%% %% %CopyrightBegin% %% %% Copyright Ericsson AB 2010-2017. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. %% You may obtain a copy of the License at %% %% http://www.apache.org/licenses/LICENSE-2.0 %% %% Unless required by applicable law or agreed to in writing, software %% distributed under the License is distributed on an "AS IS" BASIS, %% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %% See the License for the specific language governing permissions and %% limitations under the License. %% %% %CopyrightEnd% %% %% %% Tests of traffic between two Diameter nodes, one client, one server. %% -module(diameter_traffic_SUITE). -export([suite/0, all/0, groups/0, init_per_suite/1, end_per_suite/1, init_per_group/2, end_per_group/2, init_per_testcase/2, end_per_testcase/2]). %% testcases -export([start/1, start_services/1, add_transports/1, result_codes/1, send_ok/1, send_nok/1, send_eval/1, send_bad_answer/1, send_protocol_error/1, send_experimental_result/1, send_arbitrary/1, send_unknown/1, send_unknown_short/1, send_unknown_mandatory/1, send_unknown_short_mandatory/1, send_noreply/1, send_grouped_error/1, send_unsupported/1, send_unsupported_app/1, send_error_bit/1, send_unsupported_version/1, send_long_avp_length/1, send_short_avp_length/1, send_zero_avp_length/1, send_invalid_avp_length/1, send_invalid_reject/1, send_unexpected_mandatory_decode/1, send_unexpected_mandatory/1, send_long/1, send_maxlen/1, send_nopeer/1, send_noapp/1, send_discard/1, send_any_1/1, send_any_2/1, send_all_1/1, send_all_2/1, send_timeout/1, send_error/1, send_detach/1, send_encode_error/1, send_destination_1/1, send_destination_2/1, send_destination_3/1, send_destination_4/1, send_destination_5/1, send_destination_6/1, send_bad_option_1/1, send_bad_option_2/1, send_bad_filter_1/1, send_bad_filter_2/1, send_bad_filter_3/1, send_bad_filter_4/1, send_multiple_filters_1/1, send_multiple_filters_2/1, send_multiple_filters_3/1, send_anything/1, remove_transports/1, empty/1, stop_services/1, stop/1]). %% diameter callbacks -export([peer_up/3, peer_down/3, pick_peer/6, pick_peer/7, prepare_request/5, prepare_request/6, prepare_retransmit/5, handle_answer/6, handle_answer/7, handle_error/6, handle_request/3]). %% diameter_{tcp,sctp} callbacks -export([message/3]). -include("diameter.hrl"). -include("diameter_gen_base_rfc3588.hrl"). -include("diameter_gen_base_accounting.hrl"). %% The listening transports use RFC 3588 dictionaries, the client %% transports use either 3588 or 6733. (So can't use the record %% definitions in the latter case.) %% =========================================================================== -define(util, diameter_util). -define(A, list_to_atom). -define(L, atom_to_list). %% Don't use is_record/2 since dictionary hrl's aren't included. %% (Since they define conflicting reqcords with the same names.) -define(is_record(Rec, Name), (Name == element(1, Rec))). -define(ADDR, {127,0,0,1}). -define(REALM, "erlang.org"). -define(HOST(Host, Realm), Host ++ [$.|Realm]). -define(EXTRA, an_extra_argument). %% Sequence mask for End-to-End and Hop-by-Hop identifiers. -define(CLIENT_MASK, {1,26}). %% 1 in top 6 bits %% How to construct messages, as record or list. -define(ENCODINGS, [list, record]). %% How to send answers, in a diameter_packet or not. -define(CONTAINERS, [pkt, msg]). %% 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, [false, true]). %% Which transport protocol to use. -define(TRANSPORTS, [tcp, sctp]). %% Send from a dedicated process? -define(SENDERS, [true, false]). %% Message callbacks from diameter_{tcp,sctp}? -define(CALLBACKS, [true, false]). -record(group, {transport, strings, client_service, client_encoding, client_dict0, client_sender, server_service, server_encoding, server_container, server_sender, server_throttle}). %% Not really what we should be setting unless the message is sent in %% the common application but diameter doesn't care. -define(APP_ID, ?DIAMETER_APP_ID_COMMON). %% An Application-ID the server doesn't support. -define(BAD_APP, 42). %% A common match when receiving answers in a client. -define(answer_message(SessionId, ResultCode), ['answer-message', {'Session-Id', SessionId}, {'Origin-Host', _}, {'Origin-Realm', _}, {'Result-Code', ResultCode} | _]). -define(answer_message(ResultCode), ?answer_message(_, ResultCode)). %% Config for diameter:start_service/2. -define(SERVICE(Name, Decode), [{'Origin-Host', Name ++ "." ++ ?REALM}, {'Origin-Realm', ?REALM}, {'Host-IP-Address', [?ADDR]}, {'Vendor-Id', 12345}, {'Product-Name', "OTP/diameter"}, {'Auth-Application-Id', [?DIAMETER_APP_ID_COMMON]}, {'Acct-Application-Id', [?DIAMETER_APP_ID_ACCOUNTING]}, {restrict_connections, false}, {string_decode, Decode}, {incoming_maxlen, 1 bsl 21}, {spawn_opt, [{min_heap_size, 