unikernel/duniverse/mirage-tcpip/test/test_simulatenous_close.ml

@@ -0,0 +1,111 @@
+open Common
+
+open Low_level
+open Lwt.Infix
+
+let close_ack_scenario =
+  let fsm ip state ~src ~dst data =
+    match state with
+    | `WAIT_FOR_SYN ->
+      let syn = Tcp_wire.get_syn data in
+      if syn then (
+        let id = reply_id_from ~src ~dst data in
+        WIRE.xmit ~ip id ~syn:true ~rx_ack:(ack data)
+          ~seq:(Sequence.of_int32 1000000l) ~window
+          ~options (Cstruct.create 0)
+          >|= Result.get_ok >>= fun () ->
+        Lwt.return (Fsm_next `WAIT_FOR_ACK)
+      ) else
+        Lwt.return (Fsm_error "Expected initial syn request")
+    | `WAIT_FOR_ACK ->
+      if Tcp_wire.get_ack data then (
+        let id = reply_id_from ~src ~dst data in
+        WIRE.xmit ~ip id ~rx_ack:(ack data) ~fin:true ~seq:(Sequence.of_int32 1000001l)
+          ~window ~options (Cstruct.create 0)
+        >|= Result.get_ok >>= fun () ->
+        Lwt.return (Fsm_next `WAIT_FOR_FIN)
+      ) else
+        Lwt.return (Fsm_error "Expected final ack of three step dance")
+    | `WAIT_FOR_FIN ->
+      if (Tcp_wire.get_fin data)  then
+        let id = reply_id_from ~src ~dst data in
+        WIRE.xmit ~ip id ~rx_ack:(ack data) ~seq:(Sequence.of_int32 1000002l)
+          ~window:0 ~options (Cstruct.create 0)
+        >|= Result.get_ok >>= fun () ->
+        Lwt.return Fsm_done
+      else
+        Lwt.return (Fsm_error "Fin expected") in
+
+  let sut stack _fail_callback =
+    let conn = VNETIF_STACK.Stack.TCP.create_connection (VNETIF_STACK.Stack.tcp stack) in
+    or_error "connect" conn (Ipaddr.V4 server_ip, 80) >>= fun flow ->
+    (* We should receive the data *)
+    VNETIF_STACK.Stack.TCP.close flow >>= fun () ->
+    Lwt_unix.sleep 4.0 >>= fun () ->
+    Alcotest.(check int) "connection is cleaned" 0 (VNETIF_STACK.T.num_open_channels ((VNETIF_STACK.Stack.tcp stack)));
+    Lwt.return_unit
+  in
+  (`WAIT_FOR_SYN, fsm), sut
+
+  let close_reset_scenario =
+    let fsm ip state ~src ~dst data =
+      match state with
+      | `WAIT_FOR_SYN ->
+        let syn = Tcp_wire.get_syn data in
+        if syn then (
+          let id = reply_id_from ~src ~dst data in
+          WIRE.xmit ~ip id ~syn:true ~rx_ack:(ack data)
+            ~seq:(Sequence.of_int32 1000000l) ~window
+            ~options (Cstruct.create 0)
+            >|= Result.get_ok >>= fun () ->
+          Lwt.return (Fsm_next `WAIT_FOR_ACK)
+        ) else
+          Lwt.return (Fsm_error "Expected initial syn request")
+      | `WAIT_FOR_ACK ->
+        if Tcp_wire.get_ack data then (
+          let id = reply_id_from ~src ~dst data in
+          WIRE.xmit ~ip id ~rx_ack:(ack data) ~fin:true ~seq:(Sequence.of_int32 1000001l)
+            ~window ~options (Cstruct.create 0)
+          >|= Result.get_ok >>= fun () ->
+          Lwt.return (Fsm_next `WAIT_FOR_FIN)
+        ) else
+          Lwt.return (Fsm_error "Expected final ack of three step dance")
+      | `WAIT_FOR_FIN ->
+        if (Tcp_wire.get_fin data)  then
+          let id = reply_id_from ~src ~dst data in
+          WIRE.xmit ~ip id ~rx_ack:None ~rst:true ~seq:(Sequence.of_int32 1000001l)
+            ~window:0 ~options (Cstruct.create 0)
+          >|= Result.get_ok >>= fun () ->
+          Lwt.return (Fsm_next `WAIT_FOR_CHALLENGE_ACK)
+        else
+          Lwt.return (Fsm_error "Expected fin")
+      | `WAIT_FOR_CHALLENGE_ACK ->
+        if (Tcp_wire.get_ack data)  then
+          let id = reply_id_from ~src ~dst data in
+          WIRE.xmit ~ip id ~rx_ack:None ~rst:true ~seq:(Sequence.of_int32 1000002l)
+            ~window:0 ~options (Cstruct.create 0)
+          >|= Result.get_ok >>= fun () ->
+          Lwt.return (Fsm_done)
+        else
+          Lwt.return (Fsm_error "Expected challenge ack")
+    in
+
+    let sut stack _fail_callback =
+      let conn = VNETIF_STACK.Stack.TCP.create_connection (VNETIF_STACK.Stack.tcp stack) in
+      or_error "connect" conn (Ipaddr.V4 server_ip, 80) >>= fun flow ->
+      (* We should receive the data *)
+      VNETIF_STACK.Stack.TCP.close flow >>= fun () ->
+      Lwt_unix.sleep 4.0 >>= fun () ->
+      Alcotest.(check int) "connection is cleaned" 0 (VNETIF_STACK.T.num_open_channels ((VNETIF_STACK.Stack.tcp stack)));
+      Lwt.return_unit
+    in
+    (`WAIT_FOR_SYN, fsm), sut
+
+let run_test pcap_file ((initial_state, fsm), sut) () =
+  let backend = VNETIF_STACK.create_backend () in
+  VNETIF_STACK.record_pcap backend pcap_file  (run backend (initial_state, fsm) sut)
+
+let suite = [
+  "close with ack", `Slow, run_test "close_ack.pcap" close_ack_scenario;
+  "close with reset, challenge ack ok", `Slow, run_test "close_reset.pcap" close_reset_scenario;
+]