qubes-mirage-firewall/unikernel.ml

96 lines
3.5 KiB
OCaml

(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Lwt
open Qubes
let src = Logs.Src.create "unikernel" ~doc:"Main unikernel code"
module Log = (val Logs.src_log src : Logs.LOG)
module Main (R : Mirage_random.S)(Clock : Mirage_clock.MCLOCK) = struct
module Uplink = Uplink.Make(R)(Clock)
module Dns_transport = My_dns.Transport(R)(Clock)
module Dns_client = Dns_client.Make(Dns_transport)
(* Set up networking and listen for incoming packets. *)
let network dns_client dns_responses uplink qubesDB router =
(* Report success *)
Dao.set_iptables_error qubesDB "" >>= fun () ->
(* Handle packets from both networks *)
Lwt.choose [
Client_net.listen Clock.elapsed_ns dns_client qubesDB router;
Uplink.listen uplink Clock.elapsed_ns dns_responses router
]
(* We don't use the GUI, but it's interesting to keep an eye on it.
If the other end dies, don't let it take us with it (can happen on logout). *)
let watch_gui gui =
Lwt.async (fun () ->
Lwt.try_bind
(fun () ->
gui >>= fun gui ->
Log.info (fun f -> f "GUI agent connected");
GUI.listen gui ()
)
(fun `Cant_happen -> assert false)
(fun ex ->
Log.warn (fun f -> f "GUI thread failed: %s" (Printexc.to_string ex));
Lwt.return_unit
)
)
(* Main unikernel entry point (called from auto-generated main.ml). *)
let start _random _clock =
let start_time = Clock.elapsed_ns () in
(* Start qrexec agent, GUI agent and QubesDB agent in parallel *)
let qrexec = RExec.connect ~domid:0 () in
GUI.connect ~domid:0 () |> watch_gui;
let qubesDB = DB.connect ~domid:0 () in
(* Wait for clients to connect *)
qrexec >>= fun qrexec ->
let agent_listener = RExec.listen qrexec Command.handler in
qubesDB >>= fun qubesDB ->
let startup_time =
let (-) = Int64.sub in
let time_in_ns = Clock.elapsed_ns () - start_time in
Int64.to_float time_in_ns /. 1e9
in
Log.info (fun f -> f "QubesDB and qrexec agents connected in %.3f s" startup_time);
(* Watch for shutdown requests from Qubes *)
let shutdown_rq =
OS.Lifecycle.await_shutdown_request () >>= fun (`Poweroff | `Reboot) ->
Lwt.return_unit in
(* Set up networking *)
let max_entries = Key_gen.nat_table_size () in
My_nat.create ~max_entries >>= fun nat ->
(* Read network configuration from QubesDB *)
Dao.read_network_config qubesDB >>= fun config ->
Uplink.connect config >>= fun uplink ->
(* Set up client-side networking *)
let client_eth = Client_eth.create
~client_gw:config.Dao.clients_our_ip in
(* Set up routing between networks and hosts *)
let router = Router.create
~client_eth
~uplink:(Uplink.interface uplink)
~nat
in
let send_dns_query = Uplink.send_dns_client_query uplink in
let dns_mvar = Lwt_mvar.create_empty () in
let nameservers = `Udp, [ config.Dao.dns, 53 ] in
let dns_client = Dns_client.create ~nameservers (router, send_dns_query, dns_mvar) in
let net_listener = network (Dns_client.getaddrinfo dns_client Dns.Rr_map.A) dns_mvar uplink qubesDB router in
(* Report memory usage to XenStore *)
Memory_pressure.init ();
(* Run until something fails or we get a shutdown request. *)
Lwt.choose [agent_listener; net_listener; shutdown_rq] >>= fun () ->
(* Give the console daemon time to show any final log messages. *)
OS.Time.sleep_ns (1.0 *. 1e9 |> Int64.of_float)
end