Files
hello_js_reverse_skill/tools/tdc_lift.py
T
yml2213 9c889215f2 feat(vm): 提升器按闭包边界切分函数 + 递归展开全部子程序
做了什么:
- tdc_disasm.disassemble_cfg 增加 follow_closures 开关
  (提升单函数时关闭, 避免"子函数体的可达性溢进父函数")
- tdc_lift.run 递归提升所有被引用的闭包: 229 个独立函数
- 函数名统一为 sub_<target>, 便于按 pc 定位

为什么:
- 原来整个程序挤在一个 function 里(闭包 body 与父函数地址连续), 无法按子程序阅读
- AGENTS.md §3.3 步骤5 明确要求"子程序调用(闭包创建)递归展开"

怎么验证:
- .venv/bin/python tools/tdc_lift.py tcaptcha/core_js/tdc_sample.js
  -> lifted functions=229; XTEA 例程 = sub_9109, 内含 r2=(r2+2654435769)
- .venv/bin/python tools/tdc_query.py .../tdc_sample.lifted.txt who r2
  -> sub_9109 @9109: r2 = 0;  @9285: r2 = (r2 + 2654435769);
2026-10-11 22:18:42 +08:00

330 lines
13 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
腾讯天御 Chaos VM —— **字节码提升器 (lifter / devirtualizer)**
对应 AGENTS.md §3.3 步骤 5:「读指令流得到算法;子程序调用(闭包创建)递归展开」。
做什么
------
把栈式字节码**提升为可读伪代码**(不是模拟执行!):
* 表达式栈还原: 每条指令的栈效应翻译成表达式文本
* 寄存器/引用惯用法还原: `PUSH_IMM_ARRAY n`+`MAKE_REG_PROP_REF` -> `rN[key]`
* 控制流: 基本块 + `label`/`goto`/`if (...) goto`
* 闭包: `CREATE_CLOSURE` 递归展开成具名函数 (子程序)
为什么(对比"用 Python 复刻 JS 运行时")
--------------------------------------
* §2.3 铁律2: 复刻 JS 语义 = 打地鼠; 提升只是**读代码**, 不需要任何运行时
* §2.1 最后一步: 读出算法后用目标语言原生重写, 跳过 VM/环境层
* §4.2: 产出可查询资产 ("这个字段谁写的" = 看提升后的赋值语句即可)
用法
----
.venv/bin/python tools/tdc_lift.py tcaptcha/core_js/tdc_sample.js [--func @1518]
输出 `<name>.lifted.txt`
"""
from __future__ import annotations
import os
import re
import sys
from typing import Dict, List, Optional, Tuple
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from tdc_disasm import OP_NAMES, DYNAMIC_ARITY, OP_CREATE_CLOSURE, OP_JUMP, OP_JUMP_IF_TRUE, OP_PUSH_TRY, extract_bytecode, disassemble_cfg # noqa: E402
# 二元运算 => 源码里写出的运算符
BINOP = {
3: "^", 4: "===", 5: "%", 13: "==", 15: ">", 18: "in", 20: ">=", 23: "*",
30: "&", 33: "-", 35: ">>", 36: "<<", 39: "+", 52: "/", 62: "|", 65: ">>>",
}
CMP_PUSH = {19: "true", 29: "null", 42: "undefined", 45: "false", 55: '""', 66: "true"}
def _q(s: str) -> str:
return '"' + s.replace("\\", "\\\\").replace('"', '\\"') + '"'
class Expr:
"""栈上的一个抽象值: 表达式文本 或 引用 (base, key)。"""
__slots__ = ("kind", "text", "base", "key")
def __init__(self, kind, text="", base=None, key=None):
self.kind = kind # "v" = 值表达式, "ref" = 引用
self.text = text
self.base = base
self.key = key
def __str__(self):
if self.kind == "ref":
return f"{self.base.text if isinstance(self.base, Expr) else self.base}" \
f"[{self.key.text if isinstance(self.key, Expr) else self.key}]"
return self.text
def deref(e: Expr) -> str:
return str(e)
class Lifter:
def __init__(self, z: List[int]):
self.z = z
self.funcs: Dict[int, dict] = {} # target pc -> {name}
self.out: List[str] = []
# ------------------------------------------------------------------ 主流程
def run(self, entry: int = 0, name: str = "vm_entry"):
self.out.append(f"// ===== lifted from tdc.js bytecode ({len(self.z)} bytes) =====")
self.funcs[entry] = {"name": name}
self._lift_func(entry, name)
# 递归提升所有被引用到的闭包 (子程序展开)
done = {entry}
while True:
todo = [t for t in self.funcs if t not in done]
if not todo:
break
for t in todo:
done.add(t)
self._lift_func(t, self.funcs[t]["name"])
return "\n".join(self.out)
def _func_name(self, target: int) -> str:
