// Switchs the current log buffer, saves the contents of old buffer to the log
// file, and prints them out as necessary. This function does not flush the log
// file, so code should call LogpWriteMessageToFile() or ZwFlushBuffersFile()
// later.
_Use_decl_annotations_ static NTSTATUS LogpFlushLogBuffer(LogBufferInfo *info) {
NT_ASSERT(info);
NT_ASSERT(KeGetCurrentIrql() == PASSIVE_LEVEL);
auto status = STATUS_SUCCESS;
// Enter a critical section and acquire a reader lock for info in order to
// write a log file safely.
ExEnterCriticalRegionAndAcquireResourceExclusive(&info->resource);
// Acquire a spin lock for info.log_buffer(s) in order to switch its head
// safely.
KLOCK_QUEUE_HANDLE lock_handle = {};
KeAcquireInStackQueuedSpinLock(&info->spin_lock, &lock_handle);
const auto old_log_buffer = const_cast<char *>(info->log_buffer_head);
if (old_log_buffer[0]) {
info->log_buffer_head = (old_log_buffer == info->log_buffer1)
? info->log_buffer2
: info->log_buffer1;
info->log_buffer_head[0] = '\0';
info->log_buffer_tail = info->log_buffer_head;
}
KeReleaseInStackQueuedSpinLock(&lock_handle);
// Write all log entries in old log buffer.
IO_STATUS_BLOCK io_status = {};
for (auto current_log_entry = old_log_buffer; current_log_entry[0]; /**/) {
// Check the printed bit and clear it
const auto printed_out = LogpIsPrinted(current_log_entry);
LogpSetPrintedBit(current_log_entry, false);
const auto current_log_entry_length = strlen(current_log_entry);
status = ZwWriteFile(info->log_file_handle, nullptr, nullptr, nullptr,
&io_status, current_log_entry,
static_cast<ULONG>(current_log_entry_length), nullptr,
nullptr);
if (!NT_SUCCESS(status)) {
// It could happen when you did not register IRP_SHUTDOWN and call
// LogIrpShutdownHandler() and the system tried to log to a file after
// a file system was unmounted.
LogpDbgBreak();
}
// Print it out if requested and the message is not already printed out
if (!printed_out) {
LogpDoDbgPrint(current_log_entry);
}
current_log_entry += current_log_entry_length + 1;
}
old_log_buffer[0] = '\0';
ExReleaseResourceAndLeaveCriticalRegion(&info->resource);
return status;
}
// Switch the current log buffer and save the contents of old buffer to the log
// file. This function does not flush the log file, so code should call
// LogpWriteMessageToFile() or ZwFlushBuffersFile() later.
EXTERN_C static NTSTATUS LogpWriteLogBufferToFile(
_In_opt_ LogBufferInfo *Info) {
NT_ASSERT(Info);
NT_ASSERT(KeGetCurrentIrql() == PASSIVE_LEVEL);
auto status = STATUS_SUCCESS;
// Enter a critical section and acquire a reader lock for Info in order to
// write a log file safely.
ExEnterCriticalRegionAndAcquireResourceExclusive(&Info->Resource);
// Acquire a spin lock for Info.LogBuffer(s) in order to switch its head
// safely.
const auto irql = KeAcquireSpinLockRaiseToDpc(&Info->SpinLock);
auto oldLogBuffer = const_cast<char *>(Info->LogBufferHead);
if (oldLogBuffer[0]) {
Info->LogBufferHead = (oldLogBuffer == Info->LogBuffer1) ? Info->LogBuffer2
: Info->LogBuffer1;
Info->LogBufferHead[0] = '\0';
Info->LogBufferTail = Info->LogBufferHead;
}
KeReleaseSpinLock(&Info->SpinLock, irql);
// Write all log entries in old log buffer.
IO_STATUS_BLOCK ioStatus = {};
for (auto currentLogEntry = oldLogBuffer; currentLogEntry[0]; /**/) {
const auto currentLogEntryLength = strlen(currentLogEntry);
status =
ZwWriteFile(Info->LogFileHandle, nullptr, nullptr, nullptr, &ioStatus,
currentLogEntry, static_cast<ULONG>(currentLogEntryLength),
nullptr, nullptr);
if (!NT_SUCCESS(status)) {
// It could happen when you did not register IRP_SHUTDOWN and call
// LogIrpShutdownHandler() and the system tried to log to a file after
// a filesystem was unmounted.
