add openvswitch package + basic nixos module to enable it

1 files changed, 120 insertions, 0 deletions

diff --git a/nixos/modules/virtualisation/openvswitch.nix b/nixos/modules/virtualisation/openvswitch.nix
new file mode 100644
index 000000000000..2070dd0f7839
--- /dev/null
+++ b/nixos/modules/virtualisation/openvswitch.nix
@@ -0,0 +1,120 @@
+# Systemd services for openvswitch
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+    cfg = config.virtualisation.vswitch;
+
+in
+
+{
+    # ------------------------------------------------------------
+
+    options = {
+
+        virtualisation.vswitch.enable = mkOption {
+            type = types.bool;
+            default = false;
+            description =
+                ''
+                Enable Open vSwitch. A configuration 
+                daemon (ovs-server) will be started.
+                '';
+        };
+
+
+        virtualisation.vswitch.package = mkOption {
+            type = types.package;
+            default = pkgs.openvswitch;
+            description =
+                ''
+                Open vSwitch package to use.
+                '';
+        };
+
+    };
+
+    # ------------------------------------------------------------
+
+    config = mkIf cfg.enable (let 
+
+        # Where the communication sockets live
+        runDir = "/var/run/openvswitch";
+
+        # Where the config database live (can't be in nix-store)
+        stateDir = "/var/db/openvswitch";
+
+        # The path to the an initialized version of the database 
+        db = pkgs.stdenv.mkDerivation {
+            name = "vswitch.db";
+            unpackPhase = "true";
+            buildPhase = "true";
+            buildInputs = with pkgs; [
+                cfg.package
+            ];
+            installPhase = 
+                ''
+                ensureDir $out/
+                '';
+        };
+
+    in {
+
+        environment.systemPackages = [ cfg.package ]; 
+
+        boot.kernelModules = [ "tun" "openvswitch" ];
+
+        boot.extraModulePackages = [ cfg.package ];
+
+        systemd.services.ovsdb = {
+            description = "Open_vSwitch Database Server";
+            wantedBy = [ "multi-user.target" ];
+            after = [ "systemd-udev-settle.service" ];
+            wants = [ "vswitchd.service" ];
+            path = [ cfg.package ];
+            restartTriggers = [ db cfg.package ];
+            # Create the config database
+            preStart = 
+                ''
+                mkdir -p ${runDir}
+                mkdir -p /var/db/openvswitch
+                chmod +w /var/db/openvswitch
+                if [[ ! -e /var/db/openvswitch/conf.db ]]; then
+                    ${cfg.package}/bin/ovsdb-tool create \
+                        "/var/db/openvswitch/conf.db" \
+                        "${cfg.package}/share/openvswitch/vswitch.ovsschema"
+                fi
+                chmod -R +w /var/db/openvswitch
+                '';
+            serviceConfig.ExecStart = 
+                ''
+                ${cfg.package}/bin/ovsdb-server \
+                    --remote=punix:${runDir}/db.sock \
+                    --private-key=db:Open_vSwitch,SSL,private_key \
+                    --certificate=db:Open_vSwitch,SSL,certificate \
+                    --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert \
+                    --unixctl=ovsdb.ctl.sock \
+                    /var/db/openvswitch/conf.db
+                '';                
+            serviceConfig.Restart = "always";
+            serviceConfig.RestartSec = 3;
+            postStart =
+                ''
+                ${cfg.package}/bin/ovs-vsctl --timeout 3 --retry --no-wait init
+                '';
+
+        };
+
+        systemd.services.vswitchd = {
+            description = "Open_vSwitch Daemon";
+            bindsTo = [ "ovsdb.service" ];
+            after = [ "ovsdb.service" ];
+            path = [ cfg.package ];
+            serviceConfig.ExecStart = ''${cfg.package}/bin/ovs-vswitchd'';
+        };
+
+    });
+
+}