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Diffstat (limited to 'lib/ssl/src/ssl_record.erl')
| -rw-r--r-- | lib/ssl/src/ssl_record.erl | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/lib/ssl/src/ssl_record.erl b/lib/ssl/src/ssl_record.erl new file mode 100644 index 0000000000..50a45dc16b --- /dev/null +++ b/lib/ssl/src/ssl_record.erl @@ -0,0 +1,439 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2013-2013. All Rights Reserved. +%% +%% The contents of this file are subject to the Erlang Public License, +%% Version 1.1, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Erlang Public License along with this software. If not, it can be +%% retrieved online at http://www.erlang.org/. +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and limitations +%% under the License. +%% +%% %CopyrightEnd% + +%%---------------------------------------------------------------------- +%% Purpose: Handle TLS/SSL/DTLS record protocol. Note epoch is only +%% used by DTLS but handled here so we can avoid code duplication. +%%---------------------------------------------------------------------- + +-module(ssl_record). + +-include("ssl_record.hrl"). +-include("ssl_internal.hrl"). +-include("ssl_cipher.hrl"). +-include("ssl_alert.hrl"). + +%% Connection state handling +-export([init_connection_states/1, + current_connection_state/2, pending_connection_state/2, + activate_pending_connection_state/2, + set_security_params/3, + set_mac_secret/4, + set_master_secret/2, + set_pending_cipher_state/4, + set_renegotiation_flag/2, + set_client_verify_data/3, + set_server_verify_data/3]). + +%% Encoding records +-export([encode_handshake/3, encode_alert_record/3, + encode_change_cipher_spec/2, encode_data/3]). + +%% Compression +-export([compress/3, uncompress/3, compressions/0]). + +-export([is_correct_mac/2]). + +%%==================================================================== +%% Internal application API +%%==================================================================== + +%%-------------------------------------------------------------------- +-spec init_connection_states(client | server) -> #connection_states{}. +%% +%% Description: Creates a connection_states record with appropriate +%% values for the initial SSL connection setup. +%%-------------------------------------------------------------------- +init_connection_states(Role) -> + ConnectionEnd = record_protocol_role(Role), + Current = initial_connection_state(ConnectionEnd), + Pending = empty_connection_state(ConnectionEnd), + #connection_states{current_read = Current, + pending_read = Pending, + current_write = Current, + pending_write = Pending + }. + +%%-------------------------------------------------------------------- +-spec current_connection_state(#connection_states{}, read | write) -> + #connection_state{}. +%% +%% Description: Returns the instance of the connection_state record +%% that is currently defined as the current conection state. +%%-------------------------------------------------------------------- +current_connection_state(#connection_states{current_read = Current}, + read) -> + Current; +current_connection_state(#connection_states{current_write = Current}, + write) -> + Current. + +%%-------------------------------------------------------------------- +-spec pending_connection_state(#connection_states{}, read | write) -> + term(). +%% +%% Description: Returns the instance of the connection_state record +%% that is currently defined as the pending conection state. +%%-------------------------------------------------------------------- +pending_connection_state(#connection_states{pending_read = Pending}, + read) -> + Pending; +pending_connection_state(#connection_states{pending_write = Pending}, + write) -> + Pending. + + +%%-------------------------------------------------------------------- +-spec activate_pending_connection_state(#connection_states{}, read | write) -> + #connection_states{}. +%% +%% Description: Creates a new instance of the connection_states record +%% where the pending state of <Type> has been activated. +%%-------------------------------------------------------------------- +activate_pending_connection_state(States = + #connection_states{current_read = Current, + pending_read = Pending}, + read) -> + NewCurrent = Pending#connection_state{epoch = dtls_next_epoch(Current), + sequence_number = 0}, + SecParams = Pending#connection_state.security_parameters, + ConnectionEnd = SecParams#security_parameters.connection_end, + EmptyPending = empty_connection_state(ConnectionEnd), + SecureRenegotation = NewCurrent#connection_state.secure_renegotiation, + NewPending = EmptyPending#connection_state{secure_renegotiation = SecureRenegotation}, + States#connection_states{current_read = NewCurrent, + pending_read = NewPending + }; + +activate_pending_connection_state(States = + #connection_states{current_write = Current, + pending_write = Pending}, + write) -> + NewCurrent = Pending#connection_state{epoch = dtls_next_epoch(Current), + sequence_number = 0}, + SecParams = Pending#connection_state.security_parameters, + ConnectionEnd = SecParams#security_parameters.connection_end, + EmptyPending = empty_connection_state(ConnectionEnd), + SecureRenegotation = NewCurrent#connection_state.secure_renegotiation, + NewPending = EmptyPending#connection_state{secure_renegotiation = SecureRenegotation}, + States#connection_states{current_write = NewCurrent, + pending_write = NewPending + }. + + +%%-------------------------------------------------------------------- +-spec set_security_params(#security_parameters{}, #security_parameters{}, + #connection_states{}) -> #connection_states{}. +%% +%% Description: Creates a new instance of the connection_states record +%% where the pending states gets its security parameters updated. +%%-------------------------------------------------------------------- +set_security_params(ReadParams, WriteParams, States = + #connection_states{pending_read = Read, + pending_write = Write}) -> + States#connection_states{pending_read = + Read#connection_state{security_parameters = + ReadParams}, + pending_write = + Write#connection_state{security_parameters = + WriteParams} + }. +%%-------------------------------------------------------------------- +-spec set_mac_secret(binary(), binary(), client | server, + #connection_states{}) -> #connection_states{}. +%% +%% Description: update the mac_secret field in pending connection states +%%-------------------------------------------------------------------- +set_mac_secret(ClientWriteMacSecret, ServerWriteMacSecret, client, States) -> + set_mac_secret(ServerWriteMacSecret, ClientWriteMacSecret, States); +set_mac_secret(ClientWriteMacSecret, ServerWriteMacSecret, server, States) -> + set_mac_secret(ClientWriteMacSecret, ServerWriteMacSecret, States). + +set_mac_secret(ReadMacSecret, WriteMacSecret, + States = #connection_states{pending_read = Read, + pending_write = Write}) -> + States#connection_states{ + pending_read = Read#connection_state{mac_secret = ReadMacSecret}, + pending_write = Write#connection_state{mac_secret = WriteMacSecret} + }. + + +%%-------------------------------------------------------------------- +-spec set_master_secret(binary(), #connection_states{}) -> #connection_states{}. +%% +%% Description: Set master_secret in pending connection states +%%-------------------------------------------------------------------- +set_master_secret(MasterSecret, + States = #connection_states{pending_read = Read, + pending_write = Write}) -> + ReadSecPar = Read#connection_state.security_parameters, + Read1 = Read#connection_state{ + security_parameters = ReadSecPar#security_parameters{ + master_secret = MasterSecret}}, + WriteSecPar = Write#connection_state.security_parameters, + Write1 = Write#connection_state{ + security_parameters = WriteSecPar#security_parameters{ + master_secret = MasterSecret}}, + States#connection_states{pending_read = Read1, pending_write = Write1}. + +%%-------------------------------------------------------------------- +-spec set_renegotiation_flag(boolean(), #connection_states{}) -> #connection_states{}. +%% +%% Description: Set secure_renegotiation in pending connection states +%%-------------------------------------------------------------------- +set_renegotiation_flag(Flag, #connection_states{ + current_read = CurrentRead0, + current_write = CurrentWrite0, + pending_read = PendingRead0, + pending_write = PendingWrite0} + = ConnectionStates) -> + CurrentRead = CurrentRead0#connection_state{secure_renegotiation = Flag}, + CurrentWrite = CurrentWrite0#connection_state{secure_renegotiation = Flag}, + PendingRead = PendingRead0#connection_state{secure_renegotiation = Flag}, + PendingWrite = PendingWrite0#connection_state{secure_renegotiation = Flag}, + ConnectionStates#connection_states{current_read = CurrentRead, + current_write = CurrentWrite, + pending_read = PendingRead, + pending_write = PendingWrite}. + +%%-------------------------------------------------------------------- +-spec set_client_verify_data(current_read | current_write | current_both, + binary(), #connection_states{})-> + #connection_states{}. +%% +%% Description: Set verify data in connection states. +%%-------------------------------------------------------------------- +set_client_verify_data(current_read, Data, + #connection_states{current_read = CurrentRead0, + pending_write = PendingWrite0} + = ConnectionStates) -> + CurrentRead = CurrentRead0#connection_state{client_verify_data = Data}, + PendingWrite = PendingWrite0#connection_state{client_verify_data = Data}, + ConnectionStates#connection_states{current_read = CurrentRead, + pending_write = PendingWrite}; +set_client_verify_data(current_write, Data, + #connection_states{pending_read = PendingRead0, + current_write = CurrentWrite0} + = ConnectionStates) -> + PendingRead = PendingRead0#connection_state{client_verify_data = Data}, + CurrentWrite = CurrentWrite0#connection_state{client_verify_data = Data}, + ConnectionStates#connection_states{pending_read = PendingRead, + current_write = CurrentWrite}; +set_client_verify_data(current_both, Data, + #connection_states{current_read = CurrentRead0, + current_write = CurrentWrite0} + = ConnectionStates) -> + CurrentRead = CurrentRead0#connection_state{client_verify_data = Data}, + CurrentWrite = CurrentWrite0#connection_state{client_verify_data = Data}, + ConnectionStates#connection_states{current_read = CurrentRead, + current_write = CurrentWrite}. +%%-------------------------------------------------------------------- +-spec set_server_verify_data(current_read | current_write | current_both, + binary(), #connection_states{})-> + #connection_states{}. +%% +%% Description: Set verify data in pending connection states. +%%-------------------------------------------------------------------- +set_server_verify_data(current_write, Data, + #connection_states{pending_read = PendingRead0, + current_write = CurrentWrite0} + = ConnectionStates) -> + PendingRead = PendingRead0#connection_state{server_verify_data = Data}, + CurrentWrite = CurrentWrite0#connection_state{server_verify_data = Data}, + ConnectionStates#connection_states{pending_read = PendingRead, + current_write = CurrentWrite}; + +set_server_verify_data(current_read, Data, + #connection_states{current_read = CurrentRead0, + pending_write = PendingWrite0} + = ConnectionStates) -> + CurrentRead = CurrentRead0#connection_state{server_verify_data = Data}, + PendingWrite = PendingWrite0#connection_state{server_verify_data = Data}, + ConnectionStates#connection_states{current_read = CurrentRead, + pending_write = PendingWrite}; + +set_server_verify_data(current_both, Data, + #connection_states{current_read = CurrentRead0, + current_write = CurrentWrite0} + = ConnectionStates) -> + CurrentRead = CurrentRead0#connection_state{server_verify_data = Data}, + CurrentWrite = CurrentWrite0#connection_state{server_verify_data = Data}, + ConnectionStates#connection_states{current_read = CurrentRead, + current_write = CurrentWrite}. +%%-------------------------------------------------------------------- +-spec set_pending_cipher_state(#connection_states{}, #cipher_state{}, + #cipher_state{}, client | server) -> + #connection_states{}. +%% +%% Description: Set the cipher state in the specified pending connection state. +%%-------------------------------------------------------------------- +set_pending_cipher_state(#connection_states{pending_read = Read, + pending_write = Write} = States, + ClientState, ServerState, server) -> + States#connection_states{ + pending_read = Read#connection_state{cipher_state = ClientState}, + pending_write = Write#connection_state{cipher_state = ServerState}}; + +set_pending_cipher_state(#connection_states{pending_read = Read, + pending_write = Write} = States, + ClientState, ServerState, client) -> + States#connection_states{ + pending_read = Read#connection_state{cipher_state = ServerState}, + pending_write = Write#connection_state{cipher_state = ClientState}}. + + +%%-------------------------------------------------------------------- +-spec encode_handshake(iolist(), tls_version(), #connection_states{}) -> + {iolist(), #connection_states{}}. +%% +%% Description: Encodes a handshake message to send on the ssl-socket. +%%-------------------------------------------------------------------- +encode_handshake(Frag, Version, ConnectionStates) -> + encode_plain_text(?HANDSHAKE, Version, Frag, ConnectionStates). + +%%-------------------------------------------------------------------- +-spec