qubes-mirage-firewall/uplink.ml
2020-01-13 09:54:09 +00:00

73 lines
2.3 KiB
OCaml

(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Lwt.Infix
open Fw_utils
module Eth = Ethernet.Make(Netif)
let src = Logs.Src.create "uplink" ~doc:"Network connection to NetVM"
module Log = (val Logs.src_log src : Logs.LOG)
module Arp = Arp.Make(Eth)(OS.Time)
type t = {
net : Netif.t;
eth : Eth.t;
arp : Arp.t;
interface : interface;
fragments : Fragments.Cache.t;
}
class netvm_iface eth mac ~my_ip ~other_ip : interface = object
val queue = FrameQ.create (Ipaddr.V4.to_string other_ip)
method my_mac = Eth.mac eth
method my_ip = my_ip
method other_ip = other_ip
method writev ethertype fillfn =
FrameQ.send queue (fun () ->
mac >>= fun dst ->
Eth.write eth dst ethertype fillfn >|= or_raise "Write to uplink" Eth.pp_error
)
end
let listen t get_ts router =
Netif.listen t.net ~header_size:Ethernet_wire.sizeof_ethernet (fun frame ->
(* Handle one Ethernet frame from NetVM *)
Eth.input t.eth
~arpv4:(Arp.input t.arp)
~ipv4:(fun ip ->
match Nat_packet.of_ipv4_packet t.fragments ~now:(get_ts ()) ip with
| exception ex ->
Log.err (fun f -> f "Error unmarshalling ethernet frame from uplink: %s@.%a" (Printexc.to_string ex)
Cstruct.hexdump_pp frame
);
Lwt.return_unit
| Error e ->
Log.warn (fun f -> f "Ignored unknown IPv4 message from uplink: %a" Nat_packet.pp_error e);
Lwt.return_unit
| Ok None -> Lwt.return_unit
| Ok (Some packet) ->
Firewall.ipv4_from_netvm router packet
)
~ipv6:(fun _ip -> Lwt.return_unit)
frame
) >|= or_raise "Uplink listen loop" Netif.pp_error
let interface t = t.interface
let connect config =
let ip = config.Dao.uplink_our_ip in
Netif.connect "0" >>= fun net ->
Eth.connect net >>= fun eth ->
Arp.connect eth >>= fun arp ->
Arp.add_ip arp ip >>= fun () ->
let netvm_mac =
Arp.query arp config.Dao.uplink_netvm_ip
>|= or_raise "Getting MAC of our NetVM" Arp.pp_error in
let interface = new netvm_iface eth netvm_mac
~my_ip:ip
~other_ip:config.Dao.uplink_netvm_ip in
let fragments = Fragments.Cache.create (256 * 1024) in
Lwt.return { net; eth; arp; interface ; fragments }