[PATCH 2/3] MdePkg: Refactor BaseRngLib to support AARCH64 in addition to X86


Rebecca Cran <rebecca@...>
 

Make BaseRngLib more generic by moving x86 specific functionality from
BaseRng.c into Rand/RdRand.c, and adding AArch64/Rndr.c, which supports
the optional ARMv8.5 RNG instructions RNDR and RNDRRS that are a part of
FEAT_RNG.

Signed-off-by: Rebecca Cran <rebecca@...>
---
MdePkg/MdePkg.dec | 9 +-
MdePkg/MdePkg.dsc | 4 +-
MdePkg/Library/BaseRngLib/BaseRngLib.inf | 16 ++-
MdePkg/Library/BaseRngLib/BaseRngLibInternals.h | 31 +++++
MdePkg/Library/BaseRngLib/AArch64/Rndr.c | 121 ++++++++++++++++++++
MdePkg/Library/BaseRngLib/BaseRng.c | 55 +++------
MdePkg/Library/BaseRngLib/Rand/RdRand.c | 103 +++++++++++++++++
MdePkg/Library/BaseRngLib/BaseRngLib.uni | 6 +-
8 files changed, 291 insertions(+), 54 deletions(-)

diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index 8965e903e093..b49f88d8e18f 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -267,6 +267,11 @@ [LibraryClasses]
#
RegisterFilterLib|Include/Library/RegisterFilterLib.h

+[LibraryClasses.IA32, LibraryClasses.X64, LibraryClasses.AARCH64]
+ ## @libraryclass Provides services to generate random number.
+ #
+ RngLib|Include/Library/RngLib.h
+
[LibraryClasses.IA32, LibraryClasses.X64]
## @libraryclass Abstracts both S/W SMI generation and detection.
##
@@ -288,10 +293,6 @@ [LibraryClasses.IA32, LibraryClasses.X64]
#
SmmPeriodicSmiLib|Include/Library/SmmPeriodicSmiLib.h

- ## @libraryclass Provides services to generate random number.
- #
- RngLib|Include/Library/RngLib.h
-
## @libraryclass Provides services to log the SMI handler registration.
SmiHandlerProfileLib|Include/Library/SmiHandlerProfileLib.h

diff --git a/MdePkg/MdePkg.dsc b/MdePkg/MdePkg.dsc
index d363419006ea..a94959169b2f 100644
--- a/MdePkg/MdePkg.dsc
+++ b/MdePkg/MdePkg.dsc
@@ -145,6 +145,9 @@ [Components.IA32, Components.X64, Components.ARM, Components.AARCH64]
MdePkg/Test/UnitTest/Library/BaseSafeIntLib/TestBaseSafeIntLibSmm.inf
MdePkg/Test/UnitTest/Library/BaseSafeIntLib/TestBaseSafeIntLibUefiShell.inf

+[Components.IA32, Components.X64, Components.AARCH64]
+ MdePkg/Library/BaseRngLib/BaseRngLib.inf
+
[Components.IA32, Components.X64]
MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsic.inf
MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf
@@ -168,7 +171,6 @@ [Components.IA32, Components.X64]
MdePkg/Library/BaseS3StallLib/BaseS3StallLib.inf
MdePkg/Library/SmmMemLib/SmmMemLib.inf
MdePkg/Library/SmmIoLib/SmmIoLib.inf
- MdePkg/Library/BaseRngLib/BaseRngLib.inf
MdePkg/Library/SmmPciExpressLib/SmmPciExpressLib.inf
MdePkg/Library/SmiHandlerProfileLibNull/SmiHandlerProfileLibNull.inf
MdePkg/Library/MmServicesTableLib/MmServicesTableLib.inf
diff --git a/MdePkg/Library/BaseRngLib/BaseRngLib.inf b/MdePkg/Library/BaseRngLib/BaseRngLib.inf
index 31740751c69c..1dc3249a8c20 100644
--- a/MdePkg/Library/BaseRngLib/BaseRngLib.inf
+++ b/MdePkg/Library/BaseRngLib/BaseRngLib.inf
@@ -1,9 +1,10 @@
## @file
# Instance of RNG (Random Number Generator) Library.
#
-# BaseRng Library that uses CPU RdRand instruction access to provide
-# high-quality random numbers.
+# BaseRng Library that uses CPU RNG instructions (e.g. RdRand) to
+# provide high-quality random numbers.
#
+# Copyright (c) 2020, NUVIA Inc. All rights reserved.<BR>
# Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
#
# SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -22,11 +23,18 @@ [Defines]
CONSTRUCTOR = BaseRngLibConstructor

