winfsp/src/dll/fsctl.c
2020-10-06 16:37:33 -07:00

592 lines
18 KiB
C

/**
* @file dll/fsctl.c
*
* @copyright 2015-2020 Bill Zissimopoulos
*/
/*
* This file is part of WinFsp.
*
* You can redistribute it and/or modify it under the terms of the GNU
* General Public License version 3 as published by the Free Software
* Foundation.
*
* Licensees holding a valid commercial license may use this software
* in accordance with the commercial license agreement provided in
* conjunction with the software. The terms and conditions of any such
* commercial license agreement shall govern, supersede, and render
* ineffective any application of the GPLv3 license to this software,
* notwithstanding of any reference thereto in the software or
* associated repository.
*/
#include <dll/library.h>
#include <aclapi.h>
#define GLOBALROOT L"\\\\?\\GLOBALROOT"
#define PREFIXW L"" FSP_FSCTL_VOLUME_PARAMS_PREFIX
#define PREFIXW_SIZE (sizeof PREFIXW - sizeof(WCHAR))
static NTSTATUS FspFsctlStartService(VOID);
FSP_API NTSTATUS FspFsctlCreateVolume(PWSTR DevicePath,
const FSP_FSCTL_VOLUME_PARAMS *VolumeParams,
PWCHAR VolumeNameBuf, SIZE_T VolumeNameSize,
PHANDLE PVolumeHandle)
{
NTSTATUS Result;
PWSTR DeviceRoot;
SIZE_T DeviceRootSize, DevicePathSize, VolumeParamsSize;
WCHAR DevicePathBuf[MAX_PATH + sizeof *VolumeParams], *DevicePathPtr, *DevicePathEnd;
HANDLE VolumeHandle = INVALID_HANDLE_VALUE;
DWORD Bytes;
if (sizeof(WCHAR) <= VolumeNameSize)
VolumeNameBuf[0] = L'\0';
*PVolumeHandle = INVALID_HANDLE_VALUE;
/* check lengths; everything (including encoded volume params) must fit within DevicePathBuf */
DeviceRoot = L'\\' == DevicePath[0] ? GLOBALROOT : GLOBALROOT "\\Device\\";
DeviceRootSize = lstrlenW(DeviceRoot) * sizeof(WCHAR);
DevicePathSize = lstrlenW(DevicePath) * sizeof(WCHAR);
if (DeviceRootSize + DevicePathSize + PREFIXW_SIZE +
sizeof *VolumeParams * sizeof(WCHAR) + sizeof(WCHAR) > sizeof DevicePathBuf)
return STATUS_INVALID_PARAMETER;
/* prepare the device path to be opened; encode the volume params in the Unicode private area */
DevicePathPtr = DevicePathBuf;
memcpy(DevicePathPtr, DeviceRoot, DeviceRootSize);
DevicePathPtr = (PVOID)((PUINT8)DevicePathPtr + DeviceRootSize);
memcpy(DevicePathPtr, DevicePath, DevicePathSize);
DevicePathPtr = (PVOID)((PUINT8)DevicePathPtr + DevicePathSize);
memcpy(DevicePathPtr, PREFIXW, PREFIXW_SIZE);
VolumeParamsSize = 0 == VolumeParams->Version ?
