aboutsummaryrefslogblamecommitdiffstats
path: root/lib/ssl/src/ssl_connection.erl
blob: bbffa1e564890f68584a4da69847935048713754 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612

                   


                                                        




                                                                      
  



                                                                         
  



















































































































































































































































































































































































































































































































































































































                                                                                                         
                                            






                                                                     









                                                                                  





























































































































































































































































































































































                                                                                                




                                                                       
                          

                                                                       















                                                                  











                                                                                       









                                                                                  








                                                                                     



























                                                          
                                                               











































































                                                                             





                                                                                   


























































































































































































































































































                                                                               
















                                                                       








































































































































































































































































































                                                                                 
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2007-2010. 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: Handles an ssl connection, e.i. both the setup
%% e.i. SSL-Handshake, SSL-Alert and SSL-Cipher protocols and delivering
%% data to the application. All data on the connectinon is received and 
%% sent according to the SSL-record protocol.  
%%----------------------------------------------------------------------

-module(ssl_connection).

-behaviour(gen_fsm).

-include("ssl_debug.hrl").
-include("ssl_handshake.hrl").
-include("ssl_alert.hrl").
-include("ssl_record.hrl").
-include("ssl_cipher.hrl"). 
-include("ssl_internal.hrl").
-include("ssl_int.hrl").
-include_lib("public_key/include/public_key.hrl"). 

%% Internal application API
-export([send/2, send/3, recv/3, connect/7, accept/6, close/1, shutdown/2,
	 new_user/2, get_opts/2, set_opts/2, info/1, session_info/1, 
	 peer_certificate/1,
	 sockname/1, peername/1]).

%% Called by ssl_connection_sup
-export([start_link/7]). 

%% gen_fsm callbacks
-export([init/1, hello/2, certify/2, cipher/2, connection/2, connection/3, abbreviated/2,
         handle_event/3,
         handle_sync_event/4, handle_info/3, terminate/3, code_change/4]).

-record(state, {
          role,               % client | server
          user_application,   % {MonitorRef, pid()} 
          transport_cb,       % atom() - callback module 
          data_tag,           % atom()  - ex tcp.
	  close_tag,          % atom()  - ex tcp_closed
          host,               % string() | ipadress()
          port,               % integer()
          socket,             % socket() 
          ssl_options,        % #ssl_options{}
          socket_options,     % #socket_options{}
          connection_states,  % #connection_states{} from ssl_record.hrl
          tls_record_buffer,  % binary() buffer of incomplete records
          tls_handshake_buffer, % binary() buffer of incomplete handshakes
	  %% {{md5_hash, sha_hash}, {prev_md5, prev_sha}} (binary())
          tls_handshake_hashes, % see above 
          tls_cipher_texts,     % list() received but not deciphered yet
          own_cert,             % binary()  
          session,              % #session{} from ssl_handshake.erl
	  session_cache,        % 
	  session_cache_cb,     %
          negotiated_version,   % #protocol_version{}
          supported_protocol_versions, % [atom()]
          client_certificate_requested = false,
	  key_algorithm,       % atom as defined by cipher_suite
          public_key_info,     % PKIX: {Algorithm, PublicKey, PublicKeyParams}
          private_key,         % PKIX: 'RSAPrivateKey'
	  diffie_hellman_params, % 
          premaster_secret,    %
          cert_db_ref,         % ets_table()
          from,                % term(), where to reply
          bytes_to_read,       % integer(), # bytes to read in passive mode
          user_data_buffer,    % binary()
%%	  tls_buffer,          % Keeps a lookahead one packet if available
	  log_alert            % boolan() 
	 }).

%%====================================================================
%% Internal application API
%%====================================================================	     

%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
send(Pid, Data) -> 
    sync_send_event(Pid, {application_data, erlang:iolist_to_binary(Data)}, infinity).
send(Pid, Data, Timeout) -> 
    sync_send_event(Pid, {application_data, erlang:iolist_to_binary(Data)}, Timeout).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
recv(Pid, Length, Timeout) -> % TODO: Prio with renegotiate? 
    sync_send_all_state_event(Pid, {recv, Length}, Timeout).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
connect(Host, Port, Socket, Options, User, CbInfo, Timeout) ->
    start_fsm(client, Host, Port, Socket, Options, User, CbInfo,
	      Timeout).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
accept(Port, Socket, Opts, User, CbInfo, Timeout) ->
    start_fsm(server, "localhost", Port, Socket, Opts, User, 
	      CbInfo, Timeout).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
close(ConnectionPid) ->
    case sync_send_all_state_event(ConnectionPid, close) of
	{error, closed} ->
	    ok;
	Other ->
	    Other
    end.

%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
shutdown(ConnectionPid, How) ->
    sync_send_all_state_event(ConnectionPid, {shutdown, How}).


%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
new_user(ConnectionPid, User) ->
    sync_send_all_state_event(ConnectionPid, {new_user, User}).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
sockname(ConnectionPid) ->
    sync_send_all_state_event(ConnectionPid, sockname).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
peername(ConnectionPid) ->
    sync_send_all_state_event(ConnectionPid, peername).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
get_opts({ListenSocket, {_SslOpts, SockOpts}, _}, OptTags) ->
    get_socket_opts(ListenSocket, OptTags, SockOpts, []);
get_opts(ConnectionPid, OptTags) ->
    sync_send_all_state_event(ConnectionPid, {get_opts, OptTags}).
%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
set_opts(ConnectionPid, Options) ->
    sync_send_all_state_event(ConnectionPid, {set_opts, Options}).

%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
info(ConnectionPid) ->
    sync_send_all_state_event(ConnectionPid, info). 

%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
session_info(ConnectionPid) ->
    sync_send_all_state_event(ConnectionPid, session_info). 

%%--------------------------------------------------------------------
%% Function: 
%%
%% Description: 
%%--------------------------------------------------------------------
peer_certificate(ConnectionPid) ->
    sync_send_all_state_event(ConnectionPid, peer_certificate). 

%%====================================================================
%% ssl_connection_sup API
%%====================================================================

%%--------------------------------------------------------------------
%% Function: start_link() -> {ok,Pid} | ignore | {error,Error}
%%
%% Description: Creates a gen_fsm process which calls Module:init/1 to
%% initialize. To ensure a synchronized start-up procedure, this function
%% does not return until Module:init/1 has returned.  
%%--------------------------------------------------------------------
start_link(Role, Host, Port, Socket, Options, User, CbInfo) ->
    gen_fsm:start_link(?MODULE, [Role, Host, Port, Socket, Options,
				 User, CbInfo], []).


%%====================================================================
%% gen_fsm callbacks
%%====================================================================
%%--------------------------------------------------------------------
%% Function: init(Args) -> {ok, StateName, State} |
%%                         {ok, StateName, State, Timeout} |
%%                         ignore                              |
%%                         {stop, StopReason}                   
%% Description:Whenever a gen_fsm is started using gen_fsm:start/[3,4] or
%% gen_fsm:start_link/3,4, this function is called by the new process to 
%% initialize. 
%%--------------------------------------------------------------------
init([Role, Host, Port, Socket, {SSLOpts, _} = Options, 
      User, CbInfo]) ->
    State0 = initial_state(Role, Host, Port, Socket, Options, User, CbInfo),
    Hashes0 = ssl_handshake:init_hashes(),    

    try ssl_init(SSLOpts, Role) of
	{ok, Ref, CacheRef, OwnCert, Key} ->	   
	    State = State0#state{tls_handshake_hashes = Hashes0,
				 own_cert = OwnCert,
				 cert_db_ref = Ref,
				 session_cache = CacheRef,
				 private_key = Key},
	    {ok, hello, State}
    catch   
	throw:Error ->
	    {stop, Error}
    end.
  
