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[原创]python310新特性->Structural Pattern Matching在VM虚拟机逆向中的妙用
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发表于: 2023-11-2 16:24
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前言:
这种写法最初是在2022-GoogleCTF-eldar, 国外的DiceGang的hgarrereyn师傅的wp:https://ctf.harrisongreen.me/2022/googlectf/eldar/中首次用到。也是用于解析虚拟机, 不过是用于解析的ELF metadata-driven turing weird machine。
然后后来国内的2022-强网杯中的deeprev又将这个ELF metadata-driven turing weird machine出了一次, 我也用其来写过这个重定位机的解析,确实效果非常好，可以说毫不夸张像魔法一样。
当时就在Todolist中写道, 用Structural Pattern Matching这种新特性去写下正常虚拟机的解析, 肯定属于是轻轻松松。后续工作上的事情就放下了没去完成, 在我的Todolist中吃灰了接近一年，这一年都在被工作推着走，每天就像机器人一样去执行自己头天写的指令，记忆好像也变差了，经常忘事情，年末项目交付了一些了才有时间弄些自己的，创业之路真的很难。
言归正传, 后续在dicectf-2022-breach这道题的wp:https://github.com/reductor/dice-ctf-2022-breach-writeup中，被正式用于了解析常规虚拟机。
直至放到了今日, 才回来写个这个。
其实虚拟机解析之前我在之前已经发过不少:
[原创]对VM逆向的分析(CTF)(比较经典的一个虚拟机逆向题目)
[原创]处理VM的一种特殊方法和思路
[原创]CTF之自动化VM分析
总结来说, 这种方法属于是disassembler的升级版, 远优于之前发的disassembler, 你说它优于decompiler吗? 我无法给出一个肯定答案, 毕竟decompiler属于一种抽象为高级语言的思路。
PEP 634 – Structural Pattern Matching: Specification：介绍 match 语法和支持的模式
PEP 635 – Structural Pattern Matching: Motivation and Rationale：解释语法这么设计的理由
PEP 636 – Structural Pattern Matching: Tutorial：一个教程。介绍概念、语法和语义
match patterns：
匹配一个模式，并绑定到一个name
用来进一步限制匹配模式，如下
给限制条件取别名，使其能够与bind name一起工作
子模式在 match 语法里面是可以灵活组合的。
第一种写法，用逗号分隔：
第二种写法与C语言类似：
第三种写法：
第四种写法：
第五种写法：
使用 Python 自带的基本数据结构，如字符串、数字、布尔值和 None等
Wildcard Pattern 是一种特殊的 capture pattern，它接收任何值，但是不将该值绑定到任何一个变量（其实就是忽略不关心的位置）
这种模式主要匹配常量或者 enum 模块的枚举值：
就是在模式中使用其他变量的值，那么使用的其他变量与 capture 模式的绑定名如何区分呢？用 "." 区分。
目前只能使用带 '.' 的常量。
可以在 match 里使用列表或者元组格式的结果。
不区分 [a, b, c], (a, b, c) 和 a, b, c，它们是等价的，若要明确判断类型则需要 list([a, b, c])
加星号的模式会匹配任意长度的元素，例如 (*, 3, *), 匹配任何含有 3 的列表。
不会迭代整个迭代器，所有的元素以下标和切片的形式访问。
为了效率，key 必须是常量(literals、value patterns)
其实就是 case 后支持使用字典做匹配
Class Patterns 主要实现两个目标：检查对象是某个类的实例、从对象的特定属性中提取数据。
另外一个例子：
namedtuple 例子，也属于是 class pattern：
numbers 的类型指定为 List，元素类型可以是 float 或 int。
可以定义类型别名，类型检查器和程序员都可以识别到这种模式：
Type guards 用于缩小 type union 的范围。
一般这种disassembler都是逐渐去优化的，优化到最后能使用https://docs.pwntools.com/en/stable/asm.html#pwnlib.asm.make_elf_from_assembly
直接装配成一个elf
Ezmachine-disassembler-parsefunc.py
Ezmachine-disassembler-parsefunc.out
拿parsefunc.out的原因是检查parse及指定类型定义是否合理。
Ezmachine-disassembler-version0.py
Ezmachine-disassembler-dumpfunc-version0.out
其实这里拿到的Ezmachine-disassembler-dumpfunc-version0.out，就跟以前我们的disassembler得到的差不多。
拿这个dumpfunc-version0.out的目的，就是为了参考这个去做优化。
Ezmachine-disassembler-out.asm
Mapping patterns: match mapping structures like dictionaries.Sequence patterns: match sequence structures like tuples and lists.
Capture patterns: bind values to names.AS patterns: bind the value of subpatterns to names.OR patterns: match one of several different subpatterns.Wildcard patterns: match anything.Class patterns: match class structures.
Value patterns: match values stored in attributes.
Literal patterns: match literal values.Mapping patterns: match mapping structures like dictionaries.Sequence patterns: match sequence structures like tuples and lists.
Capture patterns: bind values to names.AS patterns: bind the value of subpatterns to names.OR patterns: match one of several different subpatterns.Wildcard patterns: match anything.Class patterns: match class structures.
Value patterns: match values stored in attributes.
Literal patterns: match literal values.def sum_list(numbers):
match numbers:
case []: # 匹配空列表
return 0
case [first, *rest]:# sequence pattern, 由两个capture pattern 组成的 sequence pattern。*rest 匹配剩下的所有元素
return first + sum_list(rest)
def sum_list(numbers):
match numbers:
case []: # 匹配空列表
return 0
case [first, *rest]:# sequence pattern, 由两个capture pattern 组成的 sequence pattern。*rest 匹配剩下的所有元素
return first + sum_list(rest)
def average(*args):
match args:
case [x, y]: # captures the two elements of a sequence
return (x + y) / 2
case [x]: # captures the only element of a sequence
return x
case []:
return 0
case a: # captures the entire sequence
return sum(a) / len(a)
def average(*args):
match args:
case [x, y]: # captures the two elements of a sequence
return (x + y) / 2
case [x]: # captures the only element of a sequence
return x
case []:
return 0
case a: # captures the entire sequence
return sum(a) / len(a)
# 从小到大排序def sort(seq):
match seq:
case [] | [_]: # 匹配空序列[] 或者 非空列表中的任何单个元素[_]
return seq
case [x, y] if x <= y:
return seq
case [x, y]:
return [y, x]
case [x, y, z] if x <= y <= z:
return seq
case [x, y, z] if x >= y >= z:
return [z, y, x]
case [p, *rest]:
a = sort([x for x in rest if x <= p]) # 比p小的去排序
b = sort([x for x in rest if p < x]) # 比p大的去排序
return a + [p] + b
# 从小到大排序def sort(seq):
match seq:
case [] | [_]: # 匹配空序列[] 或者 非空列表中的任何单个元素[_]
return seq
case [x, y] if x <= y:
return seq
case [x, y]:
return [y, x]
case [x, y, z] if x <= y <= z:
return seq
case [x, y, z] if x >= y >= z:
return [z, y, x]
case [p, *rest]:
a = sort([x for x in rest if x <= p]) # 比p小的去排序
b = sort([x for x in rest if p < x]) # 比p大的去排序
return a + [p] + b
In : def as_pattern(obj):
...: match obj:...: case str() as s:
...: print(f'Got str: {s=}')
...: case [0, int() as i]:
...: print(f'Got int: {i=}')
...: case [tuple() as tu]:
...: print(f'Got tuple: {tu=}')
...: case list() | set() | dict() as iterable:
...: print(f'Got iterable: {iterable=}')
