Merge branch 'ia/ssl/continue-dtls-and-specs'

* ia/ssl/continue-dtls-and-specs:
  ssl: Avoid dialyzer warnings in dtls code
  ssl: Improve type specs
  ssl: Refactor and start implementing dtls_connection.erl

1 files changed, 220 insertions, 182 deletions

diff --git a/lib/ssl/src/dtls_handshake.erl b/lib/ssl/src/dtls_handshake.erl
index 5db2434753..31d525b295 100644
--- a/lib/ssl/src/dtls_handshake.erl
+++ b/lib/ssl/src/dtls_handshake.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2013-2013. All Rights Reserved.
+%% Copyright Ericsson AB 2013-2014. 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
@@ -20,11 +20,15 @@
 -include("dtls_handshake.hrl").
 -include("dtls_record.hrl").
 -include("ssl_internal.hrl").
+-include("ssl_alert.hrl").
 
--export([client_hello/8, client_hello/9, hello/3,
+-export([client_hello/8, client_hello/9, hello/4,
 	 get_dtls_handshake/2,
-	 dtls_handshake_new_flight/1, dtls_handshake_new_epoch/1,
-	 encode_handshake/4]).
+	 %%dtls_handshake_new_flight/1, dtls_handshake_new_epoch/1,
+	 encode_handshake/3]).
+
+-type dtls_handshake() :: #client_hello{} | #hello_verify_request{} | 
+			  ssl_handshake:ssl_handshake().
 
 %%====================================================================
 %% Internal application API
@@ -54,12 +58,12 @@ client_hello(Host, Port, Cookie, ConnectionStates,
 			  ciphers = UserSuites
 			 } = SslOpts,
 	     Cache, CacheCb, Renegotiation, OwnCert) ->
-    Version = dtls_record:highest_protocol_version(Versions),
+    Version =  dtls_record:highest_protocol_version(Versions),
     Pending = ssl_record:pending_connection_state(ConnectionStates, read),
     SecParams = Pending#connection_state.security_parameters,
     CipherSuites = ssl_handshake:available_suites(UserSuites, Version),
 
-    Extensions = ssl_handshake:client_hello_extensions(Host, Version, CipherSuites,
+    Extensions = ssl_handshake:client_hello_extensions(Host, dtls_v1:corresponding_tls_version(Version), CipherSuites,
 						SslOpts, ConnectionStates, Renegotiation),
 
     Id = ssl_session:client_id({Host, Port, SslOpts}, Cache, CacheCb, OwnCert),
@@ -73,163 +77,197 @@ client_hello(Host, Port, Cookie, ConnectionStates,
 		  extensions = Extensions
 		 }.
 
-hello(Address, Port,
-      #ssl_tls{epoch = _Epoch, record_seq = _Seq,
-	       version = Version} = Record) ->
-    {[{Hello, _}], _, _} =
-	get_dtls_handshake(Record,
-			   dtls_handshake_new_flight(undefined)),
-    #client_hello{client_version = {Major, Minor},
-		  random = Random,
-		  session_id = SessionId,
-		  cipher_suites = CipherSuites,
-		  compression_methods = CompressionMethods} = Hello,
-    CookieData = [address_to_bin(Address, Port),
-		  <<?BYTE(Major), ?BYTE(Minor)>>,
-		  Random, SessionId, CipherSuites, CompressionMethods],
-    Cookie = crypto:hmac(sha, <<"secret">>, CookieData),
-
-    case Hello of
-	#client_hello{cookie = Cookie} ->
-	    accept;
-	_ ->
-	    %% generate HelloVerifyRequest
-	    HelloVerifyRequest = encode_handshake(#hello_verify_request{protocol_version = Version,
-									  cookie = Cookie},
-						    Version, 0, 1400),
-	    {reply, HelloVerifyRequest}
-    end.
+hello(#server_hello{server_version = Version, random = Random,
+		    cipher_suite = CipherSuite,
+		    compression_method = Compression,
+		    session_id = SessionId, extensions = HelloExt},
+      #ssl_options{versions = SupportedVersions} = SslOpt,
+      ConnectionStates0, Renegotiation) ->
+    case dtls_record:is_acceptable_version(Version, SupportedVersions) of
+	true ->
+	    handle_server_hello_extensions(Version, SessionId, Random, CipherSuite,
+					   Compression, HelloExt, SslOpt, ConnectionStates0, Renegotiation);
+	false ->
+	    ?ALERT_REC(?FATAL, ?PROTOCOL_VERSION)
+    end;
 
