Merge branch 'anders/diameter/string_decode/OTP-11952' into maint

* anders/diameter/string_decode/OTP-11952:
  Let examples override default service options
  Set {restrict_connections, false} in example server
  Set {string_decode, false} in examples
  Test {string_decode, false} in traffic suite
  Add service_opt() string_decode
  Strip potentially large terms when sending outgoing Diameter messages
  Improve language consistency in diameter(1)

18 files changed, 526 insertions, 216 deletions

diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml
index 27f2d76f28..d55b761860 100644
--- a/lib/diameter/doc/src/diameter.xml
+++ b/lib/diameter/doc/src/diameter.xml
@@ -303,7 +303,7 @@ Defaults to <c>none</c>.</p>
 <tag><c>{timeout, &dict_Unsigned32;}</c></tag>
 <item>
 <p>
-The number of milliseconds after which the request should
+Number of milliseconds after which the request should
 timeout.
 Defaults to 5000.</p>
 </item>
@@ -742,7 +742,7 @@ info fields of forms other than the above.</p>
 <tag><c>service_name() = term()</c></tag>
 <item>
 <p>
-The name of a service as passed to &start_service; and with which the
+Name of a service as passed to &start_service; and with which the
 service is identified.
 There can be at most one service with a given name on a given node.
 Note that &make_ref;
@@ -754,7 +754,7 @@ can be used to generate a service name that is somewhat unique.</p>
 <tag><c>service_opt()</c></tag>
 <item>
 <p>
-An option passed to &start_service;.
+Option passed to &start_service;.
 Can be any <c>&capability;</c> as well as the following.</p>
 
 <taglist>
@@ -762,7 +762,7 @@ Can be any <c>&capability;</c> as well as the following.</p>
 <tag><c>{application, [&application_opt;]}</c></tag>
 <item>
 <p>
-Defines a Diameter application supported by the service.</p>
+A Diameter application supported by the service.</p>
 
 <p>
 A service must configure one tuple for each Diameter
@@ -790,7 +790,7 @@ be matched by corresponding &capability; configuration, of
                              | evaluable()}</c></tag>
 <item>
 <p>
-Specifies the degree to which the service allows multiple transport
+The degree to which the service allows multiple transport
 connections to the same peer, as identified by its Origin-Host
 at capabilities exchange.</p>
 
@@ -816,7 +816,7 @@ Defaults to <c>nodes</c>.</p>
 <tag><c>{sequence, {H,N} | &evaluable;}</c></tag>
 <item>
 <p>
-Specifies a constant value <c>H</c> for the topmost <c>32-N</c> bits of
+A constant value <c>H</c> for the topmost <c>32-N</c> bits of
 of 32-bit End-to-End and Hop-by-Hop Identifiers generated
 by the service, either explicitly or as a return value of a function
 to be evaluated at &start_service;.
@@ -851,7 +851,7 @@ outgoing requests.</p>
 <tag><c>{share_peers, boolean() | [node()] | evaluable()}</c></tag>
 <item>
 <p>
-Specifies nodes to which peer connections established on the local
+Nodes to which peer connections established on the local
 Erlang node are communicated.
 Shared peers become available in the remote candidates list passed to
 &app_pick_peer; callbacks on remote nodes whose services are
@@ -890,7 +890,7 @@ of a single Diameter node across multiple Erlang nodes.</p>
 <tag><c>{spawn_opt, [term()]}</c></tag>
 <item>
 <p>
-An options list passed to &spawn_opt; when spawning a process for an
+Options list passed to &spawn_opt; when spawning a process for an
 incoming Diameter request, unless the transport in question
 specifies another value.
 Options <c>monitor</c> and <c>link</c> are ignored.</p>
@@ -899,10 +899,34 @@ Options <c>monitor</c> and <c>link</c> are ignored.</p>
 Defaults to the empty list.</p>
 </item>
 
+<marker id="string_decode"/>
+<tag><c>{string_decode, boolean()}</c></tag>
+<item>
+<p>
+Whether or not to decode AVPs of type &dict_OctetString; and its
+derived types &dict_DiameterIdentity;, &dict_DiameterURI;,
+&dict_IPFilterRule;, &dict_QoSFilterRule;, and &dict_UTF8String;.
+If <c>true</c> then AVPs of these types are decoded to string().
+If <c>false</c> then values are retained as binary().</p>
+
+<p>
+Defaults to <c>true</c>.</p>
+
+<warning>
+<p>
+This option should be set to <c>false</c>
+since a sufficiently malicious peer can otherwise cause large amounts
+of memory to be consumed when decoded Diameter messages are passed
+between processes.
+The default value is for backwards compatibility.</p>
+</warning>
+
+</item>
+
 <tag><c>{use_shared_peers, boolean() | [node()] | evaluable()}</c></tag>
 <item>
 <p>
-Specifies nodes from which communicated peers are made available in
+Nodes from which communicated peers are made available in
 the remote candidates list of &app_pick_peer; callbacks.</p>
 
 <p>
@@ -942,7 +966,7 @@ each node from which requests are sent.</p>
 <tag><c>transport_opt()</c></tag>
 <item>
 <p>
-An option passed to &add_transport;.
+Option passed to &add_transport;.
 Has one of the following types.</p>
 
 <taglist>
@@ -950,8 +974,7 @@ Has one of the following types.</p>
 <tag><c>{applications, [&application_alias;]}</c></tag>
 <item>
 <p>
-The list of Diameter applications to which the transport should be
-restricted.
+Diameter applications to which the transport should be restricted.
 Defaults to all applications configured on the service in question.
 Applications not configured on the service in question are ignored.</p>
 
@@ -984,7 +1007,7 @@ TLS is desired over TCP as implemented by &man_tcp;.</p>
 <tag><c>{capabilities_cb, &evaluable;}</c></tag>
 <item>
 <p>
-A callback invoked upon reception of CER/CEA during capabilities
+Callback invoked upon reception of CER/CEA during capabilities
 exchange in order to ask whether or not the connection should
 be accepted.
 Applied to the <c>&transport_ref;</c> and
@@ -1218,7 +1241,7 @@ the same peer.</p>
 <tag><c>{spawn_opt, [term()]}</c></tag>
 <item>
 <p>
-Options list passed to &spawn_opt; when spawning a process for an
+Options passed to &spawn_opt; when spawning a process for an
 incoming Diameter request.
 Options <c>monitor</c> and <c>link</c> are ignored.</p>
 
diff --git a/lib/diameter/doc/src/diameter_dict.xml b/lib/diameter/doc/src/diameter_dict.xml
index 810a146b88..9db9bcffde 100644
--- a/lib/diameter/doc/src/diameter_dict.xml
+++ b/lib/diameter/doc/src/diameter_dict.xml
@@ -529,6 +529,11 @@ answer record and passed to a &app_handle_request;
 callback upon reception of an incoming request.</p>
 
 <p>
+In cases in which there is a choice between list() and binary() types
+for OctetString() and derived types, the representation is determined
+by the value of &mod_string_decode;.</p>
+
+<p>
 <em>Basic AVP Data Formats</em></p>
 
 <marker id="OctetString"/>
@@ -541,7 +546,7 @@ callback upon reception of an incoming request.</p>
 <marker id="Grouped"/>
 
 <pre>
-OctetString() = [0..255]
+OctetString() = string() | binary()
 Integer32()   = -2147483647..2147483647
 Integer64()   = -9223372036854775807..9223372036854775807
 Unsigned32()  = 0..4294967295
@@ -603,7 +608,7 @@ and <c>{{2104,2,26},{9,42,23}}</c> (both inclusive) can be encoded.</p>
 
 <marker id="UTF8String"/>
 <pre>
-UTF8String() = [integer()]
+UTF8String() = [integer()] | binary()
 </pre>
 
 <p>
diff --git a/lib/diameter/doc/src/seealso.ent b/lib/diameter/doc/src/seealso.ent
index 8d87a4a5e7..4e205ffad7 100644
--- a/lib/diameter/doc/src/seealso.ent
+++ b/lib/diameter/doc/src/seealso.ent
@@ -70,6 +70,8 @@ significant.
 <!ENTITY connect_timer '<seealso marker="#connect_timer">connect_timer</seealso>'>
 <!ENTITY watchdog_timer '<seealso marker="#watchdog_timer">watchdog_timer</seealso>'>
 
+<!ENTITY mod_string_decode '<seealso marker="diameter#service_opt">diameter:service_opt()</seealso> <seealso marker="diameter#string_decode">string_decode</seealso>'>
+
 <!-- diameter_app -->
 
 <!ENTITY app_handle_answer '<seealso marker="diameter_app#Mod:handle_answer-4">handle_answer/4</seealso>'>
@@ -103,6 +105,9 @@ significant.
 
