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MdePkg: Add CPU RdRand access APIs for random number generation

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Add AsmRdRand16/32/64 APIs for RdRand instruction access to generate
high-quality random number.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Qin Long <qin.long@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18518 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Qin Long
2015-09-21 05:53:52 +00:00
committed by qlong
parent 82f3edf26a
commit 3cfc7813bb
6 changed files with 386 additions and 0 deletions
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72
MdePkg/Library/BaseLib/X64/RdRand.S Normal file
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#------------------------------------------------------------------------------ ;
# Copyright (c) 2015, 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.
#
# Module Name:
#
# RdRand.S
#
# Abstract:
#
# Generates random number through CPU RdRand instruction under 64-bit platform.
#
# Notes:
#
#------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// Generates a 16 bit random number through RDRAND instruction.
// Return TRUE if Rand generated successfully, or FALSE if not.
//
// BOOLEAN EFIAPI AsmRdRand16 (UINT16 *Rand);
//------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(AsmRdRand16)
ASM_PFX(AsmRdRand16):
.byte 0x0f, 0xc7, 0xf0 // rdrand r16: "0f c7 /6 ModRM:r/m(w)"
jc rn16_ok // jmp if CF=1
xor %rax, %rax // reg=0 if CF=0
ret // return with failure status
rn16_ok:
mov %ax, (%rcx)
mov $0x1, %rax
ret
//------------------------------------------------------------------------------
// Generates a 32 bit random number through RDRAND instruction.
// Return TRUE if Rand generated successfully, or FALSE if not.
//
// BOOLEAN EFIAPI AsmRdRand32 (UINT32 *Rand);
//------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(AsmRdRand32)
ASM_PFX(AsmRdRand32):
.byte 0x0f, 0xc7, 0xf0 // rdrand r32: "0f c7 /6 ModRM:r/m(w)"
jc rn32_ok // jmp if CF=1
xor %rax, %rax // reg=0 if CF=0
ret // return with failure status
rn32_ok:
mov %eax, (%rcx)
mov $0x1, %rax
ret
//------------------------------------------------------------------------------
// Generates a 64 bit random number through RDRAND instruction.
// Return TRUE if Rand generated successfully, or FALSE if not.
//
// BOOLEAN EFIAPI AsmRdRand64 (UINT64 *Rand);
//------------------------------------------------------------------------------
ASM_GLOBAL ASM_PFX(AsmRdRand64)
ASM_PFX(AsmRdRand64):
.byte 0x48, 0x0f, 0xc7, 0xf0 // rdrand r64: "REX.W + 0f c7 /6 ModRM:r/m(w)"
jc rn64_ok // jmp if CF=1
xor %rax, %rax // reg=0 if CF=0
ret // return with failure status
rn64_ok:
mov %rax, (%rcx)
mov $0x1, %rax
ret