[Samba] Pam_mount not working with "sec=krb5"

buhorojo buhorojo.lcb at gmail.com
Mon Nov 2 19:35:42 UTC 2015

On 02/11/15 15:51, Ole Traupe wrote:
> Am 02.11.2015 um 15:10 schrieb buhorojo:
>> On 02/11/15 14:42, Ole Traupe wrote:
>>> Am 02.11.2015 um 13:12 schrieb buhorojo:
>>>> On 02/11/15 12:54, Ole Traupe wrote:
>>>> Why can't the user do it with his own key file?
>> Only root can perform mounts and anyway, 
> Right, sorry.
>> cifs upcall looks for a key, not a cache.
> So you just _have_ to use the keytab. Has this changed? Here it seems 
> that cache was ok in the past (see the end of the longest cited log 
> part in the middle; but there was a different problem, obviously, with 
> ownership):
> http://www.spinics.net/lists/linux-cifs/msg05290.html
>> /Jan 25 17:55:12 goto cifs.upcall: find_krb5_cc: considering 
> /tmp/krb5cc_101125/
>> /Jan 25 17:55:12 goto cifs.upcall: find_krb5_cc: /tmp/krb5cc_101125 is 
> owned by 101125, not 0/
> I mean, putting the key in the keytab looks like a security risk to me.
In what way does it appear any more of a risk than having the keys which 
you have there already? Even if someone steals the keytab, they're gonna 
be hard pressed to crack the key in the few hours before the tgt 
expires. Do you have very sensitive data maybe?
> Would be nice if you could use kerberos on the fly.

You _are_ using it on the fly.The tgt is obtained without any 
interaction on the part of the user.
> Unfortunately, I don't find such a detailed log in /var/log/messages.
>>> Also, if the user is not mounting his home share, but somebody else, 
>>> this _other_ user will be the owner of newly created files and 
>>> folders, right
>> No. With multiuser, acl and permissions are respected. If the user 
>> would normally be the owner of newly created files, then he will be 
>> also over cifs.
> Great, that sounds exactly as I would like it to be.
>> One other thing, you need a recent version of cifs utils (we don't 
>> think Centos has) 
> Mine is cifs-utils.x86_64    4.8.1-20.el6
We can confirm it works with 6.2.

>> and to make sure that you lose the -c at /etc/request-key.conf:
>> create  cifs.spnego     *       * /usr/sbin/cifs.upcall -c %k
>> HTH

More information about the samba mailing list