-%%--------------------------------------------------------------------
-encode_handshake(Package, Version, MsgSeq, Mss) ->
-    {MsgType, Bin} = enc_hs(Package, Version),
+hello(#client_hello{client_version = ClientVersion}, _Options, {_,_,_,_,ConnectionStates,_}, _Renegotiation) ->      
+    %% Return correct typ to make dialyzer happy until we have time to make the real imp.
+    {ClientVersion, {new, #session{}}, ConnectionStates, #hello_extensions{}}.
+
+%% hello(Address, Port,
+%%       #ssl_tls{epoch = _Epoch, sequence_number = _Seq,
+%% 	       version = Version} = Record) ->
+%%     case get_dtls_handshake(Record,
+%% 				dtls_handshake_new_flight(undefined)) of
+%% 	{[Hello | _], _} ->
+%% 	    hello(Address, Port, Version, Hello);
+%% 	{retransmit, HandshakeState} ->
+%% 	    {retransmit, HandshakeState}
+%%     end.
+					     
+%% hello(Address, Port, Version, Hello) ->
+%%     #client_hello{client_version = {Major, Minor},
+%% 		  random = Random,
+%% 		  session_id = SessionId,
+%% 		  cipher_suites = CipherSuites,
+%% 		  compression_methods = CompressionMethods} = Hello,
+%%     CookieData = [address_to_bin(Address, Port),
+%% 		  <<?BYTE(Major), ?BYTE(Minor)>>,
+%% 		  Random, SessionId, CipherSuites, CompressionMethods],
+%%     Cookie = crypto:hmac(sha, <<"secret">>, CookieData),
+
+%%     case Hello of
+%% 	#client_hello{cookie = Cookie} ->
+%% 	    accept;
+%% 	_ ->
+%% 	    %% generate HelloVerifyRequest
+%% 	    HelloVerifyRequest = enc_hs(#hello_verify_request{protocol_version = Version,
+%% 									  cookie = Cookie},
+%% 						    Version, 0, 1400),
+%% 	    {reply, HelloVerifyRequest}
+%%     end.
+
+%% %%--------------------------------------------------------------------
+encode_handshake(Handshake, Version, MsgSeq) ->
+    {MsgType, Bin} = enc_handshake(Handshake, Version),
     Len = byte_size(Bin),
-    HsHistory = [MsgType, ?uint24(Len), ?uint16(MsgSeq), ?uint24(0), ?uint24(Len), Bin],
-    BinMsg = dtls_split_handshake(Mss, MsgType, Len, MsgSeq, Bin, 0, []),
-    {HsHistory, BinMsg}.
+    EncHandshake = [MsgType, ?uint24(Len), ?uint16(MsgSeq), ?uint24(0), ?uint24(Len), Bin],
+    FragmentedHandshake = dtls_fragment(erlang:iolist_size(EncHandshake), MsgType, Len, MsgSeq, Bin, 0, []),
+    {EncHandshake, FragmentedHandshake}.
 
