_SUCCESS( status ) ) {
        status = RtlAddAccessAllowedAce( Acl, ACL_REVISION2, FILE_GENERIC_READ, AdminSid );
    }

    if( NT_SUCCESS( status ) ) {
        status = RtlSetDaclSecurityDescriptor( &SrvAdminSecurityDescriptor, TRUE, Acl, FALSE );
    }

    if( NT_SUCCESS( status ) ) {
        status = RtlSetOwnerSecurityDescriptor( &SrvAdminSecurityDescriptor, AdminSid, FALSE );
    }

    if( !NT_SUCCESS( status ) ) {
        return status;
    }

    //
    // Intialize SrvNullSessionSecurityDescriptor, which allows anonymous
    // logons READ access. This descriptor is used by the server to check
    // if a user is an null session in SrvIsNullSession().
    //

    status = RtlCreateSecurityDescriptor( &SrvNullSessionSecurityDescriptor, SECURITY_DESCRIPTOR_REVISION );
    if( !NT_SUCCESS( status ) ) {
        return status;
    }

    //
    // Create an anonymous SID
    //
    AnonymousSid  = ALLOCATE_HEAP_COLD( RtlLengthRequiredSid( 1 ), BlockTypeAdminCheck );
    if( AnonymousSid == NULL ) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    RtlInitializeSid( AnonymousSid, &BuiltinAuthority, (UCHAR)1 );
    *(RtlSubAuthoritySid( AnonymousSid, 0 )) = SECURITY_ANONYMOUS_LOGON_RID;

    length = sizeof(ACL) + sizeof( ACCESS_ALLOWED_ACE ) + RtlLengthSid( AnonymousSid );
    Acl = ALLOCATE_HEAP_COLD( length, BlockTypeAdminCheck );
    if( Acl == NULL ) {
        FREE_HEAP( AnonymousSid );
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    status = RtlCreateAcl( Acl, length, ACL_REVISION2 );

    if( NT_SUCCESS( status ) ) {
        status = RtlAddAccessAllowedAce( Acl, ACL_REVISION2, FILE_GENERIC_READ, AnonymousSid );
    }

    if( NT_SUCCESS( status ) ) {
        status = RtlSetDaclSecurityDescriptor( &SrvNullSessionSecurityDescriptor, TRUE, Acl, FALSE );
    }

    if( NT_SUCCESS( status ) ) {
        status = RtlSetOwnerSecurityDescriptor( &SrvNullSessionSecurityDescriptor, AnonymousSid, FALSE );
    }

    if( !NT_SUCCESS( status ) ) {
        return status;
    }

    (VOID) InitSecurityInterface();

    status = SrvValidateUser(
                &SrvNullSessionToken,
                NULL,
                NULL,
                NULL,
                StrNullAnsi,
                1,
                NULL,
                0,
                FALSE,
                NULL
                );

    if ( !NT_SUCCESS(status) ) {

        //
        // LSA doesn't want to let the null session in.  He's the boss!
        //
        INVALIDATE_SECURITY_HANDLE( SrvNullSessionToken );
    }

    //
    // See if the filesystems are allowing extended characters in 8.3 names.  If
    //  so, we need to filter them out ourself.
    //
    RtlInitUnicodeString( &string, StrRegExtendedCharsInPath );
    InitializeObjectAttributes( &objectAttributes,
                                &string,
                                OBJ_CASE_INSENSITIVE,
                                NULL,
                                NULL
                              );

    status = ZwOpenKey( &handle, KEY_READ, &objectAttributes );

    if( NT_SUCCESS( status ) ) {
        ULONG resultLength;
        union {
            KEY_VALUE_FULL_INFORMATION;
            UCHAR   buffer[ sizeof( KEY_VALUE_FULL_INFORMATION ) + 100 ];
        } keyValueInformation;

        RtlInitUnicodeString( &string, StrRegExtendedCharsInPathValue );
        status = ZwQueryValueKey( handle,
                                  &string,
                                  KeyValueFullInformation,
                                  &keyValueInformation,
                                  sizeof( keyValueInformation ),
                                  &resultLength
                                );

        if( NT_SUCCESS( status ) &&
            keyValueInformation.Type == REG_DWORD &&
            keyValueInformation.DataLength != 0 ) {

            SrvFilterExtendedCharsInPath =
                *(PULONG)(((PUCHAR)(&keyValueInformation)) + keyValueInformation.DataOffset) ?
                TRUE : FALSE;
        }

        ZwClose( handle );
    }

    //
    // Get a handle to use in PoRegisterSystemState() calls
    //
    SrvPoRegistrationState = PoRegisterSystemState( NULL, 0 );

    //
    // Indicate that the server is active.
    //

    ACQUIRE_LOCK( &SrvConfigurationLock );

    SrvFspTransitioning = FALSE;
    SrvFspActive = TRUE;

    RELEASE_LOCK( &SrvConfigurationLock );

    return STATUS_SUCCESS;

} // InitializeServer


STATIC
NTSTATUS
TerminateServer ( VOID )

/*++

Routine Description:

    This routine terminates the server.  The following steps are performed:

        - Walk through SrvEndpointList and close all open endpoints.

