Welcome to the BeaEngine Sweet Home - x86 x86-64 disassembler library - (IA-32 & Intel64)

Examples - Tutorial

Each example you can see here is using one feature of the disassemble library. At first, you can see how to use the library in the simplest manner (to retrieve a simple instructions list). Then, you can see how to use specific options to make special tasks like data-flow analysis or control-flow analysis. You can download all these examples HERE

1- How to decode 100 lines of code ?(basic example)

BeaEngine does not need special initialization. The Disasm function do it for you. The only task you have to perform is setting to zero the _Disasm structure and filling the field MyDisasm.EIP.

This small program desassemble 100 lines of its own code since the virtual address 0x401000.

#include <windows.h>
#include <stdio.h>
#include "BeaEngine.h"

int main(void)
{
	/* ============================= Init datas */
	DISASM MyDisasm;
	int false = 0, true = 1;
	int len, i = 0;
	_Bool Error = false;

	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));

	/* ============================= Init EIP */
	MyDisasm.EIP = 0x401000;

	/* ============================= Loop for Disasm */
	while ((!Error) && (i<100)){
		len = Disasm(&MyDisasm);
		if (len != UNKNOWN_OPCODE) {
			(void) puts(MyDisasm.CompleteInstr);
			MyDisasm.EIP = MyDisasm.EIP + len;
            	i++;
		}
		else {
			Error = true;
		}
	};
	return 0;
}

2- How to decode a limited block of bytes ? (SecurityBlock)

It is possible to ask to BeaEngine to decode a limited block of bytes. This small program decodes instructions of its own code located between 2 virtual addresses (0x401000 and 0x401020, arbitrary choice). That means BeaEngine won't read any bytes outside these limits even if it tries to decode an instruction starting just before the upper bound. To realize this restriction, BeaEngine uses the field MyDisasm.SecurityBlock that contains the number of bytes we want to read. By default, an intel instruction never exceed 15 bytes. Thus, only SecurityBlock values below this limit are used. In all cases, BeaEngine stops decoding an instruction if it exceeds 15 bytes.

#include <windows.h>
#include <stdio.h>
#include "BeaEngine.h"

int main(void)
{
	/* ============================= Init datas */
	DISASM MyDisasm;
	int false = 0, true = 1;
	int len;
	_Bool Error = false;
	int EndCodeSection = 0x401020;

	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));

	/* ============================= Init EIP */
	MyDisasm.EIP = 0x401000;

	/* ============================= Loop for Disasm */
	while (!Error){
		/* ============================= Fix SecurityBlock */
		MyDisasm.SecurityBlock = EndCodeSection - MyDisasm.EIP;

		len = Disasm(&MyDisasm);
		if (len == OUT_OF_BLOCK) {
			(void) printf("disasm engine is not allowed to read more memory \n");
			Error = true;
		}
		else if (len == UNKNOWN_OPCODE) {
			(void) printf("unknown opcode");
			Error = true;
		}
		else {
			(void) puts(MyDisasm.CompleteInstr);
			MyDisasm.EIP = MyDisasm.EIP + len;
			if (MyDisasm.EIP >= EndCodeSection) {
				(void) printf("End of buffer reached ! \n");
				Error = true;
			}
		}
	};
	return 0;
}

3- How to decode bytes in an allocated buffer while keeping original virtual addresses ?

