[Gllug] validator bug

[SteveC]

bit OT, but maybe you guys can help. I emailed this to the w3c html 
validation list but got ignored. Does anyone agree with below?

validator.w3.org is a bunch of scripts that validates html and points 
out where you screwed up.

It appears possible to ask the validator to check itself, then check
itself checking itself, then check itself checking itself checking
itself and so on recursively.

I tried the first 6 levels of recursion and got a roughly linearly
increasing delay of about and extra second per recursion level. This
makes it interesting as a DoS attack as you could cause multiple amounts
of load on the machine for trivial increase in network traffic.

I don't know if it is actually calling itself, but the increasing load 
time would seem to suggest it (see below).



time wget http://validator.w3.org/

real    0m0.651s
user    0m0.020s
sys     0m0.000s

time wget 
http://validator.w3.org/check?uri=http%3A%2F%2Fvalidator.w3.org%2F

real    0m1.751s
user    0m0.010s
sys     0m0.010s

 time wget
http://validator.w3.org/check?uri=http%3A%2F%2Fvalidator.w3.org%2Fcheck%3Furi%3Dhttp%253A%252F%252Fvalidator.w3.org%252F

real    0m2.428s
user    0m0.000s
sys     0m0.020s

time wget 
http://validator.w3.org/check?uri=http%3A%2F%2Fvalidator.w3.org%2Fcheck%3Furi%3Dhttp%253A%252F%252Fvalidator.w3.org%252Fcheck%253Furi%253Dhttp%25253A%25252F%25252Fvalidator.w3.org%25252Fcheck%25253Furi%25253Dhttp%2525253A%2525252F%2525252Fvalidator.w3.org%2525252F

real    0m3.433s
user    0m0.020s
sys     0m0.010s

time wget
http://validator.w3.org/check?uri=http%3A%2F%2Fvalidator.w3.org%2Fcheck%3Furi%3Dhttp%253A%252F%252Fvalidator.w3.org%252Fcheck%253Furi%253Dhttp%25253A%25252F%25252Fvalidator.w3.org%25252Fcheck%25253Furi%25253Dhttp%2525253A%2525252F%2525252Fvalidator.w3.org%2525252Fcheck%2525253Furi%2525253Dhttp%252525253A%252525252F%252525252Fvalidator.w3.org%252525252F

real    0m7.199s
user    0m0.010s
sys     0m0.020s

time wget
http://validator.w3.org/check?uri=http%3A%2F%2Fvalidator.w3.org%2Fcheck%3Furi%3Dhttp%253A%252F%252Fvalidator.w3.org%252Fcheck%253Furi%253Dhttp%25253A%25252F%25252Fvalidator.w3.org%25252Fcheck%25253Furi%25253Dhttp%2525253A%2525252F%2525252Fvalidator.w3.org%2525252Fcheck%2525253Furi%2525253Dhttp%252525253A%252525252F%252525252Fvalidator.w3.org%252525252Fcheck%252525253Furi%252525253Dhttp%25252525253A%25252525252F%25252525252Fvalidator.w3.org%25252525252F

real    0m6.063s
user    0m0.010s
sys     0m0.010s


have fun,

SteveC steve at fractalus.com http://www.fractalus.com/steve/

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