takproto 2.0.0

A Python module to encode & decode 'TAK Protocol Payload - Version 1' Protocol Buffer based Cursor on Target (CoT) messages.

takproto: TAK Protocol Python Module

takproto is a Python module to encode & decode ‘TAK Protocol Payload - Version 1’ Protocol Buffer based Cursor on Target (CoT) messages.

From the ATAK source:

Version 1 of the TAK Protocol Payload is a Google Protocol Buffer based payload. Each Payload consists of one (and only one) atakmap::commoncommo::v1::TakMessage message which is serialized using Google protocol buffers version 3.

Source: https://github.com/deptofdefense/AndroidTacticalAssaultKit-CIV/blob/master/commoncommo/core/impl/protobuf/protocol.txt

takproto is a fork & complete re-write of @dB-SPL’s takprotobuf. Absolute credit goes to them for their initial implementation.

Notable differences between the original takprotobuf & this module takproto:

1. Rebuild proto files using Protocol Buffers v21.

2. Added support for encoding & decoding plain XML, Mesh & Stream TAK Protocol formats.

3. Remove dependency on untangle module, allowing compatibility with Python 3.6 through 3.10. Unfortunately many single-board computers (i.e. Raspberry Pi) still ship with Python 3.6, this change allows takproto to run on those systems.

4. Added xmlDetails detection for supporting undefined Protobuf elements in XML.

5. > 90% test coverage with new Unit Tests.

6. PEP-8 & Black style, linting, documentation & formatting of code.

As much as possible @db-SPL’s licensing terms were honored in this fork.

Usage

The takproto module exports two functions:

xml2proto()

Given a string which contains either a CoT message in XML or the path to an XML file containing a CoT message, the function xml2proto() will return a bytearray containing the binary protobuf:

import takproto

cot = """<?xml version='1.0' encoding='UTF-8' standalone='yes'?>
<event version='2.0' uid='aa0b0312-b5cd-4c2c-bbbc-9c4c70216261' type='a-f-G-E-V-C' time='2020-02-08T18:10:44.000Z' start='2020-02-08T18:10:44.000Z' stale='2020-02-08T18:11:11.000Z' how='h-e'>
    <point lat='43.97957317' lon='-66.07737696' hae='26.767999' ce='9999999.0' le='9999999.0' />
    <detail>
        <uid Droid='Eliopoli HQ'/>
        <contact callsign='Eliopoli HQ' endpoint='192.168.1.10:4242:tcp'/>
        <__group name='Yellow' role='HQ'/><status battery='100'/>
        <takv platform='WinTAK-CIV' device='LENOVO 20QV0007US' os='Microsoft Windows 10 Home' version='1.10.0.137'/>
        <track speed='0.00000000' course='0.00000000'/>
    </detail>
</event>
"""

buf = takproto.xml2proto(cot)
print(buf)

Would return the CoT XML encoded as TAK Protocol Version 1 Mesh:

bytearray(b'\xbf\x01\xbf\x12\xff\x01\n\x0ba-f-G-E-V-C*$aa0b0312-b5cd-4c2c-bbbc-9c4c702162610\xa0\xa2\xc7\xb8\x82.8\xa0\xa2\xc7\xb8\x82.@\x98\xf5\xc8\xb8\x82.J\x03h-eQ3\x98T\xa7b\xfdE@Y}*~\xbe\xf3\x84P\xc0aW\\\x1c\x95\x9b\xc4:@i\x00\x00\x00\xe0\xcf\x12cAq\x00\x00\x00\xe0\xcf\x12cAz\x82\x01\x12$\n\x15192.168.1.10:4242:tcp\x12\x0bEliopoli HQ\x1a\x0c\n\x06Yellow\x12\x02HQ*\x02\x08d2F\n\x11LENOVO 20QV0007US\x12\nWinTAK-CIV\x1a\x19Microsoft Windows 10 Home"\n1.10.0.137:\x00')

Additionally, calling xml2proto with the takproto.TAKProtoVer.STREAM flag would return a stream-ready protobuf:

buf = takproto.xml2proto(cot, takproto.TAKProtoVer.STREAM)
print(buf)

