OpenSSH, PAM and kerberos

[Slawa Olhovchenkov]

On Tue, Sep 03, 2013 at 01:27:04PM +0200, Dag-Erling Sm??rgrav wrote:

> Slawa Olhovchenkov <slw at zxy.spb.ru> writes:
> > Dag-Erling Sm??rgrav <des at des.no> writes:
> > > Slawa Olhovchenkov <slw at zxy.spb.ru> writes:
> > > > And how in this case can be resolved situation with PAM credentials
> > > > (Kerberos credentials in may case)?
> > > The application does not need them.
> > I need them. I need single sign-on, I need enter password only once,
> > at login time and use this credentials to login to other host and use
> > Kerberosed NFS w/o entering password.
> 
> The application does not need pam_krb5's temporary credential cache.  It
> is only used internally.  Single sign-on is implemented by storing your
> credentials in a *permanent* credential cache (either a file or KCM)
> which is independent of the PAM session and the application.  The
> location of the permanent credential cache is exported to the
> application through the KRB5CCNAME environment variable.

Yes, but content of credential cache got at time pam_authenticate().
And this content (size, structure and links to other objects)
invisible outside PAM. Application (and authenticate daemon) can't be
extract this for transfer and (in general case) can't be know about
necessary acts (write to file? what file? set enviroment?) -- all this
activity do internals by PAM modules -- one bu pam_krb5, other by
pam_opie and pam_unix. Also, authenticate daemon (in case authenticate
daemon call pam_setcred) can't be know what need to transfer (chaneged UID?
new enviroment? deleted enviroment?)