Files
ykfde/book/arch/recovery/add-or-replace-luks-yubikey.md
2019-01-07 17:22:08 +01:00

50 lines
2.0 KiB
Markdown

# Add or Replace LUKS YubiKey
> Create a reliable backup of your files!
This chapter describes how to add a new YubiKey or replace an YubiKey for an already encrypted LUKS volume.
You need these things:
- Your current (old) YubiKey
- Your new Yubikey
- Make sure YubiKey login is disabled
> This is only needed if you don't have the secret key of your current YubiKey
and if you want to replace it with another YubiKey or to add a second different YubiKey.
See *Replace a faulty YubiKey* if you want to initialize a new YubiKey with the secret key.
> If you are changing the passphrase of your new YubiKey, don't forget to update the *YKFDE_CHALLENGE* in `/etc/ykfde.conf`
Prepare your new YubiKey like described in chapter *03: Prepare 2nd slot* if not already done.
Display current used LUKS key slots with `cryptsetup luksDump /dev/[device 4th partition]`.
## Disable YubiKey login
If you use YubiKey login, disable it and reread chapter *07: Enable YubiKey Login* after this procedure.
To disable YubiKey login open the file `/etc/pam.d/system-auth` and comment out the line:
```
auth required pam_yubico.so mode=challenge-response chalresp_path=/var/yubico
```
Use another tty to test it.
## Add an YubiKey to LUKS
Execute `ykfde-enroll -d /dev/[device 4th partition] -s [keyslot_number] -o`. The option `-o` uses the old YubiKey
for the passphrase. Ensure your new YubiKey is inserted, you will be asked to insert the old YubiKey.
## Killing a LUKS key slot
> Ensure you are not killing a wrong key slot and make sure another key slot is working.
To test which YubiKey belongs to which key slot execute `ykfde-open -d /dev/[device 4th partition] -s [keyslot_number] -t`.
Execute `ykfde-enroll -d /dev/[device 4th partition] -s [keyslot_number] -k`. The option `-k` kills the slot.
## Replacing existing LUKS key slot
> It is recommended to add a new YubiKey to another slot and kill the other slot if all things work.
Execute `ykfde-enroll -d /dev/[device 4th partition] -s [keyslot_number] -o -c `. The option `-c` changes the key slot.