diff options
Diffstat (limited to 'MdeModulePkg/Library/BaseRngLibTimerLib')
3 files changed, 275 insertions, 275 deletions
diff --git a/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.inf b/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.inf index 8461260cc8..b11bbdd054 100644 --- a/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.inf +++ b/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.inf @@ -1,40 +1,40 @@ -## @file
-# Instance of RNG (Random Number Generator) Library.
-#
-# BaseRng Library that uses the TimerLib to provide reasonably random numbers.
-# Do NOT use this on a production system as this uses the system performance
-# counter rather than a true source of random in addition to having a weak
-# random algorithm. This is provided primarily as a source of entropy for
-# OpenSSL for platforms that do not have a good built in RngLib as this
-# emulates what was done before (though it isn't perfect).
-#
-# Copyright (c) Microsoft Corporation. All rights reserved.<BR>
-#
-# SPDX-License-Identifier: BSD-2-Clause-Patent
-#
-#
-##
-
-[Defines]
- INF_VERSION = 1.27
- BASE_NAME = BaseRngLibTimerLib
- MODULE_UNI_FILE = BaseRngLibTimerLib.uni
- FILE_GUID = B3E66B05-D218-4B9A-AC33-EF0F83D6A513
- MODULE_TYPE = BASE
- VERSION_STRING = 1.0
- LIBRARY_CLASS = RngLib
-
-[Sources]
- RngLibTimer.c
-
-[Packages]
- MdePkg/MdePkg.dec
- MdeModulePkg/MdeModulePkg.dec
-
-[Guids]
- gEdkiiRngAlgorithmUnSafe
-
-[LibraryClasses]
- BaseLib
- DebugLib
- TimerLib
+## @file +# Instance of RNG (Random Number Generator) Library. +# +# BaseRng Library that uses the TimerLib to provide reasonably random numbers. +# Do NOT use this on a production system as this uses the system performance +# counter rather than a true source of random in addition to having a weak +# random algorithm. This is provided primarily as a source of entropy for +# OpenSSL for platforms that do not have a good built in RngLib as this +# emulates what was done before (though it isn't perfect). +# +# Copyright (c) Microsoft Corporation. All rights reserved.<BR> +# +# SPDX-License-Identifier: BSD-2-Clause-Patent +# +# +## + +[Defines] + INF_VERSION = 1.27 + BASE_NAME = BaseRngLibTimerLib + MODULE_UNI_FILE = BaseRngLibTimerLib.uni + FILE_GUID = B3E66B05-D218-4B9A-AC33-EF0F83D6A513 + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = RngLib + +[Sources] + RngLibTimer.c + +[Packages] + MdePkg/MdePkg.dec + MdeModulePkg/MdeModulePkg.dec + +[Guids] + gEdkiiRngAlgorithmUnSafe + +[LibraryClasses] + BaseLib + DebugLib + TimerLib diff --git a/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.uni b/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.uni index fde24b9f01..dd0e4b3050 100644 --- a/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.uni +++ b/MdeModulePkg/Library/BaseRngLibTimerLib/BaseRngLibTimerLib.uni @@ -1,15 +1,15 @@ -// @file
-// Instance of RNG (Random Number Generator) Library.
-//
-// RngLib that uses TimerLib's performance counter to provide random numbers.
-//
-// Copyright (c) Microsoft Corporation.
-//
-// SPDX-License-Identifier: BSD-2-Clause-Patent
-//
-
-
-#string STR_MODULE_ABSTRACT #language en-US "Instance of RNG Library"
-
-#string STR_MODULE_DESCRIPTION #language en-US "BaseRng Library that uses the TimerLib to provide low-entropy random numbers"
-
+// @file +// Instance of RNG (Random Number Generator) Library. +// +// RngLib that uses TimerLib's performance counter to provide random numbers. +// +// Copyright (c) Microsoft Corporation. +// +// SPDX-License-Identifier: BSD-2-Clause-Patent +// + + +#string STR_MODULE_ABSTRACT #language en-US "Instance of RNG Library" + +#string STR_MODULE_DESCRIPTION #language en-US "BaseRng Library that uses the TimerLib to provide low-entropy random numbers" + diff --git a/MdeModulePkg/Library/BaseRngLibTimerLib/RngLibTimer.c b/MdeModulePkg/Library/BaseRngLibTimerLib/RngLibTimer.c index 28ff46c71f..4d3b1617de 100644 --- a/MdeModulePkg/Library/BaseRngLibTimerLib/RngLibTimer.c +++ b/MdeModulePkg/Library/BaseRngLibTimerLib/RngLibTimer.c @@ -1,220 +1,220 @@ -/** @file
- BaseRng Library that uses the TimerLib to provide reasonably random numbers.
