Hashcat capture file (old version): Python parsing library

Native format of Hashcat password "recovery" utility.

A sample of file for testing can be downloaded from https://web.archive.org/web/20150220013635if_/http://hashcat.net:80/misc/example_hashes/hashcat.hccap

Application

["Hashcat", "aircrack-ng"]

File extension

hccap

KS implementation details

License: Unlicense

This page hosts a formal specification of Hashcat capture file (old version) using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.

The Python runtime library can be installed from PyPI:

python3 -m pip install kaitaistruct

Code

Parse a local file and get structure in memory:

data = Hccap.from_file("path/to/local/file.hccap")

Or parse structure from a bytes:

from kaitaistruct import KaitaiStream, BytesIO

raw = b"\x00\x01\x02..."
data = Hccap(KaitaiStream(BytesIO(raw)))

After that, one can get various attributes from the structure by invoking getter methods like:

data.records # => get records

Python source code to parse Hashcat capture file (old version)

hccap.py

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

from pkg_resources import parse_version
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO


if parse_version(kaitaistruct.__version__) < parse_version('0.9'):
    raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))

class Hccap(KaitaiStruct):
    """Native format of Hashcat password "recovery" utility.
    
    A sample of file for testing can be downloaded from https://web.archive.org/web/20150220013635if_/http://hashcat.net:80/misc/example_hashes/hashcat.hccap
    
    .. seealso::
       Source - https://hashcat.net/wiki/doku.php?id=hccap
    """
    def __init__(self, _io, _parent=None, _root=None):
        self._io = _io
        self._parent = _parent
        self._root = _root if _root else self
        self._read()

    def _read(self):
        self.records = []
        i = 0
        while not self._io.is_eof():
            self.records.append(Hccap.HccapRecord(self._io, self, self._root))
            i += 1


    class HccapRecord(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            self._io = _io
            self._parent = _parent
            self._root = _root if _root else self
            self._read()

        def _read(self):
            self.essid = self._io.read_bytes(36)
            self.mac_ap = self._io.read_bytes(6)
            self.mac_station = self._io.read_bytes(6)
            self.nonce_station = self._io.read_bytes(32)
            self.nonce_ap = self._io.read_bytes(32)
            self._raw_eapol_buffer = self._io.read_bytes(256)
            _io__raw_eapol_buffer = KaitaiStream(BytesIO(self._raw_eapol_buffer))
            self.eapol_buffer = Hccap.EapolDummy(_io__raw_eapol_buffer, self, self._root)
            self.len_eapol = self._io.read_u4le()
            self.keyver = self._io.read_u4le()
            self.keymic = self._io.read_bytes(16)

        @property
        def eapol(self):
            if hasattr(self, '_m_eapol'):
                return self._m_eapol if hasattr(self, '_m_eapol') else None

            io = self.eapol_buffer._io
            _pos = io.pos()
            io.seek(0)
            self._m_eapol = io.read_bytes(self.len_eapol)
            io.seek(_pos)
            return self._m_eapol if hasattr(self, '_m_eapol') else None


    class EapolDummy(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            self._io = _io
            self._parent = _parent
            self._root = _root if _root else self
            self._read()

        def _read(self):
            pass