Mozilla ARchive file is Mozilla's own archive format to distribute software updates. Test files can be found on Mozilla's FTP site, for example:
This page hosts a formal specification of Mozilla ARchive using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing 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 kaitaistructParse a local file and get structure in memory:
data = MozillaMar.from_file("path/to/local/file.mar")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = MozillaMar(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.magic # => get magic
# 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
from enum import Enum
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 MozillaMar(KaitaiStruct):
"""Mozilla ARchive file is Mozilla's own archive format to distribute software updates.
Test files can be found on Mozilla's FTP site, for example:
<http://ftp.mozilla.org/pub/firefox/nightly/partials/>
.. seealso::
Source - https://wiki.mozilla.org/Software_Update:MAR
"""
class SignatureAlgorithms(Enum):
rsa_pkcs1_sha1 = 1
rsa_pkcs1_sha384 = 2
class BlockIdentifiers(Enum):
product_information = 1
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.magic = self._io.read_bytes(4)
if not self.magic == b"\x4D\x41\x52\x31":
raise kaitaistruct.ValidationNotEqualError(b"\x4D\x41\x52\x31", self.magic, self._io, u"/seq/0")
self.ofs_index = self._io.read_u4be()
self.file_size = self._io.read_u8be()
self.len_signatures = self._io.read_u4be()
self.signatures = []
for i in range(self.len_signatures):
self.signatures.append(MozillaMar.Signature(self._io, self, self._root))
self.len_additional_sections = self._io.read_u4be()
self.additional_sections = []
for i in range(self.len_additional_sections):
self.additional_sections.append(MozillaMar.AdditionalSection(self._io, self, self._root))
class MarIndex(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.len_index = self._io.read_u4be()
self._raw_index_entries = self._io.read_bytes(self.len_index)
_io__raw_index_entries = KaitaiStream(BytesIO(self._raw_index_entries))
self.index_entries = MozillaMar.IndexEntries(_io__raw_index_entries, self, self._root)
class IndexEntries(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.index_entry = []
i = 0
while not self._io.is_eof():
self.index_entry.append(MozillaMar.IndexEntry(self._io, self, self._root))
i += 1
class Signature(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.algorithm = KaitaiStream.resolve_enum(MozillaMar.SignatureAlgorithms, self._io.read_u4be())
self.len_signature = self._io.read_u4be()
self.signature = self._io.read_bytes(self.len_signature)
class ProductInformationBlock(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.mar_channel_name = (KaitaiStream.bytes_terminate(self._io.read_bytes(64), 0, False)).decode(u"UTF-8")
self.product_version = (KaitaiStream.bytes_terminate(self._io.read_bytes(32), 0, False)).decode(u"UTF-8")
class IndexEntry(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.ofs_content = self._io.read_u4be()
self.len_content = self._io.read_u4be()
self.flags = self._io.read_u4be()
self.file_name = (self._io.read_bytes_term(0, False, True, True)).decode(u"UTF-8")
@property
def body(self):
if hasattr(self, '_m_body'):
return self._m_body
io = self._root._io
_pos = io.pos()
io.seek(self.ofs_content)
self._m_body = io.read_bytes(self.len_content)
io.seek(_pos)
return getattr(self, '_m_body', None)
class AdditionalSection(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.len_block = self._io.read_u4be()
self.block_identifier = KaitaiStream.resolve_enum(MozillaMar.BlockIdentifiers, self._io.read_u4be())
_on = self.block_identifier
if _on == MozillaMar.BlockIdentifiers.product_information:
self._raw_bytes = self._io.read_bytes(((self.len_block - 4) - 4))
_io__raw_bytes = KaitaiStream(BytesIO(self._raw_bytes))
self.bytes = MozillaMar.ProductInformationBlock(_io__raw_bytes, self, self._root)
else:
self.bytes = self._io.read_bytes(((self.len_block - 4) - 4))
@property
def index(self):
if hasattr(self, '_m_index'):
return self._m_index
_pos = self._io.pos()
self._io.seek(self.ofs_index)
self._m_index = MozillaMar.MarIndex(self._io, self, self._root)
self._io.seek(_pos)
return getattr(self, '_m_index', None)