...:...:In : as_pattern('sss')
Got str: s='sss'
In : as_pattern([0, 1])
Got int: i=1
In : as_pattern([(1,)])
Got tuple: tu=(1,)
In : as_pattern([1, 2, 3])
Got iterable: iterable=[1, 2, 3]
In : as_pattern({'a': 1})
Got iterable: iterable={'a': 1}
In : def as_pattern(obj):
...: match obj:...: case str() as s:
...: print(f'Got str: {s=}')
...: case [0, int() as i]:
...: print(f'Got int: {i=}')
...: case [tuple() as tu]:
...: print(f'Got tuple: {tu=}')
...: case list() | set() | dict() as iterable:
...: print(f'Got iterable: {iterable=}')
...:...:In : as_pattern('sss')
Got str: s='sss'
In : as_pattern([0, 1])
Got int: i=1
In : as_pattern([(1,)])
Got tuple: tu=(1,)
In : as_pattern([1, 2, 3])
Got iterable: iterable=[1, 2, 3]
In : as_pattern({'a': 1})
Got iterable: iterable={'a': 1}
def simplify_expr(tokens):
match tokens:
case [('('|'[') as l, *expr, (')'|']') as r] if (l+r) in ('()', '[]'):
return simplify_expr(expr)
case [0, ('+'|'-') as op, right]:
return UnaryOp(op, right)
case [(int() | float() as left) | Num(left), '+', (int() | float() as right) | Num(right)]:
return Num(left + right)
case [(int() | float()) as value]:
return Num(value)
def simplify_expr(tokens):
match tokens:
case [('('|'[') as l, *expr, (')'|']') as r] if (l+r) in ('()', '[]'):
return simplify_expr(expr)
case [0, ('+'|'-') as op, right]:
return UnaryOp(op, right)
case [(int() | float() as left) | Num(left), '+', (int() | float() as right) | Num(right)]:
return Num(left + right)
case [(int() | float()) as value]:
return Num(value)
case 401, 403, 404:
print("Some HTTP error")
case 401, 403, 404:
print("Some HTTP error")
case 401:
case 403:
case 404:
print("Some HTTP error")
case 401:
case 403:
case 404:
print("Some HTTP error")
case in 401, 403, 404:
print("Some HTTP error")
case in 401, 403, 404:
print("Some HTTP error")
case ("a"|"b"|"c"):
case ("a"|"b"|"c"):
case ("a"|"b"|"c") as letter:
case ("a"|"b"|"c") as letter:
match number: case 0:
print('zero')
case 1:
print('one')
case 2:
print('two')
match number: case 0:
print('zero')
case 1:
print('one')
case 2:
print('two')
def simplify(expr):
match expr:
case ('+', 0, x): # x + 0
return x
case ('+' | '-', x, 0): # x +- 0
return x
case ('and', True, x): # True and x
return x
case ('and', False, x):
return False
case ('or', False, x):
return x
case ('or', True, x):
return True
case ('not', ('not', x)):
return x
return expr
def simplify(expr):
match expr:
case ('+', 0, x): # x + 0
return x
case ('+' | '-', x, 0): # x +- 0
return x
case ('and', True, x): # True and x
return x
case ('and', False, x):
return False
case ('or', False, x):
return x
case ('or', True, x):
return True
case ('not', ('not', x)):
return x
return expr
def is_closed(sequence):
match sequence:
case [_]: # any sequence with a single element
return True
case [start, *_, end]: # a sequence with at least two elements
return start == end
case _: # anything
return False
def is_closed(sequence):
match sequence:
case [_]: # any sequence with a single element
return True
case [start, *_, end]: # a sequence with at least two elements
return start == end
case _: # anything
return False
In : class Color(Enum):
...: RED = 1
...: GREEN = 2
...: BLUE = 3
...:In : class NewColor:
...: YELLOW = 4
...:In : def constant_value(color):
...: match color:...: case Color.RED:...: print('Red')
...: case NewColor.YELLOW:...: print('Yellow')
...: case new_color:...: print(new_color)
...:In : constant_value(Color.RED) # 匹配第一个case
RedIn : constant_value(NewColor.YELLOW) # 匹配第二个case
YellowIn : constant_value(Color.GREEN) # 匹配第三个case
Color.GREENIn : constant_value(4) # 常量值一样都匹配第二个case
YellowIn : constant_value(10) # 其他常量
10这里注意，因为 case 具有绑定的作用，所以不能直接使用 YELLOW 这种常量，例如下面这样:YELLOW = 4
def constant_value(color):
match color:
case YELLOW:
print('Yellow')
# 这样语法是错误的In : class Color(Enum):
...: RED = 1
...: GREEN = 2
...: BLUE = 3
...:In : class NewColor:
...: YELLOW = 4
...:In : def constant_value(color):
...: match color:...: case Color.RED:...: print('Red')
...: case NewColor.YELLOW:...: print('Yellow')
...: case new_color:...: print(new_color)
...:In : constant_value(Color.RED) # 匹配第一个case
RedIn : constant_value(NewColor.YELLOW) # 匹配第二个case
YellowIn : constant_value(Color.GREEN) # 匹配第三个case
Color.GREENIn : constant_value(4) # 常量值一样都匹配第二个case
YellowIn : constant_value(10) # 其他常量
10这里注意，因为 case 具有绑定的作用，所以不能直接使用 YELLOW 这种常量，例如下面这样:YELLOW = 4
def constant_value(color):
match color:
case YELLOW:
print('Yellow')
# 这样语法是错误的class Codes:
SUCCESS = 200
NOT_FOUND = 404
def handle(retcode):
match retcode:
case Codes.SUCCESS:
print('success')
case Codes.NOT_FOUND:
print('not found')
case _:
print('unknown')
class Codes:
SUCCESS = 200
NOT_FOUND = 404
def handle(retcode):
match retcode:
case Codes.SUCCESS:
print('success')
case Codes.NOT_FOUND:
print('not found')
case _:
print('unknown')
In : def sequence(collection):...: match collection:...: case 1, [x, *others]:
...: print(f"Got 1 and a nested sequence: {x=}, {others=}")
...: case (1, x):
...: print(f"Got 1 and {x}")
...: case [x, y, z]:
...: print(f"{x=}, {y=}, {z=}")
...:In : sequence([1])
In : sequence([1, 2])
Got 1 and 2
In : sequence([1, 2, 3])
x=1, y=2, z=3
In : sequence([1, [2, 3]])
Got 1 and a nested sequence: x=2, others=[3]
In : sequence([1, [2, 3, 4]])
Got 1 and a nested sequence: x=2, others=[3, 4]