sizeof(FSP_FSCTL_VOLUME_PARAMS_V0) :
VolumeParams->Version;
DevicePathPtr = (PVOID)((PUINT8)DevicePathPtr + PREFIXW_SIZE);
DevicePathEnd = (PVOID)((PUINT8)DevicePathPtr + VolumeParamsSize * sizeof(WCHAR));
for (PUINT8 VolumeParamsPtr = (PVOID)VolumeParams;
DevicePathEnd > DevicePathPtr; DevicePathPtr++, VolumeParamsPtr++)
{
WCHAR Value = 0xF000 | *VolumeParamsPtr;
*DevicePathPtr = Value;
}
*DevicePathPtr = L'\0';
Result = FspFsctlStartService();
if (!NT_SUCCESS(Result))
return Result;
VolumeHandle = CreateFileW(DevicePathBuf,
0, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, 0);
if (INVALID_HANDLE_VALUE == VolumeHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
if (STATUS_OBJECT_PATH_NOT_FOUND == Result ||
STATUS_OBJECT_NAME_NOT_FOUND == Result)
Result = STATUS_NO_SUCH_DEVICE;
goto exit;
}
if (!DeviceIoControl(VolumeHandle, FSP_FSCTL_VOLUME_NAME,
0, 0,
VolumeNameBuf, (DWORD)VolumeNameSize,
&Bytes, 0))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
Result = STATUS_SUCCESS;
exit:
if (NT_SUCCESS(Result))
*PVolumeHandle = VolumeHandle;
else
CloseHandle(VolumeHandle);
return Result;
}
FSP_API NTSTATUS FspFsctlMakeMountdev(HANDLE VolumeHandle,
BOOLEAN Persistent, GUID *UniqueId)
{
DWORD Bytes;
if (!DeviceIoControl(VolumeHandle,
FSP_FSCTL_MOUNTDEV,
&Persistent, sizeof Persistent, UniqueId, sizeof *UniqueId,
&Bytes, 0))
return FspNtStatusFromWin32(GetLastError());
return STATUS_SUCCESS;
}
FSP_API NTSTATUS FspFsctlTransact(HANDLE VolumeHandle,
PVOID ResponseBuf, SIZE_T ResponseBufSize,
PVOID RequestBuf, SIZE_T *PRequestBufSize,
BOOLEAN Batch)
{
NTSTATUS Result = STATUS_SUCCESS;
DWORD Bytes = 0;
if (0 != PRequestBufSize)
{
Bytes = (DWORD)*PRequestBufSize;
*PRequestBufSize = 0;
}
if (!DeviceIoControl(VolumeHandle,
Batch ? FSP_FSCTL_TRANSACT_BATCH : FSP_FSCTL_TRANSACT,
ResponseBuf, (DWORD)ResponseBufSize, RequestBuf, Bytes,
&Bytes, 0))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
if (0 != PRequestBufSize)
*PRequestBufSize = Bytes;
exit:
return Result;
}
FSP_API NTSTATUS FspFsctlStop(HANDLE VolumeHandle)
{
DWORD Bytes;
if (!DeviceIoControl(VolumeHandle, FSP_FSCTL_STOP, 0, 0, 0, 0, &Bytes, 0))
return FspNtStatusFromWin32(GetLastError());
return STATUS_SUCCESS;
}
FSP_API NTSTATUS FspFsctlNotify(HANDLE VolumeHandle,
FSP_FSCTL_NOTIFY_INFO *NotifyInfo, SIZE_T Size)
{
NTSTATUS Result = STATUS_SUCCESS;
DWORD Bytes = 0;
if (!DeviceIoControl(VolumeHandle,
FSP_FSCTL_NOTIFY,
NotifyInfo, (DWORD)Size, 0, 0,
&Bytes, 0))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
exit:
return Result;
}
FSP_API NTSTATUS FspFsctlGetVolumeList(PWSTR DevicePath,
PWCHAR VolumeListBuf, PSIZE_T PVolumeListSize)
{
NTSTATUS Result;
PWSTR DeviceRoot;
SIZE_T DeviceRootSize, DevicePathSize;
WCHAR DevicePathBuf[MAX_PATH], *DevicePathPtr;
HANDLE VolumeHandle = INVALID_HANDLE_VALUE;
DWORD Bytes;
/* check lengths; everything must fit within MAX_PATH */
DeviceRoot = L'\\' == DevicePath[0] ? GLOBALROOT : GLOBALROOT "\\Device\\";
DeviceRootSize = lstrlenW(DeviceRoot) * sizeof(WCHAR);
DevicePathSize = lstrlenW(DevicePath) * sizeof(WCHAR);
if (DeviceRootSize + DevicePathSize + sizeof(WCHAR) > sizeof DevicePathBuf)
return STATUS_INVALID_PARAMETER;
