mte/unikernel/duniverse/ocaml-tls/lwt/examples/echo_server_alpn.ml
2025-11-11 02:07:51 +01:00

68 lines
2 KiB
OCaml

open Lwt
open Ex_common
let split_on_char sep s =
let r = ref [] in
let j = ref (String.length s) in
for i = String.length s - 1 downto 0 do
if s.[i] = sep then begin
r := String.sub s (i + 1) (!j - i - 1) :: !r;
j := i
end
done;
String.sub s 0 !j :: !r
let serve_ssl alpn_protocols port callback =
let tag = "server" in
X509_lwt.private_of_pems
~cert:server_cert
~priv_key:server_key >>= fun certificate ->
let server_s =
let open Lwt_unix in
let s = socket PF_INET SOCK_STREAM 0 in
bind s (ADDR_INET (Unix.inet_addr_any, port)) >|= fun () ->
listen s 10 ;
s in
let handle ep channels addr =
let alpn = match ep with
| Ok data -> (match data.Tls.Core.alpn_protocol with
| Some a -> a
| None -> "no alpn")
| Error () -> "no session"
in
async @@ fun () ->
Lwt.catch (fun () -> callback alpn channels addr >>= fun () -> yap ~tag "<- handler done")
(function
| Tls_lwt.Tls_alert a ->
yap ~tag @@ "handler: " ^ Tls.Packet.alert_type_to_string a
| exn -> yap ~tag "handler: exception" >>= fun () -> fail exn)
in
let ps = string_of_int port in
yap ~tag ("-> start @ " ^ ps ^ " (use `openssl s_client -connect host:" ^ ps ^ " -alpn <proto>`), available protocols: " ^ String.concat "," alpn_protocols) >>= fun () ->
let rec loop () =
let config = get_ok (Tls.Config.server ~certificates:(`Single certificate) ~alpn_protocols ()) in
server_s >>= fun s ->
Tls_lwt.Unix.accept config s >>= fun (t, addr) ->
yap ~tag "-> connect" >>= fun () ->
( handle (Tls_lwt.Unix.epoch t) (Tls_lwt.of_t t) addr ; loop () )
in
loop ()
let echo_server protocols port =
serve_ssl protocols port @@ fun alpn (ic, oc) _addr ->
lines ic |> Lwt_stream.iter_s (fun line ->
yap ~tag:("handler alpn: " ^ alpn) ("+ " ^ line) >>= fun () ->
Lwt_io.write_line oc line)
let () =
let protocols =
try split_on_char ',' Sys.argv.(1) with _ -> [ "h2" ; "http/1.1" ]
in
Lwt_main.run (echo_server protocols 4433)