encode_alert_record(#alert{}, tls_version(), #connection_states{}) -> + {iolist(), #connection_states{}}. +%% +%% Description: Encodes an alert message to send on the ssl-socket. +%%-------------------------------------------------------------------- +encode_alert_record(#alert{level = Level, description = Description}, + Version, ConnectionStates) -> + encode_plain_text(?ALERT, Version, <<?BYTE(Level), ?BYTE(Description)>>, + ConnectionStates). + +%%-------------------------------------------------------------------- +-spec encode_change_cipher_spec(tls_version(), #connection_states{}) -> + {iolist(), #connection_states{}}. +%% +%% Description: Encodes a change_cipher_spec-message to send on the ssl socket. +%%-------------------------------------------------------------------- +encode_change_cipher_spec(Version, ConnectionStates) -> + encode_plain_text(?CHANGE_CIPHER_SPEC, Version, <<1:8>>, ConnectionStates). + +%%-------------------------------------------------------------------- +-spec encode_data(binary(), tls_version(), #connection_states{}) -> + {iolist(), #connection_states{}}. +%% +%% Description: Encodes data to send on the ssl-socket. +%%-------------------------------------------------------------------- +encode_data(Frag, Version, + #connection_states{current_write = #connection_state{ + security_parameters = + #security_parameters{bulk_cipher_algorithm = BCA}}} = + ConnectionStates) -> + Data = split_bin(Frag, ?MAX_PLAIN_TEXT_LENGTH, Version, BCA), + encode_iolist(?APPLICATION_DATA, Data, Version, ConnectionStates). + +uncompress(?NULL, Data, CS) -> + {Data, CS}. + +compress(?NULL, Data, CS) -> + {Data, CS}. + +%%-------------------------------------------------------------------- +-spec compressions() -> [binary()]. +%% +%% Description: return a list of compressions supported (currently none) +%%-------------------------------------------------------------------- +compressions() -> + [?byte(?NULL)]. + +%%-------------------------------------------------------------------- +%%% Internal functions +%%-------------------------------------------------------------------- +empty_connection_state(ConnectionEnd) -> + SecParams = empty_security_params(ConnectionEnd), + #connection_state{security_parameters = SecParams}. + +empty_security_params(ConnectionEnd = ?CLIENT) -> + #security_parameters{connection_end = ConnectionEnd, + client_random = random()}; +empty_security_params(ConnectionEnd = ?SERVER) -> + #security_parameters{connection_end = ConnectionEnd, + server_random = random()}. +random() -> + Secs_since_1970 = calendar:datetime_to_gregorian_seconds( + calendar:universal_time()) - 62167219200, + Random_28_bytes = crypto:rand_bytes(28), + <<?UINT32(Secs_since_1970), Random_28_bytes/binary>>. + +dtls_next_epoch(#connection_state{epoch = undefined}) -> %% SSL/TLS + undefined; +dtls_next_epoch(#connection_state{epoch = Epoch}) -> %% DTLS + Epoch + 1. + +is_correct_mac(Mac, Mac) -> + true; +is_correct_mac(_M,_H) -> + false. + +record_protocol_role(client) -> + ?CLIENT; +record_protocol_role(server) -> + ?SERVER. + +initial_connection_state(ConnectionEnd) -> + #connection_state{security_parameters = + initial_security_params(ConnectionEnd), + sequence_number = 0 + }. + +initial_security_params(ConnectionEnd) -> + SecParams = #security_parameters{connection_end = ConnectionEnd, + compression_algorithm = ?NULL}, + ssl_cipher:security_parameters(?TLS_NULL_WITH_NULL_NULL, SecParams). + + +encode_plain_text(Type, Version, Data, ConnectionStates) -> + RecordCB = protocol_module(Version), + RecordCB:encode_plain_text(Type, Version, Data, ConnectionStates). + +encode_iolist(Type, Data, Version, ConnectionStates0) -> + RecordCB = protocol_module(Version), + {ConnectionStates, EncodedMsg} = + lists:foldl(fun(Text, {CS0, Encoded}) -> + {Enc, CS1} = + RecordCB:encode_plain_text(Type, Version, Text, CS0), + {CS1, [Enc | Encoded]} + end, {ConnectionStates0, []}, Data), + {lists:reverse(EncodedMsg), ConnectionStates}. + +%% 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) when + BCA =/= ?RC4 andalso ({3, 1} == Version orelse + {3, 0} == Version) -> + do_split_bin(Rest, ChunkSize, [[FirstByte]]); +split_bin(Bin, ChunkSize, _, _) -> + do_split_bin(Bin, ChunkSize, []). + +do_split_bin(<<>>, _, Acc) -> + lists:reverse(Acc); +do_split_bin(Bin, ChunkSize, Acc) -> + case Bin of + <<Chunk:ChunkSize/binary, Rest/binary>> -> + do_split_bin(Rest, ChunkSize, [Chunk | Acc]); + _ -> + lists:reverse(Acc, [Bin]) + end. + +protocol_module({3, _}) -> + tls_record; +protocol_module({254, _}) -> + dtls_record. |