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windows-nt/Source/XPSP1/NT/net/rras/ip/ipinip/driver.c

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/*++
Copyright (c) 1995 Microsoft Corporation
Module Name:
net\ip\ipinip\driver.c
Abstract:
IP in IP driver shell
Revision History:
Gurdeep Singh Pall 8/2/95 Created
--*/
#define __FILE_SIG__ DRIVER_SIG
#include "inc.h"
#pragma alloc_text(INIT, DriverEntry)
NTSTATUS
DriverEntry(
IN PDRIVER_OBJECT DriverObject,
IN PUNICODE_STRING RegistryPath
)
/*++
Routine Description
Installable driver initialization entry point.
This entry point is called directly by the I/O system and must be named
"Driver Entry"
The function is discardable since it is only called once
On checked builds we read some values from registry and initialize the
debugging
We create a DEVICE_OBJECT for ourselves to field the IOCTLs, create
a DOS name for the device and initialize some events and spinlocks
Locks
None
Arguments
DriverObject Pointer to I/O subsystem created driver object
RegistryPath Points to driver key in HKLM\CCS\Services...
Return Value
STATUS_SUCCESS if everything went as planned or some status code from
ntstatus.h
--*/
{
NTSTATUS nStatus;
PDEVICE_OBJECT pDeviceObject;
UNICODE_STRING usDeviceName;
DWORD dwVal, i;
HANDLE hRegKey;
WCHAR ParametersRegistryPath[] =
L"\\Registry\\Machine\\System\\CurrentControlSet\\Services\\IpInIp\\Parameters";
RtInitializeDebug();
//
// Read the registry for parameters
//
nStatus = OpenRegKey(&hRegKey,
ParametersRegistryPath);
if(nStatus is STATUS_SUCCESS)
{
#if RT_TRACE_DEBUG
nStatus = GetRegDWORDValue(hRegKey,
L"DebugLevel",
&dwVal);
if(nStatus is STATUS_SUCCESS)
{
g_byDebugLevel = (BYTE)dwVal;
}
nStatus = GetRegDWORDValue(hRegKey,
L"DebugComp",
&dwVal);
if(nStatus is STATUS_SUCCESS)
{
g_fDebugComp = dwVal;
}
#endif
#if DBG
nStatus = GetRegDWORDValue(hRegKey,
L"DebugBreak",
&dwVal);
if((nStatus is STATUS_SUCCESS) and
(dwVal is 1))
{
DbgBreakPoint();
}
#endif
ZwClose(hRegKey);
}
TraceEnter(GLOBAL, "DriverEntry");
//
// Initialize some globals
//
g_dwDriverState = DRIVER_STOPPED;
g_ulNumThreads = 0;
g_ulNumOpens = 0;
g_hIpRegistration = NULL;
//
// Create the device
//
RtlInitUnicodeString(&usDeviceName,
DD_IPINIP_DEVICE_NAME);
nStatus = IoCreateDevice(DriverObject,
0,
&usDeviceName,
FILE_DEVICE_NETWORK,
FILE_DEVICE_SECURE_OPEN,
FALSE,
&pDeviceObject);
if (!NT_SUCCESS(nStatus))
{
Trace(GLOBAL, ERROR,
("DriverEntry: Cant create device object %ws, status %lx.\n",
DD_IPINIP_DEVICE_NAME,
nStatus));
TraceLeave(GLOBAL, "DriverEntry");
return nStatus;
}
//
// Initialize the driver object
//
DriverObject->DriverUnload = IpIpUnload;
DriverObject->FastIoDispatch = NULL;
for(i=0; i <= IRP_MJ_MAXIMUM_FUNCTION; i++)
{
DriverObject->MajorFunction[i] = IpIpDispatch;
}
if(!SetupExternalName(&usDeviceName,
WIN32_IPINIP_SYMBOLIC_LINK,
TRUE))
{
Trace(GLOBAL,ERROR,
("DriverEntry: Win32 device name could not be created\n"));
IoDeleteDevice(pDeviceObject);
TraceLeave(GLOBAL, "DriverEntry");
return STATUS_UNSUCCESSFUL;