%%--------------------------------------------------------------------
%% Function: 
%% state_name(Event, State) -> {next_state, NextStateName, NextState}|
%%                             {next_state, NextStateName, 
%%                                NextState, Timeout} |
%%                             {stop, Reason, NewState}
%% Description:There should be one instance of this function for each possible
%% state name. Whenever a gen_fsm receives an event sent using
%% gen_fsm:send_event/2, the instance of this function with the same name as
%% the current state name StateName is called to handle the event. It is also 
%% called if a timeout occurs. 
%%--------------------------------------------------------------------
hello(socket_control, #state{host = Host, port = Port, role = client,
			     ssl_options = SslOpts, 
			     transport_cb = Transport, socket = Socket,
			     connection_states = ConnectionStates}
      = State0) ->
    Hello = ssl_handshake:client_hello(Host, Port, ConnectionStates, SslOpts),
    Version = Hello#client_hello.client_version,
    Hashes0 = ssl_handshake:init_hashes(),
    {BinMsg, CS2, Hashes1} = 
        encode_handshake(Hello, Version, ConnectionStates, Hashes0),
    Transport:send(Socket, BinMsg),
    State = State0#state{connection_states = CS2,
			 negotiated_version = Version, %% Requested version
			 session = 
                         #session{session_id = Hello#client_hello.session_id,
                                  is_resumable = false},
                         tls_handshake_hashes = Hashes1},
    {next_state, hello, next_record(State)};
    
hello(socket_control, #state{role = server} = State) ->
    {next_state, hello, next_record(State)};

hello(hello, #state{role = client} = State) ->
    {next_state, hello, State};

hello(#server_hello{cipher_suite = CipherSuite,
		    compression_method = Compression} = Hello,
      #state{session = Session0 = #session{session_id = OldId},
	     connection_states = ConnectionStates0,
	     role = client,
	     negotiated_version = ReqVersion,
	     host = Host, port = Port,
	     session_cache = Cache,
	     session_cache_cb = CacheCb} = State0) ->
    {Version, NewId, ConnectionStates1} =
        ssl_handshake:hello(Hello, ConnectionStates0),

    {KeyAlgorithm, _, _, _} = 
        ssl_cipher:suite_definition(CipherSuite),
    
    PremasterSecret = make_premaster_secret(ReqVersion),
    
    State = State0#state{key_algorithm = KeyAlgorithm,
			 negotiated_version = Version,
			 connection_states = ConnectionStates1,
			 premaster_secret = PremasterSecret},

    case ssl_session:is_new(OldId, NewId) of
        true ->
	    Session = Session0#session{session_id = NewId,
				       cipher_suite = CipherSuite,
				       compression_method = Compression}, 
            {next_state, certify, 
             next_record(State#state{session = Session})};
        false ->
	    Session = CacheCb:lookup(Cache, {{Host, Port}, NewId}),
	    case ssl_handshake:master_secret(Version, Session, 
					     ConnectionStates1, client) of
		{_, ConnectionStates2} ->	
		    {next_state, abbreviated,
		     next_record(State#state{
				   connection_states = ConnectionStates2,
				   session = Session})};
		#alert{} = Alert ->
		    handle_own_alert(Alert, Version, hello, State), 
		    {stop, normal, State}
	    end
    end;

hello(Hello = #client_hello{client_version = ClientVersion}, 
      State = #state{connection_states = ConnectionStates0,
		     port = Port, session = Session0,
		     session_cache = Cache,
		     session_cache_cb = CacheCb,
		     ssl_options = SslOpts}) ->
    
    case ssl_handshake:hello(Hello, {Port, SslOpts,  
				     Session0, Cache, CacheCb,
				     ConnectionStates0}) of
        {Version, {Type, Session}, ConnectionStates} ->       
            do_server_hello(Type, State#state{connection_states  = 
					      ConnectionStates,
					      negotiated_version = Version,
					      session = Session});
        #alert{} = Alert ->
            handle_own_alert(Alert, ClientVersion, hello, State), 
            {stop, normal, State}
    end.

abbreviated(socket_control, #state{role = server} = State) ->
    {next_state, abbreviated, State};
abbreviated(hello, State) ->
    {next_state, certify, State};

abbreviated(Finished = #finished{},
	    #state{role = server,
		   negotiated_version = Version,
		   tls_handshake_hashes = Hashes,
		   session = #session{master_secret = MasterSecret},
		   from = From} = State) ->
    case ssl_handshake:verify_connection(Version, Finished, client,
					 MasterSecret, Hashes) of
        verified ->
            gen_fsm:reply(From, connected),
	    {next_state, connection, next_record_if_active(State)};
        #alert{} = Alert ->
	    handle_own_alert(Alert, Version, abbreviated, State),
            {stop, normal, State} 
    end;

abbreviated(Finished = #finished{},
	    #state{role = client, tls_handshake_hashes = Hashes0,
		   session = #session{master_secret = MasterSecret},
		   from = From,
		   negotiated_version = Version} = State) ->
    case ssl_handshake:verify_connection(Version, Finished, server,
					 MasterSecret, Hashes0) of
        verified ->
	    {ConnectionStates, Hashes} = finalize_client_handshake(State),
            gen_fsm:reply(From, connected),
	    {next_state, connection,
	     next_record_if_active(State#state{tls_handshake_hashes = Hashes,
					       connection_states = 
					       ConnectionStates})};
        #alert{} = Alert ->
	    handle_own_alert(Alert, Version, abbreviated, State),
            {stop, normal, State} 
    end.

certify(socket_control, #state{role = server} = State) ->
    {next_state, certify, State};
certify(hello, State) ->
    {next_state, certify, State};

certify(#certificate{asn1_certificates = []}, 
	#state{role = server, negotiated_version = Version,
	       ssl_options = #ssl_options{verify = verify_peer,
					  fail_if_no_peer_cert = true}} = 
	State) ->
    Alert =  ?ALERT_REC(?FATAL,?HANDSHAKE_FAILURE),
    handle_own_alert(Alert, Version, certify_certificate, State),
    {stop, normal, State};

certify(#certificate{asn1_certificates = []}, 
	#state{role = server,
	       ssl_options = #ssl_options{verify = verify_peer,
					  fail_if_no_peer_cert = false}} = 
	State) ->
    {next_state, certify, next_record(State#state{client_certificate_requested = false})};

certify(#certificate{} = Cert, 
        #state{session = Session, 
	       negotiated_version = Version,
	       cert_db_ref = CertDbRef,
	       ssl_options = Opts} = State0) ->
    case ssl_handshake:certify(Cert, CertDbRef, Opts#ssl_options.depth, 
			       Opts#ssl_options.verify,
			       Opts#ssl_options.verify_fun) of
        {PeerCert, PublicKeyInfo} ->
            State = State0#state{session = 
                                 Session#session{peer_certificate = PeerCert},				 
                                 public_key_info = PublicKeyInfo,
				 client_certificate_requested = false
				},
            {next_state, certify, next_record(State)};
	#alert{} = Alert ->
            handle_own_alert(Alert, Version, certify_certificate, State0),
            {stop, normal, State0}
    end;

certify(#server_key_exchange{} = KeyExchangeMsg, 
        #state{role = client,
	       key_algorithm = Alg} = State) 
  when Alg == dhe_dss; Alg == dhe_rsa; Alg == dh_anon; Alg == krb5 ->
    NewState = handle_server_key(KeyExchangeMsg, State),
    {next_state, certify, NewState};

certify(#server_key_exchange{}, 
        State = #state{role = client, negotiated_version = Version,
                       key_algorithm = Alg}) 
  when Alg == rsa; Alg == dh_dss; Alg == dh_rsa ->
    Alert = ?ALERT_REC(?FATAL, ?UNEXPECTED_MESSAGE),
    handle_own_alert(Alert, Version, certify_server_key_exchange, State),
    {stop, normal, State};

certify(KeyExchangeMsg = #server_key_exchange{}, State = 
        #state{role = server}) ->
    NewState = handle_clinet_key(KeyExchangeMsg, State),
    {next_state, cipher, NewState};

certify(#certificate_request{}, State) ->
    NewState = State#state{client_certificate_requested = true},
    {next_state, certify, next_record(NewState)};

certify(#server_hello_done{},
	#state{session = Session0,
	       connection_states = ConnectionStates0,
	       negotiated_version = Version,
	       premaster_secret = PremasterSecret,
	       role = client} = State0) ->    
    case ssl_handshake:master_secret(Version, PremasterSecret, 
				     ConnectionStates0, client) of
	{MasterSecret, ConnectionStates1} -> 
	    Session = Session0#session{master_secret = MasterSecret},
	    State = State0#state{connection_states = ConnectionStates1,
				  session = Session},
	    client_certify_and_key_exchange(State);
	#alert{} = Alert ->
	    handle_own_alert(Alert, Version, 
			     certify_server_hello_done, State0),
	    {stop, normal, State0} 
    end;

certify(#client_key_exchange{},
	State = #state{role = server,
		       client_certificate_requested = true,
		       ssl_options = #ssl_options{fail_if_no_peer_cert = true},
		       negotiated_version = Version}) ->
    %% We expect a certificate here
    Alert = ?ALERT_REC(?FATAL, ?UNEXPECTED_MESSAGE),
    handle_own_alert(Alert, Version, certify_server_waiting_certificate, State),
    {stop, normal, State};


certify(#client_key_exchange{exchange_keys 
			     = #encrypted_premaster_secret{premaster_secret 
							   = EncPMS}},
        #state{negotiated_version = Version,
	       connection_states = ConnectionStates0,
	       session = Session0,
	       private_key = Key} = State0) ->
    try ssl_handshake:decrypt_premaster_secret(EncPMS, Key) of
	PremasterSecret ->
	    case ssl_handshake:master_secret(Version, PremasterSecret, 
					     ConnectionStates0, server) of
		{MasterSecret, ConnectionStates} ->
		    Session = Session0#session{master_secret = MasterSecret},
		    State = State0#state{connection_states = ConnectionStates,
					 session = Session},
		    {next_state, cipher, next_record(State)};
		#alert{} = Alert ->
		    handle_own_alert(Alert, Version, 
				     certify_client_key_exchange, State0),
		    {stop, normal, State0} 
	    end
    catch 
	#alert{} = Alert ->
	    handle_own_alert(Alert, Version, certify_client_key_exchange, 
			     State0),
	    {stop, normal, State0} 
    end.

