1 files changed, 131 insertions, 0 deletions
diff --git a/nixos/modules/services/networking/dhcpd.nix b/nixos/modules/services/networking/dhcpd.nix
new file mode 100644
index 00000000000..43e0843cb97
--- /dev/null
+++ b/nixos/modules/services/networking/dhcpd.nix
@@ -0,0 +1,131 @@
+{ config, pkgs, ... }:
+
+with pkgs.lib;
+
+let
+
+  cfg = config.services.dhcpd;
+
+  stateDir = "/var/lib/dhcp"; # Don't use /var/state/dhcp; not FHS-compliant.
+
+  configFile = if cfg.configFile != null then cfg.configFile else pkgs.writeText "dhcpd.conf"
+    ''
+      default-lease-time 600;
+      max-lease-time 7200;
+      authoritative;
+      ddns-update-style ad-hoc;
+      log-facility local1; # see dhcpd.nix
+      
+      ${cfg.extraConfig}
+
+      ${pkgs.lib.concatMapStrings
+          (machine: ''
+            host ${machine.hostName} {
+              hardware ethernet ${machine.ethernetAddress};
+              fixed-address ${machine.ipAddress};
+            }
+          '')
+          cfg.machines
+      }
+    '';
+
+in
+  
+{
+
+  ###### interface
+
+  options = {
+  
+    services.dhcpd = {
+
+      enable = mkOption {
+        default = false;
+        description = "
+          Whether to enable the DHCP server.
+        ";
+      };
+
+      extraConfig = mkOption {
+        default = "";
+        example = "
+          option subnet-mask 255.255.255.0;
+          option broadcast-address 192.168.1.255;
+          option routers 192.168.1.5;
+          option domain-name-servers 130.161.158.4, 130.161.33.17, 130.161.180.1;
+          option domain-name \"example.org\";
+          subnet 192.168.1.0 netmask 255.255.255.0 {
+            range 192.168.1.100 192.168.1.200;
+          }
+        ";
+        description = "
+          Extra text to be appended to the DHCP server configuration
+          file.  Currently, you almost certainly need to specify
+          something here, such as the options specifying the subnet
+          mask, DNS servers, etc.
+        ";
+      };
+
+      configFile = mkOption {
+        default = null;
+        description = "
+          The path of the DHCP server configuration file.  If no file
+          is specified, a file is generated using the other options.
+        ";
+      };
+
+      interfaces = mkOption {
+        default = ["eth0"];
+        description = "
+          The interfaces on which the DHCP server should listen.
+        ";
+      };
+
+      machines = mkOption {
+        default = [];
+        example = [
+          { hostName = "foo";
+            ethernetAddress = "00:16:76:9a:32:1d";
+            ipAddress = "192.168.1.10";
+          }
+          { hostName = "bar";
+            ethernetAddress = "00:19:d1:1d:c4:9a";
+            ipAddress = "192.168.1.11";
+          }
+        ];
+        description = "
+          A list mapping ethernet addresses to IP addresses for the
+          DHCP server.
+        ";
+      };
+
+    };
+    
+  };
+  
+
+  ###### implementation
+
+  config = mkIf config.services.dhcpd.enable {
+
+    jobs.dhcpd =
+      { description = "DHCP server";
+
+        startOn = "started network-interfaces";
+        stopOn = "stopping network-interfaces";
+
+        script =
+          ''
+            mkdir -m 755 -p ${stateDir}
+
+            touch ${stateDir}/dhcpd.leases
+
+            exec ${pkgs.dhcp}/sbin/dhcpd -f -cf ${configFile} \
+                -lf ${stateDir}/dhcpd.leases \
+                ${toString cfg.interfaces}
+          '';
+      };
+
+  };
+  
+}