This time, we are in a real and usual situation. We want to decode bytes copied in an allocated buffer. However, you want to see original virtual addresses. The following program allocates a buffer with the function malloc , copies in it 100 bytes from the address &main and decodes the buffer :

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include "BeaEngine.h"

/* ============================= Init datas */
DISASM MyDisasm;
int len;
_Bool Error = 0;
void *pBuffer;
int  (*pSourceCode) (void); 	/* function pointer */

/* ================================================================================= */
/*															*/
/*		Disassemble code in the specified buffer using the correct VA					*/
/*															*/
/*==================================================================================*/

void DisassembleCode(char *StartCodeSection, char *EndCodeSection, int (*Virtual_Address)(void))
{

	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));

	/* ============================= Init EIP */
	MyDisasm.EIP = (int) StartCodeSection;
	/* ============================= Init VirtualAddr */
	MyDisasm.VirtualAddr = (long long) Virtual_Address;

	/* ============================= set IA-32 architecture */
	MyDisasm.Archi = 0;
	/* ============================= Loop for Disasm */
	while ( !Error){
		/* ============================= Fix SecurityBlock */
		MyDisasm.SecurityBlock = (int) EndCodeSection - MyDisasm.EIP;

		len = Disasm(&MyDisasm);
		if (len == OUT_OF_BLOCK) {
			(void) printf("disasm engine is not allowed to read more memory \n");
			Error = 1;
		}
		else if (len == UNKNOWN_OPCODE) {
			(void) printf("unknown opcode");
			Error = 1;
		}
		else {
            (void) printf("%.8X %s\n",(int) MyDisasm.VirtualAddr, &MyDisasm.CompleteInstr);
			MyDisasm.EIP = MyDisasm.EIP + len;
			MyDisasm.VirtualAddr = MyDisasm.VirtualAddr + len;
			if (MyDisasm.EIP >= (int) EndCodeSection) {
				(void) printf("End of buffer reached ! \n");
				Error = 1;
			}
		}
	};
	return;
}

/* ================================================================================= */
/*														*/
/*						MAIN		*/
/*														*/
/*==================================================================================*/
int main(void)
{
	pSourceCode =  &main;

	pBuffer = malloc(100);
	/* ============================= Let's NOP the buffer */
	(void) memset (pBuffer, 0x90, 100);

	/* ============================= Copy 100 bytes in it */
	(void) memcpy (pBuffer,(void*)(int) pSourceCode, 100);

	/* ============================= Disassemble code located in that buffer */
	DisassembleCode (pBuffer, (char*) pBuffer + 100, pSourceCode);
	return 0;
}

4- How to use nasm syntax with prefixed numbers ?

BeaEngine is able to use a set of syntaxes : masm, nasm, GoAsm, GNU Assembler. You can display numbers under two formats : suffixed numbers and prefixed numbers. You can display or not the segment registers used in memory addressing. You can even use a tabulation between mnemonic and first operand.

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include "BeaEngine.h"

/* ============================= Init datas */
DISASM MyDisasm;
int len;
_Bool Error = 0;
void *pBuffer;
int  (*pSourceCode) (void); 	/* function pointer */

/* DisassembleCode function is documented in previous examples */

int main(void)
{

	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));

	pSourceCode =  &main;
	pBuffer = malloc(100);
	/* ============================= Let's NOP the buffer */
	(void) memset (pBuffer, 0x90, 100);
	/* ============================= Copy 100 bytes in it */
	(void) memcpy (pBuffer,(void*)(int) pSourceCode, 100);


	/* ============================= Select Display Option */
	MyDisasm.Options = Tabulation + NasmSyntax + PrefixedNumeral + ShowSegmentRegs;
	/* ============================= Disassemble code located in that buffer */
	DisassembleCode (pBuffer, (char*) pBuffer + 100, pSourceCode);


	return 0;
}

5- How to use the library with Python ?