cipher(socket_control, #state{role = server} = State) ->
    {next_state, cipher, State};
cipher(hello, State) ->
    {next_state, cipher, State};

cipher(#certificate_verify{signature = Signature}, 
       #state{role = server, 
	      public_key_info = PublicKeyInfo,
	      negotiated_version = Version,
	      session = #session{master_secret = MasterSecret},
	      key_algorithm = Algorithm,
	      tls_handshake_hashes = Hashes
	     } = State) -> 
    case ssl_handshake:certificate_verify(Signature, PublicKeyInfo,
					  Version, MasterSecret, 
					  Algorithm, Hashes) of
	valid ->
	    {next_state, cipher, next_record(State)};
	#alert{} = Alert ->
	    handle_own_alert(Alert, Version, cipher, State), 
	    {stop, normal, State}
    end;

cipher(#finished{} = Finished, 
       State = #state{from = From,
                      negotiated_version = Version,
		      host = Host,
		      port = Port,
		      role = Role,
		      session = #session{master_secret = MasterSecret} 
		      = Session0,
                      tls_handshake_hashes = Hashes}) ->    

    case ssl_handshake:verify_connection(Version, Finished, 
					 opposite_role(Role), 
                                         MasterSecret, Hashes) of
        verified ->
            gen_fsm:reply(From, connected),
	    Session = register_session(Role, Host, Port, Session0),
            case Role of
                client ->
                    {next_state, connection, 
		     next_record_if_active(State#state{session = Session})};
                server ->
                    {NewConnectionStates, NewHashes} = 
                        finalize_server_handshake(State#state{
						    session = Session}),
                    NewState = 
                        State#state{connection_states = NewConnectionStates,
				    session = Session,
                                    tls_handshake_hashes = NewHashes},
                    {next_state, connection, next_record_if_active(NewState)}
            end;
        #alert{} = Alert ->
	    handle_own_alert(Alert, Version, cipher, State),
            {stop, normal, State} 
    end.

connection(socket_control, #state{role = server} = State) ->
    {next_state, connection, State};
connection(hello, State = #state{host = Host, port = Port,
                                 socket = Socket,
				 ssl_options = SslOpts,
                                 negotiated_version = Version,
                                 transport_cb = Transport,
                                 connection_states = ConnectionStates0,
                                 tls_handshake_hashes = Hashes0}) ->

    Hello = ssl_handshake:client_hello(Host, Port, 
				       ConnectionStates0, SslOpts),
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Hello, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    {next_state, hello, State#state{connection_states = ConnectionStates1,
                                    tls_handshake_hashes = Hashes1}}.

%%--------------------------------------------------------------------
%% Function:
%% state_name(Event, From, State) -> {next_state, NextStateName, NextState} |
%%                                   {next_state, NextStateName, 
%%                                     NextState, Timeout} |
%%                                   {reply, Reply, NextStateName, NextState}|
%%                                   {reply, Reply, NextStateName, 
%%                                    NextState, Timeout} |
%%                                   {stop, Reason, NewState}|
%%                                   {stop, Reason, Reply, NewState}
%% Description: There should be one instance of this function for each
%% possible state name. Whenever a gen_fsm receives an event sent using
%% gen_fsm:sync_send_event/2,3, the instance of this function with the same
%% name as the current state name StateName is called to handle the event.
%%--------------------------------------------------------------------
connection({application_data, Data0}, _From,
           State = #state{socket = Socket,
                          negotiated_version = Version,
                          transport_cb = Transport,
                          connection_states = ConnectionStates0}) ->
    %% We should look into having a worker process to do this to 
    %% parallize send and receive decoding and not block the receiver
    %% if sending is overloading the socket.
    try
	Data = encode_packet(Data0, State#state.socket_options),
	{Msgs, ConnectionStates1} = encode_data(Data, Version, ConnectionStates0),
	Result = Transport:send(Socket, Msgs),
	{reply, Result,
	 connection, State#state{connection_states = ConnectionStates1}}

    catch throw:Error ->
	    {reply, Error, connection, State}
    end.

%%--------------------------------------------------------------------
%% Function: 
%% handle_event(Event, StateName, State) -> {next_state, NextStateName, 
%%                                                  NextState} |
%%                                          {next_state, NextStateName, 
%%                                                  NextState, Timeout} |
%%                                          {stop, Reason, NewState}
%% Description: Whenever a gen_fsm receives an event sent using
%% gen_fsm:send_all_state_event/2, this function is called to handle
%% the event.
%%--------------------------------------------------------------------
handle_event(#ssl_tls{type = ?HANDSHAKE, fragment = Data},
	     StateName,
	     State = #state{key_algorithm = KeyAlg,
			    tls_handshake_buffer = Buf0,
			    negotiated_version = Version}) ->
    Handle = 
	fun({Packet, Raw}, {next_state, SName, AS=#state{tls_handshake_hashes=Hs0}}) ->		
		Hs1 = ssl_handshake:update_hashes(Hs0, Raw),
		?MODULE:SName(Packet, AS#state{tls_handshake_hashes=Hs1});
	   (_, StopState) -> StopState
	end,
    try
	{Packets, Buf} = ssl_handshake:get_tls_handshake(Data,Buf0, KeyAlg,Version),
	Start = {next_state, StateName, State#state{tls_handshake_buffer = Buf}},
	lists:foldl(Handle, Start, Packets)
    catch throw:#alert{} = Alert ->
	    handle_own_alert(Alert, Version, StateName, State), 
	    {stop, normal, State}
    end;

handle_event(#ssl_tls{type = ?APPLICATION_DATA, fragment = Data},
             StateName, State0) ->
    case application_data(Data, State0) of
	Stop = {stop,_,_} ->
	    Stop;
	State ->
	    {next_state, StateName, State}
    end;

handle_event(#ssl_tls{type = ?CHANGE_CIPHER_SPEC, fragment = <<1>>} = 
	     _ChangeCipher,
             StateName, 
	     State = #state{connection_states = ConnectionStates0}) ->
    ?DBG_TERM(_ChangeCipher),
    ConnectionStates1 =
        ssl_record:activate_pending_connection_state(ConnectionStates0, read),
    {next_state, StateName, 
     next_record(State#state{connection_states = ConnectionStates1})};

handle_event(#ssl_tls{type = ?ALERT, fragment = Data}, StateName, State) ->
    Alerts = decode_alerts(Data),
    ?DBG_TERM(Alerts),
    [alert_event(A) || A <- Alerts],
    {next_state, StateName, State};

handle_event(#alert{level = ?FATAL} = Alert, connection, 
	     #state{from = From, user_application = {_Mon, Pid}, log_alert = Log,
		    host = Host, port = Port, session = Session,
		    role = Role, socket_options = Opts} = State) ->
    invalidate_session(Role, Host, Port, Session),
    log_alert(Log, connection, Alert),
    alert_user(Opts#socket_options.active, Pid, From, Alert, Role),
    {stop, normal, State};
handle_event(#alert{level = ?WARNING, description = ?CLOSE_NOTIFY} = Alert, 
	     connection, #state{from = From,
				role = Role,
				user_application = {_Mon, Pid}, 
				socket_options = Opts} = State) ->
    alert_user(Opts#socket_options.active, Pid, From, Alert, Role),
    {stop, normal, State};

handle_event(#alert{level = ?FATAL} = Alert, StateName,
	     #state{from = From, host = Host, port = Port, session = Session,
		    log_alert = Log, role = Role} = State) ->
    invalidate_session(Role, Host, Port, Session),
    log_alert(Log, StateName, Alert),
    alert_user(From, Alert, Role),
    {stop, normal, State};
handle_event(#alert{level = ?WARNING, description = ?CLOSE_NOTIFY} = Alert, 
	     _, #state{from = From, role = Role} = State) -> 
    alert_user(From, Alert, Role),
    {stop, normal, State};
handle_event(#alert{level = ?WARNING} = Alert, StateName, 
	     #state{log_alert = Log} = State) ->
    log_alert(Log, StateName, Alert),
%%TODO:  Could be user_canceled or no_negotiation should the latter be 
    %% treated as fatal?! 
    {next_state, StateName, next_record(State)}.

