Kubernetes offers a DNS cluster addon, which most of the supported environments enable by default. The source code is in cmd/kube-dns.
The Kubernetes DNS Admin Guide provides further details on this plugin.
The container containing the kube-dns binary needs to be built for every architecture and pushed to the registry manually whenever the kube-dns binary has code changes. Every significant change to the functionality should result in a bump of the TAG in the Makefile.
Any significant changes to the YAML template for kube-dns should result a bump
of the version number for the kube-dns replication controller and well as the
version label. This will permit a rolling update of kube-dns.