diff options
Diffstat (limited to 'src/VBox/Devices/EFI/Firmware/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c')
-rw-r--r-- | src/VBox/Devices/EFI/Firmware/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c b/src/VBox/Devices/EFI/Firmware/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c new file mode 100644 index 00000000..cf87f2df --- /dev/null +++ b/src/VBox/Devices/EFI/Firmware/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c @@ -0,0 +1,76 @@ +/** @file + + Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR> + + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include <Uefi.h> + +#include <Library/BaseLib.h> +#include <Library/DebugLib.h> +#include <Library/UefiBootServicesTableLib.h> +#include <Library/UefiRuntimeServicesTableLib.h> + +#include <Protocol/MonotonicCounter.h> + +UINT64 gCurrentMonotonicCount = 0; + +EFI_STATUS +EFIAPI +GetNextMonotonicCount ( + OUT UINT64 *Count + ) +{ + if (Count == NULL) { + return EFI_INVALID_PARAMETER; + } + + *Count = gCurrentMonotonicCount++; + return EFI_SUCCESS; +} + +EFI_STATUS +EFIAPI +GetNextHighMonotonicCount ( + OUT UINT32 *HighCount + ) +{ + if (HighCount == NULL) { + return EFI_INVALID_PARAMETER; + } + + gCurrentMonotonicCount += 0x0000000100000000ULL; + + *HighCount = (UINT32)RShiftU64 (gCurrentMonotonicCount, 32) & 0xFFFFFFFF; + + return EFI_SUCCESS; +} + + +EFI_STATUS +EFIAPI +MonotonicCounterDriverInitialize ( + IN EFI_HANDLE ImageHandle, + IN EFI_SYSTEM_TABLE *SystemTable + ) +{ + EFI_STATUS Status; + EFI_HANDLE Handle = NULL; + + // Make sure the Monotonic Counter Architectural Protocol is not already installed in the system + ASSERT_PROTOCOL_ALREADY_INSTALLED(NULL, &gEfiMonotonicCounterArchProtocolGuid); + + // Fill in the EFI Boot Services and EFI Runtime Services Monotonic Counter Fields + gBS->GetNextMonotonicCount = GetNextMonotonicCount; + gRT->GetNextHighMonotonicCount = GetNextHighMonotonicCount; + + // Install the Monotonic Counter Architectural Protocol onto a new handle + Status = gBS->InstallMultipleProtocolInterfaces ( + &Handle, + &gEfiMonotonicCounterArchProtocolGuid, NULL, + NULL + ); + return Status; +} |