mcs/class/corlib/System.Security.Cryptography/HMACSHA1.cs

   1 //
   2 // HMACSHA1.cs: Handles HMAC with SHA-1
   3 //
   4 // Author:
   5 //      Sebastien Pouliot <sebastien@ximian.com>
   6 //
   7 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.IO;
  31
  32 using Mono.Security.Cryptography;
  33
  34 namespace System.Security.Cryptography {
  35
  36         // References:
  37         // a.   FIPS PUB 198: The Keyed-Hash Message Authentication Code (HMAC), 2002 March.
  38         //      http://csrc.nist.gov/publications/fips/fips198/fips-198a.pdf
  39         // b.   Internet RFC 2104, HMAC, Keyed-Hashing for Message Authentication
  40         //      (include C source for HMAC-MD5)
  41         //      http://www.ietf.org/rfc/rfc2104.txt
  42         // c.   IETF RFC2202: Test Cases for HMAC-MD5 and HMAC-SHA-1
  43         //      (include C source for HMAC-MD5 and HAMAC-SHA1)
  44         //      http://www.ietf.org/rfc/rfc2202.txt
  45         // d.   ANSI X9.71, Keyed Hash Message Authentication Code.
  46         //      not free :-(
  47         //      http://webstore.ansi.org/ansidocstore/product.asp?sku=ANSI+X9%2E71%2D2000
  48
  49 #if ! NET_2_0
  50         public class HMACSHA1: KeyedHashAlgorithm {
  51                 private HMACAlgorithm hmac;
  52                 private bool m_disposed;
  53
  54                 public HMACSHA1 () : this (KeyBuilder.Key (8))
  55                 {
  56                 }
  57
  58                 public HMACSHA1 (byte[] rgbKey) : base ()
  59                 {
  60                         hmac = new HMACAlgorithm ("SHA1");
  61                         HashSizeValue = 160;
  62                         Key = rgbKey;
  63                         m_disposed = false;
  64                 }
  65
  66                 ~HMACSHA1 ()
  67                 {
  68                         Dispose (false);
  69                 }
  70
  71                 public override byte[] Key {
  72                         get { return base.Key; }
  73                         set {
  74                                 hmac.Key = value;
  75                                 base.Key = value;
  76                         }
  77                 }
  78
  79                 public string HashName {
  80                         get { return hmac.HashName; }
  81                         set {
  82                                 // only if its not too late for a change
  83                                 if (State == 0)
  84                                         hmac.HashName = value;
  85                         }
  86                 }
  87
  88                 protected override void Dispose (bool disposing)
  89                 {
  90                         if (!m_disposed) {
  91                                 if (hmac != null)
  92                                         hmac.Dispose();
  93                                 base.Dispose (disposing);
  94                                 m_disposed = true;
  95                         }
  96                 }
  97
  98                 public override void Initialize ()
  99                 {
 100                         if (m_disposed)
 101                                 throw new ObjectDisposedException ("HMACSHA1");
 102                         // let us throw an exception if hash name is invalid
 103                         // for HMACSHA1 (obviously this can't be done by the
 104                         // generic HMAC class)
 105                         if (!(hmac.Algo is SHA1)) {
 106                                 string algo = (hmac.Algo == null) ? "none" : hmac.Algo.GetType ().ToString ();
 107                                 string msg = Locale.GetText ("Invalid hash algorithm '{0}', expected '{1}'.");
 108                                 throw new InvalidCastException (String.Format (msg, algo, "SHA1"));
 109                         }
 110                         State = 0;
 111                         hmac.Initialize ();
 112                 }
 113
 114                 protected override void HashCore (byte[] rgb, int ib, int cb)
 115                 {
 116                         if (m_disposed)
 117                                 throw new ObjectDisposedException ("HMACSHA1");
 118
 119                         if (State == 0) {
 120                                 Initialize ();
 121                                 State = 1;
 122                         }
 123                         hmac.Core (rgb, ib, cb);
 124                 }
 125
 126                 protected override byte[] HashFinal ()
 127                 {
 128                         if (m_disposed)
 129                                 throw new ObjectDisposedException ("HMACSHA1");
 130
 131                         State = 0;
 132                         return hmac.Final ();
 133                 }
 134         }
 135 #else
 136         public class HMACSHA1 : HMAC {
 137
 138                 public HMACSHA1 () : this (KeyBuilder.Key (8))
 139                 {
 140                 }
 141
 142                 public HMACSHA1 (byte[] rgbKey) : base ()
 143                 {
 144                         HashName = "SHA1";
 145                         HashSizeValue = 160;
 146                         Key = rgbKey;
 147                 }
 148
 149                 ~HMACSHA1 ()
 150                 {
 151                         Dispose (false);
 152                 }
 153         }
 154 #endif
 155 }