889 lines
25 KiB
C
889 lines
25 KiB
C
/*++
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Copyright (c) 1989 Microsoft Corporation
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Module Name:
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misc.c
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Abstract:
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This module contains the code to implement the NtFlushBuffersFile,
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NtSetNewSizeFile, and NtCancelIoFile system services for the NT
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I/O system.
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Author:
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Darryl E. Havens (darrylh) 22-Jun-1989
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Environment:
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Kernel mode only
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Revision History:
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--*/
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#include "iop.h"
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#ifdef ALLOC_PRAGMA
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#pragma alloc_text(PAGE, NtCancelIoFile)
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#pragma alloc_text(PAGE, NtDeleteFile)
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#pragma alloc_text(PAGE, NtFlushBuffersFile)
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#pragma alloc_text(PAGE, NtQueryAttributesFile)
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#pragma alloc_text(PAGE, NtQueryFullAttributesFile)
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#endif
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NTSTATUS
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NtCancelIoFile(
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IN HANDLE FileHandle,
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OUT PIO_STATUS_BLOCK IoStatusBlock
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)
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/*++
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Routine Description:
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This service causes all pending I/O operations for the specified file to be
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marked as canceled. Most types of operations can be canceled immediately,
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while others may continue toward completion before they are actually
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canceled and the caller is notified.
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Only those pending operations that were issued by the current thread using
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the specified handle are canceled. Any operations issued for the file by
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any other thread or any other process continues normally.
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Arguments:
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FileHandle - Supplies a handle to the file whose operations are to be
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canceled.
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IoStatusBlock - Address of the caller's I/O status block.
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Return Value:
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The status returned is the final completion status of the operation.
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--*/
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{
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PIRP irp;
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NTSTATUS status;
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PFILE_OBJECT fileObject;
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KPROCESSOR_MODE requestorMode;
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PETHREAD thread;
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BOOLEAN found = FALSE;
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PLIST_ENTRY header;
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PLIST_ENTRY entry;
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KIRQL irql;
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PAGED_CODE();
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//
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// Get the previous mode; i.e., the mode of the caller.
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//
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requestorMode = KeGetPreviousMode();
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if (requestorMode != KernelMode) {
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//
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// The caller's access mode is user, so probe each of the arguments
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// and capture them as necessary. If any failures occur, the condition
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// handler will be invoked to handle them. It will simply cleanup and
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// return an access violation status code back to the system service
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// dispatcher.
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//
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try {
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//
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// The IoStatusBlock parameter must be writeable by the caller.
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//
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ProbeForWriteIoStatus( IoStatusBlock );
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} except(EXCEPTION_EXECUTE_HANDLER) {
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//
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// An exception was incurred attempting to probe the caller'
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// I/O status block. Simply return an appropriate error status
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// code.
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//
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return GetExceptionCode();
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}
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}
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//
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// There were no blatant errors so far, so reference the file object so
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// the target device object can be found. Note that if the handle does
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// not refer to a file object, or if the caller does not have the required
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// access to the file, then it will fail.
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//
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status = ObReferenceObjectByHandle( FileHandle,
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0,
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IoFileObjectType,
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requestorMode,
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(PVOID *) &fileObject,
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NULL );
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if (!NT_SUCCESS( status )) {
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return(status);
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}
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//
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// Note that here the I/O system would normally make a check to determine
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// whether or not the file was opened for synchronous I/O. If it was, then
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// it would attempt to exclusively acquire the file object lock. However,
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// since this service is attempting to cancel all of the I/O for the file,
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// it does not make much sense to wait until it has all completed before
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// attempting to cancel it.
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//
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//
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// Set the file object to the Not-Signaled state.
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//
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KeClearEvent( &fileObject->Event );
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//
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// Get the address of the current thread. The thread contains a list of
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// the pending operations for this file.
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//
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thread = PsGetCurrentThread();
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//
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// Update the operation count statistic for the current process for
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// operations other than read and write.
