1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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
|
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
/* Transport Security Layer (TLS)
* Copyright (c) 2003-2004 Carlos Guzman Alvarez
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
using System;
using System.Text;
using System.Collections;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;
using Mono.Security.Cryptography;
using Mono.Security.Protocol.Tls.Handshake;
namespace Mono.Security.Protocol.Tls
{
internal abstract class Context
{
#region Internal Constants
internal const short MAX_FRAGMENT_SIZE = 16384; // 2^14
internal const short TLS1_PROTOCOL_CODE = (0x03 << 8) | 0x01;
internal const short SSL3_PROTOCOL_CODE = (0x03 << 8) | 0x00;
internal const long UNIX_BASE_TICKS = 621355968000000000;
#endregion
#region Fields
// Protocol version
private SecurityProtocolType securityProtocol;
// Sesison ID
private byte[] sessionId;
// Compression method
private SecurityCompressionType compressionMethod;
// Information sent and request by the server in the Handshake protocol
private TlsServerSettings serverSettings;
// Client configuration
private TlsClientSettings clientSettings;
// Cipher suite information
private CipherSuite cipher;
private CipherSuiteCollection supportedCiphers;
// Last handshake message received
private HandshakeType lastHandshakeMsg;
// Handshake negotiation state
private HandshakeState handshakeState;
// Misc
private bool isActual;
private bool connectionEnd;
private bool protocolNegotiated;
// Sequence numbers
private long writeSequenceNumber;
private long readSequenceNumber;
// Random data
private byte[] clientRandom;
private byte[] serverRandom;
private byte[] randomCS;
private byte[] randomSC;
// Key information
private byte[] masterSecret;
private byte[] clientWriteMAC;
private byte[] serverWriteMAC;
private byte[] clientWriteKey;
private byte[] serverWriteKey;
private byte[] clientWriteIV;
private byte[] serverWriteIV;
// Handshake hashes
private TlsStream handshakeMessages;
// Secure Random generator
private RandomNumberGenerator random;
// Record protocol
private RecordProtocol recordProtocol;
#endregion
#region Properties
public bool ProtocolNegotiated
{
get { return this.protocolNegotiated; }
set { this.protocolNegotiated = value; }
}
public SecurityProtocolType SecurityProtocol
{
get
{
if ((this.securityProtocol & SecurityProtocolType.Tls) == SecurityProtocolType.Tls ||
(this.securityProtocol & SecurityProtocolType.Default) == SecurityProtocolType.Default)
{
return SecurityProtocolType.Tls;
}
else
{
if ((this.securityProtocol & SecurityProtocolType.Ssl3) == SecurityProtocolType.Ssl3)
{
return SecurityProtocolType.Ssl3;
}
}
throw new NotSupportedException("Unsupported security protocol type");
}
set { this.securityProtocol = value; }
}
public SecurityProtocolType SecurityProtocolFlags
{
get { return this.securityProtocol; }
}
public short Protocol
{
get
{
switch (this.SecurityProtocol)
{
case SecurityProtocolType.Tls:
case SecurityProtocolType.Default:
return Context.TLS1_PROTOCOL_CODE;
case SecurityProtocolType.Ssl3:
return Context.SSL3_PROTOCOL_CODE;
case SecurityProtocolType.Ssl2:
default:
throw new NotSupportedException("Unsupported security protocol type");
}
}
}
public byte[] SessionId
{
get { return this.sessionId; }
set { this.sessionId = value; }
}
public SecurityCompressionType CompressionMethod
{
get { return this.compressionMethod; }
set { this.compressionMethod = value; }
}
public TlsServerSettings ServerSettings
{
get { return this.serverSettings; }
}
public TlsClientSettings ClientSettings
{
get { return this.clientSettings; }
}
public bool IsActual
{
get { return this.isActual; }
set { this.isActual = value; }
}
public HandshakeType LastHandshakeMsg
{
get { return this.lastHandshakeMsg; }
set { this.lastHandshakeMsg = value; }
}
public HandshakeState HandshakeState
{
