call back

[Eelco van Asperen]

in article <3208 at edm.UUCP>, steve at edm.UUCP (Stephen Samuel) says:
> 1) if you have the 'ct' command, you can use it to dial out and start
> up a gety task, you would then need a command like;

This is what I *intended* to mention in my previous posting; unforunately,
my brain was disconnected from my fingers for a few seconds and I typed
'cu (call Unix)'. Oops.

>  One serious problem with the shell script is that it leaves your
>  system vulnerable to someone who manages to dial in between your
>  hanging up and the system dialing out (you'd have a shell running
>  at that point).

If you invoke the standard getty from a shell that checks for a lock-
file, you could dial-in, give the command to call back, which creates
the lock, and logout.
After the logout, the getty-shell notices the lock and starts to dial
the number you requested. When a connection has been established,
it forks off a getty to enable you to login.
If this getty terminates, ie. you have logged out, it removes the
lockfile, terminates the connection and restarts a getty to enable
future logins.
By taking the tty- and locking-routines from C-kermit, it should not
be too hard to produce such a program. If I feel like it, I might
even give it a go someday.


-- 
Eelco van Asperen.		
uucp:        evas at eurtrx / mcvax!eurtrx!evas	#include <inews/filler.h>
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