#!/usr/bin/python from unicorn import * from unicorn.x86_const import * from capstone import * ESP = 0x2000 PAGE_SIZE = 2 * 1024 * 1024 # mov [esp], DWORD 0x37f # fldcw [esp] # fnop # fnstenv [esp + 8] # pop ecx CODE = "C704247F030000D92C24D9D0D974240859".decode('hex') class SimpleEngine: def __init__(self): self.capmd = Cs(CS_ARCH_X86, CS_MODE_64) def disas_single(self, data): for i in self.capmd.disasm(data, 16): print("\t%s\t%s" % (i.mnemonic, i.op_str)) break disasm = SimpleEngine() def hook_code(uc, addr, size, user_data): mem = uc.mem_read(addr, size) print(" 0x%X:" % (addr)), disasm.disas_single(str(mem)) def mem_reader(addr, size): tmp = mu.mem_read(addr, size) for i in tmp: print(" 0x%x" % i), print("") mu = Uc(UC_ARCH_X86, UC_MODE_64) mu.mem_map(0x0, PAGE_SIZE) mu.mem_write(0x4000, CODE) mu.reg_write(UC_X86_REG_RSP, ESP) mu.hook_add(UC_HOOK_CODE, hook_code) mu.emu_start(0x4000, 0, 0, 5) rsp = mu.reg_read(UC_X86_REG_RSP) print("Value of FPIP: [0x%X]" % (rsp + 10)) mem_reader(rsp + 10, 8) # EXPECTED OUTPUT: # 0x4000: mov dword ptr [rsp], 0x37f # 0x4007: fldcw word ptr [rsp] # 0x400A: fnop # 0x400C: fnstenv dword ptr [rsp + 8] # 0x4010: pop rcx # Value of FPIP: [0x2012] # 0x0 0x0 0xa 0x40 0x0 0x0 0x0 0x0 # WHERE: the value of FPIP should be the address of fnop