BeaEngine can be used under Python thanks to the ctypes library.

from BeaEnginePython import *

Instruction = DISASM()

# ====================================== Open File2Disasm.exe
try:
    FileObject = open('File2Disasm.exe','rb')
except IOError:
    print "can't find specified file"
else:
    FileObject.seek(0,0)
    Buffer= FileObject.read()
    FileObject.close()

    # ====================================== Create a ctypes buffer
    Target = create_string_buffer(Buffer,len(Buffer))

    # ====================================== init structure
    Instruction.EIP = addressof(Target) + 0x200	# Jump on the ".text" section with RawOffset = 0x200
    Instruction.VirtualAddr = 0x401000
    Instruction.Options = Tabulation + NasmSyntax + SuffixedNumeral  + ShowSegmentRegs		#define syntax

    # ====================================== Disasm 20 instructions

    for i in range(20):
        InstrLength = Disasm(addressof(Instruction))
        print hex(Instruction.VirtualAddr),"   ",Instruction.CompleteInstr
        if InstrLength == -1:
            Instruction.EIP = Instruction.EIP + 1
            Instruction.VirtualAddr = Instruction.VirtualAddr + 1
        else:
            Instruction.EIP = Instruction.EIP + InstrLength 
            Instruction.VirtualAddr= Instruction.VirtualAddr+ InstrLength 


6- How to retrieve only instructions that modify the register eax ?

This is the first example of how to realize a data-flow analysis with BeaEngine. By using MyDisasm.Argument1.AccessMode and MyDisasm.Argument1.ArgType , you can determine for example if the register eax is modified or not by the analyzed instruction. AccessMode allows us to know if the argument is written or only read. ArgType allows us to know if the register is eax. We don't forget that some instructions can modify registers implicitly. We can control that by looking at the field MyDisasm.Instruction.ImplicitModifiedRegs .

#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include "BeaEngine.h"
/* ============================= Init datas */
DISASM MyDisasm;
int len;
_Bool Error = 0;
void *pBuffer;
int  (*pSourceCode) (void); 	/* function pointer */

/* ================================================================================= */
/*																*/
/*						Disassemble code in the specified buffer using the correct VA			*/
/*																*/
/*==================================================================================*/

void DisassembleCode(char *StartCodeSection, char *EndCodeSection, int (*Virtual_Address)(void))
{

	Error = 0;

	/* ============================= Init EIP */
	MyDisasm.EIP = (int) StartCodeSection;
	/* ============================= Init VirtualAddr */
	MyDisasm.VirtualAddr = (long long) Virtual_Address;

	/* ============================= set IA-32 architecture */
	MyDisasm.Archi = 0;
	/* ============================= Loop for Disasm */
	while ( !Error){
		/* ============================= Fix SecurityBlock */
		MyDisasm.SecurityBlock = (long) EndCodeSection - MyDisasm.EIP;

		len = Disasm(&MyDisasm);
		if (len == OUT_OF_BLOCK) {
			(void) printf("disasm engine is not allowed to read more memory \n");
			Error = 1;
		}
		else if (len == UNKNOWN_OPCODE) {
			(void) printf("unknown opcode");
			Error = 1;
		}
		else {
			/* ============================= Make a filter on Instruction */
			if ((MyDisasm.Argument1.AccessMode == WRITE)
				&& (MyDisasm.Argument1.ArgType & GENERAL_REG)
				&& (MyDisasm.Argument1.ArgType & REG0))  {
					(void) printf("%.8X %s\n",(int) MyDisasm.VirtualAddr, &MyDisasm.CompleteInstr);
			}
			else if ((MyDisasm.Argument2.AccessMode == WRITE)
                    		&& (MyDisasm.Argument2.ArgType & GENERAL_REG)
                    		&& (MyDisasm.Argument2.ArgType & REG0))  {
                        		(void) printf("%.8X %s\n",(int) MyDisasm.VirtualAddr, &MyDisasm.CompleteInstr);
			}
			else if (MyDisasm.Instruction.ImplicitModifiedRegs & REG0) {
				(void) printf("%.8X %s\n",(int) MyDisasm.VirtualAddr, &MyDisasm.CompleteInstr);
		}
			MyDisasm.EIP = MyDisasm.EIP + len;
			MyDisasm.VirtualAddr = MyDisasm.VirtualAddr + len;
			if (MyDisasm.EIP >= (long) EndCodeSection) {
				(void) printf("End of buffer reached ! \n");
				Error = 1;
			}
		}
	};
	return;
}
/* ================================================================================= */
/*														*/
/*												MAIN		*/
/*														*/
/*==================================================================================*/
int main(void)
{

