From 640bd524ebbb38000c3ebcd41b940f6a6b81d80c Mon Sep 17 00:00:00 2001
From: Simon Polack <spolack+git@mailbox.org>
Date: Mon, 2 Dec 2024 23:00:47 +0100
Subject: [PATCH] Core/Gateway: Babel: add metrics for IPv4

---
 .../templates/corerouter/bird.conf.j2            | 16 +++++++++++++++-
 roles/cfg_openwrt/templates/gateway/bird.conf.j2 | 15 ++++++++++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/roles/cfg_openwrt/templates/corerouter/bird.conf.j2 b/roles/cfg_openwrt/templates/corerouter/bird.conf.j2
index 664029de0..c34cf3832 100644
--- a/roles/cfg_openwrt/templates/corerouter/bird.conf.j2
+++ b/roles/cfg_openwrt/templates/corerouter/bird.conf.j2
@@ -51,7 +51,21 @@ protocol babel {
 		};
 	};
 	ipv4 {
-		import all;
+		import filter {
+{% for nw in networks | selectattr('role', 'equalto', 'mesh') %}
+  {# metrics for 2 GHz adhoc get a penalty over 5 GHz adhoc so 5 GHz is preferred #}
+  {% set default_mesh_metric = hostvars[inventory_hostname].get('mesh_metric_adhoc_' ~ nw.get('mesh_radio'), mesh_metric_default_in) %}
+			if ifname = "{{ libnetwork.getIfname(nw) }}" then {
+			  babel_metric = babel_metric + {{  nw.get('mesh_metric', default_mesh_metric) }};
+			}
+{% endfor %}
+{% for nw in networks | selectattr('role', 'equalto', 'tunnel') %}
+			if ifname = "{{ nw.get('ifname') }}" then {
+			  babel_metric = babel_metric + {{  nw.get('mesh_metric', mesh_metric_tunnel_in) }};
+			}
+{% endfor %}
+			accept;
+		};
 		export where source = RTS_BABEL; # For now only advertise routes learned from babel
 	};
 
diff --git a/roles/cfg_openwrt/templates/gateway/bird.conf.j2 b/roles/cfg_openwrt/templates/gateway/bird.conf.j2
index ddcce1038..2b352eef7 100644
--- a/roles/cfg_openwrt/templates/gateway/bird.conf.j2
+++ b/roles/cfg_openwrt/templates/gateway/bird.conf.j2
@@ -97,7 +97,20 @@ protocol babel babel_mesh {
 	};
 	ipv4 {
 		table v4_main;
-		import where ifname !~ "gre4-*"; # Drop IPv4 routes learned via GRE, which remains a rather dirty hack for IPv6
+		import filter {
+			if ifname ~ "gre4-*" then reject;
+{% for interface in mesh_links %}
+			if ifname = "{{ interface['ifname'] }}" then {
+			  babel_metric = babel_metric + {{ interface.get('mesh_metric', mesh_metric_default_in) }};
+			  accept;
+			}
+{% endfor %}
+			if ifname ~ "wg_*" then {
+			  babel_metric = babel_metric + {{ mesh_metric_tunnel_in }};
+			  accept;
+			}
+			accept;
+		};
 		export where source = RTS_BABEL || net = 0.0.0.0/0; # Readvertise Babel routes and advertise default route
 	};