MAPADDRESS for IP ranges (CIDR, etc)
The general idea is to have MAPADDRES match blocks of IP addresses with one rule: MAPADDRESS 188.8.131.52/18 184.108.40.206/18..exit
Very useful for: o Same as domain wildcarding... o Constraining known destination ranges to an exit. VPN's, corporate/edu DMZ's, location aware services, location/IP restricted services, etc. o Catchall for unexpected/unknown use of IP's. Such as websites that code them in html page elements, services such as multimedia farms, places that don't use FQDNS, etc. If you know one IP (manual resolve, or see one pop up), you can MAP out a good sized CIDR block without disturbing your other Tor traffic. o Simplicity, fewer MAP rules.
Further rationale, examples and extensions... DOMAINS: http://archives.seul.org/or/dev/Jun-2009/msg00011.html http://archives.seul.org/or/dev/Jun-2009/msg00023.html CIDR: http://archives.seul.org/or/talk/Oct-2009/msg00150.html http://archives.seul.org/or/talk/Mar-2011/msg00154.html MISC: http://archives.seul.org/or/talk/Aug-2009/msg00295.html http://archives.seul.org/or/talk/Dec-2010/msg00175.html http://archives.seul.org/or/talk/Mar-2011/msg00144.html
Split from ticket - MAPADDRESS for Domains: https://trac.torproject.org/projects/tor/ticket/933
"[We] need to figure out (or somebody else would figure out) how this would interact with DNS resolution. :)" --NickM
It's already figured out... DNS is just a user/app layer on top of Tor's network transport, and thus DNS is not involved :)
Tor just needs to grab whatever IP's the client ultimately requests to get to via SOCKS/TransPort (if and after any DNS [resolved via SOCKS, the host, or otherwise]), and route them through the MAPPED exit... if the user specified such a MAP for said IP's.