Autogenerate reverse zones

Author: nadvornik

bind/config.sls

@@ -1,4 +1,5 @@
 {% from "bind/map.jinja" import map with context %}
+{% from "bind/reverse_zone.jinja" import generate_reverse %}
 
 include:
   - bind
@@ -175,6 +176,9 @@ bind_rndc_client_config:
 {% for zone, zone_data in view_data.get('configured_zones', {}).items() -%}
 {%- set file = salt['pillar.get']("bind:available_zones:" + zone + ":file", false) %}
 {%- set zone_records = salt['pillar.get']('bind:available_zones:' + zone + ':records', {}) %}
+{%- if salt['pillar.get']('bind:available_zones:' + zone + ':generate_reverse') %}
+{%-   do generate_reverse(zone_records, salt['pillar.get']('bind:available_zones:' + zone + ':generate_reverse:net'), salt['pillar.get']('bind:available_zones:' + zone + ':generate_reverse:for_zones'), salt['pillar.get']('bind:available_zones', {})) %}
+{%- endif %}
 {# If we define RRs in pillar, we use the internal template to generate the zone file
    otherwise, we fallback to the old behaviour and use the declared file
 #}

bind/reverse_zone.jinja

@@ -0,0 +1,23 @@
+{%- macro generate_reverse(zone_records, net, for_zones, available_zones) %}
+{%-     set res = {} %}
+{%-     set net = salt['network.calc_net'](net) %}
+{%      set for_zones = [ for_zones ] if for_zones is string else for_zones %}
+{%-     for zone in for_zones %}
+{%-         set A_records = available_zones.get(zone, {}).get('records', {}).get('A', {}) %}
+{%-         for name, addr_list in A_records|dictsort %}
+{%-             set addr_list = [ addr_list ] if addr_list is string or addr_list is number else addr_list %}
+{%-             for addr in addr_list %}
+{%-                 if salt['network.ip_in_subnet'](addr, net) %}
+{%-                     if name.endswith('.') %}
+{%-                         set full_name = name %}
+{%-                     else  %}
+{%-                         set full_name = name + '.' + zone + '.'  %}
+{%-                     endif %}
+{%-                     set rev_ip = '.'.join(addr.split('.')[::-1]) %}
+{%-                     do res.update({rev_ip + '.in-addr.arpa.': full_name}) %}
+{%-                 endif %}
+{%-             endfor %}
+{%-         endfor %}
+{%-     endfor %}
+{%-     do zone_records.update({'PTR': res }) %}
+{%- endmacro %}

pillar.example

@@ -302,6 +302,31 @@ bind:
             - '"v=spf1 mx a ip4:1.2.3.4 ~all"'
           _dmarc: '"v=DMARC1; p=quarantine; rua=mailto:[email protected]; fo=1:d:s; adkim=r; aspf=r; pct=100; ri=86400"'
 
+
+
+
+    3.2.1.in-addr.arpa:                           # auto-generated reverse zone
+      file: example.com.rev.txt
+      soa:                                        # Declare the SOA RRs for the zone
+        ns: ns1.example.com                       # Required
+        contact: hostmaster.example.com           # Required
+        serial: auto                              # autoupdate serial on each change
+        class: IN                                 # Optional. Default: IN
+        refresh: 8600                             # Optional. Default: 12h
+        retry: 900                                # Optional. Default: 15m
+        expiry: 86000                             # Optional. Default: 2w
+        nxdomain: 500                             # Optional. Default: 1m
+        ttl: 8600                                 # Optional. Not set by default
+      records:                                    # Records for the zone, grouped by type
+        NS:
+          '@':
+            ns1.example.com.
+      generate_reverse:                           # take all A records from example.com that are in 1.2.3.0/24 subnet
+        net: 1.2.3.0/24                           # and generate reverse records for them
+        for_zones:
+          - example.com                           # example.com is a zone defined in pillar, see above
+
+
 ### Externally defined Zones ###
 bind:
   available_zones: