Red Hat Bugzilla – Bug 18889
pam does not accept HPUX passwords shared over nis
Last modified: 2007-03-26 23:36:27 EDT
The Red Hat Linux 7.0 pam authentification does not accept HPUX passwords
over nis. HPUX adds the aging information behind the password.
Example: after the comma is the aging information (A/3N)
...> ypcat passwd | grep dornjt
(BTW this is not my real password ;-)
Copying the old configuration from Red Hat 6.2 fixes the problem.
Without a standard fix or the information that using the old config files
we cannot upgrade to Red Hat 7.0 which we at our university (a pool with 70
for our Computer Graphics Department (we need the OpenGL support for NVIDIA
I would say that 7.0 is correct in rejecting the broken HP NIS entries. I'm not
aware of any reason that using the older PAM module should have any security
implications. Obviously you need to watch for future 6.2 errata to the PAM
modules if you do this.
Im leaving this bug open, its not clear that 'HP/UX is wrong' is sufficient of
an answer and we probably should look at teaching PAM about this paticular HP
> I would say that 7.0 is correct in rejecting the broken HP NIS entries.
I'm sorry, but your definitly wrong. The HPUX passwords is a documented feature
of nis on a HPUX machine. This is _not_ a bug on the HPUX side.
It used to work with Red Hat Linux 6.2. You changed the behavior on RH 7. So
please do me a favor and fix it instead of arguing that HPUX is broken.
Please check if the pam-0.72-32 packages in http://people.redhat.com/nalin/test/
fix this problem for you. A workaround has been added to the pam_unix module to
ignore the aging information.
Hi, I've been hauting some other bugs on our running system so I wasn't able to
test, sorry it took so long.
Yes it seems to work fine but in my opinion the aging information should not be
ignored. A collegue figured out the encoding for the HPUX aging information I
going top post it this afternoon (hopefully).
Hi again ;-)
I got the aging information encoding. It's four byte
1st byte: vality duration (in weeks)
2nd byte: minimum time untill a change is allowed (also in weeks)
3rd an 4th byte: date last changed (in weeks since the 1.1.1970)
The encoding for the numbers is:
. => 0
/ => 1
0 => 2
9 => 11
A => 12
Z => 37
a => 38
z => 63
The last change date is (in  is the byte):
That makes something like 4095 weeks or approx. 78 years so there will be a
y2048 problem in HPUX :-)
It would be a good extension to the pam modules to recognize the expiration date
on the linux clients :-)
The problem with this method of encoding the information is that pam_unix
expects aging information to be returned when it calls getspnam(), which I doubt
is smart enough to parse this out of the user's password field.
- who's responsible for the pam modules? (who to send a patch when availible -
might take some time)
since this did not work before with the red hat 6.2 it isn't this important :-)
You can attach a patch directly to the bug report if you like.
If you feel this problem is fixed now however, or no longer relevant
to you, feel free to close the report.