[FAQ]: usage of yubikey via the commandline

[rubyFeedback]

Some days ago I bought a yubico key. I am on linux. Right now I don't know how to use the key.

So I found this github page and installed it via pip. That worked.

I then did this:

ykman list

The output is:

WARNING: PC/SC not available. Smart card (CCID) protocols will not function.
ERROR: Unable to list devices for connection
Security Key NFC (5.4.3) [FIDO]

So I assume the key was found but I am not sure. The WARNING and ERROR confuses
me a bit.

I am sure it is easy to understand for you guys, but right now I don't know what this means.
As other users may run into similar issues, could you perhaps add a simple FAQ somewhere
that could mention and explain such things?

For instance:

"WARNING: PC/SC not available. Smart card (CCID) protocols will not function."

I don't know if the above ^^^ is a problem or not. A FAQ entry could clarify this.

I looked at https://developers.yubico.com/yubikey-manager/ but there was no FAQ entry there.

As I am but a simple person, I need simple documentation. Thanks for reading. (Of course
the FAQ could list more things than that. Just basic usage examples, ideally in a short and
concise manner.)

[del-leehopper]

I also am a "simple person"...not associated with Yubico.

While you wait for an "expert" to reply, I will give my 2 cents:

It appears you have a "Security Key NFC". This does not support "Smart card" protocols. I think this is the reason for the "WARNING" and there is nothing to worry about (unless you needed the smart card - in which case, you need to by something like the YubiKey 5 series). You can view a comparison of features here:
https://www.yubico.com/gb/store/compare/

I agree that the warning isn't really helpful and could explain "why" smart card will not function (i.e. because you have a Security Key).

With regards to the "ERROR", I am unsure if this is related to the smart card or not and will allow an "expert" to reply.

[dainnilsson]

The Installation section of the README for this projects has a note about pcscd which also points to https://github.com/Yubico/yubikey-manager/blob/main/doc/Device_Permissions.adoc which describes the different device permissions, and for which commands they are required.

For your key specifically only FIDO is needed. The ykman list command will list all connected YubiKeys, which will require all permissions to be granted in order to be able to be exhaustive.