[Processors] Add named range to network condition for host's IPs

[a03nikki]

Describe the enhancement:

https://www.elastic.co/guide/en/beats/auditbeat/7.15/defining-processors.html#condition-network

network
The network condition checks if the field is in a certain IP network range. Both IPv4 and IPv6 addresses are supported. The network range may be specified using CIDR notation, like "192.0.2.0/24" or "2001:db8::/32", or by using one of these named ranges:
...

It would be great if we could have a named range for the IP addresses assigned to a host.

Describe a specific use case for the enhancement or feature:

It would be great if we could exclude (aka drop_event) not only the process communication on the loopback addresses (aka localhost) but communication between processes using the local host's IP address.

For example, host_ip would exclude the host's IP address is 172.16.3.17 (which would be 172.16.3.17/32 by CIDR notation I believe):

processors:
  - drop_event:
      when:
        network:
          destination.ip: [loopback, host_ip]

A work around could be #29266 or #29269, if we could compare source and destination IP addresses on events shipped by the Beats. Another work around would be to manually add the host's IPs using config management tool (e.g. Puppet, Ansible, etc.) to add the ranges such as 172.16.3.17/32 to the list.

[elasticmachine]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)

[legoguy1000]

loopback is already included

beats/libbeat/conditions/network.go

Line 46 in 055798a

"loopback": func(ip net.IP) bool { return ip.IsLoopback() },

. other host ips not yet.

[botelastic]

Hi!
We just realized that we haven't looked into this issue in a while. We're sorry!

We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1.
Thank you for your contribution!