-%--------------------------------------------------------------------
+%%--------------------------------------------------------------------
 -spec get_dtls_handshake(#ssl_tls{}, #dtls_hs_state{} | binary()) ->
-     {[dtls_handshake()], #dtls_hs_state{}} | {retransmit, #dtls_hs_state{}}.
-%
-% Description: Given a DTLS state and new data from ssl_record, collects
-% and returns it as a list of handshake messages, also returns a new
-% DTLS state
-%--------------------------------------------------------------------
-% get_dtls_handshake(Record, <<>>) ->
-%     get_dtls_handshake_aux(Record, dtls_hs_state_init());
+				{[dtls_handshake()], #dtls_hs_state{}} | {retransmit, #dtls_hs_state{}}.
+%%
+%% Description: Given a DTLS state and new data from ssl_record, collects
+%% and returns it as a list of handshake messages, also returns a new
+%% DTLS state
+%%--------------------------------------------------------------------
+get_dtls_handshake(Record, <<>>) ->
+    get_dtls_handshake_aux(Record, #dtls_hs_state{}); %% Init handshake state!?
 get_dtls_handshake(Record, HsState) ->
     get_dtls_handshake_aux(Record, HsState).
 
-%--------------------------------------------------------------------
--spec dtls_handshake_new_epoch(#dtls_hs_state{}) -> #dtls_hs_state{}.
-%
-% Description: Reset the DTLS decoder state for a new Epoch
-%--------------------------------------------------------------------
-% dtls_handshake_new_epoch(<<>>) ->
-%     dtls_hs_state_init();
-dtls_handshake_new_epoch(HsState) ->
-    HsState#dtls_hs_state{highest_record_seq = 0,
-			  starting_read_seq = HsState#dtls_hs_state.current_read_seq,
-			  fragments = gb_trees:empty(), completed = []}.
-
-%--------------------------------------------------------------------
--spec dtls_handshake_new_flight(integer() | undefined) -> #dtls_hs_state{}.
-%
-% Description: Init the DTLS decoder state for a new Flight
-dtls_handshake_new_flight(ExpectedReadReq) ->
-    #dtls_hs_state{current_read_seq = ExpectedReadReq,
-		   highest_record_seq = 0,
-		   starting_read_seq = 0,
-		   fragments = gb_trees:empty(), completed = []}.
+%% %%--------------------------------------------------------------------
+%% -spec dtls_handshake_new_epoch(#dtls_hs_state{}) -> #dtls_hs_state{}.
+%% %%
+%% %% Description: Reset the DTLS decoder state for a new Epoch
+%% %%--------------------------------------------------------------------
+%% dtls_handshake_new_epoch(<<>>) ->
+%%     dtls_hs_state_init();
+%% dtls_handshake_new_epoch(HsState) ->
+%%     HsState#dtls_hs_state{highest_record_seq = 0,
+%%   			  starting_read_seq = HsState#dtls_hs_state.current_read_seq,
+%%   			  fragments = gb_trees:empty(), completed = []}.
+
+%% %--------------------------------------------------------------------
+%% -spec dtls_handshake_new_flight(integer() | undefined) -> #dtls_hs_state{}.
+%% %
+%% % Description: Init the DTLS decoder state for a new Flight
+%% dtls_handshake_new_flight(ExpectedReadReq) ->
+%%     #dtls_hs_state{current_read_seq = ExpectedReadReq,
+%% 		   highest_record_seq = 0,
+%% 		   starting_read_seq = 0,
+%% 		   fragments = gb_trees:empty(), completed = []}.
 
 %%--------------------------------------------------------------------
 %%% Internal functions
 %%--------------------------------------------------------------------
+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, Version,
+						      SslOpt, ConnectionStates0, Renegotiation) of
+	#alert{} = Alert ->
+	    Alert;
+	{ConnectionStates, Protocol} ->
+	    {Version, SessionId, ConnectionStates, Protocol}
+    end.
 