 <!ENTITY dict_Address '<seealso marker="diameter_dict#DATA_TYPES">Address()</seealso>'>
 <!ENTITY dict_DiameterIdentity '<seealso marker="diameter_dict#DATA_TYPES">DiameterIdentity()</seealso>'>
+<!ENTITY dict_DiameterURI '<seealso marker="diameter_dict#DATA_TYPES">DiameterURI()</seealso>'>
+<!ENTITY dict_IPFilterRule '<seealso marker="diameter_dict#DATA_TYPES">IPFilterRule()</seealso>'>
+<!ENTITY dict_QoSFilterRule '<seealso marker="diameter_dict#DATA_TYPES">QoSFilterRule()</seealso>'>
 <!ENTITY dict_Grouped '<seealso marker="diameter_dict#DATA_TYPES">Grouped()</seealso>'>
 <!ENTITY dict_OctetString '<seealso marker="diameter_dict#DATA_TYPES">OctetString()</seealso>'>
 <!ENTITY dict_Time '<seealso marker="diameter_dict#DATA_TYPES">Time()</seealso>'>
diff --git a/lib/diameter/examples/code/client.erl b/lib/diameter/examples/code/client.erl
index be5b4cbba5..844c9cdbdd 100644
--- a/lib/diameter/examples/code/client.erl
+++ b/lib/diameter/examples/code/client.erl
@@ -41,6 +41,7 @@
 -include_lib("diameter/include/diameter_gen_base_rfc6733.hrl").
 
 -export([start/1,     %% start a service
+         start/2,     %%
          connect/2,   %% add a connecting transport
          call/1,      %% send using the record encoding
          cast/1,      %% send using the list encoding and detached
@@ -68,6 +69,7 @@
                         {'Vendor-Id', 0},
                         {'Product-Name', "Client"},
                         {'Auth-Application-Id', [0]},
+                        {string_decode, false},
                         {application, [{alias, common},
                                        {dictionary, diameter_gen_base_rfc6733},
                                        {module, client_cb}]}]).
@@ -76,11 +78,23 @@
 
 start(Name)
   when is_atom(Name) ->
-    node:start(Name, ?SERVICE(Name)).
+    start(Name, []);
+
+start(Opts)
+  when is_list(Opts) ->
+    start(?DEF_SVC_NAME, Opts).
+
+%% start/0
 
 start() ->
     start(?DEF_SVC_NAME).
 
+%% start/2
+
+start(Name, Opts) ->
+    node:start(Name, Opts ++ [T || {K,_} = T <- ?SERVICE(Name),
+                                   false == lists:keymember(K, 1, Opts)]).
+
 %% connect/2
 
 connect(Name, T) ->
diff --git a/lib/diameter/examples/code/relay.erl b/lib/diameter/examples/code/relay.erl
index 0aa3cd06d3..7bc46dc68d 100644
--- a/lib/diameter/examples/code/relay.erl
+++ b/lib/diameter/examples/code/relay.erl
@@ -32,6 +32,7 @@
 -module(relay).
 
 -export([start/1,
+         start/2,
          listen/2,
          connect/2,
          stop/1]).
@@ -49,6 +50,7 @@
                         {'Vendor-Id', 193},
                         {'Product-Name', "RelayAgent"},
                         {'Auth-Application-Id', [16#FFFFFFFF]},
+                        {string_decode, false},
                         {application, [{alias, relay},
                                        {dictionary, diameter_relay},
                                        {module, relay_cb}]}]).
@@ -57,11 +59,19 @@
 
 start(Name)
   when is_atom(Name) ->
-    node:start(Name, ?SERVICE(Name)).
+    start(Name, []).
+
+%% start/1
 
 start() ->
     start(?DEF_SVC_NAME).
 
+%% start/2
+
+start(Name, Opts) ->
+    node:start(Name, Opts ++ [T || {K,_} = T <- ?SERVICE(Name),
+                                   false == lists:keymember(K, 1, Opts)]).
+
 %% listen/2
 
 listen(Name, T) ->
diff --git a/lib/diameter/examples/code/server.erl b/lib/diameter/examples/code/server.erl
index 8c91e68895..f32cec594c 100644
--- a/lib/diameter/examples/code/server.erl
+++ b/lib/diameter/examples/code/server.erl
@@ -35,6 +35,7 @@
 -module(server).
 
 -export([start/1,    %% start a service
+         start/2,    %%
          listen/2,   %% add a listening transport
          stop/1]).   %% stop a service
 
@@ -53,6 +54,8 @@
                         {'Vendor-Id', 193},
                         {'Product-Name', "Server"},
                         {'Auth-Application-Id', [0]},
+                        {restrict_connections, false},
+                        {string_decode, false},
                         {application, [{alias, common},
                                        {dictionary, diameter_gen_base_rfc6733},
                                        {module, server_cb}]}]).
@@ -61,11 +64,23 @@
 
 start(Name)
   when is_atom(Name) ->
-    node:start(Name, ?SERVICE(Name)).
+    start(Name, []);
+
+start(Opts)
+  when is_list(Opts) ->
+    start(?DEF_SVC_NAME, Opts).
+
+%% start/0
 
 start() ->
     start(?DEF_SVC_NAME).
 
+%% start/2
+
+start(Name, Opts) ->
+    node:start(Name, Opts ++ [T || {K,_} = T <- ?SERVICE(Name),
+                                   false == lists:keymember(K, 1, Opts)]).
+
 %% listen/2
 
 listen(Name, T) ->
diff --git a/lib/diameter/src/base/diameter.erl b/lib/diameter/src/base/diameter.erl
index a45d84f95b..8e3e9c7e23 100644
--- a/lib/diameter/src/base/diameter.erl
+++ b/lib/diameter/src/base/diameter.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2014. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -306,6 +306,7 @@ call(SvcName, App, Message) ->
     | {restrict_connections, restriction()}
     | {sequence, sequence() | evaluable()}
     | {share_peers, remotes()}
+    | {string_decode, boolean()}
     | {use_shared_peers, remotes()}
     | {spawn_opt, list()}.
 
diff --git a/lib/diameter/src/base/diameter_capx.erl b/lib/diameter/src/base/diameter_capx.erl
index 93548ecafd..7dc61f229f 100644
--- a/lib/diameter/src/base/diameter_capx.erl
+++ b/lib/diameter/src/base/diameter_capx.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2013. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -50,7 +50,8 @@
 -export([build_CER/2,
          recv_CER/3,
          recv_CEA/3,
-         make_caps/2]).
+         make_caps/2,
+         binary_caps/1]).
 
 -include_lib("diameter/include/diameter.hrl").
 -include("diameter_internal.hrl").
@@ -115,7 +116,8 @@ mk_caps(Caps0, Opts) ->
 
 -define(SC(K,F),
         set_cap({K, Val}, {Caps, #diameter_caps{F = false} = C}) ->
-            {Caps#diameter_caps{F = cap(K, Val)}, C#diameter_caps{F = true}}).
+            {Caps#diameter_caps{F = cap(K, copy(Val))},
+             C#diameter_caps{F = true}}).
 
 ?SC('Origin-Host',         origin_host);
 ?SC('Origin-Realm',        origin_realm);
@@ -375,10 +377,10 @@ capx_to_caps(CEX, Dict) ->
                         'Firmware-Revision',
                         'AVP'],
                        CEX),
-    #diameter_caps{origin_host = OH,
-                   origin_realm = OR,
+    #diameter_caps{origin_host = copy(OH),
+                   origin_realm = copy(OR),
                    vendor_id = VId,
-                   product_name = PN,
+                   product_name = copy(PN),
                    origin_state_id = OSI,
                    host_ip_address = IP,
                    supported_vendor_id = SV,
@@ -389,6 +391,32 @@ capx_to_caps(CEX, Dict) ->
                    firmware_revision = FR,
                    avp = X}.
 
