diff options
Diffstat (limited to 'SecurityPkg/RandomNumberGenerator/RngDxe/RdRand.c')
| -rw-r--r-- | SecurityPkg/RandomNumberGenerator/RngDxe/RdRand.c | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/SecurityPkg/RandomNumberGenerator/RngDxe/RdRand.c b/SecurityPkg/RandomNumberGenerator/RngDxe/RdRand.c new file mode 100644 index 0000000000..7e618dc91f --- /dev/null +++ b/SecurityPkg/RandomNumberGenerator/RngDxe/RdRand.c @@ -0,0 +1,395 @@ +/** @file
+ Support routines for RDRAND instruction access.
+
+Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution. The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "RdRand.h"
+#include "AesCore.h"
+
+//
+// Bit mask used to determine if RdRand instruction is supported.
+//
+#define RDRAND_MASK 0x40000000
+
+/**
+ Determines whether or not RDRAND instruction is supported by the host hardware.
+
+ @retval EFI_SUCCESS RDRAND instruction supported.
+ @retval EFI_UNSUPPORTED RDRAND instruction not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+IsRdRandSupported (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ UINT32 RegEax;
+ UINT32 RegEbx;
+ UINT32 RegEcx;
+ UINT32 RegEdx;
+ BOOLEAN IsIntelCpu;
+
+ Status = EFI_UNSUPPORTED;
+ IsIntelCpu = FALSE;
+
+ //
+ // Checks whether the current processor is an Intel product by CPUID.
+ //
+ AsmCpuid (0, &RegEax, &RegEbx, &RegEcx, &RegEdx);
+ if ((CompareMem ((CHAR8 *)(&RegEbx), "Genu", 4) == 0) &&
+ (CompareMem ((CHAR8 *)(&RegEdx), "ineI", 4) == 0) &&
+ (CompareMem ((CHAR8 *)(&RegEcx), "ntel", 4) == 0)) {
+ IsIntelCpu = TRUE;
+ }
+
+ if (IsIntelCpu) {
+ //
+ // Determine RDRAND support by examining bit 30 of the ECX register returned by CPUID.
+ // A value of 1 indicates that processor supports RDRAND instruction.
+ //
+ AsmCpuid (1, 0, 0, &RegEcx, 0);
+
+ if ((RegEcx & RDRAND_MASK) == RDRAND_MASK) {
+ Status = EFI_SUCCESS;
+ }
+ }
+
+ return Status;
+}
+
+/**
+ Calls RDRAND to obtain a 16-bit random number.
+
+ @param[out] Rand Buffer pointer to store the random result.
+ @param[in] NeedRetry Determine whether or not to loop retry.
+
+ @retval EFI_SUCCESS RDRAND call was successful.
+ @retval EFI_NOT_READY Failed attempts to call RDRAND.
+
+**/
+EFI_STATUS
+EFIAPI
+RdRand16 (
+ OUT UINT16 *Rand,
+ IN BOOLEAN NeedRetry
+ )
+{
+ UINT32 Index;
+ UINT32 RetryCount;
+
+ if (NeedRetry) {
+ RetryCount = RETRY_LIMIT;
+ } else {
+ RetryCount = 1;
+ }
+
+ //
+ // Perform a single call to RDRAND, or enter a loop call until RDRAND succeeds.
+ //
+ for (Index = 0; Index < RetryCount; Index++) {
+ if (RdRand16Step (Rand)) {
+ return EFI_SUCCESS;
+ }
+ }
+
+ return EFI_NOT_READY;
+}
+
+/**
+ Calls RDRAND to obtain a 32-bit random number.
+
+ @param[out] Rand Buffer pointer to store the random result.
+ @param[in] NeedRetry Determine whether or not to loop retry.
+
+ @retval EFI_SUCCESS RDRAND call was successful.
+ @retval EFI_NOT_READY Failed attempts to call RDRAND.
+
+**/
+EFI_STATUS
+EFIAPI
+RdRand32 (
+ OUT UINT32 *Rand,
+ IN BOOLEAN NeedRetry
+ )
+{
+ UINT32 Index;
+ UINT32 RetryCount;
+
+ if (NeedRetry) {
+ RetryCount = RETRY_LIMIT;
+ } else {
+ RetryCount = 1;
+ }
+
+ //
+ // Perform a single call to RDRAND, or enter a loop call until RDRAND succeeds.
+ //
+ for (Index = 0; Index < RetryCount; Index++) {
+ if (RdRand32Step (Rand)) {
+ return EFI_SUCCESS;
+ }
+ }
+
+ return EFI_NOT_READY;
+}
+
+/**
+ Calls RDRAND to obtain a 64-bit random number.
+
+ @param[out] Rand Buffer pointer to store the random result.
+ @param[in] NeedRetry Determine whether or not to loop retry.
+
+ @retval EFI_SUCCESS RDRAND call was successful.
+ @retval EFI_NOT_READY Failed attempts to call RDRAND.
+
+**/
+EFI_STATUS
+EFIAPI
+RdRand64 (
+ OUT UINT64 *Rand,
+ IN BOOLEAN NeedRetry
+ )
+{
+ UINT32 Index;
+ UINT32 RetryCount;
+
+ if (NeedRetry) {
+ RetryCount = RETRY_LIMIT;
+ } else {
+ RetryCount = 1;
+ }
+
+ //
+ // Perform a single call to RDRAND, or enter a loop call until RDRAND succeeds.
