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

   1 //
   2 // System.Security.Cryptography.DSACryptoServiceProvider.cs
   3 //
   4 // Authors:
   5 //      Dan Lewis (dihlewis@yahoo.co.uk)
   6 //      Sebastien Pouliot <sebastien@ximian.com>
   7 //      Ben Maurer (bmaurer@users.sf.net)
   8 //
   9 // (C) 2002
  10 // Portions (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
  11 // Portions (C) 2003 Ben Maurer
  12 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System.IO;
  35 using System.Globalization;
  36 using System.Runtime.InteropServices;
  37
  38 using Mono.Security.Cryptography;
  39
  40 namespace System.Security.Cryptography {
  41
  42 #if NET_2_0
  43         public sealed class DSACryptoServiceProvider : DSA, ICspAsymmetricAlgorithm {
  44 #elif NET_1_1
  45         public sealed class DSACryptoServiceProvider : DSA {
  46 #else
  47         public class DSACryptoServiceProvider : DSA {
  48 #endif
  49                 private const int PROV_DSS_DH = 13;             // from WinCrypt.h
  50
  51                 private KeyPairPersistence store;
  52                 private bool persistKey;
  53                 private bool persisted;
  54
  55                 private bool privateKeyExportable = true;
  56                 private bool m_disposed;
  57
  58                 private DSAManaged dsa;
  59
  60                 // MS implementation generates a keypair everytime a new DSA
  61                 // object is created (unless an existing key container is
  62                 // specified in the CspParameters).
  63                 // However we:
  64                 // (a) often use DSA to import an existing keypair.
  65                 // (b) take a LOT of time to generate the DSA group
  66                 // So we'll generate the keypair only when (and if) it's being
  67                 // used (or exported). This should save us a lot of time (at
  68                 // least in the unit tests).
  69
  70                 public DSACryptoServiceProvider ()
  71                         : this (1024, null)
  72                 {
  73                 }
  74
  75                 public DSACryptoServiceProvider (CspParameters parameters)
  76                         : this (1024, parameters)
  77                 {
  78                 }
  79
  80                 public DSACryptoServiceProvider (int dwKeySize)
  81                         : this (dwKeySize, null)
  82                 {
  83                 }
  84
  85                 public DSACryptoServiceProvider (int dwKeySize, CspParameters parameters)
  86                 {
  87                         LegalKeySizesValue = new KeySizes [1];
  88                         LegalKeySizesValue [0] = new KeySizes (512, 1024, 64);
  89
  90                         // will throw an exception is key size isn't supported
  91                         KeySize = dwKeySize;
  92                         dsa = new DSAManaged (dwKeySize);
  93                         dsa.KeyGenerated += new DSAManaged.KeyGeneratedEventHandler (OnKeyGenerated);
  94
  95                         persistKey = (parameters != null);
  96                         if (parameters == null) {
  97                                 parameters = new CspParameters (PROV_DSS_DH);
  98 #if NET_1_1
  99                                 if (useMachineKeyStore)
 100                                         parameters.Flags |= CspProviderFlags.UseMachineKeyStore;
 101 #endif
 102                                 store = new KeyPairPersistence (parameters);
 103                                 // no need to load - it cannot exists
 104                         }
 105                         else {
 106                                 store = new KeyPairPersistence (parameters);
 107                                 store.Load ();
 108                                 if (store.KeyValue != null) {
 109                                         persisted = true;
 110                                         this.FromXmlString (store.KeyValue);
 111                                 }
 112                         }
 113                 }
 114
 115                 ~DSACryptoServiceProvider ()
 116                 {
 117                         Dispose (false);
 118                 }
 119
 120                 // DSA isn't used for key exchange
 121                 public override string KeyExchangeAlgorithm {
 122                         get { return null; }
 123                 }
 124
 125                 public override int KeySize {
 126                         get { return dsa.KeySize; }
 127                 }
 128
 129 #if !NET_2_0
 130                 public override KeySizes[] LegalKeySizes {
 131                         get { return LegalKeySizesValue; }
 132                 }
 133 #endif
 134
 135                 public bool PersistKeyInCsp {
 136                         get { return persistKey; }
 137                         set { persistKey = value; }
 138                 }
 139
 140 #if NET_2_0
 141                 [ComVisible (false)]
 142                 public
 143 #else
 144                 internal
 145 #endif
 146                 bool PublicOnly {
 147                         get { return dsa.PublicOnly; }
 148                 }
 149
 150                 public override string SignatureAlgorithm {
 151                         get { return "http://www.w3.org/2000/09/xmldsig#dsa-sha1"; }
 152                 }
 153
 154 #if NET_1_1
 155                 private static bool useMachineKeyStore = false;
 156
 157                 public static bool UseMachineKeyStore {
 158                         get { return useMachineKeyStore; }
 159                         set { useMachineKeyStore = value; }
 160                 }
 161 #endif
 162
 163                 public override DSAParameters ExportParameters (bool includePrivateParameters)
 164                 {
 165                         if ((includePrivateParameters) && (!privateKeyExportable)) {
 166                                 throw new CryptographicException (
 167                                         Locale.GetText ("Cannot export private key"));
 168                         }
 169
 170                         return dsa.ExportParameters (includePrivateParameters);