%%--------------------------------------------------------------------
%% Function: 
%% handle_sync_event(Event, From, StateName, 
%%                   State) -> {next_state, NextStateName, NextState} |
%%                             {next_state, NextStateName, NextState, 
%%                              Timeout} |
%%                             {reply, Reply, NextStateName, NextState}|
%%                             {reply, Reply, NextStateName, NextState, 
%%                              Timeout} |
%%                             {stop, Reason, NewState} |
%%                             {stop, Reason, Reply, NewState}
%% Description: Whenever a gen_fsm receives an event sent using
%% gen_fsm:sync_send_all_state_event/2,3, this function is called to handle
%% the event.
%%--------------------------------------------------------------------
handle_sync_event(started, From, StateName, State) ->
    {next_state, StateName, State#state{from = From}};

handle_sync_event(close, From, _StateName, State) ->
    {stop, normal, ok, State#state{from = From}};

handle_sync_event({shutdown, How}, From, StateName,
		  #state{transport_cb = CbModule,
			 socket = Socket} = State) ->
    case CbModule:shutdown(Socket, How) of
	ok ->
	    {reply, ok, StateName, State};
	Error ->
	    {stop, normal, Error, State#state{from = From}}
    end;
    
%% TODO: men vad g�r next_record om det �r t.ex. renegotiate? kanske
%% inte bra... t�l att t�nkas p�!
handle_sync_event({recv, N}, From, StateName,
		  State0 = #state{user_data_buffer = Buffer}) ->
    State1 = State0#state{bytes_to_read = N, from = From},
    case Buffer of
	<<>> ->
	    State = next_record(State1),
	    {next_state, StateName, State};
	_ ->
	    case application_data(<<>>, State1) of
		Stop = {stop, _, _} ->
		    Stop;
		State ->
		    {next_state, StateName, State}
	    end
    end;

handle_sync_event({new_user, User}, _From, StateName, 
		  State =#state{user_application = {OldMon, _}}) ->
    NewMon = erlang:monitor(process, User),
    erlang:demonitor(OldMon, [flush]),
    {reply, ok, StateName, State#state{user_application = {NewMon,User}}};

handle_sync_event({get_opts, OptTags}, _From, StateName,
		  #state{socket = Socket,
			 socket_options = SockOpts} = State) ->
    OptsReply = get_socket_opts(Socket, OptTags, SockOpts, []),
    {reply, OptsReply, StateName, State};

handle_sync_event(sockname, _From, StateName,
		  #state{socket = Socket} = State) ->
    SockNameReply = inet:sockname(Socket),
    {reply, SockNameReply, StateName, State};

handle_sync_event(peername, _From, StateName,
		  #state{socket = Socket} = State) ->
    PeerNameReply = inet:peername(Socket),
    {reply, PeerNameReply, StateName, State};

handle_sync_event({set_opts, Opts0}, _From, StateName, 
		  #state{socket_options = Opts1, 
			 socket = Socket,
			 user_data_buffer = Buffer} = State0) ->
    Opts   = set_socket_opts(Socket, Opts0, Opts1, []),
    State1 = State0#state{socket_options = Opts},
    if 
	Opts#socket_options.active =:= false ->
	    {reply, ok, StateName, State1};
	Buffer =:= <<>>, Opts1#socket_options.active =:= false ->
            %% Need data, set active once
	    {reply, ok, StateName, next_record_if_active(State1)};
	Buffer =:= <<>> ->
            %% Active once already set 
	    {reply, ok, StateName, State1};
	true ->
	    case application_data(<<>>, State1) of
		Stop = {stop,_,_} ->
		    Stop;
		State ->
		    {reply, ok, StateName, State}
	    end
    end;	

handle_sync_event(info, _, StateName, 
		  #state{negotiated_version = Version,
			 session = #session{cipher_suite = Suite}} = State) ->
    
    AtomVersion = ssl_record:protocol_version(Version),
    {reply, {ok, {AtomVersion, ssl_cipher:suite_definition(Suite)}}, 
     StateName, State};

handle_sync_event(session_info, _, StateName, 
		  #state{session = #session{session_id = Id,
					    cipher_suite = Suite}} = State) ->
    {reply, [{session_id, Id}, 
	     {cipher_suite, ssl_cipher:suite_definition(Suite)}], 
     StateName, State};

handle_sync_event(peer_certificate, _, StateName, 
		  #state{session = #session{peer_certificate = Cert}} 
		  = State) ->
    {reply, {ok, Cert}, StateName, State}.


%%--------------------------------------------------------------------
%% Function: 
%% handle_info(Info,StateName,State)-> {next_state, NextStateName, NextState}|
%%                                     {next_state, NextStateName, NextState, 
%%                                       Timeout} |
%%                                     {stop, Reason, NewState}
%% Description: This function is called by a gen_fsm when it receives any
%% other message than a synchronous or asynchronous event
%% (or a system message).
%%--------------------------------------------------------------------

%% raw data from TCP, unpack records
handle_info({Protocol, _, Data}, StateName, State =
            #state{data_tag = Protocol,
		   negotiated_version = Version,
                   tls_record_buffer = Buf0,
                   tls_cipher_texts = CT0}) ->
    case ssl_record:get_tls_records(Data, Buf0) of
	{Records, Buf1} ->
	    CT1 = CT0 ++ Records,
	    {next_state, StateName, 
	     next_record(State#state{tls_record_buffer = Buf1,
				     tls_cipher_texts = CT1})};
	#alert{} = Alert ->
	    handle_own_alert(Alert, Version, StateName, State), 
	    {stop, normal, State}
    end;

%% %% This is the code for {packet,ssl} removed because it was slower 
%% %% than handling it in erlang.
%% handle_info(Data = #ssl_tls{}, StateName, 
%% 	    State = #state{tls_buffer = Buffer,
%% 			   socket = Socket,
%% 			   connection_states = ConnectionStates0}) ->
%%     case Buffer of
%% 	buffer ->
%% 	    {next_state, StateName, State#state{tls_buffer = [Data]}};
%% 	continue ->
%% 	    inet:setopts(Socket, [{active,once}]),
%% 	    {Plain, ConnectionStates} =
%% 		ssl_record:decode_cipher_text(Data, ConnectionStates0),
%% 	    gen_fsm:send_all_state_event(self(), Plain),
%% 	    {next_state, StateName, 
%% 	     State#state{tls_buffer = buffer, 
%% 			 connection_states = ConnectionStates}};
%% 	List when is_list(List) ->
%% 	    {next_state, StateName, 
%% 	     State#state{tls_buffer = Buffer ++ [Data]}}	
%%     end;

%% handle_info(CloseMsg = {_, Socket}, StateName0, 
%% 	    #state{socket = Socket,tls_buffer = [Msg]} = State0) ->
%%     %% Hmm we have a ssl_tls msg buffered, handle that first
%%     %% and it proberbly is a close alert  
%%     {next_state, StateName0, State0#state{tls_buffer=[Msg,{ssl_close,CloseMsg}]}};
	
handle_info({CloseTag, Socket}, _StateName,
            #state{socket = Socket, close_tag = CloseTag,
		   negotiated_version = Version, host = Host,
		   port = Port, socket_options = Opts, 
		   user_application = {_Mon,Pid}, from = From, 
		   role = Role, session = Session} = State) ->
    %% Debug option maybe, the user do NOT want to see these in their logs
    %% error_logger:info_report("SSL: Peer did not send close notify alert."),
    case Version of
	{1, N} when N >= 1 ->
	    ok;
	_ ->
	    invalidate_session(Role, Host, Port, Session)
    end,
    alert_user(Opts#socket_options.active, Pid, From,
	       ?ALERT_REC(?WARNING, ?CLOSE_NOTIFY), Role),
    {stop, normal, State};

handle_info({'DOWN', MonitorRef, _, _, _}, _, 
	    State = #state{user_application={MonitorRef,_Pid}}) ->
    {stop, normal, State};   

handle_info(A, StateName, State) ->
    io:format("SSL: Bad info (state ~w): ~w\n", [StateName, A]),
    {stop, bad_info, State}.

