From 0d4047e02fe2275bdd8a8c940b3c79753e18cba2 Mon Sep 17 00:00:00 2001 From: Ingela Anderton Andin Date: Thu, 1 Jun 2017 23:34:51 +0200 Subject: dtls: Use enter actions Using enter actions for retransmission timers makes the code easier to understand. Previously the retransmission timer was incorrectly started in the connection state. Using enter actions feels like a cleaner approach than bloating the state with more flags. --- lib/ssl/src/dtls_connection.erl | 41 ++++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl index 2de947d8b4..b19f976cdb 100644 --- a/lib/ssl/src/dtls_connection.erl +++ b/lib/ssl/src/dtls_connection.erl @@ -115,7 +115,7 @@ send_handshake_flight(#state{socket = Socket, {Encoded, ConnectionStates} = encode_handshake_flight(lists:reverse(Flight), Version, 1400, Epoch, ConnectionStates0), send(Transport, Socket, Encoded), - start_flight(State0#state{connection_states = ConnectionStates}); + {State0#state{connection_states = ConnectionStates}, []}; send_handshake_flight(#state{socket = Socket, transport_cb = Transport, @@ -129,7 +129,7 @@ send_handshake_flight(#state{socket = Socket, {EncChangeCipher, ConnectionStates} = encode_change_cipher(ChangeCipher, Version, Epoch, ConnectionStates1), send(Transport, Socket, [HsBefore, EncChangeCipher]), - start_flight(State0#state{connection_states = ConnectionStates}); + {State0#state{connection_states = ConnectionStates}, []}; send_handshake_flight(#state{socket = Socket, transport_cb = Transport, @@ -145,7 +145,7 @@ send_handshake_flight(#state{socket = Socket, {HsAfter, ConnectionStates} = encode_handshake_flight(lists:reverse(Flight1), Version, 1400, Epoch, ConnectionStates2), send(Transport, Socket, [HsBefore, EncChangeCipher, HsAfter]), - start_flight(State0#state{connection_states = ConnectionStates}); + {State0#state{connection_states = ConnectionStates}, []}; send_handshake_flight(#state{socket = Socket, transport_cb = Transport, @@ -159,7 +159,7 @@ send_handshake_flight(#state{socket = Socket, {HsAfter, ConnectionStates} = encode_handshake_flight(lists:reverse(Flight1), Version, 1400, Epoch, ConnectionStates1), send(Transport, Socket, [EncChangeCipher, HsAfter]), - start_flight(State0#state{connection_states = ConnectionStates}). + {State0#state{connection_states = ConnectionStates}, []}. queue_change_cipher(ChangeCipher, #state{flight_buffer = Flight, connection_states = ConnectionStates0} = State) -> @@ -235,12 +235,14 @@ init([Role, Host, Port, Socket, Options, User, CbInfo]) -> end. callback_mode() -> - state_functions. + [state_functions, state_enter]. %%-------------------------------------------------------------------- %% State functions %%-------------------------------------------------------------------- +init(enter, _, State) -> + {keep_state, State}; init({call, From}, {start, Timeout}, #state{host = Host, port = Port, role = client, ssl_options = SslOpts, @@ -282,6 +284,8 @@ init({call, _} = Type, Event, #state{role = server} = State) -> init(Type, Event, State) -> ssl_connection:init(Type, Event, State, ?MODULE). +error(enter, _, State) -> + {keep_state, State}; error({call, From}, {start, _Timeout}, {Error, State}) -> {stop_and_reply, normal, {reply, From, {error, Error}}, State}; error({call, From}, Msg, State) -> @@ -295,6 +299,11 @@ error(_, _, _) -> #state{}) -> gen_statem:state_function_result(). %%-------------------------------------------------------------------- +hello(enter, _, #state{role = server} = State) -> + {keep_state, State}; +hello(enter, _, #state{role = client} = State0) -> + {State, Actions} = handle_flight_timer(State0), + {keep_state, State, Actions}; hello(internal, #client_hello{cookie = <<>>, client_version = Version} = Hello, #state{role = server, transport_cb = Transport, @@ -374,6 +383,9 @@ hello(state_timeout, Event, State) -> hello(Type, Event, State) -> ssl_connection:hello(Type, Event, State, ?MODULE). +abbreviated(enter, _, State0) -> + {State, Actions} = handle_flight_timer(State0), + {keep_state, State, Actions}; abbreviated(info, Event, State) -> handle_info(Event, abbreviated, State); abbreviated(internal = Type, @@ -391,6 +403,9 @@ abbreviated(state_timeout, Event, State) -> abbreviated(Type, Event, State) -> ssl_connection:abbreviated(Type, Event, State, ?MODULE). +certify(enter, _, State0) -> + {State, Actions} = handle_flight_timer(State0), + {keep_state, State, Actions}; certify(info, Event, State) -> handle_info(Event, certify, State); certify(internal = Type, #server_hello_done{} = Event, State) -> @@ -400,6 +415,9 @@ certify(state_timeout, Event, State) -> certify(Type, Event, State) -> ssl_connection:certify(Type, Event, State, ?MODULE). +cipher(enter, _, State0) -> + {State, Actions} = handle_flight_timer(State0), + {keep_state, State, Actions}; cipher(info, Event, State) -> handle_info(Event, cipher, State); cipher(internal = Type, #change_cipher_spec{type = <<1>>} = Event, @@ -417,6 +435,8 @@ cipher(state_timeout, Event, State) -> cipher(Type, Event, State) -> ssl_connection:cipher(Type, Event, State, ?MODULE). +connection(enter, _, State) -> + {keep_state, State}; connection(info, Event, State) -> handle_info(Event, connection, State); connection(internal, #hello_request{}, #state{host = Host, port = Port, @@ -449,6 +469,9 @@ connection(internal, #client_hello{}, #state{role = server, allow_renegotiate = connection(Type, Event, State) -> ssl_connection:connection(Type, Event, State, ?MODULE). +%%TODO does this make sense for DTLS ? +downgrade(enter, _, State) -> + {keep_state, State}; downgrade(Type, Event, State) -> ssl_connection:downgrade(Type, Event, State, ?MODULE). @@ -841,13 +864,13 @@ next_flight(Flight) -> change_cipher_spec => undefined, handshakes_after_change_cipher_spec => []}. -start_flight(#state{transport_cb = gen_udp, - flight_state = {retransmit, Timeout}} = State) -> +handle_flight_timer(#state{transport_cb = gen_udp, + flight_state = {retransmit, Timeout}} = State) -> start_retransmision_timer(Timeout, State); -start_flight(#state{transport_cb = gen_udp, +handle_flight_timer(#state{transport_cb = gen_udp, flight_state = connection} = State) -> {State, []}; -start_flight(State) -> +handle_flight_timer(State) -> %% No retransmision needed i.e DTLS over SCTP {State#state{flight_state = reliable}, []}. -- cgit v1.2.3 From e09b0cec251983eb838692ae3472a03ce42aea7a Mon Sep 17 00:00:00 2001 From: Ingela Anderton Andin Date: Mon, 5 Jun 2017 11:56:22 +0200 Subject: dtls: Fetch next DTLS record when dropping resent handshake data --- lib/ssl/src/dtls_connection.erl | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl index b19f976cdb..f338471829 100644 --- a/lib/ssl/src/dtls_connection.erl +++ b/lib/ssl/src/dtls_connection.erl @@ -773,14 +773,16 @@ next_event(connection = StateName, no_record, {#ssl_tls{epoch = Epoch, type = ?HANDSHAKE, version = _Version}, State1} = _Record when Epoch == CurrentEpoch-1 -> - {State, MoreActions} = send_handshake_flight(State1, CurrentEpoch), - {next_state, StateName, State, Actions ++ MoreActions}; + {State2, MoreActions} = send_handshake_flight(State1, CurrentEpoch), + {NextRecord, State} = next_record(State2), + next_event(StateName, NextRecord, State, Actions ++ MoreActions); %% From FLIGHT perspective CHANGE_CIPHER_SPEC is treated as a handshake {#ssl_tls{epoch = Epoch, type = ?CHANGE_CIPHER_SPEC, version = _Version}, State1} = _Record when Epoch == CurrentEpoch-1 -> - {State, MoreActions} = send_handshake_flight(State1, CurrentEpoch), - {next_state, StateName, State, Actions ++ MoreActions}; + {State2, MoreActions} = send_handshake_flight(State1, CurrentEpoch), + {NextRecord, State} = next_record(State2), + next_event(StateName, NextRecord, State, Actions ++ MoreActions); {#ssl_tls{epoch = _Epoch, version = _Version}, State1} -> %% TODO maybe buffer later epoch @@ -797,14 +799,16 @@ next_event(connection = StateName, Record, #ssl_tls{epoch = Epoch, type = ?HANDSHAKE, version = _Version} when Epoch == CurrentEpoch-1 -> - {State, MoreActions} = send_handshake_flight(State0, CurrentEpoch), - {next_state, StateName, State, Actions ++ MoreActions}; + {State1, MoreActions} = send_handshake_flight(State0, CurrentEpoch), + {NextRecord, State} = next_record(State1), + next_event(StateName, NextRecord, State, Actions ++ MoreActions); %% From FLIGHT perspective CHANGE_CIPHER_SPEC is treated as a handshake #ssl_tls{epoch = Epoch, type = ?CHANGE_CIPHER_SPEC, version = _Version} when Epoch == CurrentEpoch-1 -> - {State, MoreActions} = send_handshake_flight(State0, CurrentEpoch), - {next_state, StateName, State, Actions ++ MoreActions}; + {State1, MoreActions} = send_handshake_flight(State0, CurrentEpoch), + {NextRecord, State} = next_record(State1), + next_event(StateName, NextRecord, State, Actions ++ MoreActions); _ -> next_event(StateName, no_record, State0, Actions) end; -- cgit v1.2.3