+%% Copy binaries to avoid retaining a reference to a large binary
+%% containing AVPs we aren't interested in.
+copy(B)
+  when is_binary(B) ->
+    binary:copy(B);
+
+copy(T) ->
+    T.
+
+%% binary_caps/1
+%%
+%% Encode stringish capabilities with {string_decode, false}.
+
+binary_caps(Caps) ->
+    lists:foldl(fun bcaps/2, Caps, [#diameter_caps.origin_host,
+                                    #diameter_caps.origin_realm,
+                                    #diameter_caps.product_name]).
+
+bcaps(N, Caps) ->
+    case element(N, Caps) of
+        undefined ->
+            Caps;
+        V ->
+            setelement(N, Caps, iolist_to_binary(V))
+    end.
+
 %% ---------------------------------------------------------------------------
 %% ---------------------------------------------------------------------------
 
diff --git a/lib/diameter/src/base/diameter_codec.erl b/lib/diameter/src/base/diameter_codec.erl
index 3a0a030fc9..cc0953f5d3 100644
--- a/lib/diameter/src/base/diameter_codec.erl
+++ b/lib/diameter/src/base/diameter_codec.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2014. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -22,6 +22,8 @@
 -export([encode/2,
          decode/2,
          decode/3,
+         setopts/1,
+         getopt/1,
          collect_avps/1,
          decode_header/1,
          sequence_numbers/1,
@@ -59,6 +61,41 @@
 %%    +-+-+-+-+-+-+-+-+-+-+-+-+-
 
 %%% ---------------------------------------------------------------------------
+%%% # setopts/1
+%%% # getopt/1
+%%% ---------------------------------------------------------------------------
+
+%% These functions are a compromise in the same vein as the use of the
+%% process dictionary in diameter_gen.hrl in generated codec modules.
+%% Instead of rewriting the entire dictionary generation to pass
+%% encode/decode options around, the calling process sets them by
+%% calling setopts/1. At current, the only option is whether or not to
+%% decode binaries as strings, which is used by diameter_types.
+
+setopts(Opts)
+  when is_list(Opts) ->
+    lists:foreach(fun setopt/1, Opts).
+
+%% Decode stringish types to string()? The default true is for
+%% backwards compatibility.
+setopt({string_decode = K, false = B}) ->
+    setopt(K, B);
+
+setopt(_) ->
+    ok.
+
+setopt(Key, Value) ->
+    put({diameter, Key}, Value).
+
+getopt(Key) ->
+    case get({diameter, Key}) of
+        undefined when Key == string_decode ->
+            true;
+        V ->
+            V
+    end.
+
+%%% ---------------------------------------------------------------------------
 %%% # encode/2
 %%% ---------------------------------------------------------------------------
 
diff --git a/lib/diameter/src/base/diameter_config.erl b/lib/diameter/src/base/diameter_config.erl
index aa4d6e5a20..05e9ab88fd 100644
--- a/lib/diameter/src/base/diameter_config.erl
+++ b/lib/diameter/src/base/diameter_config.erl
@@ -644,13 +644,23 @@ make_config(SvcName, Opts) ->
                          {false, monitor},
                          {?NOMASK, sequence},
                          {nodes, restrict_connections},
+                         {true, string_decode},
                          {[], spawn_opt}]),
 
+    D = proplists:get_value(string_decode, SvcOpts, true),
+
     #service{name = SvcName,
              rec = #diameter_service{applications = Apps,
-                                     capabilities = Caps},
+                                     capabilities = binary_caps(Caps, D)},
              options = SvcOpts}.
 
+binary_caps(Caps, true) ->
+    Caps;
+binary_caps(Caps, false) ->
+    diameter_capx:binary_caps(Caps).
+
+%% make_opts/2
+
 make_opts(Opts, Defs) ->
     Known = [{K, get_opt(K, Opts, D)} || {D,K} <- Defs],
     Unknown = Opts -- Known,
@@ -669,7 +679,8 @@ opt(K, false = B)
 
 opt(K, true = B)
   when K == share_peers;
-       K == use_shared_peers ->
+       K == use_shared_peers;
+       K == string_decode ->
     B;
 
 opt(restrict_connections, T)
diff --git a/lib/diameter/src/base/diameter_peer.erl b/lib/diameter/src/base/diameter_peer.erl
index ea326dd03e..89b63c8a92 100644
--- a/lib/diameter/src/base/diameter_peer.erl
+++ b/lib/diameter/src/base/diameter_peer.erl
@@ -232,12 +232,22 @@ recv(Pid, Pkt) ->
 %% # send/2
 %% ---------------------------------------------------------------------------
 
-send(Pid, #diameter_packet{transport_data = undefined,
-			   bin = Bin}) ->
-    send(Pid, Bin);
+send(Pid, Msg) ->
+    ifc_send(Pid, {send, strip(Msg)}).
 
-send(Pid, Pkt) ->
-    ifc_send(Pid, {send, Pkt}).
+%% Send only binary when possible.
+strip(#diameter_packet{transport_data = undefined,
+                       bin = Bin}) ->
+    Bin;
+
+%% Strip potentially large message terms.
+strip(#diameter_packet{transport_data = T,
+                       bin = Bin}) ->
+    #diameter_packet{transport_data = T,
+                     bin = Bin};
+
+strip(Msg) ->
+    Msg.
 
 %% ---------------------------------------------------------------------------
 %% # close/1
@@ -326,7 +336,6 @@ code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
 %% ---------------------------------------------------------
-%% INTERNAL FUNCTIONS
 %% ---------------------------------------------------------
 
 %% ifc_send/2
diff --git a/lib/diameter/src/base/diameter_peer_fsm.erl b/lib/diameter/src/base/diameter_peer_fsm.erl
index 9ff6845ab7..af0fce57a8 100644
--- a/lib/diameter/src/base/diameter_peer_fsm.erl
+++ b/lib/diameter/src/base/diameter_peer_fsm.erl
@@ -140,7 +140,8 @@
 %% # start/3
 %% ---------------------------------------------------------------------------
 
--spec start(T, [Opt], {diameter:sequence(),
+-spec start(T, [Opt], {[diameter:service_opt()]
+                       | diameter:sequence(),  %% from old code
                        [node()],
                        module(),
                        #diameter_service{}})
@@ -179,10 +180,15 @@ init(T) ->
     proc_lib:init_ack({ok, self()}),
     gen_server:enter_loop(?MODULE, [], i(T)).
 
-i({Ack, WPid, {M, Ref} = T, Opts, {Mask, Nodes, Dict0, Svc}}) ->
+i({Ack, WPid, T, Opts, {{_,_} = Mask, Nodes, Dict0, Svc}}) -> %% from old code
+    i({Ack, WPid, T, Opts, {[{sequence, Mask}], Nodes, Dict0, Svc}});
+
+i({Ack, WPid, {M, Ref} = T, Opts, {SvcOpts, Nodes, Dict0, Svc}}) ->
     erlang:monitor(process, WPid),
     wait(Ack, WPid),
     diameter_stats:reg(Ref),
+    diameter_codec:setopts(SvcOpts),
+    {_,_} = Mask = proplists:get_value(sequence, SvcOpts),
     {[Cs,Ds], Rest} = proplists:split(Opts, [capabilities_cb, disconnect_cb]),
     putr(?CB_KEY, {Ref, [F || {_,F} <- Cs]}),
     putr(?DPR_KEY, [F || {_, F} <- Ds]),
@@ -788,6 +794,8 @@ build_answer('CER',
              = Pkt,
              #state{dictionary = Dict0}
              = S) ->
+    diameter_codec:setopts([{string_decode, false}]),
+
     {SupportedApps, RCaps, CEA} = recv_CER(CER, S),
 
     [RC, IS] = Dict0:'#get-'(['Result-Code', 'Inband-Security-Id'], CEA),
@@ -978,6 +986,8 @@ handle_CEA(#diameter_packet{header = H}
         = DPkt
         = diameter_codec:decode(Dict0, Pkt),
 
+    diameter_codec:setopts([{string_decode, false}]),
+
     RC = result_code(incr_rc(recv, DPkt, Dict0)),
 
     {SApps, IS, RCaps} = recv_CEA(DPkt, S),
diff --git a/lib/diameter/src/base/diameter_service.erl b/lib/diameter/src/base/diameter_service.erl
index 04401a3d87..a01bcdd4e7 100644
--- a/lib/diameter/src/base/diameter_service.erl
+++ b/lib/diameter/src/base/diameter_service.erl
@@ -130,7 +130,8 @@
          :: [{sequence, diameter:sequence()}  %% sequence mask
              | {share_peers, diameter:remotes()}       %% broadcast to
              | {use_shared_peers, diameter:remotes()}  %% use from
-             | {restrict_connections, diameter:restriction()}]}).
+             | {restrict_connections, diameter:restriction()}
+             | {string_decode, boolean()}]}).
 %% shared_peers reflects the peers broadcast from remote nodes.
 
