python Decompilation of exe File to Instance Code of py File

  • 2021-07-03 00:30:48
  • OfStack

We use pyinstaller to package friend files into exe files, but sometimes we need to restore them, so we can use pyinstxtractor. py

Usage:

python pyinstxtractor.py xxx.exe

After that, I get a folder with this structure


--- xxx.exe_extracted
  -- out00-PYZ.pyz_extracted
   -  Various .pyc Documents 
  -- out00-PYZ.pyz
  -- some
  -- others
  -- xxx( Note that these are all without suffixes )

And then the terminal pip install uncompyle Install uncompyle,

Then you can use it

uncompyle6 input.pyc > output.py

Transform pyc file into py file, hoping to help everyone

Finally, paste the code of pyinstxtractor. py


"""
PyInstaller Extractor v1.9 (Supports pyinstaller 3.3, 3.2, 3.1, 3.0, 2.1, 2.0)
Author : Extreme Coders
E-mail : extremecoders(at)hotmail(dot)com
Web  : https://0xec.blogspot.com
Date  : 29-November-2017
Url  : https://sourceforge.net/projects/pyinstallerextractor/
For any suggestions, leave a comment on
https://forum.tuts4you.com/topic/34455-pyinstaller-extractor/
This script extracts a pyinstaller generated executable file.
Pyinstaller installation is not needed. The script has it all.
For best results, it is recommended to run this script in the
same version of python as was used to create the executable.
This is just to prevent unmarshalling errors(if any) while
extracting the PYZ archive.
Usage : Just copy this script to the directory where your exe resides
    and run the script with the exe file name as a parameter
C:\path\to\exe\>python pyinstxtractor.py <filename>
$ /path/to/exe/python pyinstxtractor.py <filename>
Licensed under GNU General Public License (GPL) v3.
You are free to modify this source.
CHANGELOG
================================================
Version 1.1 (Jan 28, 2014)
-------------------------------------------------
- First Release
- Supports only pyinstaller 2.0
Version 1.2 (Sept 12, 2015)
-------------------------------------------------
- Added support for pyinstaller 2.1 and 3.0 dev
- Cleaned up code
- Script is now more verbose
- Executable extracted within a dedicated sub-directory
(Support for pyinstaller 3.0 dev is experimental)
Version 1.3 (Dec 12, 2015)
-------------------------------------------------
- Added support for pyinstaller 3.0 final
- Script is compatible with both python 2.x & 3.x (Thanks to Moritz Kroll @ Avira Operations GmbH & Co. KG)
Version 1.4 (Jan 19, 2016)
-------------------------------------------------
- Fixed a bug when writing pyc files >= version 3.3 (Thanks to Daniello Alto: https://github.com/Djamana)
Version 1.5 (March 1, 2016)
-------------------------------------------------
- Added support for pyinstaller 3.1 (Thanks to Berwyn Hoyt for reporting)
Version 1.6 (Sept 5, 2016)
-------------------------------------------------
- Added support for pyinstaller 3.2
- Extractor will use a random name while extracting unnamed files.
- For encrypted pyz archives it will dump the contents as is. Previously, the tool would fail.
Version 1.7 (March 13, 2017)
-------------------------------------------------
- Made the script compatible with python 2.6 (Thanks to Ross for reporting)
Version 1.8 (April 28, 2017)
-------------------------------------------------
- Support for sub-directories in .pyz files (Thanks to Moritz Kroll @ Avira Operations GmbH & Co. KG)
Version 1.9 (November 29, 2017)
-------------------------------------------------
- Added support for pyinstaller 3.3
- Display the scripts which are run at entry (Thanks to Michael Gillespie @ malwarehunterteam for the feature request)
"""
from __future__ import print_function
import os
import struct
import marshal
import zlib
import sys
import imp
import types
from uuid import uuid4 as uniquename
class CTOCEntry:
  def __init__(self, position, cmprsdDataSize, uncmprsdDataSize, cmprsFlag, typeCmprsData, name):
    self.position = position
    self.cmprsdDataSize = cmprsdDataSize