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//
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IopUpdateOtherOperationCount();
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//
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// Walk the list of IRPs on the thread's pending I/O queue looking for IRPs
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// which specify the same file as the FileHandle refers to. For each IRP
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// found, set its cancel flag. If no IRPs are found, simply complete the
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// I/O here. The only synchronization needed here is to block out all APCs
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// for this thread so that no I/O can complete and remove packets from the
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// queue. No considerations need be made for multi-processing since this
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// thread can only be running on one processor at a time and this routine
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// has control of the thread for now.
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//
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KeRaiseIrql( APC_LEVEL, &irql );
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header = &thread->IrpList;
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entry = thread->IrpList.Flink;
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while (header != entry) {
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//
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// An IRP has been found for this thread. If the IRP refers to the
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// appropriate file object, set its cancel flag and remember that it
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// was found; otherwise, simply continue the loop.
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//
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irp = CONTAINING_RECORD( entry, IRP, ThreadListEntry );
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if (irp->Tail.Overlay.OriginalFileObject == fileObject) {
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found = TRUE;
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IoCancelIrp( irp );
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}
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entry = entry->Flink;
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}
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//
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// Lower the IRQL back down to what it was on entry to this procedure.
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//
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KeLowerIrql( irql );
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if (found) {
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LARGE_INTEGER interval;
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//
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// Delay execution for a time and let the request
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// finish. The delay time is 10ms.
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//
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interval.QuadPart = -10 * 1000 * 10;
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//
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// Wait for a while so the canceled requests can complete.
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//
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while (found) {
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(VOID) KeDelayExecutionThread( KernelMode, FALSE, &interval );
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found = FALSE;
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//
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// Raise the IRQL to prevent modification to the IRP list by the
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// thread's APC routine.
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//
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KeRaiseIrql( APC_LEVEL, &irql );
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//
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// Check the IRP list for requests which refer to the specified
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// file object.
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//
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entry = thread->IrpList.Flink;
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while (header != entry) {
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//
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// An IRP has been found for this thread. If the IRP refers
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// to the appropriate file object, remember that it
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// was found; otherwise, simply continue the loop.
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//
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irp = CONTAINING_RECORD( entry, IRP, ThreadListEntry );
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if (irp->Tail.Overlay.OriginalFileObject == fileObject) {
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found = TRUE;
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break;
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}
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entry = entry->Flink;
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}
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//
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// Lower the IRQL back down to what it was on entry to this procedure.
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//
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KeLowerIrql( irql );
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}
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}
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try {
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//
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// Write the status back to the user.
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//
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IoStatusBlock->Status = STATUS_SUCCESS;
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IoStatusBlock->Information = 0L;
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} except(EXCEPTION_EXECUTE_HANDLER) {
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//
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// An exception was incurred attempting to write the caller's
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// I/O status block; however, the service completed sucessfully so
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// just return sucess.
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//
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}
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//
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// Set the file object event to the Signaled state.
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//
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(VOID) KeSetEvent( &fileObject->Event, 0, FALSE );
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//
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// Dereference the file object.
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//
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ObDereferenceObject( fileObject );
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return STATUS_SUCCESS;
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}
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NTSTATUS
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NtDeleteFile(
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IN POBJECT_ATTRIBUTES ObjectAttributes
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)
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/*++
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Routine Description:
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This service deletes the specified file.
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Arguments:
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ObjectAttributes - Supplies the attributes to be used for file object (name,
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SECURITY_DESCRIPTOR, etc.)
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Return Value:
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The status returned is the final completion status of the operation.
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--*/
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{
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KPROCESSOR_MODE requestorMode;
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NTSTATUS status;
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OPEN_PACKET openPacket;
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DUMMY_FILE_OBJECT localFileObject;
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HANDLE handle;
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PAGED_CODE();
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//
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// Get the previous mode; i.e., the mode of the caller.
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//
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requestorMode = KeGetPreviousMode();
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//
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// Build a parse open packet that tells the parse method to open the file
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// for open for delete access w/the delete bit set, and then close it.
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//
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RtlZeroMemory( &openPacket, sizeof( OPEN_PACKET ) );
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openPacket.Type = IO_TYPE_OPEN_PACKET;
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openPacket.Size = sizeof( OPEN_PACKET );
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openPacket.CreateOptions = FILE_DELETE_ON_CLOSE;
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openPacket.ShareAccess = (USHORT) FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
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openPacket.Disposition = FILE_OPEN;
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openPacket.DeleteOnly = TRUE;
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openPacket.LocalFileObject = &localFileObject;
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//
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// Update the open count for this process.