- Do not use this on a production system.
-
- Copyright (c) 2023, Arm Limited. All rights reserved.
- Copyright (c) Microsoft Corporation.
- SPDX-License-Identifier: BSD-2-Clause-Patent
-**/
-
-#include <Base.h>
-#include <Uefi.h>
-#include <Library/BaseLib.h>
-#include <Library/BaseMemoryLib.h>
-#include <Library/DebugLib.h>
-#include <Library/TimerLib.h>
-#include <Guid/RngAlgorithm.h>
-
-#define DEFAULT_DELAY_TIME_IN_MICROSECONDS 10
-
-/**
- Using the TimerLib GetPerformanceCounterProperties() we delay
- for enough time for the PerformanceCounter to increment.
-
- If the return value from GetPerformanceCounterProperties (TimerLib)
- is zero, this function will return 10 and attempt to assert.
- **/
-STATIC
-UINT32
-CalculateMinimumDecentDelayInMicroseconds (
- VOID
- )
-{
- UINT64 CounterHz;
-
- // Get the counter properties
- CounterHz = GetPerformanceCounterProperties (NULL, NULL);
- // Make sure we won't divide by zero
- if (CounterHz == 0) {
- ASSERT (CounterHz != 0); // Assert so the developer knows something is wrong
- return DEFAULT_DELAY_TIME_IN_MICROSECONDS;
- }
-
- // Calculate the minimum delay based on 1.5 microseconds divided by the hertz.
- // We calculate the length of a cycle (1/CounterHz) and multiply it by 1.5 microseconds
- // This ensures that the performance counter has increased by at least one
- return (UINT32)(MAX (DivU64x64Remainder (1500000, CounterHz, NULL), 1));
-}
-
-/**
- Generates a 16-bit random number.
-
- if Rand is NULL, then ASSERT().
-
- @param[out] Rand Buffer pointer to store the 16-bit random value.
-
- @retval TRUE Random number generated successfully.
- @retval FALSE Failed to generate the random number.
-
-**/
-BOOLEAN
-EFIAPI
-GetRandomNumber16 (
- OUT UINT16 *Rand
- )
-{
- UINT32 Index;
- UINT8 *RandPtr;
- UINT32 DelayInMicroSeconds;
-
- ASSERT (Rand != NULL);
-
- if (Rand == NULL) {
- return FALSE;
- }
-
- DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds ();
- RandPtr = (UINT8 *)Rand;
- // Get 2 bytes of random ish data
- for (Index = 0; Index < sizeof (UINT16); Index++) {
- *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF);
- // Delay to give the performance counter a chance to change
- MicroSecondDelay (DelayInMicroSeconds);
- RandPtr++;
- }
-
- return TRUE;
-}
-
-/**
- Generates a 32-bit random number.
-
- if Rand is NULL, then ASSERT().
-
- @param[out] Rand Buffer pointer to store the 32-bit random value.
-
- @retval TRUE Random number generated successfully.
- @retval FALSE Failed to generate the random number.
-
-**/
-BOOLEAN
-EFIAPI
-GetRandomNumber32 (
- OUT UINT32 *Rand
- )
-{
- UINT32 Index;
- UINT8 *RandPtr;
- UINT32 DelayInMicroSeconds;
-
- ASSERT (Rand != NULL);
-
- if (NULL == Rand) {
- return FALSE;
- }
-
- RandPtr = (UINT8 *)Rand;
- DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds ();
- // Get 4 bytes of random ish data
- for (Index = 0; Index < sizeof (UINT32); Index++) {
- *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF);
- // Delay to give the performance counter a chance to change
- MicroSecondDelay (DelayInMicroSeconds);
- RandPtr++;
- }
-
- return TRUE;
-}
-
-/**
- Generates a 64-bit random number.
