MASM code to execute shellcode from a file

shellcodeExec.asm

.386
.model flat, stdcall
OPTION  CaseMap:None

.stack 6096
ExitProcess PROTO, dwExitCode: DWORD



include \masm32\include\windows.inc
include \masm32\include\user32.inc
include \masm32\include\kernel32.inc
includelib \masm32\lib\user32.lib
includelib\masm32\lib\kernel32.lib


includelib  \masm32\lib\msvcrt.lib



printf PROTO C :VARARG  ; The secret sauce.. a prototype of printf

include \masm32\include\advapi32.inc
includelib \masm32\lib\advapi32.lib

.data
	 shellcodePath9 db 'C:\\Users\\J\\Desktop\\shellcode.bin',0
.code 
shellcode PROC 
			push ebx
			push ecx
			push edx
			push esi
 
			mov esi, offset shellcodePath9
			invoke CreateFile, esi, GENERIC_READ,FILE_SHARE_READ,NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL
			push eax ; handle to a file

			invoke GetFileSize, eax,NULL
			mov ebx,eax ; file size
			pop ecx ; handle to a file
			mov edx,138240 ; FILE_MAP_START = 138240
			invoke CreateFileMapping, ecx,NULL,PAGE_READONLY,0,ebx,NULL
			invoke MapViewOfFile, eax ,FILE_MAP_READ,0, edx ,ebx
			mov ecx, eax 
			push ecx
			invoke VirtualAlloc,0,ebx,MEM_COMMIT, PAGE_EXECUTE_READWRITE
			pop ecx
			; ebx : file size 
			; ecx : old memory location 
			; eax : new memory location to be copied to 
			push ebx
			push ecx
			push eax
			push edx

			mov esi,0
loop9: ; Loop to copy the shellcode bytes manually
			cmp esi,ebx
			je end9
			mov dl,[ecx + esi]
			push ecx
			mov ecx,eax
			mov [ecx + esi], dl
			pop ecx
			inc esi
			jmp loop9
			
end9: 
			pop edx
			pop eax
			pop ecx
			pop ebx
			call eax  ; calling the memory region  

			pop esi 
			pop edx
			pop ecx
			pop ebx
			ret
shellcode ENDP


main PROC
  call shellcode
	INVOKE ExitProcess, 0
main ENDP
END main