}
//
// Lock and event needed to keep track of threads in the driver
//
RtInitializeSpinLock(&g_rlStateLock);
KeInitializeEvent(&(g_keStateEvent),
SynchronizationEvent,
FALSE);
//
// Many threads may be waiting for us to start so this needs to be a
// NotificationEvent
//
KeInitializeEvent(&(g_keStartEvent),
NotificationEvent,
FALSE);
InitRwLock(&g_rwlTunnelLock);
InitializeListHead(&g_leTunnelList);
InitializeListHead(&g_lePendingMessageList);
InitializeListHead(&g_lePendingIrpList);
//
// Register with IP
//
nStatus = RegisterWithIp();
if(nStatus isnot STATUS_SUCCESS)
{
Trace(GLOBAL, ERROR,
("DriverEntry: RegisterWithIP failed\n"));
IoDeleteDevice(pDeviceObject);
TraceLeave(GLOBAL, "InitializeDriver");
return FALSE;
}
g_pIpIpDevice = pDeviceObject;
TraceLeave(GLOBAL, "DriverEntry");
return nStatus;
}
#pragma alloc_text(PAGE, IpIpDispatch)
NTSTATUS
IpIpDispatch(
IN PDEVICE_OBJECT DeviceObject,
IN PIRP Irp
)
/*++
Routine Description
The functions which handles the IRPs sent to the driver
Locks
This code is PAGEABLE so can not acquire locks
Arguments
Return Value
STATUS_SUCCESS
--*/
{
PIO_STACK_LOCATION irpStack;
ULONG ulInputBuffLen;
ULONG ulOutputBuffLen;
ULONG ioControlCode;
NTSTATUS nStatus;
KIRQL kiIrql;
LARGE_INTEGER liTimeOut;
BOOLEAN bEnter;
PAGED_CODE();
TraceEnter(GLOBAL, "IpIpDispatch");
Irp->IoStatus.Information = 0;
//
// Get a pointer to the current location in the Irp. This is where
// the function codes and parameters are located.
//
irpStack = IoGetCurrentIrpStackLocation(Irp);
//
// Get the pointer to the input/output buffer and it's length
//
ulInputBuffLen = irpStack->Parameters.DeviceIoControl.InputBufferLength;
ulOutputBuffLen = irpStack->Parameters.DeviceIoControl.OutputBufferLength;
switch (irpStack->MajorFunction)
{
case IRP_MJ_CREATE:
{
Trace(GLOBAL, TRACE,
("IpIpDispatch: IRP_MJ_CREATE\n"));
//
// We start the driver when the first CreateFile is done
// But we need to serialize the Creates
//
nStatus = StartDriver();
if(nStatus is STATUS_PENDING)
{
//
// Means someone is trying to start the driver
// We wait for some time (since we are at PASSIVE)
//
liTimeOut.QuadPart = START_TIMEOUT;
nStatus = KeWaitForSingleObject(&g_keStartEvent,
UserRequest,
KernelMode,
FALSE,
&liTimeOut);
if(nStatus isnot STATUS_SUCCESS)
{
//
// We timed out - bad things are happening here
//
Trace(GLOBAL, ERROR,
("IpIpDispatch: Timeout trying to start driver\n"));
nStatus = STATUS_UNSUCCESSFUL;
}
else
{
//
// Make sure the driver actually started
//
bEnter = EnterDriverCode();
ExitDriverCode();
if(!bEnter)
{
Trace(GLOBAL, ERROR,
("IpIpDispatch: Wait successful, but unable to start driver\n"));
nStatus = STATUS_UNSUCCESSFUL;
}
}
}
break;
}
case IRP_MJ_CLOSE:
{
Trace(GLOBAL, TRACE,
("IpIpDispatch: IRP_MJ_CLOSE\n"));
//
// We handle cleanup and not close
//
nStatus = STATUS_SUCCESS;
break;
}
case IRP_MJ_CLEANUP:
{
Trace(GLOBAL, TRACE,
("IpIpDispatch: IRP_MJ_CLEANUP\n"));
StopDriver();
nStatus = STATUS_SUCCESS;
break;
}
case IRP_MJ_DEVICE_CONTROL:
{
DWORD dwState;