	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));


	pSourceCode =  &main;
	pBuffer = malloc(0x600);
	/* ============================= Let's NOP the buffer */
	(void) memset (pBuffer, 0x90, 0x600);
	/* ============================= Copy 100 bytes in it */
	(void) memcpy (pBuffer,(void*)(int) pSourceCode, 0x600);

	(void) printf("******************************************************* \n");
	(void) printf("Display only Instructions modifying EAX. \n");
	(void) printf("******************************************************* \n");

	/* ============================= Select Display Option */
	MyDisasm.Options = Tabulation + MasmSyntax;
	/* ============================= Disassemble code located in that buffer */
	DisassembleCode (pBuffer, (char*) pBuffer + 0x600, pSourceCode);

	return 0;
}

7- How to decode instructions and 'follow' unconditional branch instructions ?

In some cases, unconditional jumps are used in obfuscation mechanisms. This program shows how to eliminate these naugthy jumps by "following" them. To realize that task, we have to use the fields MyDisasm.Instruction.BranchType and MyDisasm.Instruction.AddrValue. In the next program, I have coded the function RVA2OFFSET just to convert the virtual address pointed by the unconditional jump in a "real" address that can be used by MyDisasm.EIP.

#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include "BeaEngine.h"
/* ============================= Init datas */
DISASM MyDisasm;
int len,i,FileSize;
_Bool Error = 0;
unsigned char *pBuffer;
int  (*pSourceCode) (void); 	/* function pointer */
FILE *FileHandle;

int RVA2OFFSET(int Address, unsigned char *pBuff);

/* =================================================================================*/
/*														*/
/*						eliminate JUMPS  and reorder instructions  	*/
/*														*/
/*==================================================================================*/

void DisassembleCodeFilter(unsigned char *StartCodeSection, unsigned char *EndCodeSection, int (Virtual_Address))
{
	Error = 0;
	MyDisasm.EIP = (int) StartCodeSection;
	MyDisasm.VirtualAddr = (long long) Virtual_Address;
	MyDisasm.Archi = 0;

	/* ============================= Loop for Disasm */
	while (!Error){
		MyDisasm.SecurityBlock = (int) EndCodeSection - MyDisasm.EIP;
		len = Disasm(&MyDisasm);
		if ((len != OUT_OF_BLOCK) && (len != UNKNOWN_OPCODE)) {
			if ((MyDisasm.Instruction.BranchType == JmpType) && (MyDisasm.Instruction.AddrValue != 0)) {
			    MyDisasm.EIP = RVA2OFFSET((int) MyDisasm.Instruction.AddrValue - 0x400000,pBuffer);
			    MyDisasm.VirtualAddr = MyDisasm.Instruction.AddrValue;
			}
			else {
                      (void) printf("%.8X %s\n",(int) MyDisasm.VirtualAddr, &MyDisasm.CompleteInstr);
			    MyDisasm.EIP = MyDisasm.EIP+len;
                	    MyDisasm.VirtualAddr = MyDisasm.VirtualAddr+len;
			}
            	if (MyDisasm.EIP >= (long) EndCodeSection)  {
				Error = 1;
            	}
		}
		else {
			Error = 1;
		}
	}
	return;
}
/* =================================================================================*/
/*														*/
/*	        Convert Relative Virtual Address to offset in the file                */
/*          works fine even in naughty binaries							*/
/*			BeatriX manufacture :)								*/
/*														*/
/*==================================================================================*/

int RVA2OFFSET(int RVA, unsigned char *pBuff)
{
int RawSize, VirtualBorneInf, RawBorneInf, SectionHeader;
int OffsetNtHeaders,OffsetSectionHeaders, NumberOfSections, SizeOfOptionalHeaders, VirtualAddress;