In : sequence([2, 3])
In : sequence((1, 2))
Got 1 and 2
In : def sequence(collection):...: match collection:...: case 1, [x, *others]:
...: print(f"Got 1 and a nested sequence: {x=}, {others=}")
...: case (1, x):
...: print(f"Got 1 and {x}")
...: case [x, y, z]:
...: print(f"{x=}, {y=}, {z=}")
...:In : sequence([1])
In : sequence([1, 2])
Got 1 and 2
In : sequence([1, 2, 3])
x=1, y=2, z=3
In : sequence([1, [2, 3]])
Got 1 and a nested sequence: x=2, others=[3]
In : sequence([1, [2, 3, 4]])
Got 1 and a nested sequence: x=2, others=[3, 4]
In : sequence([2, 3])
In : sequence((1, 2))
Got 1 and 2
In : def mapping(config):
...: match config:...: case {'sub': sub_config, **rest}:
...: print(f'Sub: {sub_config}')
...: print(f'OTHERS: {rest}')
...: case {'route': route}:
...: print(f'ROUTE: {route}')
...:In : mapping({})In : mapping({'route': '/auth/login'})
ROUTE: /auth/login
# 匹配有sub键的字典，值绑定到sub_config上，字典其他部分绑定到rest上In : mapping({'route': '/auth/login', 'sub': {'a': 1}})
Sub: {'a': 1}
OTHERS: {'route': '/auth/login'}
In : def mapping(config):
...: match config:...: case {'sub': sub_config, **rest}:
...: print(f'Sub: {sub_config}')
...: print(f'OTHERS: {rest}')
...: case {'route': route}:
...: print(f'ROUTE: {route}')
...:In : mapping({})In : mapping({'route': '/auth/login'})
ROUTE: /auth/login
# 匹配有sub键的字典，值绑定到sub_config上，字典其他部分绑定到rest上In : mapping({'route': '/auth/login', 'sub': {'a': 1}})
Sub: {'a': 1}
OTHERS: {'route': '/auth/login'}
def change_red_to_blue(json_obj):
match json_obj:
case { 'color': ('red' | '#FF0000') }:
json_obj['color'] = 'blue'
case { 'children': children }:
for child in children:
change_red_to_blue(child)
def change_red_to_blue(json_obj):
match json_obj:
case { 'color': ('red' | '#FF0000') }:
json_obj['color'] = 'blue'
case { 'children': children }:
for child in children:
change_red_to_blue(child)
# case 后支持任何对象做匹配。我们先来一个错误的示例:In : class Point:
...: def __init__(self, x, y):
...: self.x = x
...: self.y = y
...:In : def class_pattern(obj):
...: match obj:...: case Point(x, y):...: print(f'Point({x=},{y=})')
...:In : class_pattern(Point(1, 2))
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)Input In [], in <cell line: 1>()
----> 1 class_pattern(Point(1, 2))
Input In [], in class_pattern(obj)
1 def class_pattern(obj):
2 match obj:
----> 3 case Point(x, y):
4 print(f'Point({x=},{y=})')
TypeError: Point() accepts 0 positional sub-patterns (2 given)
# 这是因为对于匹配来说， 位置需要确定 ，所以需要使用位置参数来标识:In : def class_pattern(obj):
...: match obj:...: case Point(x=1, y=2):
...: print(f'match')
...:In : class_pattern(Point(1, 2))
match# 另外一个解决这种自定义类不用位置参数的匹配方案，使用 __match_args__ 返回一个位置参数的数组，# 就像这样:In : class Point:
...: __match_args__ = ('x', 'y')
...:...: def __init__(self, x, y):
...: self.x = x
...: self.y = y
...:# 还有就是用dataclass, 这里的 Point2 使用了标准库的 dataclasses.dataclass 装饰器# 它会提供 __match_args__ 属性，所以可以直接用In : from dataclasses import dataclass
In : @dataclass...: class Point2:
...: x: int
...: y: int
...:In : def class_pattern(obj):
...: match obj:...: case Point(x, y):...: print(f'Point({x=},{y=})')
...: case Point2(x, y):...: print(f'Point2({x=},{y=})')
...:In : class_pattern(Point(1, 2))
Point(x=1,y=2)
In : class_pattern(Point2(1, 2))
Point2(x=1,y=2)
# case 后支持任何对象做匹配。我们先来一个错误的示例:In : class Point:
...: def __init__(self, x, y):
...: self.x = x
...: self.y = y
...:In : def class_pattern(obj):
...: match obj:...: case Point(x, y):...: print(f'Point({x=},{y=})')
...:In : class_pattern(Point(1, 2))
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)Input In [], in <cell line: 1>()
----> 1 class_pattern(Point(1, 2))
Input In [], in class_pattern(obj)
1 def class_pattern(obj):
2 match obj:
----> 3 case Point(x, y):
4 print(f'Point({x=},{y=})')
TypeError: Point() accepts 0 positional sub-patterns (2 given)
# 这是因为对于匹配来说， 位置需要确定 ，所以需要使用位置参数来标识:In : def class_pattern(obj):
...: match obj:...: case Point(x=1, y=2):
...: print(f'match')
...:In : class_pattern(Point(1, 2))
match# 另外一个解决这种自定义类不用位置参数的匹配方案，使用 __match_args__ 返回一个位置参数的数组，# 就像这样:In : class Point:
...: __match_args__ = ('x', 'y')
...:...: def __init__(self, x, y):
...: self.x = x
...: self.y = y
...:# 还有就是用dataclass, 这里的 Point2 使用了标准库的 dataclasses.dataclass 装饰器# 它会提供 __match_args__ 属性，所以可以直接用In : from dataclasses import dataclass
In : @dataclass...: class Point2:
...: x: int
...: y: int
...:In : def class_pattern(obj):
...: match obj:...: case Point(x, y):...: print(f'Point({x=},{y=})')
...: case Point2(x, y):...: print(f'Point2({x=},{y=})')
...:In : class_pattern(Point(1, 2))
Point(x=1,y=2)
In : class_pattern(Point2(1, 2))
Point2(x=1,y=2)
def eval_expr(expr):
"""Evaluate an expression and return the result."""
match expr:
case BinaryOp('+', left, right):
return eval_expr(left) + eval_expr(right)
case BinaryOp('-', left, right):
return eval_expr(left) - eval_expr(right)
case BinaryOp('*', left, right):
return eval_expr(left) * eval_expr(right)
case BinaryOp('/', left, right):
return eval_expr(left) / eval_expr(right)
case UnaryOp('+', arg):
return eval_expr(arg)
case UnaryOp('-', arg):
return -eval_expr(arg)
case VarExpr(name):
raise ValueError(f"Unknown value of: {name}")
case float() | int():
return expr
case _:
raise ValueError(f"Invalid expression value: {repr(expr)}")
def eval_expr(expr):
"""Evaluate an expression and return the result."""