/* prepare the device path to be opened */
DevicePathPtr = DevicePathBuf;
memcpy(DevicePathPtr, DeviceRoot, DeviceRootSize);
DevicePathPtr = (PVOID)((PUINT8)DevicePathPtr + DeviceRootSize);
memcpy(DevicePathPtr, DevicePath, DevicePathSize);
DevicePathPtr = (PVOID)((PUINT8)DevicePathPtr + DevicePathSize);
*DevicePathPtr = L'\0';
VolumeHandle = CreateFileW(DevicePathBuf,
0, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, 0);
if (INVALID_HANDLE_VALUE == VolumeHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
if (STATUS_OBJECT_PATH_NOT_FOUND == Result ||
STATUS_OBJECT_NAME_NOT_FOUND == Result)
Result = STATUS_NO_SUCH_DEVICE;
goto exit;
}
if (!DeviceIoControl(VolumeHandle, FSP_FSCTL_VOLUME_LIST,
0, 0,
VolumeListBuf, (DWORD)*PVolumeListSize,
&Bytes, 0))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
*PVolumeListSize = Bytes;
Result = STATUS_SUCCESS;
exit:
if (INVALID_HANDLE_VALUE != VolumeHandle)
CloseHandle(VolumeHandle);
return Result;
}
FSP_API NTSTATUS FspFsctlPreflight(PWSTR DevicePath)
{
NTSTATUS Result;
SIZE_T VolumeListSize;
Result = FspFsctlStartService();
if (!NT_SUCCESS(Result))
return Result;
VolumeListSize = 0;
Result = FspFsctlGetVolumeList(DevicePath, 0, &VolumeListSize);
if (!NT_SUCCESS(Result) && STATUS_BUFFER_TOO_SMALL != Result)
return Result;
return STATUS_SUCCESS;
}
static NTSTATUS FspFsctlStartService(VOID)
{
PWSTR DriverName = L"" FSP_FSCTL_DRIVER_NAME;
SC_HANDLE ScmHandle = 0;
SC_HANDLE SvcHandle = 0;
SERVICE_STATUS ServiceStatus;
DWORD LastError;
NTSTATUS Result;
/* Determine if we are running inside container.
*
* See https://github.com/microsoft/perfview/blob/V1.9.65/src/TraceEvent/TraceEventSession.cs#L525
* See https://stackoverflow.com/a/50748300
*/
LastError = RegGetValueW(
HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control",
L"ContainerType",
RRF_RT_REG_DWORD, 0,
0, 0);
if (ERROR_SUCCESS == LastError)
{
Result = STATUS_SUCCESS;
goto exit;
}
ScmHandle = OpenSCManagerW(0, 0, 0);
if (0 == ScmHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
SvcHandle = OpenServiceW(ScmHandle, DriverName, SERVICE_QUERY_STATUS | SERVICE_START);
if (0 == SvcHandle)
{
LastError = GetLastError();
if (ERROR_SERVICE_DOES_NOT_EXIST != LastError)
Result = FspNtStatusFromWin32(LastError);
else
Result = STATUS_NO_SUCH_DEVICE;
goto exit;
}
if (!StartServiceW(SvcHandle, 0, 0))
{
LastError = GetLastError();
if (ERROR_SERVICE_ALREADY_RUNNING != LastError)
Result = FspNtStatusFromWin32(LastError);
else
Result = STATUS_SUCCESS;
goto exit;
}
/* Poll until the service is running! Yes, that's the best we can do! */
Result = STATUS_DRIVER_UNABLE_TO_LOAD;
for (DWORD Timeout = 500, N = 20, I = 0; N > I; I++)
/* wait up to 500ms * 20 = 10000ms = 10s */
{
if (!QueryServiceStatus(SvcHandle, &ServiceStatus))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
if (SERVICE_RUNNING == ServiceStatus.dwCurrentState)
{
Result = STATUS_SUCCESS;
break;
}
Sleep(Timeout);
}
exit:
if (0 != SvcHandle)
CloseServiceHandle(SvcHandle);
if (0 != ScmHandle)
CloseServiceHandle(ScmHandle);
return Result;
}
static NTSTATUS FspFsctlFixServiceSecurity(HANDLE SvcHandle)
{
/*
* This function adds an ACE that allows Everyone to start a service.