get { return this.handshakeState; }
set { this.handshakeState = value; }
}
public bool ConnectionEnd
{
get { return this.connectionEnd; }
set { this.connectionEnd = value; }
}
public CipherSuite Cipher
{
get { return this.cipher; }
set
{
this.cipher = value;
this.cipher.Context = this;
}
}
public CipherSuiteCollection SupportedCiphers
{
get { return supportedCiphers; }
set { supportedCiphers = value; }
}
public TlsStream HandshakeMessages
{
get { return this.handshakeMessages; }
}
public long WriteSequenceNumber
{
get { return this.writeSequenceNumber; }
set { this.writeSequenceNumber = value; }
}
public long ReadSequenceNumber
{
get { return this.readSequenceNumber; }
set { this.readSequenceNumber = value; }
}
public byte[] ClientRandom
{
get { return this.clientRandom; }
set { this.clientRandom = value; }
}
public byte[] ServerRandom
{
get { return this.serverRandom; }
set { this.serverRandom = value; }
}
public byte[] RandomCS
{
get { return this.randomCS; }
set { this.randomCS = value; }
}
public byte[] RandomSC
{
get { return this.randomSC; }
set { this.randomSC = value; }
}
public byte[] MasterSecret
{
get { return this.masterSecret; }
set { this.masterSecret = value; }
}
public byte[] ClientWriteMAC
{
get { return this.clientWriteMAC; }
set { this.clientWriteMAC = value; }
}
public byte[] ServerWriteMAC
{
get { return this.serverWriteMAC; }
set { this.serverWriteMAC = value; }
}
public byte[] ClientWriteKey
{
get { return this.clientWriteKey; }
set { this.clientWriteKey = value; }
}
public byte[] ServerWriteKey
{
get { return this.serverWriteKey; }
set { this.serverWriteKey = value; }
}
public byte[] ClientWriteIV
{
get { return this.clientWriteIV; }
set { this.clientWriteIV = value; }
}
public byte[] ServerWriteIV
{
get { return this.serverWriteIV; }
set { this.serverWriteIV = value; }
}
public RecordProtocol RecordProtocol
{
get { return this.recordProtocol; }
set { this.recordProtocol = value; }
}
#endregion
#region Constructors
public Context(SecurityProtocolType securityProtocolType)
{
this.SecurityProtocol = securityProtocolType;
this.compressionMethod = SecurityCompressionType.None;
this.serverSettings = new TlsServerSettings();
this.clientSettings = new TlsClientSettings();
this.handshakeMessages = new TlsStream();
this.sessionId = null;
this.handshakeState = HandshakeState.None;
this.random = RandomNumberGenerator.Create();
}
#endregion
#region Methods
public int GetUnixTime()
{
DateTime now = DateTime.UtcNow;
return (int)(now.Ticks - UNIX_BASE_TICKS / TimeSpan.TicksPerSecond);
}
public byte[] GetSecureRandomBytes(int count)
{
byte[] secureBytes = new byte[count];
this.random.GetNonZeroBytes(secureBytes);
return secureBytes;
}
public virtual void Clear()
{
this.compressionMethod = SecurityCompressionType.None;
this.serverSettings = new TlsServerSettings();
this.clientSettings = new TlsClientSettings();
this.handshakeMessages = new TlsStream();
this.sessionId = null;
this.handshakeState = HandshakeState.None;
this.ClearKeyInfo();
}
public virtual void ClearKeyInfo()
{
// Clear Master Secret
this.masterSecret = null;
// Clear client and server random
this.clientRandom = null;
this.serverRandom = null;
this.randomCS = null;
this.randomSC = null;
// Clear client keys
this.clientWriteKey = null;
this.clientWriteIV = null;
// Clear server keys
this.serverWriteKey = null;
this.serverWriteIV = null;
// Reset handshake messages
this.handshakeMessages.Reset();
// Clear MAC keys if protocol is different than Ssl3
if (this.securityProtocol != SecurityProtocolType.Ssl3)
{
this.clientWriteMAC = null;
this.serverWriteMAC = null;
}
}
public SecurityProtocolType DecodeProtocolCode(short code)
{
switch (code)
{
case Context.TLS1_PROTOCOL_CODE:
return SecurityProtocolType.Tls;
case Context.SSL3_PROTOCOL_CODE:
return SecurityProtocolType.Ssl3;
default:
throw new NotSupportedException("Unsupported security protocol type");
}
}
#endregion
}
}
|