TorDNSEL: A Tor DNS-based Exit List

For an overview, see the man page at doc/tordnsel.8.

The design document for TorDNSEL can be found at:

    https://gitweb.torproject.org/tordnsel.git/tree/doc/torel-design.txt

Currently, only query type 1 from torel-design.txt is supported:

A request for the A record "1.0.0.10.80.4.3.2.1.ip-port.exitlist.example.com"
would return 127.0.0.2 if there's a running Tor node at 10.0.0.1 that allows
exits to port 80 at 1.2.3.4 and our ZoneOfAuthority is set to
"exitlist.example.com". If there isn't such an exit node, we return NXDOMAIN.
If the query is unsolicited and outside our zone of authority, we return
REFUSED.

Presumably, users of software with built-in support for DNSBLs would configure
[service port].[service address].ip-port.exitlist.example.com as a DNSBL.

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Dependencies

  TorDNSEL requires GHC 7.6. If you're running Debian Jessie:

    apt-get install ghc libghc-hunit-dev libghc-binary-dev libghc-conduit-dev \
      libghc-conduit-extra-dev libghc-mtl-dev libghc-network-dev  libghc-stm-dev

  OpenSSL's libcrypto is required for strong random numbers:

    apt-get install libssl-dev

  On non-Debian systems use your system's package manager or grab a binary
  distribution from the GHC website:

    http://haskell.org/ghc/download.html


Building TorDNSEL

    ./Setup.lhs configure
    ./Setup.lhs build

  If you want a tordnsel binary installed in /usr/local/bin:

    sudo ./Setup.lhs copy

Configuring TorDNSEL

  Copy config/tordnsel.conf.sample. At the very least, you'll need to uncomment
  and modify ZoneOfAuthority, DomainName, SOARName, StateDirectory,
  RuntimeDirectory, and probably DNSListenAddress.

  To run exit tests, you'll need to specify at least EnableActiveTesting,
  TestListenAddress, and TestDestinationAddress.

  Load a config file with the -f option.

  Options listed in tordnsel.conf.sample can also be specified on the command
  line:

    ./tordnsel -f /etc/tordnsel.conf --ZoneOfAuthority exitlist.example.com

  Command line options override those included in a config file.

  TorDNSEL needs an accurate system clock, so it would be a good idea to run
  an ntpd.

Running TorDNSEL practically

  cp config/tordnsel-init.d-script.sample /etc/init.d/tordnsel
  chmod +x /etc/init.d/tordnsel
  cp config/tordnsel.conf.sample /etc/tordnsel.conf
  # Configure it
  vim /etc/tordnsel.conf
  addgroup --system tordnsel
  adduser --ingroup tordnsel --system --no-create-home \
    --home /var/lib/tordnsel tordnsel
  mkdir /var/lib/tordnsel

  update-rc.d tordnsel defaults
  /etc/init.d/tordnsel start