*/
PSID WorldSid;
PSECURITY_DESCRIPTOR SecurityDescriptor = 0;
PSECURITY_DESCRIPTOR NewSecurityDescriptor = 0;
EXPLICIT_ACCESSW AccessEntry;
ACCESS_MASK AccessRights;
PACL Dacl;
BOOL DaclPresent, DaclDefaulted;
DWORD Size;
DWORD LastError;
NTSTATUS Result;
/* get the Everyone (World) SID */
WorldSid = FspWksidGet(WinWorldSid);
if (0 == WorldSid)
{
Result = STATUS_INSUFFICIENT_RESOURCES;
goto exit;
}
/* get the service security descriptor DACL */
Size = 0;
if (!QueryServiceObjectSecurity(SvcHandle, DACL_SECURITY_INFORMATION, SecurityDescriptor, Size, &Size))
{
LastError = GetLastError();
if (ERROR_INSUFFICIENT_BUFFER != LastError)
{
Result = FspNtStatusFromWin32(LastError);
goto exit;
}
}
SecurityDescriptor = MemAlloc(Size);
if (0 == SecurityDescriptor)
{
Result = STATUS_INSUFFICIENT_RESOURCES;
goto exit;
}
if (!QueryServiceObjectSecurity(SvcHandle, DACL_SECURITY_INFORMATION, SecurityDescriptor, Size, &Size))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
/* extract the DACL */
if (!GetSecurityDescriptorDacl(SecurityDescriptor, &DaclPresent, &Dacl, &DaclDefaulted))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
/* prepare an EXPLICIT_ACCESS for the SERVICE_QUERY_STATUS | SERVICE_START right for Everyone */
AccessEntry.grfAccessPermissions = SERVICE_QUERY_STATUS | SERVICE_START;
AccessEntry.grfAccessMode = GRANT_ACCESS;
AccessEntry.grfInheritance = NO_INHERITANCE;
AccessEntry.Trustee.pMultipleTrustee = 0;
AccessEntry.Trustee.MultipleTrusteeOperation = NO_MULTIPLE_TRUSTEE;
AccessEntry.Trustee.TrusteeForm = TRUSTEE_IS_SID;
AccessEntry.Trustee.TrusteeType = TRUSTEE_IS_UNKNOWN;
AccessEntry.Trustee.ptstrName = WorldSid;
/* get the effective rights for Everyone */
AccessRights = 0;
if (DaclPresent && 0 != Dacl)
{
LastError = GetEffectiveRightsFromAclW(Dacl, &AccessEntry.Trustee, &AccessRights);
if (0 != LastError)
/*
* Apparently GetEffectiveRightsFromAclW can fail with ERROR_CIRCULAR_DEPENDENCY
* in some rare circumstances. Calling GetEffectiveRightsFromAclW is not essential
* in this instance. It is only done to check whether the "Everyone/World" SID
* already has the access required to start the FSD; if it does not have those
* rights already they are added. It is probably safe to just assume that the
* required rights are not there if GetEffectiveRightsFromAclW fails; the worst
* that can happen is that the rights get added twice (which is benign).
*
* See https://github.com/billziss-gh/winfsp/issues/62
*/
AccessRights = 0;
}
/* do we have the required access rights? */
if (AccessEntry.grfAccessPermissions != (AccessRights & AccessEntry.grfAccessPermissions))
{
/* create a new security descriptor with the new access */
LastError = BuildSecurityDescriptorW(0, 0, 1, &AccessEntry, 0, 0, SecurityDescriptor,
&Size, &NewSecurityDescriptor);
if (0 != LastError)
{
Result = FspNtStatusFromWin32(LastError);
goto exit;
}
/* set the new service security descriptor DACL */
if (!SetServiceObjectSecurity(SvcHandle, DACL_SECURITY_INFORMATION, NewSecurityDescriptor))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
}
Result = STATUS_SUCCESS;
exit:
LocalFree(NewSecurityDescriptor);
MemFree(SecurityDescriptor);
return Result;
}
NTSTATUS FspFsctlRegister(VOID)
{