 %% Record representing an RFC 3539 watchdog process implemented by
@@ -261,16 +262,22 @@ whois(SvcName) ->
 %% ---------------------------------------------------------------------------
 
 -spec pick_peer(SvcName, AppOrAlias, Opts)
-   -> {{TPid, Caps, App}, Mask}
-    | false
-    | {error, term()}
+   -> {{TPid, Caps, App}, Mask, SvcOpts}
+    | false  %% no selection
+    | {error, no_service}
  when SvcName :: diameter:service_name(),
-      AppOrAlias :: {alias, diameter:app_alias()} | #diameter_app{},
-      Opts :: tuple(),
+      AppOrAlias :: #diameter_app{}
+                  | {alias, diameter:app_alias()},
+      Opts :: {fun((Dict :: module()) -> [term()]),
+               diameter:peer_filter(),
+               Xtra :: list()},
       TPid :: pid(),
       Caps :: #diameter_caps{},
       App  :: #diameter_app{},
-      Mask :: diameter:sequence().
+      Mask :: diameter:sequence(),
+      SvcOpts :: [diameter:service_opt()].
+%% Extract Mask in the returned tuple so that diameter_traffic doesn't
+%% need to know about the ordering of SvcOpts used here.
 
 pick_peer(SvcName, App, Opts) ->
     pick(lookup_state(SvcName), App, Opts).
@@ -287,10 +294,10 @@ pick(#state{service = #diameter_service{applications = Apps}}
      Opts) ->  %% initial call from diameter:call/4
     pick(S, find_outgoing_app(Alias, Apps), Opts);
 
-pick(_, false, _) ->
-    false;
+pick(_, false = No, _) ->
+    No;
 
-pick(#state{options = [{_, Mask} | _]}
+pick(#state{options = [{_, Mask} | SvcOpts]}
      = S,
      #diameter_app{module = ModX, dictionary = Dict}
      = App0,
@@ -299,7 +306,7 @@ pick(#state{options = [{_, Mask} | _]}
     [_,_] = RealmAndHost = diameter_lib:eval([DestF, Dict]),
     case pick_peer(App, RealmAndHost, Filter, S) of
         {TPid, Caps} ->
-            {{TPid, Caps, App}, Mask};
+            {{TPid, Caps, App}, Mask, SvcOpts};
         false = No ->
             No
     end.
@@ -690,7 +697,8 @@ service_options(Opts) ->
      {restrict_connections, proplists:get_value(restrict_connections,
                                                 Opts,
                                                 ?RESTRICT)},
-     {spawn_opt, proplists:get_value(spawn_opt, Opts, [])}].
+     {spawn_opt, proplists:get_value(spawn_opt, Opts, [])},
+     {string_decode, proplists:get_value(string_decode, Opts, true)}].
 %% The order of options is significant since we match against the list.
 
 mref(false = No) ->
@@ -802,10 +810,13 @@ start(Ref, Type, Opts, N, #state{watchdogT = WatchdogT,
   when Type == connect;
        Type == accept ->
     #diameter_service{applications = Apps}
-        = Svc
+        = Svc1
         = merge_service(Opts, Svc0),
-    {_,_} = Mask = proplists:get_value(sequence, SvcOpts),
-    RecvData = diameter_traffic:make_recvdata([SvcName, PeerT, Apps, Mask]),
+    Svc = binary_caps(Svc1, proplists:get_value(string_decode, SvcOpts, true)),
+    RecvData = diameter_traffic:make_recvdata([SvcName,
+                                               PeerT,
+                                               Apps,
+                                               SvcOpts]),
     T = {{spawn_opts([Opts, SvcOpts]), RecvData}, Opts, SvcOpts, Svc},
     Rec = #watchdog{type = Type,
                     ref = Ref,
@@ -816,8 +827,13 @@ start(Ref, Type, Opts, N, #state{watchdogT = WatchdogT,
                         [],
                         N).
 
+binary_caps(Svc, true) ->
+    Svc;
+binary_caps(#diameter_service{capabilities = Caps} = Svc, false) ->
+    Svc#diameter_service{capabilities = diameter_capx:binary_caps(Caps)}.
+
 wd(Type, Ref, T, WatchdogT, Rec) ->
-    Pid = wd(Type, Ref, T),
+    Pid = start_watchdog(Type, Ref, T),
     insert(WatchdogT, Rec#watchdog{pid = Pid}),
     Pid.
 
@@ -831,7 +847,7 @@ spawn_opts(Optss) ->
           T /= link,
           T /= monitor].
 
-wd(Type, Ref, T) ->
+start_watchdog(Type, Ref, T) ->
     {_MRef, Pid} = diameter_watchdog:start({Type, Ref}, T),
     Pid.
 
@@ -852,7 +868,7 @@ ms({applications, As}, #diameter_service{applications = Apps} = S)
 
 %% The fact that all capabilities can be configured on the transports
 %% means that the service doesn't necessarily represent a single
-%% locally implemented Diameter peer as identified by Origin-Host: a
+%% locally implemented Diameter node as identified by Origin-Host: a
 %% transport can configure its own Origin-Host. This means that the
 %% service little more than a placeholder for default capabilities
 %% plus a list of applications that individual transports can choose
diff --git a/lib/diameter/src/base/diameter_traffic.erl b/lib/diameter/src/base/diameter_traffic.erl
index 0c62ccea49..c1c5a35531 100644
--- a/lib/diameter/src/base/diameter_traffic.erl
+++ b/lib/diameter/src/base/diameter_traffic.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2013-2014. All Rights Reserved.
+%% Copyright Ericsson AB 2013-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -77,7 +77,8 @@
         {peerT        :: ets:tid(),
          service_name :: diameter:service_name(),
          apps         :: [#diameter_app{}],
-         sequence     :: diameter:sequence()}).
+         sequence     :: diameter:sequence(),
+         codec        :: list()}).
 
 %% Record stored in diameter_request for each outgoing request.
 -record(request,
@@ -92,11 +93,16 @@
 %% # make_recvdata/1
 %% ---------------------------------------------------------------------------
 
-make_recvdata([SvcName, PeerT, Apps, Mask | _]) ->
+make_recvdata([SvcName, PeerT, Apps, {_,_} = Mask | _]) ->  %% from old code
+    make_recvdata([SvcName, PeerT, Apps, [{sequence, Mask}]]);
+
+make_recvdata([SvcName, PeerT, Apps, SvcOpts | _]) ->
+    {_,_} = Mask = proplists:get_value(sequence, SvcOpts),
     #recvdata{service_name = SvcName,
               peerT = PeerT,
               apps = Apps,
-              sequence = Mask}.
+              sequence = Mask,
+              codec = [T || {K,_} = T <- SvcOpts, K == string_decode]}.
 
 %% ---------------------------------------------------------------------------
 %% peer_up/1
@@ -270,8 +276,11 @@ recv_request(TPid,
              #diameter_packet{header = #diameter_header{application_id = Id}}
              = Pkt,
              Dict0,
-             #recvdata{peerT = PeerT, apps = Apps}
+             #recvdata{peerT = PeerT,
+                       apps = Apps,
+                       codec = Opts}
              = RecvData) ->
+    diameter_codec:setopts(Opts),
     send_A(recv_R(diameter_service:find_incoming_app(PeerT, TPid, Id, Apps),
                   TPid,
                   Pkt,
@@ -279,7 +288,13 @@ recv_request(TPid,
                   RecvData),
            TPid,
            Dict0,
-           RecvData).
+           RecvData);
+
+recv_request(TPid, Pkt, Dict0, RecvData) -> %% from old code
+    recv_request(TPid,
+                 Pkt,
+                 Dict0,
+                 #recvdata{} = erlang:append_element(RecvData, [])).
 