OffsetNtHeaders = (int) *((int*) (pBuff + 0x3c));
NumberOfSections = (int) *((unsigned short*) (pBuff + OffsetNtHeaders + 6));
SizeOfOptionalHeaders = (int) *((unsigned short*) (pBuff + OffsetNtHeaders + 0x14));
OffsetSectionHeaders = OffsetNtHeaders + SizeOfOptionalHeaders + 0x18;
VirtualBorneInf = 0;
RawBorneInf = 0;
VirtualAddress = 0;
SectionHeader = 0;
while (VirtualAddress <= RVA) {
    if (VirtualAddress != 0) {
        VirtualBorneInf = VirtualAddress;
        RawSize = (int) *((unsigned int*) (pBuff + OffsetSectionHeaders + 0x10));
        RawBorneInf = (int) *((unsigned int*) (pBuff + OffsetSectionHeaders + 0x14));
    }
    VirtualAddress = (int) *((unsigned int*) (pBuff + OffsetSectionHeaders + SectionHeader*0x28 + 0x0C));
    SectionHeader ++;
}
if ((RVA-VirtualBorneInf)>RawSize) return -1;
RawBorneInf = RawBorneInf >> 8;
if (RawBorneInf & 1) RawBorneInf--;
RawBorneInf = RawBorneInf << 8;
return RVA - VirtualBorneInf + RawBorneInf + (int) pBuff;
}
/* =================================================================================*/
/*														*/
/*												MAIN		*/
/*														*/
/*==================================================================================*/
int main(void)
{

	FileHandle = fopen("msgbox.exe", "rb");
	(void)fseek(FileHandle,0,SEEK_END);
	FileSize = ftell(FileHandle);
	(void)rewind(FileHandle);
	pBuffer = malloc(FileSize);

	(void)fread(pBuffer,1,FileSize, FileHandle);
	(void)fclose(FileHandle);
	/* ============================= Init the Disasm structure (important !)*/
	(void) memset (&MyDisasm, 0, sizeof(DISASM));

	(void) printf("******************************************************* \n");
	(void) printf("Disassemble code by following jumps\n");
	(void) printf("******************************************************* \n");

	DisassembleCodeFilter ((unsigned char*) pBuffer + 0x400, (unsigned char*) pBuffer + 0x430, 0x401000);
	return 0;
}

8- How to decode instructions on a 64 bits target ?

BeaEngine is compiled here for windows for 32 bits and 64 bits architectures. But, in these two cases, BeaEngine is able to decode 32 bits or 64 bits targets.

	/* =================== Define 64 bits architecture =================== */
	MyDisasm.Archi = 64;

9- How to use BeaEngine with masm32, nasm, fasm ou GoAsm ?

BeaEngine is distributed with headers for nasm, GoAsm, fasm , masm.

Using BeaEngine with masm32

.386
.MODEL flat,stdcall
option casemap:none
.mmx

include \masm32\include\kernel32.inc
include \masm32\include\windows.inc
includelib \masm32\lib\kernel32.lib
include BeaEngineMasm.inc

puts PROTO:DWORD

.data

    MyDisasm        _Disasm         <>
    szoutofblock    BYTE            "Security alert. Disasm tries to read unreadable memory",0
    i               DWORD           100
    
.code

start:

    ; *********************** Init EIP
    mov eax, start
    mov MyDisasm.EIP, eax

    ; *********************** Just for fun : init VirtualAddr with funky value :)
    mov eax, 0bea2008h
    movd mm0, eax
    movq MyDisasm.VirtualAddr, mm0

