Add transport_opt() dpr_timeout

To cause a peer connection to be closed following an outgoing DPA, in
case the peer fails to do so. It is the recipient of DPA that should
close the connection according to RFC 6733.

5 files changed, 52 insertions, 11 deletions

diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml
index 27f2d76f28..e22da3c9d5 100644
--- a/lib/diameter/doc/src/diameter.xml
+++ b/lib/diameter/doc/src/diameter.xml
@@ -1163,6 +1163,18 @@ terminated following an outgoing DPR if DPA is not received.</p>
 Defaults to 1000.</p>
 </item>
 
+<marker id="dpr_timeout"/>
+<tag><c>{dpr_timeout, &dict_Unsigned32;}</c></tag>
+<item>
+<p>
+Number of milliseconds after which a transport connection is
+terminated following an incoming DPR if the peer does not close the
+connection.</p>
+
+<p>
+Defaults to 5000.</p>
+</item>
+
 <marker id="length_errors"/>
 <tag><c>{length_errors, exit|handle|discard}</c></tag>
 <item>
diff --git a/lib/diameter/src/base/diameter.erl b/lib/diameter/src/base/diameter.erl
index a45d84f95b..da2695e1be 100644
--- a/lib/diameter/src/base/diameter.erl
+++ b/lib/diameter/src/base/diameter.erl
@@ -343,6 +343,7 @@ call(SvcName, App, Message) ->
     | {capabilities_cb, evaluable()}
     | {capx_timeout, 'Unsigned32'()}
     | {disconnect_cb, evaluable()}
+    | {dpr_timeout, 'Unsigned32'()}
     | {dpa_timeout, 'Unsigned32'()}
     | {length_errors, exit | handle | discard}
     | {connect_timer, 'Unsigned32'()}
diff --git a/lib/diameter/src/base/diameter_config.erl b/lib/diameter/src/base/diameter_config.erl
index aa4d6e5a20..a89831aa5e 100644
--- a/lib/diameter/src/base/diameter_config.erl
+++ b/lib/diameter/src/base/diameter_config.erl
@@ -534,6 +534,7 @@ opt({capabilities, Os}) ->
 
 opt({K, Tmo})
   when K == capx_timeout;
+       K == dpr_timeout;
        K == dpa_timeout ->
     ?IS_UINT32(Tmo);
 
diff --git a/lib/diameter/src/base/diameter_peer_fsm.erl b/lib/diameter/src/base/diameter_peer_fsm.erl
index 8bfdb3ae39..8d67f0aa90 100644
--- a/lib/diameter/src/base/diameter_peer_fsm.erl
+++ b/lib/diameter/src/base/diameter_peer_fsm.erl
@@ -63,7 +63,8 @@
 %% Keys in process dictionary.
 -define(CB_KEY, cb).         %% capabilities callback
 -define(DPR_KEY, dpr).       %% disconnect callback
--define(DPA_KEY, dpa).       %% timeout for DPA reception
+-define(DPA_KEY, dpa).       %% timeout for incoming DPA, or shutdown after
+                             %% outgoing DPA
 -define(REF_KEY, ref).       %% transport_ref()
 -define(Q_KEY, q).           %% transport start queue
 -define(START_KEY, start).   %% start of connected transport
@@ -83,18 +84,26 @@
                      N == ?GOAWAY; N == goaway;
                      N == ?BUSY;   N == busy).
 
-%% RFC 3588:
+%% RFC 6733:
 %%
 %%   Timeout        An application-defined timer has expired while waiting
 %%                  for some event.
 %%
--define(EVENT_TIMEOUT, 10000).
+
 %% Default timeout for reception of CER/CEA.
+-define(CAPX_TIMEOUT, 10000).
 
-%% Default timeout for DPA in response to DPR. A bit short but the
-%% timeout used to be hardcoded. (So it could be worse.)
+%% Default timeout for DPA to be received in response to an outgoing
+%% DPR. A bit short but the timeout used to be hardcoded. (So it could
+%% be worse.)
 -define(DPA_TIMEOUT, 1000).
 
