[feature request] Support network in reverse_pointer filter

[felixauringer]

SUMMARY

I would like to be able to pipe an IP network in CIDR notation into the reverse_pointer filter.

'192.168.10.0/24' | community.dns.reverse_pointer => 10.168.192.in-addr.arpa

ISSUE TYPE

• Feature Idea

COMPONENT NAME

Regards the existing filter reverse_pointer which currently errors in my use case.

ADDITIONAL INFORMATION

I am configuring dnsmasq and would like to delegate reverse lookups for a specific subnet to another dnsmasq server. The correct configuration for that would be:

server=/10.168.192.in-addr.arpa/dns2.example.internal

In my playbook, I usually use network ranges in CIDR notation to process them with ansible's ipaddr module. The best solution currently is to extract the IP address from the CIDR notation with the ipaddr module, then get the domain for that with the reverse_pointer filter and then do some string slicing.

[felixfontein]

ipaddress.ip_network(value) parses CIDR notation. The resulting object also has a reverse_pointer property, but that returns nonsense for networks (ipaddress.ip_network("192.168.10.0/24").reverse_pointer gives 0/24.10.168.192.in-addr.arpa). ipaddress.ip_network("192.168.10.0/24")[0].reverse_pointer gives 0.10.168.192.in-addr.arpa, and ipaddress.ip_network("192.168.10.0/24").prefixlen gives 24. From that it should be doable.

I guess the main question is what to do if the prefix length is not a multiple of 8. For example, what should '192.168.10.0/28' | community.dns.reverse_pointer be?

[felixfontein]

@felixauringer ping.