    ; *********************** loop for disasm
    MakeDisasm:
        push offset MyDisasm
        call Disasm
        .if (eax == OUT_OF_BLOCK)
            push offset szoutofblock
            call puts
            add esp, 4
            push 0
            call ExitProcess
        .elseif (eax == UNKNOWN_OPCODE)
            push offset MyDisasm.CompleteInstr
            call puts                           
            add esp, 4
            push 0
            call ExitProcess
        .endif
        add MyDisasm.EIP, eax
        push offset MyDisasm.CompleteInstr
        call puts                           
        add esp, 4
        dec i
        jne MakeDisasm
    
    push 0
    call ExitProcess
End start                         

Using BeaEngine with nasm

extern _puts@4				; define external symbols
extern _ExitProcess@4
extern _Disasm@4
global start
%include "BeaEngineNasm.inc"

section .data use32

    i       db 100
    
    MyDisasm:
            istruc _Disasm
            iend    

section .text use32

start: 

    ; ***************************** Init EIP
    mov eax, start
    mov [MyDisasm+EIP], eax

    ; ***************************** just for fun : init VirtualAddr with weird address :)
    mov eax, 0xbea2008
    movd mm0, eax
    movq [MyDisasm+VirtualAddr], mm0
    
    ; ***************************** loop for disasm
MakeDisasm:
    push MyDisasm
    call _Disasm@4
    cmp eax, UNKNOWN_OPCODE
    je IncreaseEIP
        add [MyDisasm+EIP], eax
        jmp DisplayInstruction
    
    IncreaseEIP:
        inc dword [MyDisasm+EIP]
    
    DisplayInstruction:
        push MyDisasm+CompleteInstr
        call _puts@4
        add esp, 4
        dec byte [i]
        jne MakeDisasm
    push 0
    call _ExitProcess@4



Using BeaEngine with fasm

format MS COFF

; ************************************** Define "prototype"

extrn '_puts@4' as puts:dword
extrn '_Disasm@4' as Disasm:dword
extrn '_ExitProcess@4' as ExitProcess:dword

; ************************************** includes
include '\fasm\INCLUDE\win32ax.inc'     ; <--- extended headers to enable macroinstruction .if .elseif .end
include 'BeaEngineFasm.inc'


section '.data' data readable writeable


    MyDisasm       _Disasm       <>
    i               db            100
    szoutofblock    db            "Security alert. Disasm tries to read unreadable memory",0


section '.text' code readable executable

 public start

 start:

    ; *********************** Init EIP
    mov eax, start
    mov [MyDisasm.EIP], eax
   
    ; *********************** loop for disasm
    MakeDisasm:
        push MyDisasm
        call Disasm
        .if eax = OUT_OF_BLOCK
            push szoutofblock
            call puts
            add esp, 4
            push 0
            call ExitProcess
        .elseif eax = UNKNOWN_OPCODE
            inc [MyDisasm.EIP]
        .else
            add [MyDisasm.EIP], eax
        .endif
        push MyDisasm.CompleteInstr
        call puts                           
        add esp, 4
        dec byte [i]
        jne MakeDisasm
    push 0
    call ExitProcess





Using BeaEngine with GoAsm

#include BeaEngineGoAsm.inc
Disasm = BeaEngine.lib:Disasm

.data
    
    MyDisasm       _Disasm      <>
    szoutofblock    db           "Security alert. Disasm tries to read unreadable memory",0
    i               db            100
.code

start:

    ; *********************** Init EIP
    mov eax, offset start
    mov [MyDisasm.EIP], eax

    ; *********************** loop for disasm
MakeDisasm:
    push offset MyDisasm
    call Disasm
    cmp eax, OUT_OF_BLOCK
    jne >
        push offset szoutofblock
        call puts
        add esp, 4
        push 0
        call ExitProcess
    :
    cmp eax, UNKNOWN_OPCODE
    jne >
        inc d[MyDisasm.EIP]
        jmp Display
    :
        add [MyDisasm.EIP], eax
Display:        
    push offset MyDisasm.CompleteInstr
    call puts                           
    add esp, 4
    dec b[i]
    jne MakeDisasm
    push 0
    call ExitProcess

10- How to use BeaEngine with masm64 ou GoAsm64 ?

