New subject: Cant get new TGT after kdestroy on gdm login with smartcard.

13 Feb 2019


      I am having problems consistently getting a TGT after logging in via GDM
with smartcard. On first login it normally works, but if I do a 'kdestroy'
and then logout of my gnome session, I don't get a new TGT when I login to
a new session. Instead, the root user has a TGT for my AD user:
[a001329@c20693 ~]$ klist
klist: Credentials cache 'KCM:60483' not found
[root@c20693 ~]# klist
Ticket cache: KCM:0:63363
Default principal: a001329@EXAMPLE.COM
Valid starting       Expires              Service principal
2019-02-13 15:11:38  2019-02-14 01:11:33  krbtgt/EXAMPLE.com@EXAMPLE.com
    renew until 2019-02-20 15:11:33
A wild guess is that krb5-pkinit works by letting the root user get a TGT
for my user and then transfer that cache to my user, or something? In my
case that transfer does not happen if I previously performed a kdestroy.
From krb5_child.log:
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]]
[sss_get_ccache_name_for_principal] (0x4000): Location: [KCM:]
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]]
[sss_get_ccache_name_for_principal] (0x4000): tmp_ccname: [KCM:0:71555]
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [create_ccache]
(0x4000): Initializing ccache of type [KCM]
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [create_ccache]
(0x4000): CC supports switch
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [create_ccache]
(0x4000): returning: 0
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]]
[safe_remove_old_ccache_file] (0x0400): New and old ccache file are the
same, none will be deleted.
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [k5c_send_data]
(0x0200): Received error code 0
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]]
[pack_response_packet] (0x2000): response packet size: [95]
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [k5c_send_data]
(0x4000): Response sent.
(Wed Feb 13 14:46:14 2019) [[sssd[krb5_child[12020]]]] [main] (0x0400):
krb5_child completed successfully
After a while (not sure how long) it works as expected again, presumably
after a timeout of some sort.
If I disable KCM (by removing /etc/krb5.conf.d/kcm_default_ccache) TGT
retrieval works as expected. Am I missing something or is this a bug?
Regards,
Adam