-dtls_split_handshake(Mss, MsgType, Len, MsgSeq, Bin, Offset, Acc)
+dtls_fragment(Mss, MsgType, Len, MsgSeq, Bin, Offset, Acc)
   when byte_size(Bin) + 12 < Mss ->
     FragmentLen = byte_size(Bin),
     BinMsg = [MsgType, ?uint24(Len), ?uint16(MsgSeq), ?uint24(Offset), ?uint24(FragmentLen), Bin],
     lists:reverse([BinMsg|Acc]);
-dtls_split_handshake(Mss, MsgType, Len, MsgSeq, Bin, Offset, Acc) ->
+dtls_fragment(Mss, MsgType, Len, MsgSeq, Bin, Offset, Acc) ->
     FragmentLen = Mss - 12,
     <<Fragment:FragmentLen/bytes, Rest/binary>> = Bin,
     BinMsg = [MsgType, ?uint24(Len), ?uint16(MsgSeq), ?uint24(Offset), ?uint24(FragmentLen), Fragment],
-    dtls_split_handshake(Mss, MsgType, Len, MsgSeq, Rest, Offset + FragmentLen, [BinMsg|Acc]).
+    dtls_fragment(Mss, MsgType, Len, MsgSeq, Rest, Offset + FragmentLen, [BinMsg|Acc]).
 
 get_dtls_handshake_aux(#ssl_tls{version = Version,
-				record_seq = SeqNo,
-				fragment = Data}, HsState) ->
+ 				sequence_number = SeqNo,
+ 				fragment = Data}, HsState) ->
     get_dtls_handshake_aux(Version, SeqNo, Data, HsState).
 
 get_dtls_handshake_aux(Version, SeqNo,
-		       <<?BYTE(Type), ?UINT24(Length),
-			 ?UINT16(MessageSeq),
-			 ?UINT24(FragmentOffset), ?UINT24(FragmentLength),
-			 Body:FragmentLength/binary, Rest/binary>>,
-		       HsState0) ->
+ 		       <<?BYTE(Type), ?UINT24(Length),
+ 			 ?UINT16(MessageSeq),
+ 			 ?UINT24(FragmentOffset), ?UINT24(FragmentLength),
+ 			 Body:FragmentLength/binary, Rest/binary>>,
+ 		       HsState0) ->
     case reassemble_dtls_fragment(SeqNo, Type, Length, MessageSeq,
-				 FragmentOffset, FragmentLength,
-				 Body, HsState0) of
-	{retransmit, HsState1} ->
-	    case Rest of
-		<<>> ->
-		    {retransmit, HsState1};
-		_ ->
-		    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState1)
-	    end;
-	{HsState1, HighestSeqNo, MsgBody} ->
-	    HsState2 = dec_dtls_fragment(Version, HighestSeqNo, Type, Length, MessageSeq, MsgBody, HsState1),
-	    HsState3 = process_dtls_fragments(Version, HsState2),
-	    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState3);
-	HsState2 ->
-	    HsState3 = process_dtls_fragments(Version, HsState2),
-	    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState3)
-    end;
+				  FragmentOffset, FragmentLength,
+				  Body, HsState0) of
+ 	{retransmit, HsState1} ->
+ 	    case Rest of
+ 		<<>> ->
+ 		    {retransmit, HsState1};
+ 		_ ->
+ 		    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState1)
+ 	    end;
+ 	{HsState1, HighestSeqNo, MsgBody} ->
+ 	    HsState2 = dec_dtls_fragment(Version, HighestSeqNo, Type, Length, MessageSeq, MsgBody, HsState1),
+ 	    HsState3 = process_dtls_fragments(Version, HsState2),
+ 	    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState3);
+ 	HsState2 ->
+ 	    HsState3 = process_dtls_fragments(Version, HsState2),
+ 	    get_dtls_handshake_aux(Version, SeqNo, Rest, HsState3)
+     end;
 
 get_dtls_handshake_aux(_Version, _SeqNo, <<>>, HsState) ->
-    {lists:reverse(HsState#dtls_hs_state.completed),
-     HsState#dtls_hs_state{completed = []}}.
+     {lists:reverse(HsState#dtls_hs_state.completed),
+      HsState#dtls_hs_state{completed = []}}.
 
