kay/router: add IPv6 support

1 files changed, 62 insertions, 3 deletions

diff --git a/os/kay/modules/router.nix b/os/kay/modules/router.nix
index daf4f63..d45b7c3 100644
--- a/os/kay/modules/router.nix
+++ b/os/kay/modules/router.nix
@@ -1,5 +1,6 @@
-{ ... }: let
+{ lib, pkgs, ... }: let
   wanInterface = "ppp0";
+  wanMTU = 1492;
 
   gponInterface = "enp3s0";
   gponHost = "192.168.38.1";
@@ -35,6 +36,11 @@ in {
           address = gponHost;
           prefixLength  = gponPrefix;
       }];
+      # TODO: fix it upstream
+      # https://github.com/NixOS/nixpkgs/blob/e8c38b73aeb218e27163376a2d617e61a2ad9b59/nixos/modules/services/networking/dhcpcd.nix#L13
+      # without this dhcpcd will not run, and if we set it to wanInterface,
+      # when pppd(ppp0 iface) exit it'll take out wan vlan iface as well
+      lo.useDHCP = true;
     };
     firewall = {
       allowedUDPPorts = [ 53 67 ];
@@ -50,10 +56,63 @@ in {
       '';
     };
   };
-
   services.dnsmasq.settings = {
     dhcp-range = [ "${leaseRangeStart},${leaseRangeEnd}" ];
-    dhcp-host= "${wapMac},${wapIp}";
+    dhcp-host = "${wapMac},${wapIp}";
     interface = [ lanInterface ];
   };
+
+  boot.kernel.sysctl."net.ipv6.conf.all.forwarding" = 2;
+  networking.dhcpcd = {
+    allowInterfaces = [ wanInterface ];
+    IPv6rs = false;
+    wait = "ipv6";
+    extraConfig = ''
+      ipv6only
+      interface ${wanInterface}
+        ipv6rs
+        ia_pd 1 ${lanInterface}/0
+    '';
+  };
+
+  # we start the services using pppd script
+  systemd.services = {
+    dhcpcd = {
+      before = lib.mkForce [];
+      wants = lib.mkForce [];
+      wantedBy = lib.mkForce [];
+    };
+    radvd = {
+      after = lib.mkForce [];
+      requires = lib.mkForce[];
+      wantedBy = lib.mkForce [];
+    };
+  };
+  services = {
+    pppd.script."ipv6" = {
+      runtimeInputs = [ pkgs.systemd pkgs.gnugrep pkgs.iproute2 ];
+      text = ''
+        systemctl restart dhcpcd.service
+        systemctl restart radvd.service
+      '';
+    };
+    radvd = {
+      enable = lib.mkForce true;
+      config = ''
+        interface ${lanInterface} {
+          AdvSendAdvert on;
+          AdvDefaultPreference high;
+          AdvLinkMTU ${toString wanMTU};
+
+          MinRtrAdvInterval 3;
+          MaxRtrAdvInterval 10;
+
+          prefix ::/64 {
+            AdvPreferredLifetime 60;
+            AdvValidLifetime 120;
+          };
+        };
+      '';
+    };
+  };
 }