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authorIngela Anderton Andin <[email protected]>2017-02-03 10:09:02 +0100
committerIngela Anderton Andin <[email protected]>2017-03-06 10:34:15 +0100
commit814a7666b9fee09e63c692cdffc0a3f3e6468c14 (patch)
tree467b11f61ce621408ac08cc2fb098d23d937df2f /lib
parentd8039bc64b57d21d91cc2399a0f7f8a13b628117 (diff)
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dtls: Hibernation and retransmit timers
Change retransmissions timers to use gen_statem state timeouts. We do not need a retransmission timer in the state connection as data traffic in DTLS over UDP is not retransmitted. If the last flight before transitioning into connection is lost, it will be resent when the peer resends its last flight. This will also make hibernation testing more straight forward. We need more adjustments later to handle a reliable DTLS transport such as SCTP.
Diffstat (limited to 'lib')
-rw-r--r--lib/ssl/src/dtls_connection.erl105
-rw-r--r--lib/ssl/src/ssl.app.src2
-rw-r--r--lib/ssl/src/ssl_connection.erl21
-rw-r--r--lib/ssl/src/tls_connection.erl8
-rw-r--r--lib/ssl/test/ssl_basic_SUITE.erl19
5 files changed, 76 insertions, 79 deletions
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl
index 40289f5e2f..513b4b5be0 100644
--- a/lib/ssl/src/dtls_connection.erl
+++ b/lib/ssl/src/dtls_connection.erl
@@ -39,7 +39,7 @@
-export([start_fsm/8, start_link/7, init/1]).
%% State transition handling
--export([next_record/1, next_event/3]).
+-export([next_record/1, next_event/3, next_event/4]).
%% Handshake handling
-export([renegotiate/2,
@@ -201,6 +201,7 @@ reinit_handshake_data(#state{protocol_buffers = Buffers} = State) ->
State#state{premaster_secret = undefined,
public_key_info = undefined,
tls_handshake_history = ssl_handshake:init_handshake_history(),
+ flight_state = {retransmit, ?INITIAL_RETRANSMIT_TIMEOUT},
protocol_buffers =
Buffers#protocol_buffers{
dtls_handshake_next_seq = 0,
@@ -246,7 +247,7 @@ callback_mode() ->
state_functions.
%%--------------------------------------------------------------------
-%% State functionsconnection/2
+%% State functions
%%--------------------------------------------------------------------
init({call, From}, {start, Timeout},
@@ -265,7 +266,7 @@ init({call, From}, {start, Timeout},
Version = Hello#client_hello.client_version,
HelloVersion = dtls_record:lowest_protocol_version(SslOpts#ssl_options.versions),
State1 = prepare_flight(State0#state{negotiated_version = Version}),
- State2 = send_handshake(Hello, State1#state{negotiated_version = HelloVersion}),
+ {State2, Actions} = send_handshake(Hello, State1#state{negotiated_version = HelloVersion}),
State3 = State2#state{negotiated_version = Version, %% Requested version
session =
Session0#session{session_id = Hello#client_hello.session_id},
@@ -274,7 +275,7 @@ init({call, From}, {start, Timeout},
flight_state = {retransmit, ?INITIAL_RETRANSMIT_TIMEOUT}
},
{Record, State} = next_record(State3),
- next_event(hello, Record, State);
+ next_event(hello, Record, State, Actions);
init({call, _} = Type, Event, #state{role = server, transport_cb = gen_udp} = State) ->
ssl_connection:init(Type, Event,
State#state{flight_state = {retransmit, ?INITIAL_RETRANSMIT_TIMEOUT}},
@@ -307,9 +308,9 @@ hello(internal, #client_hello{cookie = <<>>,
Cookie = dtls_handshake:cookie(<<"secret">>, IP, Port, Hello),
VerifyRequest = dtls_handshake:hello_verify_request(Cookie, Version),
State1 = prepare_flight(State0#state{negotiated_version = Version}),
- State2 = send_handshake(VerifyRequest, State1),
+ {State2, Actions} = send_handshake(VerifyRequest, State1),
{Record, State} = next_record(State2),