+ //
+ for (Index = 0; Index < RetryCount; Index++) {
+ if (RdRand64Step (Rand)) {
+ return EFI_SUCCESS;
+ }
+ }
+
+ return EFI_NOT_READY;
+}
+
+/**
+ Calls RDRAND 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
+RdRandGetBytes (
+ IN UINTN Length,
+ OUT UINT8 *RandBuffer
+ )
+{
+ EFI_STATUS Status;
+ UINT8 *Start;
+ UINT8 *ResidualStart;
+ UINTN *BlockStart;
+ UINTN TempRand;
+ UINTN Count;
+ UINTN Residual;
+ UINTN StartLen;
+ UINTN BlockNum;
+ UINTN Index;
+
+ ResidualStart = NULL;
+ TempRand = 0;
+
+ //
+ // Compute the address of the first word aligned (32/64-bit) block in the
+ // destination buffer, depending on whether we are in 32- or 64-bit mode.
+ //
+ Start = RandBuffer;
+ if (((UINT32)(UINTN)Start % (UINT32)sizeof(UINTN)) == 0) {
+ BlockStart = (UINTN *)Start;
+ Count = Length;
+ StartLen = 0;
+ } else {
+ BlockStart = (UINTN *)(((UINTN)Start & ~(UINTN)(sizeof(UINTN) - 1)) + (UINTN)sizeof(UINTN));
+ Count = Length - (sizeof (UINTN) - (UINT32)((UINTN)Start % sizeof (UINTN)));
+ StartLen = (UINT32)((UINTN)BlockStart - (UINTN)Start);
+ }
+
+ //
+ // Compute the number of word blocks and the remaining number of bytes.
+ //
+ Residual = Count % sizeof (UINTN);
+ BlockNum = Count / sizeof (UINTN);
+ if (Residual != 0) {
+ ResidualStart = (UINT8 *) (BlockStart + BlockNum);
+ }
+
+ //
+ // Obtain a temporary random number for use in the residuals. Failout if retry fails.
+ //
+ if (StartLen > 0) {
+ Status = RdRandWord ((UINTN *) &TempRand, TRUE);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ }
+
+ //
+ // Populate the starting mis-aligned block.
+ //
+ for (Index = 0; Index < StartLen; Index++) {
+ Start[Index] = (UINT8)(TempRand & 0xff);
+ TempRand = TempRand >> 8;
+ }
+
+ //
+ // Populate the central aligned block. Fail out if retry fails.
+ //
+ Status = RdRandGetWords (BlockNum, (UINTN *)(BlockStart));
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ //
+ // Populate the final mis-aligned block.
+ //
+ if (Residual > 0) {
+ Status = RdRandWord ((UINTN *)&TempRand, TRUE);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ for (Index = 0; Index < Residual; Index++) {
+ ResidualStart[Index] = (UINT8)(TempRand & 0xff);
+ TempRand = TempRand >> 8;
+ }
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Creates a 128bit random value that is fully forward and backward prediction resistant,
+ suitable for seeding a NIST SP800-90 Compliant, FIPS 1402-2 certifiable SW DRBG.
+ This function takes multiple random numbers through RDRAND without intervening
+ delays to ensure reseeding and performs AES-CBC-MAC over the data to compute the
+ seed value.
+
+ @param[out] SeedBuffer Pointer to a 128bit buffer to store the random seed.
+
+ @retval EFI_SUCCESS Random seed generation succeeded.
+ @retval EFI_NOT_READY Failed to request random bytes.
+
+**/
+EFI_STATUS
+EFIAPI
+RdRandGetSeed128 (
+ OUT UINT8 *SeedBuffer
+ )
+{
+ EFI_STATUS Status;
+ UINT8 RandByte[16];
+ UINT8 Key[16];
+ UINT8 Ffv[16];
+ UINT8 Xored[16];
+ UINT32 Index;
+ UINT32 Index2;
+
+ //
+ // Chose an arbitary key and zero the feed_forward_value (FFV)
+ //
+ for (Index = 0; Index < 16; Index++) {
+ Key[Index] = (UINT8) Index;
+ Ffv[Index] = 0;
+ }
+
+ //
+ // Perform CBC_MAC over 32 * 128 bit values, with 10us gaps between 128 bit value
+ // The 10us gaps will ensure multiple reseeds within the HW RNG with a large design margin.
+ //
+ for (Index = 0; Index < 32; Index++) {
+ MicroSecondDelay (10);
+ Status = RdRandGetBytes (16, RandByte);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+
+ //
+ // Perform XOR operations on two 128-bit value.
+ //
+ for (Index2 = 0; Index2 < 16; Index2++) {
+ Xored[Index2] = RandByte[Index2] ^ Ffv[Index2];
+ }
+
+ AesEncrypt (Key, Xored, Ffv);
+ }
+
+ for (Index = 0; Index < 16; Index++) {
+ SeedBuffer[Index] = Ffv[Index];
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Generate high-quality entropy source 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
+RdRandGenerateEntropy (
+ IN UINTN Length,
+ OUT UINT8 *Entropy
+ )
+{
+ EFI_STATUS Status;
+ UINTN BlockCount;
+ UINT8 Seed[16];
+ UINT8 *Ptr;
+
+ Status = EFI_NOT_READY;
+ BlockCount = Length / 16;
+ Ptr = (UINT8 *)Entropy;
+
+ //
+ // Generate high-quality seed for DRBG Entropy
+ //
+ while (BlockCount > 0) {
+ Status = RdRandGetSeed128 (Seed);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ CopyMem (Ptr, Seed, 16);
+
+ BlockCount--;
+ Ptr = Ptr + 16;
+ }
+
+ //
+ // Populate the remained data as request.
+ //
+ Status = RdRandGetSeed128 (Seed);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ CopyMem (Ptr, Seed, (Length % 16));
+
+ return Status;
+}
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