DBG_BREAK();
}
currentLogEntry += currentLogEntryLength + 1;
}
oldLogBuffer[0] = '\0';
ExReleaseResourceAndLeaveCriticalRegion(&Info->Resource);
return status;
}
NTSTATUS
DokanDispatchDeviceControl(__in PDEVICE_OBJECT DeviceObject, __in PIRP Irp)
/*++
Routine Description:
This device control dispatcher handles IOCTLs.
Arguments:
DeviceObject - Context for the activity.
Irp - The device control argument block.
Return Value:
NTSTATUS
--*/
{
PDokanVCB vcb;
PDokanDCB dcb;
PIO_STACK_LOCATION irpSp;
NTSTATUS status = STATUS_NOT_IMPLEMENTED;
ULONG controlCode = 0;
ULONG outputLength = 0;
// {DCA0E0A5-D2CA-4f0f-8416-A6414657A77A}
// GUID dokanGUID = { 0xdca0e0a5, 0xd2ca, 0x4f0f, { 0x84, 0x16, 0xa6, 0x41,
// 0x46, 0x57, 0xa7, 0x7a } };
__try {
Irp->IoStatus.Information = 0;
irpSp = IoGetCurrentIrpStackLocation(Irp);
outputLength = irpSp->Parameters.DeviceIoControl.OutputBufferLength;
controlCode = irpSp->Parameters.DeviceIoControl.IoControlCode;
if (controlCode != IOCTL_EVENT_WAIT && controlCode != IOCTL_EVENT_INFO &&
controlCode != IOCTL_KEEPALIVE) {
DDbgPrint("==> DokanDispatchIoControl\n");
DDbgPrint(" ProcessId %lu\n", IoGetRequestorProcessId(Irp));
}
if (DeviceObject->DriverObject == NULL ||
DeviceObject->ReferenceCount < 0) {
status = STATUS_DEVICE_DOES_NOT_EXIST;
__leave;
}
vcb = DeviceObject->DeviceExtension;
PrintIdType(vcb);
if (GetIdentifierType(vcb) == DGL) {
status = GlobalDeviceControl(DeviceObject, Irp);
__leave;
} else if (GetIdentifierType(vcb) == DCB) {
status = DiskDeviceControlWithLock(DeviceObject, Irp);
__leave;
} else if (GetIdentifierType(vcb) != VCB) {
status = STATUS_INVALID_PARAMETER;
__leave;
}
dcb = vcb->Dcb;
switch (irpSp->Parameters.DeviceIoControl.IoControlCode) {
case IOCTL_EVENT_WAIT:
DDbgPrint(" IOCTL_EVENT_WAIT\n");
status = DokanRegisterPendingIrpForEvent(DeviceObject, Irp);
break;
case IOCTL_EVENT_INFO:
// DDbgPrint(" IOCTL_EVENT_INFO\n");
status = DokanCompleteIrp(DeviceObject, Irp);
break;
case IOCTL_EVENT_RELEASE:
DDbgPrint(" IOCTL_EVENT_RELEASE\n");
status = DokanEventRelease(DeviceObject, Irp);
break;
case IOCTL_EVENT_WRITE:
DDbgPrint(" IOCTL_EVENT_WRITE\n");
status = DokanEventWrite(DeviceObject, Irp);
break;
case IOCTL_KEEPALIVE:
DDbgPrint(" IOCTL_KEEPALIVE\n");
if (IsFlagOn(vcb->Flags, VCB_MOUNTED)) {
ExEnterCriticalRegionAndAcquireResourceExclusive(&dcb->Resource);
DokanUpdateTimeout(&dcb->TickCount, DOKAN_KEEPALIVE_TIMEOUT);
ExReleaseResourceAndLeaveCriticalRegion(&dcb->Resource);
status = STATUS_SUCCESS;
} else {
DDbgPrint(" device is not mounted\n");
status = STATUS_INSUFFICIENT_RESOURCES;
}
break;
case IOCTL_RESET_TIMEOUT:
status = DokanResetPendingIrpTimeout(DeviceObject, Irp);
break;
case IOCTL_GET_ACCESS_TOKEN:
status = DokanGetAccessToken(DeviceObject, Irp);
break;
default: {
ULONG baseCode = DEVICE_TYPE_FROM_CTL_CODE(
irpSp->Parameters.DeviceIoControl.IoControlCode);
status = STATUS_NOT_IMPLEMENTED;
// In case of IOCTL_STORAGE_BASE or IOCTL_DISK_BASE OR
// FILE_DEVICE_NETWORK_FILE_SYSTEM or MOUNTDEVCONTROLTYPE ioctl type, pass
// to DiskDeviceControl to avoid code duplication
// TODO: probably not the best way to pass down Irp...
