[SSSD-users] unexpected owner for credentials
I’m trying to support an odd configuration.
We have an IPA system, which is used in the normal way for systems run by staff. But we
have hundreds of systems run by faculty and grad students. I’d like to encourage them to
integrate with our system. However their usernames and UIDs don’t typically match ours. I
don’t think there’s much I can do about usernames. But I’d at least like to survive
differing UIDs. Kerberos and even NFS V4 don’t care about UIDs.
So I set up sssd pointing to IPA, with access_provider = deny (meaning only people
accepted by pam_unix can login), and nsswitch.conf having “files sss." If a user
logins in with the Kerberos password they’re logged in correctly, but they can’t access
their own Kerberos credentials.
Their logged in UID is the one in /etc/passwd, because login correctly obeys nsswitch. But
their Kerberos credentials are for the UID in IPA.
I can change id_provider to proxy/files. But then the sss nsswitch map doesn’t work. I
need to get groups from IPA in order to interpret groups on our Netapp. I’d like to get
users from IPA when there isn’t an entry in /etc/passwd, so that ls -l on the Netapp can
interpret user names.
So what I’d like is that when sssd creates Kerberos credentials, it uses the same user
that login is going to use, i.e. that it obeys nsswitch. Is this a reasonable
expectation?
Going further, I’d like a way to do username mapping that will work with both sssd and
Kerberos. One approach would be to pay attention to the username map in /etc/krb5.conf or
idmapd.conf, since I’d have to put the mapping in both (I think).