Add option to modify Cowboy server name returned in headers

big_tests/tests/rest_client_SUITE.erl

@@ -7,47 +7,46 @@
 -include_lib("common_test/include/ct.hrl").
 
 -import(rest_helper,
-        [assert_inlist/2,
-         assert_notinlist/2,
-         decode_maplist/1,
-         gett/2,
+        [decode_maplist/1,
          gett/3,
-         post/3,
          post/4,
-         putt/3,
          putt/4,
-         delete/2,
          delete/3,
          delete/4]
          ).
 
 -import(muc_light_helper,
         [set_mod_config/3]).
 
--import(escalus_ejabberd, [rpc/3]).
-
 -define(PRT(X, Y), ct:pal("~p: ~p", [X, Y])).
 -define(OK, {<<"200">>, <<"OK">>}).
 -define(CREATED, {<<"201">>, <<"Created">>}).
 -define(NOCONTENT, {<<"204">>, <<"No Content">>}).
 -define(ERROR, {<<"500">>, _}).
 -define(NOT_FOUND, {<<"404">>, _}).
 -define(NOT_IMPLEMENTED, {<<"501">>, _}).
+-define(UNAUTHORIZED, {<<"401">>, <<"Unauthorized">>}).
 -define(MUCHOST, <<"muclight.localhost">>).
 
+%% --------------------------------------------------------------------
+%% Common Test stuff
+%% --------------------------------------------------------------------
+
 all() ->
     [{group, messages},
      {group, muc},
      {group, muc_config},
      {group, roster},
-     {group, messages_with_props}].
+     {group, messages_with_props},
+     {group, security}].
 
 groups() ->
     G = [{messages_with_props, [parallel], message_with_props_test_cases()},
          {messages, [parallel], message_test_cases()},
          {muc, [pararell], muc_test_cases()},
          {muc_config, [], muc_config_cases()},
-         {roster, [parallel], roster_test_cases()}],
+         {roster, [parallel], roster_test_cases()},
+         {security, [], security_test_cases()}],
     ct_helper:repeat_all_until_all_ok(G).
 
 message_test_cases() ->
@@ -106,6 +105,12 @@ message_with_props_test_cases() ->
      msg_with_malformed_props_is_sent_and_delivered_over_xmpp
      ].
 
+security_test_cases() ->
+    [
+     default_http_server_name_is_returned_if_not_changed,
+     non_default_http_server_name_is_returned_if_configured
+    ].
+
 init_per_suite(C) ->
     application:ensure_all_started(shotgun),
     Host = ct:get_config({hosts, mim, domain}),
@@ -158,6 +163,10 @@ end_per_testcase(config_can_be_changed_by_all = CaseName, Config) ->
 end_per_testcase(TC, C) ->
     escalus:end_per_testcase(TC, C).
 
+%% --------------------------------------------------------------------
+%% Test cases
+%% --------------------------------------------------------------------
+
 msg_is_sent_and_delivered_over_xmpp(Config) ->
     escalus:fresh_story(Config, [{alice, 1}, {bob, 1}], fun(Alice, Bob) ->
         M = send_message(alice, Alice, Bob),
@@ -581,7 +590,6 @@ msg_with_malformed_props_can_be_parsed(Config) ->
 
     end).
 
-
 assert_room_messages(RecvMsg, {_ID, _GenFrom, GenMsg}) ->
     escalus:assert(is_chat_message, [maps:get(body, RecvMsg)], GenMsg),
     ok.
@@ -652,7 +660,7 @@ when_config_change(User, RoomID, NewName, NewSubject) ->
     Creds = credentials(User),
     Config = #{name => NewName, subject => NewSubject},
     Path = <<"/rooms/", RoomID/binary, "/config">>,
-    rest_helper:putt(client, Path, Config, Creds).
+    putt(client, Path, Config, Creds).
 
 maybe_wait_for_aff_stanza(#client{} = Client, Invitee) ->
     Stanza = escalus:wait_for_stanza(Client),
@@ -690,7 +698,7 @@ send_message(User, From, To) ->
     BobJID = user_jid(To),
     M = #{to => BobJID, body => <<"hello, ", BobJID/binary, " it's me">>},
     Cred = credentials({User, From}),
-    {{<<"200">>, <<"OK">>}, {Result}} = rest_helper:post(client, <<"/messages">>, M, Cred),
+    {{<<"200">>, <<"OK">>}, {Result}} = post(client, <<"/messages">>, M, Cred),
     ID = proplists:get_value(<<"id">>, Result),
     M#{id => ID, from => AliceJID}.
 