        - Walk through the work context blocks in the work queues
            getting rid of them as appropiate

        - Close all shares open in the server

        - Deallocate the search table

Arguments:

Return Value:

    None.

--*/

{
    PLIST_ENTRY listEntry;
    PSINGLE_LIST_ENTRY singleListEntry;
    PENDPOINT endpoint;
    ULONG numberOfThreads;
    PWORK_CONTEXT workContext;
    PSHARE share;
    ULONG i;
    SPECIAL_WORK_ITEM WorkItem;
    PSRV_TIMER timer;
    PSID adminsid;
    PSID anonymoussid;
    PACL acl;
    BOOLEAN defaulted;
    BOOLEAN daclpresent;
    NTSTATUS status;
    PWORK_QUEUE queue;
    PIRP irp;
    PLIST_ENTRY listEntryRoot;

    PAGED_CODE( );

    IF_DEBUG(FSP1) KdPrint(( "LAN Manager server FSP terminating.\n" ));

    //
    // Do not receive PNP notifications anymore
    //
    if( SrvTdiNotificationHandle != NULL ) {

        status = TdiDeregisterPnPHandlers( SrvTdiNotificationHandle );

        if( !NT_SUCCESS( status ) ) {
            KdPrint(( "TdiDeregisterPnPHandlers status %X\n", status ));
            SrvLogServiceFailure( SRV_SVC_PNP_TDI_NOTIFICATION, status );
            return status;
        }

        SrvTdiNotificationHandle = NULL;
    }

    //
    // Make sure we are not processing any other configuration IRPs.  We know
    //  that no new configuration IRPs can enter the queue because SrvFspTransitioning
    //  has been set.
    //
    // First drain the configuration queue
    //
    while( 1 ) {

        ACQUIRE_LOCK( &SrvConfigurationLock );

        irp = DequeueConfigurationIrp( );

        RELEASE_LOCK( &SrvConfigurationLock );

        if( irp == NULL ) {
            break;
        }

        irp->IoStatus.Status = STATUS_SERVER_NOT_STARTED;
        IoCompleteRequest( irp, 2 );
        InterlockedDecrement( (PLONG)&SrvConfigurationIrpsInProgress );
    }

    //
    // Now wait until any already dequeued configuration IRPs have been completed.  We
    //  check for >1 because we need to account for our own IRP
    //
    while( SrvConfigurationIrpsInProgress > 1 ) {

        LARGE_INTEGER interval;

        interval.QuadPart = -1*10*1000*10; // .01 second

        ASSERT( (LONG)SrvConfigurationIrpsInProgress > 0 );

        KeDelayExecutionThread( KernelMode, FALSE, &interval );
    }

    //
    // If there are outstanding API requests in the server FSD,
    // wait for them to complete.  The last one to complete will
    // set SrvApiCompletionEvent.
    //

    ACQUIRE_LOCK( &SrvConfigurationLock );

    if ( SrvApiRequestCount != 0 ) {

        //
        // We must release the lock before waiting so that the FSD
        // threads can get it to decrement SrvApiRequestCount.
        //

        RELEASE_LOCK( &SrvConfigurationLock );


        for (;;) {
            NTSTATUS WaitStatus;

            //
            // Wait until the last API has completed.  Since
            // SrvFspTransitioning was set to TRUE earlier, we know that the
            // API that makes SrvApiRequestCount go to zero will set the
            // event.
            //
            // This wait allows us to make the assumption later on that no
            // other thread is operating on server data structures.
            //

            WaitStatus = KeWaitForSingleObject(
                             &SrvApiCompletionEvent,
                             UserRequest,
                             UserMode,   // let kernel stack be paged
                             FALSE,
                             NULL
                         );

            if (WaitStatus != STATUS_USER_APC) {
                break;
            }
        }

    } else {

        RELEASE_LOCK( &SrvConfigurationLock );
    }


    //
    // Close all the endpoints opened by the server.  This also results
    // in the connections, sessions, tree connects, and files opened
    // by the server being closed.
    //

    ACQUIRE_LOCK( &SrvEndpointLock );

    if ( SrvEndpointCount != 0 ) {

        listEntry = SrvEndpointList.ListHead.Flink;

        while ( listEntry != &SrvEndpointList.ListHead ) {

            endpoint = CONTAINING_RECORD(
                            listEntry,
                            ENDPOINT,
                            GlobalEndpointListEntry
                            );

            if ( GET_BLOCK_STATE(endpoint) != BlockStateActive ) {
                listEntry = listEntry->Flink;
                continue;
            }

            //
            // We don't want to hold the endpoint lock while we close
            // the endpoint (this causes lock level problems), so we have
            // to play some games.
            //
            // Reference the endpoint to ensure that it doesn't go away.
            // (We'll need its Flink later.)  Close the endpoint.  This
            // releases the endpoint lock.  Reacquire the endpoint lock.
            // Capture the address of the next endpoint.  Dereference the
            // current endpoint.
            //