5000}]} | [{application, [{dictionary, D}, {module, ?MODULE}, {answer_errors, callback}]} || D <- [diameter_gen_base_rfc3588, diameter_gen_base_accounting, diameter_gen_base_rfc6733, diameter_gen_acct_rfc6733]]]). -define(SUCCESS, ?'DIAMETER_BASE_RESULT-CODE_SUCCESS'). -define(COMMAND_UNSUPPORTED, ?'DIAMETER_BASE_RESULT-CODE_COMMAND_UNSUPPORTED'). -define(TOO_BUSY, ?'DIAMETER_BASE_RESULT-CODE_TOO_BUSY'). -define(APPLICATION_UNSUPPORTED, ?'DIAMETER_BASE_RESULT-CODE_APPLICATION_UNSUPPORTED'). -define(INVALID_HDR_BITS, ?'DIAMETER_BASE_RESULT-CODE_INVALID_HDR_BITS'). -define(INVALID_AVP_BITS, ?'DIAMETER_BASE_RESULT-CODE_INVALID_AVP_BITS'). -define(AVP_UNSUPPORTED, ?'DIAMETER_BASE_RESULT-CODE_AVP_UNSUPPORTED'). -define(UNSUPPORTED_VERSION, ?'DIAMETER_BASE_RESULT-CODE_UNSUPPORTED_VERSION'). -define(REALM_NOT_SERVED, ?'DIAMETER_BASE_RESULT-CODE_REALM_NOT_SERVED'). -define(UNABLE_TO_DELIVER, ?'DIAMETER_BASE_RESULT-CODE_UNABLE_TO_DELIVER'). -define(INVALID_AVP_LENGTH, ?'DIAMETER_BASE_RESULT-CODE_INVALID_AVP_LENGTH'). -define(EVENT_RECORD, ?'DIAMETER_BASE_ACCOUNTING-RECORD-TYPE_EVENT_RECORD'). -define(AUTHORIZE_ONLY, ?'DIAMETER_BASE_RE-AUTH-REQUEST-TYPE_AUTHORIZE_ONLY'). -define(AUTHORIZE_AUTHENTICATE, ?'DIAMETER_BASE_RE-AUTH-REQUEST-TYPE_AUTHORIZE_AUTHENTICATE'). -define(LOGOUT, ?'DIAMETER_BASE_TERMINATION-CAUSE_LOGOUT'). -define(BAD_ANSWER, ?'DIAMETER_BASE_TERMINATION-CAUSE_BAD_ANSWER'). -define(USER_MOVED, ?'DIAMETER_BASE_TERMINATION-CAUSE_USER_MOVED'). %% =========================================================================== suite() -> [{timetrap, {seconds, 10}}]. all() -> [start, result_codes, {group, traffic}, empty, stop]. groups() -> [{P, [P], Ts} || Ts <- [tc(tc())], P <- [shuffle, parallel]] ++ [{?util:name([T,R,D,A,C,S,SS,ST,CS]), [], [{group, if S -> shuffle; not S -> parallel end}]} || T <- ?TRANSPORTS, R <- ?ENCODINGS, D <- ?RFCS, A <- ?ENCODINGS, C <- ?CONTAINERS, S <- ?STRING_DECODES, SS <- ?SENDERS, ST <- ?CALLBACKS, CS <- ?SENDERS] ++ [{T, [], groups([[T,R,D,A,C,S,SS,ST,CS] || R <- ?ENCODINGS, D <- ?RFCS, A <- ?ENCODINGS, C <- ?CONTAINERS, S <- ?STRING_DECODES, SS <- ?SENDERS, ST <- ?CALLBACKS, CS <- ?SENDERS, SS orelse CS])} %% avoid deadlock || T <- ?TRANSPORTS] ++ [{traffic, [], [{group, T} || T <- ?TRANSPORTS]}]. %groups(_) -> %% debug % Name = [sctp,record,rfc6733,record,pkt,false,false,false,false], % [{group, ?util:name(Name)}]; groups(Names) -> [{group, ?util:name(L)} || L <- Names]. %tc([N|_]) -> %% debug % [N]; tc(L) -> L. %% -------------------- init_per_suite(Config) -> [{sctp, ?util:have_sctp()} | Config]. end_per_suite(_Config) -> ok. %% -------------------- init_per_group(Name, Config) when Name == shuffle; Name == parallel -> start_services(Config), add_transports(Config); init_per_group(sctp = Name, Config) -> {_, Sctp} = lists:keyfind(Name, 1, Config), if Sctp -> Config; true -> {skip, Name} end; init_per_group(Name, Config) -> case ?util:name(Name) of [T,R,D,A,C,S,SS,ST,CS] -> G = #group{transport = T, strings = S, client_service = [$C|?util:unique_string()], client_encoding = R, client_dict0 = dict0(D), client_sender = CS, server_service = [$S|?util:unique_string()], server_encoding = A, server_container = C, server_sender = SS, server_throttle = ST}, %% Limit the number of testcase, since the number of %% groups is large. All = ?util:scramble(tc()), TCs = lists:sublist(All, rand:uniform(32)), [{group, G}, {runlist, TCs} | Config]; _ -> Config end. end_per_group(Name, Config) when Name == shuffle; Name == parallel -> remove_transports(Config), stop_services(Config); end_per_group(_, _) -> ok. %% -------------------- %% Skip testcases that can reasonably fail under SCTP. init_per_testcase(Name, Config) -> TCs = proplists:get_value(runlist, Config, []), Run = [] == TCs orelse lists:member(Name, TCs), case [G || #group{transport = sctp} = G <- [proplists:get_value(group, Config)]] of [_] when Name == send_maxlen; Name == send_long -> {skip, sctp}; _ when not Run -> {skip, random}; _ -> [{testcase, Name} | Config] end. end_per_testcase(_, _) -> ok. %% -------------------- %% Testcases to run when services are started and connections %% established. tc() -> [send_ok, send_nok, send_eval, send_bad_answer, send_protocol_error, send_experimental_result, send_arbitrary, send_unknown, send_unknown_short, send_unknown_mandatory, send_unknown_short_mandatory, send_noreply, send_grouped_error, send_unsupported, send_unsupported_app, send_error_bit, send_unsupported_version, send_long_avp_length, send_short_avp_length, send_zero_avp_length, send_invalid_avp_length, send_invalid_reject, send_unexpected_mandatory_decode, send_unexpected_mandatory, send_long, send_maxlen, send_nopeer, send_noapp, send_discard, send_any_1, send_any_2, send_all_1, send_all_2, send_timeout, send_error, send_detach, send_encode_error, send_destination_1, send_destination_2, send_destination_3, send_destination_4, send_destination_5, send_destination_6, send_bad_option_1, send_bad_option_2, send_bad_filter_1, send_bad_filter_2, send_bad_filter_3, send_bad_filter_4, send_multiple_filters_1, send_multiple_filters_2, send_multiple_filters_3, send_anything]. %% =========================================================================== %% start/stop