diff options
Diffstat (limited to 'src/VBox/Devices/EFI/Firmware/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c')
-rw-r--r-- | src/VBox/Devices/EFI/Firmware/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c b/src/VBox/Devices/EFI/Firmware/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c new file mode 100644 index 00000000..800462a1 --- /dev/null +++ b/src/VBox/Devices/EFI/Firmware/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c @@ -0,0 +1,145 @@ +/** @file + RNG Driver to produce the UEFI Random Number Generator protocol. + + The driver will use the new RDRAND instruction to produce high-quality, high-performance + entropy and random number. + + RNG Algorithms defined in UEFI 2.4: + - EFI_RNG_ALGORITHM_SP800_90_CTR_256_GUID - Supported + (RDRAND implements a hardware NIST SP800-90 AES-CTR-256 based DRBG) + - EFI_RNG_ALGORITHM_RAW - Supported + (Structuring RDRAND invocation can be guaranteed as high-quality entropy source) + - EFI_RNG_ALGORITHM_SP800_90_HMAC_256_GUID - Unsupported + - EFI_RNG_ALGORITHM_SP800_90_HASH_256_GUID - Unsupported + - EFI_RNG_ALGORITHM_X9_31_3DES_GUID - Unsupported + - EFI_RNG_ALGORITHM_X9_31_AES_GUID - Unsupported + + Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.<BR> + (C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR> + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include "RdRand.h" +#include "RngDxeInternals.h" + +/** + 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 + ) +{ + EFI_STATUS Status; + + if ((RNGValueLength == 0) || (RNGValue == NULL)) { + return EFI_INVALID_PARAMETER; + } + + Status = EFI_UNSUPPORTED; + if (RNGAlgorithm == NULL) { + // + // Use the default RNG algorithm if RNGAlgorithm is NULL. + // + RNGAlgorithm = &gEfiRngAlgorithmSp80090Ctr256Guid; + } + + // + // NIST SP800-90-AES-CTR-256 supported by RDRAND + // + if (CompareGuid (RNGAlgorithm, &gEfiRngAlgorithmSp80090Ctr256Guid)) { + Status = RngGetBytes (RNGValueLength, RNGValue); + return Status; + } + + // + // The "raw" algorithm is intended to provide entropy directly + // + if (CompareGuid (RNGAlgorithm, &gEfiRngAlgorithmRaw)) { + // + // When a DRBG is used on the output of a entropy source, + // its security level must be at least 256 bits according to UEFI Spec. + // + if (RNGValueLength < 32) { + return EFI_INVALID_PARAMETER; + } + + Status = RdRandGenerateEntropy (RNGValueLength, RNGValue); + return Status; + } + + // + // Other algorithms were unsupported by this driver. + // + return Status; +} + +/** + Returns information about the random number generation implementation. + + @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_BUFFER_TOO_SMALL The buffer RNGAlgorithmList is too small to hold the result. + +**/ +UINTN +EFIAPI +ArchGetSupportedRngAlgorithms ( + IN OUT UINTN *RNGAlgorithmListSize, + OUT EFI_RNG_ALGORITHM *RNGAlgorithmList + ) +{ + UINTN RequiredSize; + EFI_RNG_ALGORITHM *CpuRngSupportedAlgorithm; + + RequiredSize = 2 * sizeof (EFI_RNG_ALGORITHM); + + if (*RNGAlgorithmListSize < RequiredSize) { + *RNGAlgorithmListSize = RequiredSize; + return EFI_BUFFER_TOO_SMALL; + } + + CpuRngSupportedAlgorithm = PcdGetPtr (PcdCpuRngSupportedAlgorithm); + + CopyMem(&RNGAlgorithmList[0], CpuRngSupportedAlgorithm, sizeof (EFI_RNG_ALGORITHM)); + + // x86 platforms also support EFI_RNG_ALGORITHM_RAW via RDSEED + CopyMem(&RNGAlgorithmList[1], &gEfiRngAlgorithmRaw, sizeof (EFI_RNG_ALGORITHM)); + + *RNGAlgorithmListSize = RequiredSize; + return EFI_SUCCESS; +} |