How to verify a wireguard public key?

[Nico Schottelius <nico.schottelius@ungleich.ch>]

Good morning,

I am currently extending uncloud [0] to support wireguard tunnels and
keys. At the moment it is not entirely clear how to verify that a
certain string is a valid wireguard key.

I first tried checking that it is valid base64, but not all base64
strings are valid wireguard keys.

Then I tried using `echo $key | wg pubkey && echo ok` - which seems to
check the key format, however the intended behaviour here is misused.

Does anyone have a pointer on how to reliably identify wireguard public
keys?

Is the wireguard key always 32 bytes when decoded from base64? Tests
with a number of public keys seems to indicate that.

Best regards,

Nico


[0] https://code.ungleich.ch/uncloud/uncloud

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