Using BeaEngine with masm64

include ..\..\HEADERS\BeaEngineMasm.inc

extrn puts:PROC
extrn ExitProcess: PROC


.data

    MyDisasm        _Disasm         <>
    szoutofblock    BYTE            "Security alert. Disasm tries to read unreadable memory",0
    i               DWORD           100


.code

main proc

    ; *********************** Init EIP
    mov rax, main
    mov MyDisasm.EIP, rax

    ; *********************** Init Architecture
    mov MyDisasm.Archi, 64

    ; *********************** loop for disasm
    MakeDisasm:
        mov rcx, offset MyDisasm
        call Disasm
        cmp eax, OUT_OF_BLOCK
        jne @F
            mov rcx, offset szoutofblock
            sub rsp, 20h
            call puts
            add rsp, 20h
            mov rcx, 0
            call ExitProcess
        @@:
        cmp eax, UNKNOWN_OPCODE
        jne @F
            inc MyDisasm.EIP
            jmp Display
        @@:
            add MyDisasm.EIP, rax
    Display:
        mov rcx, offset MyDisasm.CompleteInstr
        sub rsp, 20h
        call puts                           
        add rsp, 20h
        dec i
        jne MakeDisasm
    
    mov rcx, 0
    call ExitProcess
main endp

end

Using BeaEngine with GoAsm64

#include BeaEngineGoAsm.inc
Disasm = BeaEngine64.lib:Disasm

.data
    
    MyDisasm       _Disasm      <>
    szoutofblock    db           "Security alert. Disasm tries to read unreadable memory",0
    i               db            100
.code

start:

    ; *********************** Init EIP
    mov rax, offset start
    mov q [MyDisasm.EIP], rax

    ; *********************** Init Architecture
    mov d [MyDisasm.Archi], 64

    ; *********************** loop for disasm
MakeDisasm:
    mov rcx, offset MyDisasm
    call Disasm
    cmp rax, OUT_OF_BLOCK
    jne >
        mov rcx, offset szoutofblock
        sub rsp, 20h
        call puts
        add rsp, 20h
        mov rcx, 0
        call ExitProcess
    :
    cmp rax, UNKNOWN_OPCODE
    jne >
        inc q[MyDisasm.EIP]
        jmp Display
    :
        add q[MyDisasm.EIP], rax
Display:        
    mov rcx, offset MyDisasm.CompleteInstr
    sub rsp, 20h
    call puts                           
    add rsp, 20h
    dec b[i]
    jne MakeDisasm
    mov rcx, 0
    call ExitProcess





11- How to use BeaEngine with WinDev (by Vincent Roy) ?

Here is an example coded by a friend, Vincent Roy, specialized in WinDev language.

// Creation du Header beaEngine pour Windev

// Creation des constantes
CONSTANT
	NoTabulation 	= 0x0
	Tabulation 	= 0x1
	MasmSyntax 	= 0x000
	GoAsmSyntax 	= 0x100
	NasmSyntax 	= 0x200
      ATSyntax = 0x400
	PrefixedNumeral = 0x10000
	SuffixedNumeral = 0x00000
      ShowSegmentRegs = 0x1000000
	UNKNOWN_OPCODE  = -1
FIN

// Creation des structures
// Rajout Code Vince pour la nouvelle DLL de beatrix2004
REX_Struct est une structure
	W_ est un entier sur 1 octets
	R_ est un entier sur 1 octets
	X_ est un entier sur 1 octets
	B_ est un entier sur 1 octets
	state est un entier sur 1 octets
FIN