- next_event(hello, Record, State#state{tls_handshake_history = ssl_handshake:init_handshake_history()});
+ next_event(hello, Record, State#state{tls_handshake_history = ssl_handshake:init_handshake_history()}, Actions);
hello(internal, #client_hello{cookie = Cookie} = Hello, #state{role = server,
transport_cb = Transport,
socket = Socket} = State0) ->
@@ -338,13 +339,13 @@ hello(internal, #hello_verify_request{cookie = Cookie}, #state{role = client,
Cache, CacheCb, Renegotiation, OwnCert),
Version = Hello#client_hello.client_version,
HelloVersion = dtls_record:lowest_protocol_version(SslOpts#ssl_options.versions),
- State2 = send_handshake(Hello, State1#state{negotiated_version = HelloVersion}),
+ {State2, Actions} = send_handshake(Hello, State1#state{negotiated_version = HelloVersion}),
State3 = State2#state{negotiated_version = Version, %% Requested version
session =
Session0#session{session_id =
Hello#client_hello.session_id}},
{Record, State} = next_record(State3),
- next_event(hello, Record, State);
+ next_event(hello, Record, State, Actions);
hello(internal, #server_hello{} = Hello,
#state{connection_states = ConnectionStates0,
negotiated_version = ReqVersion,
@@ -361,13 +362,13 @@ hello(internal, #server_hello{} = Hello,
hello(internal, {handshake, {#client_hello{cookie = <<>>} = Handshake, _}}, State) ->
%% Initial hello should not be in handshake history
{next_state, hello, State, [{next_event, internal, Handshake}]};
-
hello(internal, {handshake, {#hello_verify_request{} = Handshake, _}}, State) ->
%% hello_verify should not be in handshake history
{next_state, hello, State, [{next_event, internal, Handshake}]};
-
hello(info, Event, State) ->
handle_info(Event, hello, State);
+hello(state_timeout, Event, State) ->
+ handle_state_timeout(Event, hello, State);
hello(Type, Event, State) ->
ssl_connection:hello(Type, Event, State, ?MODULE).
@@ -380,7 +381,11 @@ abbreviated(internal = Type,
ConnectionStates = dtls_record:next_epoch(ConnectionStates1, read),
ssl_connection:abbreviated(Type, Event, State#state{connection_states = ConnectionStates}, ?MODULE);
abbreviated(internal = Type, #finished{} = Event, #state{connection_states = ConnectionStates} = State) ->
- ssl_connection:cipher(Type, Event, prepare_flight(State#state{connection_states = ConnectionStates}), ?MODULE);
+ ssl_connection:abbreviated(Type, Event,
+ prepare_flight(State#state{connection_states = ConnectionStates,
+ flight_state = connection}), ?MODULE);
+abbreviated(state_timeout, Event, State) ->
+ handle_state_timeout(Event, abbreviated, State);
abbreviated(Type, Event, State) ->
ssl_connection:abbreviated(Type, Event, State, ?MODULE).
@@ -388,6 +393,8 @@ certify(info, Event, State) ->
handle_info(Event, certify, State);
certify(internal = Type, #server_hello_done{} = Event, State) ->
ssl_connection:certify(Type, Event, prepare_flight(State), ?MODULE);
+certify(state_timeout, Event, State) ->
+ handle_state_timeout(Event, certify, State);
certify(Type, Event, State) ->
ssl_connection:certify(Type, Event, State, ?MODULE).
@@ -400,7 +407,11 @@ cipher(internal = Type, #change_cipher_spec{type = <<1>>} = Event,
ssl_connection:cipher(Type, Event, State#state{connection_states = ConnectionStates}, ?MODULE);
cipher(internal = Type, #finished{} = Event, #state{connection_states = ConnectionStates} = State) ->
ssl_connection:cipher(Type, Event,
- prepare_flight(State#state{connection_states = ConnectionStates}), ?MODULE);
+ prepare_flight(State#state{connection_states = ConnectionStates,
+ flight_state = connection}),
+ ?MODULE);
+cipher(state_timeout, Event, State) ->
+ handle_state_timeout(Event, cipher, State);
cipher(Type, Event, State) ->
ssl_connection:cipher(Type, Event, State, ?MODULE).
