1 files changed, 18 insertions, 0 deletions
diff --git a/lib/puppet/functions/dns/rev_record.rb b/lib/puppet/functions/dns/rev_record.rb
new file mode 100644
index 0000000..efbedc6
--- /dev/null
+++ b/lib/puppet/functions/dns/rev_record.rb
@@ -0,0 +1,18 @@
+require 'ipaddr'
+
+Puppet::Functions.create_function(:'dns::rev_record') do
+  dispatch :rev_record do
+    param 'Stdlib::IP::Address::V6::Nosubnet', :ip
+    param 'Stdlib::IP::Address::V6::Nosubnet', :netmask
+    return_type 'Tuple[String,2]'
+  end
+
+  def rev_record(ip, netmask)
+    cidr = IPAddr.new("::/#{netmask}").prefix
+    addr = IPAddr.new ip
+    parts = addr.ip6_arpa.split('.')
+
+    [ parts.take(cidr/4).join('.'), 
+      parts.drop(cidr/4).join('.') ]
+  end
+end