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//
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IopUpdateOtherOperationCount();
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//
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// Open the object by its name. Because of the special DeleteOnly flag
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// set in the open packet, the parse routine will open the file, and
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// then realize that it is only deleting the file, and will therefore
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// immediately dereference the file. This will cause the cleanup and
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// the close to be sent to the file system, thus causing the file to
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// be deleted.
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//
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status = ObOpenObjectByName( ObjectAttributes,
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(POBJECT_TYPE) NULL,
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requestorMode,
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NULL,
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DELETE,
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&openPacket,
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&handle );
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//
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// The operation is successful if the parse check field of the open packet
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// indicates that the parse routine was actually invoked, and the final
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// status field of the packet is set to success.
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//
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if (openPacket.ParseCheck != OPEN_PACKET_PATTERN) {
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return status;
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} else {
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return openPacket.FinalStatus;
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}
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}
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NTSTATUS
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NtFlushBuffersFile(
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IN HANDLE FileHandle,
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OUT PIO_STATUS_BLOCK IoStatusBlock
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)
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/*++
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Routine Description:
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This service causes all buffered data to the file to be written.
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Arguments:
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FileHandle - Supplies a handle to the file whose buffers should be flushed.
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IoStatusBlock - Address of the caller's I/O status block.
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Return Value:
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The status returned is the final completion status of the operation.
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--*/
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{
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PIRP irp;
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NTSTATUS status;
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PFILE_OBJECT fileObject;
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PDEVICE_OBJECT deviceObject;
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PKEVENT event;
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KPROCESSOR_MODE requestorMode;
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PIO_STACK_LOCATION irpSp;
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IO_STATUS_BLOCK localIoStatus;
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OBJECT_HANDLE_INFORMATION objectHandleInformation;
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BOOLEAN synchronousIo;
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PAGED_CODE();
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//
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// Get the previous mode; i.e., the mode of the caller.
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//
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requestorMode = KeGetPreviousMode();
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if (requestorMode != KernelMode) {
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//
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// The caller's access mode is not kernel so probe each of the arguments
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// and capture them as necessary. If any failures occur, the condition
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// handler will be invoked to handle them. It will simply cleanup and
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// return an access violation status code back to the system service
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// dispatcher.
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//
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try {
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//
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// The IoStatusBlock parameter must be writeable by the caller.
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//
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ProbeForWriteIoStatus( IoStatusBlock );
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} except(EXCEPTION_EXECUTE_HANDLER) {
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//
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// An exception was incurred attempting to probe the caller's
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// I/O status block. Simply return an appropriate error status
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// code.
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//
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return GetExceptionCode();
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}
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}
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//
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// There were no blatant errors so far, so reference the file object so
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// the target device object can be found. Note that if the handle does
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// not refer to a file object, or if the caller does not have the required
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// access to the file, then it will fail.
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//
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status = ObReferenceObjectByHandle( FileHandle,
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0,
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IoFileObjectType,
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requestorMode,
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(PVOID *) &fileObject,
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&objectHandleInformation );
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if (!NT_SUCCESS( status )) {
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return status;
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}
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//
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// Ensure that the caller has either WRITE or APPEND access to the file
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// before allowing this call to continue. This is especially important
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// if the caller opened a volume, where a flush operation may flush more
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// than what this opener has written to buffers. Note however that if
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// this is a pipe, then the APPEND access cannot be made since this
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// access code is overlaid with the CREATE_PIPE_INSTANCE access.
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//
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if (SeComputeGrantedAccesses( objectHandleInformation.GrantedAccess,
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(!(fileObject->Flags & FO_NAMED_PIPE) ?
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FILE_APPEND_DATA : 0) |
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FILE_WRITE_DATA ) == 0) {
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ObDereferenceObject( fileObject );
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return STATUS_ACCESS_DENIED;
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}
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//
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// Make a special check here to determine whether this is a synchronous
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// I/O operation. If it is, then wait here until the file is owned by
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// the current thread. If this is not a (serialized) synchronous I/O
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// operation, then allocate and initialize the local event.