@@ -414,12 +425,12 @@ connection(internal, #hello_request{}, #state{host = Host, port = Port,
renegotiation = {Renegotiation, _}} = State0) ->
Hello = dtls_handshake:client_hello(Host, Port, ConnectionStates0, SslOpts,
Cache, CacheCb, Renegotiation, Cert),
- State1 = send_handshake(Hello, State0),
+ {State1, Actions} = send_handshake(Hello, State0),
{Record, State} =
next_record(
State1#state{session = Session0#session{session_id
= Hello#client_hello.session_id}}),
- next_event(hello, Record, State);
+ next_event(hello, Record, State, Actions);
connection(internal, #client_hello{} = Hello, #state{role = server, allow_renegotiate = true} = State) ->
%% Mitigate Computational DoS attack
%% http://www.educatedguesswork.org/2011/10/ssltls_and_computational_dos.html
@@ -439,7 +450,6 @@ connection(Type, Event, State) ->
downgrade(Type, Event, State) ->
ssl_connection:downgrade(Type, Event, State, ?MODULE).
-
%%--------------------------------------------------------------------
%% Description: This function is called by a gen_fsm when it receives any
%% other message than a synchronous or asynchronous event
@@ -447,16 +457,6 @@ downgrade(Type, Event, State) ->
%%--------------------------------------------------------------------
%% raw data from socket, unpack records
-handle_info({_,flight_retransmission_timeout}, connection, _) ->
- {keep_state_and_data, []};
-handle_info({Ref, flight_retransmission_timeout}, StateName,
- #state{flight_state = {waiting, Ref, NextTimeout}} = State0) ->
- State1 = send_handshake_flight(State0#state{flight_state = {retransmit, NextTimeout}},
- retransmit_epoch(StateName, State0)),
- {Record, State} = next_record(State1),
- next_event(StateName, Record, State);
-handle_info({_, flight_retransmission_timeout}, _, _) ->
- {keep_state_and_data, []};
handle_info({Protocol, _, _, _, Data}, StateName,
#state{data_tag = Protocol} = State0) ->
case next_dtls_record(Data, State0) of
@@ -494,7 +494,6 @@ handle_call(Event, From, StateName, State) ->
handle_common_event(internal, #alert{} = Alert, StateName,
#state{negotiated_version = Version} = State) ->
ssl_connection:handle_own_alert(Alert, Version, StateName, State);
-
%%% DTLS record protocol level handshake messages
handle_common_event(internal, #ssl_tls{type = ?HANDSHAKE,
fragment = Data},
@@ -509,13 +508,8 @@ handle_common_event(internal, #ssl_tls{type = ?HANDSHAKE,
{Packets, Buffers} ->
State = State0#state{protocol_buffers = Buffers},
Events = dtls_handshake_events(Packets),
- case StateName of
- connection ->
- ssl_connection:hibernate_after(StateName, State, Events);
- _ ->
- {next_state, StateName,
- State#state{unprocessed_handshake_events = unprocessed_events(Events)}, Events}
- end
+ {next_state, StateName,
+ State#state{unprocessed_handshake_events = unprocessed_events(Events)}, Events}
end
catch throw:#alert{} = Alert ->
ssl_connection:handle_own_alert(Alert, Version, StateName, State0)
@@ -539,6 +533,13 @@ handle_common_event(internal, #ssl_tls{type = ?ALERT, fragment = EncAlerts}, Sta
handle_common_event(internal, #ssl_tls{type = _Unknown}, StateName, State) ->
{next_state, StateName, State}.
+handle_state_timeout(flight_retransmission_timeout, StateName,
+ #state{flight_state = {retransmit, NextTimeout}} = State0) ->
+ {State1, Actions} = send_handshake_flight(State0#state{flight_state = {retransmit, NextTimeout}},
+ retransmit_epoch(StateName, State0)),
+ {Record, State} = next_record(State1),
+ next_event(StateName, Record, State, Actions).