%%--------------------------------------------------------------------
%% Function: terminate(Reason, StateName, State) -> void()
%% Description:This function is called by a gen_fsm when it is about
%% to terminate. It should be the opposite of Module:init/1 and do any
%% necessary cleaning up. When it returns, the gen_fsm terminates with
%% Reason. The return value is ignored.
%%--------------------------------------------------------------------
terminate(_Reason, connection, _S=#state{negotiated_version = Version,
				      connection_states = ConnectionStates,
				      transport_cb = Transport,
				      socket = Socket}) ->
    {BinAlert, _} = encode_alert(?ALERT_REC(?WARNING,?CLOSE_NOTIFY),
				 Version, ConnectionStates),
    Transport:send(Socket, BinAlert),
    Transport:close(Socket);
terminate(_Reason, _StateName, _S=#state{transport_cb = Transport, socket = Socket}) ->
    Transport:close(Socket),
    ok.

%%--------------------------------------------------------------------
%% Function:
%% code_change(OldVsn, StateName, State, Extra) -> {ok, StateName, NewState}
%% Description: Convert process state when code is changed
%%--------------------------------------------------------------------
code_change(_OldVsn, StateName, State, _Extra) ->
    {ok, StateName, State}.

%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------
start_fsm(Role, Host, Port, Socket, Opts,  User, {CbModule, _,_} = CbInfo, 
	  Timeout) -> 
    case ssl_connection_sup:start_child([Role, Host, Port, Socket, 
                                         Opts, User, CbInfo]) of
        {ok, Pid} -> 
            CbModule:controlling_process(Socket, Pid),
	    send_event(Pid, socket_control),
            case sync_send_all_state_event(Pid, started, Timeout) of
                connected ->
                    {ok, sslsocket(Pid)};
                {error, Reason} ->
                    {error, Reason}
            end;
	{error, Reason} ->
            {error, Reason}
    end.
 
ssl_init(SslOpts, Role) ->
    {ok, CertDbRef, CacheRef, OwnCert} = init_certificates(SslOpts, Role),
    PrivateKey =
	init_private_key(SslOpts#ssl_options.key, SslOpts#ssl_options.keyfile,
			 SslOpts#ssl_options.password, Role),
    ?DBG_TERM(PrivateKey),
    {ok, CertDbRef, CacheRef, OwnCert, PrivateKey}.

init_certificates(#ssl_options{cacertfile = CACertFile,
			       certfile = CertFile}, Role) ->

    case ssl_manager:connection_init(CACertFile, Role) of
	{ok, CertDbRef, CacheRef} ->
	    init_certificates(CertDbRef, CacheRef, CertFile, Role);
	{error, {badmatch, _Error}} ->
	    Report = io_lib:format("SSL: Error ~p Initializing: ~p ~n",
				   [_Error, CACertFile]),
	    error_logger:error_report(Report),
	    throw(ecacertfile);
	{error, _Error} ->
	    Report = io_lib:format("SSL: Error ~p Initializing: ~p ~n",
				   [_Error, CACertFile]),
	    error_logger:error_report(Report),
	    throw(ecacertfile)
    end.

init_certificates(CertDbRef, CacheRef, CertFile, client) -> 
    try 
	[OwnCert] = ssl_certificate:file_to_certificats(CertFile),
	{ok, CertDbRef, CacheRef, OwnCert}
    catch _E:_R  ->
	    {ok, CertDbRef, CacheRef, undefined}
    end;

init_certificates(CertDbRef, CacheRef, CertFile, server) ->
     try 
	[OwnCert] = ssl_certificate:file_to_certificats(CertFile),
	{ok, CertDbRef, CacheRef, OwnCert}
     catch
	 _E:{badmatch, _R={error,_}} ->
	     Report = io_lib:format("SSL: ~p: ~p:~p ~s~n  ~p~n",
				    [?LINE, _E,_R, CertFile, erlang:get_stacktrace()]),
	     error_logger:error_report(Report),
	     throw(ecertfile);
	 _E:_R  ->
	     Report = io_lib:format("SSL: ~p: ~p:~p ~s~n  ~p~n",
				    [?LINE, _E,_R, CertFile, erlang:get_stacktrace()]),
	     error_logger:error_report(Report),
	     throw(ecertfile)
     end.

init_private_key(undefined, "", _Password, client) -> 
    undefined;
init_private_key(undefined, KeyFile, Password, _)  -> 
    try 
	{ok, List} = ssl_manager:cache_pem_file(KeyFile),
	[Der] = [Der || Der = {PKey, _ , _} <- List,
			PKey =:= rsa_private_key orelse PKey =:= dsa_private_key],
	{ok, Decoded} = public_key:decode_private_key(Der,Password),
	Decoded
    catch
	_E:{badmatch, _R={error,_}} ->
	    Report = io_lib:format("SSL: ~p: ~p:~p ~s~n  ~p~n",
				   [?LINE, _E,_R, KeyFile, erlang:get_stacktrace()]),
	    error_logger:error_report(Report),
	    throw(ekeyfile);
	_E:_R ->
	    Report = io_lib:format("SSL: ~p: ~p:~p ~s~n  ~p~n",
				   [?LINE, _E,_R, KeyFile, erlang:get_stacktrace()]),
	    error_logger:error_report(Report),
	    throw(ekeyfile)
    end;
init_private_key(PrivateKey, _, _,_) ->
    PrivateKey.

send_event(FsmPid, Event) ->
    gen_fsm:send_event(FsmPid, Event).

sync_send_event(FsmPid, Event, Timeout) ->
    try gen_fsm:sync_send_event(FsmPid, Event, Timeout) of
 	Reply ->
 	    Reply
    catch
 	exit:{noproc, _} ->
 	    {error, closed};
 	exit:{timeout, _} ->
 	    {error, timeout};
	exit:{normal, _} ->
	    {error, closed}
    end.



send_all_state_event(FsmPid, Event) ->
    gen_fsm:send_all_state_event(FsmPid, Event).

sync_send_all_state_event(FsmPid, Event) ->
    sync_send_all_state_event(FsmPid, Event, ?DEFAULT_TIMEOUT).

sync_send_all_state_event(FsmPid, Event, Timeout) ->
    try gen_fsm:sync_send_all_state_event(FsmPid, Event, Timeout)
    catch
 	exit:{noproc, _} ->
 	    {error, closed};
 	exit:{timeout, _} ->
 	    {error, timeout};
	exit:{normal, _} ->
	    {error, closed}
    end.

%% Events: #alert{}
alert_event(Alert) ->
    send_all_state_event(self(), Alert).

certify_client(#state{client_certificate_requested = true, role = client,
                      connection_states = ConnectionStates0,
                      transport_cb = Transport,
                      negotiated_version = Version,
                      cert_db_ref = CertDbRef,
                      own_cert = OwnCert,
                      socket = Socket,
                      tls_handshake_hashes = Hashes0} = State) ->
    Certificate = ssl_handshake:certificate(OwnCert, CertDbRef, client),
    {BinCert, ConnectionStates1, Hashes1} =
        encode_handshake(Certificate, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinCert),
            State#state{connection_states = ConnectionStates1, 
                        tls_handshake_hashes = Hashes1};
certify_client(#state{client_certificate_requested = false} = State) ->
    State.

verify_client_cert(#state{client_certificate_requested = true, role = client,
			  connection_states = ConnectionStates0,
			  transport_cb = Transport,
			  negotiated_version = Version,
			  own_cert = OwnCert,
			  socket = Socket,
			  key_algorithm = KeyAlg,
			  private_key = PrivateKey,
			  session = #session{master_secret = MasterSecret},
			  tls_handshake_hashes = Hashes0} = State) ->
    case ssl_handshake:client_certificate_verify(OwnCert, MasterSecret, 
						 Version, KeyAlg, 
						 PrivateKey, Hashes0) of
	ignore -> %% No key or cert or fixed_diffie_hellman
            State;
        Verified ->
	    SigAlg = ssl_handshake:sig_alg(KeyAlg),
            {BinVerified, ConnectionStates1, Hashes1} = 
                encode_handshake(Verified, SigAlg, Version, 
                                 ConnectionStates0, Hashes0),
            Transport:send(Socket, BinVerified),
            State#state{connection_states = ConnectionStates1,
                        tls_handshake_hashes = Hashes1}
    end;
verify_client_cert(#state{client_certificate_requested = false} = State) ->
    State.