-
- if Rand is NULL, then ASSERT().
-
- @param[out] Rand Buffer pointer to store the 64-bit random value.
-
- @retval TRUE Random number generated successfully.
- @retval FALSE Failed to generate the random number.
-
-**/
-BOOLEAN
-EFIAPI
-GetRandomNumber64 (
- OUT UINT64 *Rand
- )
-{
- UINT32 Index;
- UINT8 *RandPtr;
- UINT32 DelayInMicroSeconds;
-
- ASSERT (Rand != NULL);
-
- if (NULL == Rand) {
- return FALSE;
- }
-
- RandPtr = (UINT8 *)Rand;
- DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds ();
- // Get 8 bytes of random ish data
- for (Index = 0; Index < sizeof (UINT64); Index++) {
- *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF);
- // Delay to give the performance counter a chance to change
- MicroSecondDelay (DelayInMicroSeconds);
- RandPtr++;
- }
-
- return TRUE;
-}
-
-/**
- Generates a 128-bit random number.
-
- if Rand is NULL, then ASSERT().
-
- @param[out] Rand Buffer pointer to store the 128-bit random value.
-
- @retval TRUE Random number generated successfully.
- @retval FALSE Failed to generate the random number.
-
-**/
-BOOLEAN
-EFIAPI
-GetRandomNumber128 (
- OUT UINT64 *Rand
- )
-{
- ASSERT (Rand != NULL);
- // This should take around 80ms
-
- // Read first 64 bits
- if (!GetRandomNumber64 (Rand)) {
- return FALSE;
- }
-
- // Read second 64 bits
- return GetRandomNumber64 (++Rand);
-}
-
-/**
- Get a GUID identifying the RNG algorithm implementation.
-
- @param [out] RngGuid If success, contains the GUID identifying
- the RNG algorithm implementation.
-
- @retval EFI_SUCCESS Success.
- @retval EFI_UNSUPPORTED Not supported.
- @retval EFI_INVALID_PARAMETER Invalid parameter.
-**/
-EFI_STATUS
-EFIAPI
-GetRngGuid (
- GUID *RngGuid
- )
-{
- if (RngGuid == NULL) {
- return EFI_INVALID_PARAMETER;
- }
-
- CopyMem (RngGuid, &gEdkiiRngAlgorithmUnSafe, sizeof (*RngGuid));
- return EFI_SUCCESS;
-}
+/** @file + BaseRng Library that uses the TimerLib to provide reasonably random numbers. + Do not use this on a production system. + + Copyright (c) 2023, Arm Limited. All rights reserved. + Copyright (c) Microsoft Corporation. + SPDX-License-Identifier: BSD-2-Clause-Patent +**/ + +#include <Base.h> +#include <Uefi.h> +#include <Library/BaseLib.h> +#include <Library/BaseMemoryLib.h> +#include <Library/DebugLib.h> +#include <Library/TimerLib.h> +#include <Guid/RngAlgorithm.h> + +#define DEFAULT_DELAY_TIME_IN_MICROSECONDS 10 + +/** + Using the TimerLib GetPerformanceCounterProperties() we delay + for enough time for the PerformanceCounter to increment. + + If the return value from GetPerformanceCounterProperties (TimerLib) + is zero, this function will return 10 and attempt to assert. + **/ +STATIC +UINT32 +CalculateMinimumDecentDelayInMicroseconds ( + VOID + ) +{ + UINT64 CounterHz; + + // Get the counter properties + CounterHz = GetPerformanceCounterProperties (NULL, NULL); + // Make sure we won't divide by zero + if (CounterHz == 0) { + ASSERT (CounterHz != 0); // Assert so the developer knows something is wrong + return DEFAULT_DELAY_TIME_IN_MICROSECONDS; + } + + // Calculate the minimum delay based on 1.5 microseconds divided by the hertz. + // We calculate the length of a cycle (1/CounterHz) and multiply it by 1.5 microseconds + // This ensures that the performance counter has increased by at least one + return (UINT32)(MAX (DivU64x64Remainder (1500000, CounterHz, NULL), 1)); +} + +/** + Generates a 16-bit random number. + + if Rand is NULL, then ASSERT(). + + @param[out] Rand Buffer pointer