DNScrypt is a protocol for securing communications between a client and a DNS resolver, using high-speed high-security elliptic-curve cryptography.

While not providing end-to-end security, it protects the local network, which is often the weakest point of the chain, against man-in-the-middle attacks.

dnscrypt-proxy is a client-implementation of the protocol. It requires a DNSCrypt server on the other end.

• dnscrypt-proxy documentation
• dnscrypt website.

dnscrypt-proxy can be downloaded here: dnscrypt-proxy download.

Signatures can be verified with Minisign:

$ minisign -VP RWQf6LRCGA9i53mlYecO4IzT51TGPpvWucNSCh1CBM0QTaLn73Y7GFO3 -m dnscrypt-proxy-1.9.1.tar.bz2

Aside from implementing the protocol, dnscrypt-proxy can be extended with plug-ins, and gives a lot of control on the local DNS traffic:

• Review the DNS traffic originating from your network in real time, and detect compromised hosts and applications phoning home.
• Locally block ads, trackers, malware, spam, and any website whose domain names or IP addresses match a set of rules you define.
• Prevent queries for local zones from being leaked.
• Reduce latency by caching resposes and avoiding requesting IPv6 addresses on IPv4-only networks.
• Force traffic to use TCP, to route it through TCP-only tunnels or Tor.