🚀 go-pugleaf

In article <1992Nov22.005737.15056@odin.corp.sgi.com> toms@ymp.esd.sgi.com (Tom Stephenson) writes:
>In article <Nov18.202206.59161@yuma.ACNS.ColoState.EDU>, hallch@CS.ColoState.EDU
>(christopher hall) writes:
>|> 
>|> >I am writing a TP6 program which requires the CTRL+BREAK sequence to be
>|> >disabled, as it loads in data tables and manipulates them in real time.
>|> >If CTRL+BREAK is pressed then the program bombs out and leaves the tables
>|> >in a real mess.
>|> >
>|> 
>|> I played around with this problem a few years ago.  The solution I came
>|> up with was to hook the Ctrl-Break interrupt.  I don't remember what it
>|> was (I think it was around 24h).  The only thing my interrupt was to do
>|> was return immediately to its caller.  I used this when I had to write
>|> a simple program for a teacher of mine (he wanted students to have to
>|> enter a password without being able to break of out the program).
>|> 
>|> Hope this helps.
>|> 
>|> 						Chris Hall :-)
>
>I wrote a program that allows me to have a password on my DOS machine. (I have
>teenage people at home that think they are hackers). The attached code is the

So, they haven't figured out yet what happens if one inserts a system diskette in
drive A: and press Ctrl-Alt-Del ;-) Well, than they only think they are hackers.

>You can use them in your password if you want. The entire source is available if
>you want it. I just wrote the program to emulate UNIX login process.
>
>/* Code fragment from main */
>
>		while ((c = getkeychar()) != 0x0d){
>			str[i] = c;
>			i++;
>		}
>

What happens  if  password > sizeof(str)?  Program  can exit or  crash,  quite
probably easily  interruptable in this  state. Don't get too upset  though. In
early version of AT&T UNIX one could get in any account  by  typing a password
of  maximum length  followed  by  encrypted form   of the same  password - for
exactly the same reason.   Author of  login.c used gets()  to get  a password.
Since gets doesn't check  length of input  string, it would hapily overwrite a
buffer for encrypted password.

>/*keyboard function to replace getchar() */
>
>getkeychar()
>{
>	int c;
>	inreg.h.ah = 0x07;
>	intdos (&inreg, &outreg);
>	c = outreg.h.al;
>	return (c);
>}
>
>
>
>Good Luck...

While  code above  might  be an adeqate  protection  when  dealing with (some)
teenage people, please don't use it in your password :) Hmmm, I think teaching
teenage  people to   do  something  useful  on  computer  might create  better
security...

Oleg