diff options
Diffstat (limited to 'lib/ssl/src/dtls_connection.erl')
-rw-r--r-- | lib/ssl/src/dtls_connection.erl | 117 |
1 files changed, 97 insertions, 20 deletions
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl index f078b87bce..e8cfbbe2e3 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, @@ -302,7 +311,13 @@ hello(internal, #client_hello{cookie = <<>>, protocol_specific = #{current_cookie_secret := Secret}} = State0) -> {ok, {IP, Port}} = dtls_socket:peername(Transport, Socket), Cookie = dtls_handshake:cookie(Secret, IP, Port, Hello), - VerifyRequest = dtls_handshake:hello_verify_request(Cookie, Version), + %% FROM RFC 6347 regarding HelloVerifyRequest message: + %% The server_version field has the same syntax as in TLS. However, in + %% order to avoid the requirement to do version negotiation in the + %% initial handshake, DTLS 1.2 server implementations SHOULD use DTLS + %% version 1.0 regardless of the version of TLS that is expected to be + %% negotiated. + VerifyRequest = dtls_handshake:hello_verify_request(Cookie, ?HELLO_VERIFY_REQUEST_VERSION), State1 = prepare_flight(State0#state{negotiated_version = Version}), {State2, Actions} = send_handshake(VerifyRequest, State1), {Record, State} = next_record(State2), @@ -374,6 +389,9 @@ 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 +409,9 @@ 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 +421,9 @@ 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 +441,8 @@ 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 +475,9 @@ 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). @@ -695,7 +724,7 @@ next_record(#state{unprocessed_handshake_events = N} = State) when N > 0 -> next_record(#state{protocol_buffers = #protocol_buffers{dtls_cipher_texts = [#ssl_tls{epoch = Epoch} = CT | Rest]} = Buffers, - connection_states = ConnectionStates} = State) -> + connection_states = #{current_read := #{epoch := Epoch}} = ConnectionStates} = State) -> CurrentRead = dtls_record:get_connection_state_by_epoch(Epoch, ConnectionStates, read), case dtls_record:replay_detect(CT, CurrentRead) of false -> @@ -706,6 +735,23 @@ next_record(#state{protocol_buffers = Buffers#protocol_buffers{dtls_cipher_texts = Rest}, connection_states = ConnectionStates}) end; +next_record(#state{protocol_buffers = + #protocol_buffers{dtls_cipher_texts = [#ssl_tls{epoch = Epoch} | Rest]} + = Buffers, + connection_states = #{current_read := #{epoch := CurrentEpoch}} = ConnectionStates} = State) + when Epoch > CurrentEpoch -> + %% TODO Buffer later Epoch message, drop it for now + next_record(State#state{protocol_buffers = + Buffers#protocol_buffers{dtls_cipher_texts = Rest}, + connection_states = ConnectionStates}); +next_record(#state{protocol_buffers = + #protocol_buffers{dtls_cipher_texts = [ _ | Rest]} + = Buffers, + connection_states = ConnectionStates} = State) -> + %% Drop old epoch message + next_record(State#state{protocol_buffers = + Buffers#protocol_buffers{dtls_cipher_texts = Rest}, + connection_states = ConnectionStates}); next_record(#state{role = server, socket = {Listener, {Client, _}}, transport_cb = gen_udp} = State) -> @@ -750,31 +796,62 @@ 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, Epoch), - {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 -> + {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}, State} -> + version = _Version}, State1} -> %% TODO maybe buffer later epoch - {next_state, StateName, State, Actions}; + {Record, State} = next_record(State1), + next_event(StateName, Record, State, Actions); {#alert{} = Alert, State} -> {next_state, StateName, State, [{next_event, internal, Alert} | Actions]} end; +next_event(connection = StateName, Record, + #state{connection_states = #{current_read := #{epoch := CurrentEpoch}}} = State0, Actions) -> + case Record of + #ssl_tls{epoch = CurrentEpoch} -> + {next_state, StateName, State0, [{next_event, internal, {protocol_record, Record}} | Actions]}; + #ssl_tls{epoch = Epoch, + type = ?HANDSHAKE, + version = _Version} when Epoch == CurrentEpoch-1 -> + {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 -> + {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; next_event(StateName, Record, - #state{connection_states = #{current_read := #{epoch := CurrentEpoch}}} = State, Actions) -> + #state{connection_states = #{current_read := #{epoch := CurrentEpoch}}} = State0, Actions) -> case Record of no_record -> - {next_state, StateName, State, Actions}; + {next_state, StateName, State0, Actions}; #ssl_tls{epoch = CurrentEpoch, version = Version} = Record -> {next_state, StateName, - dtls_version(StateName, Version, State), + dtls_version(StateName, Version, State0), [{next_event, internal, {protocol_record, Record}} | Actions]}; #ssl_tls{epoch = _Epoch, version = _Version} = _Record -> %% TODO maybe buffer later epoch - {next_state, StateName, State, Actions}; + {Record, State} = next_record(State0), + next_event(StateName, Record, State, Actions); #alert{} = Alert -> - {next_state, StateName, State, [{next_event, internal, Alert} | Actions]} + {next_state, StateName, State0, [{next_event, internal, Alert} | Actions]} end. decode_cipher_text(#state{protocol_buffers = #protocol_buffers{dtls_cipher_texts = [ CT | Rest]} = Buffers, @@ -814,13 +891,13 @@ 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}, []}. |