projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| f493cf81 JJ |
1 | ;------------------------------------------------------------------------------\r |
| 2 | ;\r | |
| 0aac2f77 | 3 | ; Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>\r |
| 9344f092 | 4 | ; SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| f493cf81 JJ |
5 | ;\r |
| 6 | ; Module Name:\r | |
| 7 | ;\r | |
| 8 | ; LongJump.Asm\r | |
| 9 | ;\r | |
| 10 | ; Abstract:\r | |
| 11 | ;\r | |
| 12 | ; Implementation of _LongJump() on IA-32.\r | |
| 13 | ;\r | |
| 14 | ;------------------------------------------------------------------------------\r | |
| 15 | \r | |
| 0aac2f77 JY |
16 | %include "Nasm.inc"\r |
| 17 | \r | |
| f493cf81 JJ |
18 | SECTION .text\r |
| 19 | \r | |
| 0aac2f77 JY |
20 | extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))\r |
| 21 | \r | |
| f493cf81 JJ |
22 | ;------------------------------------------------------------------------------\r |
| 23 | ; VOID\r | |
| 24 | ; EFIAPI\r | |
| 25 | ; InternalLongJump (\r | |
| 26 | ; IN BASE_LIBRARY_JUMP_BUFFER *JumpBuffer,\r | |
| 27 | ; IN UINTN Value\r | |
| 28 | ; );\r | |
| 29 | ;------------------------------------------------------------------------------\r | |
| 30 | global ASM_PFX(InternalLongJump)\r | |
| 31 | ASM_PFX(InternalLongJump):\r | |
| 0aac2f77 JY |
32 | \r |
| 33 | mov eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]\r | |
| 34 | test eax, eax\r | |
| 35 | jz CetDone\r | |
| 36 | mov eax, cr4\r | |
| 37 | bt eax, 23 ; check if CET is enabled\r | |
| 38 | jnc CetDone\r | |
| 39 | \r | |
| 40 | mov edx, [esp + 4] ; edx = JumpBuffer\r | |
| 41 | mov edx, [edx + 24] ; edx = target SSP\r | |
| 42 | READSSP_EAX\r | |
| 43 | sub edx, eax ; edx = delta\r | |
| 44 | mov eax, edx ; eax = delta\r | |
| 45 | \r | |
| 46 | shr eax, 2 ; eax = delta/sizeof(UINT32)\r | |
| 47 | INCSSP_EAX\r | |
| 48 | \r | |
| 49 | CetDone:\r | |
| 50 | \r | |
| f493cf81 JJ |
51 | pop eax ; skip return address\r |
| 52 | pop edx ; edx <- JumpBuffer\r | |
| 53 | pop eax ; eax <- Value\r | |
| 54 | mov ebx, [edx]\r | |
| 55 | mov esi, [edx + 4]\r | |
| 56 | mov edi, [edx + 8]\r | |
| 57 | mov ebp, [edx + 12]\r | |
| 58 | mov esp, [edx + 16]\r | |
| 59 | jmp dword [edx + 20] ; restore "eip"\r | |
| 60 | \r |