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//
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if (fileObject->Flags & FO_SYNCHRONOUS_IO) {
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BOOLEAN interrupted;
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if (!IopAcquireFastLock( fileObject )) {
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status = IopAcquireFileObjectLock( fileObject,
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requestorMode,
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(BOOLEAN) ((fileObject->Flags & FO_ALERTABLE_IO) != 0),
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&interrupted );
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if (interrupted) {
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ObDereferenceObject( fileObject );
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return status;
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}
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}
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synchronousIo = TRUE;
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} else {
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//
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// This is a synchronous API being invoked for a file that is opened
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// for asynchronous I/O. This means that this system service is
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// to synchronize the completion of the operation before returning
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// to the caller. A local event is used to do this.
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//
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event = ExAllocatePool( NonPagedPool, sizeof( KEVENT ) );
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if (event == NULL) {
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ObDereferenceObject( fileObject );
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return STATUS_INSUFFICIENT_RESOURCES;
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}
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KeInitializeEvent( event, SynchronizationEvent, FALSE );
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synchronousIo = FALSE;
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}
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//
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// Set the file object to the Not-Signaled state.
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//
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KeClearEvent( &fileObject->Event );
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//
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// Get the address of the target device object.
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//
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deviceObject = IoGetRelatedDeviceObject( fileObject );
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//
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// Allocate and initialize the I/O Request Packet (IRP) for this operation.
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// The allocation is performed with an exception handler in case the
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// caller does not have enough quota to allocate the packet.
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irp = IoAllocateIrp( deviceObject->StackSize, TRUE );
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if (!irp) {
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//
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// An exception was incurred while attempting to allocate the IRP.
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// Cleanup and return an appropriate error status code.
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//
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if (!(fileObject->Flags & FO_SYNCHRONOUS_IO)) {
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ExFreePool( event );
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}
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IopAllocateIrpCleanup( fileObject, (PKEVENT) NULL );
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return STATUS_INSUFFICIENT_RESOURCES;
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}
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irp->Tail.Overlay.OriginalFileObject = fileObject;
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irp->Tail.Overlay.Thread = PsGetCurrentThread();
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irp->RequestorMode = requestorMode;
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//
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// Fill in the service independent parameters in the IRP.
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//
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if (synchronousIo) {
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irp->UserEvent = (PKEVENT) NULL;
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irp->UserIosb = IoStatusBlock;
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} else {
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irp->UserEvent = event;
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irp->UserIosb = &localIoStatus;
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irp->Flags = IRP_SYNCHRONOUS_API;
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}
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irp->Overlay.AsynchronousParameters.UserApcRoutine = (PIO_APC_ROUTINE) NULL;
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//
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// Get a pointer to the stack location for the first driver. This is used
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// to pass the original function codes and parameters.
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//
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irpSp = IoGetNextIrpStackLocation( irp );
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irpSp->MajorFunction = IRP_MJ_FLUSH_BUFFERS;
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irpSp->FileObject = fileObject;
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//
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// Queue the packet, call the driver, and synchronize appopriately with
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// I/O completion.
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//
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status = IopSynchronousServiceTail( deviceObject,
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irp,
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fileObject,
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FALSE,
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requestorMode,
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synchronousIo,
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OtherTransfer );
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//
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// If the file for this operation was not opened for synchronous I/O, then
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// synchronization of completion of the I/O operation has not yet occurred
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// since the allocated event must be used for synchronous APIs on files
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||
// opened for asynchronous I/O. Synchronize the completion of the I/O
|
||
// operation now.
|
||
//
|
||
|
||
if (!synchronousIo) {
|
||
|
||
status = IopSynchronousApiServiceTail( status,
|
||
event,
|
||
irp,
|
||
requestorMode,
|
||
&localIoStatus,
|
||
IoStatusBlock );
|
||
}
|
||
|
||
return status;
|
||
}
|
||
|
||
NTSTATUS
|
||
NtQueryAttributesFile(
|
||
IN POBJECT_ATTRIBUTES ObjectAttributes,
|
||
OUT PFILE_BASIC_INFORMATION FileInformation
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This service queries the basic attributes information for a specified file.
