mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Client/TlsClientKeyExchange.cs

   1 /* Transport Security Layer (TLS)
   2  * Copyright (c) 2003-2004 Carlos Guzman Alvarez
   3  *
   4  * Permission is hereby granted, free of charge, to any person
   5  * obtaining a copy of this software and associated documentation
   6  * files (the "Software"), to deal in the Software without restriction,
   7  * including without limitation the rights to use, copy, modify, merge,
   8  * publish, distribute, sublicense, and/or sell copies of the Software,
   9  * and to permit persons to whom the Software is furnished to do so,
  10  * subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included
  13  * in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  17  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 using System;
  26 using System.IO;
  27 using System.Security.Cryptography;
  28
  29 namespace Mono.Security.Protocol.Tls.Handshake.Client
  30 {
  31         internal class TlsClientKeyExchange : TlsHandshakeMessage
  32         {
  33                 #region Constructors
  34
  35                 public TlsClientKeyExchange (Context context) :
  36                         base(context,
  37                                 TlsHandshakeType.ClientKeyExchange)
  38                 {
  39                 }
  40
  41                 #endregion
  42
  43                 #region Protected Methods
  44
  45                 protected override void ProcessAsSsl3()
  46                 {
  47                         // Compute pre master secret
  48                         byte[] preMasterSecret = this.Context.Cipher.CreatePremasterSecret();
  49
  50                         // Create a new RSA key
  51                         RSA rsa = this.Context.Cipher.CertificateRSA();
  52
  53                         // Encrypt premaster_sercret
  54                         RSAPKCS1KeyExchangeFormatter formatter = new RSAPKCS1KeyExchangeFormatter(rsa);
  55
  56                         // Write the preMasterSecret encrypted
  57                         byte[] buffer = formatter.CreateKeyExchange(preMasterSecret);
  58                         this.Write(buffer);
  59
  60                         // Create master secret
  61                         this.Context.Cipher.ComputeMasterSecret(preMasterSecret);
  62
  63                         // Create keys
  64                         this.Context.Cipher.ComputeKeys();
  65
  66                         // Clear resources
  67                         rsa.Clear();
  68                 }
  69
  70                 protected override void ProcessAsTls1()
  71                 {
  72                         // Compute pre master secret
  73                         byte[] preMasterSecret = this.Context.Cipher.CreatePremasterSecret();
  74
  75                         // Create a new RSA key
  76                         RSA rsa = this.Context.Cipher.CertificateRSA();
  77
  78                         // Encrypt premaster_sercret
  79                         RSAPKCS1KeyExchangeFormatter formatter = new RSAPKCS1KeyExchangeFormatter(rsa);
  80
  81                         // Write the preMasterSecret encrypted
  82                         byte[] buffer = formatter.CreateKeyExchange(preMasterSecret);
  83                         this.Write((short)buffer.Length);
  84                         this.Write(buffer);
  85
  86                         // Create master secret
  87                         this.Context.Cipher.ComputeMasterSecret(preMasterSecret);
  88
  89                         // Create keys
  90                         this.Context.Cipher.ComputeKeys();
  91
  92                         // Clear resources
  93                         rsa.Clear();
  94                 }
  95
  96                 #endregion
  97         }
  98 }