 171                 }
 172
 173                 public override void ImportParameters (DSAParameters parameters)
 174                 {
 175                         dsa.ImportParameters (parameters);
 176                 }
 177
 178                 public override byte[] CreateSignature (byte[] rgbHash)
 179                 {
 180                         return dsa.CreateSignature (rgbHash);
 181                 }
 182
 183                 public byte[] SignData (byte[] data)
 184                 {
 185                         // right now only SHA1 is supported by FIPS186-2
 186                         HashAlgorithm hash = SHA1.Create ();
 187                         byte[] toBeSigned = hash.ComputeHash (data);
 188                         return dsa.CreateSignature (toBeSigned);
 189                 }
 190
 191                 public byte[] SignData (byte[] data, int offset, int count)
 192                 {
 193                         // right now only SHA1 is supported by FIPS186-2
 194                         HashAlgorithm hash = SHA1.Create ();
 195                         byte[] toBeSigned = hash.ComputeHash (data, offset, count);
 196                         return dsa.CreateSignature (toBeSigned);
 197                 }
 198
 199                 public byte[] SignData (Stream inputStream)
 200                 {
 201                         // right now only SHA1 is supported by FIPS186-2
 202                         HashAlgorithm hash = SHA1.Create ();
 203                         byte[] toBeSigned = hash.ComputeHash (inputStream);
 204                         return dsa.CreateSignature (toBeSigned);
 205                 }
 206
 207                 public byte[] SignHash (byte[] rgbHash, string str)
 208                 {
 209                         // right now only SHA1 is supported by FIPS186-2
 210                         if (String.Compare (str, "SHA1", true, CultureInfo.InvariantCulture) != 0) {
 211                                 // not documented
 212                                 throw new CryptographicException (Locale.GetText ("Only SHA1 is supported."));
 213                         }
 214
 215                         return dsa.CreateSignature (rgbHash);
 216                 }
 217
 218                 public bool VerifyData (byte[] rgbData, byte[] rgbSignature)
 219                 {
 220                         // right now only SHA1 is supported by FIPS186-2
 221                         HashAlgorithm hash = SHA1.Create();
 222                         byte[] toBeVerified = hash.ComputeHash (rgbData);
 223                         return dsa.VerifySignature (toBeVerified, rgbSignature);
 224                 }
 225
 226                 // LAMESPEC: MD5 isn't allowed with DSA
 227                 public bool VerifyHash (byte[] rgbHash, string str, byte[] rgbSignature)
 228                 {
 229                         if (str == null)
 230                                 str = "SHA1"; // default value
 231                         if (String.Compare (str, "SHA1", true, CultureInfo.InvariantCulture) != 0) {
 232                                 throw new CryptographicException (Locale.GetText ("Only SHA1 is supported."));
 233                         }
 234
 235                         return dsa.VerifySignature (rgbHash, rgbSignature);
 236                 }
 237
 238                 public override bool VerifySignature (byte[] rgbHash, byte[] rgbSignature)
 239                 {
 240                         return dsa.VerifySignature (rgbHash, rgbSignature);
 241                 }
 242
 243                 protected override void Dispose (bool disposing)
 244                 {
 245                         if (!m_disposed) {
 246                                 // the key is persisted and we do not want it persisted
 247                                 if ((persisted) && (!persistKey)) {
 248                                         store.Remove ();        // delete the container
 249                                 }
 250                                 if (dsa != null)
 251                                         dsa.Clear ();
 252                                 // call base class
 253                                 // no need as they all are abstract before us
 254                                 m_disposed = true;
 255                         }
 256                 }
 257
 258                 // private stuff
 259
 260                 private void OnKeyGenerated (object sender, EventArgs e)
 261                 {
 262                         // the key isn't persisted and we want it persisted
 263                         if ((persistKey) && (!persisted)) {
 264                                 // save the current keypair
 265                                 store.KeyValue = this.ToXmlString (!dsa.PublicOnly);
 266                                 store.Save ();
 267                                 persisted = true;
 268                         }
 269                 }
 270 #if NET_2_0
 271                 // ICspAsymmetricAlgorithm
 272
 273                 [MonoTODO ("call into KeyPairPersistence to get details")]
 274                 [ComVisible (false)]
 275                 public CspKeyContainerInfo CspKeyContainerInfo {
 276                         get { return null; }
 277                 }
 278
 279                 [MonoTODO ("call into CryptoConvert (doesn't currently support DSA)")]
 280                 [ComVisible (false)]
 281                 public byte[] ExportCspBlob (bool includePrivateParameters)
 282                 {
 283                         throw new NotImplementedException ("CryptoConvert doesn't currently support DSA");
 284                 }
 285
 286                 [MonoTODO ("call into CryptoConvert (doesn't currently support DSA)")]
 287                 [ComVisible (false)]
 288                 public void ImportCspBlob (byte[] rawData)
 289                 {
 290                         if (rawData == null)
 291                                 throw new ArgumentNullException ("rawData");
 292                         throw new NotImplementedException ("CryptoConvert doesn't currently support DSA");
 293                 }
 294 #endif
 295         }
 296 }