dockerd: Added option to set dns servers

* The default server is the default switch so that
  queries will go through the hosts dnsmasq by default

Signed-off-by: Gerard Ryan <G.M0N3Y.2503@gmail.com>

utils/dockerd/files/dockerd.init

@@ -142,6 +142,7 @@ process_config() {
 	config_get bip globals bip ""
 	config_get registry_mirrors globals registry_mirrors ""
 	config_get hosts globals hosts ""
+	config_get dns globals dns ""
 
 	. /usr/share/libubox/jshn.sh
 	json_init
@@ -155,6 +156,9 @@ process_config() {
 	[ -z "${hosts}" ] || json_add_array "hosts"
 	[ -z "${hosts}" ] || config_list_foreach globals hosts json_add_array_string
 	[ -z "${hosts}" ] || json_close_array
+	[ -z "${dns}" ] || json_add_array "dns"
+	[ -z "${dns}" ] || config_list_foreach globals dns json_add_array_string
+	[ -z "${dns}" ] || json_close_array
 	json_dump > "${DOCKERD_CONF}"
 
 	[ "${iptables}" -eq "1" ] && config_foreach iptables_add_blocking_rule firewall

utils/dockerd/files/etc/config/dockerd

@@ -11,6 +11,7 @@ config globals 'globals'
 	option iptables '1'
 #	list hosts 'unix:///var/run/docker.sock'
 #	option bip '172.18.0.1/24'
+#	list dns '172.17.0.1'
 #	list registry_mirrors 'https://<my-docker-mirror-host>'
 #	list registry_mirrors 'https://hub.docker.com'