ULONG ulControl;
//
// Get the control code and our code
//
ioControlCode = irpStack->Parameters.DeviceIoControl.IoControlCode;
//
// If the driver is stopping, dont process anything else
//
bEnter = EnterDriverCode();
if(!bEnter)
{
Trace(GLOBAL, ERROR,
("IpIpDispatch: Driver is not started\n"));
nStatus = STATUS_NO_SUCH_DEVICE;
break;
}
switch(ioControlCode)
{
case IOCTL_IPINIP_CREATE_TUNNEL:
{
nStatus = AddTunnelInterface(Irp,
ulInputBuffLen,
ulOutputBuffLen);
break;
}
case IOCTL_IPINIP_DELETE_TUNNEL:
{
nStatus = DeleteTunnelInterface(Irp,
ulInputBuffLen,
ulOutputBuffLen);
break;
}
case IOCTL_IPINIP_SET_TUNNEL_INFO:
{
nStatus = SetTunnelInfo(Irp,
ulInputBuffLen,
ulOutputBuffLen);
break;
}
case IOCTL_IPINIP_GET_TUNNEL_TABLE:
{
nStatus = GetTunnelTable(Irp,
ulInputBuffLen,
ulOutputBuffLen);
break;
}
case IOCTL_IPINIP_NOTIFICATION:
{
nStatus = ProcessNotification(Irp,
ulInputBuffLen,
ulOutputBuffLen);
break;
}
default:
{
Trace(GLOBAL, ERROR,
("IpIpDispatch: Unknown IRP_MJ_DEVICE_CONTROL %x\n",
ioControlCode));
nStatus = STATUS_INVALID_PARAMETER;
}
}
ExitDriverCode();
break;
}
default:
{
Trace(GLOBAL, ERROR,
("IpIpDispatch: Unknown IRP_MJ_XX - %x\n",
irpStack->MajorFunction));
nStatus = STATUS_INVALID_PARAMETER;
break;
}
}
if(nStatus isnot STATUS_PENDING)
{
Irp->IoStatus.Status = nStatus;
IoCompleteRequest(Irp,
IO_NETWORK_INCREMENT);
}
TraceLeave(GLOBAL, "IpIpDispatch");
return nStatus;
}
VOID
IpIpUnload(
PDRIVER_OBJECT DriverObject
)
/*++
Routine Description
Called by the I/O subsystem, when our driver is being unloaded
Locks
Arguments
Return Value
None
--*/
{
UNICODE_STRING usDeviceName;
BOOLEAN bWait;
KIRQL kiIrql;
NDIS_STATUS nsStatus;
NTSTATUS nStatus;
TraceEnter(GLOBAL,"IpIpUnload");
//
// The driver must have stopped before it came here
//
RtAssert(g_dwDriverState is DRIVER_STOPPED);
RemoveAllTunnels();
//
// Clear out IP's state
//
DeregisterWithIp();
//
// Remove ourself from NT and DOS namespace
//
RtlInitUnicodeString(&usDeviceName,
DD_IPINIP_DEVICE_NAME);
SetupExternalName(&usDeviceName,
WIN32_IPINIP_SYMBOLIC_LINK,
FALSE);
//
// Clean out address blocks, if any
//
while(!IsListEmpty(&g_leAddressList))
{
PADDRESS_BLOCK pAddrBlock;
PLIST_ENTRY pleNode;
pleNode = RemoveHeadList(&g_leAddressList);
pAddrBlock = CONTAINING_RECORD(pleNode,
ADDRESS_BLOCK,
leAddressLink);
RtFree(pAddrBlock);
}
//
// See if we have any free memory
//
RtAuditMemory();
//
// Delete the device object
//
IoDeleteDevice(DriverObject->DeviceObject);
TraceLeave(GLOBAL,"IpIpUnload");
}
#pragma alloc_text(PAGE, SetupExternalName)
BOOLEAN
SetupExternalName(
PUNICODE_STRING pusNtName,
PWCHAR pwcDosName,
BOOLEAN bCreate
)
/*++
Routine Description
Setup or delete a symbolic link to DOS namespace
Locks
Arguments
pusNtName Name in NT space
pwcDosName Name in DOS space
bCreate Set to TRUE to create, FALSE to delete
Return Value
TRUE if successful
FALSE otherwise
--*/
{
UNICODE_STRING usSymbolicLinkName;
WCHAR rgwcBuffer[100];
PAGED_CODE();
//
// Form the full symbolic link name we wish to create.
