ssl: Improve close handling

We want to make sure that the sender process that may get stuck in
prim_inet:send will die if the tls_connection process is
terminated.  And we also like to make sure that it terminates as
gracefully as possible. So when the tls_connection process dies it
spawns a killer process that will brutaly kill the sender if it is
unresponsive and does not terminate due to its monitor of the
tls_connetion process triggering.

When the sender process also acts as distribution controller it
may also have other processess that it is linked with that it
should bring down or that could bring the connection down.

1 files changed, 5 insertions, 42 deletions

diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl
index b17b7fbffe..5769939ee5 100644
--- a/lib/ssl/src/ssl_connection.erl
+++ b/lib/ssl/src/ssl_connection.erl
@@ -64,7 +64,7 @@
 %% General gen_statem state functions with extra callback argument 
 %% to determine if it is an SSL/TLS or DTLS gen_statem machine
 -export([init/4, error/4, hello/4, user_hello/4, abbreviated/4, certify/4, cipher/4,
-         connection/4, death_row/4, death_row/2, downgrade/4]).
+         connection/4, downgrade/4]).
 
 %% gen_statem callbacks
 -export([terminate/3, format_status/2]).
@@ -511,7 +511,7 @@ dist_app_data(ClientData, #state{erl_dist_data = #{dist_handle := DHandle,
         _ -> %% We have more data
             read_application_data(<<>>, State)
     catch error:_ ->
-            death_row(State, disconnect)
+            stop(State, disconnect)
     end.
 
 merge_dist_data(<<>>, ClientData) ->
@@ -1081,29 +1081,6 @@ connection(Type, Msg, State, Connection) ->
     handle_common_event(Type, Msg, ?FUNCTION_NAME, State, Connection).
 
 %%--------------------------------------------------------------------
--spec death_row(gen_statem:event_type(), term(),
-		#state{}, tls_connection | dtls_connection) ->
-		       gen_statem:state_function_result().
-%%--------------------------------------------------------------------
-%% We just wait for the owner to die which triggers the monitor,
-%% or the socket may die too
-death_row(info, {'DOWN', MonitorRef, _, _, Reason},
-          #state{user_application={MonitorRef,_Pid}},_) ->
-    {stop, {shutdown, Reason}};
-death_row(info, {'EXIT', Socket, Reason}, #state{socket = Socket}, _) ->
-    {stop, {shutdown, Reason}};
-death_row(state_timeout, Reason, _State, _Connection) ->
-    {stop, {shutdown,Reason}};
-death_row(_Type, _Msg, _State, _Connection) ->
-    %% Waste all other events
-    keep_state_and_data.
-
-%% State entry function
-death_row(State, Reason) ->
-    {next_state, death_row, State,
-     [{state_timeout, 5000, Reason}]}.
-
-%%--------------------------------------------------------------------
 -spec downgrade(gen_statem:event_type(), term(), 
 		#state{}, tls_connection | dtls_connection) ->
 		       gen_statem:state_function_result().
@@ -2727,26 +2704,12 @@ new_emulated([], EmOpts) ->
     EmOpts;
 new_emulated(NewEmOpts, _) ->
     NewEmOpts.
-%%---------------Erlang distribution --------------------------------------
-%% When acting as distribution controller map the exit reason
-%% to follow the documented nodedown_reason for net_kernel
+
 stop(Reason, State) ->
-    {stop, erl_dist_stop_reason(Reason, State), State}.
+    {stop, Reason, State}.
 
 stop_and_reply(Reason, Replies, State) ->
-    {stop_and_reply, erl_dist_stop_reason(Reason, State), Replies, State}.
-
-erl_dist_stop_reason(
-  Reason, #state{ssl_options = #ssl_options{erl_dist = true}}) ->
-    case Reason of
-        normal ->
-            %% We can not exit with normal since that will not bring
-            %% down the rest of the distribution processes
-            {shutdown, normal};
-        _ -> Reason
-    end;
-erl_dist_stop_reason(Reason, _State) ->
-    Reason.
+    {stop_and_reply, Reason, Replies, State}.
 
 is_dist_up(#{dist_handle := Handle}) when Handle =/= undefined ->
     true;