Oh yeah, that is such standard practice for me that I forgot to mention it.
checksum = secret on server + cookie value

What is a "nonce"? I'm guessing an id that is marked as used so prevent 
multiple submissions?

Drew

At 05:02 PM 4/23/02 -0500, David Turner wrote:
>.... but they bad guys will just change your checksum, too.  Instead,
>concatenate with some secret stored on your disk, and a nonce (to
>prevent reply attacks), *then* checksum.
>
>On Tue, 2002-04-23 at 15:11, Drew Taylor wrote:
> > There's two ways to do this: the expire time on the cookie (less reliable)
> > or setting an expire time as part of the cookie value (more reliable). And
> > if you're using a cookie for anything other than a cryptographically 
> random
> > session id, be sure to add a checksum (MD5 or SHA1) so you can detect
> > tampering.
> >
> > Drew
> >
> > At 03:53 PM 4/23/02 -0400, John Saylor wrote:
> >
> > >( 02.04.23 15:16 -0400 ) Sean Quinlan:
> > > > How do I either scrub the header or force Apache to resend the login
> > > > request?
> > >
> > >If you use cookies to keep state, you can set a time stamp on them that
> > >will force reauthentication once they expire.
> >
> > ======================================================================
> > Drew Taylor                     JA[P|m_p]H
> > http://www.drewtaylor.com/      Just Another Perl|mod_perl Hacker
> > mailto:[EMAIL PROTECTED]      *** God bless America! ***
> > ----------------------------------------------------------------------
> > Speakeasy.net: A DSL provider with a clue. Sign up today.
> > http://www.speakeasy.net/refer/29655
> > ======================================================================
>--
>-Dave Turner                              Stalk Me: 617 441 0668
>"Anyone who has seen, for example, the film Final Fantasy: The
>Spirits Within (H. Sakaguchi and M. Sakakibara directors, 2001)
>can understand the Government's concern." -Justice Sandra Day
>O'Connor, http://supct.law.cornell.edu/supct/html/00-795.ZX.html

======================================================================
Drew Taylor                     JA[P|m_p]H
http://www.drewtaylor.com/      Just Another Perl|mod_perl Hacker
mailto:[EMAIL PROTECTED]      *** God bless America! ***
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Speakeasy.net: A DSL provider with a clue. Sign up today.
http://www.speakeasy.net/refer/29655
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