mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Server/TlsClientFinished.cs

   1 // Transport Security Layer (TLS)
   2 // Copyright (c) 2003-2004 Carlos Guzman Alvarez
   3
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining
   6 // a copy of this software and associated documentation files (the
   7 // "Software"), to deal in the Software without restriction, including
   8 // without limitation the rights to use, copy, modify, merge, publish,
   9 // distribute, sublicense, and/or sell copies of the Software, and to
  10 // permit persons to whom the Software is furnished to do so, subject to
  11 // the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be
  14 // included in all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23 //
  24
  25 using System;
  26 using System.Security.Cryptography;
  27
  28 using Mono.Security.Cryptography;
  29
  30 namespace Mono.Security.Protocol.Tls.Handshake.Server
  31 {
  32         internal class TlsClientFinished : HandshakeMessage
  33         {
  34                 #region Constructors
  35
  36                 public TlsClientFinished(Context context, byte[] buffer)
  37                         : base(context, HandshakeType.Finished,  buffer)
  38                 {
  39                 }
  40
  41                 #endregion
  42
  43                 #region Protected Methods
  44
  45                 protected override void ProcessAsSsl3()
  46                 {
  47                         bool decryptError = false;
  48
  49                         // Compute handshake messages hashes
  50                         HashAlgorithm hash = new SslHandshakeHash(this.Context.MasterSecret);
  51
  52                         TlsStream data = new TlsStream();
  53                         data.Write(this.Context.HandshakeMessages.ToArray());
  54                         data.Write((int)0x434C4E54);
  55
  56                         hash.TransformFinalBlock(data.ToArray(), 0, (int)data.Length);
  57
  58                         data.Reset();
  59
  60                         byte[] clientHash       = this.ReadBytes((int)Length);
  61                         byte[] serverHash       = hash.Hash;
  62
  63                         // Check client prf against server prf
  64                         if (clientHash.Length != serverHash.Length)
  65                         {
  66                                 decryptError = true;
  67                         }
  68                         else
  69                         {
  70                                 for (int i = 0; i < clientHash.Length; i++)
  71                                 {
  72                                         if (clientHash[i] != serverHash[i])
  73                                         {
  74                                                 decryptError = true;
  75                                                 break;
  76                                         }
  77                                 }
  78                         }
  79
  80                         if (decryptError)
  81                         {
  82                                 throw new TlsException(AlertDescription.DecryptError, "Decrypt error.");
  83                         }
  84                 }
  85
  86                 protected override void ProcessAsTls1()
  87                 {
  88                         byte[]                  clientPRF               = this.ReadBytes((int)this.Length);
  89                         HashAlgorithm   hash                    = new MD5SHA1();
  90                         bool                    decryptError    = false;
  91
  92                         hash.ComputeHash(
  93                                 this.Context.HandshakeMessages.ToArray(),
  94                                 0,
  95                                 (int)this.Context.HandshakeMessages.Length);
  96
  97                         byte[] serverPRF = this.Context.Cipher.PRF(
  98                                 this.Context.MasterSecret, "client finished", hash.Hash, 12);
  99
 100                         // Check client prf against server prf
 101                         if (clientPRF.Length != serverPRF.Length)
 102                         {
 103                                 decryptError = true;
 104                         }
 105                         else
 106                         {
 107                                 for (int i = 0; i < serverPRF.Length; i++)
 108                                 {
 109                                         if (clientPRF[i] != serverPRF[i])
 110                                         {
 111                                                 decryptError = true;
 112                                         }
 113                                 }
 114                         }
 115
 116                         if (decryptError)
 117                         {
 118                                 throw new TlsException(AlertDescription.DecryptError, "Decrypt error.");
 119                         }
 120                 }
 121
 122                 #endregion
 123         }
 124 }