From 5096bb6c39d133e51d4f96c74d9e93d546fe3773 Mon Sep 17 00:00:00 2001 From: Ingela Anderton Andin Date: Thu, 20 Dec 2018 22:30:22 +0100 Subject: ssl: Clean up extension handling Use throw stratgy for erro handling in extension handling. Makes code consistent and easier to refactor. Also fixes bug that an incorrect return value for gen_statem could be created when alert was a result of handling renegotiation info extension. --- lib/ssl/src/dtls_handshake.erl | 15 +++---- lib/ssl/src/ssl_handshake.erl | 96 ++++++++++++++++++------------------------ lib/ssl/src/tls_handshake.erl | 10 ++--- 3 files changed, 52 insertions(+), 69 deletions(-) (limited to 'lib') diff --git a/lib/ssl/src/dtls_handshake.erl b/lib/ssl/src/dtls_handshake.erl index 3f70eaec8a..1917d51c03 100644 --- a/lib/ssl/src/dtls_handshake.erl +++ b/lib/ssl/src/dtls_handshake.erl @@ -215,8 +215,6 @@ handle_client_hello_extensions(Version, Type, Random, CipherSuites, HelloExt, dtls_v1:corresponding_tls_version(Version), SslOpts, Session0, ConnectionStates0, Renegotiation) of - #alert{} = Alert -> - Alert; {Session, ConnectionStates, Protocol, ServerHelloExt} -> {Version, {Type, Session}, ConnectionStates, Protocol, ServerHelloExt, HashSign} catch throw:Alert -> @@ -225,17 +223,16 @@ handle_client_hello_extensions(Version, Type, Random, CipherSuites, handle_server_hello_extensions(Version, SessionId, Random, CipherSuite, Compression, HelloExt, SslOpt, ConnectionStates0, Renegotiation) -> - case ssl_handshake:handle_server_hello_extensions(dtls_record, Random, CipherSuite, - Compression, HelloExt, - dtls_v1:corresponding_tls_version(Version), - SslOpt, ConnectionStates0, Renegotiation) of - #alert{} = Alert -> - Alert; + try ssl_handshake:handle_server_hello_extensions(dtls_record, Random, CipherSuite, + Compression, HelloExt, + dtls_v1:corresponding_tls_version(Version), + SslOpt, ConnectionStates0, Renegotiation) of {ConnectionStates, ProtoExt, Protocol} -> {Version, SessionId, ConnectionStates, ProtoExt, Protocol} + catch throw:Alert -> + Alert end. - %%-------------------------------------------------------------------- enc_handshake(#hello_verify_request{protocol_version = {Major, Minor}, diff --git a/lib/ssl/src/ssl_handshake.erl b/lib/ssl/src/ssl_handshake.erl index 14df1d2e02..a50580e1ea 100644 --- a/lib/ssl/src/ssl_handshake.erl +++ b/lib/ssl/src/ssl_handshake.erl @@ -972,34 +972,30 @@ handle_client_hello_extensions(RecordCB, Random, ClientCipherSuites, #session{cipher_suite = NegotiatedCipherSuite, compression_method = Compression} = Session0, ConnectionStates0, Renegotiation) -> - Session = handle_srp_extension(SRP, Session0), - ConnectionStates = handle_renegotiation_extension(server, RecordCB, Version, Info, - Random, NegotiatedCipherSuite, + Session = handle_srp_extension(SRP, Session0), + ConnectionStates = handle_renegotiation_extension(server, RecordCB, Version, Info, + Random, NegotiatedCipherSuite, ClientCipherSuites, Compression, - ConnectionStates0, Renegotiation, SecureRenegotation), - - ServerHelloExtensions = #hello_extensions{ - renegotiation_info = renegotiation_info(RecordCB, server, - ConnectionStates, Renegotiation), - ec_point_formats = server_ecc_extension(Version, ECCFormat) - }, - + ConnectionStates0, Renegotiation, SecureRenegotation), + + ServerHelloExtensions = #hello_extensions{ + renegotiation_info = renegotiation_info(RecordCB, server, + ConnectionStates, Renegotiation), + ec_point_formats = server_ecc_extension(Version, ECCFormat) + }, + %% If we receive an ALPN extension and have ALPN configured for this connection, %% we handle it. Otherwise we check for the NPN extension. if ALPN =/= undefined, ALPNPreferredProtocols =/= undefined -> - case handle_alpn_extension(ALPNPreferredProtocols, decode_alpn(ALPN)) of - #alert{} = Alert -> - Alert; - Protocol -> - {Session, ConnectionStates, Protocol, - ServerHelloExtensions#hello_extensions{alpn=encode_alpn([Protocol], Renegotiation)}} - end; + Protocol = handle_alpn_extension(ALPNPreferredProtocols, decode_alpn(ALPN)), + {Session, ConnectionStates, Protocol, + ServerHelloExtensions#hello_extensions{alpn=encode_alpn([Protocol], Renegotiation)}}; true -> - ProtocolsToAdvertise = handle_next_protocol_extension(NextProtocolNegotiation, Renegotiation, Opts), + ProtocolsToAdvertise = handle_next_protocol_extension(NextProtocolNegotiation, Renegotiation, Opts), {Session, ConnectionStates, undefined, - ServerHelloExtensions#hello_extensions{next_protocol_negotiation= - encode_protocols_advertised_on_server(ProtocolsToAdvertise)}} + ServerHelloExtensions#hello_extensions{next_protocol_negotiation= + encode_protocols_advertised_on_server(ProtocolsToAdvertise)}} end. handle_server_hello_extensions(RecordCB, Random, CipherSuite, Compression, @@ -1022,12 +1018,8 @@ handle_server_hello_extensions(RecordCB, Random, CipherSuite, Compression, [Protocol] when not Renegotiation -> {ConnectionStates, alpn, Protocol}; undefined -> - case handle_next_protocol(NextProtocolNegotiation, NextProtoSelector, Renegotiation) of - #alert{} = Alert -> - Alert; - Protocol -> - {ConnectionStates, npn, Protocol} - end; + Protocol = handle_next_protocol(NextProtocolNegotiation, NextProtoSelector, Renegotiation), + {ConnectionStates, npn, Protocol}; {error, Reason} -> ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, Reason); [] -> @@ -2189,30 +2181,26 @@ filter_unavailable_ecc_suites(_, Suites) -> handle_renegotiation_extension(Role, RecordCB, Version, Info, Random, NegotiatedCipherSuite, ClientCipherSuites, Compression, ConnectionStates0, Renegotiation, SecureRenegotation) -> - case handle_renegotiation_info(RecordCB, Role, Info, ConnectionStates0, - Renegotiation, SecureRenegotation, - ClientCipherSuites) of - {ok, ConnectionStates} -> - hello_pending_connection_states(RecordCB, Role, - Version, - NegotiatedCipherSuite, - Random, - Compression, - ConnectionStates); - #alert{} = Alert -> - throw(Alert) - end. + {ok, ConnectionStates} = handle_renegotiation_info(RecordCB, Role, Info, ConnectionStates0, + Renegotiation, SecureRenegotation, + ClientCipherSuites), + hello_pending_connection_states(RecordCB, Role, + Version, + NegotiatedCipherSuite, + Random, + Compression, + ConnectionStates). %% Receive protocols, choose one from the list, return it. handle_alpn_extension(_, {error, Reason}) -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, Reason); + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, Reason)); handle_alpn_extension([], _) -> - ?ALERT_REC(?FATAL, ?NO_APPLICATION_PROTOCOL); + throw(?ALERT_REC(?FATAL, ?NO_APPLICATION_PROTOCOL)); handle_alpn_extension([ServerProtocol|Tail], ClientProtocols) -> - case lists:member(ServerProtocol, ClientProtocols) of - true -> ServerProtocol; - false -> handle_alpn_extension(Tail, ClientProtocols) - end. + case lists:member(ServerProtocol, ClientProtocols) of + true -> ServerProtocol; + false -> handle_alpn_extension(Tail, ClientProtocols) + end. handle_next_protocol(undefined, _NextProtocolSelector, _Renegotiating) -> @@ -2225,14 +2213,14 @@ handle_next_protocol(#next_protocol_negotiation{} = NextProtocols, true -> select_next_protocol(decode_next_protocols(NextProtocols), NextProtocolSelector); false -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, unexpected_next_protocol_extension) + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, unexpected_next_protocol_extension)) end. handle_next_protocol_extension(NextProtocolNegotiation, Renegotiation, SslOpts)-> case handle_next_protocol_on_server(NextProtocolNegotiation, Renegotiation, SslOpts) of #alert{} = Alert -> - Alert; + throw(Alert); ProtocolsToAdvertise -> ProtocolsToAdvertise end. @@ -2428,14 +2416,14 @@ handle_renegotiation_info(_RecordCB, client, #renegotiation_info{renegotiated_co true -> {ok, ConnectionStates}; false -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, client_renegotiation) + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, client_renegotiation)) end; handle_renegotiation_info(_RecordCB, server, #renegotiation_info{renegotiated_connection = ClientVerify}, ConnectionStates, true, _, CipherSuites) -> case is_member(?TLS_EMPTY_RENEGOTIATION_INFO_SCSV, CipherSuites) of true -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, {server_renegotiation, empty_renegotiation_info_scsv}); + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, {server_renegotiation, empty_renegotiation_info_scsv})); false -> ConnectionState = ssl_record:current_connection_state(ConnectionStates, read), Data = maps:get(client_verify_data, ConnectionState), @@ -2443,7 +2431,7 @@ handle_renegotiation_info(_RecordCB, server, #renegotiation_info{renegotiated_co true -> {ok, ConnectionStates}; false -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, server_renegotiation) + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, server_renegotiation)) end end; @@ -2453,7 +2441,7 @@ handle_renegotiation_info(RecordCB, client, undefined, ConnectionStates, true, S handle_renegotiation_info(RecordCB, server, undefined, ConnectionStates, true, SecureRenegotation, CipherSuites) -> case is_member(?TLS_EMPTY_RENEGOTIATION_INFO_SCSV, CipherSuites) of true -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, {server_renegotiation, empty_renegotiation_info_scsv}); + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, {server_renegotiation, empty_renegotiation_info_scsv})); false -> handle_renegotiation_info(RecordCB, ConnectionStates, SecureRenegotation) end. @@ -2462,9 +2450,9 @@ handle_renegotiation_info(_RecordCB, ConnectionStates, SecureRenegotation) -> ConnectionState = ssl_record:current_connection_state(ConnectionStates, read), case {SecureRenegotation, maps:get(secure_renegotiation, ConnectionState)} of {_, true} -> - ?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, already_secure); + throw(?ALERT_REC(?FATAL, ?HANDSHAKE_FAILURE, already_secure)); {true, false} -> - ?ALERT_REC(?FATAL, ?NO_RENEGOTIATION); + throw(?ALERT_REC(?FATAL, ?NO_RENEGOTIATION)); {false, false} -> {ok, ConnectionStates} end. diff --git a/lib/ssl/src/tls_handshake.erl b/lib/ssl/src/tls_handshake.erl index 19a5eb0348..65217ad68e 100644 --- a/lib/ssl/src/tls_handshake.erl +++ b/lib/ssl/src/tls_handshake.erl @@ -223,8 +223,6 @@ handle_client_hello_extensions(Version, Type, Random, CipherSuites, HelloExt, Version, SslOpts, Session0, ConnectionStates0, Renegotiation) of - #alert{} = Alert -> - Alert; {Session, ConnectionStates, Protocol, ServerHelloExt} -> {Version, {Type, Session}, ConnectionStates, Protocol, ServerHelloExt, HashSign} @@ -235,14 +233,14 @@ handle_client_hello_extensions(Version, Type, Random, CipherSuites, handle_server_hello_extensions(Version, SessionId, Random, CipherSuite, Compression, HelloExt, SslOpt, ConnectionStates0, Renegotiation) -> - case ssl_handshake:handle_server_hello_extensions(tls_record, Random, CipherSuite, + try ssl_handshake:handle_server_hello_extensions(tls_record, Random, CipherSuite, Compression, HelloExt, Version, SslOpt, ConnectionStates0, - Renegotiation) of - #alert{} = Alert -> - Alert; + Renegotiation) of {ConnectionStates, ProtoExt, Protocol} -> {Version, SessionId, ConnectionStates, ProtoExt, Protocol} + catch throw:Alert -> + Alert end. %%-------------------------------------------------------------------- enc_handshake(#hello_request{}, _Version) -> -- cgit v1.2.3