 %% recv_R/5
 
@@ -1225,10 +1240,9 @@ answer_rc(_, _, Sent) ->
 
 send_R(SvcName, AppOrAlias, Msg, Opts, Caller) ->
     case pick_peer(SvcName, AppOrAlias, Msg, Opts) of
-        {{_,_,_} = Transport, Mask} ->
+        {Transport, Mask, SvcOpts} ->
+            diameter_codec:setopts(SvcOpts),
             send_request(Transport, Mask, Msg, Opts, Caller, SvcName);
-        false ->
-            {error, no_connection};
         {error, _} = No ->
             No
     end.
@@ -1290,6 +1304,8 @@ send_request({TPid, Caps, App}
            SvcName,
            []).
 
+%% send_R/7
+
 send_R({send, Msg}, Pkt, Transport, Opts, Caller, SvcName, Fs) ->
     send_R(make_request_packet(Msg, Pkt),
            Transport,
@@ -1550,7 +1566,9 @@ a(Hdr, SvcName, discard) ->
 %% timer value is ignored. This means that an answer could be accepted
 %% from a peer after timeout in the case of failover.
 
-retransmit({{_,_,App} = Transport, _Mask}, Req, Opts, SvcName, Timeout) ->
+%% retransmit/5
+
+retransmit({{_,_,App} = Transport, _, _}, Req, Opts, SvcName, Timeout) ->
     try retransmit(Transport, Req, SvcName, Timeout) of
         T -> recv_A(Timeout, SvcName, App, Opts, T)
     catch
@@ -1571,17 +1589,26 @@ pick_peer(SvcName,
     pick_peer(SvcName, App, Msg, Opts#options{extra = []});
 
 pick_peer(_, _, undefined, _) ->
-    false;
+    {error, no_connection};
 
 pick_peer(SvcName,
           AppOrAlias,
           Msg,
           #options{filter = Filter, extra = Xtra}) ->
-    diameter_service:pick_peer(SvcName,
-                               AppOrAlias,
-                               {fun(D) -> get_destination(D, Msg) end,
-                                Filter,
-                                Xtra}).
+    pick(diameter_service:pick_peer(SvcName,
+                                    AppOrAlias,
+                                    {fun(D) -> get_destination(D, Msg) end,
+                                     Filter,
+                                     Xtra})).
+
+pick({{_,_,_} = Transport, Mask}) ->  %% from old code; dialyzer complains
+    {Transport, Mask, []};            %% about this
+
+pick(false) ->
+    {error, no_connection};
+
+pick(T) ->
+    T.
 
 %% handle_error/4
 
@@ -1679,8 +1706,14 @@ recv(TPid, Pid, TRef, Ref) ->
 
 %% send/2
 
-send(Pid, Pkt) ->
-    Pid ! {send, Pkt}.
+send(Pid, Pkt) ->  %% Strip potentially large message terms.
+    #diameter_packet{header = H,
+                     bin = Bin,
+                     transport_data = T}
+        = Pkt,
+    Pid ! {send, #diameter_packet{header = H,
+                                  bin = Bin,
+                                  transport_data = T}}.
 
 %% retransmit/4
 
diff --git a/lib/diameter/src/base/diameter_types.erl b/lib/diameter/src/base/diameter_types.erl
index 442d90c98b..28a0635c57 100644
--- a/lib/diameter/src/base/diameter_types.erl
+++ b/lib/diameter/src/base/diameter_types.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2013. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2015. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -90,7 +90,12 @@
 
 'OctetString'(decode, Bin)
   when is_binary(Bin) ->
-    binary_to_list(Bin);
+    case diameter_codec:getopt(string_decode) of
+        true ->
+            binary_to_list(Bin);
+        _ ->
+            Bin
+    end;
 
 'OctetString'(decode, B) ->
     ?INVALID_LENGTH(B);
@@ -298,17 +303,19 @@
     'OctetString'(M, lists:duplicate(0,7));
 
 'DiameterURI'(encode, #diameter_uri{type = Type,
-                                    fqdn = D,
-                                    port = P,
+                                    fqdn = DN,
+                                    port = PN,
                                     transport = T,
-                                    protocol = Prot}
-                      = U) ->
-    S = lists:append([atom_to_list(Type), "://", D,
-                      ":", integer_to_list(P),
+                                    protocol = P})
+  when (Type == 'aaa' orelse Type == 'aaas'),
+       is_integer(PN),
+       0 =< PN,
+       (T == tcp orelse T == sctp orelse T == udp),
+       (P == diameter orelse P == radius orelse P == 'tacacs+') ->
+    iolist_to_binary([atom_to_list(Type), "://", DN,
+                      ":", integer_to_list(PN),
                       ";transport=", atom_to_list(T),
-                      ";protocol=", atom_to_list(Prot)]),
-    U = scan_uri(S), %% assert
-    list_to_binary(S);
+                      ";protocol=", atom_to_list(P)]);
 
 'DiameterURI'(encode, Str) ->
     Bin = iolist_to_binary(Str),
@@ -321,7 +328,6 @@
 'IPFilterRule'(encode = M, zero) ->
     'OctetString'(M, lists:duplicate(0,33));
 
-%% TODO: parse grammar.
 'IPFilterRule'(M, X) ->
     'OctetString'(M, X).
 
@@ -331,7 +337,6 @@
 'QoSFilterRule'(encode = M, zero = X) ->
     'IPFilterRule'(M, X);
 
-%% TODO: parse grammar.
 'QoSFilterRule'(M, X) ->
     'OctetString'(M, X).
 
@@ -339,7 +344,13 @@
 
 'UTF8String'(decode, Bin)
   when is_binary(Bin) ->
-    tl([0|_] = unicode:characters_to_list([0, Bin])); %% assert list return
+    case diameter_codec:getopt(string_decode) of
+        true ->
+            %% assert list return
+            tl([0|_] = unicode:characters_to_list([0, Bin]));
+        false ->
+            <<_/binary>> = unicode:characters_to_binary(Bin)
+    end;
 
 'UTF8String'(decode, B) ->
     ?INVALID_LENGTH(B);
@@ -507,55 +518,42 @@ msb(false) -> ?TIME_2036.
 %%
 %%       aaa-protocol       = ( "diameter" / "radius" / "tacacs+" )
 
-scan_uri(Bin)
-  when is_binary(Bin) ->
-    scan_uri(binary_to_list(Bin));
-scan_uri("aaa://" ++ Rest) ->
-    scan_fqdn(Rest, #diameter_uri{type = aaa});
-scan_uri("aaas://" ++ Rest) ->
-    scan_fqdn(Rest, #diameter_uri{type = aaas}).
-
-scan_fqdn(S, U) ->
-    {[_|_] = F, Rest} = lists:splitwith(fun is_fqdn/1, S),
-    scan_opt_port(Rest, U#diameter_uri{fqdn = F}).
-
-scan_opt_port(":" ++ S, U) ->
-    {[_|_] = P, Rest} = lists:splitwith(fun is_digit/1, S),
-    scan_opt_transport(Rest, U#diameter_uri{port = list_to_integer(P)});
-scan_opt_port(S, U) ->
-    scan_opt_transport(S, U).
-
-scan_opt_transport(";transport=" ++ S, U) ->
-    {P, Rest} = transport(S),
-    scan_opt_protocol(Rest, U#diameter_uri{transport = P});
-scan_opt_transport(S, U) ->
-    scan_opt_protocol(S, U).
-
-scan_opt_protocol(";protocol=" ++ S, U) ->
-    {P, ""} = protocol(S),
-    U#diameter_uri{protocol = P};
-scan_opt_protocol("", U) ->
-    U.
-
-transport("tcp" ++ S) ->
-    {tcp, S};
-transport("sctp" ++ S) ->
-    {sctp, S};
-transport("udp" ++ S) ->
-    {udp, S}.
-
-protocol("diameter" ++ S) ->
-    {diameter, S};
-protocol("radius" ++ S) ->
-    {radius, S};
-protocol("tacacs+" ++ S) ->
-    {'tacacs+', S}.
-
-is_fqdn(C) ->
-    is_digit(C) orelse is_alpha(C) orelse C == $. orelse C == $-.
-
-is_alpha(C) ->
-    ($a =< C andalso C =< $z) orelse ($A =< C andalso C =< $Z).
-
-is_digit(C) ->
-    $0 =< C andalso C =< $9.
+scan_uri(Bin) ->
+    RE = "^(aaas?)://"
+         "([-a-zA-Z0-9.]+)"
+         "(:([0-9]+))?"
+         "(;transport=(tcp|sctp|udp))?"
+         "(;protocol=(diameter|radius|tacacs\\+))?$",
+    {match, [A, DN, PN, T, P]} = re:run(Bin,
+                                        RE,
+                                        [{capture, [1,2,4,6,8], binary}]),
+    #diameter_uri{port = PN0,
+                  transport = T0,
+                  protocol = P0}
+        = #diameter_uri{},
+    #diameter_uri{type = to_atom(A),
+                  fqdn = from_bin(DN),
+                  port = to_int(PN, PN0),
+                  transport = to_atom(T, T0),
+                  protocol = to_atom(P, P0)}.
+
+from_bin(B) ->
+    case diameter_codec:getopt(string_decode) of
+        true ->
+            binary_to_list(B);
+        false ->
+            B
+    end.
+
+to_int(<<>>, N) ->
+    N;
+to_int(B, _) ->
+    binary_to_integer(B).
+
+to_atom(<<>>, A) ->
+    A;
+to_atom(B, _) ->
+    to_atom(B).
+
+to_atom(B) ->
+    binary_to_atom(B, latin1).
diff --git a/lib/diameter/src/base/diameter_watchdog.erl b/lib/diameter/src/base/diameter_watchdog.erl
index ff51c6dcf7..fec6fb6107 100644
--- a/lib/diameter/src/base/diameter_watchdog.erl
+++ b/lib/diameter/src/base/diameter_watchdog.erl
@@ -124,14 +124,15 @@ i({Ack, T, Pid, {RecvData,
     wait(Ack, Pid),
     {_, Seed} = diameter_lib:seed(),
     random:seed(Seed),
-    putr(restart, {T, Opts, Svc}),  %% save seeing it in trace
-    putr(dwr, dwr(Caps)),           %%
+    putr(restart, {T, Opts, Svc, SvcOpts}),  %% save seeing it in trace
+    putr(dwr, dwr(Caps)),                    %%
+    diameter_codec:setopts([{string_decode, false}]),
     {_,_} = Mask = proplists:get_value(sequence, SvcOpts),
     Restrict = proplists:get_value(restrict_connections, SvcOpts),
     Nodes = restrict_nodes(Restrict),
     Dict0 = common_dictionary(Apps),
     #watchdog{parent = Pid,
-              transport = start(T, Opts, Mask, Nodes, Dict0, Svc),
+              transport = start(T, Opts, SvcOpts, Nodes, Dict0, Svc),
               tw = proplists:get_value(watchdog_timer,
                                        Opts,
                                        ?DEFAULT_TW_INIT),
@@ -166,11 +167,11 @@ config({okay, N}, Rec)
   when ?IS_NATURAL(N) ->
     Rec#config{okay = N}.
 
-%% start/5
+%% start/6
 
-start(T, Opts, Mask, Nodes, Dict0, Svc) ->
+start(T, Opts, SvcOpts, Nodes, Dict0, Svc) ->
     {_MRef, Pid}
-        = diameter_peer_fsm:start(T, Opts, {Mask, Nodes, Dict0, Svc}),
+        = diameter_peer_fsm:start(T, Opts, {SvcOpts, Nodes, Dict0, Svc}),
     Pid.
 
 %% common_dictionary/1
@@ -320,7 +321,7 @@ code_change(_, State, _) ->
 %% expiry; or another watchdog is saying the same after reestablishing
 %% a connection previously had by this one.
 transition(close, #watchdog{}) ->
-    {{accept, _}, _, _} = getr(restart), %% assert
+    {accept, _} = role(), %% assert
     stop;
 
 %% Service is asking for the peer to be taken down gracefully.
@@ -370,7 +371,7 @@ transition({open, TPid, Hosts, _} = Open,
                      restrict = {_,R},
                      config = #config{suspect = OS}}
            = S) ->
-    case okay(getr(restart), Hosts, R) of
+    case okay(role(), Hosts, R) of
         okay ->
             set_watchdog(S#watchdog{status = okay,
                                     num_dwa = OS});
@@ -424,7 +425,7 @@ transition({'DOWN', _, process, TPid, _Reason} = D,
            = S0) ->
     S = S0#watchdog{pending = false,
                     transport = undefined},
-    {{M,_}, _, _} = getr(restart),
+    {M,_} = role(),
 
     %% Close an accepting watchdog immediately if there's no
     %% restriction on the number of connections to the same peer: the
@@ -491,7 +492,7 @@ encode(dwa, Dict0, #diameter_packet{header = H, transport_data = TD}
 
 %% okay/3
 
-okay({{accept, Ref}, _, _}, Hosts, Restrict) ->
+okay({accept, Ref}, Hosts, Restrict) ->
     T = {?MODULE, connection, Ref, Hosts},
     diameter_reg:add(T),
     if Restrict ->
@@ -502,7 +503,7 @@ okay({{accept, Ref}, _, _}, Hosts, Restrict) ->
 %% Register before matching so that at least one of two registering
 %% processes will match the other.
 
-okay({{connect, _}, _, _}, _, _) ->
+okay({connect, _}, _, _) ->
     okay.
 
 %% okay/2
@@ -517,6 +518,11 @@ okay(C) ->
     [_|_] = [send(P, close) || {_,P} <- C, self() /= P],
     reopen.
 
+%% role/0
+
+role() ->
+    element(1, getr(restart)).
+
 %% set_watchdog/1
 
 set_watchdog(#watchdog{tw = TwInit,
@@ -573,11 +579,18 @@ rcv('DWR', Pkt, #watchdog{transport = TPid,
     DPkt = diameter_codec:decode(Dict0, Pkt),
     diameter_traffic:incr(recv, DPkt, TPid, Dict0),
     diameter_traffic:incr_error(recv, DPkt, TPid, Dict0),
-    EPkt = encode(dwa, Dict0, Pkt),
+    #diameter_packet{header = H,
+                     transport_data = T,
+                     bin = Bin}
+        = EPkt
+        = encode(dwa, Dict0, Pkt),
     diameter_traffic:incr(send, EPkt, TPid, Dict0),
     diameter_traffic:incr_rc(send, EPkt, TPid, Dict0),
 
-    send(TPid, {send, EPkt}),
+    %% Strip potentially large message terms.
+    send(TPid, {send, #diameter_packet{header = H,
+                                       transport_data = T,
+                                       bin = Bin}}),
     ?LOG(send, 'DWA');
 
 rcv('DWA', Pkt, #watchdog{transport = TPid,
@@ -796,26 +809,28 @@ restart(S) ->  %% reconnect has won race with timeout
 %% state down rather then initial when receiving notification of an
 %% open connection.
 
-restart({{connect, _} = T, Opts, Svc},
+restart({T, Opts, Svc}, S) ->  %% put in old code
+    restart({T, Opts, Svc, []}, S);
+
+restart({{connect, _} = T, Opts, Svc, SvcOpts},
         #watchdog{parent = Pid,
-                  sequence = Mask,
                   restrict = {R,_},
                   dictionary = Dict0}
         = S) ->
     send(Pid, {reconnect, self()}),
     Nodes = restrict_nodes(R),
-    S#watchdog{transport = start(T, Opts, Mask, Nodes, Dict0, Svc),
+    S#watchdog{transport = start(T, Opts, SvcOpts, Nodes, Dict0, Svc),
                restrict = {R, lists:member(node(), Nodes)}};
 
 %% No restriction on the number of connections to the same peer: just
 %% die. Note that a state machine never enters state REOPEN in this
 %% case.
-restart({{accept, _}, _, _}, #watchdog{restrict = {_, false}}) ->
+restart({{accept, _}, _, _, _}, #watchdog{restrict = {_, false}}) ->
     stop;  %% 'DOWN' was in old code: 'close' was not sent
 
 %% Otherwise hang around until told to die, either by the service or
 %% by another watchdog.
-restart({{accept, _}, _, _}, S) ->
+restart({{accept, _}, _, _, _}, S) ->
     S.
 