testcases start(_Config) -> ok = diameter:start(). start_services(Config) -> #group{strings = S, client_service = CN, server_service = SN} = group(Config), ok = diameter:start_service(SN, ?SERVICE(SN, S)), ok = diameter:start_service(CN, [{sequence, ?CLIENT_MASK} | ?SERVICE(CN, S)]). add_transports(Config) -> #group{transport = T, client_service = CN, client_sender = CS, server_service = SN, server_sender = SS, server_throttle = ST} = group(Config), LRef = ?util:listen(SN, [T, {sender, SS}, {message_cb, ST andalso {?MODULE, message, [4]}} | [{packet, hd(?util:scramble([false, raw]))} || T == sctp andalso CS]], [{capabilities_cb, fun capx/2}, {pool_size, 8}, {spawn_opt, [{min_heap_size, 8096}]}, {applications, apps(rfc3588)}]), Cs = [?util:connect(CN, [T, {sender, CS}], LRef, [{id, Id}, {capabilities, [{'Origin-State-Id', origin(Id)}]}, {applications, apps(D)}]) || A <- ?ENCODINGS, C <- ?CONTAINERS, D <- ?RFCS, Id <- [{A,C}]], %% The server uses the client's Origin-State-Id to decide how to %% answer. ?util:write_priv(Config, "transport", [LRef | Cs]). apps(D0) -> D = dict0(D0), [acct(D), D]. remove_transports(Config) -> #group{client_service = CN, server_service = SN} = group(Config), [LRef | Cs] = ?util:read_priv(Config, "transport"), try [] = [T || C <- Cs, T <- [?util:disconnect(CN, C, SN, LRef)], T /= ok] after ok = diameter:remove_transport(SN, LRef) end. 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) -> [] = ets:tab2list(diameter_request). stop(_Config) -> ok = diameter:stop(). capx(_, #diameter_caps{origin_host = {OH,DH}}) -> io:format("connection: ~p -> ~p~n", [DH,OH]), ok. %% =========================================================================== %% Ensure that result codes have the expected values. result_codes(_Config) -> {2001, 3001, 3002, 3003, 3004, 3007, 3008, 3009, 5001, 5011, 5014} = {?SUCCESS, ?COMMAND_UNSUPPORTED, ?UNABLE_TO_DELIVER, ?REALM_NOT_SERVED, ?TOO_BUSY, ?APPLICATION_UNSUPPORTED, ?INVALID_HDR_BITS, ?INVALID_AVP_BITS, ?AVP_UNSUPPORTED, ?UNSUPPORTED_VERSION, ?INVALID_AVP_LENGTH}. %% Send an ACR and expect success. send_ok(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 1}], ['ACA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, Req). %% Send an accounting ACR that the server answers badly to. send_nok(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 0}], ?answer_message(?INVALID_AVP_BITS) = call(Config, Req). %% Send an ACR and expect success. send_eval(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 3}], ['ACA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, Req). %% Send an accounting ACR that the server tries to answer with an %% inappropriate header. That the error is detected is coded in %% handle_answer. send_bad_answer(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 2}], ?answer_message(?SUCCESS) = call(Config, Req). %% Send an ACR that the server callback answers explicitly with a %% protocol error. send_protocol_error(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 4}], ?answer_message(?TOO_BUSY) = call(Config, Req). %% Send a 3xxx Experimental-Result in an answer not setting the E-bit %% and missing a Result-Code. send_experimental_result(Config) -> Req = ['ACR', {'Accounting-Record-Type', ?EVENT_RECORD}, {'Accounting-Record-Number', 5}], ['ACA', {'Session-Id', _} | _] = call(Config, Req). %% Send an ASR with an arbitrary non-mandatory AVP and expect success %% and the same AVP in the reply. send_arbitrary(Config) -> Req = ['ASR', {'AVP', [#diameter_avp{name = 'Product-Name', value = "XXX"}]}], ['ASA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | Avps] = call(Config, Req), {'AVP', [#diameter_avp{name = 'Product-Name', 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) -> Req = ['ASR', {'AVP', [#diameter_avp{code = 999, is_mandatory = false, data = <<17>>}]}], ['ASA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | Avps] = call(Config, Req), {'AVP', [#diameter_avp{code = 999, is_mandatory = false, data = <<17>>}]} = lists:last(Avps). %% Ditto, and point the AVP length past the end of the message. Expect %% 5014. send_unknown_short(Config) -> send_unknown_short(Config, false, ?INVALID_AVP_LENGTH). send_unknown_short(Config, M, RC) -> Req = ['ASR', {'AVP', [#diameter_avp{code = 999, is_mandatory = M, data = <<17>>}]}], ['ASA', {'Session-Id', _}, {'Result-Code', RC} | Avps] = call(Config, Req), [#'diameter_base_Failed-AVP'{'AVP' = As}] = proplists:get_value('Failed-AVP', Avps), [#diameter_avp{code = 999, is_mandatory = M, data = <<17, _/binary>>}] %% extra bits from padding = As. %% Ditto but set the M flag. send_unknown_mandatory(Config) -> Req = ['ASR', {'AVP', [#diameter_avp{code = 999, is_mandatory = true, data = <<17>>}]}], ['ASA', {'Session-Id', _}, {'Result-Code', ?AVP_UNSUPPORTED} | Avps] = call(Config, Req), [#'diameter_base_Failed-AVP'{'AVP' = As}] = proplists:get_value('Failed-AVP', Avps), [#diameter_avp{code = 999, is_mandatory = true, data = <<17>>}] = As. %% Ditto, and point the AVP length past the end of the message. Expect %% 5014 instead of 5001. send_unknown_short_mandatory(Config) -> send_unknown_short(Config, true, ?INVALID_AVP_LENGTH). %% Send an ASR containing an unexpected mandatory Session-Timeout. %% Expect 5001, and check that the value in Failed-AVP was decoded. send_unexpected_mandatory_decode(Config) -> Req = ['ASR', {'AVP', [#diameter_avp{code = 27, %% Session-Timeout is_mandatory = true, data = <<12:32>>}]}], ['ASA', {'Session-Id', _}, {'Result-Code', ?AVP_UNSUPPORTED} | Avps] = call(Config, Req), [#'diameter_base_Failed-AVP'{'AVP' = As}] = proplists:get_value('Failed-AVP', Avps), [#diameter_avp{code = 27, is_mandatory = true, value = 12, data = <<12:32>>}] = As. %% Send an containing a faulty Grouped AVP (empty Proxy-Host in %% Proxy-Info) and expect that only the faulty AVP is sent in %% Failed-AVP. The encoded values of Proxy-Host and Proxy-State are %% swapped in prepare_request since an empty Proxy-Host is an encode %% error. send_grouped_error(Config) -> Req = ['ASR', {'Proxy-Info', [[{'Proxy-Host', "abcd"}, {'Proxy-State', ""}]]}], ['ASA', {'Session-Id', _}, {'Result-Code', ?INVALID_AVP_LENGTH} | Avps] = call(Config, Req), [#'diameter_base_Failed-AVP'{'AVP' = As}] = proplists:get_value('Failed-AVP', Avps), [#diameter_avp{name = 'Proxy-Info', value = #'diameter_base_Proxy-Info' {'Proxy-Host' = Empty, 'Proxy-State' = undefined}}] = As, <<0>> = iolist_to_binary(Empty). %% Send an STR that the server ignores. send_noreply(Config) -> Req = ['STR', {'Termination-Cause', ?BAD_ANSWER}], {timeout, _} = call(Config, Req). %% Send an unsupported command and expect 3001. send_unsupported(Config) -> Req = ['STR', {'Termination-Cause', ?BAD_ANSWER}], ?answer_message(?COMMAND_UNSUPPORTED) = call(Config, Req). %% Send an unsupported application and expect 3007. send_unsupported_app(Config) -> Req = ['STR', {'Termination-Cause', ?BAD_ANSWER}], ?answer_message(?APPLICATION_UNSUPPORTED) = call(Config, Req). %% Send a request with the E bit set and expect 3008. send_error_bit(Config) -> Req = ['STR', {'Termination-Cause', ?BAD_ANSWER}], ?answer_message(?INVALID_HDR_BITS) = call(Config, Req). %% Send a bad version and check that we get 5011. send_unsupported_version(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], ['STA', {'Session-Id', _}, {'Result-Code', ?UNSUPPORTED_VERSION} | _] = call(Config, Req). %% Send a request containing an AVP length > data size. send_long_avp_length(Config) -> send_invalid_avp_length(Config). %% Send a request containing an AVP length < data size. send_short_avp_length(Config) -> send_invalid_avp_length(Config). %% Send a request containing an AVP whose advertised length is < 8. send_zero_avp_length(Config) -> send_invalid_avp_length(Config). %% Send a request containing an AVP length that doesn't match the %% AVP's type. send_invalid_avp_length(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], ['STA', {'Session-Id', _}, {'Result-Code', ?INVALID_AVP_LENGTH}, {'Origin-Host', _}, {'Origin-Realm', _}, {'User-Name', _}, {'Class', _}, {'Error-Message', _}, {'Error-Reporting-Host', _}, {'Failed-AVP', [#'diameter_base_Failed-AVP'{'AVP' = [_]}]} | _] = call(Config, Req). %% Send a request containing 5xxx errors that the server rejects with %% 3xxx. send_invalid_reject(Config) -> Req = ['STR', {'Termination-Cause', ?USER_MOVED}], ?answer_message(?TOO_BUSY) = call(Config, Req). %% Send an STR containing a known AVP, but one that's not expected and %% that sets the M-bit. send_unexpected_mandatory(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], ['STA', {'Session-Id', _}, {'Result-Code', ?AVP_UNSUPPORTED} | _] = call(Config, Req). %% Send something long that will be fragmented by TCP. send_long(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}, {'User-Name', [binary:copy(<<$X>>, 1 bsl 20)]}], ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, Req). %% Send something longer than the configure incoming_maxlen. send_maxlen(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}, {'User-Name', [binary:copy(<<$X>>, 1 bsl 21)]}], {timeout, _} = call(Config, Req). %% Send something for which pick_peer finds no suitable peer. send_nopeer(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], {error, no_connection} = call(Config, Req, [{extra, [?EXTRA]}]). %% Send something on an unconfigured application. send_noapp(Config) -> #group{client_service = CN} = group(Config), Req = ['STR', {'Termination-Cause', ?LOGOUT}], {error, no_connection} = diameter:call(CN, unknown_alias, Req). %% Send something that's discarded by prepare_request. send_discard(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], {error, unprepared} = call(Config, Req). %% Send with a disjunctive filter. 