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| author | Mounir IDRASSI <mounir.idrassi@idrix.fr> | 2017-07-04 02:05:11 +0200 |
|---|---|---|
| committer | Mounir IDRASSI <mounir.idrassi@idrix.fr> | 2017-07-04 02:26:24 +0200 |
| commit | 89efcdb8cd95ea798187fe4062a73fa5d2fca456 (patch) | |
| tree | 5b87e340ffc7fb6ad8a8859750aa388487188f8f /src/Driver/Ntdriver.c | |
| parent | c2f6190627de27903264258c6ea8ee72199c0c81 (diff) | |
| download | VeraCrypt-89efcdb8cd95ea798187fe4062a73fa5d2fca456.tar.gz VeraCrypt-89efcdb8cd95ea798187fe4062a73fa5d2fca456.zip | |
Windows Driver: correctly save and restore extended processor state when performing AVX operations on Windows 7 and later. Enhance readability of code handling save/restore of floating point state.
Diffstat (limited to 'src/Driver/Ntdriver.c')
| -rw-r--r-- | src/Driver/Ntdriver.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/src/Driver/Ntdriver.c b/src/Driver/Ntdriver.c index ab555904..8f6f151f 100644 --- a/src/Driver/Ntdriver.c +++ b/src/Driver/Ntdriver.c @@ -73,6 +73,11 @@ #pragma alloc_text(INIT,DriverEntry) #pragma alloc_text(INIT,TCCreateRootDeviceObject) +/* We need to silence 'type cast' warning in order to use MmGetSystemRoutineAddress. + * MmGetSystemRoutineAddress() should have been declare FARPROC instead of PVOID. + */ +#pragma warning(disable:4055) + PDRIVER_OBJECT TCDriverObject; PDEVICE_OBJECT RootDeviceObject = NULL; static KMUTEX RootDeviceControlMutex; @@ -91,6 +96,8 @@ static size_t EncryptionThreadPoolFreeCpuCountLimit = 0; static BOOL SystemFavoriteVolumeDirty = FALSE; static BOOL PagingFileCreationPrevented = FALSE; static BOOL EnableExtendedIoctlSupport = FALSE; +static KeSaveExtendedProcessorStateFn KeSaveExtendedProcessorStatePtr = NULL; +static KeRestoreExtendedProcessorStateFn KeRestoreExtendedProcessorStatePtr = NULL; POOL_TYPE ExDefaultNonPagedPoolType = NonPagedPool; ULONG ExDefaultMdlProtection = 0; @@ -119,6 +126,15 @@ NTSTATUS DriverEntry (PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath) ExDefaultMdlProtection = MdlMappingNoExecute; } + // KeSaveExtendedProcessorState/KeRestoreExtendedProcessorState are available starting from Windows 7 + if ((OsMajorVersion > 6) || (OsMajorVersion == 6 && OsMinorVersion >= 1)) + { + UNICODE_STRING funcName; + RtlInitUnicodeString(&funcName, L"KeSaveExtendedProcessorState"); + KeSaveExtendedProcessorStatePtr = (KeSaveExtendedProcessorStateFn) MmGetSystemRoutineAddress(&funcName); + KeRestoreExtendedProcessorStatePtr = (KeRestoreExtendedProcessorStateFn) MmGetSystemRoutineAddress(&funcName); + } + // Load dump filter if the main driver is already loaded if (NT_SUCCESS (TCDeviceIoControl (NT_ROOT_PREFIX, TC_IOCTL_GET_DRIVER_VERSION, NULL, 0, &version, sizeof (version)))) return DumpFilterEntry ((PFILTER_EXTENSION) DriverObject, (PFILTER_INITIALIZATION_DATA) RegistryPath); @@ -3960,3 +3976,28 @@ BOOL IsOSAtLeast (OSVersionEnum reqMinOS) return ((OsMajorVersion << 16 | OsMinorVersion << 8) >= (major << 16 | minor << 8)); } + +NTSTATUS NTAPI KeSaveExtendedProcessorState ( + __in ULONG64 Mask, + PXSTATE_SAVE XStateSave + ) +{ + if (KeSaveExtendedProcessorStatePtr) + { + return (KeSaveExtendedProcessorStatePtr) (Mask, XStateSave); + } + else + { + return STATUS_SUCCESS; + } +} + +VOID NTAPI KeRestoreExtendedProcessorState ( + PXSTATE_SAVE XStateSave + ) +{ + if (KeRestoreExtendedProcessorStatePtr) + { + (KeRestoreExtendedProcessorStatePtr) (XStateSave); + } +}
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