 %% Don't currently use Opts/Svc in the accept case.
diff --git a/lib/diameter/test/diameter_config_SUITE.erl b/lib/diameter/test/diameter_config_SUITE.erl
index e61d3aea0e..e2ac2cedcb 100644
--- a/lib/diameter/test/diameter_config_SUITE.erl
+++ b/lib/diameter/test/diameter_config_SUITE.erl
@@ -82,6 +82,9 @@
            [false],
            [[node(), node()]]],
           [[x]]},
+         {string_decode,
+          [[true], [false]],
+          [[0], [x]]},
          {invalid_option,  %% invalid service options are rejected
           [],
           [[x],
diff --git a/lib/diameter/test/diameter_traffic_SUITE.erl b/lib/diameter/test/diameter_traffic_SUITE.erl
index 9822b95301..10c58ab6e7 100644
--- a/lib/diameter/test/diameter_traffic_SUITE.erl
+++ b/lib/diameter/test/diameter_traffic_SUITE.erl
@@ -122,8 +122,6 @@
 
 -define(ADDR, {127,0,0,1}).
 
--define(CLIENT, "CLIENT").
--define(SERVER, "SERVER").
 -define(REALM, "erlang.org").
 -define(HOST(Host, Realm), Host ++ [$.|Realm]).
 
@@ -141,11 +139,19 @@
 %% Which common dictionary to use in the clients.
 -define(RFCS, [rfc3588, rfc6733]).
 
+%% Whether to decode stringish Diameter types to strings, or leave
+%% them as binary.
+-define(STRING_DECODES, [true, false]).
+
 -record(group,
-        {client_encoding,
+        {client_service,
+         client_encoding,
          client_dict0,
+         client_strings,
+         server_service,
          server_encoding,
-         server_container}).
+         server_container,
+         server_strings}).
 
 %% Not really what we should be setting unless the message is sent in
 %% the common application but diameter doesn't care.
@@ -166,7 +172,7 @@
         ?answer_message(_, ResultCode)).
 
 %% Config for diameter:start_service/2.
--define(SERVICE(Name),
+-define(SERVICE(Name, Decode),
         [{'Origin-Host', Name ++ "." ++ ?REALM},
          {'Origin-Realm', ?REALM},
          {'Host-IP-Address', [?ADDR]},
@@ -175,6 +181,7 @@
          {'Auth-Application-Id', [?DIAMETER_APP_ID_COMMON]},
          {'Acct-Application-Id', [?DIAMETER_APP_ID_ACCOUNTING]},
          {restrict_connections, false},
+         {string_decode, Decode},
          {spawn_opt, [{min_heap_size, 5000}]}
          | [{application, [{dictionary, D},
                            {module, ?MODULE},
@@ -227,28 +234,53 @@ suite() ->
     [{timetrap, {seconds, 60}}].
 
 all() ->
-    [start, start_services, add_transports, result_codes]
-        ++ [{group, ?util:name([R,D,A,C]), P} || R <- ?ENCODINGS,
-                                                 D <- ?RFCS,
-                                                 A <- ?ENCODINGS,
-                                                 C <- ?CONTAINERS,
-                                                 P <- [[], [parallel]]]
-        ++ [outstanding, remove_transports, empty, stop_services, stop].
+    [start, result_codes, {group, traffic}, outstanding, empty, stop].
 
 groups() ->
     Ts = tc(),
-    [{?util:name([R,D,A,C]), [], Ts} || R <- ?ENCODINGS,
-                                        D <- ?RFCS,
-                                        A <- ?ENCODINGS,
-                                        C <- ?CONTAINERS].
+    [{?util:name([R,D,A,C]), [parallel], Ts} || R <- ?ENCODINGS,
+                                                D <- ?RFCS,
+                                                A <- ?ENCODINGS,
+                                                C <- ?CONTAINERS]
+        ++
+        [{?util:name([R,D,A,C,SD,CD]),
+          [],
+          [start_services,
+           add_transports,
+           result_codes,
+           {group, ?util:name([R,D,A,C])},
+           remove_transports,
+           stop_services]}
+         || R <- ?ENCODINGS,
+            D <- ?RFCS,
+            A <- ?ENCODINGS,
+            C <- ?CONTAINERS,
+            SD <- ?STRING_DECODES,
+            CD <- ?STRING_DECODES]
+        ++
+        [{traffic, [parallel], [{group, ?util:name([R,D,A,C,SD,CD])}
+                                || R <- ?ENCODINGS,
+                                   D <- ?RFCS,
+                                   A <- ?ENCODINGS,
+                                   C <- ?CONTAINERS,
+                                   SD <- ?STRING_DECODES,
+                                   CD <- ?STRING_DECODES]}].
 
 init_per_group(Name, Config) ->
-    [R,D,A,C] = ?util:name(Name),
-    G = #group{client_encoding = R,
-               client_dict0 = dict0(D),
-               server_encoding = A,
-               server_container = C},
-    [{group, G} | Config].
+    case ?util:name(Name) of
+        [R,D,A,C,SD,CD] ->
+            G = #group{client_service = [$C|?util:unique_string()],
+                       client_encoding = R,
+                       client_dict0 = dict0(D),
+                       client_strings = CD,
+                       server_service = [$S|?util:unique_string()],
+                       server_encoding = A,
+                       server_container = C,
+                       server_strings = SD},
+            [{group, G} | Config];
+        _ ->
+            Config
+    end.
 
 end_per_group(_, _) ->
     ok.
@@ -319,18 +351,26 @@ tc() ->
 start(_Config) ->
     ok = diameter:start().
 
-start_services(_Config) ->
-    ok = diameter:start_service(?SERVER, ?SERVICE(?SERVER)),
-    ok = diameter:start_service(?CLIENT, [{sequence, ?CLIENT_MASK}
-                                          | ?SERVICE(?CLIENT)]).
+start_services(Config) ->
+    #group{client_service = CN,
+           client_strings = CD,
+           server_service = SN,
+           server_strings = SD}
+        = group(Config),
+    ok = diameter:start_service(SN, ?SERVICE(SN, SD)),
+    ok = diameter:start_service(CN, [{sequence, ?CLIENT_MASK}
+                                     | ?SERVICE(CN, CD)]).
 
 add_transports(Config) ->
-    LRef = ?util:listen(?SERVER,
+    #group{client_service = CN,
+           server_service = SN}
+        = group(Config), 
+    LRef = ?util:listen(SN,
                         tcp,
                         [{capabilities_cb, fun capx/2},
                          {spawn_opt, [{min_heap_size, 8096}]},
                          {applications, apps(rfc3588)}]),
-    Cs = [?util:connect(?CLIENT,
+    Cs = [?util:connect(CN,
                         tcp,
                         LRef,
                         [{id, Id},
@@ -354,12 +394,18 @@ outstanding(_Config) ->
                is_atom(element(1,T))].
 
 remove_transports(Config) ->
+    #group{client_service = CN,
+           server_service = SN}
+        = group(Config),
     [LRef | Cs] = ?util:read_priv(Config, "transport"),
-    [?util:disconnect(?CLIENT, C, ?SERVER, LRef) || C <- Cs].
+    [?util:disconnect(CN, C, SN, LRef) || C <- Cs].
 
-stop_services(_Config) ->
-    ok = diameter:stop_service(?CLIENT),
-    ok = diameter:stop_service(?SERVER).
+stop_services(Config) ->
+    #group{client_service = CN,
+           server_service = SN}
+        = group(Config),
+    ok = diameter:stop_service(CN),
+    ok = diameter:stop_service(SN).
 
 %% Ensure even transports have been removed from request table.
 empty(_Config) ->
@@ -439,8 +485,9 @@ send_arbitrary(Config) ->
     ['ASA', _SessionId, {'Result-Code', ?SUCCESS} | Avps]
         = call(Config, Req),
     {'AVP', [#diameter_avp{name = 'Product-Name',
-                           value = "XXX"}]}
-        = lists:last(Avps).
+                           value = V}]}
+        = lists:last(Avps),
+    "XXX" = string(V, Config).
 
 %% Send an unknown AVP (to some client) and check that it comes back.
 send_unknown(Config) ->
@@ -594,9 +641,11 @@ send_nopeer(Config) ->
     {error, no_connection} = call(Config, Req, [{extra, [?EXTRA]}]).
 
 %% Send something on an unconfigured application.
-send_noapp(_Config) ->
+send_noapp(Config) ->
+    #group{client_service = CN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT}],
-    {error, no_connection} = diameter:call(?CLIENT, unknown_alias, Req).
+    {error, no_connection} = diameter:call(CN, unknown_alias, Req).
 
