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

   1 //
   2 // RSACryptoServiceProvider.cs: Handles an RSA implementation.
   3 //
   4 // Authors:
   5 //      Sebastien Pouliot <sebastien@ximian.com>
   6 //      Ben Maurer (bmaurer@users.sf.net)
   7 //
   8 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
   9 // Portions (C) 2003 Ben Maurer
  10 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 #if !NET_2_1 || MONOTOUCH
  33
  34 using System.IO;
  35 using System.Runtime.InteropServices;
  36
  37 using Mono.Security.Cryptography;
  38
  39 namespace System.Security.Cryptography {
  40
  41 #if NET_2_0
  42         [ComVisible (true)]
  43         public sealed class RSACryptoServiceProvider : RSA, ICspAsymmetricAlgorithm {
  44 #else
  45         public sealed class RSACryptoServiceProvider : RSA {
  46 #endif
  47                 private const int PROV_RSA_FULL = 1;    // from WinCrypt.h
  48
  49                 private KeyPairPersistence store;
  50                 private bool persistKey;
  51                 private bool persisted;
  52
  53                 private bool privateKeyExportable = true;
  54                 private bool m_disposed;
  55
  56                 private RSAManaged rsa;
  57
  58                 public RSACryptoServiceProvider ()
  59                 {
  60                         // Here it's not clear if we need to generate a keypair
  61                         // (note: MS implementation generates a keypair in this case).
  62                         // However we:
  63                         // (a) often use this constructor to import an existing keypair.
  64                         // (b) take a LOT of time to generate the RSA keypair
  65                         // So we'll generate the keypair only when (and if) it's being
  66                         // used (or exported). This should save us a lot of time (at
  67                         // least in the unit tests).
  68                         Common (1024, null);
  69                 }
  70
  71                 public RSACryptoServiceProvider (CspParameters parameters)
  72                 {
  73                         Common (1024, parameters);
  74                         // no keypair generation done at this stage
  75                 }
  76
  77                 public RSACryptoServiceProvider (int dwKeySize)
  78                 {
  79                         // Here it's clear that we need to generate a new keypair
  80                         Common (dwKeySize, null);
  81                         // no keypair generation done at this stage
  82                 }
  83
  84                 public RSACryptoServiceProvider (int dwKeySize, CspParameters parameters)
  85                 {
  86                         Common (dwKeySize, parameters);
  87                         // no keypair generation done at this stage
  88                 }
  89
  90                 private void Common (int dwKeySize, CspParameters p)
  91                 {
  92                         // Microsoft RSA CSP can do between 384 and 16384 bits keypair
  93                         LegalKeySizesValue = new KeySizes [1];
  94                         LegalKeySizesValue [0] = new KeySizes (384, 16384, 8);
  95                         base.KeySize = dwKeySize;
  96
  97                         rsa = new RSAManaged (KeySize);
  98                         rsa.KeyGenerated += new RSAManaged.KeyGeneratedEventHandler (OnKeyGenerated);
  99
 100                         persistKey = (p != null);
 101                         if (p == null) {
 102                                 p = new CspParameters (PROV_RSA_FULL);
 103 #if NET_1_1
 104                                 if (useMachineKeyStore)
 105                                         p.Flags |= CspProviderFlags.UseMachineKeyStore;
 106 #endif
 107                                 store = new KeyPairPersistence (p);
 108                                 // no need to load - it cannot exists
 109                         }
 110                         else {
 111                                 store = new KeyPairPersistence (p);
 112                                 store.Load ();
 113                                 if (store.KeyValue != null) {
 114                                         persisted = true;
 115                                         this.FromXmlString (store.KeyValue);
 116                                 }