//
usSymbolicLinkName.Buffer = rgwcBuffer;
RtlInitUnicodeString(&usSymbolicLinkName,
pwcDosName);
if(bCreate)
{
if(!NT_SUCCESS(IoCreateSymbolicLink(&usSymbolicLinkName,
pusNtName)))
{
return FALSE;
}
}
else
{
IoDeleteSymbolicLink(&usSymbolicLinkName);
}
return TRUE;
}
NTSTATUS
StartDriver(
VOID
)
/*++
Routine Description
Main routine to start the driver. We call this when we get CREATE irp
If the driver has started, we return success. If someone is starting the
driver, we return pending. The caller then needs to wait on g_keStartEvent
We try and start the driver. If all goes well, we set the event and
everyone parties on from there
Locks
The function takes the g_rlStateLock to check the state and increment
the number of CREATEs it has received (open handles)
Arguments
None
Return Value
STATUS_SUCCESS if the driver started
STATUS_PENDING if the driver is being started by some other thread's
--*/
{
KIRQL kiOldIrql;
NTSTATUS nStatus;
DWORD dwState;
OPEN_CONTEXT TdixContext;
WORK_QUEUE_ITEM WorkItem;
KEVENT keTempEvent;
TraceEnter(GLOBAL, "StartDriver");
RtAcquireSpinLock(&g_rlStateLock,
&kiOldIrql);
g_ulNumOpens++;
if(g_ulNumOpens isnot 1)
{
if(g_dwDriverState is DRIVER_STARTING)
{
//
// Someone is trying to start the driver
//
Trace(GLOBAL, INFO,
("StartDriver: Driver is being started by someone else\n"));
nStatus = STATUS_PENDING;
}
else
{
//
// If we are not the first CreateFile, and the driver is not
// starting then the driver must already be running
//
RtAssert(g_dwDriverState is DRIVER_STARTED);
nStatus = STATUS_SUCCESS;
}
RtReleaseSpinLock(&g_rlStateLock,
kiOldIrql);
return nStatus;
}
//
// The first CreateFile
//
RtAssert(g_dwDriverState is DRIVER_STOPPED);
//
// Set the state to starting, release the lock and actually start
// the driver
//
g_dwDriverState = DRIVER_STARTING;
RtReleaseSpinLock(&g_rlStateLock,
kiOldIrql);
dwState = DRIVER_STARTED;
//
// Initialize the event and work item to start TDI
//
KeInitializeEvent(&keTempEvent,
SynchronizationEvent,
FALSE);
TdixContext.pkeEvent = &keTempEvent;
ExInitializeWorkItem(&WorkItem,
TdixInitialize,
&TdixContext);
//
// Start TDI in the system context so that we the handles are not
// associated with the current process
//
ExQueueWorkItem(&WorkItem,
DelayedWorkQueue);
//
// Wait for TDI to get done
//
nStatus = KeWaitForSingleObject(TdixContext.pkeEvent,
UserRequest,
KernelMode,
FALSE,
NULL);
if((nStatus isnot STATUS_SUCCESS) or