do_server_hello(Type, #state{negotiated_version = Version,
			     session = Session,
			     connection_states = ConnectionStates0} 
		= State0) when is_atom(Type) -> 
    ServerHello = 
        ssl_handshake:server_hello(Session#session.session_id, Version, 
                                   ConnectionStates0),
    State = server_hello(ServerHello, State0),
    
    case Type of	
	new ->
	    do_server_hello(ServerHello, State);
	resumed ->
	    case ssl_handshake:master_secret(Version, Session,
					     ConnectionStates0, server) of
		{_, ConnectionStates1} ->
		    State1 = State#state{connection_states=ConnectionStates1, 
					 session = Session},
		    {ConnectionStates, Hashes} = finalize_server_handshake(State1),
		    Resumed = State1#state{connection_states = ConnectionStates,
					   tls_handshake_hashes = Hashes},
		    {next_state, abbreviated, next_record(Resumed)};
		#alert{} = Alert ->
		    handle_own_alert(Alert, Version, hello, State), 
		    {stop, normal, State}
	    end
    end;

do_server_hello(#server_hello{cipher_suite = CipherSuite,
			      compression_method = Compression,
			      session_id = SessionId}, 
		#state{session = Session0,
		       negotiated_version = Version} = State0) ->
    try server_certify_and_key_exchange(State0) of 
        #state{} = State1 ->
            State = server_hello_done(State1),
	    Session = 
		Session0#session{session_id = SessionId,
				 cipher_suite = CipherSuite,
				 compression_method = Compression},
            {next_state, certify, State#state{session = Session}}
    catch        
        #alert{} = Alert ->  
	    handle_own_alert(Alert, Version, hello, State0),
	    {stop, normal, State0}
    end.

client_certify_and_key_exchange(#state{negotiated_version = Version} = 
				State0) ->
    try do_client_certify_and_key_exchange(State0) of 
        State1 = #state{} ->
	    {ConnectionStates, Hashes} = finalize_client_handshake(State1),
            State = State1#state{connection_states = ConnectionStates,
				 %% Reinitialize 
				 client_certificate_requested = false,
				 tls_handshake_hashes = Hashes},
            {next_state, cipher, next_record(State)}
    
    catch        
        #alert{} = Alert ->  
	    handle_own_alert(Alert, Version, certify_foo, State0),
            {stop, normal, State0}
    end.

do_client_certify_and_key_exchange(State0) ->
    State1 = certify_client(State0), 
    State2 = key_exchange(State1),
    verify_client_cert(State2).

server_certify_and_key_exchange(State0) ->
    State1 = certify_server(State0), 
    State2 = key_exchange(State1),
    request_client_cert(State2).
    
server_hello(ServerHello, #state{transport_cb = Transport,
                                 socket = Socket,
                                 negotiated_version = Version,
                                 connection_states = ConnectionStates0,
                                 tls_handshake_hashes = Hashes0} = State) ->
    CipherSuite = ServerHello#server_hello.cipher_suite,
    {KeyAlgorithm, _, _, _} = ssl_cipher:suite_definition(CipherSuite),
    %% Version = ServerHello#server_hello.server_version, TODO ska kontrolleras
    {BinMsg, ConnectionStates1, Hashes1} = 
        encode_handshake(ServerHello, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{connection_states = ConnectionStates1,
                tls_handshake_hashes = Hashes1,
                key_algorithm = KeyAlgorithm}.
   
server_hello_done(#state{transport_cb = Transport,
                         socket = Socket,
                         negotiated_version = Version,
                         connection_states = ConnectionStates,
                         tls_handshake_hashes = Hashes} = State0) ->
    
    HelloDone = ssl_handshake:server_hello_done(),

    {BinHelloDone, NewConnectionStates, NewHashes} =
        encode_handshake(HelloDone, Version, ConnectionStates, Hashes),
    Transport:send(Socket, BinHelloDone),
    State = State0#state{connection_states = NewConnectionStates,
                         tls_handshake_hashes = NewHashes},
    next_record(State).
    
certify_server(#state{transport_cb = Transport,
                      socket = Socket,
                      negotiated_version = Version,
                      connection_states = ConnectionStates,
                      tls_handshake_hashes = Hashes,
                      cert_db_ref = CertDbRef,
                      own_cert = OwnCert} = State) ->

    case ssl_handshake:certificate(OwnCert, CertDbRef, server) of
	CertMsg = #certificate{} ->
	    {BinCertMsg, NewConnectionStates, NewHashes} =
		encode_handshake(CertMsg, Version, ConnectionStates, Hashes),
	    Transport:send(Socket, BinCertMsg),
	    State#state{connection_states = NewConnectionStates,
			tls_handshake_hashes = NewHashes
		       };
	Alert = #alert{} ->
	    throw(Alert)
    end.

key_exchange(#state{role = server, key_algorithm = Algo} = State) 
  when Algo == rsa;
       Algo == dh_dss;
       Algo == dh_rsa ->
    State;

key_exchange(#state{role = server, key_algorithm = rsa_export} = State) ->
    %% TODO when the public key in the server certificate is
    %% less than or equal to 512 bits in length dont send key_exchange
    %% but do it otherwise
    State;

key_exchange(#state{role = server, key_algorithm = Algo,
		    diffie_hellman_params = Params,
		    connection_states = ConnectionStates0,
		    negotiated_version = Version,
		    tls_handshake_hashes = Hashes0,
		    socket = Socket,
		    transport_cb = Transport
		   } = State) 
  when Algo == dhe_dss;
       Algo == dhe_dss_export;
       Algo == dhe_rsa;
       Algo == dhe_rsa_export  ->
    Msg =  ssl_handshake:key_exchange(server, Params),
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Msg, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{connection_states = ConnectionStates1,
                tls_handshake_hashes = Hashes1};

key_exchange(#state{role = server, key_algorithm = dh_anon,
			    connection_states = ConnectionStates0,
			    negotiated_version = Version,
			    tls_handshake_hashes = Hashes0,
			    socket = Socket,
			    transport_cb = Transport
		   } = State) ->
    Msg = ssl_handshake:key_exchange(server, anonymous),    
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Msg, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{connection_states = ConnectionStates1,
                tls_handshake_hashes = Hashes1};
   
key_exchange(#state{role = client, 
		    connection_states = ConnectionStates0,
		    key_algorithm = rsa,
		    public_key_info = PublicKeyInfo,
		    negotiated_version = Version,
		    premaster_secret = PremasterSecret,
		    socket = Socket, transport_cb = Transport,
		    tls_handshake_hashes = Hashes0} = State) ->
    Msg = rsa_key_exchange(PremasterSecret, PublicKeyInfo),    
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Msg, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{connection_states = ConnectionStates1,
                tls_handshake_hashes = Hashes1};

key_exchange(#state{role = client, 
		    connection_states = ConnectionStates0,
		    key_algorithm = Algorithm,
		    public_key_info = PublicKeyInfo,
		    negotiated_version = Version,
		    diffie_hellman_params = Params,
		    own_cert = Cert,
		    socket = Socket, transport_cb = Transport,
		    tls_handshake_hashes = Hashes0} = State) 
  when Algorithm == dhe_dss;
       Algorithm == dhe_dss_export;
       Algorithm == dhe_rsa;
       Algorithm == dhe_rsa_export ->
    Msg = dh_key_exchange(Cert, Params, PublicKeyInfo),    
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Msg, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{connection_states = ConnectionStates1,
                tls_handshake_hashes = Hashes1}.

rsa_key_exchange(PremasterSecret, PublicKeyInfo = {Algorithm, _, _})  
  when Algorithm == ?rsaEncryption;
       Algorithm == ?md2WithRSAEncryption;
       Algorithm == ?md5WithRSAEncryption;
       Algorithm == ?sha1WithRSAEncryption ->
    ssl_handshake:key_exchange(client, 
			       {premaster_secret, PremasterSecret,
				PublicKeyInfo});

rsa_key_exchange(_, _) ->
    throw (?ALERT_REC(?FATAL,?HANDSHAKE_FAILURE)).

dh_key_exchange(OwnCert, Params, PublicKeyInfo) ->
    case public_key:pkix_is_fixed_dh_cert(OwnCert) of
	true ->
	    ssl_handshake:key_exchange(client, fixed_diffie_hellman);
	false ->
	    ssl_handshake:key_exchange(client, {dh, Params, PublicKeyInfo})
    end.