            SrvReferenceEndpoint( endpoint );
            SrvCloseEndpoint( endpoint );

            ACQUIRE_LOCK( &SrvEndpointLock );

            listEntry = listEntry->Flink;
            SrvDereferenceEndpoint( endpoint );

        }

        RELEASE_LOCK( &SrvEndpointLock );

        for (;;) {
            NTSTATUS WaitStatus;

            //
            // Wait until all the endpoints have actually closed.
            //

            WaitStatus = KeWaitForSingleObject(
                            &SrvEndpointEvent,
                            UserRequest,
                            UserMode,   // let kernel stack be paged
                            FALSE,
                            NULL
                            );

            if (WaitStatus != STATUS_USER_APC) {
                break;
            }
        }

    } else {

        RELEASE_LOCK( &SrvEndpointLock );

    }

    KeClearEvent( &SrvEndpointEvent );

    //
    // All the endpoints are closed, so it's impossible for there to
    // be any outstanding requests to xactsrv.  So shut it down.
    //
    SrvXsDisconnect();

    //
    // Queue a special work item to each of the work queues.  This
    // work item, when received by a worker thread. causes the thread
    // to requeue the work item and terminate itself.  In this way,
    // each of the worker threads receives the work item and kills
    // itself.
    //

    WorkItem.FspRestartRoutine = SrvTerminateWorkerThread;
    SET_BLOCK_TYPE( &WorkItem, BlockTypeWorkContextSpecial );

    //
    // Kill the threads on the nonblocking work queues
    //

    if ( SrvWorkQueues != NULL ) {

        for( queue=SrvWorkQueues; queue && queue < eSrvWorkQueues; queue++ ) {

            WorkItem.CurrentWorkQueue = queue;

            SrvInsertWorkQueueTail(
                queue,
                (PQUEUEABLE_BLOCK_HEADER)&WorkItem
                );

            //
            // Wait for the threads to all die
            //
            while( queue->Threads != 0 ) {

                LARGE_INTEGER interval;

                interval.QuadPart = -1*10*1000*10; // .01 second

                KeDelayExecutionThread( KernelMode, FALSE, &interval );
            }

            KeRundownQueue( &queue->Queue );
        }

        //
        // Kill the threads on the blocking work queues
        //
        WorkItem.CurrentWorkQueue = &SrvBlockingWorkQueue;

        SrvInsertWorkQueueTail(
            &SrvBlockingWorkQueue,
            (PQUEUEABLE_BLOCK_HEADER)&WorkItem
            );

        //
        // Wait for the threads to all die
        //
        while( SrvBlockingWorkQueue.Threads != 0 ) {

            LARGE_INTEGER interval;

            interval.QuadPart = -1*10*1000*10; // .01 second

            KeDelayExecutionThread( KernelMode, FALSE, &interval );
        }

        KeRundownQueue( &SrvBlockingWorkQueue.Queue );
    }

    //
    // Free any space allocated for the Null Session pipe and share lists
    //
    SrvFreeRegTables();

    //
    // If we allocated memory for the os version strings, free it now.
    //

    if ( SrvNativeOS.Buffer != NULL &&
         SrvNativeOS.Buffer != StrDefaultNativeOs ) {

        FREE_HEAP( SrvNativeOS.Buffer );
        SrvNativeOS.Buffer = NULL;

        RtlFreeOemString( &SrvOemNativeOS );
        SrvOemNativeOS.Buffer = NULL;
    }

    //
    // If allocated memory for the display name, free it now.
    //

    if ( SrvAlertServiceName != NULL &&
         SrvAlertServiceName != StrDefaultSrvDisplayName ) {

        FREE_HEAP( SrvAlertServiceName );
        SrvAlertServiceName = NULL;
    }

    //
    // Make sure the scavenger is not running.
    //

    SrvTerminateScavenger( );

#if MULTIPROCESSOR
    if( SrvWorkQueues ) {
        for( queue = SrvWorkQueues; queue < eSrvWorkQueues; queue++ ) {
            StopQueueDepthComputations( queue );
        }
    }
#endif


    //
    // Free the work items in the work queues and the receive work item
    // list.  This also deallocates the SMB buffers.  Note that work
    // items allocated dynamically may be deallocated singly, while work
    // items allocated at server startup are part of one large block,
    // and may not be deallocated singly.
    //
    // !!! Does this properly clean up buffers allocated during SMB
    //     processing?  Probably not.  Should probably allow the worker
    //     threads to run the work queue normally before they stop.
    //

    if( SrvWorkQueues ) {

        for( queue = SrvWorkQueues; queue < eSrvWorkQueues; queue++ ) {

            //
            // Clean out the single FreeContext spot
            //
            workContext = NULL;
            workContext = (PWORK_CONTEXT)InterlockedExchangePointer(
                                            &queue->FreeContext, workContext );

            if( workContext != NULL && workContext->PartOfInitialAllocation == FALSE ) {
                SrvFreeNormalWorkItem( workContext );
            }

