diff options
Diffstat (limited to 'lib/ssl/src/dtls_handshake.erl')
| -rw-r--r-- | lib/ssl/src/dtls_handshake.erl | 163 |
1 files changed, 91 insertions, 72 deletions
diff --git a/lib/ssl/src/dtls_handshake.erl b/lib/ssl/src/dtls_handshake.erl index 37a46b862e..6071eece13 100644 --- a/lib/ssl/src/dtls_handshake.erl +++ b/lib/ssl/src/dtls_handshake.erl @@ -16,6 +16,11 @@ %% limitations under the License. %% %% %CopyrightEnd% + +%%---------------------------------------------------------------------- +%% Purpose: Help funtions for handling the DTLS (specific parts of) +%%% SSL/TLS/DTLS handshake protocol +%%---------------------------------------------------------------------- -module(dtls_handshake). -include("dtls_connection.hrl"). @@ -24,15 +29,21 @@ -include("ssl_internal.hrl"). -include("ssl_alert.hrl"). +%% Handshake handling -export([client_hello/8, client_hello/9, cookie/4, hello/4, - hello_verify_request/2, get_dtls_handshake/3, fragment_handshake/2, - handshake_bin/2, encode_handshake/3]). + hello_verify_request/2]). + +%% Handshake encoding +-export([fragment_handshake/2, encode_handshake/3]). + +%% Handshake decodeing +-export([get_dtls_handshake/3]). -type dtls_handshake() :: #client_hello{} | #hello_verify_request{} | ssl_handshake:ssl_handshake(). %%==================================================================== -%% Internal application API +%% Handshake handling %%==================================================================== %%-------------------------------------------------------------------- -spec client_hello(host(), inet:port_number(), ssl_record:connection_states(), @@ -56,7 +67,8 @@ client_hello(Host, Port, ConnectionStates, SslOpts, %%-------------------------------------------------------------------- client_hello(Host, Port, Cookie, ConnectionStates, #ssl_options{versions = Versions, - ciphers = UserSuites + ciphers = UserSuites, + fallback = Fallback } = SslOpts, Cache, CacheCb, Renegotiation, OwnCert) -> Version = dtls_record:highest_protocol_version(Versions), @@ -66,12 +78,15 @@ client_hello(Host, Port, Cookie, ConnectionStates, CipherSuites = ssl_handshake:available_suites(UserSuites, TLSVersion), Extensions = ssl_handshake:client_hello_extensions(TLSVersion, CipherSuites, - SslOpts, ConnectionStates, Renegotiation), + SslOpts, ConnectionStates, + Renegotiation), Id = ssl_session:client_id({Host, Port, SslOpts}, Cache, CacheCb, OwnCert), #client_hello{session_id = Id, client_version = Version, - cipher_suites = ssl_handshake:cipher_suites(CipherSuites, Renegotiation), + cipher_suites = + ssl_handshake:cipher_suites(CipherSuites, + Renegotiation, Fallback), compression_methods = ssl_record:compressions(), random = SecParams#security_parameters.client_random, cookie = Cookie, @@ -87,11 +102,11 @@ hello(#server_hello{server_version = Version, random = Random, case dtls_record:is_acceptable_version(Version, SupportedVersions) of true -> handle_server_hello_extensions(Version, SessionId, Random, CipherSuite, - Compression, HelloExt, SslOpt, ConnectionStates0, Renegotiation); + Compression, HelloExt, SslOpt, + ConnectionStates0, Renegotiation); false -> ?ALERT_REC(?FATAL, ?PROTOCOL_VERSION) end; - hello(#client_hello{client_version = ClientVersion} = Hello, #ssl_options{versions = Versions} = SslOpts, Info, Renegotiation) -> @@ -107,7 +122,7 @@ cookie(Key, Address, Port, #client_hello{client_version = {Major, Minor}, <<?BYTE(Major), ?BYTE(Minor)>>, Random, SessionId, CipherSuites, CompressionMethods], crypto:hmac(sha, Key, CookieData). - +%%-------------------------------------------------------------------- -spec hello_verify_request(binary(), dtls_record:dtls_version()) -> #hello_verify_request{}. %% %% Description: Creates a hello verify request message sent by server to @@ -117,11 +132,8 @@ hello_verify_request(Cookie, Version) -> #hello_verify_request{protocol_version = Version, cookie = Cookie}. %%-------------------------------------------------------------------- - -encode_handshake(Handshake, Version, Seq) -> - {MsgType, Bin} = enc_handshake(Handshake, Version), - Len = byte_size(Bin), - [MsgType, ?uint24(Len), ?uint16(Seq), ?uint24(0), ?uint24(Len), Bin]. +%%% Handshake encoding +%%-------------------------------------------------------------------- fragment_handshake(Bin, _) when is_binary(Bin)-> %% This is the change_cipher_spec not a "real handshake" but part of the flight @@ -129,10 +141,15 @@ fragment_handshake(Bin, _) when is_binary(Bin)-> fragment_handshake([MsgType, Len, Seq, _, Len, Bin], Size) -> Bins = bin_fragments(Bin, Size), handshake_fragments(MsgType, Seq, Len, Bins, []). +encode_handshake(Handshake, Version, Seq) -> + {MsgType, Bin} = enc_handshake(Handshake, Version), + Len = byte_size(Bin), + [MsgType, ?uint24(Len), ?uint16(Seq), ?uint24(0), ?uint24(Len), Bin]. + +%%-------------------------------------------------------------------- +%%% Handshake decodeing +%%-------------------------------------------------------------------- -handshake_bin([Type, Length, Data], Seq) -> - handshake_bin(Type, Length, Seq, Data). - %%-------------------------------------------------------------------- -spec get_dtls_handshake(dtls_record:dtls_version(), binary(), #protocol_buffers{}) -> {[dtls_handshake()], #protocol_buffers{}}. @@ -147,16 +164,19 @@ get_dtls_handshake(Version, Fragment, ProtocolBuffers) -> %%-------------------------------------------------------------------- %%% Internal functions %%-------------------------------------------------------------------- -handle_client_hello(Version, #client_hello{session_id = SugesstedId, - cipher_suites = CipherSuites, - compression_methods = Compressions, - random = Random, - extensions = - #hello_extensions{elliptic_curves = Curves, - signature_algs = ClientHashSigns} = HelloExt}, +handle_client_hello(Version, + #client_hello{session_id = SugesstedId, + cipher_suites = CipherSuites, + compression_methods = Compressions, + random = Random, + extensions = + #hello_extensions{elliptic_curves = Curves, + signature_algs = ClientHashSigns} + = HelloExt}, #ssl_options{versions = Versions, signature_algs = SupportedHashSigns} = SslOpts, - {Port, Session0, Cache, CacheCb, ConnectionStates0, Cert, _}, Renegotiation) -> + {Port, Session0, Cache, CacheCb, ConnectionStates0, Cert, _}, + Renegotiation) -> case dtls_record:is_acceptable_version(Version, Versions) of true -> TLSVersion = dtls_v1:corresponding_tls_version(Version), @@ -164,14 +184,15 @@ handle_client_hello(Version, #client_hello{session_id = SugesstedId, ClientHashSigns, SupportedHashSigns, Cert,TLSVersion), ECCCurve = ssl_handshake:select_curve(Curves, ssl_handshake:supported_ecc(TLSVersion)), {Type, #session{cipher_suite = CipherSuite} = Session1} - = ssl_handshake:select_session(SugesstedId, CipherSuites, AvailableHashSigns, Compressions, + = ssl_handshake:select_session(SugesstedId, CipherSuites, + AvailableHashSigns, Compressions, Port, Session0#session{ecc = ECCCurve}, TLSVersion, SslOpts, Cache, CacheCb, Cert), case CipherSuite of no_suite -> ?ALERT_REC(?FATAL, ?INSUFFICIENT_SECURITY); _ -> - {KeyExAlg,_,_,_} = ssl_cipher:suite_definition(CipherSuite), + #{key_exchange := KeyExAlg} = ssl_cipher:suite_definition(CipherSuite), case ssl_handshake:select_hashsign(ClientHashSigns, Cert, KeyExAlg, SupportedHashSigns, TLSVersion) of #alert{} = Alert -> @@ -190,7 +211,8 @@ handle_client_hello_extensions(Version, Type, Random, CipherSuites, HelloExt, SslOpts, Session0, ConnectionStates0, Renegotiation, HashSign) -> try ssl_handshake:handle_client_hello_extensions(dtls_record, Random, CipherSuites, HelloExt, dtls_v1:corresponding_tls_version(Version), - SslOpts, Session0, ConnectionStates0, Renegotiation) of + SslOpts, Session0, + ConnectionStates0, Renegotiation) of #alert{} = Alert -> Alert; {Session, ConnectionStates, Protocol, ServerHelloExt} -> @@ -212,7 +234,7 @@ handle_server_hello_extensions(Version, SessionId, Random, CipherSuite, end. -%%%%%%% Encodeing %%%%%%%%%%%%% +%%-------------------------------------------------------------------- enc_handshake(#hello_verify_request{protocol_version = {Major, Minor}, cookie = Cookie}, _Version) -> @@ -220,7 +242,6 @@ enc_handshake(#hello_verify_request{protocol_version = {Major, Minor}, {?HELLO_VERIFY_REQUEST, <<?BYTE(Major), ?BYTE(Minor), ?BYTE(CookieLength), Cookie:CookieLength/binary>>}; - enc_handshake(#hello_request{}, _Version) -> {?HELLO_REQUEST, <<>>}; enc_handshake(#client_hello{client_version = {Major, Minor}, @@ -243,19 +264,29 @@ enc_handshake(#client_hello{client_version = {Major, Minor}, ?BYTE(CookieLength), Cookie/binary, ?UINT16(CsLength), BinCipherSuites/binary, ?BYTE(CmLength), BinCompMethods/binary, ExtensionsBin/binary>>}; - enc_handshake(#server_hello{} = HandshakeMsg, Version) -> {Type, <<?BYTE(Major), ?BYTE(Minor), Rest/binary>>} = ssl_handshake:encode_handshake(HandshakeMsg, Version), {DTLSMajor, DTLSMinor} = dtls_v1:corresponding_dtls_version({Major, Minor}), {Type, <<?BYTE(DTLSMajor), ?BYTE(DTLSMinor), Rest/binary>>}; - enc_handshake(HandshakeMsg, Version) -> ssl_handshake:encode_handshake(HandshakeMsg, dtls_v1:corresponding_tls_version(Version)). +handshake_bin(#handshake_fragment{ + type = Type, + length = Len, + message_seq = Seq, + fragment_length = Len, + fragment_offset = 0, + fragment = Fragment}) -> + handshake_bin(Type, Len, Seq, Fragment). +handshake_bin(Type, Length, Seq, FragmentData) -> + <<?BYTE(Type), ?UINT24(Length), + ?UINT16(Seq), ?UINT24(0), ?UINT24(Length), + FragmentData:Length/binary>>. + bin_fragments(Bin, Size) -> bin_fragments(Bin, size(Bin), Size, 0, []). - bin_fragments(Bin, BinSize, FragSize, Offset, Fragments) -> case (BinSize - Offset - FragSize) > 0 of true -> @@ -279,7 +310,7 @@ address_to_bin({A,B,C,D}, Port) -> address_to_bin({A,B,C,D,E,F,G,H}, Port) -> <<A:16,B:16,C:16,D:16,E:16,F:16,G:16,H:16,Port:16>>. -%%%%%%% Decodeing %%%%%%%%%%%%% +%%-------------------------------------------------------------------- handle_fragments(Version, FragmentData, Buffers0, Acc) -> Fragments = decode_handshake_fragments(FragmentData), @@ -322,7 +353,6 @@ decode_handshake(_Version, ?CLIENT_HELLO, <<?UINT24(_), ?UINT16(_), compression_methods = Comp_methods, extensions = DecodedExtensions }; - decode_handshake(_Version, ?HELLO_VERIFY_REQUEST, <<?UINT24(_), ?UINT16(_), ?UINT24(_), ?UINT24(_), ?BYTE(Major), ?BYTE(Minor), @@ -330,7 +360,6 @@ decode_handshake(_Version, ?HELLO_VERIFY_REQUEST, <<?UINT24(_), ?UINT16(_), Cookie:CookieLength/binary>>) -> #hello_verify_request{protocol_version = {Major, Minor}, cookie = Cookie}; - decode_handshake(Version, Tag, <<?UINT24(_), ?UINT16(_), ?UINT24(_), ?UINT24(_), Msg/binary>>) -> %% DTLS specifics stripped @@ -370,9 +399,10 @@ reassemble(Version, #handshake_fragment{message_seq = Seq} = Fragment, end; reassemble(_, #handshake_fragment{message_seq = FragSeq} = Fragment, #protocol_buffers{dtls_handshake_next_seq = Seq, - dtls_handshake_later_fragments = LaterFragments} = Buffers0) when FragSeq > Seq-> - {more_data, - Buffers0#protocol_buffers{dtls_handshake_later_fragments = [Fragment | LaterFragments]}}; + dtls_handshake_later_fragments = LaterFragments} + = Buffers0) when FragSeq > Seq-> + {more_data, + Buffers0#protocol_buffers{dtls_handshake_later_fragments = [Fragment | LaterFragments]}}; reassemble(_, _, Buffers) -> %% Disregard fragments FragSeq < Seq {more_data, Buffers}. @@ -396,26 +426,6 @@ merge_fragment(Frag0, [Frag1 | Rest]) -> Frag -> merge_fragment(Frag, Rest) end. - -is_complete_handshake(#handshake_fragment{length = Length, fragment_length = Length}) -> - true; -is_complete_handshake(_) -> - false. - -next_fragments(LaterFragments) -> - case lists:keysort(#handshake_fragment.message_seq, LaterFragments) of - [] -> - {[], []}; - [#handshake_fragment{message_seq = Seq} | _] = Fragments -> - split_frags(Fragments, Seq, []) - end. - -split_frags([#handshake_fragment{message_seq = Seq} = Frag | Rest], Seq, Acc) -> - split_frags(Rest, Seq, [Frag | Acc]); -split_frags(Frags, _, Acc) -> - {lists:reverse(Acc), Frags}. - - %% Duplicate merge_fragments(#handshake_fragment{ fragment_offset = PreviousOffSet, @@ -486,17 +496,26 @@ merge_fragments(#handshake_fragment{ %% No merge there is a gap merge_fragments(Previous, Current) -> [Previous, Current]. - -handshake_bin(#handshake_fragment{ - type = Type, - length = Len, - message_seq = Seq, - fragment_length = Len, - fragment_offset = 0, - fragment = Fragment}) -> - handshake_bin(Type, Len, Seq, Fragment). -handshake_bin(Type, Length, Seq, FragmentData) -> - <<?BYTE(Type), ?UINT24(Length), - ?UINT16(Seq), ?UINT24(0), ?UINT24(Length), - FragmentData:Length/binary>>. +next_fragments(LaterFragments) -> + case lists:keysort(#handshake_fragment.message_seq, LaterFragments) of + [] -> + {[], []}; + [#handshake_fragment{message_seq = Seq} | _] = Fragments -> + split_frags(Fragments, Seq, []) + end. + +split_frags([#handshake_fragment{message_seq = Seq} = Frag | Rest], Seq, Acc) -> + split_frags(Rest, Seq, [Frag | Acc]); +split_frags(Frags, _, Acc) -> + {lists:reverse(Acc), Frags}. + +is_complete_handshake(#handshake_fragment{length = Length, fragment_length = Length}) -> + true; +is_complete_handshake(_) -> + false. + + + + + |