topic Re: shell trick? ( how to enable ENV file processing in suid script?) in Operating System - HP-UX

shell trick? ( how to enable ENV file processing in suid script?)

Sergey_27 — Wed, 24 Sep 2003 15:10:07 GMT

Hi,
Is there a way for ksh to make it ignore privileged mode? I have a suid script which has 3 lines:
#!/bin/ksh
export ENV=/home/user/env
exec ksh

and of course ksh senses that uid != ruid and sets privileged mode automatically. There seem to be nothing in the man pages which can force ksh to process ENV file.
Any suggestions?

Thanks,
Sergey.

Re: shell trick? ( how to enable ENV file processing in suid script?)

Dave La Mar — Wed, 24 Sep 2003 16:22:11 GMT

Sergey,
We get around most of the hassle of environment by including those variables necessary with the script being executed.
Doesn't exactly answer your question bu it is a solution that works for us.

Best of luck.

Regards,
dl

Re: shell trick? ( how to enable ENV file processing in suid script?)

Sergey_27 — Wed, 24 Sep 2003 16:24:02 GMT

Yes, but what I really need is having aliases loaded.

Re: shell trick? ( how to enable ENV file processing in suid script?)

Mark Grant — Thu, 25 Sep 2003 00:32:41 GMT

The way I tend to get around this is with a nasty little "C" wrapper to run the script. Make the C program setuid instead. In your case, make this call your first script. The UID and GID of the script will still be that of the user unless you also add a setuid(0) in there somewhere.something like #include main(){ execl("/mypath/myscript", "myscript",0);}

Re: shell trick? ( how to enable ENV file processing in suid script?)

RolandH — Thu, 25 Sep 2003 07:25:21 GMT

Hi Sergey,

It works for me.

My Script looks like this
#!/bin/ksh
ENV=$HOME/alias.file
export ENV
exec ksh

alias.file must have read-permissions !!

HTH
Roland

Re: shell trick? ( how to enable ENV file processing in suid script?)

Steven E. Protter — Thu, 25 Sep 2003 07:27:40 GMT

We have a line in /etc/profile or $HOME/.profile

ENV=/.kshrc

Aliases work.

SEP

Re: shell trick? ( how to enable ENV file processing in suid script?)

Sergey_27 — Thu, 25 Sep 2003 08:56:40 GMT

I guess the will explain my prolem:
man ksh
-p Disables processing of the $HOME/.profile
file and uses the file /etc/suid_profile
instead of the ENV file. This mode is on
whenever the effective uid (gid) is not
equal to the real uid (gid). Turning this
off causes the effective uid and gid to be
set to the real uid and gid.

Re: shell trick? ( how to enable ENV file processing in suid script?)

Sergey_27 — Thu, 25 Sep 2003 15:28:43 GMT

Decided not to use aliases but create functions instead and export FPATH to the child shell.

Tried c-wrapper but it still had euid!=uid

Thanks everybody.