 dec_dtls_fragment(Version, SeqNo, Type, Length, MessageSeq, MsgBody,
-		  HsState = #dtls_hs_state{highest_record_seq = HighestSeqNo, completed = Acc}) ->
+ 		  HsState = #dtls_hs_state{highest_record_seq = HighestSeqNo, completed = Acc}) ->
     Raw = <<?BYTE(Type), ?UINT24(Length), ?UINT16(MessageSeq), ?UINT24(0), ?UINT24(Length), MsgBody/binary>>,
     H = decode_handshake(Version, Type, MsgBody),
     HsState#dtls_hs_state{completed = [{H,Raw}|Acc], highest_record_seq = erlang:max(HighestSeqNo, SeqNo)}.
 
 process_dtls_fragments(Version,
-		       HsState0 = #dtls_hs_state{current_read_seq = CurrentReadSeq,
-						 fragments = Fragments0}) ->
+ 		       HsState0 = #dtls_hs_state{current_read_seq = CurrentReadSeq,
+ 						 fragments = Fragments0}) ->
     case gb_trees:is_empty(Fragments0) of
-	true ->
-	    HsState0;
-	_ ->
-	    case gb_trees:smallest(Fragments0) of
-		{CurrentReadSeq, {SeqNo, Type, Length, CurrentReadSeq, {Length, [{0, Length}], MsgBody}}} ->
-		    HsState1 = dtls_hs_state_process_seq(HsState0),
-		    HsState2 = dec_dtls_fragment(Version, SeqNo, Type, Length, CurrentReadSeq, MsgBody, HsState1),
-		    process_dtls_fragments(Version, HsState2);
-		_ ->
-		    HsState0
-	    end
-    end.
+ 	true ->
+ 	    HsState0;
+ 	_ ->
+ 	    case gb_trees:smallest(Fragments0) of
+ 		{CurrentReadSeq, {SeqNo, Type, Length, CurrentReadSeq, {Length, [{0, Length}], MsgBody}}} ->
+ 		    HsState1 = dtls_hs_state_process_seq(HsState0),
+ 		    HsState2 = dec_dtls_fragment(Version, SeqNo, Type, Length, CurrentReadSeq, MsgBody, HsState1),
+ 		    process_dtls_fragments(Version, HsState2);
+ 		_ ->
+ 		    HsState0
+ 	    end
+     end.
 
 dtls_hs_state_process_seq(HsState0 = #dtls_hs_state{current_read_seq = CurrentReadSeq,
-						    fragments = Fragments0}) ->
+ 						    fragments = Fragments0}) ->
     Fragments1 = gb_trees:delete_any(CurrentReadSeq, Fragments0),
     HsState0#dtls_hs_state{current_read_seq = CurrentReadSeq + 1,
-			   fragments = Fragments1}.
+ 			   fragments = Fragments1}.
 
 dtls_hs_state_add_fragment(MessageSeq, Fragment, HsState0 = #dtls_hs_state{fragments = Fragments0}) ->
     Fragments1 = gb_trees:enter(MessageSeq, Fragment, Fragments0),
     HsState0#dtls_hs_state{fragments = Fragments1}.
 
 reassemble_dtls_fragment(SeqNo, Type, Length, MessageSeq, 0, Length,
-			 Body, HsState0 = #dtls_hs_state{current_read_seq = undefined})
+ 			 Body, HsState0 = #dtls_hs_state{current_read_seq = undefined})
   when Type == ?CLIENT_HELLO;
        Type == ?SERVER_HELLO;
-       Type == ?HELLO_VERIFY_REQUEST ->
+        Type == ?HELLO_VERIFY_REQUEST ->
     %% First message, should be client hello
     %% return the current message and set the next expected Sequence
     %%
@@ -245,8 +283,8 @@ reassemble_dtls_fragment(_SeqNo, _Type, Length, _MessageSeq, _, Length,
     HsState;
 
 reassemble_dtls_fragment(SeqNo, _Type, Length, MessageSeq, 0, Length,
-			 Body, HsState0 =
-			     #dtls_hs_state{starting_read_seq = StartingReadSeq})
+ 			 Body, HsState0 =
+ 			     #dtls_hs_state{starting_read_seq = StartingReadSeq})
   when MessageSeq < StartingReadSeq ->
     %% this has to be the start of a new flight, let it through
     %%
@@ -257,69 +295,69 @@ reassemble_dtls_fragment(SeqNo, _Type, Length, MessageSeq, 0, Length,
     {HsState, SeqNo, Body};
 
