Nu plugin binary reader

A nushell plugin to read binary data

     ┌───────┐
     │  png  ├────────────────────┐
     └───────┘                    │
                                  │
      ┌─────┐             ┌───────▼─────────────┐
      │ ttf ├────────────►│                     │
      └─────┘             │      Nushell        ├─────►Structured data
                          │                     │
     ┌───────┐            │                     │
     │  bmp  ├───────────►└─────────────────────┘
     └───────┘                   ▲
                                 │
    ┌─────────┐                  │
    │   gif   ├──────────────────┘
    └─────────┘
        ...

Screenshots

Parsing png and ttf

Download lib and parse binary

Prerequisite

1. nushell, It's a nushell plugin, so you need it.
2. python3.6+

Usage

1. register the plugin to nushell

register nu_plugin_bin_reader.py

It will introduce a new command: from-binary. So you can play with it You can just do it once.

2. fetch libs

There is fetcher.nu to help you download binary reader. You can do something like this:

> use fetcher.nu
> fetcher fetch-lib png

It will download "png" binary parser for you.

3. parse relative binary file Take png file as example, you can do the following to get capture.png information.

open capture.png | from-binary png

Then it will output the following:

╭───────────┬───────────────────────────────────╮
│ magic     │ [137, 80, 78, 71, 13, 10, 26, 10] │
│ ihdr_len  │ 13                                │
│ ihdr_type │ [73, 72, 68, 82]                  │
│ ihdr      │ {record 7 fields}                 │
│ ihdr_crc  │ [179, 17, 228, 177]               │
│ chunks    │ [table 9 rows]                    │
╰───────────┴───────────────────────────────────╯

Ok, what if you want to get the size of png file, you need to know it's stored inside ihdr, so you just need to get ihdr.

open capture.png | from-binary png | get ihdr

So it will output the following:

╭────────────────────┬───────────────────╮
│ width              │ 1470              │
│ height             │ 728               │
│ bit_depth          │ 8                 │
│ color_type         │ {record 0 fields} │
│ compression_method │ 0                 │
│ filter_method      │ 0                 │
│ interlace_method   │ 0                 │
╰────────────────────┴───────────────────╯

Note

The kaitaistruct.py is just a copy of kaitai struct python runtime, put it directly here, so we don't need extra requirements. DON'T CHANGE IT.

reader/*.py are just a copy of auto-generated parser, DON'T CHANGE IT.

To keep the repo as small as possible, it doesn't provide all parsing libs by default, and just provide png, ttf for showcase.

If you need all parsing lib, just do the following:

use fetcher.nu
fetcher fetch-all-libs

It'll take several minutes to download all binary parsing libs which exists in kaitai gallery.

For more references

• Nushell plugin system
• kaitai struct