Schlundtech Dynamic DNS updater

This packages provides a way to update DNS records programmatically, for customers of Schlundtech, using their XML-Gateway.

Many thanks to https://github.com/martinlowinski/php-dyndns for doing the heavy lifting of figuring out how to talk to the XML-Gateway in a way that actually makes it do what we want.

Usage

First, you need to create a subdomain with an A-record in your domain, say home.example.com, and install this package, e.g. with pip install ws.ddns (or git clone ...; pip install -e .)

Then you can use the command-line utility provided by this package, like so:

$ schlund-ddns --username USER --password PASS home.example.com 1.2.3.4

If you have both an A and AAAA record for the subdomain, you have to update them separately, i.e. call the script twice, once with an IPv4 and a second time with IPv6 address.

(See schlund-ddns --help for more configuration parameters, e.g. the context that you were told to use when applying for the XML-Gateway.)

Instead of passing the parameters on the commandline, you can instead call schlund-ddns --config myconfig.ini (see below for the file format).

Alternatively, set up the provided cgi script schlund-ddns-cgi to provide HTTP access. You'll need to provide username and password using a configuration file and then passing that file's path as an environment variable. Here's an example apache configuration snippet to do this:

ScriptAlias /dns-update /path/to/ddns/schlund-ddns-cgi
<Location /dns-update>
  SetEnv DDNS_CONFIG /path/to/ddns/config

  AuthName "Dynamic DNS"
  AuthType Basic
  AuthUserFile /path/to/ddns/htpasswd
  require valid-user
</Location>

The configuration file is a standard ini file and should look like this:

[default]
username = USER
password = PASS
context  = CONTEXT

You can optionally add an allowed_hostnames = one.example.com two.example.com whitespace-separated list to the config file, only those will then be accepted.

The HTTP protocol is modeled after the one from NoIP, that is, clients should perform a request like this to trigger a DNS update:

http://example.com/dns-update?hostname=home.example.com&myip=1.2.3.4

There is also a docker image of the HTTP service here: https://hub.docker.com/r/customelements/schlund-ddns

2FA support

• Install pip install pyotp in addition to this package
• Pass the 2FA secret (probably 16 characters, you may have to reverse-engineer them from the QR-Code used for setup) as --totp-secret` commandline or configuration parameter