to store the 16-bit random value. + + @retval TRUE Random number generated successfully. + @retval FALSE Failed to generate the random number. + +**/ +BOOLEAN +EFIAPI +GetRandomNumber16 ( + OUT UINT16 *Rand + ) +{ + UINT32 Index; + UINT8 *RandPtr; + UINT32 DelayInMicroSeconds; + + ASSERT (Rand != NULL); + + if (Rand == NULL) { + return FALSE; + } + + DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds (); + RandPtr = (UINT8 *)Rand; + // Get 2 bytes of random ish data + for (Index = 0; Index < sizeof (UINT16); Index++) { + *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF); + // Delay to give the performance counter a chance to change + MicroSecondDelay (DelayInMicroSeconds); + RandPtr++; + } + + return TRUE; +} + +/** + Generates a 32-bit random number. + + if Rand is NULL, then ASSERT(). + + @param[out] Rand Buffer pointer to store the 32-bit random value. + + @retval TRUE Random number generated successfully. + @retval FALSE Failed to generate the random number. + +**/ +BOOLEAN +EFIAPI +GetRandomNumber32 ( + OUT UINT32 *Rand + ) +{ + UINT32 Index; + UINT8 *RandPtr; + UINT32 DelayInMicroSeconds; + + ASSERT (Rand != NULL); + + if (NULL == Rand) { + return FALSE; + } + + RandPtr = (UINT8 *)Rand; + DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds (); + // Get 4 bytes of random ish data + for (Index = 0; Index < sizeof (UINT32); Index++) { + *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF); + // Delay to give the performance counter a chance to change + MicroSecondDelay (DelayInMicroSeconds); + RandPtr++; + } + + return TRUE; +} + +/** + Generates a 64-bit random number. + + if Rand is NULL, then ASSERT(). + + @param[out] Rand Buffer pointer to store the 64-bit random value. + + @retval TRUE Random number generated successfully. + @retval FALSE Failed to generate the random number. + +**/ +BOOLEAN +EFIAPI +GetRandomNumber64 ( + OUT UINT64 *Rand + ) +{ + UINT32 Index; + UINT8 *RandPtr; + UINT32 DelayInMicroSeconds; + + ASSERT (Rand != NULL); + + if (NULL == Rand) { + return FALSE; + } + + RandPtr = (UINT8 *)Rand; + DelayInMicroSeconds = CalculateMinimumDecentDelayInMicroseconds (); + // Get 8 bytes of random ish data + for (Index = 0; Index < sizeof (UINT64); Index++) { + *RandPtr = (UINT8)(GetPerformanceCounter () & 0xFF); + // Delay to give the performance counter a chance to change + MicroSecondDelay (DelayInMicroSeconds); + RandPtr++; + } + + return TRUE; +} + +/** + Generates a 128-bit random number. + + if Rand is NULL, then ASSERT(). + + @param[out] Rand Buffer pointer to store the 128-bit random value. + + @retval TRUE Random number generated successfully. + @retval FALSE Failed to generate the random number. + +**/ +BOOLEAN +EFIAPI +GetRandomNumber128 ( + OUT UINT64 *Rand + ) +{ + ASSERT (Rand != NULL); + // This should take around 80ms + + // Read first 64 bits + if (!GetRandomNumber64 (Rand)) { + return FALSE; + } + + // Read second 64 bits + return GetRandomNumber64 (++Rand); +} + +/** + Get a GUID identifying the RNG algorithm implementation. + + @param [out] RngGuid If success, contains the GUID identifying + the RNG algorithm implementation. + + @retval EFI_SUCCESS Success. + @retval EFI_UNSUPPORTED Not supported. + @retval EFI_INVALID_PARAMETER Invalid parameter. +**/ +EFI_STATUS +EFIAPI +GetRngGuid ( + GUID *RngGuid + ) +{ + if (RngGuid == NULL) { + return EFI_INVALID_PARAMETER; + } + + CopyMem (RngGuid, &gEdkiiRngAlgorithmUnSafe, sizeof (*RngGuid)); + return EFI_SUCCESS; +} |