diff options
Diffstat (limited to 'lib/ssl/src/dtls_connection.erl')
| -rw-r--r-- | lib/ssl/src/dtls_connection.erl | 215 |
1 files changed, 119 insertions, 96 deletions
diff --git a/lib/ssl/src/dtls_connection.erl b/lib/ssl/src/dtls_connection.erl index 070a90d481..440607e99d 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, @@ -53,7 +53,7 @@ %% Data handling -export([encode_data/3, passive_receive/2, next_record_if_active/1, handle_common_event/4, - send/3]). + send/3, socket/5]). %% gen_statem state functions -export([init/3, error/3, downgrade/3, %% Initiation and take down states @@ -77,20 +77,6 @@ start_fsm(Role, Host, Port, Socket, {#ssl_options{erl_dist = false},_, Tracker} catch error:{badmatch, {error, _} = Error} -> Error - end; - -start_fsm(Role, Host, Port, Socket, {#ssl_options{erl_dist = true},_, Tracker} = Opts, - User, {CbModule, _,_, _} = CbInfo, - Timeout) -> - try - {ok, Pid} = dtls_connection_sup:start_child_dist([Role, Host, Port, Socket, - Opts, User, CbInfo]), - {ok, SslSocket} = ssl_connection:socket_control(?MODULE, Socket, Pid, CbModule, Tracker), - ok = ssl_connection:handshake(SslSocket, Timeout), - {ok, SslSocket} - catch - error:{badmatch, {error, _} = Error} -> - Error end. send_handshake(Handshake, #state{connection_states = ConnectionStates} = States) -> @@ -201,6 +187,7 @@ 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, @@ -213,6 +200,9 @@ select_sni_extension(#client_hello{extensions = HelloExtensions}) -> select_sni_extension(_) -> undefined. +socket(Pid, Transport, Socket, Connection, _) -> + dtls_socket:socket(Pid, Transport, Socket, Connection). + %%==================================================================== %% tls_connection_sup API %%==================================================================== @@ -243,7 +233,7 @@ callback_mode() -> state_functions. %%-------------------------------------------------------------------- -%% State functionsconnection/2 +%% State functions %%-------------------------------------------------------------------- init({call, From}, {start, Timeout}, @@ -262,18 +252,25 @@ 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}, start_or_recv_from = From, - timer = Timer}, + timer = Timer, + 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 = {waiting, undefined, ?INITIAL_RETRANSMIT_TIMEOUT}}, - ?MODULE); + Result = ssl_connection:init(Type, Event, + State#state{flight_state = {retransmit, ?INITIAL_RETRANSMIT_TIMEOUT}, + protocol_specific = #{current_cookie_secret => dtls_v1:cookie_secret(), + previous_cookie_secret => <<>>}}, + ?MODULE), + erlang:send_after(dtls_v1:cookie_timeout(), self(), new_cookie_secret), + Result; + init({call, _} = Type, Event, #state{role = server} = State) -> %% I.E. DTLS over sctp ssl_connection:init(Type, Event, State#state{flight_state = reliable}, ?MODULE); @@ -296,26 +293,32 @@ error(_, _, _) -> hello(internal, #client_hello{cookie = <<>>, client_version = Version} = Hello, #state{role = server, transport_cb = Transport, - socket = Socket} = State0) -> - %% TODO: not hard code key + socket = Socket, + protocol_specific = #{current_cookie_secret := Secret}} = State0) -> {ok, {IP, Port}} = dtls_socket:peername(Transport, Socket), - Cookie = dtls_handshake:cookie(<<"secret">>, IP, Port, Hello), + 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) -> + socket = Socket, + protocol_specific = #{current_cookie_secret := Secret, + previous_cookie_secret := PSecret}} = State0) -> {ok, {IP, Port}} = dtls_socket:peername(Transport, Socket), - %% TODO: not hard code key - case dtls_handshake:cookie(<<"secret">>, IP, Port, Hello) of + case dtls_handshake:cookie(Secret, IP, Port, Hello) of Cookie -> handle_client_hello(Hello, State0); _ -> - %% Handle bad cookie as new cookie request RFC 6347 4.1.2 - hello(internal, Hello#client_hello{cookie = <<>>}, State0) + case dtls_handshake:cookie(PSecret, IP, Port, Hello) of + Cookie -> + handle_client_hello(Hello, State0); + _ -> + %% Handle bad cookie as new cookie request RFC 6347 4.1.2 + hello(internal, Hello#client_hello{cookie = <<>>}, State0) + end end; hello(internal, #hello_verify_request{cookie = Cookie}, #state{role = client, host = Host, port = Port, @@ -333,13 +336,13 @@ 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, @@ -356,13 +359,13 @@ 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). @@ -375,7 +378,11 @@ 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). @@ -383,6 +390,8 @@ 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). @@ -395,7 +404,11 @@ 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). @@ -409,12 +422,12 @@ 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 @@ -434,7 +447,6 @@ 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 @@ -442,16 +454,6 @@ downgrade(Type, Event, State) -> %%-------------------------------------------------------------------- %% raw data from socket, unpack records -handle_info({_,flight_retransmission_timeout}, connection, _) -> - {next_state, 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_timer, NextTimeout}}, - retransmit_epoch(StateName, State0)), - {Record, State} = next_record(State1), - next_event(StateName, Record, State); -handle_info({_, flight_retransmission_timeout}, _, _) -> - {next_state, keep_state_and_data}; handle_info({Protocol, _, _, _, Data}, StateName, #state{data_tag = Protocol} = State0) -> case next_dtls_record(Data, State0) of @@ -462,34 +464,52 @@ handle_info({Protocol, _, _, _, Data}, StateName, {stop, {shutdown, own_alert}} end; handle_info({CloseTag, Socket}, StateName, - #state{socket = Socket, close_tag = CloseTag, + #state{socket = Socket, + socket_options = #socket_options{active = Active}, + protocol_buffers = #protocol_buffers{dtls_cipher_texts = CTs}, + close_tag = CloseTag, negotiated_version = Version} = State) -> %% Note that as of DTLS 1.2 (TLS 1.1), %% failure to properly close a connection no longer requires that a %% session not be resumed. This is a change from DTLS 1.0 to conform %% with widespread implementation practice. - case Version of - {254, N} when N =< 253 -> - ok; - _ -> - %% As invalidate_sessions here causes performance issues, - %% we will conform to the widespread implementation - %% practice and go aginst the spec - %%invalidate_session(Role, Host, Port, Session) - ok - end, - ssl_connection:handle_normal_shutdown(?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), StateName, State), - {stop, {shutdown, transport_closed}}; + case (Active == false) andalso (CTs =/= []) of + false -> + case Version of + {254, N} when N =< 253 -> + ok; + _ -> + %% As invalidate_sessions here causes performance issues, + %% we will conform to the widespread implementation + %% practice and go aginst the spec + %%invalidate_session(Role, Host, Port, Session) + ok + end, + ssl_connection:handle_normal_shutdown(?ALERT_REC(?FATAL, ?CLOSE_NOTIFY), StateName, State), + {stop, {shutdown, transport_closed}}; + true -> + %% Fixes non-delivery of final DTLS record in {active, once}. + %% Basically allows the application the opportunity to set {active, once} again + %% and then receive the final message. + next_event(StateName, no_record, State) + end; + +handle_info(new_cookie_secret, StateName, + #state{protocol_specific = #{current_cookie_secret := Secret} = CookieInfo} = State) -> + erlang:send_after(dtls_v1:cookie_timeout(), self(), new_cookie_secret), + {next_state, StateName, State#state{protocol_specific = + CookieInfo#{current_cookie_secret => dtls_v1:cookie_secret(), + previous_cookie_secret => Secret}}}; handle_info(Msg, StateName, State) -> ssl_connection:handle_info(Msg, StateName, State). + handle_call(Event, From, StateName, State) -> ssl_connection:handle_call(Event, From, StateName, State, ?MODULE). 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}, @@ -498,19 +518,14 @@ handle_common_event(internal, #ssl_tls{type = ?HANDSHAKE, negotiated_version = Version} = State0) -> try case dtls_handshake:get_dtls_handshake(Version, Data, Buffers0) of - {more_data, Buffers} -> + {[], Buffers} -> {Record, State} = next_record(State0#state{protocol_buffers = Buffers}), next_event(StateName, Record, State); {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) @@ -534,6 +549,13 @@ 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) -> @@ -645,7 +667,8 @@ 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{ @@ -714,14 +737,14 @@ 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 @@ -772,17 +795,20 @@ next_flight(Flight) -> Flight#{handshakes => [], change_cipher_spec => undefined, handshakes_after_change_cipher_spec => []}. - start_flight(#state{transport_cb = gen_udp, - flight_state = {retransmit_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)}}; - + flight_state = {retransmit, Timeout}} = State) -> + start_retransmision_timer(Timeout, State); +start_flight(#state{transport_cb = gen_udp, + 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) -> + {State#state{flight_state = {retransmit, new_timeout(Timeout)}}, + [{state_timeout, Timeout, flight_retransmission_timeout}]}. new_timeout(N) when N =< 30 -> N * 2; @@ -806,13 +832,13 @@ 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; @@ -823,15 +849,11 @@ 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; @@ -846,3 +868,4 @@ unprocessed_events(Events) -> %% handshake events left to process before we should %% process more TLS-records received on the socket. erlang:length(Events)-1. + |