firewall: T970: Add firewall group domain-group

Domain group allows to filter addresses by domain main
Resolved addresses as elements are stored to named "nft set"
that used in the nftables rules
Also added a dynamic "resolver" systemd daemon
vyos-domain-group-resolve.service which starts python script
for the domain-group addresses resolving by timeout 300 sec

set firewall group domain-group DOMAINS address 'example.com'
set firewall group domain-group DOMAINS address 'example.org'
set firewall name FOO rule 10 action 'drop'
set firewall name FOO rule 10 source group domain-group 'DOMAINS'
set interfaces ethernet eth0 firewall local name 'FOO'

nft list table ip filter
table ip filter {
  set DOMAINS {
    type ipv4_addr
    flags interval
    elements = { 192.0.2.1, 192.0.2.85,
	         203.0.113.55, 203.0.113.58 }
  }
  chain NAME_FOO {
    ip saddr @DOMAINS counter packets 0 bytes 0 drop comment "FOO-10"
    counter packets 0 bytes 0 return comment "FOO default-action accept"
  }
}

1 files changed, 8 insertions, 0 deletions

diff --git a/data/templates/firewall/nftables.j2 b/data/templates/firewall/nftables.j2
index fac3fad03..1f88ae40c 100644
--- a/data/templates/firewall/nftables.j2
+++ b/data/templates/firewall/nftables.j2
@@ -45,6 +45,14 @@ table ip filter {
         {{ conf | nft_default_rule(name_text) }}
     }
 {%     endfor %}
+{%     if group is vyos_defined and group.domain_group is vyos_defined %}
+{%         for name, name_config in group.domain_group.items() %}
+    set {{ name }} {
+        type ipv4_addr
+        flags interval
+    }
+{%         endfor %}
+{%     endif %}
 {%     for set_name in ns.sets %}
     set RECENT_{{ set_name }} {
         type ipv4_addr