blobmsg_add_u32(&b, "metric", iface->metric);
blobmsg_add_u8(&b, "delegation", !iface->proto_ip.no_delegation);
a = blobmsg_open_array(&b, "ipv4-address");
blobmsg_add_u32(&b, "metric", iface->metric);
blobmsg_add_u8(&b, "delegation", !iface->proto_ip.no_delegation);
a = blobmsg_open_array(&b, "ipv4-address");