    self.uncmprsdDataSize = uncmprsdDataSize
    self.cmprsFlag = cmprsFlag
    self.typeCmprsData = typeCmprsData
    self.name = name
class PyInstArchive:
  PYINST20_COOKIE_SIZE = 24      # For pyinstaller 2.0
  PYINST21_COOKIE_SIZE = 24 + 64   # For pyinstaller 2.1+
  MAGIC = b'MEI\014\013\012\013\016' # Magic number which identifies pyinstaller
  def __init__(self, path):
    self.filePath = path
  def open(self):
    try:
      self.fPtr = open(self.filePath, 'rb')
      self.fileSize = os.stat(self.filePath).st_size
    except:
      print('[*] Error: Could not open {0}'.format(self.filePath))
      return False
    return True
  def close(self):
    try:
      self.fPtr.close()
    except:
      pass
  def checkFile(self):
    print('[*] Processing {0}'.format(self.filePath))
    # Check if it is a 2.0 archive
    self.fPtr.seek(self.fileSize - self.PYINST20_COOKIE_SIZE, os.SEEK_SET)
    magicFromFile = self.fPtr.read(len(self.MAGIC))
    if magicFromFile == self.MAGIC:
      self.pyinstVer = 20   # pyinstaller 2.0
      print('[*] Pyinstaller version: 2.0')
      return True
    # Check for pyinstaller 2.1+ before bailing out
    self.fPtr.seek(self.fileSize - self.PYINST21_COOKIE_SIZE, os.SEEK_SET)
    magicFromFile = self.fPtr.read(len(self.MAGIC))
    if magicFromFile == self.MAGIC:
      print('[*] Pyinstaller version: 2.1+')
      self.pyinstVer = 21   # pyinstaller 2.1+
      return True
    print('[*] Error : Unsupported pyinstaller version or not a pyinstaller archive')
    return False
  def getCArchiveInfo(self):
    try:
      if self.pyinstVer == 20:
        self.fPtr.seek(self.fileSize - self.PYINST20_COOKIE_SIZE, os.SEEK_SET)
        # Read CArchive cookie
        (magic, lengthofPackage, toc, tocLen, self.pyver) = \
        struct.unpack('!8siiii', self.fPtr.read(self.PYINST20_COOKIE_SIZE))
      elif self.pyinstVer == 21:
        self.fPtr.seek(self.fileSize - self.PYINST21_COOKIE_SIZE, os.SEEK_SET)
        # Read CArchive cookie
        (magic, lengthofPackage, toc, tocLen, self.pyver, pylibname) = \
        struct.unpack('!8siiii64s', self.fPtr.read(self.PYINST21_COOKIE_SIZE))
    except:
      print('[*] Error : The file is not a pyinstaller archive')
      return False
    print('[*] Python version: {0}'.format(self.pyver))
    # Overlay is the data appended at the end of the PE
    self.overlaySize = lengthofPackage
    self.overlayPos = self.fileSize - self.overlaySize
    self.tableOfContentsPos = self.overlayPos + toc
    self.tableOfContentsSize = tocLen
    print('[*] Length of package: {0} bytes'.format(self.overlaySize))
    return True
  def parseTOC(self):
    # Go to the table of contents
    self.fPtr.seek(self.tableOfContentsPos, os.SEEK_SET)
    self.tocList = []
    parsedLen = 0
    # Parse table of contents
    while parsedLen < self.tableOfContentsSize:
      (entrySize, ) = struct.unpack('!i', self.fPtr.read(4))
      nameLen = struct.calcsize('!iiiiBc')
      (entryPos, cmprsdDataSize, uncmprsdDataSize, cmprsFlag, typeCmprsData, name) = \
      struct.unpack( \
        '!iiiBc{0}s'.format(entrySize - nameLen), \
        self.fPtr.read(entrySize - 4))
      name = name.decode('utf-8').rstrip('\0')
      if len(name) == 0:
        name = str(uniquename())
        print('[!] Warning: Found an unamed file in CArchive. Using random name {0}'.format(name))
      self.tocList.append( \
                CTOCEntry(           \
                  self.overlayPos + entryPos, \
                  cmprsdDataSize,       \
                  uncmprsdDataSize,      \
                  cmprsFlag,         \
                  typeCmprsData,       \
                  name            \
                ))
      parsedLen += entrySize
    print('[*] Found {0} files in CArchive'.format(len(self.tocList)))
  def extractFiles(self):
    print('[*] Beginning extraction...please standby')
    extractionDir = os.path.join(os.getcwd(), os.path.basename(self.filePath) + '_extracted')
    if not os.path.exists(extractionDir):
