Selectively disable login at specified line?

[John Chambers]

In article <3818 at encore.UUCP>, bzs at xenna (Barry Shein) writes:
> From: gfl at tuhold (Gerhard Fleischanderl)
> >Is it possible to notify getty(8) or login(1) of a list of users
> >who are granted login at the specified line?
> 
> Can't say I've thought it through but you might consider writing your
> own /bin/login which checks access and then execs the vendor supplied
> login (or exits.) 

Yeah, I decided the same a few years back, and in fact I did the job.
It ain't trivial.  But it's a lot of fun learning the bizarre features
(?) of the various terminal drivers on the market.

> And do be careful as a broken login can cramp a system (tho you should
> be able to fix it in single user mode as login isn't needed then.)

That's definitely true.  I tend to leave the 'console' under control of
getty until I'm really sure my program is working correctly on a new system.

> It's not ideal, but it might put it all under your control.

I think it is ideal.  I have the source to my login program, and I can
correct its problems and/or change its behavior without begging some
uncooperative vendor for help.

> I really wish AT&T would free up a few programs like login and getty
> as sources distributed with binary licenses. Some people really do
> need to add their own logic to these things for various reasons.
> 
> Maybe someday there'll be a workable GNU version of these programs.

No need; after determining that my then-employer didn't see any commercial
potential to the program, I posted it to usenet under the name 'uutty'.
Feel free.

Actually, the version I have here is somewhat better documented than the
posted version, and I've added some fun new security features.  Perhaps
I should post a new version.  I'm now going through the pangs of trying
to make it work right on SunOS; perhaps I'll replace the archived copy
with a new one when I'm convinced it is working there.  Why doesn't the
whole world just adopt the /etc/inittab version of init?  Oh, yes, there
is the question of the source license...perhaps I'll try my hand at writing
that and putting it in the public domain next.  On the other hand, maybe
I won't find the time.  Any takers?

I can hardly wait to get my hands on a 4.0 release from ATT/Sun; that should
be good for a LOT of #ifdefs in my code.

> But lo, I wander...

...and do you wonder as you wander?  [Oops; sorry 'bout 'dat ;-]

> 	-Barry Shein, ||Encore||

-- 
John Chambers <{adelie,ima,maynard,mit-eddie}!minya!{jc,root}> (617/484-6393)

[Any errors in the above are due to failures in the logic of the keyboard,
not in the fingers that did the typing.]