Declare GetRandomNumber128 in RngLib.h.
Create GetRandomNumber128 in BaseRngLib, which is simply calling
GetRandomNumber64 twice
A GetRandomNumber128 function allows platforms with 128bit HWRNGs to save on IO
overhead that comes from having to prime the HWRNG device before each read
operation. Using the HWRNG installed on the HP ProLiant m400 moonshot
cartridge, this will save about 50ms per RAW Entropy operation as compared with
calling GetRandomNumber64 twice.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Thomas Palmer <thomas.pal...@hpe.com>
---
MdePkg/Include/Library/RngLib.h | 17 +++++++++++++++++
MdePkg/Library/BaseRngLib/BaseRng.c | 32 ++++++++++++++++++++++++++++++++
2 files changed, 49 insertions(+)
diff --git a/MdePkg/Include/Library/RngLib.h b/MdePkg/Include/Library/RngLib.h
index 157a931..ece4394 100644
--- a/MdePkg/Include/Library/RngLib.h
+++ b/MdePkg/Include/Library/RngLib.h
@@ -66,4 +66,21 @@ GetRandomNumber64 (
OUT UINT64 *Rand
);
+/**
+ 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
+ );
+
#endif // __RNG_LIB_H__
diff --git a/MdePkg/Library/BaseRngLib/BaseRng.c
b/MdePkg/Library/BaseRngLib/BaseRng.c
index 279df30..2c8df56 100644
--- a/MdePkg/Library/BaseRngLib/BaseRng.c
+++ b/MdePkg/Library/BaseRngLib/BaseRng.c
@@ -155,3 +155,35 @@ GetRandomNumber64 (
return FALSE;
}
+
+/**
+ 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);
+
+ //
+ // Read first 64 bits
+ //
+ if (!GetRandomNumber64 (Rand)) {
+ return FALSE;
+ }
+
+ //
+ // Read second 64 bits
+ //
+ return GetRandomNumber64 (++Rand);
+}
--
1.7.9.5
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