# This is forked from bird.cfg.template from calico running on k0.hswaw.net on 2020/09/21.
# Changed vs. upstream (C-f HSCLOUD):
#  - set 'passive on' on 127.0.0.1 neighbors, used for estabilishing connectivity
#    with metallb.
# Generated by confd
include "bird_aggr.cfg";
include "bird_ipam.cfg";

{{- $node_ip_key := printf "/host/%s/ip_addr_v4" (getenv "NODENAME")}}{{$node_ip := getv $node_ip_key}}
{{- $router_id := getenv "CALICO_ROUTER_ID" ""}}

{{- $node_name := getenv "NODENAME"}}

router id {{if eq "hash" ($router_id) -}}
	{{hashToIPv4 $node_name}};
{{- else -}}
	{{if ne "" ($router_id)}}{{$router_id}}{{else}}{{$node_ip}}{{end}};
{{- end}}

{{- define "LOGGING"}}
{{- $node_logging_key := printf "/host/%s/loglevel" (getenv "NODENAME")}}
{{- if exists $node_logging_key}}
{{- $logging := getv $node_logging_key}}
{{- if eq $logging "debug"}}
  debug all;
{{- else if ne $logging "none"}}
  debug { states };
{{- end}}
{{- else if exists "/global/loglevel"}}
{{- $logging := getv "/global/loglevel"}}
{{- if eq $logging "debug"}}
  debug all;
{{- else if ne $logging "none"}}
  debug { states };
{{- end}}
{{- else}}
  debug { states };
{{- end}}
{{- end}}

# Configure synchronization between routing tables and kernel.
protocol kernel {
  learn;             # Learn all alien routes from the kernel
  persist;           # Don't remove routes on bird shutdown
  scan time 2;       # Scan kernel routing table every 2 seconds
  import all;
  export filter calico_kernel_programming; # Default is export none
  graceful restart;  # Turn on graceful restart to reduce potential flaps in
                     # routes when reloading BIRD configuration.  With a full
                     # automatic mesh, there is no way to prevent BGP from
                     # flapping since multiple nodes update their BGP
                     # configuration at the same time, GR is not guaranteed to
                     # work correctly in this scenario.
}

# Watch interface up/down events.
protocol device {
{{- template "LOGGING"}}
  scan time 2;    # Scan interfaces every 2 seconds
}

protocol direct {
{{- template "LOGGING"}}
  interface -"cali*", -"kube-ipvs*", "*"; # Exclude cali* and kube-ipvs* but
                                          # include everything else.  In
                                          # IPVS-mode, kube-proxy creates a
                                          # kube-ipvs0 interface. We exclude
                                          # kube-ipvs0 because this interface
                                          # gets an address for every in use
                                          # cluster IP. We use static routes
                                          # for when we legitimately want to
                                          # export cluster IPs.
}

{{if eq "" ($node_ip)}}# IPv4 disabled on this node.
{{else}}{{$node_as_key := printf "/host/%s/as_num" (getenv "NODENAME")}}
# Template for all BGP clients
template bgp bgp_template {
{{- $as_key := or (and (exists $node_as_key) $node_as_key) "/global/as_num"}}
{{- $node_as_num := getv $as_key}}
{{- template "LOGGING"}}
  description "Connection to BGP peer";
  local as {{$node_as_num}};
  multihop;
  gateway recursive; # This should be the default, but just in case.
  import all;        # Import all routes, since we don't know what the upstream
                     # topology is and therefore have to trust the ToR/RR.
  export filter calico_export_to_bgp_peers;  # Only want to export routes for workloads.
  source address {{$node_ip}};  # The local address we use for the TCP connection
  add paths on;
  graceful restart;  # See comment in kernel section about graceful restart.
  connect delay time 2;
  connect retry time 5;
  error wait time 5,30;
}

# ------------- Node-to-node mesh -------------
{{- $node_cid_key := printf "/host/%s/rr_cluster_id" (getenv "NODENAME")}}
{{- $node_cluster_id := getv $node_cid_key}}
{{if (json (getv "/global/node_mesh")).enabled}}
{{range $host := lsdir "/host"}}
{{$onode_as_key := printf "/host/%s/as_num" .}}
{{$onode_ip_key := printf "/host/%s/ip_addr_v4" .}}{{if exists $onode_ip_key}}{{$onode_ip := getv $onode_ip_key}}
{{$nums := split $onode_ip "."}}{{$id := join $nums "_"}}
# For peer {{$onode_ip_key}}
{{if eq $onode_ip ($node_ip) }}# Skipping ourselves ({{$node_ip}})
{{else if ne "" $onode_ip}}protocol bgp Mesh_{{$id}} from bgp_template {
  neighbor {{$onode_ip}} as {{if exists $onode_as_key}}{{getv $onode_as_key}}{{else}}{{getv "/global/as_num"}}{{end}};
  {{- /*
       Make the peering unidirectional. This avoids a race where
       - peer A opens a connection and begins a graceful restart
       - before the restart completes, peer B opens its connection
       - peer A sees the new connection and aborts the graceful restart, causing a route flap.
  */ -}}
  {{if gt $onode_ip $node_ip}}
  passive on; # Mesh is unidirectional, peer will connect to us. 
  {{- end}}
}{{end}}{{end}}{{end}}
{{else}}
# Node-to-node mesh disabled
{{end}}


# ------------- Global peers -------------
{{if ls "/global/peer_v4"}}
{{range gets "/global/peer_v4/*"}}{{$data := json .Value}}
{{$nums := split $data.ip "."}}{{$id := join $nums "_"}}
# For peer {{.Key}}
{{- if eq $data.ip ($node_ip) }}
# Skipping ourselves ({{$node_ip}})
{{- else}}
protocol bgp Global_{{$id}} from bgp_template {
  {{if eq $data.ip ("127.0.0.1")}}passive on; # HSCLOUD {{end}}
  neighbor {{$data.ip}} as {{$data.as_num}};
{{- if and (eq $data.as_num $node_as_num) (ne "" ($node_cluster_id)) (ne $data.rr_cluster_id ($node_cluster_id))}}
  rr client;
  rr cluster id {{$node_cluster_id}};
{{- end}}
}
{{- end}}
{{end}}
{{else}}# No global peers configured.{{end}}


# ------------- Node-specific peers -------------
{{$node_peers_key := printf "/host/%s/peer_v4" (getenv "NODENAME")}}
{{if ls $node_peers_key}}
{{range gets (printf "%s/*" $node_peers_key)}}{{$data := json .Value}}
{{$nums := split $data.ip "."}}{{$id := join $nums "_"}}
# For peer {{.Key}}
{{- if eq $data.ip ($node_ip) }}
# Skipping ourselves ({{$node_ip}})
{{- else}}
protocol bgp Node_{{$id}} from bgp_template {
  neighbor {{$data.ip}} as {{$data.as_num}};
{{- if and (eq $data.as_num $node_as_num) (ne "" ($node_cluster_id)) (ne $data.rr_cluster_id ($node_cluster_id))}}
  rr client;
  rr cluster id {{$node_cluster_id}};
{{- end}}
}
{{- end}}
{{end}}
{{else}}# No node-specific peers configured.{{end}}
{{end}}{{/* End of IPv4 enable check */}}