            //
            // Clean out the normal work item list
            //
            while( 1 ) {
                singleListEntry = ExInterlockedPopEntrySList(
                                            &queue->NormalWorkItemList, &queue->SpinLock );
                if( singleListEntry == NULL ) {
                    break;
                }
                workContext =
                    CONTAINING_RECORD( singleListEntry, WORK_CONTEXT, SingleListEntry );

                SrvFreeNormalWorkItem( workContext );
                queue->FreeWorkItems--;
            }

            //
            // Clean out the raw mode work item list
            //
            while( 1 ) {
                singleListEntry = ExInterlockedPopEntrySList(
                                            &queue->RawModeWorkItemList, &queue->SpinLock );
                if( singleListEntry == NULL ) {
                    break;
                }

                workContext =
                    CONTAINING_RECORD( singleListEntry, WORK_CONTEXT, SingleListEntry );

                SrvFreeRawModeWorkItem( workContext );
            }

            //
            // Free up any saved rfcbs
            //
            if( queue->CachedFreeRfcb != NULL ) {
                FREE_HEAP( queue->CachedFreeRfcb->PagedRfcb );
                DEALLOCATE_NONPAGED_POOL( queue->CachedFreeRfcb );
                queue->CachedFreeRfcb = NULL;
            }

            while( 1 ) {
                PRFCB Rfcb;

                singleListEntry = ExInterlockedPopEntrySList( &queue->RfcbFreeList, &queue->SpinLock );
                if( singleListEntry == NULL ) {
                    break;
                }

                Rfcb =
                    CONTAINING_RECORD( singleListEntry, RFCB, SingleListEntry );
                FREE_HEAP( Rfcb->PagedRfcb );
                DEALLOCATE_NONPAGED_POOL( Rfcb );
            }

            //
            // Free up any saved mfcbs
            //
            if( queue->CachedFreeMfcb != NULL ) {
                DEALLOCATE_NONPAGED_POOL( queue->CachedFreeMfcb );
                queue->CachedFreeMfcb = NULL;
            }

            while( 1 ) {
                PNONPAGED_MFCB nonpagedMfcb;

                singleListEntry = ExInterlockedPopEntrySList( &queue->MfcbFreeList, &queue->SpinLock );
                if( singleListEntry == NULL ) {
                    break;
                }

                nonpagedMfcb =
                    CONTAINING_RECORD( singleListEntry, NONPAGED_MFCB, SingleListEntry );

                DEALLOCATE_NONPAGED_POOL( nonpagedMfcb );
            }
        }

    } // SrvWorkQueues

    //
    // All dynamic work items have been freed, and the work item queues
    // have been emptied.  Release the initial work item allocation.
    //
    SrvFreeInitialWorkItems( );

    //
    // Walk through the global share list, closing them all.
    //

    for( listEntryRoot = SrvShareHashTable;
         listEntryRoot < &SrvShareHashTable[ NSHARE_HASH_TABLE ];
         listEntryRoot++ ) {

        while( listEntryRoot->Flink != listEntryRoot ) {

            share = CONTAINING_RECORD( listEntryRoot->Flink, SHARE, GlobalShareList );

            SrvCloseShare( share );
        }
    }

    //
    // If we opened the NPFS during initialization, close the handle now
    // and dereference the NPFS file object.
    //

    if ( SrvNamedPipeHandle != NULL) {

        SrvNtClose( SrvNamedPipeHandle, FALSE );
        ObDereferenceObject( SrvNamedPipeFileObject );

        SrvNamedPipeHandle = NULL;

    }

    //
    // Disconnect from the Dfs driver
    //
    SrvTerminateDfs();

    //
    // Clean up the Dns Domain Name if necessary
    //
    if( SrvDnsDomainName )
    {
        DEALLOCATE_NONPAGED_POOL( SrvDnsDomainName );
        SrvDnsDomainName = NULL;
    }

    //
    // Clean up the admin security descriptor
    //


    status = RtlGetDaclSecurityDescriptor( &SrvAdminSecurityDescriptor,
                                           &daclpresent,
                                           &acl,
                                           &defaulted );
    if( !NT_SUCCESS( status ) || !daclpresent ) {
        acl = NULL;
    }

    status = RtlGetOwnerSecurityDescriptor( &SrvAdminSecurityDescriptor,
                                            &adminsid,
                                            &defaulted );

    if( NT_SUCCESS( status ) && adminsid != NULL ) {
        FREE_HEAP( adminsid );
    }

    if( acl != NULL ) {
        FREE_HEAP( acl );
    }

    //
    // Clean up the null session security descriptor
    //

    status = RtlGetDaclSecurityDescriptor( &SrvNullSessionSecurityDescriptor,
                                           &daclpresent,
                                           &acl,
                                           &defaulted );
    if( !NT_SUCCESS( status ) || !daclpresent ) {
        acl = NULL;
    }

    status = RtlGetOwnerSecurityDescriptor( &SrvNullSessionSecurityDescriptor,
                                            &anonymoussid,
                                            &defaulted );

    if( NT_SUCCESS( status ) && anonymoussid != NULL ) {
        FREE_HEAP( anonymoussid );
    }

    if( acl != NULL ) {
        FREE_HEAP( acl );
    }


    if (!CONTEXT_NULL(SrvNullSessionToken)) {
        DeleteSecurityContext(&SrvNullSessionToken);
        INVALIDATE_SECURITY_HANDLE( SrvNullSessionToken );
    }

