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Old February 24th, 2004
zimon zimon is offline
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Join Date: May 29th, 2003
Posts: 14
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Quote:
Originally posted by MrJoe

It is perfectly valid to run a gnutella client on any port you want. However, with banning ports in the lower range it is likely to also ban valid alternate locations.

I think it is essential that clients implement both X-Alt and X-Nalt, (X-Nalt are the locations which are known to be bogus).
Gtk-gnutella emits both, but currently doesn't use the X-Nalt part itself yet.
So, If one wants to flood someone's HTTP server logs with "GET /uri-res/N2R/" requests, one is able just make bogus X-Alt (Alternate locations) replies with hits of most common requested files and there is nothing anyone can do about it except find the IP-addresses of those hosts and ban them from gnet?

Yet if the servents get X-Nalt information from some other servants telling victim.host.com:80 is bogus, they still have to decide which one to believe. If they blindly trust X-Nalt fields, then one can use that to cause DoS to valid gnet-servants also.

I think there is a risk someone starts to use gnet for DDOS with this feature.
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