add update-hetzner-rdns hook

default.conf

@@ -39,4 +39,5 @@ lxc.hook.clone = /etc/lxc/hooks/remove-journal
 lxc.hook.clone = /etc/lxc/hooks/cleanup-lxc-config
 lxc.hook.clone = /etc/lxc/hooks/create-lxc-config
 lxc.hook.clone = /etc/lxc/hooks/update-zone
+lxc.hook.clone = /etc/lxc/hooks/update-hetzner-rdns
 lxc.hook.clone = /etc/lxc/hooks/ansible

hooks/update-hetzner-rdns

@@ -0,0 +1,90 @@
+#!/usr/bin/env ruby
+require 'net/http'
+require 'netaddr'
+require 'json'
+require 'pathname'
+
+LXC_ROOT = Pathname.new("/etc/lxc")
+CONTAINER_DATA = LXC_ROOT.join("container.json")
+
+class Hetzner
+  BASE_URI = URI("https://robot-ws.your-server.de")
+  def initialize(user, password)
+    @user = user
+    @password = password
+  end
+
+  def get(path)
+    resp = perform_request(Net::HTTP::Get.new(uri_for(path)))
+    JSON.parse(resp.body)
+  end
+
+  def post(path, params={})
+    req = Net::HTTP::Post.new(uri_for(path))
+    req.set_form_data(params)
+    resp = perform_request(req)
+    JSON.parse(resp.body)
+  end
+
+  def put(path, params={})
+    req = Net::HTTP::Put.new(uri_for(path))
+    req.set_form_data(params)
+    resp = perform_request(req)
+    JSON.parse(resp.body)
+  end
+
+  def delete(path)
+    perform_request(Net::HTTP::Delete.new(uri_for(path)))
+  end
+
+private
+  def uri_for(path)
+    u = BASE_URI.clone
+    u.path = path
+    u
+  end
+
+  def perform_request(req)
+    req.basic_auth(@user, @password)
+    resp = Net::HTTP.start(BASE_URI.hostname,
+                           BASE_URI.port,
+                           use_ssl: true) do |http|
+      http.request(req)
+    end
+    if resp.code.start_with? "2"
+      return resp
+    else
+      raise StandardError.new("failed to perform request: #{resp.inspect}")
+    end
+  end
+end
+def update_hetzner_rdns6(user, password, json)
+  api = Hetzner.new(user, password)
+  rdns = api.get("/rdns")
+  records = {}
+  rdns.each do |val|
+    rec = val["rdns"]
+    cidr = NetAddr::CIDR.create(rec["ip"])
+    next if cidr.version == 4
+    records[cidr.ip] = rec["ptr"]
+  end
+  json["network"].each do |host, data|
+    cidr = data["ipv6"]
+    next if cidr.nil?
+    ipv6 = NetAddr::CIDR.create(cidr).ip
+    hostname = data["rdns6"] || "#{host}.higgsboson.tk"
+    ptr = records.delete(ipv6)
+    if ptr.nil? or ptr != hostname
+      api.post("/rdns/#{ipv6}", ptr: hostname)
+    end
+  end
+  records.each do |ip, ptr|
+    api.delete("/rnds/#{ip}")
+  end
+end
+
+credentials = File.read("/etc/lxc/hetzner.key")
+json = JSON.load(File.open(CONTAINER_DATA))
+user, password = credentials.split(":")
+update_hetzner_rdns6(user, password, json)
+puts("ok")