4b3e9d80be
RngGetBytes() relies on the RngLib. The RngLib might use the RNDR instruction if the FEAT_RNG feature is present. RngGetInfo and RngGetRNG both must check that RngGetBytes() is working before advertising/using it. To do so, allocate an array storing the available algorithms. The Rng algorithm at the lowest index will be the default Rng algorithm. The array is shared between RngGetInfo and RngGetRNG. This array is allocated when the driver is loaded, and freed when unloaded. This patch also prevents from having PcdCpuRngSupportedAlgorithm let to a zero GUID, but let the possibility to have no valid Rng algorithm in such case. Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com> Acked-by: Jiewen Yao <jiewen.yao@intel.com>
139 lines
5.2 KiB
C
139 lines
5.2 KiB
C
/** @file
|
|
Function prototypes for UEFI Random Number Generator protocol support.
|
|
|
|
Copyright (c) 2021, NUVIA Inc. All rights reserved.<BR>
|
|
|
|
SPDX-License-Identifier: BSD-2-Clause-Patent
|
|
|
|
**/
|
|
|
|
#ifndef RNGDXE_INTERNALS_H_
|
|
#define RNGDXE_INTERNALS_H_
|
|
|
|
#include <Protocol/Rng.h>
|
|
|
|
//
|
|
// Array containing the validated Rng algorithm.
|
|
// The entry with the lowest index will be the default algorithm.
|
|
//
|
|
extern UINTN mAvailableAlgoArrayCount;
|
|
extern EFI_RNG_ALGORITHM *mAvailableAlgoArray;
|
|
|
|
/** Allocate and initialize mAvailableAlgoArray with the available
|
|
Rng algorithms. Also update mAvailableAlgoArrayCount.
|
|
|
|
@retval EFI_SUCCESS The function completed successfully.
|
|
@retval EFI_OUT_OF_RESOURCES Could not allocate memory.
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
GetAvailableAlgorithms (
|
|
VOID
|
|
);
|
|
|
|
/** Free mAvailableAlgoArray.
|
|
**/
|
|
VOID
|
|
EFIAPI
|
|
FreeAvailableAlgorithms (
|
|
VOID
|
|
);
|
|
|
|
/**
|
|
Returns information about the random number generation implementation.
|
|
|
|
@param[in] This A pointer to the EFI_RNG_PROTOCOL instance.
|
|
@param[in,out] RNGAlgorithmListSize On input, the size in bytes of RNGAlgorithmList.
|
|
On output with a return code of EFI_SUCCESS, the size
|
|
in bytes of the data returned in RNGAlgorithmList. On output
|
|
with a return code of EFI_BUFFER_TOO_SMALL,
|
|
the size of RNGAlgorithmList required to obtain the list.
|
|
@param[out] RNGAlgorithmList A caller-allocated memory buffer filled by the driver
|
|
with one EFI_RNG_ALGORITHM element for each supported
|
|
RNG algorithm. The list must not change across multiple
|
|
calls to the same driver. The first algorithm in the list
|
|
is the default algorithm for the driver.
|
|
|
|
@retval EFI_SUCCESS The RNG algorithm list was returned successfully.
|
|
@retval EFI_UNSUPPORTED The services is not supported by this driver.
|
|
@retval EFI_DEVICE_ERROR The list of algorithms could not be retrieved due to a
|
|
hardware or firmware error.
|
|
@retval EFI_INVALID_PARAMETER One or more of the parameters are incorrect.
|
|
@retval EFI_BUFFER_TOO_SMALL The buffer RNGAlgorithmList is too small to hold the result.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
RngGetInfo (
|
|
IN EFI_RNG_PROTOCOL *This,
|
|
IN OUT UINTN *RNGAlgorithmListSize,
|
|
OUT EFI_RNG_ALGORITHM *RNGAlgorithmList
|
|
);
|
|
|
|
/**
|
|
Produces and returns an RNG value using either the default or specified RNG algorithm.
|
|
|
|
@param[in] This A pointer to the EFI_RNG_PROTOCOL instance.
|
|
@param[in] RNGAlgorithm A pointer to the EFI_RNG_ALGORITHM that identifies the RNG
|
|
algorithm to use. May be NULL in which case the function will
|
|
use its default RNG algorithm.
|
|
@param[in] RNGValueLength The length in bytes of the memory buffer pointed to by
|
|
RNGValue. The driver shall return exactly this numbers of bytes.
|
|
@param[out] RNGValue A caller-allocated memory buffer filled by the driver with the
|
|
resulting RNG value.
|
|
|
|
@retval EFI_SUCCESS The RNG value was returned successfully.
|
|
@retval EFI_UNSUPPORTED The algorithm specified by RNGAlgorithm is not supported by
|
|
this driver.
|
|
@retval EFI_DEVICE_ERROR An RNG value could not be retrieved due to a hardware or
|
|
firmware error.
|
|
@retval EFI_NOT_READY There is not enough random data available to satisfy the length
|
|
requested by RNGValueLength.
|
|
@retval EFI_INVALID_PARAMETER RNGValue is NULL or RNGValueLength is zero.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
RngGetRNG (
|
|
IN EFI_RNG_PROTOCOL *This,
|
|
IN EFI_RNG_ALGORITHM *RNGAlgorithm OPTIONAL,
|
|
IN UINTN RNGValueLength,
|
|
OUT UINT8 *RNGValue
|
|
);
|
|
|
|
/**
|
|
Runs CPU RNG instruction to fill a buffer of arbitrary size with random bytes.
|
|
|
|
@param[in] Length Size of the buffer, in bytes, to fill with.
|
|
@param[out] RandBuffer Pointer to the buffer to store the random result.
|
|
|
|
@retval EFI_SUCCESS Random bytes generation succeeded.
|
|
@retval EFI_NOT_READY Failed to request random bytes.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
RngGetBytes (
|
|
IN UINTN Length,
|
|
OUT UINT8 *RandBuffer
|
|
);
|
|
|
|
/**
|
|
Generate high-quality entropy source using a TRNG or through RDRAND.
|
|
|
|
@param[in] Length Size of the buffer, in bytes, to fill with.
|
|
@param[out] Entropy Pointer to the buffer to store the entropy data.
|
|
|
|
@retval EFI_SUCCESS Entropy generation succeeded.
|
|
@retval EFI_NOT_READY Failed to request random data.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
GenerateEntropy (
|
|
IN UINTN Length,
|
|
OUT UINT8 *Entropy
|
|
);
|
|
|
|
#endif // RNGDXE_INTERNALS_H_
|