Would return the CoT XML encoded as TAK Protocol Version 1 Stream:

bytearray(b'\xbf\x9f\x02\x12\xff\x01\n\x0ba-f-G-E-V-C*$aa0b0312-b5cd-4c2c-bbbc-9c4c702162610\xa0\xa2\xc7\xb8\x82.8\xa0\xa2\xc7\xb8\x82.@\x98\xf5\xc8\xb8\x82.J\x03h-eQ3\x98T\xa7b\xfdE@Y}*~\xbe\xf3\x84P\xc0aW\\\x1c\x95\x9b\xc4:@i\x00\x00\x00\xe0\xcf\x12cAq\x00\x00\x00\xe0\xcf\x12cAz\x82\x01\x12$\n\x15192.168.1.10:4242:tcp\x12\x0bEliopoli HQ\x1a\x0c\n\x06Yellow\x12\x02HQ*\x02\x08d2F\n\x11LENOVO 20QV0007US\x12\nWinTAK-CIV\x1a\x19Microsoft Windows 10 Home"\n1.10.0.137:\x00')

parse_proto()

Given a bytearray containing a version 1 protobuf, parse_proto() will return an instance of the protobuf class. You can then access the contents as an object:

import takproto

pb = bytearray(b'\xbf\x01\xbf\x12\xff\x01\n\x0ba-f-G-E-V-C*$aa0b0312-b5cd-4c2c-bbbc-9c4c702162610\xa0\xa2\xc7\xb8\x82.8\xa0\xa2\xc7\xb8\x82.@\x98\xf5\xc8\xb8\x82.J\x03h-eQ3\x98T\xa7b\xfdE@Y}*~\xbe\xf3\x84P\xc0aW\\\x1c\x95\x9b\xc4:@i\x00\x00\x00\xe0\xcf\x12cAq\x00\x00\x00\xe0\xcf\x12cAz\x82\x01\x12$\n\x15192.168.1.10:4242:tcp\x12\x0bEliopoli HQ\x1a\x0c\n\x06Yellow\x12\x02HQ*\x02\x08d2F\n\x11LENOVO 20QV0007US\x12\nWinTAK-CIV\x1a\x19Microsoft Windows 10 Home"\n1.10.0.137:\x00')

cot = parse_proto(pb)

This method of calling parse_proto would return an object containing the data from the protobuf. If you were to print(cot), you would see:

cotEvent {
    type: "a-f-G-E-V-C"
    uid: "aa0b0312-b5cd-4c2c-bbbc-9c4c70216261"
    sendTime: 1581203444000
    startTime: 1581203444000
    staleTime: 1581203471000
    how: "h-e"
    lat: 43.97957317
    lon: -66.07737696
    hae: 26.767999
    ce: 9999999.0
    le: 9999999.0
    detail {
        contact {
        endpoint: "192.168.1.10:4242:tcp"
        callsign: "Eliopoli HQ"
        }
        group {
        name: "Yellow"
        role: "HQ"
        }
        status {
        battery: 100
        }
        takv {
        device: "LENOVO 20QV0007US"
        platform: "WinTAK-CIV"
        os: "Microsoft Windows 10 Home"
        version: "1.10.0.137"
        }
        track {
        }
    }
}

Object attributes can be accessed by calling them in a Pythonic manner:

print(cot.cotEvent.detail.contact.callsign)
"Eliopoli HQ"

Additional Examples

For additional examples using this module, see the tests/ directory.

What’s the difference between the TAK Protocol formats?

Originally the TAK Products spoke Cursor on Target (CoT) encoded as plain XML. Later versions of the TAK Products added support for sending CoT as Google Protobuf, which TPC named ‘TAK Protocol Version 1’.

Out of the box, TAK Products such as ATAK and WinTAK configured for ‘Mesh SA’ will send TAK Protocol Version 1 Mesh formatted CoT. This format utizes a static payload header of the format 191 1 191 <payload>.

TAK Products configured for connecting to a TAK Server will send TAK Protocol Version 1 Stream formatted CoT. This format utizes a dynamic payload header of the format 191 <varint payload length> <payload>. This header format is required for specifying the size of the payload within the TCP packet.

The takproto module supports encoding and decoding all 3 formats of CoT messages.

Source

Github: https://github.com/snstac/takproto

Authors

• Greg Albrecht https://www.snstac.com/

• Delta Bravo-15 https://github.com/db-SPL

Copyright

• Copyright 2023 Sensors & Signals LLC

• Copyright 2020 Delta Bravo-15 <[e-mail]>

Style

Python Black, otherwise Google, then PEP-8.

License

Copyright 2023 Sensors & Signals LLC

Copyright 2020 Delta Bravo-15 <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.