diff options
Diffstat (limited to 'SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c')
| -rw-r--r-- | SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c b/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c new file mode 100644 index 0000000000..d0e6b7de06 --- /dev/null +++ b/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;
+}
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