 reassemble_dtls_fragment(_SeqNo, _Type, Length, MessageSeq, 0, Length,
-			 _Body, HsState =
-			     #dtls_hs_state{current_read_seq = CurrentReadSeq})
+ 			 _Body, HsState =
+ 			     #dtls_hs_state{current_read_seq = CurrentReadSeq})
   when MessageSeq < CurrentReadSeq ->
     {retransmit, HsState};
 
 reassemble_dtls_fragment(_SeqNo, _Type, Length, MessageSeq, 0, Length,
-			 _Body, HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
+ 			 _Body, HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
   when MessageSeq < CurrentReadSeq ->
     HsState;
 
 reassemble_dtls_fragment(SeqNo, _Type, Length, MessageSeq, 0, Length,
-			 Body, HsState0 = #dtls_hs_state{current_read_seq = MessageSeq}) ->
+ 			 Body, HsState0 = #dtls_hs_state{current_read_seq = MessageSeq}) ->
     %% Message fully contained and it's the current seq
     HsState1 = dtls_hs_state_process_seq(HsState0),
     {HsState1, SeqNo, Body};
 
 reassemble_dtls_fragment(SeqNo, Type, Length, MessageSeq, 0, Length,
-			 Body, HsState) ->
+ 			 Body, HsState) ->
     %% Message fully contained and it's the NOT the current seq -> buffer
     Fragment = {SeqNo, Type, Length, MessageSeq,
-		dtls_fragment_init(Length, 0, Length, Body)},
+ 		dtls_fragment_init(Length, 0, Length, Body)},
     dtls_hs_state_add_fragment(MessageSeq, Fragment, HsState);
 
 reassemble_dtls_fragment(_SeqNo, _Type, Length, MessageSeq, FragmentOffset, FragmentLength,
-			 _Body,
-			 HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
+ 			 _Body,
+ 			 HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
   when FragmentOffset + FragmentLength == Length andalso MessageSeq == (CurrentReadSeq - 1) ->
     {retransmit, HsState};
 
 reassemble_dtls_fragment(_SeqNo, _Type, _Length, MessageSeq, _FragmentOffset, _FragmentLength,
-			 _Body,
-			 HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
+ 			 _Body,
+ 			 HsState = #dtls_hs_state{current_read_seq = CurrentReadSeq})
   when MessageSeq < CurrentReadSeq ->
     HsState;
 
 reassemble_dtls_fragment(SeqNo, Type, Length, MessageSeq,
-			 FragmentOffset, FragmentLength,
-			 Body,
-			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
+ 			 FragmentOffset, FragmentLength,
+ 			 Body,
+ 			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
     case gb_trees:lookup(MessageSeq, Fragments0) of
-	{value, Fragment} ->
-	    dtls_fragment_reassemble(SeqNo, Type, Length, MessageSeq,
-				     FragmentOffset, FragmentLength,
-				     Body, Fragment, HsState);
-	none ->
-	    dtls_fragment_start(SeqNo, Type, Length, MessageSeq,
-				FragmentOffset, FragmentLength,
-				Body, HsState)
+ 	{value, Fragment} ->
+ 	    dtls_fragment_reassemble(SeqNo, Type, Length, MessageSeq,
+ 				     FragmentOffset, FragmentLength,
+ 				     Body, Fragment, HsState);
+ 	none ->
+ 	    dtls_fragment_start(SeqNo, Type, Length, MessageSeq,
+ 				FragmentOffset, FragmentLength,
+ 				Body, HsState)
     end.
 