PREFIXINFO est une structure
	Number est un entier
	NbUndefined est un entier
	LockPrefix est un entier sur 1 octets
	OperandSize est un entier sur 1 octets
	AddressSize est un entier sur 1 octets
	RepnePrefix est un entier sur 1 octets
	RepPrefix est un entier sur 1 octets
	FSPrefix est un entier sur 1 octets
	SSPrefix est un entier sur 1 octets
	GSPrefix est un entier sur 1 octets
	ESPrefix est un entier sur 1 octets
	CSPrefix est un entier sur 1 octets
	DSPrefix est un entier sur 1 octets
	REX est un REX_Struct
FIN


EFLStruct est une structure
	nOF_ est un entier sur 1 octet
	nSF_ est un entier sur 1 octet
	nZF_ est un entier sur 1 octet
	nAF_ est un entier sur 1 octet
	nPF_ est un entier sur 1 octet
	nCF_ est un entier sur 1 octet
	nTF_ est un entier sur 1 octet
	nIF_ est un entier sur 1 octet
	nDF_ est un entier sur 1 octet
	nNT_ est un entier sur 1 octet
	nRF_ est un entier sur 1 octet
	nAlignment est un entier sur 1 octet
FIN

MEMORYTYPE est une structure
	nBaseRegister est un entier sur 4 octets
	nIndexRegister est un entier sur 4 octets
	nScale est un entier sur 4 octets
	nDisplacement est un entier sur 8 octets
FIN

INSTRTYPE est une structure
	nCategory est un entier sur 4 octets
	nOpcode est un entier sur 4 octets
	Mnemonic est une chaîne fixe sur 16
	nBranchType est un entier sur 4 octets
	stFlags est un EFLStruct
	nAddrValue est un entier sur 8 octets
	nImmediat est un entier sur 8 octets
	nImplicitModifiedRegs est un entier sur 4 octets
FIN

ARGTYPE est une structure
	ArgMnemonic est une chaîne fixe sur 32
	nArgType est un entier sur 4 octets
	nArgSize est un entier sur 4 octets
	nAccessMode est un entier sur 4 octets
	stMemory est un MEMORYTYPE
      nSegmentReg est un entier sur 4 octets
FIN

_Disasm est une structure
	EIP est un entier sans signe sur 8 octets
	VirtualAddr est un entier sans signe sur 8 octets
	SecurityBlock est un entier sur 4 octets
	CompleteInstr est une chaîne fixe sur 64
	Archi est un entier sur 4 octets
	nOptions est un entier sur 4 octets
	stInstruction est un INSTRTYPE
	stArgument1 est un ARGTYPE
	stArgument2 est un ARGTYPE
	stArgument3 est un ARGTYPE
	Prefix est un PREFIXINFO
FIN

// Creation d un objet Disasm (equivalent à struct _Disasm MonDisasm; en C)
Disasm est un _Disasm

// Mise à jour des Options (optionnel)
Disasm:nOptions = Tabulation+NasmSyntax+PrefixedNumeral

// Chargement de la dll BeaEngine (ChargeDLL est une fonction windev)
HandleDLL est un entier = ChargeDLL ("C:\BeaEngine.dll")
si HandleDLL = -1 ALORS
	Erreur ("chargement impossible de la DLL.")
	RETOUR
FIN

// Initialisation des Datas
Disasm:EIP		= 0x401000
Disasm:VirtualAddr 	= 0x0
Disasm:Archi 		= 0

len 	est un entier 	= 0
myError est un entier 	= 0
i 	est un entier 	= 1


TANTQUE (i<=100 ET myError=0)

	// Appel de la fonction exportée Disam (AppelDLL32 est une fonction windev)
	len = AppelDLL32("C:\BeaEngine.dll","Disasm",&Disasm)
	SI (len=UNKNOWN_OPCODE) ALORS
		myError = 1
	SINON
		// Liste les instructions (Trace est une fonction windev. Elle affiche une fenetre de "Trace" de couleur jaune)
		Trace (Disasm:CompleteInstr)
		Disasm:EIP += len
		i++
	FIN
FIN

dechargeDLL (HandleDLL)

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