function is_dn42_network() {
  return net ~ [
    172.20.0.0/14{21,29}, # dn42
    172.20.0.0/24{28,32}, # dn42 Anycast
    172.21.0.0/24{28,32}, # dn42 Anycast
    172.22.0.0/24{28,32}, # dn42 Anycast
    172.23.0.0/24{28,32}, # dn42 Anycast
    172.31.0.0/16+,       # ChaosVPN
    10.100.0.0/14+,       # ChaosVPN
    10.0.0.0/8{15,24}     # Freifunk.net
  ];
}

function is_dn42_network_v6() {
  return net ~ [
    fd00::/8{44,64} # ULA address space as per RFC 4193
  ];
}

roa4 table dn42_roa;
roa6 table dn42_roa_v6;

protocol static {
    roa4 { table dn42_roa; };
    include "/etc/bird/roa_dn42.conf";
};

protocol static {
    roa6 { table dn42_roa_v6; };
    include "/etc/bird/roa_dn42_v6.conf";
};

template bgp dnpeers {
    local as OWNAS;
    path metric 1;
    
    ipv4 {
        import filter {
          if is_dn42_network() && !is_self_net() then {
            if (roa_check(dn42_roa, net, bgp_path.last) != ROA_VALID) then {
              print "[dn42] ROA check failed for ", net, " ASN ", bgp_path.last;
              reject;
            } else accept;
          } else reject;
        };

        export filter { if is_dn42_network() then accept; else reject; };
        import limit 1000 action block;
    };

    ipv6 {
        import filter {
          if is_dn42_network_v6() && !is_self_net_v6() then {
            if (roa_check(dn42_roa_v6, net, bgp_path.last) != ROA_VALID) then {
              print "[dn42] ROA check failed for ", net, " ASN ", bgp_path.last;
              reject;
            } else accept;
          } else reject;
        };
        export filter { if is_dn42_network_v6() then accept; else reject; };
        import limit 1000 action block; 
    };
}

template bgp dnpeers_4only {
    local as OWNAS;
    path metric 1;

    ipv4 {
        import filter {
          if is_dn42_network() && !is_self_net() then {
            if (roa_check(dn42_roa, net, bgp_path.last) != ROA_VALID) then {
              print "[dn42] ROA check failed for ", net, " ASN ", bgp_path.last;
              reject;
            } else accept;
          } else reject;
        };

        export filter { if is_dn42_network() then accept; else reject; };
        import limit 1000 action block;
    };
}

template bgp dnpeers_6only {
    local as OWNAS;
    path metric 1;

    ipv6 {
        import filter {
          if is_dn42_network_v6() && !is_self_net_v6() then {
            if (roa_check(dn42_roa_v6, net, bgp_path.last) != ROA_VALID) then {
              print "[dn42] ROA check failed for ", net, " ASN ", bgp_path.last;
              reject;
            } else accept;
          } else reject;
        };
        export filter { if is_dn42_network_v6() then accept; else reject; };
        import limit 1000 action block;
    };
}