Reading a keystroke w/o echo

David Brooks dbrooks at penge.osf.org
Tue May 28 14:11:22 AEST 1991


Note headers: stage 1 of moving this to an appropriate group.

In article <91147.164007TGREENIN at ESOC.BITNET> TGREENIN at ESOC.BITNET writes:
>[re silly ways of obscuring passwords when you can't turn off echo]
>
>Sorry, this just won't work with Teletypes. What you should do is
>
>1. Get the user to check noone is looking.
>2. Accept the password and wind the carriage back one line
>   (if appropriate).
>3. Output a carriage return [:r] followed by sufficient characters
>   e.g. '*'s to cover the password.
>4. Return step 3, using different characters ('#','@','%' etc.)
>   until the password is totally obliterated, the paper has a hole
>   worn in it etc. (this can be quite tedious on a 110 baud TTY).
>
>Seriously, folks, this approach was used...on a
>CDC Cyber system I used to program on at the University of Manchester
>in the early 80's.

Grrmph.  Hardly what *I* would call secure.  The timesharing system at
Cambridge University (late 60's) accepted your username then typed:

******** <return> SSSSSSSS <return> HHHHHHHH <return>

and THEN you entered the password.  Most effective, especially if the
password contained only S's and H's.

I may have the S's and the H's a about f.

> Mind you, I can't figure how to solve it for using
>punched cards as an input medium.

Use a non-verifying punch to begin with.  Patch your OS so that it diverts
the appropriate cards into the alternate output hopper.  Keep a small fire
burning in that hopper.  Works for me.

>Tim Greening-Jackson
>E.S.O.C., 6100 Darmstadt, (What used to be West) Germany.

They moved it?

-- 
David Brooks				dbrooks at osf.org
Systems Engineering, OSF		uunet!osf.org!dbrooks



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