#
-# VALID_ARCHITECTURES = IA32 X64
+# VALID_ARCHITECTURES = IA32 X64 AARCH64
#

-[Sources.Ia32, Sources.X64]
+[Sources]
BaseRng.c
+ BaseRngLibInternals.h
+
+[Sources.Ia32, Sources.X64]
+ Rand/RdRand.c
+
+[Sources.AARCH64]
+ AArch64/Rndr.c

[Packages]
MdePkg/MdePkg.dec
diff --git a/MdePkg/Library/BaseRngLib/BaseRngLibInternals.h b/MdePkg/Library/BaseRngLib/BaseRngLibInternals.h
new file mode 100644
index 000000000000..44fda69c9eec
--- /dev/null
+++ b/MdePkg/Library/BaseRngLib/BaseRngLibInternals.h
@@ -0,0 +1,31 @@
+/** @file
+
+ Architecture specific interface to RNG functionality.
+
+Copyright (c) 2020, NUVIA Inc. All rights reserved.<BR>
+
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef BASE_RNGLIB_INTERNALS_H_
+
+BOOLEAN
+EFIAPI
+ArchGetRandomNumber16 (
+ OUT UINT16 *Rand
+ );
+
+BOOLEAN
+EFIAPI
+ArchGetRandomNumber32 (
+ OUT UINT32 *Rand
+ );
+
+BOOLEAN
+EFIAPI
+ArchGetRandomNumber64 (
+ OUT UINT64 *Rand
+ );
+
+#endif // BASE_RNGLIB_INTERNALS_H_
diff --git a/MdePkg/Library/BaseRngLib/AArch64/Rndr.c b/MdePkg/Library/BaseRngLib/AArch64/Rndr.c
new file mode 100644
index 000000000000..19643237923a
--- /dev/null
+++ b/MdePkg/Library/BaseRngLib/AArch64/Rndr.c
@@ -0,0 +1,121 @@
+/** @file
+ Random number generator service that uses the RNDR instruction
+ to provide high-quality random numbers.
+
+ Copyright (c) 2020, NUVIA Inc. All rights reserved.<BR>
+ Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+#include <Library/RngLib.h>
+
+#include "BaseRngLibInternals.h"
+
+//
+// Bit mask used to determine if RNDR instruction is supported.
+//
+#define RNDR_MASK ((UINT64)MAX_UINT16 << 60U)
+
+/**
+ The constructor function checks whether or not RNDR instruction is supported
+ by the host hardware.
+
+ The constructor function checks whether or not RNDR instruction is supported.
+ It will ASSERT() if RNDR instruction is not supported.
+ It will always return RETURN_SUCCESS.
+
+ @retval RETURN_SUCCESS The constructor always returns EFI_SUCCESS.
+
+**/
+RETURN_STATUS
+EFIAPI
+BaseRngLibConstructor (
+ VOID
+ )
+{
+ UINT64 Isar0;
+ //
+ // Determine RNDR support by examining bits 63:60 of the ISAR0 register returned by
+ // MSR. A non-zero value indicates that the processor supports the RNDR instruction.
+ //
+ Isar0 = ArmReadIdIsar0 ();
+ ASSERT ((Isar0 & RNDR_MASK) != 0);
+ (void)Isar0;
+
+ return RETURN_SUCCESS;
+}
+
+
+/**
+ Generates a 16-bit random number.
+
+ @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
+ArchGetRandomNumber16 (
+ OUT UINT16 *Rand
+ )
+{
+ UINT64 Rand64;
+
+ if (ArchGetRandomNumber64 (&Rand64)) {
+ *Rand = Rand64 & MAX_UINT16;
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Generates a 32-bit random number.
+
+ @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
+ArchGetRandomNumber32 (
+ OUT UINT32 *Rand
+ )
+{
+ UINT64 Rand64;
+
+ if (ArchGetRandomNumber64 (&Rand64)) {
+ *Rand = Rand64 & MAX_UINT32;
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Generates a 64-bit random number.
+
+ @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
+ArchGetRandomNumber64 (
+ OUT UINT64 *Rand
+ )
+{
+ return ArmRndr (Rand);
+}
+
diff --git a/MdePkg/Library/BaseRngLib/BaseRng.c b/MdePkg/Library/BaseRngLib/BaseRng.c
index 7ad7aec9d38f..072fa37d3394 100644
--- a/MdePkg/Library/BaseRngLib/BaseRng.c
+++ b/MdePkg/Library/BaseRngLib/BaseRng.c
@@ -1,8 +1,10 @@
/** @file
- Random number generator services that uses RdRand instruction access
- to provide high-quality random numbers.
+ Random number generator services that uses CPU RNG instructions to
+ provide high-quality random numbers.