 dtls_fragment_start(SeqNo, Type, Length, MessageSeq,
-				FragmentOffset, FragmentLength,
-				Body, HsState = #dtls_hs_state{fragments = Fragments0}) ->
+		    FragmentOffset, FragmentLength,
+		    Body, HsState = #dtls_hs_state{fragments = Fragments0}) ->
     Fragment = {SeqNo, Type, Length, MessageSeq,
-		dtls_fragment_init(Length, FragmentOffset, FragmentLength, Body)},
-    Fragments1 = gb_trees:insert(MessageSeq, Fragment, Fragments0),
+ 		dtls_fragment_init(Length, FragmentOffset, FragmentLength, Body)},
+     Fragments1 = gb_trees:insert(MessageSeq, Fragment, Fragments0),
     HsState#dtls_hs_state{fragments = Fragments1}.
 
 dtls_fragment_reassemble(SeqNo, Type, Length, MessageSeq,
 			 FragmentOffset, FragmentLength,
-			 Body,
-			 {LastSeqNo, Type, Length, MessageSeq, FragBuffer0},
-			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
+ 			 Body,
+ 			 {LastSeqNo, Type, Length, MessageSeq, FragBuffer0},
+ 			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
     FragBuffer1 = dtls_fragment_add(FragBuffer0, FragmentOffset, FragmentLength, Body),
     Fragment = {erlang:max(SeqNo, LastSeqNo), Type, Length, MessageSeq, FragBuffer1},
     Fragments1 = gb_trees:enter(MessageSeq, Fragment, Fragments0),
@@ -328,8 +366,8 @@ dtls_fragment_reassemble(SeqNo, Type, Length, MessageSeq,
 %% Type, Length or Seq mismatch, drop everything...
 %% Note: the RFC is not clear on how to handle this...
 dtls_fragment_reassemble(_SeqNo, _Type, _Length, MessageSeq,
-			 _FragmentOffset, _FragmentLength, _Body, _Fragment,
-			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
+ 			 _FragmentOffset, _FragmentLength, _Body, _Fragment,
+ 			 HsState = #dtls_hs_state{fragments = Fragments0}) ->
     Fragments1 = gb_trees:delete_any(MessageSeq, Fragments0),
     HsState#dtls_hs_state{fragments = Fragments1}.
 
@@ -360,7 +398,7 @@ merge_fragment_list(Rest = [{HStart, _HEnd}|_], Frag = {_FStart, FEnd}, Acc)
     lists:reverse(Acc) ++ [Frag|Rest];
 
 merge_fragment_list([{HStart, HEnd}|Rest], _Frag = {FStart, FEnd}, Acc)
-  when
+   when
       FStart =< HEnd orelse FEnd >= HStart ->
     Start = erlang:min(HStart, FStart),
     End = erlang:max(HEnd, FEnd),
@@ -370,20 +408,20 @@ merge_fragment_list([{HStart, HEnd}|Rest], _Frag = {FStart, FEnd}, Acc)
 add_fragment(List, {FragmentOffset, FragmentLength}) ->
     merge_fragment_list(List, {FragmentOffset, FragmentOffset + FragmentLength}, []).
 
