log syslog all;
router id A.B.C.D;

define myas = myASN;
define linka = ASN1;
define linkb = ASN2;
define gatewaya = X.X.X.A;
define gatewayb = X.X.X.B;
table ispa;
table ispb;

protocol device
{
  scan time 10;
}

protocol static static_bgp {
  import all;

  route A.A.A.A/22 reject;
  route Y.Y.Y.A/29 reject;
  route Y.Y.Y.B/29 reject;
}

function net_local()
{
  return net ~ [ A.A.A.A/22+ ];
}

# Generic / Helper Functions / filters

function net_martian()
{
  return net ~ [ 169.254.0.0/16+, 172.16.0.0/12+, 192.168.0.0/16+, 10.0.0.0/8+, 127.0.0.0/8+, 224.0.0.0/4+, 240.0.0.0/4+, 0.0.0.0/32-, 0.0.0.0/0{25,32}, 0.0.0.0/0{0,7} ];
}

function rt_import()
int asn;
int set peer_asns;
prefix set peer_nets;
{
  if ! (net ~ peer_nets) then return false;
  if ! (bgp_path.last ~ peer_asns) then return false;
  if bgp_path.first != asn then return false;
  if bgp_path.len > 64 then return false;
  if bgp_next_hop != from then return false;
  return true; 
}

function rt_import_all(int asn)
{
  if net_martian() || net_local() then return false;
  if bgp_path.first != asn then return false;
  if bgp_path.len > 64 then return false;
  if bgp_next_hop != from then return false;
  return true;
}

function rt_export()
{
  if proto = "static_bgp" then return true;
  if source != RTS_BGP then return false;
  if net_martian() then return false;
  if bgp_path.len > 64 then return false;
  return bgp_path.first ~ [ myas ];
}

function rt_export_all()
{
  if proto = "static_bgp" then return true;
  if source != RTS_BGP then return false;
  if net_martian() then return false;
  if bgp_path.len > 64 then return false;
  return true;
}

### End Helper Functions


### BGP uplink A
protocol kernel k_a
{
  table ispa;
  export all;

  kernel table 1;
  scan time 15;
}

filter bgp_in_uplink_a
{ 
  if ! rt_import_all(linka) then reject;
  accept;
}

filter bgp_out_uplink_a
{
  if ! rt_export() then reject;

  # Routing policy: penalize routes that other people would
  # get to me through isp A
    bgp_path.prepend(myas);
    bgp_path.prepend(myas);
    bgp_path.prepend(myas);

  accept;
}

protocol pipe p_a
{
  table master;
  peer table ispa;
  import filter bgp_in_uplink_a;
  export filter bgp_out_uplink_a;
}

protocol bgp bgp_a
{
  table ispa;
  import all;
  export all;

  local as myas;
  neighbor gatewaya as linka;

  # Routing policy: make routes from uplinks less prefered
  default bgp_local_pref 50;
}

### BGP uplink B
protocol kernel k_b
{
  table ispb;
  export all;

  kernel table 2;
  scan time 15;
}

filter bgp_in_uplink_b
{ 
  if ! rt_import_all(linkb) then reject;
  accept;
}

filter bgp_out_uplink_b
{
  if ! rt_export() then reject;
  accept;
}

protocol pipe p_b
{
  table master;
  peer table ispb;
  import filter bgp_in_uplink_b;
  export filter bgp_out_uplink_b;
}

protocol bgp bgp_b
{
  table ispb;
  import all;
  export all;

  local as myas;
  neighbor gatewayb as linkb;
}

protocol static static_ospf {
  import all;

  route 0.0.0.0/0 reject;
}

protocol ospf {
  import all;
  export where proto = "static_ospf";

  export filter {
    ospf_metric1 = 1000;
    if source = RTS_STATIC then accept; else reject;
  };

  area 0 {
    interface "eth2" {
      cost 200;
      type pointopoint;
      hello 5; retransmit 2; wait 10; dead 20;
      };
    interface "eth5" {
      cost 5;
      type pointopoint;
      hello 5; retransmit 2; wait 10; dead 20;
      };
    interface "*" {
      cost 1000;
      stub;
      };
  };
}