+
send(Transport, {_, {{_,_}, _} = Socket}, Data) ->
send(Transport, Socket, Data);
send(Transport, Socket, Data) ->
@@ -650,7 +651,8 @@ initial_state(Role, Host, Port, Socket, {SSLOptions, SocketOptions, _}, User,
allow_renegotiate = SSLOptions#ssl_options.client_renegotiation,
start_or_recv_from = undefined,
protocol_cb = ?MODULE,
- flight_buffer = new_flight()
+ flight_buffer = new_flight(),
+ flight_state = {retransmit, ?INITIAL_RETRANSMIT_TIMEOUT}
}.
next_dtls_record(Data, #state{protocol_buffers = #protocol_buffers{
@@ -719,14 +721,14 @@ next_event(connection = StateName, no_record,
#state{connection_states = #{current_read := #{epoch := CurrentEpoch}}} = State0, Actions) ->
case next_record_if_active(State0) of
{no_record, State} ->
- ssl_connection:hibernate_after(StateName, State, Actions);
+ ssl_connection:hibernate_after(StateName, State, Actions);
{#ssl_tls{epoch = CurrentEpoch} = Record, State} ->
{next_state, StateName, State, [{next_event, internal, {protocol_record, Record}} | Actions]};
{#ssl_tls{epoch = Epoch,
type = ?HANDSHAKE,
version = _Version}, State1} = _Record when Epoch == CurrentEpoch-1 ->
- State = send_handshake_flight(State1, Epoch),
- {next_state, StateName, State, Actions};
+ {State, MoreActions} = send_handshake_flight(State1, Epoch),
+ {next_state, StateName, State, Actions ++ MoreActions};
{#ssl_tls{epoch = _Epoch,
version = _Version}, State} ->
%% TODO maybe buffer later epoch
@@ -782,16 +784,15 @@ start_flight(#state{transport_cb = gen_udp,
flight_state = {retransmit, Timeout}} = State) ->
start_retransmision_timer(Timeout, State);
start_flight(#state{transport_cb = gen_udp,
- flight_state = {waiting, _, Timeout}} = State) ->
- start_retransmision_timer(Timeout, State);
+ flight_state = connection} = State) ->
+ {State, []};
start_flight(State) ->
%% No retransmision needed i.e DTLS over SCTP
- State#state{flight_state = reliable}.
+ {State#state{flight_state = reliable}, []}.
start_retransmision_timer(Timeout, State) ->
- Ref = erlang:make_ref(),
- _ = erlang:send_after(Timeout, self(), {Ref, flight_retransmission_timeout}),
- State#state{flight_state = {waiting, Ref, new_timeout(Timeout)}}.
+ {State#state{flight_state = {retransmit, new_timeout(Timeout)}},
+ [{state_timeout, Timeout, flight_retransmission_timeout}]}.
new_timeout(N) when N =< 30 ->
N * 2;
@@ -815,13 +816,13 @@ renegotiate(#state{role = server,
connection_states = CS0} = State0, Actions) ->
HelloRequest = ssl_handshake:hello_request(),
CS = CS0#{write_msg_seq => 0},
- State1 = send_handshake(HelloRequest,
- State0#state{connection_states =
- CS}),
+ {State1, MoreActions} = send_handshake(HelloRequest,
+ State0#state{connection_states =
+ CS}),
Hs0 = ssl_handshake:init_handshake_history(),
{Record, State} = next_record(State1#state{tls_handshake_history = Hs0,
protocol_buffers = #protocol_buffers{}}),
- next_event(hello, Record, State, Actions).
+ next_event(hello, Record, State, Actions ++ MoreActions).
handle_alerts([], Result) ->
Result;
@@ -832,15 +833,11 @@ handle_alerts([Alert | Alerts], {next_state, StateName, State}) ->
handle_alerts([Alert | Alerts], {next_state, StateName, State, _Actions}) ->
handle_alerts(Alerts, ssl_connection:handle_alert(Alert, StateName, State)).
-retransmit_epoch(StateName, #state{connection_states = ConnectionStates}) ->
+retransmit_epoch(_StateName, #state{connection_states = ConnectionStates}) ->
#{epoch := Epoch} =
ssl_record:current_connection_state(ConnectionStates, write),
- case StateName of
- connection ->
- Epoch-1;
- _ ->
- Epoch
- end.
+ Epoch.
