Re: Defenses against bad robots

Mordechai T. Abzug (mabzug1@gl.umbc.edu)
Fri, 17 May 1996 19:33:53 -0400 (EDT)


"K" == kathy@accessone.com spake thusly:

K> (D) Capture the robot in an infinite loop trap that does not
K> use too much resources. In the event that the infinite loop
K> trap is tripped, a message is printed to a file, etc. Please
K> reply with examples of simple infinite loops.

Easily done with a standard server. Set up a CGI script that's pointed to
by a URL that doesn't indicate it's a CGI. Now, note that many servers let
you add on more path info to a CGI URL and pass it to the CGI script in the
env. For instance, http://www.mydomain/script/111 and
http://www.mydomain/script/112 can activate the same script with a
different argument (which happens to be a number). Set up the CGI so it
reads the rest of the URL after it's own location as a sequence number, and
returns a text/html response that starts with the next number in the
sequence. No human should have patience to get to 100, particularly if the
link is the only thing there.

-- 
			  Mordechai T. Abzug
http://umbc.edu/~mabzug1   mabzug1@umbc.edu     finger -l mabzug1@gl.umbc.edu
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