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|
;------------------------------------------------------------------------------
;
; Copyright (c) 2010 - 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:
;
; AsmFuncs.nasm
;
; Abstract:
;
; Debug interrupt handle functions.
;
;------------------------------------------------------------------------------
#include "DebugException.h"
;
; InterruptProcess()
;
extern ASM_PFX(InterruptProcess)
global ASM_PFX(Exception0Handle)
global ASM_PFX(TimerInterruptHandle)
global ASM_PFX(ExceptionStubHeaderSize)
%macro AGENT_HANDLER_SIGNATURE 0
db 0x41, 0x47, 0x54, 0x48 ; SIGNATURE_32('A','G','T','H')
%endmacro
SECTION .data
ASM_PFX(ExceptionStubHeaderSize): DD Exception1Handle - ASM_PFX(Exception0Handle)
CommonEntryAddr: DD CommonEntry
SECTION .text
AGENT_HANDLER_SIGNATURE
ASM_PFX(Exception0Handle):
cli
push eax
mov eax, 0
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception1Handle:
cli
push eax
mov eax, 1
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception2Handle:
cli
push eax
mov eax, 2
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception3Handle:
cli
push eax
mov eax, 3
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception4Handle:
cli
push eax
mov eax, 4
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception5Handle:
cli
push eax
mov eax, 5
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception6Handle:
cli
push eax
mov eax, 6
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception7Handle:
cli
push eax
mov eax, 7
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception8Handle:
cli
push eax
mov eax, 8
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception9Handle:
cli
push eax
mov eax, 9
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception10Handle:
cli
push eax
mov eax, 10
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception11Handle:
cli
push eax
mov eax, 11
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception12Handle:
cli
push eax
mov eax, 12
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception13Handle:
cli
push eax
mov eax, 13
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception14Handle:
cli
push eax
mov eax, 14
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception15Handle:
cli
push eax
mov eax, 15
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception16Handle:
cli
push eax
mov eax, 16
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception17Handle:
cli
push eax
mov eax, 17
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception18Handle:
cli
push eax
mov eax, 18
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
Exception19Handle:
cli
push eax
mov eax, 19
jmp dword [CommonEntryAddr]
AGENT_HANDLER_SIGNATURE
ASM_PFX(TimerInterruptHandle):
cli
push eax
mov eax, 32
jmp dword [CommonEntryAddr]
CommonEntry:
;
; +---------------------+
; + EFlags +
; +---------------------+
; + CS +
; +---------------------+
; + EIP +
; +---------------------+
; + Error Code +
; +---------------------+
; + EAX / Vector Number +
; +---------------------+
; + EBP +
; +---------------------+ <-- EBP
;
cmp eax, DEBUG_EXCEPT_DOUBLE_FAULT
je NoExtrPush
cmp eax, DEBUG_EXCEPT_INVALID_TSS
je NoExtrPush
cmp eax, DEBUG_EXCEPT_SEG_NOT_PRESENT
je NoExtrPush
cmp eax, DEBUG_EXCEPT_STACK_FAULT
je NoExtrPush
cmp eax, DEBUG_EXCEPT_GP_FAULT
je NoExtrPush
cmp eax, DEBUG_EXCEPT_PAGE_FAULT
je NoExtrPush
cmp eax, DEBUG_EXCEPT_ALIGNMENT_CHECK
je NoExtrPush
push dword [esp]
mov dword [esp + 4], 0
NoExtrPush:
push ebp
mov ebp, esp ; save esp in ebp
;
; Make stack 16-byte alignment to make sure save fxrstor later
;
and esp, 0xfffffff0
sub esp, 12
; store UINT32 Edi, Esi, Ebp, Ebx, Edx, Ecx, Eax;
push dword [ebp + 4] ; original eax
push ebx
push ecx
push edx
mov ebx, eax ; save vector in ebx
mov eax, ebp
add eax, 4 * 6
push eax ; original ESP
push dword [ebp] ; EBP
push esi
push edi
;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
;; insure FXSAVE/FXRSTOR is enabled in CR4...