 117                         }
 118                 }
 119
 120 #if NET_1_1
 121                 private static bool useMachineKeyStore = false;
 122
 123                 public static bool UseMachineKeyStore {
 124                         get { return useMachineKeyStore; }
 125                         set { useMachineKeyStore = value; }
 126                 }
 127 #endif
 128
 129                 ~RSACryptoServiceProvider ()
 130                 {
 131                         // Zeroize private key
 132                         Dispose (false);
 133                 }
 134
 135                 public override string KeyExchangeAlgorithm {
 136                         get { return "RSA-PKCS1-KeyEx"; }
 137                 }
 138
 139                 public override int KeySize {
 140                         get {
 141                                 if (rsa == null)
 142                                       return KeySizeValue;
 143                                 else
 144                                       return rsa.KeySize;
 145                         }
 146                 }
 147
 148                 public bool PersistKeyInCsp {
 149                         get { return persistKey; }
 150                         set {
 151                                 persistKey = value;
 152                                 if (persistKey)
 153                                         OnKeyGenerated (rsa, null);
 154                         }
 155                 }
 156
 157 #if (NET_2_0)
 158                 [ComVisible (false)]
 159                 public
 160 #else
 161                 internal
 162 #endif
 163                 bool PublicOnly {
 164                         get { return rsa.PublicOnly; }
 165                 }
 166
 167                 public override string SignatureAlgorithm {
 168                         get { return "http://www.w3.org/2000/09/xmldsig#rsa-sha1"; }
 169                 }
 170
 171                 public byte[] Decrypt (byte[] rgb, bool fOAEP)
 172                 {
 173 #if NET_1_1
 174                         if (m_disposed)
 175                                 throw new ObjectDisposedException ("rsa");
 176 #endif
 177                         // choose between OAEP or PKCS#1 v.1.5 padding
 178                         AsymmetricKeyExchangeDeformatter def = null;
 179                         if (fOAEP)
 180                                 def = new RSAOAEPKeyExchangeDeformatter (rsa);
 181                         else
 182                                 def = new RSAPKCS1KeyExchangeDeformatter (rsa);
 183
 184                         return def.DecryptKeyExchange (rgb);
 185                 }
 186
 187                 // NOTE: Unlike MS we need this method
 188                 // LAMESPEC: Not available from MS .NET framework but MS don't tell
 189                 // why! DON'T USE IT UNLESS YOU KNOW WHAT YOU ARE DOING!!! You should
 190                 // only encrypt/decrypt session (secret) key using asymmetric keys.
 191                 // Using this method to decrypt data IS dangerous (and very slow).
 192                 public override byte[] DecryptValue (byte[] rgb)
 193                 {
 194                         if (!rsa.IsCrtPossible)
 195                                 throw new CryptographicException ("Incomplete private key - missing CRT.");
 196
 197                         return rsa.DecryptValue (rgb);
 198                 }
 199
 200                 public byte[] Encrypt (byte[] rgb, bool fOAEP)
 201                 {
 202                         // choose between OAEP or PKCS#1 v.1.5 padding
 203                         AsymmetricKeyExchangeFormatter fmt = null;
 204                         if (fOAEP)
 205                                 fmt = new RSAOAEPKeyExchangeFormatter (rsa);
 206                         else
 207                                 fmt = new RSAPKCS1KeyExchangeFormatter (rsa);
 208
 209                         return fmt.CreateKeyExchange (rgb);
 210                 }
 211
 212                 // NOTE: Unlike MS we need this method
 213                 // LAMESPEC: Not available from MS .NET framework but MS don't tell
 214                 // why! DON'T USE IT UNLESS YOU KNOW WHAT YOU ARE DOING!!! You should
 215                 // only encrypt/decrypt session (secret) key using asymmetric keys.
 216                 // Using this method to encrypt data IS dangerous (and very slow).