|
||
|
||
Arguments:
|
||
|
||
ObjectAttributes - Supplies the attributes to be used for file object (name,
|
||
SECURITY_DESCRIPTOR, etc.)
|
||
|
||
FileInformation - Supplies an output buffer to receive the returned file
|
||
attributes information.
|
||
|
||
Return Value:
|
||
|
||
The status returned is the final completion status of the operation.
|
||
|
||
--*/
|
||
|
||
{
|
||
KPROCESSOR_MODE requestorMode;
|
||
NTSTATUS status;
|
||
OPEN_PACKET openPacket;
|
||
DUMMY_FILE_OBJECT localFileObject;
|
||
FILE_NETWORK_OPEN_INFORMATION networkInformation;
|
||
HANDLE handle;
|
||
|
||
PAGED_CODE();
|
||
|
||
//
|
||
// Get the previous mode; i.e., the mode of the caller.
|
||
//
|
||
|
||
requestorMode = KeGetPreviousMode();
|
||
|
||
if (requestorMode != KernelMode) {
|
||
|
||
try {
|
||
|
||
//
|
||
// The caller's mode is not kernel, so probe the output buffer.
|
||
//
|
||
|
||
ProbeForWrite( FileInformation,
|
||
sizeof( FILE_BASIC_INFORMATION ),
|
||
sizeof( ULONG ));
|
||
|
||
} except(EXCEPTION_EXECUTE_HANDLER) {
|
||
|
||
//
|
||
// An exception was incurred while probing the caller's parameters.
|
||
// Simply return an appropriate error status code.
|
||
//
|
||
|
||
return GetExceptionCode();
|
||
}
|
||
}
|
||
|
||
//
|
||
// Build a parse open packet that tells the parse method to open the file,
|
||
// query the file's basic attributes, and close the file.
|
||
//
|
||
|
||
RtlZeroMemory( &openPacket, sizeof( OPEN_PACKET ) );
|
||
|
||
openPacket.Type = IO_TYPE_OPEN_PACKET;
|
||
openPacket.Size = sizeof( OPEN_PACKET );
|
||
openPacket.ShareAccess = (USHORT) FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
|
||
openPacket.Disposition = FILE_OPEN;
|
||
openPacket.BasicInformation = FileInformation;
|
||
openPacket.NetworkInformation = &networkInformation;
|
||
openPacket.QueryOnly = TRUE;
|
||
openPacket.LocalFileObject = &localFileObject;
|
||
|
||
//
|
||
// Update the open count for this process.
|
||
//
|
||
|
||
IopUpdateOtherOperationCount();
|
||
|
||
//
|
||
// Open the object by its name. Because of the special QueryOnly flag set
|
||
// in the open packet, the parse routine will open the file, and then
|
||
// realize that it is only performing a query. It will therefore perform
|
||
// the query, and immediately close the file.
|
||
//
|
||
|
||
status = ObOpenObjectByName( ObjectAttributes,
|
||
(POBJECT_TYPE) NULL,
|
||
requestorMode,
|
||
NULL,
|
||
FILE_READ_ATTRIBUTES,
|
||
&openPacket,
|
||
&handle );
|
||
|
||
//
|
||
// The operation is successful if the parse check field of the open packet
|
||
// indicates that the parse routine was actually invoked, and the final
|
||
// status field of the packet is set to success.
|
||
//
|
||
|
||
if (openPacket.ParseCheck != OPEN_PACKET_PATTERN) {
|
||
return status;
|
||
} else {
|
||
return openPacket.FinalStatus;
|
||
}
|
||
}
|
||
|
||
NTSTATUS
|
||
NtQueryFullAttributesFile(
|
||
IN POBJECT_ATTRIBUTES ObjectAttributes,
|
||
OUT PFILE_NETWORK_OPEN_INFORMATION FileInformation
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This service queries the network attributes information for a specified
|
||
file.
|
||
|
||
Arguments:
|
||
|
||
ObjectAttributes - Supplies the attributes to be used for file object (name,
|
||
SECURITY_DESCRIPTOR, etc.)
|
||
|
||
FileInformation - Supplies an output buffer to receive the returned file
|
||
attributes information.
