#!/usr/bin/env python3
"""Behavior-focused static reverse: resolve the real main from the CRT stub,
map every import call-site in .text to its API, dump resource directory + carve
embedded PE/streams. No IDA. x64 only for call-site RIP resolution.

Usage: python pe_behavior.py <path.exe>
"""
from __future__ import annotations
import sys, struct
import pefile
from capstone import Cs, CS_ARCH_X86, CS_MODE_64
from capstone.x86 import X86_OP_MEM, X86_OP_IMM, X86_REG_RIP


def main():
    path = sys.argv[1]
    pe = pefile.PE(path, fast_load=False)
    base = pe.OPTIONAL_HEADER.ImageBase
    md = Cs(CS_ARCH_X86, CS_MODE_64); md.detail = True

    # IAT slot VA -> name
    iat = {}
    for entry in getattr(pe, "DIRECTORY_ENTRY_IMPORT", []) or []:
        dll = entry.dll.decode("latin1","replace")
        for imp in entry.imports:
            nm = imp.name.decode("latin1","replace") if imp.name else f"ord{imp.ordinal}"
            if imp.address: iat[imp.address] = f"{dll.split('.')[0]}!{nm}"

    text = [s for s in pe.sections if s.Name.rstrip(b'\x00')==b'.text'][0]
    code = text.get_data()
    text_va = base + text.VirtualAddress

    # Count import call-sites across whole .text (linear sweep).
    from collections import Counter
    calls = Counter()
    callsites = {}   # name -> [addrs]
    for insn in md.disasm(code, text_va):
        if insn.mnemonic in ("call","jmp") and insn.operands:
            op = insn.operands[-1]
            tgt = None
            if op.type == X86_OP_MEM and op.mem.base in (0, X86_REG_RIP):
                tgt = insn.address + insn.size + op.mem.disp
            elif op.type == X86_OP_IMM:
                tgt = op.imm
            if tgt in iat:
                nm = iat[tgt]; calls[nm]+=1
                callsites.setdefault(nm, []).append(insn.address)

    print(f"# {path}")
    print(f"imagebase={hex(base)} .text_va={hex(text_va)} size={len(code)}")
    print("\n== import call-site frequency (behavior surface) ==")
    for nm,c in calls.most_common():
        addrs = ",".join(hex(a) for a in callsites[nm][:4])
        print(f"  {c:3}x  {nm:<32} @ {addrs}")

    # Resource directory dump + carve
    print("\n== resources ==")
    if hasattr(pe,"DIRECTORY_ENTRY_RESOURCE"):
        for t in pe.DIRECTORY_ENTRY_RESOURCE.entries:
            tn = pefile.RESOURCE_TYPE.get(t.id, t.id)
            for r in getattr(t,"directory",{}).entries if hasattr(t,"directory") else []:
                for l in getattr(r,"directory",{}).entries if hasattr(r,"directory") else []:
                    d = l.data.struct
                    print(f"  type={tn} id={r.id} size={d.Size} rva={hex(d.OffsetToData)}")

    # Whole-file embedded PE scan (extractable child?)
    b = open(path,"rb").read()
    print("\n== embedded PE scan ==")
    cnt=0
    for i in range(0, len(b)-0x100):
        if b[i:i+2]==b'MZ':
            e = i + int.from_bytes(b[i+0x3c:i+0x40],'little')
            if 0<e<len(b)-4 and b[e:e+4]==b'PE\x00\x00':
                mach = int.from_bytes(b[e+4:e+6],'little')
                if mach in (0x8664,0x14c):
                    cnt+=1
                    if cnt<=8: print(f"  child PE @ file+{hex(i)} machine={hex(mach)}")
    print(f"  total embedded PE headers: {cnt}")


if __name__ == "__main__":
    main()