 217                 public override byte[] EncryptValue (byte[] rgb)
 218                 {
 219                         return rsa.EncryptValue (rgb);
 220                 }
 221
 222                 public override RSAParameters ExportParameters (bool includePrivateParameters)
 223                 {
 224                         if ((includePrivateParameters) && (!privateKeyExportable))
 225                                 throw new CryptographicException ("cannot export private key");
 226
 227                         return rsa.ExportParameters (includePrivateParameters);
 228                 }
 229
 230                 public override void ImportParameters (RSAParameters parameters)
 231                 {
 232                         rsa.ImportParameters (parameters);
 233                 }
 234
 235                 private HashAlgorithm GetHash (object halg)
 236                 {
 237                         if (halg == null)
 238                                 throw new ArgumentNullException ("halg");
 239
 240                         HashAlgorithm hash = null;
 241                         if (halg is String)
 242                                 hash = HashAlgorithm.Create ((String)halg);
 243                         else if (halg is HashAlgorithm)
 244                                 hash = (HashAlgorithm) halg;
 245                         else if (halg is Type)
 246                                 hash = (HashAlgorithm) Activator.CreateInstance ((Type)halg);
 247                         else
 248                                 throw new ArgumentException ("halg");
 249
 250                         return hash;
 251                 }
 252
 253                 // NOTE: this method can work with ANY configured (OID in machine.config)
 254                 // HashAlgorithm descendant
 255                 public byte[] SignData (byte[] buffer, object halg)
 256                 {
 257 #if NET_1_1
 258                         if (buffer == null)
 259                                 throw new ArgumentNullException ("buffer");
 260 #endif
 261                         return SignData (buffer, 0, buffer.Length, halg);
 262                 }
 263
 264                 // NOTE: this method can work with ANY configured (OID in machine.config)
 265                 // HashAlgorithm descendant
 266                 public byte[] SignData (Stream inputStream, object halg)
 267                 {
 268                         HashAlgorithm hash = GetHash (halg);
 269                         byte[] toBeSigned = hash.ComputeHash (inputStream);
 270                         return PKCS1.Sign_v15 (this, hash, toBeSigned);
 271                 }
 272
 273                 // NOTE: this method can work with ANY configured (OID in machine.config)
 274                 // HashAlgorithm descendant
 275                 public byte[] SignData (byte[] buffer, int offset, int count, object halg)
 276                 {
 277                         HashAlgorithm hash = GetHash (halg);
 278                         byte[] toBeSigned = hash.ComputeHash (buffer, offset, count);
 279                         return PKCS1.Sign_v15 (this, hash, toBeSigned);
 280                 }
 281
 282                 private string GetHashNameFromOID (string oid)
 283                 {
 284                         switch (oid) {
 285                                 case "1.3.14.3.2.26":
 286                                         return "SHA1";
 287                                 case "1.2.840.113549.2.5":
 288                                         return "MD5";
 289                                 default:
 290                                         throw new NotSupportedException (oid + " is an unsupported hash algorithm for RSA signing");
 291                         }
 292                 }
 293
 294                 // LAMESPEC: str is not the hash name but an OID
 295                 // NOTE: this method is LIMITED to SHA1 and MD5 like the MS framework 1.0
 296                 // and 1.1 because there's no method to get a hash algorithm from an OID.
 297                 // However there's no such limit when using the [De]Formatter class.
 298                 public byte[] SignHash (byte[] rgbHash, string str)
 299                 {
 300                         if (rgbHash == null)
 301                                 throw new ArgumentNullException ("rgbHash");
 302 #if NET_2_0
 303                         // Fx 2.0 defaults to the SHA-1
 304                         string hashName = (str == null) ? "SHA1" : GetHashNameFromOID (str);
 305 #else
 306                         if (str == null)
 307                                 throw new CryptographicException (Locale.GetText ("No OID specified"));
 308                         string hashName = GetHashNameFromOID (str);
 309 #endif
 310                         HashAlgorithm hash = HashAlgorithm.Create (hashName);
 311                         return PKCS1.Sign_v15 (this, hash, rgbHash);
 312                 }
 313
 314                 // NOTE: this method can work with ANY configured (OID in machine.config)
 315                 // HashAlgorithm descendant
 316                 public bool VerifyData (byte[] buffer, object halg, byte[] signature)
 317                 {
 318 #if NET_1_1
 319                         if (buffer == null)
 320                                 throw new ArgumentNullException ("buffer");
 321 #endif
 322                         if (signature == null)
 323                                 throw new ArgumentNullException ("signature");
 324
 325                         HashAlgorithm hash = GetHash (halg);
 326                         byte[] toBeVerified = hash.ComputeHash (buffer);
 327                         return PKCS1.Verify_v15 (this, hash, toBeVerified, signature);
 328                 }
 329
 330                 // LAMESPEC: str is not the hash name but an OID
 331                 // NOTE: this method is LIMITED to SHA1 and MD5 like the MS framework 1.0
 332                 // and 1.1 because there's no method to get a hash algorithm from an OID.