|
||
|
||
Return Value:
|
||
|
||
The status returned is the final completion status of the operation.
|
||
|
||
--*/
|
||
|
||
{
|
||
KPROCESSOR_MODE requestorMode;
|
||
NTSTATUS status;
|
||
OPEN_PACKET openPacket;
|
||
DUMMY_FILE_OBJECT localFileObject;
|
||
FILE_NETWORK_OPEN_INFORMATION networkInformation;
|
||
HANDLE handle;
|
||
|
||
PAGED_CODE();
|
||
|
||
//
|
||
// Get the previous mode; i.e., the mode of the caller.
|
||
//
|
||
|
||
requestorMode = KeGetPreviousMode();
|
||
|
||
if (requestorMode != KernelMode) {
|
||
|
||
try {
|
||
|
||
//
|
||
// The caller's mode is not kernel, so probe the output buffer.
|
||
//
|
||
|
||
ProbeForWrite( FileInformation,
|
||
sizeof( FILE_NETWORK_OPEN_INFORMATION ),
|
||
#if defined(_X86_)
|
||
sizeof( LONG ));
|
||
#else
|
||
sizeof( LONGLONG ));
|
||
#endif // defined(_X86_)
|
||
|
||
} except(EXCEPTION_EXECUTE_HANDLER) {
|
||
|
||
//
|
||
// An exception was incurred while probing the caller's parameters.
|
||
// Simply return an appropriate error status code.
|
||
//
|
||
|
||
return GetExceptionCode();
|
||
}
|
||
}
|
||
|
||
//
|
||
// Build a parse open packet that tells the parse method to open the file,
|
||
// query the file's full attributes, and close the file.
|
||
//
|
||
|
||
RtlZeroMemory( &openPacket, sizeof( OPEN_PACKET ) );
|
||
|
||
openPacket.Type = IO_TYPE_OPEN_PACKET;
|
||
openPacket.Size = sizeof( OPEN_PACKET );
|
||
openPacket.ShareAccess = (USHORT) FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
|
||
openPacket.Disposition = FILE_OPEN;
|
||
openPacket.QueryOnly = TRUE;
|
||
openPacket.FullAttributes = TRUE;
|
||
openPacket.LocalFileObject = &localFileObject;
|
||
if (requestorMode != KernelMode) {
|
||
openPacket.NetworkInformation = &networkInformation;
|
||
} else {
|
||
openPacket.NetworkInformation = FileInformation;
|
||
}
|
||
|
||
//
|
||
// Update the open count for this process.
|
||
//
|
||
|
||
IopUpdateOtherOperationCount();
|
||
|
||
//
|
||
// Open the object by its name. Because of the special QueryOnly flag set
|
||
// in the open packet, the parse routine will open the file, and then
|
||
// realize that it is only performing a query. It will therefore perform
|
||
// the query, and immediately close the file.
|
||
//
|
||
|
||
status = ObOpenObjectByName( ObjectAttributes,
|
||
(POBJECT_TYPE) NULL,
|
||
requestorMode,
|
||
NULL,
|
||
FILE_READ_ATTRIBUTES,
|
||
&openPacket,
|
||
&handle );
|
||
|
||
//
|
||
// The operation is successful if the parse check field of the open packet
|
||
// indicates that the parse routine was actually invoked, and the final
|
||
// status field of the packet is set to success.
|
||
//
|
||
|
||
if (openPacket.ParseCheck != OPEN_PACKET_PATTERN) {
|
||
return status;
|
||
} else {
|
||
status = openPacket.FinalStatus;
|
||
}
|
||
|
||
if (NT_SUCCESS( status )) {
|
||
if (requestorMode != KernelMode) {
|
||
try {
|
||
|
||
//
|
||
// The query worked, so copy the returned information to the
|
||
// caller's output buffer.
|
||
//
|
||
|
||
RtlMoveMemory( FileInformation,
|
||
&networkInformation,
|
||
sizeof( FILE_NETWORK_OPEN_INFORMATION ) );
|
||
|
||
} except(EXCEPTION_EXECUTE_HANDLER) {
|
||
status = GetExceptionCode();
|
||
}
|
||
}
|
||
}
|
||
|
||
return status;
|
||
}
|