+%% Default timeout for the connection to be closed by the peer
+%% following an outgoing DPA in response to an incoming DPR. It's the
+%% recipient of DPA that should close the connection according to the
+%% RFC.
+-define(DPR_TIMEOUT, 5000).
+
 -type uint32() :: diameter:'Unsigned32'().
 
 -record(state,
@@ -189,9 +198,10 @@ i({Ack, WPid, {M, Ref} = T, Opts, {Mask, Nodes, Dict0, Svc}}) ->
     putr(?REF_KEY, Ref),
     putr(?SEQUENCE_KEY, Mask),
     putr(?RESTRICT_KEY, Nodes),
-    putr(?DPA_KEY, proplists:get_value(dpa_timeout, Opts, ?DPA_TIMEOUT)),
+    putr(?DPA_KEY, {proplists:get_value(dpr_timeout, Opts, ?DPR_TIMEOUT),
+                    proplists:get_value(dpa_timeout, Opts, ?DPA_TIMEOUT)}),
 
-    Tmo = proplists:get_value(capx_timeout, Opts, ?EVENT_TIMEOUT),
+    Tmo = proplists:get_value(capx_timeout, Opts, ?CAPX_TIMEOUT),
     OnLengthErr = proplists:get_value(length_errors, Opts, exit),
 
     {TPid, Addrs} = start_transport(T, Rest, Svc),
@@ -416,7 +426,8 @@ transition({shutdown, Pid, Reason}, #state{parent = Pid, dpr = false} = S) ->
 transition({shutdown, Pid, _}, #state{parent = Pid}) ->
     ok;
 
-%% DPA reception has timed out.
+%% DPA reception has timed out, or peer has not closed the connection
+%% as a result of outgoing DPA.
 transition(dpa_timeout, _) ->
     stop;
 
@@ -840,7 +851,7 @@ cea(CEA, RC, Dict0) ->
 post('CER' = T, RC, Pkt, S) ->
     {T, caps(S), {RC, Pkt}};
 post('DPR', _, _, #state{parent = Pid}) ->
-    [fun(S) -> inform_dpr(Pid), S end].
+    [fun(S) -> dpr_timer(), inform_dpr(Pid), S end].
 
 inform_dpr(Pid) ->
     Pid ! {'DPR', self()}.  %% tell watchdog to die with us
@@ -1247,11 +1258,24 @@ dpa_timer(Tmo) ->
 dpa_timeout() ->
     dpa_timeout(getr(?DPA_KEY)).
 
-dpa_timeout(undefined) ->
+dpa_timeout({_, Tmo}) ->
+    Tmo;
+dpa_timeout(undefined) ->  %% set in old code
     ?DPA_TIMEOUT;
-dpa_timeout(Tmo) ->
+dpa_timeout(Tmo) ->        %% ditto
     Tmo.
 
+dpr_timer() ->
+    dpa_timer(dpr_timeout()).
+
+dpr_timeout() ->
+    dpr_timeout(getr(?DPA_KEY)).
+
+dpr_timeout({Tmo, _}) ->
+    Tmo;
+dpr_timeout(_) ->  %% set in old code
+    ?DPR_TIMEOUT.
+
 %% register_everywhere/1
 %%
 %% Register a term and ensure it's not registered elsewhere. Note that
diff --git a/lib/diameter/test/diameter_config_SUITE.erl b/lib/diameter/test/diameter_config_SUITE.erl
index e61d3aea0e..6779524b14 100644
--- a/lib/diameter/test/diameter_config_SUITE.erl
+++ b/lib/diameter/test/diameter_config_SUITE.erl
@@ -157,6 +157,9 @@
          {length_errors,
           [[exit], [handle], [discard]],
           [[x]]},
+         {dpr_timeout,
+          [[0], [3000], [16#FFFFFFFF]],
+          [[infinity], [-1], [1 bsl 32], [x]]},
          {dpa_timeout,
           [[0], [3000], [16#FFFFFFFF]],
           [[infinity], [-1], [1 bsl 32], [x]]},