Look up ASNs
704fb84c — Blake Williams 4 months ago
ASN data 20240123
e4a200d2 — Blake Williams 6 months ago
Update embedded data
79b3eab7 — Blake Williams 9 months ago
Clarify the README a bit


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You can also use your local clone with git send-email.

#🚫🐎 ASNine 🐎🚫

Look up ASNs. Can be used as a library or a CLI.

Comes with (possibly out of date) versions of the ASN database from APNIC embedded:

Or you can download and parse new versions yourself with asn.ParseReference and asn.ParseMappings.

Install the CLI:

go install go.shabbyrobe.org/asnine/cmd/asnine@latest

You can look up individual IPs like so:

asnine lookup

But it's really slow to do it this way because the data is slow to parse and I don't have a good intermediate format yet.

There's also a scan mode that works with stdin, and is most useful with a streaming pipe input:

$ </some/log jq -r .ipAddress | asnine scan -

scan can also be used with rlwrap to create a cheap interactive shell. You can get rlwrap from homebrew, apt, or where all good action toys are sold. (NOTE: There may be a delay before the first input produces an output):

$ rlwrap -S 'ip> ' asnine scan -
{"success":true,"ip":"", ...}
{"success":true,"ip":"", ...}

If you're really adventurous, there's a crap linewise TCP server you can use like so:

go run asnine serve

Then you can use rlwrap, just as with scan, from another terminal, and it'll behave pretty much the same way:

$ rlwrap -S 'ip> ' nc 9876

#Expectation management

This is a tool I hack on for my own amusement in an ad-hoc fashion. No stability guarantees are made, the code is not guaranteed to work, and anything may be changed, renamed or removed at any time as I see fit.

If you wish to use any of this, I strongly recommend you copy-paste pieces as-needed (including tests and license/attribution) into your own project, or fork it for your own purposes.

Bug reports are welcome, feature requests discouraged, and code contributions will not be accepted.


asnine is Copyright Blake Williams code@shabbyrobe.org 2023. It is licensed under a 3-clause BSD license.