;; ... while we're at it, make sure DE is also enabled...
mov eax, 1
push ebx ; temporarily save value of ebx on stack
cpuid ; use CPUID to determine if FXSAVE/FXRESTOR and
; DE are supported
pop ebx ; retore value of ebx that was overwritten by CPUID
mov eax, cr4
push eax ; push cr4 firstly
test edx, BIT24 ; Test for FXSAVE/FXRESTOR support
jz .0
or eax, BIT9 ; Set CR4.OSFXSR
.0:
test edx, BIT2 ; Test for Debugging Extensions support
jz .1
or eax, BIT3 ; Set CR4.DE
.1:
mov cr4, eax
mov eax, cr3
push eax
mov eax, cr2
push eax
push 0 ; cr0 will not saved???
mov eax, cr0
push eax
xor ecx, ecx
mov ecx, Ss
push ecx
mov ecx, Cs
push ecx
mov ecx, Ds
push ecx
mov ecx, Es
push ecx
mov ecx, Fs
push ecx
mov ecx, Gs
push ecx
;; EIP
mov ecx, [ebp + 4 * 3] ; EIP
push ecx
;; UINT32 Gdtr[2], Idtr[2];
sub esp, 8
sidt [esp]
sub esp, 8
sgdt [esp]
;; UINT32 Ldtr, Tr;
xor eax, eax
str ax
push eax
sldt ax
push eax
;; EFlags
mov ecx, [ebp + 4 * 5]
push ecx
;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
mov eax, dr7
push eax
;; clear Dr7 while executing debugger itself
xor eax, eax
mov dr7, eax
;; Dr6
mov eax, dr6
push eax
;; insure all status bits in dr6 are clear...
xor eax, eax
mov dr6, eax
mov eax, dr3
push eax
mov eax, dr2
push eax
mov eax, dr1
push eax
mov eax, dr0
push eax
;; Clear Direction Flag
cld
;; FX_SAVE_STATE_IA32 FxSaveState;
sub esp, 512
mov edi, esp
;; Clear the buffer
xor eax, eax
mov ecx, 128 ;= 512 / 4
rep stosd
mov edi, esp
test edx, BIT24 ; Test for FXSAVE/FXRESTOR support.
; edx still contains result from CPUID above
jz .2
db 0xf, 0xae, 00000111y ;fxsave [edi]
.2:
;; save the exception data
push dword [ebp + 8]
; call the C interrupt process function
push esp ; Structure
push ebx ; vector
call ASM_PFX(InterruptProcess)
add esp, 8
; skip the exception data
add esp, 4
;; FX_SAVE_STATE_IA32 FxSaveState;
mov esi, esp
mov eax, 1
cpuid ; use CPUID to determine if FXSAVE/FXRESTOR are supported
test edx, BIT24 ; Test for FXSAVE/FXRESTOR support
jz .3
db 0xf, 0xae, 00001110y ; fxrstor [esi]
.3:
add esp, 512
;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
pop eax
mov dr0, eax
pop eax
mov dr1, eax
pop eax
mov dr2, eax
pop eax
mov dr3, eax
;; skip restore of dr6. We cleared dr6 during the context save.
add esp, 4
pop eax
mov dr7, eax
;; set EFlags
pop dword [ebp + 4 * 5] ; set EFLAGS in stack
;; UINT32 Ldtr, Tr;
;; UINT32 Gdtr[2], Idtr[2];
;; Best not let anyone mess with these particular registers...
add esp, 24
;; UINT32 Eip;
pop dword [ebp + 4 * 3] ; set EIP in stack
;; UINT32 Gs, Fs, Es, Ds, Cs, Ss;
;; NOTE - modified segment registers could hang the debugger... We
;; could attempt to insulate ourselves against this possibility,
;; but that poses risks as well.
;;
pop gs
pop fs
pop es
pop ds
pop dword [ebp + 4 * 4] ; set CS in stack
pop ss
;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
pop eax
mov cr0, eax
add esp, 4 ; skip for Cr1
pop eax
mov cr2, eax
pop eax
mov cr3, eax
pop eax
mov cr4, eax
;; restore general register
pop edi
pop esi
pop dword [ebp] ; save updated ebp
pop dword [ebp + 4] ; save updated esp
pop edx
pop ecx
pop ebx
pop eax
mov esp, ebp
pop ebp ; restore ebp maybe updated
pop esp ; restore esp maybe updated
sub esp, 4 * 3 ; restore interupt pushced stack
iretd
|