+
update_handshake_history(#hello_verify_request{}, _, Hist) ->
Hist;
diff --git a/lib/ssl/src/ssl.app.src b/lib/ssl/src/ssl.app.src
index 148989174d..064dcd6892 100644
--- a/lib/ssl/src/ssl.app.src
+++ b/lib/ssl/src/ssl.app.src
@@ -63,7 +63,7 @@
{applications, [crypto, public_key, kernel, stdlib]},
{env, []},
{mod, {ssl_app, []}},
- {runtime_dependencies, ["stdlib-3.1","public_key-1.2","kernel-3.0",
+ {runtime_dependencies, ["stdlib-3.2","public_key-1.2","kernel-3.0",
"erts-7.0","crypto-3.3", "inets-5.10.7"]}]}.
diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl
index 20447fa4fe..5244db31af 100644
--- a/lib/ssl/src/ssl_connection.erl
+++ b/lib/ssl/src/ssl_connection.erl
@@ -434,11 +434,11 @@ abbreviated(internal, #finished{verify_data = Data} = Finished,
verified ->
ConnectionStates1 =
ssl_record:set_server_verify_data(current_read, Data, ConnectionStates0),
- State1 =
+ {State1, Actions} =
finalize_handshake(State0#state{connection_states = ConnectionStates1},
abbreviated, Connection),
{Record, State} = prepare_connection(State1#state{expecting_finished = false}, Connection),
- Connection:next_event(connection, Record, State);
+ Connection:next_event(connection, Record, State, Actions);
#alert{} = Alert ->
handle_own_alert(Alert, Version, abbreviated, State0)
end;
@@ -858,6 +858,7 @@ handle_common_event(internal, #change_cipher_spec{type = <<1>>}, StateName,
StateName, State);
handle_common_event(_Type, Msg, StateName, #state{negotiated_version = Version} = State,
_) ->
+ ct:pal("Unexpected msg ~p", [Msg]),
Alert = ?ALERT_REC(?FATAL,?UNEXPECTED_MESSAGE),
handle_own_alert(Alert, Version, {StateName, Msg}, State).
@@ -1238,13 +1239,13 @@ new_server_hello(#server_hello{cipher_suite = CipherSuite,
negotiated_version = Version} = State0, Connection) ->
try server_certify_and_key_exchange(State0, Connection) of
#state{} = State1 ->
- State2 = server_hello_done(State1, Connection),
+ {State2, Actions} = server_hello_done(State1, Connection),
Session =
Session0#session{session_id = SessionId,
cipher_suite = CipherSuite,
compression_method = Compression},
{Record, State} = Connection:next_record(State2#state{session = Session}),
- Connection:next_event(certify, Record, State)
+ Connection:next_event(certify, Record, State, Actions)
catch
#alert{} = Alert ->
handle_own_alert(Alert, Version, hello, State0)
@@ -1259,10 +1260,10 @@ resumed_server_hello(#state{session = Session,
{_, ConnectionStates1} ->
State1 = State0#state{connection_states = ConnectionStates1,
session = Session},
- State2 =
+ {State2, Actions} =
finalize_handshake(State1, abbreviated, Connection),
{Record, State} = Connection:next_record(State2),
- Connection:next_event(abbreviated, Record, State);
+ Connection:next_event(abbreviated, Record, State, Actions);
#alert{} = Alert ->
handle_own_alert(Alert, Version, hello, State0)
end.
@@ -1345,12 +1346,12 @@ client_certify_and_key_exchange(#state{negotiated_version = Version} =
State0, Connection) ->
try do_client_certify_and_key_exchange(State0, Connection) of
State1 = #state{} ->
- State2 = finalize_handshake(State1, certify, Connection),
+ {State2, Actions} = finalize_handshake(State1, certify, Connection),
State3 = State2#state{
%% Reinitialize
client_certificate_requested = false},
{Record, State} = Connection:next_record(State3),
- Connection:next_event(cipher, Record, State)
+ Connection:next_event(cipher, Record, State, Actions)
catch
throw:#alert{} = Alert ->
handle_own_alert(Alert, Version, certify, State0)
@@ -1872,11 +1873,11 @@ cipher_role(server, Data, Session, #state{connection_states = ConnectionStates0
Connection) ->
ConnectionStates1 = ssl_record:set_client_verify_data(current_read, Data,
ConnectionStates0),
- State1 =
+ {State1, Actions} =
finalize_handshake(State0#state{connection_states = ConnectionStates1,
session = Session}, cipher, Connection),
{Record, State} = prepare_connection(State1, Connection),
- Connection:next_event(connection, Record, State).
