diff options
Diffstat (limited to 'lib/ssl/src/tls_record.erl')
-rw-r--r-- | lib/ssl/src/tls_record.erl | 137 |
1 files changed, 69 insertions, 68 deletions
diff --git a/lib/ssl/src/tls_record.erl b/lib/ssl/src/tls_record.erl index f1aca8c801..1776ec2627 100644 --- a/lib/ssl/src/tls_record.erl +++ b/lib/ssl/src/tls_record.erl @@ -75,26 +75,15 @@ init_connection_states(Role, BeastMitigation) -> pending_write => Pending}. %%-------------------------------------------------------------------- --spec get_tls_records(binary(), [tls_version()], binary()) -> {[binary()], binary()} | #alert{}. +-spec get_tls_records(binary(), [tls_version()] | tls_version(), binary()) -> {[binary()], binary()} | #alert{}. %% %% and returns it as a list of tls_compressed binaries also returns leftover %% Description: Given old buffer and new data from TCP, packs up a records %% data %%-------------------------------------------------------------------- -get_tls_records(Data, Versions, Buffer) -> - BinData = list_to_binary([Buffer, Data]), - case erlang:byte_size(BinData) of - N when N >= 3 -> - case assert_version(BinData, Versions) of - true -> - get_tls_records_aux(BinData, []); - false -> - ?ALERT_REC(?FATAL, ?BAD_RECORD_MAC) - end; - _ -> - get_tls_records_aux(BinData, []) - end. - +get_tls_records(Data, Version, Buffer) -> + get_tls_records_aux(Version, <<Buffer/binary, Data/binary>>, []). + %%==================================================================== %% Encoding %%==================================================================== @@ -113,7 +102,7 @@ encode_handshake(Frag, Version, ConnectionStates) -> case iolist_size(Frag) of N when N > ?MAX_PLAIN_TEXT_LENGTH -> - Data = split_bin(iolist_to_binary(Frag), ?MAX_PLAIN_TEXT_LENGTH, Version, BCA, BeastMitigation), + Data = split_bin(iolist_to_binary(Frag), Version, BCA, BeastMitigation), encode_iolist(?HANDSHAKE, Data, Version, ConnectionStates); _ -> encode_plain_text(?HANDSHAKE, Version, Frag, ConnectionStates) @@ -150,7 +139,7 @@ encode_data(Frag, Version, security_parameters := #security_parameters{bulk_cipher_algorithm = BCA}}} = ConnectionStates) -> - Data = split_bin(Frag, ?MAX_PLAIN_TEXT_LENGTH, Version, BCA, BeastMitigation), + Data = split_bin(Frag, Version, BCA, BeastMitigation), encode_iolist(?APPLICATION_DATA, Data, Version, ConnectionStates). %%==================================================================== @@ -176,14 +165,15 @@ decode_cipher_text(#ssl_tls{type = Type, version = Version, BulkCipherAlgo, compression_algorithm = CompAlg} } = ReadState0} = ConnnectionStates0, _) -> - AAD = calc_aad(Type, Version, ReadState0), - case ssl_cipher:decipher_aead(BulkCipherAlgo, CipherS0, Seq, AAD, CipherFragment, Version) of - {PlainFragment, CipherS1} -> + AAD = start_additional_data(Type, Version, ReadState0), + CipherS1 = ssl_record:nonce_seed(BulkCipherAlgo, <<?UINT64(Seq)>>, CipherS0), + case ssl_record:decipher_aead(BulkCipherAlgo, CipherS1, AAD, CipherFragment, Version) of + {PlainFragment, CipherState} -> {Plain, CompressionS1} = ssl_record:uncompress(CompAlg, PlainFragment, CompressionS0), ConnnectionStates = ConnnectionStates0#{ current_read => ReadState0#{ - cipher_state => CipherS1, + cipher_state => CipherState, sequence_number => Seq + 1, compression_state => CompressionS1}}, {CipherText#ssl_tls{fragment = Plain}, ConnnectionStates}; @@ -394,44 +384,51 @@ initial_connection_state(ConnectionEnd, BeastMitigation) -> server_verify_data => undefined }. -assert_version(<<?BYTE(_), ?BYTE(MajVer), ?BYTE(MinVer), _/binary>>, Versions) -> - is_acceptable_version({MajVer, MinVer}, Versions). - -get_tls_records_aux(<<?BYTE(?APPLICATION_DATA),?BYTE(MajVer),?BYTE(MinVer), - ?UINT16(Length), Data:Length/binary, Rest/binary>>, - Acc) -> - get_tls_records_aux(Rest, [#ssl_tls{type = ?APPLICATION_DATA, - version = {MajVer, MinVer}, - fragment = Data} | Acc]); -get_tls_records_aux(<<?BYTE(?HANDSHAKE),?BYTE(MajVer),?BYTE(MinVer), - ?UINT16(Length), - Data:Length/binary, Rest/binary>>, Acc) -> - get_tls_records_aux(Rest, [#ssl_tls{type = ?HANDSHAKE, - version = {MajVer, MinVer}, - fragment = Data} | Acc]); -get_tls_records_aux(<<?BYTE(?ALERT),?BYTE(MajVer),?BYTE(MinVer), - ?UINT16(Length), Data:Length/binary, - Rest/binary>>, Acc) -> - get_tls_records_aux(Rest, [#ssl_tls{type = ?ALERT, - version = {MajVer, MinVer}, +get_tls_records_aux({MajVer, MinVer} = Version, <<?BYTE(Type),?BYTE(MajVer),?BYTE(MinVer), + ?UINT16(Length), Data:Length/binary, Rest/binary>>, + Acc) when Type == ?APPLICATION_DATA; + Type == ?HANDSHAKE; + Type == ?ALERT; + Type == ?CHANGE_CIPHER_SPEC -> + get_tls_records_aux(Version, Rest, [#ssl_tls{type = Type, + version = Version, fragment = Data} | Acc]); -get_tls_records_aux(<<?BYTE(?CHANGE_CIPHER_SPEC),?BYTE(MajVer),?BYTE(MinVer), - ?UINT16(Length), Data:Length/binary, Rest/binary>>, - Acc) -> - get_tls_records_aux(Rest, [#ssl_tls{type = ?CHANGE_CIPHER_SPEC, - version = {MajVer, MinVer}, - fragment = Data} | Acc]); -get_tls_records_aux(<<0:1, _CT:7, ?BYTE(_MajVer), ?BYTE(_MinVer), - ?UINT16(Length), _/binary>>, +get_tls_records_aux(Versions, <<?BYTE(Type),?BYTE(MajVer),?BYTE(MinVer), + ?UINT16(Length), Data:Length/binary, Rest/binary>>, + Acc) when is_list(Versions) andalso + ((Type == ?APPLICATION_DATA) + orelse + (Type == ?HANDSHAKE) + orelse + (Type == ?ALERT) + orelse + (Type == ?CHANGE_CIPHER_SPEC)) -> + case is_acceptable_version({MajVer, MinVer}, Versions) of + true -> + get_tls_records_aux(Versions, Rest, [#ssl_tls{type = Type, + version = {MajVer, MinVer}, + fragment = Data} | Acc]); + false -> + ?ALERT_REC(?FATAL, ?BAD_RECORD_MAC) + end; +get_tls_records_aux(_, <<?BYTE(Type),?BYTE(_MajVer),?BYTE(_MinVer), + ?UINT16(Length), _:Length/binary, _Rest/binary>>, + _) when Type == ?APPLICATION_DATA; + Type == ?HANDSHAKE; + Type == ?ALERT; + Type == ?CHANGE_CIPHER_SPEC -> + ?ALERT_REC(?FATAL, ?BAD_RECORD_MAC); +get_tls_records_aux(_, <<0:1, _CT:7, ?BYTE(_MajVer), ?BYTE(_MinVer), + ?UINT16(Length), _/binary>>, _Acc) when Length > ?MAX_CIPHER_TEXT_LENGTH -> ?ALERT_REC(?FATAL, ?RECORD_OVERFLOW); -get_tls_records_aux(Data, Acc) -> +get_tls_records_aux(_, Data, Acc) -> case size(Data) =< ?MAX_CIPHER_TEXT_LENGTH + ?INITIAL_BYTES of true -> {lists:reverse(Acc), Data}; false -> ?ALERT_REC(?FATAL, ?UNEXPECTED_MESSAGE) - end. + end. %%-------------------------------------------------------------------- encode_plain_text(Type, Version, Data, #{current_write := Write0} = ConnectionStates) -> {CipherFragment, Write1} = do_encode_plain_text(Type, Version, Data, Write0), @@ -453,15 +450,20 @@ encode_iolist(Type, Data, Version, ConnectionStates0) -> {lists:reverse(EncodedMsg), ConnectionStates}. %%-------------------------------------------------------------------- do_encode_plain_text(Type, Version, Data, #{compression_state := CompS0, - security_parameters := + cipher_state := CipherS0, + sequence_number := Seq, + security_parameters := #security_parameters{ cipher_type = ?AEAD, + bulk_cipher_algorithm = BCAlg, compression_algorithm = CompAlg} } = WriteState0) -> {Comp, CompS1} = ssl_record:compress(CompAlg, Data, CompS0), - WriteState1 = WriteState0#{compression_state => CompS1}, - AAD = calc_aad(Type, Version, WriteState1), - ssl_record:cipher_aead(Version, Comp, WriteState1, AAD); + CipherS = ssl_record:nonce_seed(BCAlg, <<?UINT64(Seq)>>, CipherS0), + WriteState = WriteState0#{compression_state => CompS1, + cipher_state => CipherS}, + AAD = start_additional_data(Type, Version, WriteState), + ssl_record:cipher_aead(Version, Comp, WriteState, AAD); do_encode_plain_text(Type, Version, Data, #{compression_state := CompS0, security_parameters := #security_parameters{compression_algorithm = CompAlg} @@ -473,33 +475,32 @@ do_encode_plain_text(Type, Version, Data, #{compression_state := CompS0, do_encode_plain_text(_,_,_,CS) -> exit({cs, CS}). %%-------------------------------------------------------------------- -calc_aad(Type, {MajVer, MinVer}, +start_additional_data(Type, {MajVer, MinVer}, #{sequence_number := SeqNo}) -> <<?UINT64(SeqNo), ?BYTE(Type), ?BYTE(MajVer), ?BYTE(MinVer)>>. %% 1/n-1 splitting countermeasure Rizzo/Duong-Beast, RC4 chiphers are %% not vulnerable to this attack. -split_bin(<<FirstByte:8, Rest/binary>>, ChunkSize, Version, BCA, one_n_minus_one) when +split_bin(<<FirstByte:8, Rest/binary>>, Version, BCA, one_n_minus_one) when BCA =/= ?RC4 andalso ({3, 1} == Version orelse {3, 0} == Version) -> - do_split_bin(Rest, ChunkSize, [[FirstByte]]); + [[FirstByte]|do_split_bin(Rest)]; %% 0/n splitting countermeasure for clients that are incompatible with 1/n-1 %% splitting. -split_bin(Bin, ChunkSize, Version, BCA, zero_n) when +split_bin(Bin, Version, BCA, zero_n) when BCA =/= ?RC4 andalso ({3, 1} == Version orelse {3, 0} == Version) -> - do_split_bin(Bin, ChunkSize, [[<<>>]]); -split_bin(Bin, ChunkSize, _, _, _) -> - do_split_bin(Bin, ChunkSize, []). + [<<>>|do_split_bin(Bin)]; +split_bin(Bin, _, _, _) -> + do_split_bin(Bin). -do_split_bin(<<>>, _, Acc) -> - lists:reverse(Acc); -do_split_bin(Bin, ChunkSize, Acc) -> +do_split_bin(<<>>) -> []; +do_split_bin(Bin) -> case Bin of - <<Chunk:ChunkSize/binary, Rest/binary>> -> - do_split_bin(Rest, ChunkSize, [Chunk | Acc]); + <<Chunk:?MAX_PLAIN_TEXT_LENGTH/binary, Rest/binary>> -> + [Chunk|do_split_bin(Rest)]; _ -> - lists:reverse(Acc, [Bin]) + [Bin] end. %%-------------------------------------------------------------------- lowest_list_protocol_version(Ver, []) -> |