# TOR SUPPORT IN DASH CORE It is possible to run Dash Core as a Tor hidden service, and connect to such services. The following directions assume you have a Tor proxy running on port 9050. Many distributions default to having a SOCKS proxy listening on port 9050, but others may not. In particular, the Tor Browser Bundle defaults to listening on port 9150. See [Tor Project FAQ:TBBSocksPort](https://www.torproject.org/docs/faq.html.en#TBBSocksPort) for how to properly configure Tor. ## 1. Run Dash Core behind a Tor proxy The first step is running Dash Core behind a Tor proxy. This will already anonymize all outgoing connections, but more is possible. -proxy=ip:port Set the proxy server. If SOCKS5 is selected (default), this proxy server will be used to try to reach .onion addresses as well. -onion=ip:port Set the proxy server to use for Tor hidden services. You do not need to set this if it's the same as -proxy. You can use -noonion to explicitly disable access to hidden service. -listen When using -proxy, listening is disabled by default. If you want to run a hidden service (see next section), you'll need to enable it explicitly. -connect=X When behind a Tor proxy, you can specify .onion addresses instead -addnode=X of IP addresses or hostnames in these parameters. It requires -seednode=X SOCKS5. In Tor mode, such addresses can also be exchanged with other P2P nodes. -onlynet=tor Only connect to .onion nodes and drop IPv4/6 connections. An example how to start the client if the Tor proxy is running on local host on port 9050 and only allows .onion nodes to connect: ./dashd -onion=127.0.0.1:9050 -onlynet=tor -listen=0 -addnode=ssapp53tmftyjmjb.onion In a typical situation, this suffices to run behind a Tor proxy: ./dashd -proxy=127.0.0.1:9050 ## 2. Run a Dash Core hidden server If you configure your Tor system accordingly, it is possible to make your node also reachable from the Tor network. Add these lines to your /etc/tor/torrc (or equivalent config file): *Needed for Tor version 0.2.7.0 and older versions of Tor only. For newer versions of Tor see [Section 4](#4-automatically-listen-on-tor).* HiddenServiceDir /var/lib/tor/dashcore-service/ HiddenServicePort 9999 127.0.0.1:9999 HiddenServicePort 19999 127.0.0.1:19999 The directory can be different of course, but (both) port numbers should be equal to your dashd's P2P listen port (9999 by default). -externalip=X You can tell Dash Core about its publicly reachable address using this option, and this can be a .onion address. Given the above configuration, you can find your .onion address in /var/lib/tor/dashcore-service/hostname. For connections coming from unroutable addresses (such as 127.0.0.1, where the Tor proxy typically runs), .onion addresses are given preference for your node to advertise itself with. -listen You'll need to enable listening for incoming connections, as this is off by default behind a proxy. -discover When -externalip is specified, no attempt is made to discover local IPv4 or IPv6 addresses. If you want to run a dual stack, reachable from both Tor and IPv4 (or IPv6), you'll need to either pass your other addresses using -externalip, or explicitly enable -discover. Note that both addresses of a dual-stack system may be easily linkable using traffic analysis. In a typical situation, where you're only reachable via Tor, this should suffice: ./dashd -proxy=127.0.0.1:9050 -externalip=ssapp53tmftyjmjb.onion -listen (obviously, replace the .onion address with your own). It should be noted that you still listen on all devices and another node could establish a clearnet connection, when knowing your address. To mitigate this, additionally bind the address of your Tor proxy: ./dashd ... -bind=127.0.0.1 If you don't care too much about hiding your node, and want to be reachable on IPv4 as well, use `discover` instead: ./dashd ... -discover and open port 9999 on your firewall (or use -upnp). If you only want to use Tor to reach .onion addresses, but not use it as a proxy for normal IPv4/IPv6 communication, use: ./dashd -onion=127.0.0.1:9050 -externalip=ssapp53tmftyjmjb.onion -discover ## 3. List of known Dash Core Tor relays Note: All these nodes are hosted by masternodehosting.com * l7oq3v7ujau5tfrw.onion * vsmegqxisccimsir.onion * 4rbha5nrjso54l75.onion * 3473226fvgoenztx.onion * onn5v3aby2dioicx.onion * w5n7s2p3mdq5yf2d.onion * ec4qdvujskzasvrb.onion * g5e4hvsecwri3inf.onion * ys5upbdeotplam3y.onion * fijy6aikzxfea54i.onion ## 4. Automatically listen on Tor Starting with Tor version 0.2.7.1 it is possible, through Tor's control socket API, to create and destroy 'ephemeral' hidden services programmatically. Dash Core has been updated to make use of this. This means that if Tor is running (and proper authentication has been configured), Dash Core automatically creates a hidden service to listen on. This will positively affect the number of available .onion nodes. This new feature is enabled by default if Dash Core is listening (`-listen`), and requires a Tor connection to work. It can be explicitly disabled with `-listenonion=0` and, if not disabled, configured using the `-torcontrol` and `-torpassword` settings. To show verbose debugging information, pass `-debug=tor`. Connecting to Tor's control socket API requires one of two authentication methods to be configured. For cookie authentication the user running dashd must have write access to the `CookieAuthFile` specified in Tor configuration. In some cases, this is preconfigured and the creation of a hidden service is automatic. If permission problems are seen with `-debug=tor` they can be resolved by adding both the user running Tor and the user running dashd to the same group and setting permissions appropriately. On Debian-based systems the user running dashd can be added to the debian-tor group, which has the appropriate permissions. An alternative authentication method is the use of the `-torpassword` flag and a `hash-password` which can be enabled and specified in Tor configuration. ## 5. Privacy recommendations - Do not add anything but Dash Core ports to the hidden service created in section 2. If you run a web service too, create a new hidden service for that. Otherwise it is trivial to link them, which may reduce privacy. Hidden services created automatically (as in section 3) always have only one port open.