Andes Firmware Image layout as seen in MT76 Wifi Chipsets: Python parsing library

Firmware image found with MediaTek MT76xx wifi chipsets.

Application

Firmware Image wifi chipset

KS implementation details

License: CC0-1.0

This page hosts a formal specification of Andes Firmware Image layout as seen in MT76 Wifi Chipsets 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 = AndesFirmware.from_file("path/to/local/file.bin")

Or parse structure from a bytes:

from kaitaistruct import KaitaiStream, BytesIO

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

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

data.image_header # => get image header

Python source code to parse Andes Firmware Image layout as seen in MT76 Wifi Chipsets

andes_firmware.py

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

import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO


if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
    raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))

class AndesFirmware(KaitaiStruct):
    """Firmware image found with MediaTek MT76xx wifi chipsets."""
    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._raw_image_header = self._io.read_bytes(32)
        _io__raw_image_header = KaitaiStream(BytesIO(self._raw_image_header))
        self.image_header = AndesFirmware.ImageHeader(_io__raw_image_header, self, self._root)
        self.ilm = self._io.read_bytes(self.image_header.ilm_len)
        self.dlm = self._io.read_bytes(self.image_header.dlm_len)

    class ImageHeader(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.ilm_len = self._io.read_u4le()
            self.dlm_len = self._io.read_u4le()
            self.fw_ver = self._io.read_u2le()
            self.build_ver = self._io.read_u2le()
            self.extra = self._io.read_u4le()
            self.build_time = (self._io.read_bytes(16)).decode(u"UTF-8")