match expr:
case BinaryOp('+', left, right):
return eval_expr(left) + eval_expr(right)
case BinaryOp('-', left, right):
return eval_expr(left) - eval_expr(right)
case BinaryOp('*', left, right):
return eval_expr(left) * eval_expr(right)
case BinaryOp('/', left, right):
return eval_expr(left) / eval_expr(right)
case UnaryOp('+', arg):
return eval_expr(arg)
case UnaryOp('-', arg):
return -eval_expr(arg)
case VarExpr(name):
raise ValueError(f"Unknown value of: {name}")
case float() | int():
return expr
case _:
raise ValueError(f"Invalid expression value: {repr(expr)}")
match media_object: case Image(type="jpg"):
return media_object
case Image(type="png") | Image(type="gif"):
return render_as(media_object, "jpg")
case Video():
raise ValueError("Can't extract frames from video yet")
case other_type:
raise Exception(f"Media type {media_object} can't be handled yet")
match media_object: case Image(type="jpg"):
return media_object
case Image(type="png") | Image(type="gif"):
return render_as(media_object, "jpg")
case Video():
raise ValueError("Can't extract frames from video yet")
case other_type:
raise Exception(f"Media type {media_object} can't be handled yet")
from collections import namedtuple
Mov = namedtuple('mov', ['dst', 'src', 'sz', 'ridx'])
switch op: case Mov(dst, src, 8, ridx):
pass
from collections import namedtuple
Mov = namedtuple('mov', ['dst', 'src', 'sz', 'ridx'])
switch op: case Mov(dst, src, 8, ridx):
pass
def mean(numbers: list[float | int]) -> float:
return sum(numbers) / len(numbers)
def mean(numbers: list[float | int]) -> float:
return sum(numbers) / len(numbers)
from typing import TypeAlias
Card: TypeAlias = tuple[str, str] # ('', '')
Deck: TypeAlias = list[Card] # [('', '')]
from typing import TypeAlias
Card: TypeAlias = tuple[str, str] # ('', '')
Deck: TypeAlias = list[Card] # [('', '')]
| Opcode | Instruction | Notes |
|---|---|---|
| 0 | nop | pc+=1 |
| 1 | mov dst, imm | imm is an 1-byte immediate value |
| 2 | push imm | imm is an 1-byte immediate value |
| 3 | push reg | put (1-byte)reg in stack |
| 4 | pop reg | pop (1-byte) from stack to reg |
| 5 | PrintStr | print str by edx: 0:'right', 1:'wrong', 3:'plz input:', 4:'hacker’ |
| 6 | add reg1, reg2 | reg1 += reg2 |
| 7 | sub reg1, reg2 | reg1 -= reg2 |
| 8 | mul reg1, reg2 | reg1 *= reg2 |
| 9 | div reg1, reg2 | reg1 /= reg2 (Put the quotient into eax and the remainder into ebx) |
| 10 | xor reg1, reg2 | reg1 ^= reg2 |
| 11 | jmp addr | directly jump to address |
| 12 | cmp reg1, reg2 | edx=reg1-reg2 |
| 13 | jz addr | jump if edx==0（reg1==reg2） |
| 14 | jnz addr | jump if edx!=0（reg1≠reg2） |
| 15 | jg addr | jump if edx>0（reg1>reg2） |
| 16 | jl addr | jump if edx<0 （reg1 < reg2） |
| 17 | InputStr | gets(mem); eax=strlen(mem); |
| 18 | InitMem | memset(mem_addr, 0, sz) |
| 19 | MovRegStack | mov reg, [ebp-src] |
| 20 | MovRegMem | mov reg, mem[src] |
| 0xff | Exit | exit(0) |
from collections import namedtuple
from dataclasses import dataclass
@dataclassclass Regs(object):
idx: int
def __repr__(self):
if self.idx == 0:
return "eax"
elif self.idx == 1:
return "ebx"
elif self.idx == 2:
return "ecx"
elif self.idx == 3:
return "edx"
else:
return "unknown reg {}".format(self.idx)
Nop = namedtuple("Nop", ["addr"]) # case 0: nop
MovReg = namedtuple("MovReg", ["addr", "dst", "imm"]) # case 1: mov reg, imm
PushImm = namedtuple("PushImm", ["addr", "imm"]) # case 2: push imm
PushReg = namedtuple("PushReg", ["addr", "reg"]) # case 3: push reg
PopReg = namedtuple("PopReg", ["addr", "reg"]) # case 4: pop reg
# case 5: print str by edx: 0:'right', 1:'wrong', 3:'plz input:', 4:'hacker'PrintStr = namedtuple("PrintStr", ["addr"])
AddReg = namedtuple("AddReg", ["addr", "dst", "src"]) # case 6: add reg, reg
SubReg = namedtuple("SubReg", ["addr", "dst", "src"]) # case 7: sub reg, reg
MulReg = namedtuple("MulReg", ["addr", "dst", "src"]) # case 8: mul reg, reg
DivReg = namedtuple("DivReg", ["addr", "dst", "src"]) # case 9: div reg, reg
XorReg = namedtuple("XorReg", ["addr", "dst", "src"]) # case 10: xor reg, reg
Jmp = namedtuple("Jmp", ["addr", "target"]) # case 11: jmp addr
Cmp = namedtuple("Cmp", ["addr", "dst", "src"]) # case 12: cmp reg, reg
Jz = namedtuple("Jz", ["addr", "target"]) # case 13: jz addr
Jnz = namedtuple("Jnz", ["addr", "target"]) # case 14: jnz addr
Jg = namedtuple("Jg", ["addr", "target"]) # case 15: jg addr
Jl = namedtuple("Jl", ["addr", "target"]) # case 16: jl addr
# case 17: gets(mem); eax=strlen(mem);InputStr = namedtuple("InputStr", ["addr"])
InitMem = namedtuple(
"InitMem", ["addr", "mem_addr", "sz"]
) # case 18: memset(mem_addr, 0, sz)
MovRegStack = namedtuple(
"MovRegStack", ["addr", "dst", "src"]
) # case 19: mov reg, [ebp-src]
MovRegMem = namedtuple(
"MovRegMem", ["addr", "dst", "src"]
) # case 20: mov reg, mem[src]
Exit = namedtuple("Exit", ["addr"]) # case 0xff: exit(0)
def parse(buffer):
instructions = []
pc = 0
while pc < len(buffer):
opcode = buffer[pc]
match opcode:
case 0:
instructions.append(Nop(pc))
pc += 1
case 1:
dst = buffer[pc + 1]
imm = buffer[pc + 2]
instructions.append(MovReg(pc, Regs(dst), imm))
pc += 3
case 2:
imm = buffer[pc + 1]
instructions.append(PushImm(pc, imm))
pc += 3
case 3:
reg = buffer[pc + 1]
instructions.append(PushReg(pc, Regs(reg)))
pc += 3
case 4:
reg = buffer[pc + 1]
instructions.append(PopReg(pc, Regs(reg)))
pc += 3
case 5:
instructions.append(PrintStr(pc))
pc += 3
case 6:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(AddReg(pc, Regs(dst), Regs(src)))
pc += 3
case 7:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(SubReg(pc, Regs(dst), Regs(src)))
pc += 3
case 8:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MulReg(pc, Regs(dst), Regs(src)))
pc += 3
case 9:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(DivReg(pc, Regs(dst), Regs(src)))
pc += 3