    //
    // Delete the global ordered lists.
    //

    SrvDeleteOrderedList( &SrvEndpointList );
    SrvDeleteOrderedList( &SrvRfcbList );
    SrvDeleteOrderedList( &SrvSessionList );
    SrvDeleteOrderedList( &SrvTreeConnectList );

    //
    // Clear out the timer pool.
    //

    while ( (singleListEntry = ExInterlockedPopEntrySList(
                                    &SrvTimerList,
                                    &GLOBAL_SPIN_LOCK(Timer) )) != NULL ) {
        timer = CONTAINING_RECORD( singleListEntry, SRV_TIMER, Next );
        DEALLOCATE_NONPAGED_POOL( timer );
    }

    if( SrvWorkQueues ) {

        //
        // Clear out the saved pool chunks
        //
        for( queue = SrvWorkQueues; queue < eSrvWorkQueues; queue++ ) {
            //
            // Free up any paged pool that we've saved.
            //
            SrvClearLookAsideList( &queue->PagedPoolLookAsideList, SrvFreePagedPool );

            //
            // Free up any nonpaged pool that we've saved.
            //
            SrvClearLookAsideList( &queue->NonPagedPoolLookAsideList, SrvFreeNonPagedPool );
        }

#if MULTIPROCESSOR
        DEALLOCATE_NONPAGED_POOL( SrvWorkQueuesBase );
        SrvWorkQueuesBase = NULL;
        SrvWorkQueues = NULL;
#endif
    }

    //
    // Unlock pageable sections.
    //

    for ( i = 0; i < SRV_CODE_SECTION_MAX; i++ ) {
        if ( SrvSectionInfo[i].Handle != NULL ) {
            ASSERT( SrvSectionInfo[i].ReferenceCount != 0 );
            MmUnlockPagableImageSection( SrvSectionInfo[i].Handle );
            SrvSectionInfo[i].Handle = 0;
            SrvSectionInfo[i].ReferenceCount = 0;
        }
    }

    //
    // Zero out the statistics database.
    //

    RtlZeroMemory( &SrvStatistics, sizeof(SrvStatistics) );
#if SRVDBG_STATS || SRVDBG_STATS2
    RtlZeroMemory( &SrvDbgStatistics, sizeof(SrvDbgStatistics) );
#endif

    //
    // Free the handle used in PoRegisterSystemState
    //
    if( SrvPoRegistrationState != NULL ) {
        PoUnregisterSystemState( SrvPoRegistrationState );
        SrvPoRegistrationState = NULL;
    }

    //
    // Indicate that the server is no longer active.
    //

    ACQUIRE_LOCK( &SrvConfigurationLock );

    SrvFspTransitioning = FALSE;
    SrvFspActive = FALSE;
    SrvSvcProcess = NULL;

    RELEASE_LOCK( &SrvConfigurationLock );

    IF_DEBUG(FSP1) KdPrint(( "LAN Manager server FSP termination complete.\n" ));

    return STATUS_SUCCESS;

} // TerminateServer

VOID
SrvFreeRegTables (
    VOID
    )
/*++

Routine Description:

    This routine frees space allocated for the list of legal Null session shares
     and pipes.  The SrvConfigurationLock must be held when this routine is called.

Arguments:

    None.

Return Value:

    None.

--*/
{
    PAGED_CODE( );

    //
    // If we allocated a buffer for the list of null session pipes,
    // free it now.
    //

    if ( SrvNullSessionPipes != NULL &&
         SrvNullSessionPipes != StrDefaultNullSessionPipes ) {

        FREE_HEAP( SrvNullSessionPipes );
    }
    SrvNullSessionPipes = NULL;

    if( SrvNoRemapPipeNames != NULL &&
        SrvNoRemapPipeNames != StrDefaultNoRemapPipeNames ) {

        FREE_HEAP( SrvNoRemapPipeNames );
    }
    SrvNoRemapPipeNames = NULL;


    if ( SrvPipesNeedLicense != NULL &&
         SrvPipesNeedLicense != StrDefaultPipesNeedLicense ) {

        FREE_HEAP( SrvPipesNeedLicense );
    }
    SrvPipesNeedLicense = NULL;

    if ( SrvNullSessionShares != NULL &&
         SrvNullSessionShares != StrDefaultNullSessionShares ) {

        FREE_HEAP( SrvNullSessionShares );
    }
    SrvNullSessionShares = NULL;

#if SRVNTVERCHK
    if( SrvInvalidDomainNames != NULL ) {
        FREE_HEAP( SrvInvalidDomainNames );
    }
    SrvInvalidDomainNames = NULL;
#endif

#if SRVCATCH
    if( SrvCatchBuf != NULL ) {
        FREE_HEAP( SrvCatchBuf );
        SrvCatchBuf = NULL;
    }
    if( SrvCatchExtBuf != NULL ) {
        FREE_HEAP( SrvCatchExtBuf );
        SrvCatchExtBuf = NULL;
    }
    if( SrvCatchShareNames != NULL ) {
        FREE_HEAP( SrvCatchShareNames );
        SrvCatchShareNames = NULL;
        SrvCatchShares = 0;
        CleanupCrcTable();
    }
#endif
}

VOID
SrvGetRegTables (
    VOID
    )
/*++

Routine Description:

    This routine loads the lists of valid shares and pipes for null sessions.
      The SrvConfigurationLock must be held when this routine is called.