+ Connection:next_event(connection, Record, State, Actions).
is_anonymous(Algo) when Algo == dh_anon;
Algo == ecdh_anon;
diff --git a/lib/ssl/src/tls_connection.erl b/lib/ssl/src/tls_connection.erl
index 97a611afd9..c6e530e164 100644
--- a/lib/ssl/src/tls_connection.erl
+++ b/lib/ssl/src/tls_connection.erl
@@ -48,7 +48,7 @@
-export([encode_data/3, encode_alert/3]).
%% State transition handling
--export([next_record/1, next_event/3]).
+-export([next_record/1, next_event/3, next_event/4]).
%% Handshake handling
-export([renegotiate/2, send_handshake/2,
@@ -118,7 +118,7 @@ send_handshake_flight(#state{socket = Socket,
transport_cb = Transport,
flight_buffer = Flight} = State0) ->
send(Transport, Socket, Flight),
- State0#state{flight_buffer = []}.
+ {State0#state{flight_buffer = []}, []}.
queue_change_cipher(Msg, #state{negotiated_version = Version,
flight_buffer = Flight0,
@@ -345,12 +345,12 @@ connection(internal, #hello_request{},
renegotiation = {Renegotiation, _}} = State0) ->
Hello = tls_handshake:client_hello(Host, Port, ConnectionStates0, SslOpts,
Cache, CacheCb, Renegotiation, Cert),
- State1 = send_handshake(Hello, State0),
+ {State1, Actions} = send_handshake(Hello, State0),
{Record, State} =
next_record(
State1#state{session = Session0#session{session_id
= Hello#client_hello.session_id}}),
- next_event(hello, Record, State);
+ next_event(hello, Record, State, Actions);
connection(internal, #client_hello{} = Hello,
#state{role = server, allow_renegotiate = true} = State0) ->
%% Mitigate Computational DoS attack
diff --git a/lib/ssl/test/ssl_basic_SUITE.erl b/lib/ssl/test/ssl_basic_SUITE.erl
index 27adcc115c..6515b6234b 100644
--- a/lib/ssl/test/ssl_basic_SUITE.erl
+++ b/lib/ssl/test/ssl_basic_SUITE.erl
@@ -83,13 +83,13 @@ groups() ->
].
tls_versions_groups ()->
- [{group, api_tls},
+ [{group, renegotiate}, %% Should be in all_versions_groups not fixed for DTLS yet
+ {group, api_tls},
{group, tls_ciphers},
{group, error_handling_tests_tls}].
all_versions_groups ()->
[{group, api},
- %%{group, renegotiate},
{group, ciphers},
{group, ciphers_ec},
{group, error_handling_tests}].
@@ -3336,11 +3336,11 @@ hibernate(Config) ->
process_info(Pid, current_function),
ssl_test_lib:check_result(Server, ok, Client, ok),
+
timer:sleep(1500),
-
{current_function, {erlang, hibernate, 3}} =
process_info(Pid, current_function),
-
+
ssl_test_lib:close(Server),
ssl_test_lib:close(Client).
@@ -3373,13 +3373,12 @@ hibernate_right_away(Config) ->
[{port, Port1}, {options, [{hibernate_after, 0}|ClientOpts]}]),
ssl_test_lib:check_result(Server1, ok, Client1, ok),
-
- {current_function, {erlang, hibernate, 3}} =
+
+ {current_function, {erlang, hibernate, 3}} =
process_info(Pid1, current_function),
-
ssl_test_lib:close(Server1),
ssl_test_lib:close(Client1),
-
+
Server2 = ssl_test_lib:start_server(StartServerOpts),
Port2 = ssl_test_lib:inet_port(Server2),
{Client2, #sslsocket{pid = Pid2}} = ssl_test_lib:start_client(StartClientOpts ++
@@ -3387,8 +3386,8 @@ hibernate_right_away(Config) ->
ssl_test_lib:check_result(Server2, ok, Client2, ok),
- timer:sleep(1000), %% Schedule out
-
+ ct:sleep(1000), %% Schedule out
+
{current_function, {erlang, hibernate, 3}} =
process_info(Pid2, current_function),