dnschain

A blockchain-based DNS + HTTP server that fixes HTTPS security, and more!

DNSChain

DNSChain (formerly DNSNMC) makes it possible to be certain that you're communicating with who you want to communicate with, and connecting to the sites that you want to connect to, without anyone secretly listening in on your conversations in between.

What is it?

DNSChain replaces X.509 PKI with the blockchain

X.509 PKI makes and breaks today's Internet security. It's what makes your browser think "The connection to this website is secure" when it's not. It's what we have to get rid of, and DNSChain provides a scalable, distributed, and decentralized replacement that doesn't depend on untrustworthy "authority figures": ︎

DNSChainX.509 PKI with or without Certificate Transparency
MITM-proof authentication [1]:white_check_mark::x:
Secure and simple GPG key distribution:white_check_mark::x:
Free and actually-secure SSL certificates [2]:white_check_mark::x:
Stops many denial-of-service attacks [3]:white_check_mark::x:
Certificate revocation that actually works [4]:white_check_mark::x:
DNS-based censorship circumvention [5]:white_check_mark::x:
Prevents domain theft ("seizures"):white_check_mark::x:
Access blockchain-based domains like .bit:white_check_mark::x:
RESTful API to blockchain via .dns metaTLD:white_check_mark::x:
Simple design fits in about 600 lines of CoffeeScript!:white_check_mark::x:

Simple and secure GPG key distribution

Well, simple to share, a little more difficult to register it (at the moment only, give it time ^_^):

  1. Use namecoind to register your identity in the id/ namespace.
  2. Use a DNSChain server that exposes its .dns meta-TLD through the traditional DNS, as shown in the screenshot.

It's always best to use your own server, of course. Note: headers containing a crypographic signature will be sent soon!

Free SSL certificates become possible

SSL certificates today do not provide the security that they claim to provide. DNSChain replaces Certificate Authorities by providing a means for distributing public keys in a way that is secure from MITM attacks.

Prevents DDoS attacks

Unlike traditional DNS servers, DNSChain encourages widespread deployment of the server (ideally, "one for every group of friends"). This distributed, flat topology eliminates the need for open resolvers by making it practical to limit clients to a small, trusted set. Additionally, whereas traditional DNS resolvers must query other DNS servers to answer queries, blockchain-based DNS resolvers have no such requirement because all of the data necessary to answer queries is stored locally on the server.

Another DoS attack relates to the centralized manner in which today's SSL certificates are checked for revocation:

Certificate revocation that actually works

TODO: OCSP + DoS.

DNS-based censorship circumvention

The developers of Unblock.us.org and DNSChain are teaming up to bring the anti-censorship features of Unblock.us into DNSChain. Each project benefits from the other: DNSChain ensures MITM-free communication and Unblock.us ensures that the communication passes through firewalls.

The Unblock.us feature is optional and is up to the server administrator to enable and configure to their needs. It uses MITM to defeat censorship at its own game.

Unblock.us works by hijacking the DNS lookups for the domains on a list defined by the server administrator. The server then accepts all HTTP and HTTPS traffic addressed to those domains and forwards it intelligently. Even though it can't decrypt SSL traffic, it can still forward it. It's as fast as a VPN (unlike Tor) and ONLY tunnels the traffic to those domains, meaning that it doesn't affect other online activites (unlike VPNs and Tor) and isn't costly in server bandwidth. Finally, there's no software to install, only DNS settings to change. It has been confirmed to work in Turkey, UK, Kuwait, UAE and many additional Middle Eastern countries.

For now, Deep Packet Inspection techniques used in Pakistan and China can still beat Unblock.us, but the next version will address that issue using a technique called Host Tunneling. Short of cutting entire countries off the internet, DNSChain/Unblock.us will be able to get through.

The .dns meta-TLD

.dns is a meta-TLD because unlike traditional TLDs, it is not meant to globally resolve to a specific IP. Rather, it is meant to resolve to a DNSChain server that you personally own and run.

It bears emphasizing that you cannot register a meta-TLD because you already own them!

When a DNSChain server sees a request to a .dns domain, it handles the request itself, looking it up in a blockchain stored on that same server. At the moment, DNSChain uses the Namecoin blockchain, but it can easily be configured to use any blockchain.

How do I use it?

No special software is required, just set your computer's DNS settings to use one of the public DNSChain servers (more secure to run your own though).

Then try the following:

Don't want to change your DNS settings?

As a convenience, the first DNSChain server's .dns meta-TLD can be accessed over the old-DNS by way of dns.dnschain.net, like so:

This means you can immediately begin writing JavaScript apps that query the blockchain. :)

Free public DNSChain servers

DNSChain is meant to be run by individuals!

Yes, you can use a public DNSChain server, but it's far better to use your own because it gives you more privacy, makes you more resistant to censorship, and provides you with a stronger guarantee that the responses you get haven't been tampered with by a malicious server.

Those who do not own their own server or VPS can use their friend's (as long as they trust that person). DNSChain servers will sign all of their responses, thus protecting your from MITM attacks. (NOTE: signing is not yet implemented, but will be soon)

You can, if you must, use a public DNSChain server. Simply set your computer's DNS settings to one of these. Note that some of the servers must be used with dnscrypt-proxy.

IP or DNSCrypt providerDNSCrypt InfoLogsLocationOwnerNotes
192.184.93.146 (aka d/okturtles)N/ANoAtlanta, GAid/greg
54.85.5.167 (aka name.thwg.org)N/ANoUSAid/wozz
2.dnscrypt-cert.okturtles.comRequired InfoNoAtlanta, GAid/greg
2.dnscrypt-cert.soltysiak.comRequired InfoNoPoznan, Poland@maciejsoltysiakIPv6 available

Tell us about yours by opening an issue (or any other means) and we'll list it here!

We'll post the public keys for these servers here as well once signed DNS & HTTP responses are implemented. Note that DNSChain + DNSCrypt servers already guarantee the authenticity of DNS responses.

Registering .bit domains and identities

.bit domains and public identities are currently stored in the Namecoin P2P network. It's very similar to the Bitcoin network.

All of this must currently be done using namecoind, a daemon that DNSChain requires running in the background to access the Namecoin network.

See the Namecoin wiki for more info:

How do I run my own?

Get yourself a Linux server (they come as cheap as $2/month), and then make sure you have the following software installed:

Requirements

  1. nodejs and npm - We recommend using a package manager to install them.
  2. coffee-script (version 1.7.1+) - install via npm install -g coffee-script
  3. grunt-cli - install via npm install -g grunt-cli, provides the grunt command.
  4. namecoind - instructions