+Copyright (c) 2021, NUVIA Inc. All rights reserved.<BR>
Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
+
SPDX-License-Identifier: BSD-2-Clause-Patent

**/
@@ -10,46 +12,15 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>

-//
-// Bit mask used to determine if RdRand instruction is supported.
-//
-#define RDRAND_MASK BIT30
+#include "BaseRngLibInternals.h"

//
// Limited retry number when valid random data is returned.
// Uses the recommended value defined in Section 7.3.17 of "Intel 64 and IA-32
-// Architectures Software Developer's Mannual".
+// Architectures Software Developer's Manual".
//
-#define RDRAND_RETRY_LIMIT 10
+#define GETRANDOM_RETRY_LIMIT 10

-/**
- The constructor function checks whether or not RDRAND instruction is supported
- by the host hardware.
-
- The constructor function checks whether or not RDRAND instruction is supported.
- It will ASSERT() if RDRAND instruction is not supported.
- It will always return RETURN_SUCCESS.
-
- @retval RETURN_SUCCESS The constructor always returns EFI_SUCCESS.
-
-**/
-RETURN_STATUS
-EFIAPI
-BaseRngLibConstructor (
- VOID
- )
-{
- UINT32 RegEcx;
-
- //
- // Determine RDRAND support by examining bit 30 of the ECX register returned by
- // CPUID. A value of 1 indicates that processor support RDRAND instruction.
- //
- AsmCpuid (1, 0, 0, &RegEcx, 0);
- ASSERT ((RegEcx & RDRAND_MASK) == RDRAND_MASK);
-
- return RETURN_SUCCESS;
-}