request_client_cert(#state{ssl_options = #ssl_options{verify = verify_peer},
			   connection_states = ConnectionStates0,
			   cert_db_ref = CertDbRef,
			   tls_handshake_hashes = Hashes0,
			   negotiated_version = Version,
			   socket = Socket,
			   transport_cb = Transport} = State) ->
    Msg = ssl_handshake:certificate_request(ConnectionStates0, CertDbRef),
    {BinMsg, ConnectionStates1, Hashes1} =
        encode_handshake(Msg, Version, ConnectionStates0, Hashes0),
    Transport:send(Socket, BinMsg),
    State#state{client_certificate_requested = true,
		connection_states = ConnectionStates1,      
		tls_handshake_hashes = Hashes1};
request_client_cert(#state{ssl_options = #ssl_options{verify = verify_none}} =
		    State) ->
    State.

finalize_client_handshake(#state{connection_states = ConnectionStates0} 
                          = State) ->
    ConnectionStates1 = 
        cipher_protocol(State#state{connection_states = 
                                    ConnectionStates0}),    
    ConnectionStates2 =
        ssl_record:activate_pending_connection_state(ConnectionStates1,
                                                     write),
    finished(State#state{connection_states = ConnectionStates2}).
    

finalize_server_handshake(State) ->
    ConnectionStates0 = cipher_protocol(State),
    ConnectionStates = 
        ssl_record:activate_pending_connection_state(ConnectionStates0, write),
    finished(State#state{connection_states = ConnectionStates}).

cipher_protocol(#state{connection_states = ConnectionStates,
                       socket = Socket,
                       negotiated_version = Version,
                       transport_cb = Transport}) ->
    {BinChangeCipher, NewConnectionStates} =
        encode_change_cipher(#change_cipher_spec{}, Version, ConnectionStates),
    Transport:send(Socket, BinChangeCipher),
    NewConnectionStates.
   
finished(#state{role = Role, socket = Socket, negotiated_version = Version,
                transport_cb = Transport,
		session = Session,
                connection_states = ConnectionStates,
                tls_handshake_hashes = Hashes}) ->
    MasterSecret = Session#session.master_secret,
    Finished = ssl_handshake:finished(Version, Role, MasterSecret, Hashes),
    {BinFinished, NewConnectionStates, NewHashes} = 
        encode_handshake(Finished, Version, ConnectionStates, Hashes),
    Transport:send(Socket, BinFinished),
    {NewConnectionStates, NewHashes}.

handle_server_key(_KeyExchangeMsg, State) ->
    State.
handle_clinet_key(_KeyExchangeMsg, State) ->
    State.

encode_alert(#alert{} = Alert, Version, ConnectionStates) ->
    ?DBG_TERM(Alert),
    ssl_record:encode_alert_record(Alert, Version, ConnectionStates).

encode_change_cipher(#change_cipher_spec{}, Version, ConnectionStates) ->
    ?DBG_TERM(#change_cipher_spec{}),
    ssl_record:encode_change_cipher_spec(Version, ConnectionStates).

encode_handshake(HandshakeRec, Version, ConnectionStates, Hashes) ->
    encode_handshake(HandshakeRec, undefined, Version, 
		     ConnectionStates, Hashes).

encode_handshake(HandshakeRec, SigAlg, Version, ConnectionStates0, Hashes0) ->
    ?DBG_TERM(HandshakeRec),
    Frag = ssl_handshake:encode_handshake(HandshakeRec, Version, SigAlg),
    Hashes1 = ssl_handshake:update_hashes(Hashes0, Frag),
    {E, ConnectionStates1} =
        ssl_record:encode_handshake(Frag, Version, ConnectionStates0),
    {E, ConnectionStates1, Hashes1}.

encode_packet(Data, #socket_options{packet=Packet}) ->
    case Packet of
	0 -> Data;
	1 -> encode_size_packet(Data, 8,  (1 bsl 8) - 1);
	2 -> encode_size_packet(Data, 16, (1 bsl 16) - 1);
	4 -> encode_size_packet(Data, 32, (1 bsl 32) - 1);
	_ ->
	    throw({error, {badarg, {eoptions, {packet, Packet}}}})
    end.

encode_size_packet(Bin, Size, Max) ->
    Len = byte_size(Bin),
    case Len > Max of
	true  -> throw({error, {badarg, {packet_to_large, Len, Max}}});
	false -> <<Len:Size, Bin/binary>>
    end.

encode_data(Data, Version, ConnectionStates) ->
    ssl_record:encode_data(Data, Version, ConnectionStates).

decode_alerts(Bin) ->
    decode_alerts(Bin, []).

decode_alerts(<<?BYTE(Level), ?BYTE(Description), Rest/binary>>, Acc) ->
    A = ?ALERT_REC(Level, Description),
    decode_alerts(Rest, [A | Acc]);
decode_alerts(<<>>, Acc) ->
    lists:reverse(Acc, []).

application_data(Data, #state{user_application = {_Mon, Pid},
                              socket_options = SOpts,
                              bytes_to_read = BytesToRead,
                              from = From,
                              user_data_buffer = Buffer0} = State0) ->
    Buffer1 = if 
		  Buffer0 =:= <<>> -> Data;
		  Data =:= <<>> -> Buffer0;
		  true -> <<Buffer0/binary, Data/binary>>
	      end,
    case get_data(SOpts, BytesToRead, Buffer1) of
	{ok, <<>>, Buffer} -> % no reply, we need more data
	    next_record(State0#state{user_data_buffer = Buffer});
	{ok, ClientData, Buffer} -> % Send data
	    SocketOpt = deliver_app_data(SOpts, ClientData, Pid, From),
	    State = State0#state{user_data_buffer = Buffer,
				 from = undefined,
				 bytes_to_read = 0,
				 socket_options = SocketOpt 
				},
	    if
		SocketOpt#socket_options.active =:= false -> 
		    State; %% Passive mode, wait for active once or recv
		Buffer =:= <<>> -> %% Active and empty, get more data
		    next_record(State);
		true -> %% We have more data
		    application_data(<<>>, State)
	    end;
	{error,_Reason} -> %% Invalid packet in packet mode
	    deliver_packet_error(SOpts, Buffer1, Pid, From),
	    {stop, normal, State0}
    end.

%% Picks ClientData 
get_data(#socket_options{active=Active, packet=Raw}, BytesToRead, Buffer) 
  when Raw =:= raw; Raw =:= 0 ->   %% Raw Mode
    if 
	Active =/= false orelse BytesToRead =:= 0  ->
	    %% Active true or once, or passive mode recv(0)  
	    {ok, Buffer, <<>>};
	byte_size(Buffer) >= BytesToRead ->  
	    %% Passive Mode, recv(Bytes) 
	    <<Data:BytesToRead/binary, Rest/binary>> = Buffer,
	    {ok, Data, Rest};
	true ->
	    %% Passive Mode not enough data
	    {ok, <<>>, Buffer}
    end;
get_data(#socket_options{packet=Type, packet_size=Size}, _, Buffer) ->
    PacketOpts = [{packet_size, Size}], 
    case erlang:decode_packet(Type, Buffer, PacketOpts) of
	{more, _} ->
	    {ok, <<>>, Buffer};
	Decoded ->
	    Decoded
    end.

deliver_app_data(SO = #socket_options{active=once}, Data, Pid, From) ->
    send_or_reply(once, Pid, From, format_reply(SO, Data)),
    SO#socket_options{active=false};
deliver_app_data(SO= #socket_options{active=Active}, Data, Pid, From) ->
    send_or_reply(Active, Pid, From, format_reply(SO, Data)),
    SO.

format_reply(#socket_options{active=false, mode=Mode, header=Header}, Data) ->
    {ok, format_reply(Mode, Header, Data)};
format_reply(#socket_options{active=_, mode=Mode, header=Header}, Data) ->
    {ssl, sslsocket(), format_reply(Mode, Header, Data)}.

deliver_packet_error(SO= #socket_options{active=Active}, Data, Pid, From) ->
    send_or_reply(Active, Pid, From, format_packet_error(SO, Data)).

format_packet_error(#socket_options{active=false, mode=Mode}, Data) ->
    {error, {invalid_packet, format_reply(Mode, raw, Data)}};
format_packet_error(#socket_options{active=_, mode=Mode}, Data) ->
    {ssl_error, sslsocket(), {invalid_packet, format_reply(Mode, raw, Data)}}.

format_reply(list,     _, Data) ->  binary_to_list(Data);
format_reply(binary,   0, Data) ->  Data;
format_reply(binary, raw, Data) ->  Data;
format_reply(binary,   N, Data) ->  % Header mode
    <<Header:N/binary, Rest/binary>> = Data,
    [binary_to_list(Header), Rest].