if (baseCode == IOCTL_STORAGE_BASE || baseCode == IOCTL_DISK_BASE ||
baseCode == FILE_DEVICE_NETWORK_FILE_SYSTEM ||
baseCode == MOUNTDEVCONTROLTYPE) {
status = DiskDeviceControlWithLock(dcb->DeviceObject, Irp);
}
if (status == STATUS_NOT_IMPLEMENTED) {
PrintUnknownDeviceIoctlCode(
irpSp->Parameters.DeviceIoControl.IoControlCode);
}
} break;
} // switch IoControlCode
} __finally {
if (status != STATUS_PENDING) {
if (IsDeletePending(DeviceObject)) {
DDbgPrint(" DeviceObject is invalid, so prevent BSOD");
status = STATUS_DEVICE_REMOVED;
}
DokanCompleteIrpRequest(Irp, status, Irp->IoStatus.Information);
}
if (controlCode != IOCTL_EVENT_WAIT && controlCode != IOCTL_EVENT_INFO &&
controlCode != IOCTL_KEEPALIVE) {
DokanPrintNTStatus(status);
DDbgPrint("<== DokanDispatchIoControl\n");
}
}
return status;
}
static
VOID
TestResourceUndocumentedShortcuts(
IN PERESOURCE Res,
IN BOOLEAN AreApcsDisabled)
{
PVOID Ret;
LONG Count = 0;
ok_bool_false(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_uint(KeAreAllApcsDisabled(), AreApcsDisabled);
/* ExEnterCriticalRegionAndAcquireResourceShared, ExEnterCriticalRegionAndAcquireSharedWaitForExclusive */
Count = 0;
Ret = ExEnterCriticalRegionAndAcquireResourceShared(Res); ++Count;
ok_eq_pointer(Ret, KeGetCurrentThread()->Win32Thread);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
Ret = ExEnterCriticalRegionAndAcquireResourceShared(Res); ++Count;
ok_eq_pointer(Ret, KeGetCurrentThread()->Win32Thread);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
ExEnterCriticalRegionAndAcquireSharedWaitForExclusive(Res); ++Count;
ok_eq_pointer(Ret, KeGetCurrentThread()->Win32Thread);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
while (Count-- > 1)
{
ExReleaseResourceAndLeaveCriticalRegion(Res);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
}
ExReleaseResourceAndLeaveCriticalRegion(Res);
ok_bool_false(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
/* ExEnterCriticalRegionAndAcquireResourceExclusive */
Count = 0;
ok_bool_false(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
Ret = ExEnterCriticalRegionAndAcquireResourceExclusive(Res); ++Count;
ok_eq_pointer(Ret, KeGetCurrentThread()->Win32Thread);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, TRUE, Count, 0LU, 0LU);
Ret = ExEnterCriticalRegionAndAcquireResourceExclusive(Res); ++Count;
ok_eq_pointer(Ret, KeGetCurrentThread()->Win32Thread);
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, TRUE, Count, 0LU, 0LU);
ExReleaseResourceAndLeaveCriticalRegion(Res); --Count;
ok_bool_true(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_bool(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, TRUE, Count, 0LU, 0LU);
ExReleaseResourceAndLeaveCriticalRegion(Res); --Count;
ok_bool_false(KeAreApcsDisabled(), "KeAreApcsDisabled returned");
ok_eq_uint(KeAreAllApcsDisabled(), AreApcsDisabled);
CheckResourceStatus(Res, FALSE, Count, 0LU, 0LU);
}