(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* Permission is hereby granted, free of charge, to any person obtaining a *)
(* copy of this software and associated documentation files (the "Software"),*)
(* to deal in the Software without restriction, including without limitation *)
(* the rights to use, copy, modify, merge, publish, distribute, sublicense, *)
(* and/or sell copies of the Software, and to permit persons to whom the *)
(* Software is furnished to do so, subject to the following conditions: *)
(* *)
(* The above copyright notice and this permission notice shall be included *)
(* in all copies or substantial portions of the Software. *)
(* *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *)
(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *)
(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *)
(* DEALINGS IN THE SOFTWARE. *)
(* *)
(*****************************************************************************)
module Events = P2p_events.P2p_welcome
type listening_socket_open_failure = {
reason : Unix.error;
address : P2p_addr.t;
port : int;
}
type error += Failed_to_open_listening_socket of listening_socket_open_failure
let () =
register_error_kind
`Permanent
~id:"p2p.welcome.failed_to_open_listening_socket"
~title:"Failed to open listening socket"
~description:"The p2p listening socket could not be opened."
~pp:(fun ppf (reason, address, port) ->
let tips ppf () =
match reason with
| Unix.EADDRINUSE ->
Format.fprintf
ppf
"Another tezos node is probably running on this address.@;\
Please choose another P2P port using --net-addr."
| _ -> Format.fprintf ppf ""
in
Format.fprintf
ppf
"@[<v 2>An error occured while initializing P2P server on this \
address: %a:%d.@;\
Reason: %s.@;\
%a@]"
P2p_addr.pp
address
port
(Unix.error_message reason)
tips
())
Data_encoding.(
obj3
(req "reason" Unix_error.encoding)
(req "address" P2p_addr.encoding)
(req "port" uint16))
(function
| Failed_to_open_listening_socket {reason; address; port} ->
Some (reason, address, port)
| _ -> None)
(fun (reason, address, port) ->
Failed_to_open_listening_socket {reason; address; port})
type connect_handler =
| Connect_handler :
('msg, 'meta, 'meta_conn) P2p_connect_handler.t
-> connect_handler
type t = {
socket : Lwt_unix.file_descr;
canceler : Lwt_canceler.t;
connect_handler : connect_handler;
mutable worker : unit Lwt.t;
}
let rec worker_loop st =
let open Lwt_syntax in
let (Connect_handler connect_handler) = st.connect_handler in
let* () = Lwt.pause () in
let* r =
protect ~canceler:st.canceler (fun () ->
let* r = P2p_fd.accept st.socket in
Result.fold
~ok:(fun (fd, addr) ->
let point =
match addr with
| Lwt_unix.ADDR_UNIX _ -> assert false
| Lwt_unix.ADDR_INET (addr, port) ->
(Ipaddr_unix.V6.of_inet_addr_exn addr, port)
in
P2p_connect_handler.accept connect_handler fd point ;
Lwt.return_ok ())
~error:(function
(* These are temporary system errors, giving some time for
the system to recover *)
| `System_error ex ->
let* () =
Events.(emit incoming_error)
(TzTrace.make (error_of_exn ex), "system")
in
let* () = Lwt_unix.sleep 5. in
Lwt.return_ok ()
(* These errors are specific to attempted incoming connection,
ignoring them. *)
| `Socket_error ex ->
let* () =
Events.(emit incoming_error)
(TzTrace.make (error_of_exn ex), "socket")
in
Lwt.return (Ok ())
| `Unexpected_error ex ->
Lwt.return_error (TzTrace.make (error_of_exn ex)))
r)
in
match r with
| Ok () -> worker_loop st
| Error (Canceled :: _) -> Lwt.return_unit
| Error err -> Events.(emit unexpected_error) err
let create_listening_socket ~backlog ?(addr = Ipaddr.V6.unspecified) port =
let open Lwt_result_syntax in
Lwt.catch
(fun () ->
let main_socket = Lwt_unix.(socket PF_INET6 SOCK_STREAM 0) in
Lwt_unix.(setsockopt main_socket SO_REUSEADDR true) ;
let*! () =
Lwt_unix.bind
main_socket
Unix.(ADDR_INET (Ipaddr_unix.V6.to_inet_addr addr, port))
in
Lwt_unix.listen main_socket backlog ;
return main_socket)
(function
| Unix.Unix_error (err, _, _) ->
tzfail
(Failed_to_open_listening_socket
{reason = err; address = addr; port})
| exn -> Lwt.fail exn)
let create ?addr ~backlog connect_handler port =
let open Lwt_result_syntax in
Lwt.catch
(fun () ->
let* socket = create_listening_socket ~backlog ?addr port in
let canceler = Lwt_canceler.create () in
let st =
{
socket;
canceler;
connect_handler = Connect_handler connect_handler;
worker = Lwt.return_unit;
}
in
Lwt_canceler.on_cancel canceler (fun () ->
let*! () = st.worker in
let*! r = Lwt_utils_unix.safe_close socket in
Result.iter_error_s Events.(emit unexpected_error_closing_socket) r) ;
return st)
(fun exn ->
let error = error_of_exn exn in
let*! () = Events.(emit incoming_connection_error) error in
tzfail error)
let activate st =
st.worker <-
Lwt_utils.worker
"welcome"
~on_event:Internal_event.Lwt_worker_event.on_event
~run:(fun () -> worker_loop st)
~cancel:(fun () -> Error_monad.cancel_with_exceptions st.canceler)
let shutdown st = Error_monad.cancel_with_exceptions st.canceler