topic Re: Enforcing shell timeout? in Operating System - HP-UX

Enforcing shell timeout?

Alex Georgiev — Tue, 24 Jul 2007 04:05:06 GMT

Does anyone have a creative & elegant way of enforcing shell timeouts for users?

Currently I'm doing it by executing 'typeset -r TMOUT=' in the /etc/profile. This prevents the user from unsetting the TMOUT variable, or from editing their own .profile and changing it.

Unfortunately it also prevents them from specifying a shorter timeout, if they wish to do so. Plus, it seems to conflict with certain apps that try to modify it.

Re: Enforcing shell timeout?

Peter Nikitka — Tue, 24 Jul 2007 07:18:30 GMT

Hi,

you'll have to use some scripting.
I would look for an optional config file ~/.tmout
where the user could specify something like
TMOUT=nnn

and in /etc/profile use something like this:
tmout_default=1024
if [ -s $HOME/.tmout ]
then
usrtmout=$(awk -F= '$1=="TMOUT" {print $2}' $HOME/.tmout)
[ "$usrtmout" -gt $tmout_default ] && unset usrtmout
if
typeset -r TMOUT=${usrtmout:-$tmout_default}

mfG Peter

Re: Enforcing shell timeout?

Alex Georgiev — Tue, 24 Jul 2007 18:49:03 GMT

Yes, that's a good idea. A ~/.tmout would work.

Any other ideas for how to do that?

P.S. Something that went though my mind is to compile the shell from source, but edit the source code beforehand and hard code a maximum value in there. The problem with that is that I might only be able to do it for bash & tcsh, since I'm not sure if I can find the source for the HP-UX ksh & dtksh.

Also, there's alway the possibility that I'll mess up and create bugs. Haven't done any serious coding in a while...

Re: Enforcing shell timeout?

James R. Ferguson — Tue, 24 Jul 2007 18:59:09 GMT

Hi Alex:

> Something that went though my mind is to compile the shell from source, but edit the source code beforehand and hard code a maximum value in there. The problem with that is that I might only be able to do it for bash & tcsh, since I'm not sure if I can find the source for the HP-UX ksh & dtksh.

You won't be able to obtain the source for HP-UX released versions.

That aside, I've "been-there-done-that" in "another life" many years ago. As a then mainframe systems programmer I had source code and was used to developing patches as work-arounds and customizations. The problem was always re-engineering the patch and re-certifying it as new releases and vendor-supplied enhancements appeared.

Put your creative efforts to use in another way. Peter's suggestion is a good one.

Regards!

...JRF...

Re: Enforcing shell timeout?

Peter Nikitka — Wed, 25 Jul 2007 01:49:23 GMT

Hi,

additionally you should check the setting of a user-timeout not being zero: This could mean NO timeout in some shells!

mfG Peter

PS: Of course you could permit this as a 'feature'...