Arguments:

    None.

Return Value:

    None.

--*/
{
    PWSTR *strErrorLogIgnore;

    PAGED_CODE( );

    //
    // Get the list of null session pipes.
    //
    ASSERT( SrvNullSessionPipes == NULL );
    SrvGetMultiSZList(
            &SrvNullSessionPipes,
            StrRegSrvParameterPath,
            StrRegNullSessionPipes,
            StrDefaultNullSessionPipes
            );

    //
    // Get the list of non-remappable pipe names
    //
    ASSERT( SrvNoRemapPipeNames == NULL );
    SrvGetMultiSZList(
            &SrvNoRemapPipeNames,
            StrRegSrvParameterPath,
            StrRegNoRemapPipes,
            StrDefaultNoRemapPipeNames
            );

    //
    // Get the list of pipes requiring licenses
    //
    ASSERT( SrvPipesNeedLicense == NULL );
    SrvGetMultiSZList(
            &SrvPipesNeedLicense,
            StrRegSrvParameterPath,
            StrRegPipesNeedLicense,
            StrDefaultPipesNeedLicense
            );

    //
    // Get the list of null session pipes.
    //
    ASSERT( SrvNullSessionShares == NULL );
    SrvGetMultiSZList(
            &SrvNullSessionShares,
            StrRegSrvParameterPath,
            StrRegNullSessionShares,
            StrDefaultNullSessionShares
            );

#if SRVCATCH
    {
    USHORT i;

    SrvCatch.Length = 0;
    SrvCatch.Buffer = 0;
    if( SrvCatchBuf != NULL ) {
        FREE_HEAP( SrvCatchBuf );
        SrvCatchBuf = NULL;
    }

    SrvGetMultiSZList(
                &SrvCatchBuf,
                StrRegSrvParameterPath,
                L"CheckFile",
                0
                );

    if( SrvCatchBuf != NULL ) {
        SrvCatch.Buffer = SrvCatchBuf[0];
        for( i = 0; SrvCatch.Buffer[i]; i++ )
            ;
        SrvCatch.Length = i * sizeof( SrvCatch.Buffer[0] );
    }

    SrvCatchExt.Length = 0;
    SrvCatchExt.Buffer = 0;
    if( SrvCatchExtBuf != NULL )
    {
        FREE_HEAP( SrvCatchExtBuf );
        SrvCatchExtBuf = NULL;
    }
    SrvGetMultiSZList(
                &SrvCatchExtBuf,
                StrRegSrvParameterPath,
                L"CheckExtension",
                0
                );

    if( SrvCatchExtBuf != NULL ) {
        SrvCatchExt.Buffer = SrvCatchExtBuf[0];
        for( i = 0; SrvCatchExt.Buffer[i]; i++ )
            ;
        SrvCatchExt.Length = i * sizeof( SrvCatchExt.Buffer[0] );
    }
    if( SrvCatchShareNames != NULL )
    {
        FREE_HEAP( SrvCatchShareNames );
        SrvCatchShareNames = NULL;
    }
    SrvGetMultiSZList(
        &SrvCatchShareNames,
        StrRegSrvParameterPath,
        L"CheckShares",
        0
        );
    if( SrvCatchShareNames != NULL )
    {
        for( i=0; SrvCatchShareNames[i]; i++ ) ;
        SrvCatchShares = i;
    }

    if( SrvCatchShares > 0 )
    {
        if( !GenerateCrcTable() )
        {
            FREE_HEAP( SrvCatchShareNames );
            SrvCatchShareNames = NULL;
            SrvCatchShares = 0;
        }
    }
    }
#endif

    //
    // Get the list of error codes that we don't log
    //

    SrvGetMultiSZList(
            &strErrorLogIgnore,
            StrRegSrvParameterPath,
            StrRegErrorLogIgnore,
            StrDefaultErrorLogIgnore
            );

    if( strErrorLogIgnore != NULL ) {
        DWORD i;

        //
        // They came in as strings, convert to NTSTATUS codes
        //
        for( i=0; i < SRVMAXERRLOGIGNORE; i++ ) {
            NTSTATUS Status;
            PWSTR p;

            if( (p = strErrorLogIgnore[i]) == NULL )
                break;

            for( Status = 0; *p; p++ ) {
                if( *p >= L'A' && *p <= L'F' ) {
                    Status <<= 4;
                    Status += 10 + (*p - L'A');
                } else if( *p >= '0' && *p <= '9' ) {
                    Status <<= 4;
                    Status += *p - L'0';
                }
            }