if target not in self.funcs:
self.funcs[target] = {"name": f"sub_{target}"}
return self.funcs[target]["name"]
def _lift_func(self, entry: int, name: str):
insts = {i["pc"]: i for i in disassemble_cfg(self.z, entry, follow_closures=False) if i["pc"] >= entry}
# ---------- 第一遍: 沿执行流传播"求值栈快照"(DFS, 每 pc 记录首次到达时的栈) ----------
state: Dict[int, List[Expr]] = {entry: []}
seen: Dict[int, bool] = {}
work = [entry]
while work:
pc = work.pop()
if pc in seen:
continue
st = list(state.get(pc, []))
while pc in insts and pc not in seen:
seen[pc] = True
state.setdefault(pc, list(st)) # 每条 pc 都记录"进入时的栈"
ins = insts[pc]
self._emit(ins["op"], ins, pc, st, []) # 只改栈, 丢弃语句
op = ins["op"]
ops = ins["operands"] or []
nxt = self._next_pc(ins)
if op == OP_JUMP:
succ = [ops[0]]
elif op == OP_JUMP_IF_TRUE:
succ = [ops[0], nxt]
elif op in (19, 49): # RET_TRUE / THROW
succ = []
else:
succ = [nxt]
for t in succ:
if t in insts and t not in state:
state[t] = list(st)
if t in insts and t not in seen:
work.append(t)
if succ != [nxt]:
break
pc = nxt
# ---------- 第二遍: 按地址序渲染 (块首用快照还原栈) ----------
targets = {entry}
for i in insts.values():
for o in (i.get("operands") or []):
if isinstance(o, int) and o in insts:
targets.add(o)
self.out.append("")
self.out.append(f"function {name}() {{")
pending: List[str] = []
for pc in sorted(insts):
ins = insts[pc]
if ins["op"] is None:
continue
st = list(state.get(pc, []))
if pc in targets:
for x in pending:
self.out.append(" " + x)
pending.clear()
self.out.append(f" @{pc:05d}:")
self._emit(ins["op"], ins, pc, st, pending)
for x in pending:
self.out.append(" " + x)
self.out.append("}")
def _next_pc(self, ins) -> int:
from tdc_disasm import ARITY, DYNAMIC_ARITY
op = ins["op"]; ops = ins["operands"] or []
if op == OP_CREATE_CLOSURE:
capn = self.z[ins["pc"] + 2]; parn = self.z[ins["pc"] + 3]
return ins["pc"] + 1 + 3 + 2 * capn + parn
return ins["pc"] + 1 + ARITY.get(op, 0)
def _fallthrough(self, ins) -> int:
op = ins["op"]
if op == OP_JUMP:
return ins["operands"][0]
if op == OP_JUMP_IF_TRUE:
return ins["operands"][0]
# 其它: 用下一块起点近似 (由 label_needed 决定是否打标签)
return -1
# ------------------------------------------------------- 单条指令的栈效应
def _emit(self, op: int, ins: dict, pc: int, st: List[Expr], out: List[str]):
ops = ins["operands"]
def pop():
return st.pop() if st else Expr("v", "<?>")
def push(t):
st.append(Expr("v", t))
# --- 常量/字符串
if op == 0: # PUSH_STR_CHAR
c = chr(ops[0] & 0xFF)
if st and st[-1].kind == "v" and st[-1].text.startswith('"'):
st[-1].text = st[-1].text[:-1] + c.replace("\\", "\\\\").replace('"', '\\"') + '"'
else:
push(_q(c))
return
if op in CMP_PUSH:
push(CMP_PUSH[op]); return
if op == 22:
push(str(ops[0])); return
if op == 31: # PUSH_IMM_ARRAY -> [n] (寄存器引用惯用法)
push(f"[{ops[0]}]"); return
if op == 64:
if st: st[-1] = Expr("v", str(ops[0]))
else: push(str(ops[0]))
return
# --- 寄存器
if op == 68: # LOAD_REG_IMM r
push(f"r{ops[0]}"); return
if op == 25: # LOAD_REG_INDIRECT: E[key][0]
idx = pop().text
if idx.startswith("[") and idx.endswith("]"):
idx = idx[1:-1]
push(f"r{idx}"); return
if op == 47: # ALLOC_REG r
out.append(f"var r{ops[0]};"); return
if op == 46: # STORE_REG: E[idx][0] = val
val = pop(); ref = pop()
