diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/X64/RdRand.S')
| -rw-r--r-- | MdePkg/Library/BaseLib/X64/RdRand.S | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/X64/RdRand.S b/MdePkg/Library/BaseLib/X64/RdRand.S new file mode 100644 index 0000000000000..0556979c25e14 --- /dev/null +++ b/MdePkg/Library/BaseLib/X64/RdRand.S @@ -0,0 +1,72 @@ +#------------------------------------------------------------------------------ ; +# Copyright (c) 2015 - 2016, 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 InternalX86RdRand16 (UINT16 *Rand); +//------------------------------------------------------------------------------ +ASM_GLOBAL ASM_PFX(InternalX86RdRand16) +ASM_PFX(InternalX86RdRand16): + .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 InternalX86RdRand32 (UINT32 *Rand); +//------------------------------------------------------------------------------ +ASM_GLOBAL ASM_PFX(InternalX86RdRand32) +ASM_PFX(InternalX86RdRand32): + .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 InternalX86RdRand64 (UINT64 *Rand); +//------------------------------------------------------------------------------ +ASM_GLOBAL ASM_PFX(InternalX86RdRand64) +ASM_PFX(InternalX86RdRand64): + .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 |