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(SN, "unknown.org")]}], ?answer_message(?UNABLE_TO_DELIVER) = call(Config, Req, [{filter, {first, [{all, [host, realm]}, realm]}}]). %% Send with a conjunctive filter. send_all_1(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], Realm = lists:foldr(fun(C,A) -> [C,A] end, [], ?REALM), ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = 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(SN, "unknown.org")]}], {error, no_connection} = call(Config, Req, [{filter, {all, [host, realm]}}]). %% Timeout before the server manages an answer. send_timeout(Config) -> Req = ['RAR', {'Re-Auth-Request-Type', ?AUTHORIZE_ONLY}], {timeout, _} = call(Config, Req, [{timeout, 1000}]). %% Explicitly answer with an answer-message and ensure that we %% received the Session-Id. send_error(Config) -> Req = ['RAR', {'Re-Auth-Request-Type', ?AUTHORIZE_AUTHENTICATE}], ?answer_message([_], ?TOO_BUSY) = call(Config, Req). %% Send a request with the detached option and receive it as a message %% from handle_answer instead. send_detach(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], Ref = make_ref(), ok = call(Config, Req, [{extra, [{self(), Ref}]}, detach]), Ans = receive {Ref, T} -> T end, ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = Ans. %% Send a request which can't be encoded and expect {error, encode}. send_encode_error(Config) -> {error, encode} = call(Config, ['STR']). %% No Termination-Cause %% Send with filtering and expect success. send_destination_1(Config) -> #group{server_service = SN} = group(Config), Req = ['STR', {'Termination-Cause', ?LOGOUT}, {'Destination-Host', [?HOST(SN, ?REALM)]}], ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, Req, [{filter, {all, [host, realm]}}]). send_destination_2(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, Req, [{filter, {all, [host, realm]}}]). %% Send with filtering on and expect failure when specifying an %% unknown host or realm. send_destination_3(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}, {'Destination-Realm', "unknown.org"}], {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(SN, "unknown.org")]}], {error, no_connection} = call(Config, Req, [{filter, {all, [host, realm]}}]). %% Send without filtering and expect an error answer when specifying %% an unknown host or realm. send_destination_5(Config) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}, {'Destination-Realm', "unknown.org"}], ?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(SN, "unknown.org")]}], ?answer_message(?UNABLE_TO_DELIVER) = call(Config, Req). %% Specify an invalid option and expect failure. send_bad_option_1(Config) -> send_bad_option(Config, x). send_bad_option_2(Config) -> send_bad_option(Config, {extra, false}). send_bad_option(Config, Opt) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], try call(Config, Req, [Opt]) of T -> erlang:error({?MODULE, ?LINE, T}) catch error: _ -> ok end. %% Specify an invalid filter and expect no matching peers. send_bad_filter_1(Config) -> send_bad_filter(Config, {all, none}). send_bad_filter_2(Config) -> send_bad_filter(Config, {host, x}). send_bad_filter_3(Config) -> send_bad_filter(Config, {eval, fun() -> true end}). send_bad_filter_4(Config) -> send_bad_filter(Config, {eval, {?MODULE, not_exported, []}}). send_bad_filter(Config, F) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], {error, no_connection} = call(Config, Req, [{filter, F}]). %% Specify multiple filter options and expect them be conjunctive. send_multiple_filters_1(Config) -> Fun = fun(#diameter_caps{}) -> true end, ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = send_multiple_filters(Config, [host, {eval, Fun}]). send_multiple_filters_2(Config) -> E = {erlang, is_tuple, []}, {error, no_connection} = send_multiple_filters(Config, [realm, {neg, {eval, E}}]). send_multiple_filters_3(Config) -> E1 = [fun(#diameter_caps{}, ok) -> true end, ok], E2 = {erlang, is_tuple, []}, E3 = {erlang, is_record, [diameter_caps]}, E4 = [{erlang, is_record, []}, diameter_caps], ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = send_multiple_filters(Config, [{eval, E} || E <- [E1,E2,E3,E4]]). send_multiple_filters(Config, Fs) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], call(Config, Req, [{filter, F} || F <- Fs]). %% Ensure that