-enc_hs(#hello_verify_request{protocol_version = {Major, Minor},
-			     cookie = Cookie}, _Version) ->
-    CookieLength = byte_size(Cookie),
+enc_handshake(#hello_verify_request{protocol_version = {Major, Minor},
+ 				       cookie = Cookie}, _Version) ->
+     CookieLength = byte_size(Cookie),
     {?HELLO_VERIFY_REQUEST, <<?BYTE(Major), ?BYTE(Minor),
-			      ?BYTE(CookieLength),
-			      Cookie/binary>>};
-
-enc_hs(#client_hello{client_version = {Major, Minor},
-		     random = Random,
-		     session_id = SessionID,
-		     cookie = Cookie,
-		     cipher_suites = CipherSuites,
-		     compression_methods = CompMethods,
-		     extensions = HelloExtensions}, Version) ->
+ 			      ?BYTE(CookieLength),
+ 			      Cookie/binary>>};
+
+enc_handshake(#client_hello{client_version = {Major, Minor},
+			       random = Random,
+			       session_id = SessionID,
+			       cookie = Cookie,
+			       cipher_suites = CipherSuites,
+			       compression_methods = CompMethods,
+			       extensions = HelloExtensions}, Version) ->
     SIDLength = byte_size(SessionID),
     BinCookie = enc_client_hello_cookie(Version, Cookie),
     BinCompMethods = list_to_binary(CompMethods),
@@ -391,13 +429,13 @@ enc_hs(#client_hello{client_version = {Major, Minor},
     BinCipherSuites = list_to_binary(CipherSuites),
     CsLength = byte_size(BinCipherSuites),
     ExtensionsBin = ssl_handshake:encode_hello_extensions(HelloExtensions),
-
+    
     {?CLIENT_HELLO, <<?BYTE(Major), ?BYTE(Minor), Random:32/binary,
-		      ?BYTE(SIDLength), SessionID/binary,
-		      BinCookie/binary,
-				?UINT16(CsLength), BinCipherSuites/binary,
-		      ?BYTE(CmLength), BinCompMethods/binary, ExtensionsBin/binary>>};
-enc_hs(HandshakeMsg, Version) ->
+ 		      ?BYTE(SIDLength), SessionID/binary,
+ 		      BinCookie/binary,
+		      ?UINT16(CsLength), BinCipherSuites/binary,
+ 		      ?BYTE(CmLength), BinCompMethods/binary, ExtensionsBin/binary>>};
+enc_handshake(HandshakeMsg, Version) ->
     ssl_handshake:encode_handshake(HandshakeMsg, Version).
 
 enc_client_hello_cookie(_, <<>>) ->
@@ -407,26 +445,26 @@ enc_client_hello_cookie(_, Cookie) ->
     <<?BYTE(CookieLength), Cookie/binary>>.
 
 decode_handshake(_Version, ?CLIENT_HELLO, <<?BYTE(Major), ?BYTE(Minor), Random:32/binary,
-		       ?BYTE(SID_length), Session_ID:SID_length/binary,
-		       ?BYTE(Cookie_length), Cookie:Cookie_length/binary,
-		       ?UINT16(Cs_length), CipherSuites:Cs_length/binary,
-		       ?BYTE(Cm_length), Comp_methods:Cm_length/binary,
-		       Extensions/binary>>) ->
-
+					    ?BYTE(SID_length), Session_ID:SID_length/binary,
+					    ?BYTE(Cookie_length), Cookie:Cookie_length/binary,
+					    ?UINT16(Cs_length), CipherSuites:Cs_length/binary,
+					    ?BYTE(Cm_length), Comp_methods:Cm_length/binary,
+					    Extensions/binary>>) ->
+    
     DecodedExtensions = ssl_handshake:decode_hello_extensions(Extensions),
-
+    
     #client_hello{
        client_version = {Major,Minor},
        random = Random,
-       session_id = Session_ID,
+        session_id = Session_ID,
        cookie = Cookie,
        cipher_suites = ssl_handshake:decode_suites('2_bytes', CipherSuites),
        compression_methods = Comp_methods,
        extensions = DecodedExtensions
-      };
+       };
 
 decode_handshake(_Version, ?HELLO_VERIFY_REQUEST, <<?BYTE(Major), ?BYTE(Minor),
-					  ?BYTE(CookieLength), Cookie:CookieLength/binary>>) ->
+						    ?BYTE(CookieLength), Cookie:CookieLength/binary>>) ->
 
     #hello_verify_request{
        protocol_version = {Major,Minor},
@@ -434,7 +472,7 @@ decode_handshake(_Version, ?HELLO_VERIFY_REQUEST, <<?BYTE(Major), ?BYTE(Minor),
 decode_handshake(Version, Tag, Msg) ->
     ssl_handshake:decode_handshake(Version, Tag, Msg).
 
-address_to_bin({A,B,C,D}, Port) ->
-    <<0:80,16#ffff:16,A,B,C,D,Port:16>>;
-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>>.
+%% address_to_bin({A,B,C,D}, Port) ->
+%%     <<0:80,16#ffff:16,A,B,C,D,Port:16>>;
+%% 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>>.