Support the kernel keyring as credentials cache
Submitted by Debarshi Ray
Recent versions of Fedora and Red Hat Enterprise Linux 7 use the Linux kernel keyring as the credentials cache. Running krb5-auth-dialog on such a system leads to: KrbAuthDialog-WARNING **: Unsupported cache type for 'KEYRING:persistent:1000'
Note that there isn't any notification mechanism for the kernel keyring, yet.
As an example, the Kerberos code in gnome-online-accounts (specifically, goa-identity-service) polls the keyring at 5 second intervals. Grep for monitor_credentials_cache and FALLBACK_POLLING_INTERVAL in gnome-online-accounts.