Identify one card from another

[akerl]

I'm using this module via https://github.com/yawn/ykoath/blob/master/ykoath.go and running into something I'd like to implement.

Right now, if I have multiple yubikeys plugged in, they get the same reader name, suffixed with an integer, but the naming is based on insertion order, so it changes depending on which device I plug in first.

As an example:

package main

import (
	"fmt"

	"github.com/ebfe/scard"
)

func main() {
	context, err := scard.EstablishContext()
	if err != nil {
		panic(err)
	}

	readers, err := context.ListReaders()
	if err != nil {
		panic(err)
	}

	for _, reader := range readers {
		fmt.Println(reader)
	}
}

❯ go run ./main.go
Yubico YubiKey OTP+FIDO+CCID
Yubico YubiKey OTP+FIDO+CCID 01

I poked around a bit at this library to see if there's a way to pull a unique identifier from the attributes, but this seems like the obly attributes that the yubikey supports (thought supports is a bit of a stretch, given that most of them are blank):

Yubico YubiKey OTP+FIDO+CCID 01: AttrChannelId:
Yubico YubiKey OTP+FIDO+CCID 01: AttrIccPresence:
Yubico YubiKey OTP+FIDO+CCID 01: AttrIccInterfaceStatus:
Yubico YubiKey OTP+FIDO+CCID 01: AttrAtrString: ;��1��s�!�WYubiKey@
Yubico YubiKey OTP+FIDO+CCID 01: AttrMaxinput: �

Yubico YubiKey OTP+FIDO+CCID 01: AttrVendorName: Yubico
Yubico YubiKey OTP+FIDO+CCID 01: AttrVendorIfdVersion: C
Yubico YubiKey OTP+FIDO+CCID 01: AttrVendorIfdSerialNo:

Are you aware of a way I can differentiate between the smartcards in a deterministic way?