case 10:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(XorReg(pc, Regs(dst), Regs(src)))
pc += 3
case 11:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jmp(pc, target))
pc += 3
case 12:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(Cmp(pc, Regs(dst), Regs(src)))
pc += 3
case 13:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jz(pc, target))
pc += 3
case 14:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jnz(pc, target))
pc += 3
case 15:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jg(pc, target))
pc += 3
case 16:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jl(pc, target))
pc += 3
case 17:
instructions.append(InputStr(pc))
pc += 3
case 18:
mem_addr = buffer[pc + 1]
sz = buffer[pc + 2]
instructions.append(InitMem(pc, mem_addr, sz))
pc += 3
case 19:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegStack(pc, Regs(dst), Regs(src)))
pc += 3
case 20:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegMem(pc, Regs(dst), Regs(src)))
pc += 3
case 255:
instructions.append(Exit(pc))
pc += 3
case _:
raise Exception(f"unknown opcode: {opcode} at {pc}")
break
return instructions
if __name__ == '__main__':
opcode = [0x01, 0x03, 0x03, 0x05, 0x00, 0x00, 0x11, 0x00, 0x00, 0x01, 0x01, 0x11, 0x0C, 0x00, 0x01, 0x0D, 0x0A, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x02, 0x00, 0x01, 0x00, 0x11, 0x0C, 0x00, 0x02, 0x0D, 0x2B, 0x00, 0x14, 0x00, 0x02, 0x01, 0x01, 0x61, 0x0C, 0x00, 0x01, 0x10, 0x1A, 0x00, 0x01, 0x01, 0x7A, 0x0C, 0x00, 0x01, 0x0F, 0x1A, 0x00, 0x01, 0x01, 0x47, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x06, 0x00, 0x01, 0x0B, 0x24, 0x00, 0x01, 0x01, 0x41, 0x0C, 0x00, 0x01, 0x10, 0x24, 0x00, 0x01, 0x01, 0x5A, 0x0C, 0x00, 0x01, 0x0F, 0x24, 0x00, 0x01, 0x01, 0x4B, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x07, 0x00, 0x01, 0x01, 0x01, 0x10, 0x09, 0x00, 0x01, 0x03, 0x01, 0x00, 0x03, 0x00, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x0B, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x00, 0x00, 0x02, 0x05, 0x00, 0x02, 0x01, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x01, 0x00, 0x02, 0x00, 0x00, 0x02, 0x00, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x00, 0x00, 0x02, 0x09, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x03, 0x00, 0x02, 0x00, 0x00, 0x02, 0x02, 0x00, 0x02, 0x05, 0x00, 0x02, 0x03, 0x00, 0x02, 0x03, 0x00, 0x02, 0x01, 0x00, 0x02, 0x07, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0B, 0x00, 0x02, 0x02, 0x00, 0x02, 0x01, 0x00, 0x02, 0x02, 0x00, 0x02, 0x07, 0x00, 0x02, 0x02, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x02, 0x00, 0x02, 0x02, 0x00, 0x01, 0x02, 0x01, 0x13, 0x01, 0x02, 0x04, 0x00, 0x00, 0x0C, 0x00, 0x01, 0x0E, 0x5B, 0x00, 0x01, 0x01, 0x22, 0x0C, 0x02, 0x01, 0x0D, 0x59, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x4E, 0x00, 0x01, 0x03, 0x00, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00]
instructions = parse(opcode)
for ins in instructions:
print(ins)
from collections import namedtuple
from dataclasses import dataclass
@dataclassclass Regs(object):
idx: int
def __repr__(self):
if self.idx == 0:
return "eax"
elif self.idx == 1:
return "ebx"
elif self.idx == 2:
return "ecx"
elif self.idx == 3:
return "edx"
else:
return "unknown reg {}".format(self.idx)
Nop = namedtuple("Nop", ["addr"]) # case 0: nop
MovReg = namedtuple("MovReg", ["addr", "dst", "imm"]) # case 1: mov reg, imm
PushImm = namedtuple("PushImm", ["addr", "imm"]) # case 2: push imm
PushReg = namedtuple("PushReg", ["addr", "reg"]) # case 3: push reg
PopReg = namedtuple("PopReg", ["addr", "reg"]) # case 4: pop reg
# case 5: print str by edx: 0:'right', 1:'wrong', 3:'plz input:', 4:'hacker'PrintStr = namedtuple("PrintStr", ["addr"])
AddReg = namedtuple("AddReg", ["addr", "dst", "src"]) # case 6: add reg, reg
SubReg = namedtuple("SubReg", ["addr", "dst", "src"]) # case 7: sub reg, reg
MulReg = namedtuple("MulReg", ["addr", "dst", "src"]) # case 8: mul reg, reg
DivReg = namedtuple("DivReg", ["addr", "dst", "src"]) # case 9: div reg, reg
XorReg = namedtuple("XorReg", ["addr", "dst", "src"]) # case 10: xor reg, reg
Jmp = namedtuple("Jmp", ["addr", "target"]) # case 11: jmp addr
Cmp = namedtuple("Cmp", ["addr", "dst", "src"]) # case 12: cmp reg, reg
Jz = namedtuple("Jz", ["addr", "target"]) # case 13: jz addr
Jnz = namedtuple("Jnz", ["addr", "target"]) # case 14: jnz addr
Jg = namedtuple("Jg", ["addr", "target"]) # case 15: jg addr
Jl = namedtuple("Jl", ["addr", "target"]) # case 16: jl addr
# case 17: gets(mem); eax=strlen(mem);InputStr = namedtuple("InputStr", ["addr"])
InitMem = namedtuple(
"InitMem", ["addr", "mem_addr", "sz"]
) # case 18: memset(mem_addr, 0, sz)
MovRegStack = namedtuple(
"MovRegStack", ["addr", "dst", "src"]
) # case 19: mov reg, [ebp-src]
MovRegMem = namedtuple(
"MovRegMem", ["addr", "dst", "src"]
) # case 20: mov reg, mem[src]
Exit = namedtuple("Exit", ["addr"]) # case 0xff: exit(0)
def parse(buffer):
instructions = []
pc = 0
while pc < len(buffer):
opcode = buffer[pc]
match opcode:
case 0:
instructions.append(Nop(pc))
pc += 1
case 1:
dst = buffer[pc + 1]
imm = buffer[pc + 2]
instructions.append(MovReg(pc, Regs(dst), imm))
pc += 3
case 2:
imm = buffer[pc + 1]
instructions.append(PushImm(pc, imm))
pc += 3
case 3:
reg = buffer[pc + 1]
instructions.append(PushReg(pc, Regs(reg)))
pc += 3
case 4:
reg = buffer[pc + 1]
instructions.append(PopReg(pc, Regs(reg)))
pc += 3
case 5:
instructions.append(PrintStr(pc))
pc += 3
case 6:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(AddReg(pc, Regs(dst), Regs(src)))
pc += 3
case 7:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(SubReg(pc, Regs(dst), Regs(src)))
pc += 3
case 8:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MulReg(pc, Regs(dst), Regs(src)))
pc += 3
case 9:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(DivReg(pc, Regs(dst), Regs(src)))
