qubes-mirage-firewall/unikernel.ml
2024-10-15 21:36:30 +02:00

118 lines
4.7 KiB
OCaml

(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Lwt
open Qubes
open Cmdliner
let src = Logs.Src.create "unikernel" ~doc:"Main unikernel code"
module Log = (val Logs.src_log src : Logs.LOG)
let nat_table_size =
let doc = Arg.info ~doc:"The number of NAT entries to allocate." [ "nat-table-size" ] in
Mirage_runtime.register_arg Arg.(value & opt int 5_000 doc)
let ipv4 =
let doc = Arg.info ~doc:"Manual IP setting." [ "ipv4" ] in
Mirage_runtime.register_arg Arg.(value & opt string "0.0.0.0" doc)
let ipv4_gw =
let doc = Arg.info ~doc:"Manual Gateway IP setting." [ "ipv4-gw" ] in
Mirage_runtime.register_arg Arg.(value & opt string "0.0.0.0" doc)
let ipv4_dns =
let doc = Arg.info ~doc:"Manual DNS IP setting." [ "ipv4-dns" ] in
Mirage_runtime.register_arg Arg.(value & opt string "10.139.1.1" doc)
let ipv4_dns2 =
let doc = Arg.info ~doc:"Manual Second DNS IP setting." [ "ipv4-dns2" ] in
Mirage_runtime.register_arg Arg.(value & opt string "10.139.1.2" doc)
module Main (R : Mirage_crypto_rng_mirage.S)(Clock : Mirage_clock.MCLOCK)(Time : Mirage_time.S) = struct
module Dispatcher = Dispatcher.Make(R)(Clock)(Time)
module Dns_transport = My_dns.Transport(R)(Clock)(Time)
module Dns_client = Dns_client.Make(Dns_transport)
(* Set up networking and listen for incoming packets. *)
let network dns_client dns_responses dns_servers qubesDB router =
(* Report success *)
Dao.set_iptables_error qubesDB "" >>= fun () ->
(* Handle packets from both networks *)
Lwt.choose [
Dispatcher.wait_clients Clock.elapsed_ns dns_client dns_servers qubesDB router ;
Dispatcher.uplink_wait_update qubesDB router ;
Dispatcher.uplink_listen Clock.elapsed_ns dns_responses router
]
(* Main unikernel entry point (called from auto-generated main.ml). *)
let start _random _clock _time =
let open Lwt.Syntax in
let start_time = Clock.elapsed_ns () in
(* Start qrexec agent and QubesDB agent in parallel *)
let* qrexec = RExec.connect ~domid:0 () in
let agent_listener = RExec.listen qrexec Command.handler in
let* qubesDB = DB.connect ~domid:0 () in
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 =
Xen_os.Lifecycle.await_shutdown_request () >>= fun (`Poweroff | `Reboot) ->
Lwt.return_unit in
(* Set up networking *)
let nat = My_nat.create ~max_entries:(nat_table_size ()) in
let netvm_ip = Ipaddr.V4.of_string_exn (ipv4_gw ()) in
let our_ip = Ipaddr.V4.of_string_exn (ipv4 ()) in
let dns = Ipaddr.V4.of_string_exn (ipv4_dns ()) in
let dns2 = Ipaddr.V4.of_string_exn (ipv4_dns2 ()) in
let zero_ip = Ipaddr.V4.any in
let network_config =
if (netvm_ip = zero_ip && our_ip = zero_ip) then (* Read network configuration from QubesDB *)
Dao.read_network_config qubesDB >>= fun config ->
if config.netvm_ip = zero_ip || config.our_ip = zero_ip then
Log.info (fun f -> f "We currently have no netvm nor command line for setting it up, aborting...");
assert (config.netvm_ip <> zero_ip && config.our_ip <> zero_ip);
Lwt.return config
else begin
let config:Dao.network_config = {from_cmdline=true; netvm_ip; our_ip; dns; dns2} in
Lwt.return config
end
in
network_config >>= fun config ->
(* We now must have a valid netvm IP address and our IP address or crash *)
Dao.print_network_config config ;
(* Set up client-side networking *)
let* clients = Client_eth.create config in
(* Set up routing between networks and hosts *)
let router = Dispatcher.create
~config
~clients
~nat
~uplink:None
in
let send_dns_query = Dispatcher.send_dns_client_query router in
let dns_mvar = Lwt_mvar.create_empty () in
let nameservers = `Udp, [ config.Dao.dns, 53 ; config.Dao.dns2, 53 ] in
let dns_client = Dns_client.create ~nameservers (router, send_dns_query, dns_mvar) in
let dns_servers = [ config.Dao.dns ; config.Dao.dns2 ] in
let net_listener = network (Dns_client.getaddrinfo dns_client Dns.Rr_map.A) dns_mvar dns_servers 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. *)
Time.sleep_ns (1.0 *. 1e9 |> Int64.of_float)
end