      os.mkdir(extractionDir)
    os.chdir(extractionDir)
    for entry in self.tocList:
      basePath = os.path.dirname(entry.name)
      if basePath != '':
        # Check if path exists, create if not
        if not os.path.exists(basePath):
          os.makedirs(basePath)
      self.fPtr.seek(entry.position, os.SEEK_SET)
      data = self.fPtr.read(entry.cmprsdDataSize)
      if entry.cmprsFlag == 1:
        data = zlib.decompress(data)
        # Malware may tamper with the uncompressed size
        # Comment out the assertion in such a case
        assert len(data) == entry.uncmprsdDataSize # Sanity Check
      with open(entry.name, 'wb') as f:
        f.write(data)
      if entry.typeCmprsData == b's':
        print('[+] Possible entry point: {0}'.format(entry.name))
      elif entry.typeCmprsData == b'z' or entry.typeCmprsData == b'Z':
        self._extractPyz(entry.name)
  def _extractPyz(self, name):
    dirName = name + '_extracted'
    # Create a directory for the contents of the pyz
    if not os.path.exists(dirName):
      os.mkdir(dirName)
    with open(name, 'rb') as f:
      pyzMagic = f.read(4)
      assert pyzMagic == b'PYZ\0' # Sanity Check
      pycHeader = f.read(4) # Python magic value
      if imp.get_magic() != pycHeader:
        print('[!] Warning: The script is running in a different python version than the one used to build the executable')
        print('  Run this script in Python{0} to prevent extraction errors(if any) during unmarshalling'.format(self.pyver))
      (tocPosition, ) = struct.unpack('!i', f.read(4))
      f.seek(tocPosition, os.SEEK_SET)
      try:
        toc = marshal.load(f)
      except:
        print('[!] Unmarshalling FAILED. Cannot extract {0}. Extracting remaining files.'.format(name))
        return
      print('[*] Found {0} files in PYZ archive'.format(len(toc)))
      # From pyinstaller 3.1+ toc is a list of tuples
      if type(toc) == list:
        toc = dict(toc)
      for key in toc.keys():
        (ispkg, pos, length) = toc[key]
        f.seek(pos, os.SEEK_SET)
        fileName = key
        try:
          # for Python > 3.3 some keys are bytes object some are str object
          fileName = key.decode('utf-8')
        except:
          pass
        # Make sure destination directory exists, ensuring we keep inside dirName
        destName = os.path.join(dirName, fileName.replace("..", "__"))
        destDirName = os.path.dirname(destName)
        if not os.path.exists(destDirName):
          os.makedirs(destDirName)
        try:
          data = f.read(length)
          data = zlib.decompress(data)
        except:
          print('[!] Error: Failed to decompress {0}, probably encrypted. Extracting as is.'.format(fileName))
          open(destName + '.pyc.encrypted', 'wb').write(data)
          continue
        with open(destName + '.pyc', 'wb') as pycFile:
          pycFile.write(pycHeader)   # Write pyc magic
          pycFile.write(b'\0' * 4)   # Write timestamp
          if self.pyver >= 33:
            pycFile.write(b'\0' * 4) # Size parameter added in Python 3.3
          pycFile.write(data)
def main():
  if len(sys.argv) < 2:
    print('[*] Usage: pyinstxtractor.py <filename>')
  else:
    arch = PyInstArchive(sys.argv[1])
    if arch.open():
      if arch.checkFile():
        if arch.getCArchiveInfo():
          arch.parseTOC()
          arch.extractFiles()
          arch.close()
          print('[*] Successfully extracted pyinstaller archive: {0}'.format(sys.argv[1]))
          print('')
          print('You can now use a python decompiler on the pyc files within the extracted directory')
          return
      arch.close()
if __name__ == '__main__':
  main()

Summarize

The above is the site to introduce python decompilation exe file for py file example code, I hope to help you, if you have any questions welcome to leave me a message, this site will reply to you in time!


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