(TdixContext.nStatus isnot STATUS_SUCCESS))
{
Trace(GLOBAL, ERROR,
("StartDriver: TdixInitialize failed with %x %x\n",
nStatus, TdixContext.nStatus));
dwState = DRIVER_STOPPED;
}
if(dwState is DRIVER_STARTED)
{
LARGE_INTEGER liDueTime;
KeInitializeDpc(&g_kdTimerDpc,
IpIpTimerRoutine,
NULL);
KeInitializeTimer(&g_ktTimer);
liDueTime = RtlEnlargedUnsignedMultiply(TIMER_IN_MILLISECS,
SYS_UNITS_IN_ONE_MILLISEC);
liDueTime = RtlLargeIntegerNegate(liDueTime);
KeSetTimerEx(&g_ktTimer,
liDueTime,
0,
&g_kdTimerDpc);
}
RtAcquireSpinLock(&g_rlStateLock,
&kiOldIrql);
g_dwDriverState = dwState;
//
// Someone may have been waiting for us to start
//
KeSetEvent(&g_keStartEvent,
0,
FALSE);
RtReleaseSpinLock(&g_rlStateLock,
kiOldIrql);
TraceLeave(GLOBAL, "StartDriver");
return nStatus;
}
VOID
StopDriver(
VOID
)
/*++
Routine Description
Called when we get an IRP_MJ_CLEANUP. It is the inverse of StartDriver
If this is the last thread, we set the state to STOPPED and wait till
all threads of execution have exited the driver.
We then clean out resources
Locks
The function takes the g_rlStateLock
Arguments
None
Return Value
None
--*/
{
KIRQL kiOldIrql;
NTSTATUS nStatus;
BOOLEAN bWait;
ULONG i;
OPEN_CONTEXT TdixContext;
WORK_QUEUE_ITEM WorkItem;
KEVENT keTempEvent;
PIO_WORKITEM pIoWorkItem;
TraceEnter(GLOBAL, "StopDriver");
//
// Acquire the state and ref count spin lock
//
RtAcquireSpinLock(&g_rlStateLock,
&kiOldIrql);
g_ulNumOpens--;
if(g_ulNumOpens isnot 0)
{
//
// Other people still around
//
RtReleaseSpinLock(&g_rlStateLock,
kiOldIrql);
TraceLeave(GLOBAL, "StopDriver");
return;
}
//
// Set the state to stopping. Any reader will
// return on seeing this. So essentially we are not
// allowing any new readers in
//
g_dwDriverState = DRIVER_STOPPED;
//
// However there may already be readers. We wait
// if there are any
//
bWait = (g_ulNumThreads > 0);
RtReleaseSpinLock(&g_rlStateLock,
kiOldIrql);
//
// Now do a wait. We can do this since we are at PASSIVE
//
if(bWait)
{
Trace(GLOBAL, INFO,
("StopDriver: Need to wait for threads to exit\n"));
do
{
nStatus = KeWaitForSingleObject(&g_keStateEvent,
Executive,
KernelMode,
FALSE,
NULL);
}while((nStatus is STATUS_USER_APC) or
(nStatus is STATUS_ALERTED) or
(nStatus is STATUS_TIMEOUT));
}
//
// Undo the timer
//
i = 0;
while(KeCancelTimer(&g_ktTimer) is FALSE)
{
LARGE_INTEGER liTimeOut;
//
// Hmm, timer was not in the system queue.
