resolve: systemd set DNS names

src/resolve.c

@@ -25,6 +25,7 @@
 #endif
 
 #include <errno.h>
+#include <arpa/inet.h>
 
 #include <ell/ell.h>
 
@@ -48,16 +49,68 @@ struct resolve_method {
 static struct resolve_method method;
 
 #define SYSTEMD_RESOLVED_SERVICE           "org.freedesktop.resolve1"
+#define SYSTEMD_RESOLVED_MANAGER_PATH      "/org/freedesktop/resolve1"
+#define SYSTEMD_RESOLVED_MANAGER_INTERFACE "org.freedesktop.resolve1.Manager"
 
 struct systemd_state {
 	uint32_t service_watch;
 	bool is_ready:1;
 };
 
-static void resolve_systemd_add_dns(uint32_t ifindex, char **dns_list,
-								void *data)
+static void systemd_link_dns_reply(struct l_dbus_message *message,
+								void *user_data)
+{
+	const char *name;
+	const char *text;
+
+	if (!l_dbus_message_is_error(message))
+		return;
+
+	l_dbus_message_get_error(message, &name, &text);
+
+	l_error("resolve-systemd: Failed to modify the DNS entries. %s: %s",
+								name, text);
+}
+
+static bool systemd_builder_add_dns(struct l_dbus_message_builder *builder,
+						uint8_t type, const char *dns)
+{
+	uint8_t buf[16];
+	uint8_t buf_size;
+	uint8_t i;
+	int t = (int) type;
+
+	l_debug("installing DNS: %s %u", dns, type);
+
+	l_dbus_message_builder_append_basic(builder, 'i', &t);
+	l_dbus_message_builder_enter_array(builder, "y");
+
+	switch (type) {
+	case AF_INET:
+		if (inet_pton(AF_INET, dns, buf) < 1)
+			return false;
+
+		buf_size = 4;
+
+		break;
+	default:
+		return false;
+	}
+
+	for (i = 0; i < buf_size; i++)
+		l_dbus_message_builder_append_basic(builder, 'y', &buf[i]);
+
+	l_dbus_message_builder_leave_array(builder);
+
+	return true;
+}
+
+static void resolve_systemd_add_dns(uint32_t ifindex, uint8_t type,
+						char **dns_list, void *data)
 {
 	struct systemd_state *state = data;
+	struct l_dbus_message_builder *builder;
+	struct l_dbus_message *message;
 
 	l_debug("ifindex: %u", ifindex);
 
@@ -68,7 +121,48 @@ static void resolve_systemd_add_dns(uint32_t ifindex, char **dns_list,
 		return;
 	}
 
-	/* TODO */
+	message =
+		l_dbus_message_new_method_call(dbus_get_bus(),
+					SYSTEMD_RESOLVED_SERVICE,
+					SYSTEMD_RESOLVED_MANAGER_PATH,
+					SYSTEMD_RESOLVED_MANAGER_INTERFACE,
+					"SetLinkDNS");
+
+	if (!message)
+		return;
+
+	builder = l_dbus_message_builder_new(message);
+	if (!builder) {
+		l_dbus_message_unref(message);
+		return;
+	}
+
+	l_dbus_message_builder_append_basic(builder, 'i', &ifindex);
+
+	l_dbus_message_builder_enter_array(builder, "(iay)");
+
+	for (; *dns_list; dns_list++) {
+		l_dbus_message_builder_enter_struct(builder, "iay");
+
+		if (systemd_builder_add_dns(builder, type, *dns_list)) {
+			l_dbus_message_builder_leave_struct(builder);
+
+			continue;
+		}
+
+		l_dbus_message_builder_destroy(builder);
+		l_dbus_message_unref(message);
+
+		return;
+	}
+
+	l_dbus_message_builder_leave_array(builder);
+
+	l_dbus_message_builder_finalize(builder);
+	l_dbus_message_builder_destroy(builder);
+
+	l_dbus_send_with_reply(dbus_get_bus(), message, systemd_link_dns_reply,
+								state, NULL);
 }
 
 static void resolve_systemd_remove(uint32_t ifindex, void *data)