@@ -762,7 +770,7 @@ create_room_with_id_request(Creds, RoomName, Subject, RoomID) ->
     Room = #{name => RoomName,
              subject => Subject},
     Path = <<"/rooms/", RoomID/binary>>,
-    rest_helper:putt(client, Path, Room, Creds).
+    putt(client, Path, Room, Creds).
 
 get_my_rooms(User) ->
     Creds = credentials(User),
@@ -1163,3 +1171,26 @@ room_jid(RoomID, Config) ->
 
 domain(Config) ->
     ?config(muc_light_host, Config).
+
+default_http_server_name_is_returned_if_not_changed(_Config) ->
+    %% GIVEN MIM1 uses default name
+    verify_server_name_in_header(distributed_helper:mim(), <<"Cowboy">>).
+
+non_default_http_server_name_is_returned_if_configured(_Config) ->
+    %% GIVEN MIM2 uses name "Classified"
+    verify_server_name_in_header(distributed_helper:mim2(), <<"Classified">>).
+
+verify_server_name_in_header(Server, ExpectedName) ->
+    % WHEN unathenticated user makes a request to nonexistent path
+    ReqParams = #{
+      role => client,
+      method => <<"GET">>,
+      path => "/contacts/zorro@localhost",
+      body => <<>>,
+      return_headers => true,
+      server => Server
+     },           
+    {?UNAUTHORIZED, Headers2, _} = rest_helper:make_request(ReqParams),
+    % THEN expected server name is returned
+    ExpectedName = proplists:get_value(<<"server">>, Headers2).
+

big_tests/tests/rest_helper.erl

@@ -15,6 +15,7 @@
     delete/2,
     delete/3,
     delete/4,
+    make_request/1,
     maybe_enable_mam/3,
     maybe_disable_mam/2,
     maybe_skip_mam_test_cases/3,
@@ -32,6 +33,15 @@
 -define(PATHPREFIX, <<"/api">>).
 
 -type role() :: admin | client.
+-type credentials() :: {Username :: binary(), Password :: binary()}.
+-type request_params() :: #{
+        role := role(),
+        method := binary(),
+        creds => credentials(),
+        path := binary(),
+        body := binary(),
+        return_headers := boolean(),
+        server := atom() }.
 
 %%--------------------------------------------------------------------
 %% Helpers
@@ -87,51 +97,66 @@ assert_notinmaplist([K|Keys], Map, L, Orig) ->
 
 
 gett(Role, Path) ->
-    make_request(Role, <<"GET">>, Path).
+    make_request(#{ role => Role, method => <<"GET">>, path => Path }).
 
 post(Role, Path, Body) ->
-    make_request(Role, <<"POST">>, Path, Body).
+    make_request(#{ role => Role, method => <<"POST">>, path => Path, body => Body }).
 
 putt(Role, Path, Body) ->
-    make_request(Role, <<"PUT">>, Path, Body).
+    make_request(#{ role => Role, method => <<"PUT">>, path => Path, body => Body }).
 
 delete(Role, Path) ->
-    make_request(Role, <<"DELETE">>, Path).
+    make_request(#{ role => Role, method => <<"DELETE">>, path => Path }).
 
--spec gett(role(), Path :: string()|binary(), Cred :: {Username :: binary(), Password :: binary()}) -> term().
 gett(Role, Path, Cred) ->
-    make_request(Role, {<<"GET">>, Cred}, Path).
+    make_request(#{ role => Role, method => <<"GET">>, creds => Cred, path => Path}).
 
 post(Role, Path, Body, Cred) ->
-    make_request(Role, {<<"POST">>, Cred}, Path, Body).
+    make_request(#{ role => Role, method => <<"POST">>, creds => Cred, path => Path, body => Body }).
 
 putt(Role, Path, Body, Cred) ->
-    make_request(Role, {<<"PUT">>, Cred}, Path, Body).
+    make_request(#{ role => Role, method => <<"PUT">>, creds => Cred, path => Path, body => Body }).
 
 delete(Role, Path, Cred) ->
-    make_request(Role, {<<"DELETE">>, Cred}, Path).
+    make_request(#{ role => Role, method => <<"DELETE">>, creds => Cred, path => Path }).
 