extern HINSTANCE DllInstance;
PWSTR DriverName = L"" FSP_FSCTL_DRIVER_NAME;
WCHAR DriverPath[MAX_PATH];
DWORD Size;
SC_HANDLE ScmHandle = 0;
SC_HANDLE SvcHandle = 0;
PVOID VersionInfo = 0;
SERVICE_DESCRIPTION ServiceDescription;
NTSTATUS Result;
if (0 == GetModuleFileNameW(DllInstance, DriverPath, MAX_PATH))
return FspNtStatusFromWin32(GetLastError());
Size = lstrlenW(DriverPath);
if (4 < Size &&
(L'.' == DriverPath[Size - 4]) &&
(L'D' == DriverPath[Size - 3] || L'd' == DriverPath[Size - 3]) &&
(L'L' == DriverPath[Size - 2] || L'l' == DriverPath[Size - 2]) &&
(L'L' == DriverPath[Size - 1] || L'l' == DriverPath[Size - 1]) &&
(L'\0' == DriverPath[Size]))
{
DriverPath[Size - 3] = L's';
DriverPath[Size - 2] = L'y';
DriverPath[Size - 1] = L's';
}
else
/* should not happen! */
return STATUS_NO_SUCH_DEVICE;
ScmHandle = OpenSCManagerW(0, 0, SC_MANAGER_CREATE_SERVICE);
if (0 == ScmHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
SvcHandle = OpenServiceW(ScmHandle, DriverName, SERVICE_CHANGE_CONFIG | READ_CONTROL | WRITE_DAC);
if (0 != SvcHandle)
{
if (!ChangeServiceConfigW(SvcHandle,
SERVICE_FILE_SYSTEM_DRIVER, SERVICE_DEMAND_START, SERVICE_ERROR_NORMAL, DriverPath,
0, 0, 0, 0, 0, DriverName))
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
}
else
{
SvcHandle = CreateServiceW(ScmHandle, DriverName, DriverName,
SERVICE_CHANGE_CONFIG | READ_CONTROL | WRITE_DAC,
SERVICE_FILE_SYSTEM_DRIVER, SERVICE_DEMAND_START, SERVICE_ERROR_NORMAL, DriverPath,
0, 0, 0, 0, 0);
if (0 == SvcHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
}
Size = GetFileVersionInfoSizeW(DriverPath, &Size/*dummy*/);
if (0 < Size)
{
VersionInfo = MemAlloc(Size);
if (0 != VersionInfo &&
GetFileVersionInfoW(DriverPath, 0, Size, VersionInfo) &&
VerQueryValueW(VersionInfo, L"\\StringFileInfo\\040904b0\\FileDescription",
&ServiceDescription.lpDescription, &Size))
{
ChangeServiceConfig2W(SvcHandle, SERVICE_CONFIG_DESCRIPTION, &ServiceDescription);
}
}
Result = FspFsctlFixServiceSecurity(SvcHandle);
if (!NT_SUCCESS(Result))
goto exit;
Result = STATUS_SUCCESS;
exit:
MemFree(VersionInfo);
if (0 != SvcHandle)
CloseServiceHandle(SvcHandle);
if (0 != ScmHandle)
CloseServiceHandle(ScmHandle);
return Result;
}
NTSTATUS FspFsctlUnregister(VOID)
{
PWSTR DriverName = L"" FSP_FSCTL_DRIVER_NAME;
SC_HANDLE ScmHandle = 0;
SC_HANDLE SvcHandle = 0;
DWORD LastError;
NTSTATUS Result;
ScmHandle = OpenSCManagerW(0, 0, SC_MANAGER_CREATE_SERVICE);
/*
* The SC_MANAGER_CREATE_SERVICE access right is not strictly needed here,
* but we use it to enforce admin rights.
*/
if (0 == ScmHandle)
{
Result = FspNtStatusFromWin32(GetLastError());
goto exit;
}
SvcHandle = OpenServiceW(ScmHandle, DriverName, DELETE);
if (0 == SvcHandle)
{
LastError = GetLastError();
if (ERROR_SERVICE_DOES_NOT_EXIST != LastError)
Result = FspNtStatusFromWin32(LastError);
else
Result = STATUS_SUCCESS;
goto exit;
}
if (!DeleteService(SvcHandle))
{
LastError = GetLastError();
if (ERROR_SERVICE_MARKED_FOR_DELETE != LastError)
Result = FspNtStatusFromWin32(LastError);
else
Result = STATUS_SUCCESS;
goto exit;
}
Result = STATUS_SUCCESS;
exit:
if (0 != SvcHandle)
CloseServiceHandle(SvcHandle);
if (0 != ScmHandle)
CloseServiceHandle(ScmHandle);
return Result;
}