// Set the wait to 2, 4, 6... secs
//
liTimeOut.QuadPart = (LONGLONG)((i + 1) * 2 * 1000 * 1000 * 10 * -1);
KeDelayExecutionThread(UserMode,
FALSE,
&liTimeOut);
i++;
}
//
// Initialize the event and work item to stop TDI
//
KeInitializeEvent(&keTempEvent,
SynchronizationEvent,
FALSE);
TdixContext.pkeEvent = &keTempEvent;
pIoWorkItem = IoAllocateWorkItem(g_pIpIpDevice);
//
// Must have a work item - no failure code path
//
RtAssert(pIoWorkItem);
IoQueueWorkItem(pIoWorkItem,
TdixDeinitialize,
DelayedWorkQueue,
&TdixContext);
//
// Wait for TDI to get done
//
nStatus = KeWaitForSingleObject(TdixContext.pkeEvent,
UserRequest,
KernelMode,
FALSE,
NULL);
RtAssert(nStatus is STATUS_SUCCESS);
IoFreeWorkItem(pIoWorkItem);
//
// Cleanup all resources
//
while(!IsListEmpty(&g_lePendingMessageList))
{
PLIST_ENTRY pleNode;
PPENDING_MESSAGE pMessage;
//
// We have some old info
// Remove it off the pending list
//
pleNode = RemoveHeadList(&g_lePendingMessageList);
//
// Get a pointer to the structure
//
pMessage = CONTAINING_RECORD(pleNode,
PENDING_MESSAGE,
leMessageLink);
//
// Free the allocated message
//
FreeMessage(pMessage);
}
ClearPendingIrps();
TraceLeave(GLOBAL, "StopDriver");
}
NTSTATUS
RegisterWithIp(
VOID
)
/*++
Routine Description
Registers the ARP module with IP
Locks
Arguments
Return Value
--*/
{
NDIS_STRING nsIpIpName;
WCHAR pwszName[] = IPINIP_ARP_NAME;
IP_STATUS Status;
IPInfo Info;
TraceEnter(GLOBAL, "RegisterWithIP");
Status = IPGetInfo(&Info,
sizeof(Info));
if(Status isnot IP_SUCCESS)
{
Trace(GLOBAL, ERROR,
("RegisterWithIp: Couldnt get IPInfo %x\n", Status));
TraceLeave(GLOBAL,
"RegisterWithIP");
return STATUS_UNSUCCESSFUL;
}
g_pfnOpenRce = Info.ipi_openrce;
g_pfnCloseRce = Info.ipi_closerce;
nsIpIpName.MaximumLength = sizeof(pwszName);
nsIpIpName.Length = sizeof(IPINIP_ARP_NAME) - sizeof(WCHAR);
nsIpIpName.Buffer = pwszName;
Status = IPRegisterARP(&nsIpIpName,
IP_ARP_BIND_VERSION,
IpIpBindAdapter,
&g_pfnIpAddInterface,
&g_pfnIpDeleteInterface,
&g_pfnIpBindComplete,
&g_pfnIpAddLink,
&g_pfnIpDeleteLink,
&g_pfnIpChangeIndex,
&g_pfnIpReserveIndex,
&g_pfnIpDereserveIndex,
&g_hIpRegistration);
if(Status isnot IP_SUCCESS)
{
Trace(GLOBAL, ERROR,
("RegisterWithIp: Couldnt register with IP\n"));
TraceLeave(GLOBAL,
"RegisterWithIP");
return STATUS_UNSUCCESSFUL;
}
TraceLeave(GLOBAL,
"RegisterWithIP");
return STATUS_SUCCESS;
}
VOID
DeregisterWithIp(
VOID
)
/*++
Routine Description
DeRegisters the ARP module with IP
Locks
Arguments
Return Value
--*/
{
NTSTATUS nStatus;
TraceEnter(GLOBAL, "DeregisterWithIp");
nStatus = IPDeregisterARP(g_hIpRegistration);
if(nStatus isnot STATUS_SUCCESS)
{
Trace(GLOBAL, ERROR,
("DeregisterWithIp: Couldnt deregister with IP. Error %x\n",
nStatus));
}
g_pfnIpAddInterface = NULL;
g_pfnIpDeleteInterface = NULL;
g_pfnIpBindComplete = NULL;
g_pfnIpRcv = NULL;
g_pfnIpRcvComplete = NULL;