 delete(Role, Path, Cred, Body) ->
-    make_request(Role, {<<"DELETE">>, Cred}, Path, Body).
-
-
-
-make_request(Role, Method, Path) ->
-    make_request(Role, Method, Path, <<"">>).
-
-make_request(Role, Method, Path, ReqBody) when is_map(ReqBody) ->
-    make_request(Role, Method, Path, jiffy:encode(ReqBody));
-make_request(Role, Method, Path, ReqBody) when not is_binary(Path) ->
-    make_request(Role, Method, list_to_binary(Path), ReqBody);
-make_request(Role, Method, Path, ReqBody) ->
-    CPath = <<?PATHPREFIX/binary, Path/binary>>,
-    {Code, RespBody} = case fusco_request(Role, Method, CPath, ReqBody) of
-                           {RCode, _, Body, _, _} ->
-                               {RCode, Body};
-                           {RCode, _, Body, _, _, _} ->
-                               {RCode, Body}
-                       end,
-    {Code, decode(RespBody)}.
+    make_request(#{ role => Role, method => <<"DELETE">>, creds => Cred, path => Path, body => Body }).
+
+-spec make_request(request_params()) ->
+    {{Number :: binary(), Text :: binary()},
+     Headers :: [{binary(), binary()}],
+     Body :: map() | binary()}. 
+make_request(#{ return_headers := true } = Params) ->
+    NormalizedParams = normalize_path(normalize_body(fill_default_server(Params))),
+    case fusco_request(NormalizedParams) of
+        {RCode, RHeaders, Body, _, _} ->
+            {RCode, normalize_headers(RHeaders), decode(Body)};
+        {RCode, RHeaders, Body, _, _, _} ->
+            {RCode, normalize_headers(RHeaders), decode(Body)}
+    end;
+make_request(#{ return_headers := false } = Params) ->
+    {Code, _, Body} = make_request(Params#{ return_headers := true }),
+    {Code, Body};
+make_request(Params) ->
+    make_request(Params#{ return_headers => false }).
+
+normalize_path(#{ path := Path } = Params) when not is_binary(Path) ->
+    normalize_path(Params#{ path := list_to_binary(Path) });
+normalize_path(#{ path := Path } = Params) ->
+    Params#{ path := <<?PATHPREFIX/binary, Path/binary>> }.
+
+normalize_body(#{ body := Body } = Params) when is_map(Body) ->
+    Params#{ body := jiffy:encode(Body) };
+normalize_body(#{ body := Body } = Params) when is_binary(Body) ->
+    Params;
+normalize_body(Params) ->
+    Params#{ body => <<>> }.
+
+fill_default_server(#{ server := _Server } = Params) ->
+    Params;
+fill_default_server(Params) ->
+    Params#{ server => mim() }.
 
 decode(<<>>) ->
     <<"">>;
@@ -143,14 +168,21 @@ decode(RespBody) ->
             RespBody
     end.
 
+normalize_headers(Headers) ->
+    lists:map(fun({K, V}) when is_binary(V) -> {K, V};
+                 ({K, V}) when is_list(V) -> {K, iolist_to_binary(V)} end, Headers).
+
 %% a request specyfying credentials is directed to client http listener
-fusco_request(Role, {Method, {User, Password}}, Path, Body) ->
-    Basic = list_to_binary("Basic " ++ base64:encode_to_string(to_list(User) ++ ":"++ to_list(Password))),
+fusco_request(#{ role := Role, method := Method, creds := {User, Password},
+                 path := Path, body := Body, server := Server }) ->
+    EncodedAuth = base64:encode_to_string(to_list(User) ++ ":"++ to_list(Password)),
+    Basic = list_to_binary("Basic " ++ EncodedAuth),
     Headers = [{<<"authorization">>, Basic}],
-    fusco_request(Method, Path, Body, Headers, get_port(Role), get_ssl_status(Role));
+    fusco_request(Method, Path, Body, Headers,
+                  get_port(Role, Server), get_ssl_status(Role, Server));
 %% without them it is for admin (secure) interface
-fusco_request(Role, Method, Path, Body) ->
-    fusco_request(Method, Path, Body, [], get_port(Role), get_ssl_status(Role)).
+fusco_request(#{ role := Role, method := Method, path := Path, body := Body, server := Server }) ->
+    fusco_request(Method, Path, Body, [], get_port(Role, Server), get_ssl_status(Role, Server)).
 
 fusco_request(Method, Path, Body, HeadersIn, Port, SSL) ->
     {ok, Client} = fusco_cp:start_link({"localhost", Port, SSL}, [], 1),
@@ -159,20 +191,22 @@ fusco_request(Method, Path, Body, HeadersIn, Port, SSL) ->
     fusco_cp:stop(Client),
     Result.
 
