Simple list format for gravity.list and black.list

[DL6ER]

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10

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This PR introduces a few improvements for huge block lists:

• File size of lists is reduced by a factor of 3-4x:
  • no need for HOSTS format with tons of repeated information where the IP addresses are often longer than the blocked entries
  • no need for adding two entries for IPv4 and IPv6
• Speed up of list importing of about factor 2x
  • we have to prepare the IP structures for lists only once
• Flexibility
  • as we fully control the addition of host entries in the FTL codebase, we can change details and add e.g. NXDOMAIN information so that exact blocking with NXDOMAIN replies becomes possible.

This PR has the advantage of removing unnecessary overhead introduced by config or HOSTS notation as this does not add any additional information here.

If we agree on this, I will add exact NXDOMAIN blocking in a follow-up PR.

Note that this PR depends on you having checked out FTLDNS-gravity-simplelists and ran gravity at least once on this branch. Further details here: pi-hole/pi-hole#2140

This template was created based on the work of udemy-dl.

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/implement-response-zone-policies-nxdomain-for-end-user-performance-increase/1342/19

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/implement-response-zone-policies-nxdomain-for-end-user-performance-increase/1342/27

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/nxdomain-and-null-blocking-with-ftldns/9634/1