we can pass a request in any form to diameter:call/4, %% only the return value from the prepare_request callback being %% significant. send_anything(Config) -> ['STA', {'Session-Id', _}, {'Result-Code', ?SUCCESS} | _] = call(Config, anything). %% =========================================================================== group(Config) -> #group{} = proplists:get_value(group, Config). string(V, Config) -> #group{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_service = CN, client_encoding = ReqEncoding, client_dict0 = Dict0} = Group = group(Config), diameter:call(CN, dict(Req, Dict0), msg(Req, ReqEncoding, Dict0), [{extra, [{Name, Group}, diameter_lib:now()]} | Opts]). origin({A,C}) -> 2*codec(A) + container(C); origin(N) -> {codec(N band 2), container(N rem 2)}. %% Map booleans, but the readable atoms are part of (constructed) %% group names, so it's good that they're readable. codec(record) -> 0; codec(list) -> 1; codec(0) -> record; codec(_) -> list. container(pkt) -> 0; container(msg) -> 1; container(0) -> pkt; container(_) -> msg. msg([H|_] = Msg, record = E, diameter_gen_base_rfc3588) when H == 'ACR'; H == 'ACA' -> msg(Msg, E, diameter_gen_base_accounting); msg([H|_] = Msg, record = E, diameter_gen_base_rfc6733) when H == 'ACR'; H == 'ACA' -> msg(Msg, E, diameter_gen_acct_rfc6733); msg([H|T], record, Dict) -> Dict:'#new-'(Dict:msg2rec(H), T); msg(Msg, _, _) -> Msg. dict0(D) -> ?A("diameter_gen_base_" ++ ?L(D)). dict(Msg, Dict0) when 'ACR' == hd(Msg); 'ACA' == hd(Msg); ?is_record(Msg, diameter_base_accounting_ACR); ?is_record(Msg, diameter_base_accounting_ACA) -> acct(Dict0); dict(_, Dict0) -> Dict0. acct(diameter_gen_base_rfc3588) -> diameter_gen_base_accounting; acct(diameter_gen_base_rfc6733) -> diameter_gen_acct_rfc6733. %% Set only values that aren't already. set(_, [H|T], Vs) -> [H | Vs ++ T]; set(#group{client_dict0 = Dict0} = _Group, Rec, Vs) -> Dict = dict(Rec, Dict0), lists:foldl(fun({F,_} = FV, A) -> set(Dict, Dict:'#get-'(F, A), FV, A) end, Rec, Vs). set(Dict, E, FV, Rec) when E == undefined; E == [] -> Dict:'#set-'(FV, Rec); set(_, _, _, Rec) -> Rec. %% =========================================================================== %% diameter callbacks %% peer_up/3 peer_up(_SvcName, _Peer, State) -> State. %% peer_down/3 peer_down(_SvcName, _Peer, State) -> State. %% pick_peer/6-7 pick_peer(Peers, _, [$C|_], _State, {Name, Group}, _) when Name /= send_detach -> find(Group, Peers). pick_peer(_Peers, _, [$C|_], _State, {send_nopeer, _}, _, ?EXTRA) -> false; pick_peer(Peers, _, [$C|_], _State, {send_detach, Group}, _, {_,_}) -> find(Group, Peers). find(#group{client_service = CN, server_encoding = A, server_container = C}, [_|_] = Peers) -> Id = {A,C}, [P] = [P || P <- Peers, id(Id, P, CN)], {ok, P}. id(Id, {Pid, _Caps}, SvcName) -> [{ref, _}, {type, _}, {options, Opts} | _] = diameter:service_info(SvcName, Pid), lists:member({id, Id}, Opts). %% prepare_request/5-6 prepare_request(_Pkt, [$C|_], {_Ref, _Caps}, {send_discard, _}, _) -> {discard, unprepared}; prepare_request(Pkt, [$C|_], {_Ref, Caps}, {Name, Group}, _) -> {send, prepare(Pkt, Caps, Name, 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) when is_binary(Bin) -> io:format("~p: ~p~n", [T,P]). %% prepare/4 prepare(Pkt, Caps, N, #group{client_dict0 = Dict0} = Group) when N == send_unknown_short_mandatory; N == send_unknown_short -> Req = prepare(Pkt, Caps, Group), #diameter_packet{header = #diameter_header{length = L}, bin = Bin} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), %% Find the unknown AVP data at the end of the message and alter %% its length header. {Padding, [17|_]} = lists:splitwith(fun(C) -> C == 0 end, lists:reverse(binary_to_list(Bin))), Offset = L - length(Padding) - 4, <> = Bin, E#diameter_packet{bin = <>}; prepare(Pkt, Caps, N, #group{client_dict0 = Dict0} = Group) when N == send_long_avp_length; N == send_short_avp_length; N == send_zero_avp_length -> Req = prepare(Pkt, Caps, Group), %% Second last AVP in our STR is Auth-Application-Id of type %% Unsigned32: set AVP Length to a value other than 12 and place %% it last in the message (so as not to mess with Termination-Cause). #diameter_packet{header = #diameter_header{length = L}, bin = B} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), Offset = L - 24, %% to Auth-Application-Id <> = B, AL = case N of send_long_avp_length -> 13; send_short_avp_length -> 11; send_zero_avp_length -> 0 end, E#diameter_packet{bin = <>}; prepare(Pkt, Caps, N, #group{client_dict0 = Dict0} = Group) when N == send_invalid_avp_length; N == send_invalid_reject -> Req = prepare(Pkt, Caps, Group), %% Second last AVP in our STR is Auth-Application-Id of type %% Unsigned32: send data of length 8. #diameter_packet{header = #diameter_header{length = L}, bin = B0} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), Offset = L - 7 - 12, %% to AVP Length <> = B0, <> = H0, %% assert E#diameter_packet{bin = <>}; prepare(Pkt, Caps, send_unexpected_mandatory, #group{client_dict0 = Dict0} = Group) -> Req = prepare(Pkt, Caps, Group), #diameter_packet{bin = <>} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), {Code, Flags, undefined} = Dict0:avp_header('Proxy-State'), Avp = <>, E#diameter_packet{bin = <>}; prepare(Pkt, Caps, send_grouped_error, #group{client_dict0 = Dict0} = Group) -> Req = prepare(Pkt, Caps, Group), #diameter_packet{bin = Bin} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), {Code, Flags, undefined} = Dict0:avp_header('Proxy-Info'), %% Find Proxy-Info by looking for its header. Pattern = <>, {Offset, 8} = binary:match(Bin, Pattern), %% Extract and swap Proxy-Host/State payloads. <> = Bin, E#diameter_packet{bin = <>}; prepare(Pkt, Caps, send_unsupported, #group{client_dict0 = Dict0} = Group) -> Req = prepare(Pkt, Caps, Group), #diameter_packet{bin = <>} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), E#diameter_packet{bin = <>}; prepare(Pkt, Caps, send_unsupported_app, #group{client_dict0 = Dict0} = Group) -> Req = prepare(Pkt, Caps, Group), #diameter_packet{bin = <>} = E = diameter_codec:encode(Dict0, Pkt#diameter_packet{msg = Req}), E#diameter_packet{bin = <>}; prepare(Pkt, Caps, send_error_bit, Group) -> #diameter_packet{header = Hdr} = Pkt, Pkt#diameter_packet{header = Hdr#diameter_header{is_error = true}, msg = prepare(Pkt, Caps, Group)}; prepare(Pkt, Caps, send_unsupported_version, Group) -> #diameter_packet{header = Hdr} = Pkt, Pkt#diameter_packet{header = Hdr#diameter_header{version = 42}, msg = prepare(Pkt, Caps, Group)}; prepare(Pkt, Caps, send_anything, Group) -> Req = ['STR', {'Termination-Cause', ?LOGOUT}], prepare(Pkt#diameter_packet{msg = Req}, Caps, Group); prepare(Pkt, Caps, _Name, Group) -> prepare(Pkt, Caps, Group). %% prepare/3 prepare(#diameter_packet{msg = Req}, Caps, Group) when ?is_record(Req, diameter_base_accounting_ACR); 'ACR' == hd(Req) -> #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, DR}} = Caps, set(Group, Req, [{'Session-Id', diameter:session_id(OH)}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Destination-Realm', DR}]); prepare(#diameter_packet{msg = Req}, Caps, Group) when ?is_record(Req, diameter_base_ASR); 'ASR' == hd(Req) -> #diameter_caps{origin_host = {OH, DH}, origin_realm = {OR, DR}} = Caps, set(Group, Req, [{'Session-Id', diameter:session_id(OH)}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Destination-Host', DH}, {'Destination-Realm', DR}, {'Auth-Application-Id', ?APP_ID}]); prepare(#diameter_packet{msg = Req}, Caps, Group) when ?is_record(Req, diameter_base_STR); 'STR' == hd(Req) -> #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, DR}} = Caps, set(Group, Req, [{'Session-Id', diameter:session_id(OH)}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Destination-Realm', DR}, {'Auth-Application-Id', ?APP_ID}]); prepare(#diameter_packet{msg = Req}, Caps, Group) when ?is_record(Req, diameter_base_RAR); 'RAR' == hd(Req) -> #diameter_caps{origin_host = {OH, DH}, origin_realm = {OR, DR}} = Caps, set(Group, Req, [{'Session-Id', diameter:session_id(OH)}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Destination-Host', DH}, {'Destination-Realm', DR}, {'Auth-Application-Id', ?APP_ID}]). %% prepare_retransmit/5 prepare_retransmit(_Pkt, false, _Peer, _Name, _Group) -> discard. %% handle_answer/6-7 handle_answer(Pkt, Req, [$C|_], Peer, {Name, Group}, _) -> answer(Pkt, Req, Peer, Name, Group). handle_answer(Pkt, Req, [$C|_], Peer, {send_detach = Name, Group}, _, X) -> {Pid, Ref} = X, Pid ! {Ref, answer(Pkt, Req, Peer, Name, Group)}. answer(Pkt, Req, _Peer, Name, #group{client_dict0 = Dict0}) -> #diameter_packet{header = H, msg = Ans, errors = Es} = Pkt, ApplId = app(Req, Name, Dict0), #diameter_header{application_id = ApplId} = H, %% assert Dict = dict(Ans, Dict0), [R | Vs] = Dict:'#get-'(answer(Ans, Es, Name)), [Dict:rec2msg(R) | Vs]. %% Missing Result-Code and inappropriate Experimental-Result-Code. answer(Rec, Es, send_experimental_result) -> [{5004, #diameter_avp{name = 'Experimental-Result'}}, {5005, #diameter_avp{name = 'Result-Code'}}] = Es, Rec; %% An inappropriate E-bit results in a decode error ... answer(Rec, Es, send_bad_answer) -> [{5004, #diameter_avp{name = 'Result-Code'}} | _] = Es, Rec; %% ... while other errors are reflected in Failed-AVP. answer(Rec, [], _) -> Rec. app(_, send_unsupported_app, _) -> ?BAD_APP; app(Req, _, Dict0) -> Dict = dict(Req, Dict0), Dict:id(). %% handle_error/6 handle_error(timeout = Reason, _Req, [$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, [$C|_], _Peer, _, _Time) -> {error, Reason}. %% handle_request/3 %% 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, avps = As}, _, {_Ref, Caps}) -> #diameter_header{end_to_end_id = EI, hop_by_hop_id = HI} = H, {V,B} = ?CLIENT_MASK, V = EI bsr B, %% assert V = HI bsr B, %% #diameter_caps{origin_state_id = {_,[Id]}} = Caps, answer(origin(Id), request(M, [H|As], Caps)). answer(T, {Tag, Action, Post}) -> {Tag, answer(T, Action), Post}; answer(_, {reply, [#diameter_header{} | _]} = T) -> T; answer({A,C}, {reply, Ans}) -> answer(C, {reply, msg(Ans, A, diameter_gen_base_rfc3588)}); answer(pkt, {reply, Ans}) when not is_record(Ans, diameter_packet) -> {reply, #diameter_packet{msg = Ans}}; answer(_, T) -> T. %% request/3 %% send_experimental_result request(#diameter_base_accounting_ACR{'Accounting-Record-Number' = 5}, [Hdr | Avps], #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> [H,R|T] = [A || N <- ['Origin-Host', 'Origin-Realm', 'Session-Id', 'Accounting-Record-Type', 'Accounting-Record-Number'], #diameter_avp{} = A <- [lists:keyfind(N, #diameter_avp.name, Avps)]], Ans = [Hdr#diameter_header{is_request = false}, H#diameter_avp{data = OH}, R#diameter_avp{data = OR}, #diameter_avp{name = 'Experimental-Result', code = 297, need_encryption = false, data = [#diameter_avp{data = {?DIAMETER_DICT_COMMON, 'Vendor-Id', 123}}, #diameter_avp{data = {?DIAMETER_DICT_COMMON, 'Experimental-Result-Code', 3987}}]} | T], {reply, Ans}; request(Msg, _Avps, Caps) -> request(Msg, Caps). %% request/2 %% send_nok request(#diameter_base_accounting_ACR{'Accounting-Record-Number' = 0}, _) -> {eval_packet, {protocol_error, ?INVALID_AVP_BITS}, [fun log/2, invalid]}; %% send_bad_answer request(#diameter_base_accounting_ACR{'Session-Id' = SId, 'Accounting-Record-Type' = RT, 'Accounting-Record-Number' = 2 = RN}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> Ans = ['ACA', {'Result-Code', ?SUCCESS}, {'Session-Id', SId}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Accounting-Record-Type', RT}, {'Accounting-Record-Number', RN}], {reply, #diameter_packet{header = #diameter_header{is_error = true},%% NOT msg = Ans}}; %% send_eval request(#diameter_base_accounting_ACR{'Session-Id' = SId, 'Accounting-Record-Type' = RT, 'Accounting-Record-Number' = 3 = RN}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> Ans = ['ACA', {'Result-Code', ?SUCCESS}, {'Session-Id', SId}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Accounting-Record-Type', RT}, {'Accounting-Record-Number', RN}], {eval, {reply, Ans}, {erlang, now, []}}; %% send_ok request(#diameter_base_accounting_ACR{'Session-Id' = SId, 'Accounting-Record-Type' = RT, 'Accounting-Record-Number' = 1 = RN}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> {reply, ['ACA', {'Result-Code', ?SUCCESS}, {'Session-Id', SId}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'Accounting-Record-Type', RT}, {'Accounting-Record-Number', RN}]}; %% send_protocol_error request(#diameter_base_accounting_ACR{'Accounting-Record-Number' = 4}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> Ans = ['answer-message', {'Result-Code', ?TOO_BUSY}, {'Origin-Host', OH}, {'Origin-Realm', OR}], {reply, Ans}; request(#diameter_base_ASR{'Session-Id' = SId, 'AVP' = Avps}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> {reply, ['ASA', {'Result-Code', ?SUCCESS}, {'Session-Id', SId}, {'Origin-Host', OH}, {'Origin-Realm', OR}, {'AVP', Avps}]}; %% send_invalid_reject request(#diameter_base_STR{'Termination-Cause' = ?USER_MOVED}, _Caps) -> {protocol_error, ?TOO_BUSY}; %% send_noreply request(#diameter_base_STR{'Termination-Cause' = T}, _Caps) when T /= ?LOGOUT -> discard; %% send_destination_5 request(#diameter_base_STR{'Destination-Realm' = R}, #diameter_caps{origin_realm = {OR, _}}) when R /= undefined, R /= OR -> {protocol_error, ?REALM_NOT_SERVED}; %% send_destination_6 request(#diameter_base_STR{'Destination-Host' = [H]}, #diameter_caps{origin_host = {OH, _}}) when H /= OH -> {protocol_error, ?UNABLE_TO_DELIVER}; request(#diameter_base_STR{'Session-Id' = SId}, #diameter_caps{origin_host = {OH, _}, origin_realm = {OR, _}}) -> {reply, ['STA', {'Result-Code', ?SUCCESS}, {'Session-Id', SId}, {'Origin-Host', OH}, {'Origin-Realm', OR}]}; %% send_error/send_timeout request(#diameter_base_RAR{}, _Caps) -> receive after 2000 -> {protocol_error, ?TOO_BUSY} end. %% message/3 %% %% Limit the number of messages received. More can be received if read %% in the same packet. message(recv = D, {[_], Bin}, N) -> message(D, Bin, N); message(Dir, #diameter_packet{bin = Bin}, N) -> message(Dir, Bin, N); %% incoming request message(recv, <<_:32, 1, _/bits>> = Bin, N) -> [Bin, 1 < N, fun ?MODULE:message/3, N-1]; %% incoming answer message(recv, Bin, _) -> [Bin]; %% outgoing message(send, Bin, _) -> [Bin]; %% sent request message(ack, <<_:32, 1, _/bits>>, _) -> []; %% sent answer or discarded request message(ack, _, N) -> [0 =< N, fun ?MODULE:message/3, N+1].