            SrvErrorLogIgnore[i] = Status;

            IF_DEBUG(FSP1) KdPrint(( "LAN Manager server:  %X errs not logged\n", Status ));
        }
        SrvErrorLogIgnore[i] = 0;

        if( strErrorLogIgnore != StrDefaultErrorLogIgnore ) {
            FREE_HEAP( strErrorLogIgnore );
        }
    }

#if SRVNTVERCHK
    //
    // Get the list of Domains that we disallow if the client
    //  is running NT5
    //
    ASSERT( SrvInvalidDomainNames == NULL );
    SrvGetMultiSZList(
            &SrvInvalidDomainNames,
            StrRegSrvParameterPath,
            StrRegInvalidDomainNames,
            NULL
            );

    if( SrvInvalidDomainNames != NULL ) {

        int i;

        KdPrint(( "SRV disallows NT5 clients from the following domains:\n" ));
        for( i = 0; SrvInvalidDomainNames[i]; i++ ) {
            KdPrint(( " %ws\n", SrvInvalidDomainNames[i] ));
        }
    }

    //
    // Get the list of IP addresses of clients that we will allow to connect
    //  regardless of build number
    //
    {
    PWSTR *strAllowedIPAddresses;
    int i;

    //
    // Wipe out the current list
    //
    RtlZeroMemory( SrvAllowIPAddress, sizeof( SrvAllowIPAddress ) );

    SrvGetMultiSZList(
        &strAllowedIPAddresses,
        StrRegSrvParameterPath,
        StrRegAllowedIPAddresses,
        NULL
        );

    if( strAllowedIPAddresses != NULL ) {

        KdPrint(( "SRV ignores NT build version of clients at following IP addrs:\n" ));
        //
        // Fill it with the new ones
        //
        for(i = 0;
            strAllowedIPAddresses[i] &&
             i < (sizeof(SrvAllowIPAddress)/sizeof(SrvAllowIPAddress[0]))-1;
            i++ ) {

            LPWSTR p;
            DWORD addr = 0;
            char *s = (char *)&addr;

            //
            // Convert the IP address to a DWORD and store it
            //
            for( p = strAllowedIPAddresses[i]; *p && s < ((char *)&addr)+sizeof(addr); p++ ) {
                if( *p == L'.' ) {
                    s++;
                } else if( *p >= '0' && *p <= '9' ) {
                    *s = (*s * 10) + (*p - L'0');
                }
            }

            SrvAllowIPAddress[i] = addr;

            KdPrint(( "    %ws\n", strAllowedIPAddresses[i] ));

        }
        FREE_HEAP( strAllowedIPAddresses );
    }

    }
#endif
}

#if SRVNTVERCHK
VOID
SrvGetRegClientNumber (
    VOID
    )
/*++

Routine Description:

    This routine reads MinNt5Client REG_DWORD from the registry and sets
    the global SrvMinNT5Client to the retrieved value.  Later, if a client
    running >= NT5 with a build number less than SrvMinNT5Client tries to
    connect to a disk share, we reject the connection.  This mechanism
    is used on our SLM servers to ensure that people are upgrading to
    current builds.

--*/
{
    UNICODE_STRING unicodeKeyName;
    UNICODE_STRING unicodeParamPath;
    OBJECT_ATTRIBUTES objAttributes;
    HANDLE keyHandle;
    PKEY_VALUE_PARTIAL_INFORMATION infoBuffer;
    ULONG lengthNeeded;
    NTSTATUS status;

    PAGED_CODE( );

    SrvMinNT5Client = 0;
    SrvMinNT5ClientIPCToo = FALSE;

    RtlInitUnicodeString( &unicodeParamPath, StrRegSrvParameterPath );
    RtlInitUnicodeString( &unicodeKeyName, L"MinNT5Client" );

    InitializeObjectAttributes(
                        &objAttributes,
                        &unicodeParamPath,
                        OBJ_CASE_INSENSITIVE,
                        NULL,
                        NULL
                        );

    status = ZwOpenKey(
                    &keyHandle,
                    KEY_QUERY_VALUE,
                    &objAttributes
                    );


    if ( NT_SUCCESS(status) ) {

        status = ZwQueryValueKey(
                        keyHandle,
                        &unicodeKeyName,
                        KeyValuePartialInformation,
                        NULL,
                        0,
                        &lengthNeeded
                        );

        if( status != STATUS_BUFFER_TOO_SMALL ) {

            RtlInitUnicodeString( &unicodeKeyName, L"MinNT5ClientIPC" );

            status = ZwQueryValueKey(
                            keyHandle,
                            &unicodeKeyName,
                            KeyValuePartialInformation,
                            NULL,
                            0,
                            &lengthNeeded
                            );

