From 2420018235cf74285c2df68dba1d9f9272ed26a4 Mon Sep 17 00:00:00 2001
From: Luke Granger-Brown <hg@lukegb.com>
Date: Sat, 30 Sep 2023 01:14:36 +0000
Subject: [PATCH] etheroute-lon01: change setup of quadv

---
 ops/nixos/etheroute-lon01/default.nix | 52 +++++++++------------------
 ops/nixos/lib/bgp.nix                 | 26 +++++++++-----
 2 files changed, 34 insertions(+), 44 deletions(-)

diff --git a/ops/nixos/etheroute-lon01/default.nix b/ops/nixos/etheroute-lon01/default.nix
index 3387f2d289..da2f65c1af 100644
--- a/ops/nixos/etheroute-lon01/default.nix
+++ b/ops/nixos/etheroute-lon01/default.nix
@@ -116,6 +116,9 @@
       # Accept from "trusted" quadv1 interface
       ip46tables -A lukegb-forward -i quadv1 -j lukegb-fwd-accept
 
+      # Accept to quadv1 interface if we're multipathing.
+      ip46tables -A lukegb-forward -o quadv1 -j lukegb-fwd-accept
+
       # Accept from established/related connections.
       ip46tables -A lukegb-forward -m conntrack --ctstate ESTABLISHED,RELATED -j lukegb-fwd-accept
 
@@ -158,26 +161,6 @@
     }];
   };
 
-  systemd.network.netdevs.gsl1 = {
-    netdevConfig = {
-      Name = "gsl1";
-      Kind = "vxlan";
-    };
-
-    vxlanConfig = {
-      VNI = 242;
-      Remote = "203.57.82.5";
-      Local = "103.141.25.50";
-      DestinationPort = 4789;
-    };
-  };
-  systemd.network.networks."40-eno1".vxlan = [ "gsl1" ];
-  systemd.network.networks.gsl1 = {
-    matchConfig.Name = "gsl1";
-    address = [ "10.0.0.22/30" "2401:3bc0::4:16/126" ];
-  };
-
-
   services.openssh.hostKeys = [
     {
       path = "/persist/etc/ssh/ssh_host_ed25519_key";
@@ -202,7 +185,6 @@
       local = {
         routerID = "103.141.25.50";
       };
-      export.v4 = [ "92.118.31.0/24" ];
       peering = {
         etheroute = {
           local = local // {
@@ -218,20 +200,6 @@
             }];
           };
         };
-        gsl = {
-          local = local // {
-            v4 = "10.0.0.22";
-            v6 = "2401:3bc0::4:16";
-          };
-          remote = {
-            asn = 137409;
-            export_community = 4002;
-            routers = [{
-              v4 = "10.0.0.21";
-              v6 = "2401:3bc0::4:15";
-            }];
-          };
-        };
         bgptoolscollector = {
           local = local // {
             v4 = "103.141.25.50";
@@ -250,6 +218,20 @@
             prefix_limit.v6 = 0;
           };
         };
+        quadv = {
+          local = local // {
+            v4 = "169.254.111.0";
+          };
+          remote = {
+            asn = 197753;
+            export_community = 4099;
+            routers = [{
+              v4 = "169.254.111.1";
+            }];
+            prefix_limit.v4 = 10;
+            prefix_limit.v6 = 10;
+          };
+        };
       };
     };
   };
diff --git a/ops/nixos/lib/bgp.nix b/ops/nixos/lib/bgp.nix
index 27f4be7b5e..d20d29772c 100644
--- a/ops/nixos/lib/bgp.nix
+++ b/ops/nixos/lib/bgp.nix
@@ -16,6 +16,16 @@ let
       ${if ix.remote.must_be_next_hop then "if (bgp_path.first != ${toString ix.remote.asn}) then reject;" else "# no next-hop requirement"}
       ${lib.concatMapStringsSep "\n" (asn: "if (bgp_path ~ [= * ${toString asn} * =]) then reject;") ix.remote.drop_asns}
       if (bgp_path ~ [= * 16276 * =] && gw = 195.66.225.6) then gw = 195.66.224.220;  # OVH must go via router 1; router 2 is bork.
+      ${lib.optionalString (ixName == "quadv") ''
+        bgp_ext_community.add((ro, 205479, 1000));
+        bgp_ext_community.add((ro, 205479, 4000));  # etheroute
+        #bgp_ext_community.add((ro, 205479, 4002));  # gsl
+
+        # Etheroute communities
+        bgp_community.add((3170, 63257));  # GTT Corero
+        bgp_community.add((64600, 3356));  # no Lumen
+        bgp_community.add((64600, 5459));  # no LINX peers (inc. RS)
+      ''}
       bgp_local_pref = ${toString ix.remote.bgp_local_pref};
       accept;
     }
@@ -33,6 +43,7 @@ let
     };
     ''}
 
+    ${lib.optionalString (doesIPv6 ix) ''
     ipv6 table ${ixName}6;
     filter bgp_in_${ixName}6
     prefix set allnet;
@@ -57,8 +68,10 @@ let
       import ${if ix.remote.is_route_collector then "all" else "where ((ro, ${toString ix.local.asn}, ${toString ix.remote.export_community}) ~ bgp_ext_community)"};
       export filter bgp_in_${ixName}6;
     };
+    ''}
   '' + lib.concatImapStringsSep "\n" ( i: v: generateSnippetForRouter (args // { routerNum = i; router = v; }) ) ix.remote.routers;
   doesIPv4 = ix: (ix.local.v4 != null) || ix.v4onv6;
+  doesIPv6 = ix: (ix.local.v6 != null);
   enabledSnippet = { enabled ? true, ... }: "disabled ${if enabled then "off" else "on"};";
   passwordSnippet = { password ? null, ... }: if password == null then "# no password" else "password \"${password}\";";
   multihopSnippet = { multihop ? null, ... }: if multihop == null then "# not multihop" else "multihop ${toString multihop};";
@@ -83,6 +96,7 @@ let
       };
     };
     ''}
+    ${lib.optionalString (ix.local.v6 != null) ''
     protocol bgp ${ixName}${toString routerNum}_6 {
       ${enabledSnippet router}
       ${passwordSnippet router}
@@ -108,6 +122,7 @@ let
         ${prefixLimitSnippet ix.remote.prefix_limit.v6}
       };
     };
+    ''}
   '';
 
   inherit (lib) mkOption mkAfter types;
@@ -143,7 +158,8 @@ in {
                         default = null;
                       };
                       v6 = mkOption { # lukegbgp.config.peering.<foo>.local.v6
-                        type = str;
+                        type = nullOr str;
+                        default = null;
                       };
                     };
                   };
@@ -325,14 +341,6 @@ in {
         protocol static export4 {
           ipv4 {
             import filter {
-
-              if net = 92.118.31.0/24 then {
-                # bgp_path.prepend(197753);
-                bgp_ext_community.add((ro, 205479, 1000));
-                bgp_ext_community.add((ro, 205479, 4002));
-                accept;
-              }
-
               bgp_ext_community.add((ro, 205479, 1000));
               bgp_ext_community.add((ro, 205479, 2000));
               bgp_ext_community.add((ro, 205479, 2001));