pc += 3
case 10:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(XorReg(pc, Regs(dst), Regs(src)))
pc += 3
case 11:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jmp(pc, target))
pc += 3
case 12:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(Cmp(pc, Regs(dst), Regs(src)))
pc += 3
case 13:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jz(pc, target))
pc += 3
case 14:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jnz(pc, target))
pc += 3
case 15:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jg(pc, target))
pc += 3
case 16:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jl(pc, target))
pc += 3
case 17:
instructions.append(InputStr(pc))
pc += 3
case 18:
mem_addr = buffer[pc + 1]
sz = buffer[pc + 2]
instructions.append(InitMem(pc, mem_addr, sz))
pc += 3
case 19:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegStack(pc, Regs(dst), Regs(src)))
pc += 3
case 20:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegMem(pc, Regs(dst), Regs(src)))
pc += 3
case 255:
instructions.append(Exit(pc))
pc += 3
case _:
raise Exception(f"unknown opcode: {opcode} at {pc}")
break
return instructions
if __name__ == '__main__':
opcode = [0x01, 0x03, 0x03, 0x05, 0x00, 0x00, 0x11, 0x00, 0x00, 0x01, 0x01, 0x11, 0x0C, 0x00, 0x01, 0x0D, 0x0A, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x02, 0x00, 0x01, 0x00, 0x11, 0x0C, 0x00, 0x02, 0x0D, 0x2B, 0x00, 0x14, 0x00, 0x02, 0x01, 0x01, 0x61, 0x0C, 0x00, 0x01, 0x10, 0x1A, 0x00, 0x01, 0x01, 0x7A, 0x0C, 0x00, 0x01, 0x0F, 0x1A, 0x00, 0x01, 0x01, 0x47, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x06, 0x00, 0x01, 0x0B, 0x24, 0x00, 0x01, 0x01, 0x41, 0x0C, 0x00, 0x01, 0x10, 0x24, 0x00, 0x01, 0x01, 0x5A, 0x0C, 0x00, 0x01, 0x0F, 0x24, 0x00, 0x01, 0x01, 0x4B, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x07, 0x00, 0x01, 0x01, 0x01, 0x10, 0x09, 0x00, 0x01, 0x03, 0x01, 0x00, 0x03, 0x00, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x0B, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x00, 0x00, 0x02, 0x05, 0x00, 0x02, 0x01, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x01, 0x00, 0x02, 0x00, 0x00, 0x02, 0x00, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x00, 0x00, 0x02, 0x09, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x03, 0x00, 0x02, 0x00, 0x00, 0x02, 0x02, 0x00, 0x02, 0x05, 0x00, 0x02, 0x03, 0x00, 0x02, 0x03, 0x00, 0x02, 0x01, 0x00, 0x02, 0x07, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0B, 0x00, 0x02, 0x02, 0x00, 0x02, 0x01, 0x00, 0x02, 0x02, 0x00, 0x02, 0x07, 0x00, 0x02, 0x02, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x02, 0x00, 0x02, 0x02, 0x00, 0x01, 0x02, 0x01, 0x13, 0x01, 0x02, 0x04, 0x00, 0x00, 0x0C, 0x00, 0x01, 0x0E, 0x5B, 0x00, 0x01, 0x01, 0x22, 0x0C, 0x02, 0x01, 0x0D, 0x59, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x4E, 0x00, 0x01, 0x03, 0x00, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00]
instructions = parse(opcode)
for ins in instructions:
print(ins)
MovReg(addr=0, dst=edx, imm=3)
PrintStr(addr=3)
InputStr(addr=6)
MovReg(addr=9, dst=ebx, imm=17)
Cmp(addr=12, dst=eax, src=ebx)
Jz(addr=15, target=27)
MovReg(addr=18, dst=edx, imm=1)
PrintStr(addr=21)
Exit(addr=24)
MovReg(addr=27, dst=ecx, imm=0)
MovReg(addr=30, dst=eax, imm=17)
Cmp(addr=33, dst=eax, src=ecx)
Jz(addr=36, target=126)
MovRegMem(addr=39, dst=eax, src=ecx)
MovReg(addr=42, dst=ebx, imm=97)
Cmp(addr=45, dst=eax, src=ebx)
Jl(addr=48, target=75)
MovReg(addr=51, dst=ebx, imm=122)
Cmp(addr=54, dst=eax, src=ebx)
Jg(addr=57, target=75)
MovReg(addr=60, dst=ebx, imm=71)
XorReg(addr=63, dst=eax, src=ebx)
MovReg(addr=66, dst=ebx, imm=1)
AddReg(addr=69, dst=eax, src=ebx)
Jmp(addr=72, target=105)
MovReg(addr=75, dst=ebx, imm=65)
Cmp(addr=78, dst=eax, src=ebx)
Jl(addr=81, target=105)
MovReg(addr=84, dst=ebx, imm=90)
Cmp(addr=87, dst=eax, src=ebx)
Jg(addr=90, target=105)
MovReg(addr=93, dst=ebx, imm=75)
XorReg(addr=96, dst=eax, src=ebx)
MovReg(addr=99, dst=ebx, imm=1)
SubReg(addr=102, dst=eax, src=ebx)
MovReg(addr=105, dst=ebx, imm=16)
DivReg(addr=108, dst=eax, src=ebx)
PushReg(addr=111, reg=ebx)
PushReg(addr=114, reg=eax)
MovReg(addr=117, dst=ebx, imm=1)
AddReg(addr=120, dst=ecx, src=ebx)
Jmp(addr=123, target=30)
PushImm(addr=126, imm=7)
PushImm(addr=129, imm=13)
PushImm(addr=132, imm=0)
PushImm(addr=135, imm=5)
PushImm(addr=138, imm=1)
PushImm(addr=141, imm=12)
PushImm(addr=144, imm=1)
PushImm(addr=147, imm=0)
PushImm(addr=150, imm=0)
PushImm(addr=153, imm=13)
PushImm(addr=156, imm=5)
PushImm(addr=159, imm=15)
PushImm(addr=162, imm=0)
PushImm(addr=165, imm=9)
PushImm(addr=168, imm=5)
PushImm(addr=171, imm=15)
PushImm(addr=174, imm=3)
PushImm(addr=177, imm=0)
PushImm(addr=180, imm=2)
PushImm(addr=183, imm=5)
PushImm(addr=186, imm=3)
PushImm(addr=189, imm=3)
PushImm(addr=192, imm=1)
PushImm(addr=195, imm=7)
PushImm(addr=198, imm=7)
PushImm(addr=201, imm=11)
PushImm(addr=204, imm=2)
PushImm(addr=207, imm=1)
PushImm(addr=210, imm=2)
PushImm(addr=213, imm=7)
PushImm(addr=216, imm=2)
PushImm(addr=219, imm=12)
PushImm(addr=222, imm=2)
PushImm(addr=225, imm=2)
MovReg(addr=228, dst=ecx, imm=1)
MovRegStack(addr=231, dst=ebx, src=ecx)
PopReg(addr=234, reg=eax)
Cmp(addr=237, dst=eax, src=ebx)
Jnz(addr=240, target=270)
MovReg(addr=243, dst=ebx, imm=34)
Cmp(addr=246, dst=ecx, src=ebx)
Jz(addr=249, target=264)
MovReg(addr=252, dst=ebx, imm=1)
AddReg(addr=255, dst=ecx, src=ebx)
Jmp(addr=258, target=231)
MovReg(addr=261, dst=edx, imm=0)
PrintStr(addr=264)
Exit(addr=267)
MovReg(addr=270, dst=edx, imm=1)
PrintStr(addr=273)
Exit(addr=276)
Nop(addr=279)
MovReg(addr=0, dst=edx, imm=3)
PrintStr(addr=3)
InputStr(addr=6)
MovReg(addr=9, dst=ebx, imm=17)
Cmp(addr=12, dst=eax, src=ebx)
Jz(addr=15, target=27)
MovReg(addr=18, dst=edx, imm=1)
PrintStr(addr=21)
Exit(addr=24)