%% tcp_closed
send_or_reply(false, _Pid, undefined, _Data) ->
    Report = io_lib:format("SSL(debug): Unexpected Data ~p ~n",[_Data]),
    error_logger:error_report(Report),
    erlang:error({badarg, _Pid, undefined, _Data}),
    ok;
send_or_reply(false, _Pid, From, Data) ->
    gen_fsm:reply(From, Data);
send_or_reply(_, Pid, _From, Data) ->
    send_user(Pid, Data).

opposite_role(client) ->
    server;
opposite_role(server) ->
    client.

send_user(Pid, Msg) ->
    Pid ! Msg.

%% %% This is the code for {packet,ssl} removed because it was slower 
%% %% than handling it in erlang.
%% next_record(#state{socket = Socket, 
%% 		   tls_buffer = [Msg|Rest],
%% 		   connection_states = ConnectionStates0} = State) ->
%%     Buffer =
%% 	case Rest of
%% 	    [] -> 
%% 		inet:setopts(Socket, [{active,once}]),
%% 		buffer;
%% 	    _ -> Rest
%% 	end,
%%     case Msg of
%% 	#ssl_tls{} ->
%% 	    {Plain, ConnectionStates} =
%% 		ssl_record:decode_cipher_text(Msg, ConnectionStates0),
%% 	    gen_fsm:send_all_state_event(self(), Plain),
%% 	    State#state{tls_buffer=Buffer, connection_states = ConnectionStates};
%% 	{ssl_close, Msg} ->
%% 	    self() ! Msg,
%% 	    State#state{tls_buffer=Buffer}
%%     end;
%% next_record(#state{socket = Socket, tls_buffer = undefined} = State) ->
%%     inet:setopts(Socket, [{active,once}]),
%%     State#state{tls_buffer=continue};
%% next_record(State) ->
%%     State#state{tls_buffer=continue}.

next_record(#state{tls_cipher_texts = [], socket = Socket} = State) ->
    inet:setopts(Socket, [{active,once}]),
    State;
next_record(#state{tls_cipher_texts = [CT | Rest], 
		   connection_states = ConnStates0} = State) ->
    {Plain, ConnStates} = ssl_record:decode_cipher_text(CT, ConnStates0),
    gen_fsm:send_all_state_event(self(), Plain),
    State#state{tls_cipher_texts = Rest, connection_states = ConnStates}.

next_record_if_active(State = 
		      #state{socket_options = 
			     #socket_options{active = false}}) ->    
    State;
next_record_if_active(State) ->
    next_record(State).

register_session(_, _, _, #session{is_resumable = true} = Session) ->
    Session; %% Already registered
register_session(client, Host, Port, Session0) ->
    Session = Session0#session{is_resumable = true},
    ssl_manager:register_session(Host, Port, Session),
    Session;
register_session(server, _, Port, Session0) ->
    Session = Session0#session{is_resumable = true},
    ssl_manager:register_session(Port, Session),
    Session.

invalidate_session(client, Host, Port, Session) ->
    ssl_manager:invalidate_session(Host, Port, Session);
invalidate_session(server, _, Port, Session) ->
    ssl_manager:invalidate_session(Port, Session).

initial_state(Role, Host, Port, Socket, {SSLOptions, SocketOptions}, User,
	      {CbModule, DataTag, CloseTag}) ->
    ConnectionStates = ssl_record:init_connection_states(Role),
    
    SessionCacheCb = case application:get_env(ssl, session_cb) of
			 {ok, Cb} when is_atom(Cb) ->
			    Cb;
			 _  ->
			     ssl_session_cache
		     end,
    
    Monitor = erlang:monitor(process, User),

    #state{socket_options = SocketOptions,
	   %% We do not want to save the password in the state so that
	   %% could be written in the clear into error logs.
	   ssl_options = SSLOptions#ssl_options{password = undefined},	   
	   session = #session{is_resumable = false},
	   transport_cb = CbModule,
	   data_tag = DataTag,
	   close_tag = CloseTag,
	   role = Role,
	   host = Host,
	   port = Port,
	   socket = Socket,
	   connection_states = ConnectionStates,
	   tls_handshake_buffer = <<>>,
	   tls_record_buffer = <<>>,
	   tls_cipher_texts = [],
	   user_application = {Monitor, User},
	   bytes_to_read = 0,
	   user_data_buffer = <<>>,
	   log_alert = true,
	   session_cache_cb = SessionCacheCb
	  }.

sslsocket(Pid) ->
    #sslsocket{pid = Pid, fd = new_ssl}.

sslsocket() ->
    sslsocket(self()).

get_socket_opts(_,[], _, Acc) ->
    {ok, Acc};
get_socket_opts(Socket, [mode | Tags], SockOpts, Acc) ->
    get_socket_opts(Socket, Tags, SockOpts, 
		    [{mode, SockOpts#socket_options.mode} | Acc]);
get_socket_opts(Socket, [packet | Tags], SockOpts, Acc) ->
    get_socket_opts(Socket, Tags, SockOpts, 
		    [{packet, SockOpts#socket_options.packet} | Acc]);
get_socket_opts(Socket, [header | Tags], SockOpts, Acc) ->
    get_socket_opts(Socket, Tags, SockOpts, 
		    [{header, SockOpts#socket_options.header} | Acc]);
get_socket_opts(Socket, [active | Tags], SockOpts, Acc) ->
    get_socket_opts(Socket, Tags, SockOpts, 
		    [{active, SockOpts#socket_options.active} | Acc]);
get_socket_opts(Socket, [Tag | Tags], SockOpts, Acc) ->
    case inet:getopts(Socket, [Tag]) of
	{ok, [Opt]} ->
	    get_socket_opts(Socket, Tags, SockOpts, [Opt | Acc]);
	{error, Error} ->
	    {error, Error}
    end.

set_socket_opts(_, [], SockOpts, []) ->
    SockOpts;
set_socket_opts(Socket, [], SockOpts, Other) ->
    %% Set non emulated options 
    inet:setopts(Socket, Other),
    SockOpts;
set_socket_opts(Socket, [{mode, Mode}| Opts], SockOpts, Other) ->
    set_socket_opts(Socket, Opts, SockOpts#socket_options{mode = Mode}, Other);
set_socket_opts(Socket, [{packet, Packet}| Opts], SockOpts, Other) ->
    set_socket_opts(Socket, Opts, 
		    SockOpts#socket_options{packet = Packet}, Other);
set_socket_opts(Socket, [{header, Header}| Opts], SockOpts, Other) ->
    set_socket_opts(Socket, Opts, 
		    SockOpts#socket_options{header = Header}, Other);
set_socket_opts(Socket, [{active, Active}| Opts], SockOpts, Other) ->
    set_socket_opts(Socket, Opts, 
		    SockOpts#socket_options{active = Active}, Other);
set_socket_opts(Socket, [Opt | Opts], SockOpts, Other) ->
    set_socket_opts(Socket, Opts, SockOpts, [Opt | Other]).

alert_user(From, Alert, Role) ->
    alert_user(false, no_pid, From, Alert, Role).

alert_user(false = Active, Pid, From,  Alert, Role) ->
    ReasonCode = ssl_alert:reason_code(Alert, Role),
    send_or_reply(Active, Pid, From, {error, ReasonCode});
alert_user(Active, Pid, From, Alert, Role) ->
    case ssl_alert:reason_code(Alert, Role) of
	closed ->
	    send_or_reply(Active, Pid, From,
			  {ssl_closed, sslsocket()});
	ReasonCode ->
	    send_or_reply(Active, Pid, From,
			  {ssl_error, sslsocket(), ReasonCode})
    end.

log_alert(true, StateName, Alert) ->
    Txt = ssl_alert:alert_txt(Alert),
    error_logger:format("SSL: ~p: ~s\n", [StateName, Txt]);
log_alert(false, _, _) ->
    ok.

handle_own_alert(Alert, Version, StateName, 
		 #state{transport_cb = Transport,
			socket = Socket,
			from = User,
			role = Role,
			connection_states = ConnectionStates,
			log_alert = Log}) ->
    {BinMsg, _} =
	encode_alert(Alert, Version, ConnectionStates),
    Transport:send(Socket, BinMsg),
    log_alert(Log, StateName, Alert),
    alert_user(User, Alert, Role).

make_premaster_secret({MajVer, MinVer}) ->
    Rand = crypto:rand_bytes(?NUM_OF_PREMASTERSECRET_BYTES-2),
    <<?BYTE(MajVer), ?BYTE(MinVer), Rand/binary>>.