The documented DEFCCNAME is not the actual credential cache name

[Karl O. Pinc]

The krb5 documentation says that DEFCCNAME is /tmp/krb5cc_%{uid}. But actual credential cache file names look like: /tmp/krb5cc_127408622_wH2NwY

Setting [libdefaults] default_ccache_name to krb5cc_%{uid} in /etc/krb5.conf produces the expected credential cache file.

Unless you know this, using "mutiuser" in fstab with cifs/samba/smb mounts is nigh impossible.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: krb5-user 1.19.2-2ubuntu0.1
ProcVersionSignature: Ubuntu 5.15.0-67.74-generic 5.15.85
Uname: Linux 5.15.0-67-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.3
Architecture: amd64
CasperMD5CheckResult: pass
Date: Sat Mar 18 17:33:32 2023
InstallationDate: Installed on 2023-03-09 (9 days ago)
InstallationMedia: Ubuntu-Server 22.04.2 LTS "Jammy Jellyfish" - Release amd64 (20230217.1)
ProcEnviron:
 SHELL=/bin/bash
 LANG=en_US.UTF-8
 TERM=xterm-256color
 PATH=(custom, no user)
SourcePackage: krb5
UpgradeStatus: No upgrade log present (probably fresh install)

[Karl O. Pinc (kop)]

See also: bug #2012143 bug #2012145 bug #2012147

[Karl O. Pinc (kop)]

Hi,

Looks like the "problem" is that pam_sss is
changing the credential cache file name and
setting $KRB5CCNAME. Further information in:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1033164

Note that neither pam_sss(8) not pam_sss_gss(8) mention this,
but that is a different bug.

Regards,

Karl <email address hidden>
Free Software: "You don't pay back, you pay forward."
                 -- Robert A. Heinlein

[Sergio Durigan Junior (sergiodj)]

Thanks for taking the time to report the bug.

I am going to reassign the bug to sssd, and set its priority to low. Feel free to file a bug against Debian's sssd package (which is where this problem should be addressed, IMHO). Thanks.

[Karl O. Pinc (kop)]

On Wed, 22 Mar 2023 12:58:26 -0000
Sergio Durigan Junior <email address hidden> wrote:

> I am going to reassign the bug to sssd, and set its priority to low.
> Feel free to file a bug against Debian's sssd package (which is where
> this problem should be addressed, IMHO).

Thanks for reassigning to sssd and thanks for the help.

Regards,

Karl <email address hidden>
Free Software: "You don't pay back, you pay forward."
                 -- Robert A. Heinlein