 %% Send something that's discarded by prepare_request.
 send_discard(Config) ->
@@ -608,8 +657,10 @@ send_any_1(Config) ->
     Req = ['STR', {'Termination-Cause', ?LOGOUT}],
     {error, no_connection} = call(Config, Req, [{filter, {any, []}}]).
 send_any_2(Config) ->
+    #group{server_service = SN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT},
-                  {'Destination-Host', [?HOST(?SERVER, "unknown.org")]}],
+                  {'Destination-Host', [?HOST(SN, "unknown.org")]}],
     ?answer_message(?UNABLE_TO_DELIVER)
         = call(Config, Req, [{filter, {any, [host, realm]}}]).
 
@@ -621,8 +672,10 @@ send_all_1(Config) ->
         = call(Config, Req, [{filter, {all, [{host, any},
                                              {realm, Realm}]}}]).
 send_all_2(Config) ->
+    #group{server_service = SN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT},
-                  {'Destination-Host', [?HOST(?SERVER, "unknown.org")]}],
+                  {'Destination-Host', [?HOST(SN, "unknown.org")]}],
     {error, no_connection}
         = call(Config, Req, [{filter, {all, [host, realm]}}]).
 
@@ -655,8 +708,10 @@ send_encode_error(Config) ->
 
 %% Send with filtering and expect success.
 send_destination_1(Config) ->
+    #group{server_service = SN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT},
-                  {'Destination-Host', [?HOST(?SERVER, ?REALM)]}],
+                  {'Destination-Host', [?HOST(SN, ?REALM)]}],
     ['STA', _SessionId, {'Result-Code', ?SUCCESS} | _]
         = call(Config, Req, [{filter, {all, [host, realm]}}]).
 send_destination_2(Config) ->
@@ -672,8 +727,10 @@ send_destination_3(Config) ->
     {error, no_connection}
         = call(Config, Req, [{filter, {all, [host, realm]}}]).
 send_destination_4(Config) ->
+    #group{server_service = SN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT},
-                  {'Destination-Host', [?HOST(?SERVER, "unknown.org")]}],
+                  {'Destination-Host', [?HOST(SN, "unknown.org")]}],
     {error, no_connection}
         = call(Config, Req, [{filter, {all, [host, realm]}}]).
 
@@ -685,8 +742,10 @@ send_destination_5(Config) ->
     ?answer_message(?REALM_NOT_SERVED)
         = call(Config, Req).
 send_destination_6(Config) ->
+    #group{server_service = SN}
+        = group(Config),
     Req = ['STR', {'Termination-Cause', ?LOGOUT},
-                  {'Destination-Host', [?HOST(?SERVER, "unknown.org")]}],
+                  {'Destination-Host', [?HOST(SN, "unknown.org")]}],
     ?answer_message(?UNABLE_TO_DELIVER)
         = call(Config, Req).
 
@@ -748,16 +807,31 @@ send_anything(Config) ->
 
 %% ===========================================================================
 
+group(Config) ->
+    #group{} = proplists:get_value(group, Config).
+
+string(V, Config) ->
+    #group{client_strings = B} = group(Config),
+    decode(V,B).
+
+decode(S, true)
+  when is_list(S) ->
+    S;
+decode(B, false)
+  when is_binary(B) ->
+    binary_to_list(B).
+
 call(Config, Req) ->
     call(Config, Req, []).
 
 call(Config, Req, Opts) ->
     Name = proplists:get_value(testcase, Config),
-    #group{client_encoding = ReqEncoding,
+    #group{client_service = CN,
+           client_encoding = ReqEncoding,
            client_dict0 = Dict0}
         = Group
-        = proplists:get_value(group, Config),
-    diameter:call(?CLIENT,
+        = group(Config),
+    diameter:call(CN,
                   dict(Req, Dict0),
                   msg(Req, ReqEncoding, Dict0),
                   [{extra, [{Name, Group}, diameter_lib:now()]} | Opts]).
@@ -844,35 +918,38 @@ peer_down(_SvcName, _Peer, State) ->
 
 %% pick_peer/6-7
 
-pick_peer(Peers, _, ?CLIENT, _State, {Name, Group}, _)
+pick_peer(Peers, _, [$C|_], _State, {Name, Group}, _)
   when Name /= send_detach ->
     find(Group, Peers).
 
-pick_peer(_Peers, _, ?CLIENT, _State, {send_nopeer, _}, _, ?EXTRA) ->
+pick_peer(_Peers, _, [$C|_], _State, {send_nopeer, _}, _, ?EXTRA) ->
     false;
 
-pick_peer(Peers, _, ?CLIENT, _State, {send_detach, Group}, _, {_,_}) ->
+pick_peer(Peers, _, [$C|_], _State, {send_detach, Group}, _, {_,_}) ->
     find(Group, Peers).
 
-find(#group{server_encoding = A, server_container = C}, Peers) ->
+find(#group{client_service = CN,
+            server_encoding = A,
+            server_container = C},
+     Peers) ->
     Id = {A,C},
-    [P] = [P || P <- Peers, id(Id, P)],
+    [P] = [P || P <- Peers, id(Id, P, CN)],
     {ok, P}.
 
-id(Id, {Pid, _Caps}) ->
+id(Id, {Pid, _Caps}, SvcName) ->
     [{ref, _}, {type, _}, {options, Opts} | _]
-        = diameter:service_info(?CLIENT, Pid),
+        = diameter:service_info(SvcName, Pid),
     lists:member({id, Id}, Opts).
 
 %% prepare_request/5-6
 
-prepare_request(_Pkt, ?CLIENT, {_Ref, _Caps}, {send_discard, _}, _) ->
+prepare_request(_Pkt, [$C|_], {_Ref, _Caps}, {send_discard, _}, _) ->
     {discard, unprepared};
 
-prepare_request(Pkt, ?CLIENT, {_Ref, Caps}, {Name, Group}, _) ->
+prepare_request(Pkt, [$C|_], {_Ref, Caps}, {Name, Group}, _) ->
     {send, prepare(Pkt, Caps, Name, Group)}.
 
-prepare_request(Pkt, ?CLIENT, {_Ref, Caps}, {send_detach, Group}, _, _) ->
+prepare_request(Pkt, [$C|_], {_Ref, Caps}, {send_detach, Group}, _, _) ->
     {eval_packet, {send, prepare(Pkt, Caps, Group)}, [fun log/2, detach]}.
 
 log(#diameter_packet{bin = Bin} = P, T)
@@ -1043,10 +1120,10 @@ prepare_retransmit(_Pkt, false, _Peer, _Name, _Group) ->
 
 %% handle_answer/6-7
 
-handle_answer(Pkt, Req, ?CLIENT, Peer, {Name, Group}, _) ->
+handle_answer(Pkt, Req, [$C|_], Peer, {Name, Group}, _) ->
     answer(Pkt, Req, Peer, Name, Group).
 
-handle_answer(Pkt, Req, ?CLIENT, Peer, {send_detach = Name, Group}, _, X) ->
+handle_answer(Pkt, Req, [$C|_], Peer, {send_detach = Name, Group}, _, X) ->
     {Pid, Ref} = X,
     Pid ! {Ref, answer(Pkt, Req, Peer, Name, Group)}.
 
@@ -1075,13 +1152,13 @@ app(Req, _, Dict0) ->
 
 %% handle_error/6
 
-handle_error(timeout = Reason, _Req, ?CLIENT, _Peer, _, Time) ->
+handle_error(timeout = Reason, _Req, [$C|_], _Peer, _, Time) ->
     Now = diameter_lib:now(),
     {Reason, {diameter_lib:timestamp(Time),
               diameter_lib:timestamp(Now),
               diameter_lib:micro_diff(Now, Time)}};
 
-handle_error(Reason, _Req, ?CLIENT, _Peer, _, _Time) ->
+handle_error(Reason, _Req, [$C|_], _Peer, _, _Time) ->
     {error, Reason}.
 
 %% handle_request/3
@@ -1089,7 +1166,7 @@ handle_error(Reason, _Req, ?CLIENT, _Peer, _, _Time) ->
 %% Note that diameter will set Result-Code and Failed-AVPs if
 %% #diameter_packet.errors is non-null.
 
-handle_request(#diameter_packet{header = H, msg = M}, ?SERVER, {_Ref, Caps}) ->
+handle_request(#diameter_packet{header = H, msg = M}, _, {_Ref, Caps}) ->
     #diameter_header{end_to_end_id = EI,
                      hop_by_hop_id = HI}
         = H,