 333                 // However there's no such limit when using the [De]Formatter class.
 334                 public bool VerifyHash (byte[] rgbHash, string str, byte[] rgbSignature)
 335                 {
 336                         if (rgbHash == null)
 337                                 throw new ArgumentNullException ("rgbHash");
 338                         if (rgbSignature == null)
 339                                 throw new ArgumentNullException ("rgbSignature");
 340 #if NET_2_0
 341                         // Fx 2.0 defaults to the SHA-1
 342                         string hashName = (str == null) ? "SHA1" : GetHashNameFromOID (str);
 343 #else
 344                         if (str == null)
 345                                 throw new CryptographicException (Locale.GetText ("No OID specified"));
 346                         string hashName = GetHashNameFromOID (str);
 347 #endif
 348                         HashAlgorithm hash = HashAlgorithm.Create (hashName);
 349                         return PKCS1.Verify_v15 (this, hash, rgbHash, rgbSignature);
 350                 }
 351
 352                 protected override void Dispose (bool disposing)
 353                 {
 354                         if (!m_disposed) {
 355                                 // the key is persisted and we do not want it persisted
 356                                 if ((persisted) && (!persistKey)) {
 357                                         store.Remove ();        // delete the container
 358                                 }
 359                                 if (rsa != null)
 360                                         rsa.Clear ();
 361                                 // call base class
 362                                 // no need as they all are abstract before us
 363                                 m_disposed = true;
 364                         }
 365                 }
 366
 367                 // private stuff
 368
 369                 private void OnKeyGenerated (object sender, EventArgs e)
 370                 {
 371                         // the key isn't persisted and we want it persisted
 372                         if ((persistKey) && (!persisted)) {
 373                                 // save the current keypair
 374                                 store.KeyValue = this.ToXmlString (!rsa.PublicOnly);
 375                                 store.Save ();
 376                                 persisted = true;
 377                         }
 378                 }
 379 #if NET_2_0
 380                 // ICspAsymmetricAlgorithm
 381
 382                 [MonoTODO ("Always return null")]
 383                 // FIXME: call into KeyPairPersistence to get details
 384                 [ComVisible (false)]
 385                 public CspKeyContainerInfo CspKeyContainerInfo {
 386                         get { return null; }
 387                 }
 388
 389                 [ComVisible (false)]
 390                 public byte[] ExportCspBlob (bool includePrivateParameters)
 391                 {
 392                         byte[] blob = null;
 393                         if (includePrivateParameters)
 394                                 blob = CryptoConvert.ToCapiPrivateKeyBlob (this);
 395                         else
 396                                 blob = CryptoConvert.ToCapiPublicKeyBlob (this);
 397
 398                         // ALGID (bytes 4-7) - default is KEYX
 399                         // 00 24 00 00 (for CALG_RSA_SIGN)
 400                         // 00 A4 00 00 (for CALG_RSA_KEYX)
 401                         blob [5] = 0xA4;
 402                         return blob;
 403                 }
 404
 405                 [ComVisible (false)]
 406                 public void ImportCspBlob (byte[] keyBlob)
 407                 {
 408                         if (keyBlob == null)
 409                                 throw new ArgumentNullException ("keyBlob");
 410
 411                         RSA rsa = CryptoConvert.FromCapiKeyBlob (keyBlob);
 412                         if (rsa is RSACryptoServiceProvider) {
 413                                 // default (if no change are present in machine.config)
 414                                 RSAParameters rsap = rsa.ExportParameters (!(rsa as RSACryptoServiceProvider).PublicOnly);
 415                                 ImportParameters (rsap);
 416                         } else {
 417                                 // we can't know from RSA if the private key is available
 418                                 try {
 419                                         // so we try it...
 420                                         RSAParameters rsap = rsa.ExportParameters (true);
 421                                         ImportParameters (rsap);
 422                                 }
 423                                 catch {
 424                                         // and fall back
 425                                         RSAParameters rsap = rsa.ExportParameters (false);
 426                                         ImportParameters (rsap);
 427                                 }
 428                         }
 429                 }
 430 #endif
 431         }
 432 }
 433
 434 #endif
 435