mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslHandshakeHash.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 namespace Mono.Security.Protocol.Tls
  29 {
  30         internal class SslHandshakeHash : System.Security.Cryptography.HashAlgorithm
  31         {
  32                 #region Fields
  33
  34                 private HashAlgorithm   md5;
  35                 private HashAlgorithm   sha;
  36                 private bool                    hashing;
  37                 private byte[]                  secret;
  38                 private byte[]                  innerPadMD5;
  39                 private byte[]                  outerPadMD5;
  40                 private byte[]                  innerPadSHA;
  41                 private byte[]                  outerPadSHA;
  42
  43                 #endregion
  44
  45                 #region Constructors
  46
  47                 public SslHandshakeHash(byte[] secret)
  48                 {
  49                         // Create md5 and sha1 hashes
  50                         this.md5 = HashAlgorithm.Create("MD5");
  51                         this.sha = HashAlgorithm.Create("SHA1");
  52
  53                         // Set HashSizeValue
  54                         this.HashSizeValue = md5.HashSize + sha.HashSize;
  55
  56                         // Update secret
  57                         this.secret = secret;
  58
  59                         this.Initialize();
  60                 }
  61
  62                 #endregion
  63
  64                 #region Methods
  65
  66                 public override void Initialize()
  67                 {
  68                         this.md5.Initialize();
  69                         this.sha.Initialize();
  70                         this.initializePad();
  71                         this.hashing = false;
  72                 }
  73
  74                 protected override byte[] HashFinal()
  75                 {
  76                         if (!this.hashing)
  77                         {
  78                                 this.hashing = true;
  79                         }
  80
  81                         // Finalize the md5 hash
  82                         this.md5.TransformBlock(this.secret, 0, this.secret.Length, this.secret, 0);
  83                         this.md5.TransformFinalBlock(this.innerPadMD5, 0, this.innerPadMD5.Length);
  84
  85                         byte[] firstResultMD5 = this.md5.Hash;
  86
  87                         this.md5.Initialize();
  88                         this.md5.TransformBlock(this.secret, 0, this.secret.Length, this.secret, 0);
  89                         this.md5.TransformBlock(this.outerPadMD5, 0, this.outerPadMD5.Length, this.outerPadMD5, 0);
  90                         this.md5.TransformFinalBlock(firstResultMD5, 0, firstResultMD5.Length);
  91
  92                         // Finalize the sha1 hash
  93                         this.sha.TransformBlock(this.secret, 0, this.secret.Length, this.secret, 0);
  94                         this.sha.TransformFinalBlock(this.innerPadSHA, 0, this.innerPadSHA.Length);
  95
  96                         byte[] firstResultSHA = this.sha.Hash;
  97
  98                         this.sha.Initialize();
  99                         this.sha.TransformBlock(this.secret, 0, this.secret.Length, this.secret, 0);
 100                         this.sha.TransformBlock(this.outerPadSHA, 0, this.outerPadSHA.Length, this.outerPadSHA, 0);
 101                         this.sha.TransformFinalBlock(firstResultSHA, 0, firstResultSHA.Length);
 102
 103                         this.Initialize();
 104
 105                         byte[] result = new byte[36];
 106
 107                         Buffer.BlockCopy(this.md5.Hash, 0, result, 0, 16);
 108                         Buffer.BlockCopy(this.sha.Hash, 0, result, 16, 20);
 109
 110                         return result;
 111                 }
 112
 113                 protected override void HashCore(byte[] array, int ibStart, int cbSize)
 114                 {
 115                         if (!this.hashing)
 116                         {
 117                                 this.hashing = true;
 118                         }
 119
 120                         this.md5.TransformBlock(array, ibStart, cbSize, array, ibStart);
 121                         this.sha.TransformBlock(array, ibStart, cbSize, array, ibStart);
 122                 }
 123
 124                 public byte[] CreateSignature(RSA rsa)
 125                 {
 126                         if (rsa == null)
 127                         {
 128                                 throw new CryptographicUnexpectedOperationException ("missing key");
 129                         }
 130
 131                         RSASslSignatureFormatter f = new RSASslSignatureFormatter(rsa);
 132                         f.SetHashAlgorithm("SslHash");
 133
 134                         return f.CreateSignature(this.Hash);
 135                 }
 136
 137                 public bool VerifySignature(RSA rsa, byte[] rgbSignature)
 138                 {
 139                         if (rsa == null)
 140                         {
 141                                 throw new CryptographicUnexpectedOperationException ("missing key");
 142                         }
 143                         if (rgbSignature == null)
 144                         {
 145                                 throw new ArgumentNullException ("rgbSignature");
 146                         }
 147
 148                         RSASslSignatureDeformatter d = new RSASslSignatureDeformatter(rsa);
 149                         d.SetHashAlgorithm("SslHash");
 150
 151                         return d.VerifySignature(this.Hash, rgbSignature);
 152                 }
 153
 154                 #endregion
 155
 156                 #region Private Methods
 157
 158                 private void initializePad()
 159                 {
 160                         // Fill md5 arrays
 161                         this.innerPadMD5 = new byte[48];
 162                         this.outerPadMD5 = new byte[48];
 163
 164                         /* Pad the key for inner and outer digest */
 165                         for (int i = 0; i < 48; ++i)
 166                         {
 167                                 this.innerPadMD5[i] = 0x36;
 168                                 this.outerPadMD5[i] = 0x5C;
 169                         }
 170
 171                         // Fill sha arrays
 172                         this.innerPadSHA = new byte[40];
 173                         this.outerPadSHA = new byte[40];
 174
 175                         /* Pad the key for inner and outer digest */
 176                         for (int i = 0; i < 40; ++i)
 177                         {
 178                                 this.innerPadSHA[i] = 0x36;
 179                                 this.outerPadSHA[i] = 0x5C;
 180                         }
 181                 }
 182
 183                 #endregion
 184         }
 185 }