/**
Generates a 16-bit random number.
@@ -75,8 +46,8 @@ GetRandomNumber16 (
//
// A loop to fetch a 16 bit random value with a retry count limit.
//
- for (Index = 0; Index < RDRAND_RETRY_LIMIT; Index++) {
- if (AsmRdRand16 (Rand)) {
+ for (Index = 0; Index < GETRANDOM_RETRY_LIMIT; Index++) {
+ if (ArchGetRandomNumber16 (Rand)) {
return TRUE;
}
}
@@ -108,8 +79,8 @@ GetRandomNumber32 (
//
// A loop to fetch a 32 bit random value with a retry count limit.
//
- for (Index = 0; Index < RDRAND_RETRY_LIMIT; Index++) {
- if (AsmRdRand32 (Rand)) {
+ for (Index = 0; Index < GETRANDOM_RETRY_LIMIT; Index++) {
+ if (ArchGetRandomNumber32 (Rand)) {
return TRUE;
}
}
@@ -141,8 +112,8 @@ GetRandomNumber64 (
//
// A loop to fetch a 64 bit random value with a retry count limit.
//
- for (Index = 0; Index < RDRAND_RETRY_LIMIT; Index++) {
- if (AsmRdRand64 (Rand)) {
+ for (Index = 0; Index < GETRANDOM_RETRY_LIMIT; Index++) {
+ if (ArchGetRandomNumber64 (Rand)) {
return TRUE;
}
}
diff --git a/MdePkg/Library/BaseRngLib/Rand/RdRand.c b/MdePkg/Library/BaseRngLib/Rand/RdRand.c
new file mode 100644
index 000000000000..3f1378064b4c
--- /dev/null
+++ b/MdePkg/Library/BaseRngLib/Rand/RdRand.c
@@ -0,0 +1,103 @@
+/** @file
+ Random number generator services that uses RdRand instruction access
+ to provide high-quality random numbers.
+
+Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
+
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+#include "BaseRngLibInternals.h"
+
+//
+// Bit mask used to determine if RdRand instruction is supported.
+//
+#define RDRAND_MASK BIT30
+
+/**
+ The constructor function checks whether or not RDRAND instruction is supported
+ by the host hardware.
+
+ The constructor function checks whether or not RDRAND instruction is supported.
+ It will ASSERT() if RDRAND instruction is not supported.
+ It will always return RETURN_SUCCESS.
+
+ @retval RETURN_SUCCESS The constructor always returns EFI_SUCCESS.
+
+**/
+RETURN_STATUS
+EFIAPI
+BaseRngLibConstructor (
+ VOID
+ )
+{
+ UINT32 RegEcx;
+
+ //
+ // Determine RDRAND support by examining bit 30 of the ECX register returned by
+ // CPUID. A value of 1 indicates that processor support RDRAND instruction.
+ //
+ AsmCpuid (1, 0, 0, &RegEcx, 0);
+ ASSERT ((RegEcx & RDRAND_MASK) == RDRAND_MASK);
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Generates a 16-bit random number.
+
+ @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
+ArchGetRandomNumber16 (
+ OUT UINT16 *Rand
+ )
+{
+ return AsmRdRand16 (Rand);
+}
+
+/**
+ Generates a 32-bit random number.
+
+ @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
+ArchGetRandomNumber32 (
+ OUT UINT32 *Rand
+ )
+{
+ return AsmRdRand32 (Rand);
+}
+
+/**
+ Generates a 64-bit random number.
+
+ @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
+ArchGetRandomNumber64 (
+ OUT UINT64 *Rand
+ )
+{
+ return AsmRdRand64 (Rand);
+}
+
diff --git a/MdePkg/Library/BaseRngLib/BaseRngLib.uni b/MdePkg/Library/BaseRngLib/BaseRngLib.uni
index f3ed954c5209..8c7fe1219450 100644
--- a/MdePkg/Library/BaseRngLib/BaseRngLib.uni
+++ b/MdePkg/Library/BaseRngLib/BaseRngLib.uni
@@ -1,8 +1,8 @@
// /** @file
// Instance of RNG (Random Number Generator) Library.
//
-// BaseRng Library that uses CPU RdRand instruction access to provide
-// high-quality random numbers.
+// BaseRng Library that uses CPU RNG instructions to provide high-quality
+// random numbers.
//
// Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
//
@@ -13,5 +13,5 @@

#string STR_MODULE_ABSTRACT #language en-US "Instance of RNG Library"

-#string STR_MODULE_DESCRIPTION #language en-US "BaseRng Library that uses CPU RdRand instruction access to provide high-quality random numbers"
+#string STR_MODULE_DESCRIPTION #language en-US "BaseRng Library that uses CPU RNG instructions to provide high-quality random numbers"

--
2.26.2

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