out.append(f"r{ref.text.strip('[]')} = {val};"); return
# --- 引用/属性
if op == 32: # MAKE_REG_PROP_REF: [rN[0], key]
key = pop(); idx = pop()
st.append(Expr("ref", base=Expr("v", f"r{idx.text.strip('[]')}"), key=key)); return
if op == 9: # MAKE_PROP_REF: [base[key0], key]
key = pop(); ref = pop()
st.append(Expr("ref", base=Expr("v", str(ref)), key=key)); return
if op == 59: # GET_PROP
push(str(pop())); return
if op == 8: # GET_GLOBAL_PROP -> c[key]
push(f"c[{pop().text}]"); return
if op == 14: # SET_PROP
val = pop(); ref = pop()
out.append(f"{ref} = {val};"); return
if op == 10:
push(f"typeof {pop().text}"); return
if op == 11:
push(f"delete {pop().text}"); return
if op == 12:
push(f"!{pop().text}"); return
if op == 38:
push(f"Object.keys({pop().text})"); return
# --- 算术/比较
if op in BINOP:
b = pop(); a = pop()
push(f"({a.text} {BINOP[op]} {b.text})"); return
# --- 栈操作
if op == 2:
st.append(Expr("v", st[-1].text) if st else Expr("v", "<?>")); return
if op == 51:
pop(); return
if op == 54: # REVERSE_TOP2 -> [a, b].reverse()
b = pop(); a = pop(); push(f"[{b.text}, {a.text}]"); return
if op == 17: # SWAP n
n = ops[0]
if len(st) >= 2 + n:
i = len(st) - 2 - n
st[i], st[-1] = st[-1], st[i]
return
if op in (53, 42, 69): # SET_STACK_LEN / PUSH_UNDEFINED / CLEAR_EXCEPTION
return
if op == 1:
out.append("// (异常检查: 结束)"); return
# --- 调用
if op in (6, 34, 61, 41):
n = ops[0]
args = [pop().text for _ in range(n)][::-1]
if op == 34:
ref = pop()
push(f"{ref}({', '.join(args)})")
else:
fn = pop()
push(f"{fn.text}({', '.join(args)})")
return
# --- 闭包
if op == OP_CREATE_CLOSURE:
target = self.z[pc + 1]
capn = self.z[pc + 2]
parn = self.z[pc + 3]
pos = pc + 4
caps = []
for _ in range(capn):
caps.append(f"r{self.z[pos]}<-r{self.z[pos+1]}"); pos += 2
params = [f"p{i}->r{self.z[pos+i]}" for i in range(parn)]
nm = self._func_name(target)
out.append(f"// closure {nm}({', '.join(params)}) caps=[{', '.join(caps)}] target=@{target}")
push(nm)
return
# --- 控制流
if op == OP_JUMP:
out.append(f"goto @{ops[0]};"); return
if op == OP_JUMP_IF_TRUE:
c = pop()
out.append(f"if ({c.text}) goto @{ops[0]};"); return
if op == OP_PUSH_TRY:
out.append(f"try {{}} catch -> @{ops[0]} (var r{ops[1]})"); return
if op == 48:
out.append("// pop try"); return
if op == 49:
out.append(f"throw {pop().text};"); return
if op == 26:
push(f"next({pop().text})"); return
if op == 28:
v = pop(); push("[c, " + v.text + "]"); return
# 其它未覆盖: 记录原名, 不破坏栈
out.append(f"// [unhandled {OP_NAMES.get(op, op)} {ops}]")
def main() -> int:
path = sys.argv[1] if len(sys.argv) > 1 else "tcaptcha/core_js/tdc_sample.js"
func = None
if "--func" in sys.argv:
func = int(sys.argv[sys.argv.index("--func") + 1].lstrip("@"))
js = open(path, encoding="utf-8", errors="replace").read()
z = extract_bytecode(js)
lf = Lifter(z)
text = lf.run(func if func is not None else 0, "vm_entry" if func is None else f"func_{func}")
out = path.rsplit(".", 1)[0] + ".lifted.txt"
with open(out, "w", encoding="utf-8") as f:
f.write(text + "\n")
print(f"bytecode={len(z)} lifted functions={len(lf.funcs)} -> {out}")
print("--- 头 40 行 ---")
print("\n".join(text.splitlines()[:40]))
return 0
if __name__ == "__main__":
raise SystemExit(main())