WWW User authentication

Jeff Barber jeffb at sware.com
Tue Apr 9 15:52:19 PDT 1996


Brian C. Lane writes:

>   I just finished writing a cgi script to allow users to change their login
> passwords via a webpage. I currently have the webpage being authenticated
> with the basic option (uuencoded plaintext). MD5 would be nicer, but how
> many browsers actually support it?

AFAIK, none.  I don't see how this would be helpful anyway.  If you 
MD5 the password, I won't be able to snoop the password off the wire,
but I can simply snoop the MD5 hash off the wire instead and since 
that's what your authentication check must now be against, what does
this buy you?


>   When the user changes their password, the form sends their name, old
> password, and new password with it, in the clear. This is no worse than
> changing your password across a telnet connection, but I'd like it to be
> more secure, but useable by a large number of browsers.
> 
>   Any advice?

Well, if you use SSL, it's useable by a "large number of browsers" since
Netscape has such a large share of the browser market.  And then all of
the things you're doing w.r.t. authentication are hidden, at least from
casual eavesdroppers and others too if you use more than the 40-bit option.
There's really no other choice to reach a large number of browsers.


-- Jeff






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