通过设备符号连接打开设备 句柄得到设备名_ZwOpenSymbolicLinkObject_ZwQuerySymbolicLinkObject

#pragma PAGEDCODE
NTSTATUS HelloDDKRead(IN PDEVICE_OBJECT pDevObj,IN PIRP pIrp)
{
KdPrint(("DriverB:Enter B HelloDDKRead\n"));
NTSTATUS ntStatus = STATUS_SUCCESS;
UNICODE_STRING DeviceSymbolicLinkName;
RtlInitUnicodeString( &DeviceSymbolicLinkName, L"\\??\\HelloDDKA" );
//初始化objectAttributes
OBJECT_ATTRIBUTES objectAttributes;
InitializeObjectAttributes(&objectAttributes, &DeviceSymbolicLinkName,OBJ_CASE_INSENSITIVE|OBJ_KERNEL_HANDLE, NULL, NULL );
HANDLE hSymbolic;
//设定了FILE_SYNCHRONOUS_IO_NONALERT或者FILE_SYNCHRONOUS_IO_ALERT为同步打开设备
ntStatus = ZwOpenSymbolicLinkObject(&hSymbolic,FILE_ALL_ACCESS,&objectAttributes);
#define UNICODE_SIZE 50
UNICODE_STRING LinkTarget;
LinkTarget.Buffer = (PWSTR)ExAllocatePool(PagedPool,UNICODE_SIZE);
LinkTarget.Length = 0;
LinkTarget.MaximumLength = UNICODE_SIZE;
ULONG unicode_length;
ntStatus = ZwQuerySymbolicLinkObject(hSymbolic,&LinkTarget,&unicode_length);
KdPrint(("DriverB:The device name is %wZ\n",&LinkTarget));//得到符号连接名
InitializeObjectAttributes(&objectAttributes, &LinkTarget,OBJ_CASE_INSENSITIVE, NULL, NULL );
HANDLE hDevice;
IO_STATUS_BLOCK status_block;
//设定了FILE_SYNCHRONOUS_IO_NONALERT或者FILE_SYNCHRONOUS_IO_ALERT为同步打开设备
ntStatus = ZwCreateFile(&hDevice,FILE_READ_ATTRIBUTES|SYNCHRONIZE,&objectAttributes,&status_block,NULL,FILE_ATTRIBUTE_NORMAL,FILE_SHARE_READ,FILE_OPEN_IF,FILE_SYNCHRONOUS_IO_NONALERT,NULL,0);
if (NT_SUCCESS(ntStatus))
{
ZwReadFile(hDevice,NULL,NULL,NULL,&status_block,NULL,0,NULL,NULL);
}
ZwClose(hDevice);
ZwClose(hSymbolic);
ExFreePool(LinkTarget.Buffer);
ntStatus = STATUS_SUCCESS;
// 完成IRP
pIrp->IoStatus.Status = ntStatus;
pIrp->IoStatus.Information = 0;	// bytes xfered
IoCompleteRequest( pIrp, IO_NO_INCREMENT );
KdPrint(("DriverB:Leave B HelloDDKRead\n"));
return ntStatus;
}