MovReg(addr=27, dst=ecx, imm=0)
MovReg(addr=30, dst=eax, imm=17)
Cmp(addr=33, dst=eax, src=ecx)
Jz(addr=36, target=126)
MovRegMem(addr=39, dst=eax, src=ecx)
MovReg(addr=42, dst=ebx, imm=97)
Cmp(addr=45, dst=eax, src=ebx)
Jl(addr=48, target=75)
MovReg(addr=51, dst=ebx, imm=122)
Cmp(addr=54, dst=eax, src=ebx)
Jg(addr=57, target=75)
MovReg(addr=60, dst=ebx, imm=71)
XorReg(addr=63, dst=eax, src=ebx)
MovReg(addr=66, dst=ebx, imm=1)
AddReg(addr=69, dst=eax, src=ebx)
Jmp(addr=72, target=105)
MovReg(addr=75, dst=ebx, imm=65)
Cmp(addr=78, dst=eax, src=ebx)
Jl(addr=81, target=105)
MovReg(addr=84, dst=ebx, imm=90)
Cmp(addr=87, dst=eax, src=ebx)
Jg(addr=90, target=105)
MovReg(addr=93, dst=ebx, imm=75)
XorReg(addr=96, dst=eax, src=ebx)
MovReg(addr=99, dst=ebx, imm=1)
SubReg(addr=102, dst=eax, src=ebx)
MovReg(addr=105, dst=ebx, imm=16)
DivReg(addr=108, dst=eax, src=ebx)
PushReg(addr=111, reg=ebx)
PushReg(addr=114, reg=eax)
MovReg(addr=117, dst=ebx, imm=1)
AddReg(addr=120, dst=ecx, src=ebx)
Jmp(addr=123, target=30)
PushImm(addr=126, imm=7)
PushImm(addr=129, imm=13)
PushImm(addr=132, imm=0)
PushImm(addr=135, imm=5)
PushImm(addr=138, imm=1)
PushImm(addr=141, imm=12)
PushImm(addr=144, imm=1)
PushImm(addr=147, imm=0)
PushImm(addr=150, imm=0)
PushImm(addr=153, imm=13)
PushImm(addr=156, imm=5)
PushImm(addr=159, imm=15)
PushImm(addr=162, imm=0)
PushImm(addr=165, imm=9)
PushImm(addr=168, imm=5)
PushImm(addr=171, imm=15)
PushImm(addr=174, imm=3)
PushImm(addr=177, imm=0)
PushImm(addr=180, imm=2)
PushImm(addr=183, imm=5)
PushImm(addr=186, imm=3)
PushImm(addr=189, imm=3)
PushImm(addr=192, imm=1)
PushImm(addr=195, imm=7)
PushImm(addr=198, imm=7)
PushImm(addr=201, imm=11)
PushImm(addr=204, imm=2)
PushImm(addr=207, imm=1)
PushImm(addr=210, imm=2)
PushImm(addr=213, imm=7)
PushImm(addr=216, imm=2)
PushImm(addr=219, imm=12)
PushImm(addr=222, imm=2)
PushImm(addr=225, imm=2)
MovReg(addr=228, dst=ecx, imm=1)
MovRegStack(addr=231, dst=ebx, src=ecx)
PopReg(addr=234, reg=eax)
Cmp(addr=237, dst=eax, src=ebx)
Jnz(addr=240, target=270)
MovReg(addr=243, dst=ebx, imm=34)
Cmp(addr=246, dst=ecx, src=ebx)
Jz(addr=249, target=264)
MovReg(addr=252, dst=ebx, imm=1)
AddReg(addr=255, dst=ecx, src=ebx)
Jmp(addr=258, target=231)
MovReg(addr=261, dst=edx, imm=0)
PrintStr(addr=264)
Exit(addr=267)
MovReg(addr=270, dst=edx, imm=1)
PrintStr(addr=273)
Exit(addr=276)
Nop(addr=279)
from collections import namedtuple
from dataclasses import dataclass
@dataclassclass Regs(object):
idx: int
def __repr__(self):
if self.idx == 0:
return "eax"
elif self.idx == 1:
return "ebx"
elif self.idx == 2:
return "ecx"
elif self.idx == 3:
return "edx"
else:
return "unknown reg {}".format(self.idx)
Nop = namedtuple("Nop", ["addr"]) # case 0: nop
MovReg = namedtuple("MovReg", ["addr", "dst", "imm"]) # case 1: mov reg, imm
PushImm = namedtuple("PushImm", ["addr", "imm"]) # case 2: push imm
PushReg = namedtuple("PushReg", ["addr", "reg"]) # case 3: push reg
PopReg = namedtuple("PopReg", ["addr", "reg"]) # case 4: pop reg
# case 5: print str by edx: 0:'right', 1:'wrong', 3:'plz input:', 4:'hacker'PrintStr = namedtuple("PrintStr", ["addr"])
AddReg = namedtuple("AddReg", ["addr", "dst", "src"]) # case 6: add reg, reg
SubReg = namedtuple("SubReg", ["addr", "dst", "src"]) # case 7: sub reg, reg
MulReg = namedtuple("MulReg", ["addr", "dst", "src"]) # case 8: mul reg, reg
DivReg = namedtuple("DivReg", ["addr", "dst", "src"]) # case 9: div reg, reg
XorReg = namedtuple("XorReg", ["addr", "dst", "src"]) # case 10: xor reg, reg
Jmp = namedtuple("Jmp", ["addr", "target"]) # case 11: jmp addr
Cmp = namedtuple("Cmp", ["addr", "dst", "src"]) # case 12: cmp reg, reg
Jz = namedtuple("Jz", ["addr", "target"]) # case 13: jz addr
Jnz = namedtuple("Jnz", ["addr", "target"]) # case 14: jnz addr
Jg = namedtuple("Jg", ["addr", "target"]) # case 15: jg addr
Jl = namedtuple("Jl", ["addr", "target"]) # case 16: jl addr
# case 17: gets(mem); eax=strlen(mem);InputStr = namedtuple("InputStr", ["addr"])
InitMem = namedtuple(
"InitMem", ["addr", "mem_addr", "sz"]
) # case 18: memset(mem_addr, 0, sz)
MovRegStack = namedtuple(
"MovRegStack", ["addr", "dst", "src"]
) # case 19: mov reg, [ebp-src]
MovRegMem = namedtuple(
"MovRegMem", ["addr", "dst", "src"]
) # case 20: mov reg, mem[src]
Exit = namedtuple("Exit", ["addr"]) # case 0xff: exit(0)
def parse(buffer):
instructions = []
pc = 0
while pc < len(buffer):
opcode = buffer[pc]
match opcode:
case 0:
instructions.append(Nop(pc))
pc += 1
case 1:
dst = buffer[pc + 1]
imm = buffer[pc + 2]
instructions.append(MovReg(pc, Regs(dst), imm))
pc += 3
case 2:
imm = buffer[pc + 1]
instructions.append(PushImm(pc, imm))
pc += 3
case 3:
reg = buffer[pc + 1]
instructions.append(PushReg(pc, Regs(reg)))
pc += 3
case 4:
reg = buffer[pc + 1]
instructions.append(PopReg(pc, Regs(reg)))
pc += 3
case 5:
instructions.append(PrintStr(pc))
pc += 3
case 6:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(AddReg(pc, Regs(dst), Regs(src)))
pc += 3
case 7:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(SubReg(pc, Regs(dst), Regs(src)))
pc += 3
case 8:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MulReg(pc, Regs(dst), Regs(src)))
pc += 3
case 9:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(DivReg(pc, Regs(dst), Regs(src)))
pc += 3
case 10:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(XorReg(pc, Regs(dst), Regs(src)))
pc += 3
case 11:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jmp(pc, target))
pc += 3
case 12:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(Cmp(pc, Regs(dst), Regs(src)))
pc += 3
case 13:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jz(pc, target))
pc += 3
case 14:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jnz(pc, target))
pc += 3
case 15:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jg(pc, target))
pc += 3
case 16:
