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From:   =?utf-8?Q?Aur=C3=A9lien?= Aptel <aaptel@suse.com>
To:     Shyam Prasad N <nspmangalore@gmail.com>
Cc:     CIFS <linux-cifs@vger.kernel.org>, samba-technical@lists.samba.org,
        Pavel Shilovsky <piastryyy@gmail.com>,
        Steve French <smfrench@gmail.com>, sribhat.msa@outlook.com
Subject: Re: [PATCH][SMB3] mount.cifs integration with PAM
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Date:   Wed, 09 Sep 2020 16:13:16 +0200
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Shyam Prasad N <nspmangalore@gmail.com> writes:
> Thoughts?

You are reaching the limits of my poor understanding of this kerberos
stuff. What is the difference between keytab and credential cache?

So IIUC you are proposing 2 ways to go about it:

a) - do PAM login in mount.cifs (which in turns calls into sssd/winbind)
   - implement umount.cifs for PAM logoff
   
b) - ignore PAM and winbind/sssd and do kinit in mount.cifs manually
   - would this requires umount.cifs as well?

I like (b) because it feels we have more control and don't require a big
external program like winbind *but* if (b) doesn't do the refreshing of
the tickets then the mount will always stop working after they
expire. This seems only useful for quick one-off mounting or
testing/debugging. Real end users will find it unreliable unless they
setup something like what winbind does essentially.

So ultimately, to me, (a) seems like the better choice. Let me know if I
misunderstood something.

Cheers,
-- 
Aurélien Aptel / SUSE Labs Samba Team
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