g_pfnIpSendComplete = NULL;
g_pfnIpTDComplete = NULL;
g_pfnIpStatus = NULL;
g_pfnIpRcvPkt = NULL;
g_pfnIpPnp = NULL;
g_hIpRegistration = NULL;
TraceLeave(GLOBAL, "DeregisterWithIp");
}
#pragma alloc_text(PAGE, OpenRegKey)
NTSTATUS
OpenRegKey(
PHANDLE HandlePtr,
PWCHAR KeyName
)
{
NTSTATUS Status;
OBJECT_ATTRIBUTES ObjectAttributes;
UNICODE_STRING UKeyName;
PAGED_CODE();
RtlInitUnicodeString(&UKeyName, KeyName);
RtlZeroMemory(&ObjectAttributes,
sizeof(OBJECT_ATTRIBUTES));
InitializeObjectAttributes(&ObjectAttributes,
&UKeyName,
OBJ_CASE_INSENSITIVE,
NULL,
NULL);
Status = ZwOpenKey(HandlePtr,
KEY_READ,
&ObjectAttributes);
return Status;
}
#pragma alloc_text(PAGE, GetRegDWORDValue)
NTSTATUS
GetRegDWORDValue(
HANDLE KeyHandle,
PWCHAR ValueName,
PULONG ValueData
)
{
NTSTATUS status;
ULONG resultLength;
PKEY_VALUE_FULL_INFORMATION keyValueFullInformation;
UCHAR keybuf[128];
UNICODE_STRING UValueName;
PAGED_CODE();
RtlInitUnicodeString(&UValueName, ValueName);
keyValueFullInformation = (PKEY_VALUE_FULL_INFORMATION)keybuf;
RtlZeroMemory(keyValueFullInformation, sizeof(keyValueFullInformation));
status = ZwQueryValueKey(KeyHandle,
&UValueName,
KeyValueFullInformation,
keyValueFullInformation,
128,
&resultLength);
if (NT_SUCCESS(status)) {
if (keyValueFullInformation->Type != REG_DWORD) {
status = STATUS_INVALID_PARAMETER_MIX;
} else {
*ValueData = *((ULONG UNALIGNED *)((PCHAR)keyValueFullInformation +
keyValueFullInformation->DataOffset));
}
}
return status;
}
BOOLEAN
EnterDriverCode(
VOID
)
{
KIRQL irql;
BOOLEAN bEnter;
RtAcquireSpinLock(&g_rlStateLock,
&irql);
if(g_dwDriverState is DRIVER_STARTED)
{
g_ulNumThreads++;
bEnter = TRUE;
}
else
{
bEnter = FALSE;
}
RtReleaseSpinLock(&g_rlStateLock,
irql);
return bEnter;
}
VOID
ExitDriverCode(
VOID
)
{
KIRQL irql;
RtAcquireSpinLock(&g_rlStateLock,
&irql);
g_ulNumThreads--;
if((g_dwDriverState is DRIVER_STOPPED) and
(g_ulNumThreads is 0))
{
KeSetEvent(&g_keStateEvent,
0,
FALSE);
}
RtReleaseSpinLock(&g_rlStateLock,
irql);
}
VOID
ClearPendingIrps(
VOID
)
/*++
Routine Description:
Called at cleanup time to return any pending IRPs
Locks:
Acquires the IoCancelSpinLock since it controls the pending irp list
Arguments:
None
Return Value:
None
--*/
{
KIRQL irql;
TraceEnter(GLOBAL, "ClearPendingIrps");
IoAcquireCancelSpinLock (&irql);
while(!IsListEmpty(&g_lePendingIrpList))
{
PLIST_ENTRY pleNode;
PIRP pIrp;
pleNode = RemoveHeadList(&g_lePendingIrpList);
pIrp = CONTAINING_RECORD(pleNode,
IRP,
Tail.Overlay.ListEntry);
IoSetCancelRoutine(pIrp,
NULL);
pIrp->IoStatus.Status = STATUS_NO_SUCH_DEVICE;
pIrp->IoStatus.Information = 0;
//
// release lock to complete the IRP
//
IoReleaseCancelSpinLock(irql);
IoCompleteRequest(pIrp,
IO_NETWORK_INCREMENT);
//
// Reaquire the lock
//
IoAcquireCancelSpinLock(&irql);
}
IoReleaseCancelSpinLock(irql);
}
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