target = 3 * buffer[pc + 1] - 3
instructions.append(Jl(pc, target))
pc += 3
case 17:
instructions.append(InputStr(pc))
pc += 3
case 18:
mem_addr = buffer[pc + 1]
sz = buffer[pc + 2]
instructions.append(InitMem(pc, mem_addr, sz))
pc += 3
case 19:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegStack(pc, Regs(dst), src))
pc += 3
case 20:
dst = buffer[pc + 1]
src = buffer[pc + 2]
instructions.append(MovRegMem(pc, Regs(dst), src))
pc += 3
case 255:
instructions.append(Exit(pc))
pc += 3
case _:
raise Exception(f"unknown opcode: {opcode} at {pc}")
break
return instructions
def dump(instructions):
for ins in instructions:
match ins:
case Nop(addr):
print(f"_0x{addr:04x}: nop")
case MovReg(addr, dst, imm):
print(f"_0x{addr:04x}: mov {dst}, 0x{imm:02x}")
case PushImm(addr, imm):
print(f"_0x{addr:04x}: push 0x{imm:02x}")
case PushReg(addr, reg):
print(f"_0x{addr:04x}: push {reg}")
case PopReg(addr, reg):
print(f"_0x{addr:04x}: pop {reg}")
case PrintStr(addr):
print(f"_0x{addr:04x}: print_str")
case AddReg(addr, dst, src):
print(f"_0x{addr:04x}: add {dst}, {src}")
case SubReg(addr, dst, src):
print(f"_0x{addr:04x}: sub {dst}, {src}")
case MulReg(addr, dst, src):
print(f"_0x{addr:04x}: mul {dst}, {src}")
case DivReg(addr, dst, src):
print(f"_0x{addr:04x}: div {dst}, {src}")
case XorReg(addr, dst, src):
print(f"_0x{addr:04x}: xor {dst}, {src}")
case Jmp(addr, target):
print(f"_0x{addr:04x}: jmp _0x{target:04x}")
case Cmp(addr, dst, src):
print(f"_0x{addr:04x}: cmp {dst}, {src}")
case Jz(addr, target):
print(f"_0x{addr:04x}: jz _0x{target:04x}")
case Jnz(addr, target):
print(f"_0x{addr:04x}: jnz _0x{target:04x}")
case Jg(addr, target):
print(f"_0x{addr:04x}: jg _0x{target:04x}")
case Jl(addr, target):
print(f"_0x{addr:04x}: jl _0x{target:04x}")
case InputStr(addr):
print(f"_0x{addr:04x}: input_str")
case InitMem(addr, mem_addr, sz):
print(f"_0x{addr:04x}: memset(0x{mem_addr:02x},0,{sz})")
case MovRegStack(addr, dst, src):
print(f"_0x{addr:04x}: mov {dst}, [ebp-{src}]")
case MovRegMem(addr, dst, src):
print(f"_0x{addr:04x}: mov {dst}, mem[{src}]")
case Exit(addr):
print(f"_0x{addr:04x}: exit(0)")
case _:
raise Exception(f"unknown instruction: {ins}")
break
if __name__ == '__main__':
opcode = [0x01, 0x03, 0x03, 0x05, 0x00, 0x00, 0x11, 0x00, 0x00, 0x01, 0x01, 0x11, 0x0C, 0x00, 0x01, 0x0D, 0x0A, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x02, 0x00, 0x01, 0x00, 0x11, 0x0C, 0x00, 0x02, 0x0D, 0x2B, 0x00, 0x14, 0x00, 0x02, 0x01, 0x01, 0x61, 0x0C, 0x00, 0x01, 0x10, 0x1A, 0x00, 0x01, 0x01, 0x7A, 0x0C, 0x00, 0x01, 0x0F, 0x1A, 0x00, 0x01, 0x01, 0x47, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x06, 0x00, 0x01, 0x0B, 0x24, 0x00, 0x01, 0x01, 0x41, 0x0C, 0x00, 0x01, 0x10, 0x24, 0x00, 0x01, 0x01, 0x5A, 0x0C, 0x00, 0x01, 0x0F, 0x24, 0x00, 0x01, 0x01, 0x4B, 0x0A, 0x00, 0x01, 0x01, 0x01, 0x01, 0x07, 0x00, 0x01, 0x01, 0x01, 0x10, 0x09, 0x00, 0x01, 0x03, 0x01, 0x00, 0x03, 0x00, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x0B, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x00, 0x00, 0x02, 0x05, 0x00, 0x02, 0x01, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x01, 0x00, 0x02, 0x00, 0x00, 0x02, 0x00, 0x00, 0x02, 0x0D, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x00, 0x00, 0x02, 0x09, 0x00, 0x02, 0x05, 0x00, 0x02, 0x0F, 0x00, 0x02, 0x03, 0x00, 0x02, 0x00, 0x00, 0x02, 0x02, 0x00, 0x02, 0x05, 0x00, 0x02, 0x03, 0x00, 0x02, 0x03, 0x00, 0x02, 0x01, 0x00, 0x02, 0x07, 0x00, 0x02, 0x07, 0x00, 0x02, 0x0B, 0x00, 0x02, 0x02, 0x00, 0x02, 0x01, 0x00, 0x02, 0x02, 0x00, 0x02, 0x07, 0x00, 0x02, 0x02, 0x00, 0x02, 0x0C, 0x00, 0x02, 0x02, 0x00, 0x02, 0x02, 0x00, 0x01, 0x02, 0x01, 0x13, 0x01, 0x02, 0x04, 0x00, 0x00, 0x0C, 0x00, 0x01, 0x0E, 0x5B, 0x00, 0x01, 0x01, 0x22, 0x0C, 0x02, 0x01, 0x0D, 0x59, 0x00, 0x01, 0x01, 0x01, 0x06, 0x02, 0x01, 0x0B, 0x4E, 0x00, 0x01, 0x03, 0x00, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x01, 0x03, 0x01, 0x05, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00]
instructions = parse(opcode)
dump(instructions)
from collections import namedtuple
from dataclasses import dataclass
@dataclassclass Regs(object):
idx: int
def __repr__(self):
if self.idx == 0:
return "eax"
elif self.idx == 1:
return "ebx"
elif self.idx == 2:
return "ecx"
elif self.idx == 3:
return "edx"
else:
return "unknown reg {}".format(self.idx)
Nop = namedtuple("Nop", ["addr"]) # case 0: nop
MovReg = namedtuple("MovReg", ["addr", "dst", "imm"]) # case 1: mov reg, imm
PushImm = namedtuple("PushImm", ["addr", "imm"]) # case 2: push imm
PushReg = namedtuple("PushReg", ["addr", "reg"]) # case 3: push reg
PopReg = namedtuple("PopReg", ["addr", "reg"]) # case 4: pop reg
# case 5: print str by edx: 0:'right', 1:'wrong', 3:'plz input:', 4:'hacker'PrintStr = namedtuple("PrintStr", ["addr"])
AddReg = namedtuple("AddReg", ["addr", "dst", "src"]) # case 6: add reg, reg
SubReg = namedtuple("SubReg", ["addr", "dst", "src"]) # case 7: sub reg, reg
MulReg = namedtuple("MulReg", ["addr", "dst", "src"]) # case 8: mul reg, reg
DivReg = namedtuple("DivReg", ["addr", "dst", "src"]) # case 9: div reg, reg
XorReg = namedtuple("XorReg", ["addr", "dst", "src"]) # case 10: xor reg, reg
Jmp = namedtuple("Jmp", ["addr", "target"]) # case 11: jmp addr
Cmp = namedtuple("Cmp", ["addr", "dst", "src"]) # case 12: cmp reg, reg
Jz = namedtuple("Jz", ["addr", "target"]) # case 13: jz addr
Jnz = namedtuple("Jnz", ["addr", "target"]) # case 14: jnz addr
Jg = namedtuple("Jg", ["addr", "target"]) # case 15: jg addr
Jl = namedtuple("Jl", ["addr", "target"]) # case 16: jl addr
# case 17: gets(mem); eax=strlen(mem);InputStr = namedtuple("InputStr", ["addr"])
InitMem = namedtuple(
"InitMem", ["addr", "mem_addr", "sz"]
) # case 18: memset(mem_addr, 0, sz)
MovRegStack = namedtuple(
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