--spec get_port(role()) -> Port :: integer().
-get_port(Role) -> 
-    Listeners = rpc(mim(), ejabberd_config, get_local_option, [listen]),
-    [{PortIpNet, ejabberd_cowboy, _Opts}] = lists:filter(fun(Config) -> is_roles_config(Config, Role) end, Listeners),
+-spec get_port(Role :: role(), Server :: atom()) -> Port :: integer().
+get_port(Role, Server) -> 
+    Listeners = rpc(Server, ejabberd_config, get_local_option, [listen]),
+    [{PortIpNet, ejabberd_cowboy, _Opts}] =
+        lists:filter(fun(Config) -> is_roles_config(Config, Role) end, Listeners),
     case PortIpNet of
         {Port, _Host, _Net} -> Port;
         {Port, _Host} -> Port;
         Port -> Port
     end.
 
--spec get_ssl_status(role()) -> boolean().
-get_ssl_status(Role) ->
-    Listeners = rpc(mim(), ejabberd_config, get_local_option, [listen]),
-    [{_PortIpNet, _Module, Opts}] = lists:filter(fun (Opts) -> is_roles_config(Opts, Role) end, Listeners),
+-spec get_ssl_status(Role :: role(), Server :: atom()) -> boolean().
+get_ssl_status(Role, Server) ->
+    Listeners = rpc(Server, ejabberd_config, get_local_option, [listen]),
+    [{_PortIpNet, _Module, Opts}] =
+        lists:filter(fun (Opts) -> is_roles_config(Opts, Role) end, Listeners),
     lists:keymember(ssl, 1, Opts).
 
 % @doc Changes the control credentials for admin by restarting the listener
@@ -403,4 +437,4 @@ make_malformed_msg_stanza_with_props(ToJID,MsgID) ->
                     <value type='long'>1234567890</value>
                 </property2>
             </properties>
-        </message>">>).
+        </message>">>).

doc/Advanced-configuration.md

@@ -20,7 +20,7 @@ Retaining the default layout is recommended so that the experienced MongooseIM u
 
 ## Options
 
-* All options except `hosts`, `host`, `host_config`, `listen` and `outgoing_connections` and  can be used in the `host_config` tuple.
+* All options except `hosts`, `host`, `host_config`, `listen` and `outgoing_connections` may be used in the `host_config` tuple.
 
 * There are two kinds of local options - those that are kept separately for each domain in the config file (defined inside `host_config`) and the options local for a node in the cluster.
 
@@ -351,6 +351,12 @@ There are some additional options that influence all database connections in the
     * **Syntax:** `{replaced_wait_timeout, TimeInMilliseconds}`
     * **Default:** `2000`
 
+* **cowboy_server_name** (local)
+    * **Description:** If configured, replaces Cowboy's default name returned in the `server` HTTP response header. It may be used for extra security, as it makes it harder for the malicious user to learn what HTTP software is running under a specific port. This option applies to **all** listeners started by the `ejabberd_cowboy` module.
+    * **Syntax:** `{cowboy_server_name, NewName}`
+    * **Default:** no value, i.e. `Cowboy` is used as a header value
+    * **Example:** `{cowboy_server_name, "Apache"}`
+
 ### Modules
 
 For a specific configuration, please refer to [Modules](advanced-configuration/Modules.md) page.

rel/files/mongooseim.cfg

@@ -646,6 +646,8 @@
 
 {all_metrics_are_global, {{{all_metrics_are_global}}} }.
 
+{{{cowboy_server_name}}}
+
 %%%.   ========
 %%%'   SERVICES
 

rel/mim2.vars.config

@@ -44,6 +44,7 @@
     "                {password, \"secret\"}\n"
     "           ]}"}.
 {all_metrics_are_global, true}.
+{cowboy_server_name, "{cowboy_server_name, \"Classified\"}."}.
 {c2s_dhfile, ",{dhfile, \"priv/ssl/fake_dh_server.pem\"}"}.
 {s2s_dhfile, ",{dhfile, \"priv/ssl/fake_dh_server.pem\"}"}.
 

src/config/mongoose_config_parser.erl

@@ -298,6 +298,8 @@ process_term(Term, State) ->
             add_option(sasl_mechanisms, Mechanisms, State);
         {all_metrics_are_global, Value} ->
             add_option(all_metrics_are_global, Value, State);
+        {cowboy_server_name, Value} ->
+            add_option(cowboy_server_name, Value, State);
         {services, Value} ->
             add_option(services, Value, State);
         {_Opt, _Val} ->