Add ip-service-type

For setting up custom networks with ip -batch.

services/ip.scm

@@ -0,0 +1,35 @@
+(define-module (services ip)
+  #:use-module (gnu packages linux)
+  #:use-module (gnu services)
+  #:use-module (gnu services shepherd)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:use-module (ice-9 match)
+  #:export (ip-shepherd-service ip-configuration))
+
+(define-record-type* <ip-configuration>
+  ip-configuration make-ip-configuration ip-configuration?
+  (package ip-configuration-package (default iproute))
+  (commands ip-configuration-commands (default '())))
+
+(define ip-shepherd-service
+  (match-lambda
+    (($ <ip-configuration> package commands)
+     (list
+      (shepherd-service
+       (provision '(ip))
+       (documentation (format #f "Run iproute2 commands."))
+       (one-shot? #t)
+       (start
+        #~(lambda _
+            (system* (string-append #$package "/sbin/ip") "-batch"
+                     #$(plain-file "ip" (string-join commands "\n"))))))))))
+
+(define-public ip-service-type
+  (service-type
+   (name 'ip)
+   (extensions
+    (list
+     (service-extension shepherd-root-service-type ip-shepherd-service)))
+   (description "Run the given list of iproute2 commands.")
+   (default-value (ip-configuration))))