network/nix/nixos-module/container/dnscache.nix

100 lines
3.4 KiB
Nix

{ hostName, config, lib, pkgs, ... }:
lib.mkIf config.site.hosts.${hostName}.services.dnscache.enable {
services.kresd = {
enable = true;
instances = 4;
listenPlain = [ "0.0.0.0:53" "[::0]:53" ];
package = pkgs.knot-resolver.override { extraFeatures = true; };
extraConfig = /* lua */ ''
modules = {
'http',
'policy',
'predict',
'prefill',
'serve_stale < cache', -- servce stail records while refreshing the record
'workarounds < iterate', -- solve problems around specific broken subdomains, mainly disables case randomization
'view'
}
cache.size = 500 * MB
cache.min_ttl(60)
net.listen('127.0.0.1', 8453, { kind = 'webmgmt' })
http.prometheus.namespace = 'resolver_'
-- dns42
policy.add(policy.suffix(
policy.STUB({'fd42:d42:d42:54::1', 'fd42:d42:d42:53::1', '172.20.0.53', '172.23.0.53'}),
policy.todnames({'dn42.', 'd.f.ip6.arpa', '20.172.in-addr.arpa', '21.172.in-addr.arpa', '22.172.in-addr.arpa', '23.172.in-addr.arpa'})
))
-- freifunk
policy.add(policy.suffix(
policy.STUB({'10.200.0.4', '10.200.0.16'}),
policy.todnames({'ffdd.', '200.10.in-addr.arpa', '201.10.in-addr.arpa'})
))
-- size.dns.localZones
policy.add(policy.suffix(
policy.STUB({'${config.site.net.serv.hosts4.dns}', ${lib.concatStringsSep ", " (map (hosts6: "'${hosts6.dns}'") (builtins.attrValues config.site.net.serv.hosts6))}}),
policy.todnames({${lib.concatStringsSep ", " (map (zone: "'${zone.name}'") config.site.dns.localZones)}})
))
-- forward to dns caches
policy.add(policy.slice(
policy.slice_randomize_psl(),
-- quad9
policy.TLS_FORWARD({
{'2620:fe::fe', hostname='dns.quad9.net'},
{'2620:fe::9', hostname='dns.quad9.net'},
{'9.9.9.9', hostname='dns.quad9.net'},
{'149.112.112.112', hostname='dns.quad9.net'}
}),
-- cloudflare
policy.TLS_FORWARD({
{'2606:4700:4700::1111', hostname='cloudflare-dns.com'},
{'2606:4700:4700::1001', hostname='cloudflare-dns.com'},
{'1.1.1.1', hostname='cloudflare-dns.com'},
{'1.0.0.1', hostname='cloudflare-dns.com'}
})
))
-- allow access from our networks
'' + lib.concatMapStringsSep "\n" (cidr: "view:addr('${cidr}', policy.all(policy.PASS))") [
# localhost
"::1/128" "127.0.0.0/8"
# mgmt
"${config.site.net.mgmt.subnet4}"
# dn42
"fd23:42:c3d2:500::/56" "::172.20.72.0/117" "::172.22.99.0/120"
"172.20.72.0/21" "172.22.99.0/24"
# freifunk
"10.200.0.0/15"
# DSI
"2a00:8180:2000:37::1/128" "2a00:8180:2c00:200::/56"
# flpk
"${config.site.net.flpk.subnet4}" "2a0f:5382:acab:1400::/56 allow"
] + "\n" + /* lua */ ''
-- drop everything that hasn't matched
view:addr('0.0.0.0/0', policy.all(policy.DROP))
view:addr('::/0', policy.all(policy.DROP))
predict = {
window = 15, -- sampling window
period = 24*(60/15) -- track last X hours, divide through sampling window
}
prefill.config({
['.'] = {
url = 'https://www.internic.net/domain/root.zone',
interval = 86400, -- seconds
}
})
trust_anchors.set_insecure({'dn42', 'd.f.ip6.arpa', 'ffdd'})
'';
};
}