dnsit

README

dnsit

simple as that dns server, accepts /etc/hosts like config for resolving A records

installation

go install github.com/Semior001/dnsit@latest

docker run --rm -it -p 53:53/udp -v ./my-config-file.conf:/srv/config ghcr.io/semior001/dnsit:latest

usage

Usage:
  dsnit [OPTIONS]

Application Options:
      --addr=                  Address to listen on (default: :53) [$ADDR]
      --upstream=              Upstream DNS server address [$UPSTREAM]
      --ttl=                   TTL for DNS records (default: 5m) [$TTL]

config:
      --config.path=           Path to the configuration file [$CONFIG_PATH]
      --config.delay=          Delay before applying changes (default: 10s) [$CONFIG_DELAY]
      --config.check-interval= Interval to check for config changes (default: 3s) [$CONFIG_CHECK_INTERVAL]

tailscale:
      --tailscale.tailnet=     Tailscale tailnet [$TAILSCALE_TAILNET]
      --tailscale.token=       Tailscale API token [$TAILSCALE_TOKEN]

log:
      --log.path=              Log file path, empty for stdout [$LOG_PATH]
      --log.debug              Enable debug mode [$LOG_DEBUG]

Help Options:
  -h, --help                   Show this help message

configuration

Config is just like a /etc/hosts file, but with some additional options in comments.

In comment, you can provide a #!!from: cidr directive, which will make the next set of records (until the next !!from directive) record only available for the specified CIDR.

Example:

#!!from: 192.168.174.0/24
192.168.174.2   example.com   deeper.example.com
192.168.174.3   foo.bar.com

#!!from: 100.10.10.1/32
100.10.10.2     example.com
100.10.10.5     blah.abacaba.com

#!!tstag:
#!!  - 'tag:foo'
#!!  - 'tag:bar'
127.0.0.1      example.com

This will make example.com and deeper.example.com resolve to 192.168.174.2 only for clients from 192.168.174.0/24 subnet, and example.com and blah.abacaba.com resolve to 100.10.10.2 and 100.10.10.5 respectively only for clients from 100.10.10.1/32 subnet.

The third section with #!!tstag directive will make example.com resolve to the localhost IP address only for clients with foo or bar tag, tags are received from the Tailscale API.

You can invoke a special query nslookup semior001.dnsit.refresh-tailscale to force the server to refresh the tags from the Tailscale API.

project status

This project is in a very early stage of development, so it may not work as expected. Until v1 is released, the API may change at any time.

Documentation

Overview

Package main is an application entrypoint.