-#------------------------------------------------------------------------------ ;\r
-# Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR>\r
-# This program and the accompanying materials\r
-# are licensed and made available under the terms and conditions of the BSD License\r
-# which accompanies this distribution. The full text of the license may be found at\r
-# http://opensource.org/licenses/bsd-license.php.\r
-#\r
-# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
-# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
-#\r
-# Module Name:\r
-#\r
-# RdRand.S\r
-#\r
-# Abstract:\r
-#\r
-# Generates random number through CPU RdRand instruction under 32-bit platform.\r
-#\r
-# Notes:\r
-#\r
-#------------------------------------------------------------------------------\r
-\r
-//------------------------------------------------------------------------------\r
-// Generates a 16 bit random number through RDRAND instruction.\r
-// Return TRUE if Rand generated successfully, or FALSE if not.\r
-//\r
-// BOOLEAN EFIAPI InternalX86RdRand16 (UINT16 *Rand);\r
-//------------------------------------------------------------------------------\r
-ASM_GLOBAL ASM_PFX(InternalX86RdRand16)\r
-ASM_PFX(InternalX86RdRand16):\r
- .byte 0x0f, 0xc7, 0xf0 // rdrand r16: "0f c7 /6 ModRM:r/m(w)"\r
- jc rn16_ok // jmp if CF=1\r
- xor %eax, %eax // reg=0 if CF=0\r
- ret // return with failure status\r
-rn16_ok:\r
- mov 0x4(%esp), %edx\r
- mov %ax, (%edx)\r
- mov $0x1, %eax\r
- ret\r
-\r
-//------------------------------------------------------------------------------\r
-// Generates a 32 bit random number through RDRAND instruction.\r
-// Return TRUE if Rand generated successfully, or FALSE if not.\r
-//\r
-// BOOLEAN EFIAPI InternalX86RdRand32 (UINT32 *Rand);\r
-//------------------------------------------------------------------------------\r
-ASM_GLOBAL ASM_PFX(InternalX86RdRand32)\r
-ASM_PFX(InternalX86RdRand32):\r
- .byte 0x0f, 0xc7, 0xf0 // rdrand r32: "0f c7 /6 ModRM:r/m(w)"\r
- jc rn32_ok // jmp if CF=1\r
- xor %eax, %eax // reg=0 if CF=0\r
- ret // return with failure status\r
-rn32_ok:\r
- mov 0x4(%esp), %edx\r
- mov %eax, (%edx)\r
- mov $0x1, %eax\r
- ret\r
-\r
-//------------------------------------------------------------------------------\r
-// Generates a 64 bit random number through RDRAND instruction.\r
-// Return TRUE if Rand generated successfully, or FALSE if not.\r
-//\r
-// BOOLEAN EFIAPI InternalX86RdRand64 (UINT64 *Rand);\r
-//------------------------------------------------------------------------------\r
-ASM_GLOBAL ASM_PFX(InternalX86RdRand64)\r
-ASM_PFX(InternalX86RdRand64):\r
- .byte 0x0f, 0xc7, 0xf0 // rdrand r32: "0f c7 /6 ModRM:r/m(w)"\r
- jnc rn64_ret // jmp if CF=0\r
- mov 0x4(%esp), %edx\r
- mov %eax, (%edx)\r
-\r
- .byte 0x0f, 0xc7, 0xf0 // generate another 32 bit RN\r
- jnc rn64_ret // jmp if CF=0\r
- mov %eax, 0x4(%edx)\r
-\r
- mov $0x1, %eax\r
- ret\r
-rn64_ret:\r
- xor %eax, %eax\r
- ret // return with failure status\r