Block diagram
This page hosts a formal specification of cpio archive, old binary variant, little-endian using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
meta:
id: cpio_old_le
title: cpio archive, old binary variant, little-endian
file-extension: cpio
xref:
forensicswiki: cpio
justsolve: Cpio
mime: application/x-cpio
pronom: fmt/635
wikidata: Q285296
license: CC0-1.0
endian: le
seq:
- id: files
type: file
repeat: eos
types:
file:
seq:
- id: header
type: file_header
- id: path_name
size: header.path_name_size - 1
- id: string_terminator
contents: [0x00]
- id: path_name_padding
contents: [0x00]
if: header.path_name_size % 2 == 1
- id: file_data
size: header.file_size.value
- id: file_data_padding
contents: [0x00]
if: header.file_size.value % 2 == 1
- id: end_of_file_padding
size-eos: true
if: path_name == [0x54, 0x52, 0x41, 0x49, 0x4c, 0x45, 0x52, 0x21, 0x21, 0x21] and header.file_size.value == 0
file_header:
seq:
- id: magic
contents: [0xC7, 0x71]
- id: device_number
type: u2
- id: inode_number
type: u2
- id: mode
type: u2
- id: user_id
type: u2
- id: group_id
type: u2
- id: number_of_links
type: u2
- id: r_device_number
type: u2
- id: modification_time
type: four_byte_unsigned_integer
- id: path_name_size
type: u2
- id: file_size
type: four_byte_unsigned_integer
four_byte_unsigned_integer:
seq:
- id: most_significant_bits
type: u2
- id: least_significant_bits
type: u2
instances:
value:
value: least_significant_bits + (most_significant_bits << 16)