            SrvMinNT5ClientIPCToo = TRUE;
        }

        if( status == STATUS_BUFFER_TOO_SMALL ) {

            infoBuffer = ALLOCATE_HEAP_COLD( lengthNeeded, BlockTypeDataBuffer );

            if( infoBuffer ) {

                status = ZwQueryValueKey(
                            keyHandle,
                            &unicodeKeyName,
                            KeyValuePartialInformation,
                            infoBuffer,
                            lengthNeeded,
                            &lengthNeeded
                            );

                if( NT_SUCCESS( status ) &&
                    infoBuffer->Type == REG_DWORD &&
                    infoBuffer->DataLength == sizeof( DWORD )  ) {

                    SrvMinNT5Client = *(DWORD *)(&infoBuffer->Data[0]);

                    KdPrint(( "SRV: Restrict NT5 clients to builds >= %u\n",
                        SrvMinNT5Client ));

                    if( SrvMinNT5ClientIPCToo ) {
                        KdPrint(( "    Restrict IPC clients\n" ));
                    }
                }

                FREE_HEAP( infoBuffer );
            }
        }

        NtClose( keyHandle );
    }
}
#endif

#if MULTIPROCESSOR
VOID
StartQueueDepthComputations(
    PWORK_QUEUE queue
    )
{
    LARGE_INTEGER currentTime;

    PAGED_CODE();

    if( SrvNumberOfProcessors == 1 )
        return;

    //
    // We're going to schedule a dpc to call the 'ComputeAvgQueueDepth' routine
    //   Initialize the dpc
    //
    KeInitializeDpc( &queue->QueueAvgDpc, ComputeAvgQueueDepth, queue );

    //
    // We want to make sure the dpc runs on the same processor handling the
    //   queue -- to avoid thrashing the cache
    //
    KeSetTargetProcessorDpc( &queue->QueueAvgDpc, (CCHAR)(queue - SrvWorkQueues));

    //
    // Initialize a timer object to schedule our dpc later
    //
    KeInitializeTimer( &queue->QueueAvgTimer );
    KeQuerySystemTime( &currentTime );
    queue->NextAvgUpdateTime.QuadPart = currentTime.QuadPart + SrvQueueCalc.QuadPart;

    //
    // Initialize the sample vector
    //
    queue->NextSample = queue->DepthSamples;
    RtlZeroMemory( queue->DepthSamples, sizeof( queue->DepthSamples ) );

    //
    // And start it going!
    //
    KeSetTimer( &queue->QueueAvgTimer, queue->NextAvgUpdateTime, &queue->QueueAvgDpc );
}

VOID
StopQueueDepthComputations(
    PWORK_QUEUE queue
    )
{
    KIRQL oldIrql;

    if( SrvNumberOfProcessors == 1 )
        return;

    KeInitializeEvent( &queue->AvgQueueDepthTerminationEvent,
                       NotificationEvent,
                       FALSE
                     );


    ACQUIRE_SPIN_LOCK( &queue->SpinLock, &oldIrql );

    queue->NextSample = NULL;

    RELEASE_SPIN_LOCK( &queue->SpinLock, oldIrql );

    //
    // Cancel the computation timer.  If this works, then we know that
    //  the DPC code is not running.  Otherwise, it is running or queued
    //  to run and we need to wait until it completes.
    //
    if( !KeCancelTimer( &queue->QueueAvgTimer ) ) {
        KeWaitForSingleObject(
            &queue->AvgQueueDepthTerminationEvent,
            Executive,
            KernelMode,
            FALSE,
            NULL
            );
    }
}

VOID
ComputeAvgQueueDepth (
    IN PKDPC Dpc,
    IN PVOID DeferredContext,
    IN PVOID SystemArgument1,
    IN PVOID SystemArgument2
    )
{
    LARGE_INTEGER currentTime;
    PWORK_QUEUE queue = (PWORK_QUEUE)DeferredContext;

    ACQUIRE_DPC_SPIN_LOCK( &queue->SpinLock );

    if( queue->NextSample == NULL ) {

        KeSetEvent( &queue->AvgQueueDepthTerminationEvent, 0, FALSE );

    } else {

        //
        // Compute the sliding window average by taking a queue depth
        // sample, removing the old sample value from the running sum
        // and adding in the new value
        //

        currentTime.LowPart= PtrToUlong(SystemArgument1);
        currentTime.HighPart = PtrToUlong(SystemArgument2);

        queue->AvgQueueDepthSum -= *queue->NextSample;
        *(queue->NextSample) = KeReadStateQueue( &queue->Queue );
        queue->AvgQueueDepthSum += *queue->NextSample;

        if( ++(queue->NextSample) == &queue->DepthSamples[ QUEUE_SAMPLES ] )
            queue->NextSample = queue->DepthSamples;

        queue->NextAvgUpdateTime.QuadPart =
               currentTime.QuadPart + SrvQueueCalc.QuadPart;

        KeSetTimer( &queue->QueueAvgTimer,
                    queue->NextAvgUpdateTime,
                    &queue->QueueAvgDpc );
    }

    RELEASE_DPC_SPIN_LOCK( &queue->SpinLock );
}
#endif  // MULTIPROCESSOR