mcs/class/Mono.Security/Mono.Security.Cryptography/PKCS8.cs

   1 //
   2 // PKCS8.cs: PKCS #8 - Private-Key Information Syntax Standard
   3 //      ftp://ftp.rsasecurity.com/pub/pkcs/doc/pkcs-8.doc
   4 //
   5 // Author:
   6 //      Sebastien Pouliot <sebastien@ximian.com>
   7 //
   8 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   9 // (C) 2004 Novell (http://www.novell.com)
  10 //
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Collections;
  35 using System.Security.Cryptography;
  36 using System.Text;
  37
  38 using Mono.Security.Cryptography;
  39 using Mono.Security.X509;
  40
  41 namespace Mono.Security.Cryptography {
  42
  43         public sealed class PKCS8 {
  44
  45                 public enum KeyInfo {
  46                         PrivateKey,
  47                         EncryptedPrivateKey,
  48                         Unknown
  49                 }
  50
  51                 private PKCS8 ()
  52                 {
  53                 }
  54
  55                 static public KeyInfo GetType (byte[] data)
  56                 {
  57                         if (data == null)
  58                                 throw new ArgumentNullException ("data");
  59
  60                         KeyInfo ki = KeyInfo.Unknown;
  61                         try {
  62                                 ASN1 top = new ASN1 (data);
  63                                 if ((top.Tag == 0x30) && (top.Count > 0)) {
  64                                         ASN1 firstLevel = top [0];
  65                                         switch (firstLevel.Tag) {
  66                                                 case 0x02:
  67                                                         ki = KeyInfo.PrivateKey;
  68                                                         break;
  69                                                 case 0x30:
  70                                                         ki = KeyInfo.EncryptedPrivateKey;
  71                                                         break;
  72                                         }
  73                                 }
  74                         }
  75                         catch {
  76                                 throw new CryptographicException ("invalid ASN.1 data");
  77                         }
  78                         return ki;
  79                 }
  80
  81                 /*
  82                  * PrivateKeyInfo ::= SEQUENCE {
  83                  *      version Version,
  84                  *      privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
  85                  *      privateKey PrivateKey,
  86                  *      attributes [0] IMPLICIT Attributes OPTIONAL
  87                  * }
  88                  *
  89                  * Version ::= INTEGER
  90                  *
  91                  * PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
  92                  *
  93                  * PrivateKey ::= OCTET STRING
  94                  *
  95                  * Attributes ::= SET OF Attribute
  96                  */
  97                 public class PrivateKeyInfo {
  98
  99                         private int _version;
 100                         private string _algorithm;
 101                         private byte[] _key;
 102                         private ArrayList _list;
 103
 104                         public PrivateKeyInfo ()
 105                         {
 106                                 _version = 0;
 107                                 _list = new ArrayList ();
 108                         }
 109
 110                         public PrivateKeyInfo (byte[] data) : this ()
 111                         {
 112                                 Decode (data);
 113                         }
 114
 115                         // properties
 116
 117                         public string Algorithm {
 118                                 get { return _algorithm; }
 119                                 set { _algorithm = value; }
 120                         }
 121
 122                         public ArrayList Attributes {
 123                                 get { return _list; }
 124                         }
 125
 126                         public byte[] PrivateKey {
 127                                 get {
 128                                         if (_key == null)
 129                                                 return null;
 130                                         return (byte[]) _key.Clone ();
 131                                 }
 132                                 set {
 133                                         if (value == null)
 134                                                 throw new ArgumentNullException ("PrivateKey");
 135                                         _key = (byte[]) value.Clone ();
 136                                 }
 137                         }
 138
 139                         public int Version {
 140                                 get { return _version; }
 141                                 set {
 142                                         if (value < 0)
 143                                                 throw new ArgumentOutOfRangeException ("negative version");
 144                                         _version = value;
 145                                 }
 146                         }
 147
 148                         // methods
 149
 150                         private void Decode (byte[] data)
 151                         {
 152                                 ASN1 privateKeyInfo = new ASN1 (data);
 153                                 if (privateKeyInfo.Tag != 0x30)
 154                                         throw new CryptographicException ("invalid PrivateKeyInfo");
 155
 156                                 ASN1 version = privateKeyInfo [0];
 157                                 if (version.Tag != 0x02)
 158                                         throw new CryptographicException ("invalid version");
 159                                 _version = version.Value [0];
 160
 161                                 ASN1 privateKeyAlgorithm = privateKeyInfo [1];
 162                                 if (privateKeyAlgorithm.Tag != 0x30)
 163                                         throw new CryptographicException ("invalid algorithm");
 164
 165                                 ASN1 algorithm = privateKeyAlgorithm [0];
 166                                 if (algorithm.Tag != 0x06)
 167                                         throw new CryptographicException ("missing algorithm OID");
 168                                 _algorithm = ASN1Convert.ToOid (algorithm);
 169
 170                                 ASN1 privateKey = privateKeyInfo [2];
 171                                 _key = privateKey.Value;
 172
 173                                 // attributes [0] IMPLICIT Attributes OPTIONAL
 174                                 if (privateKeyInfo.Count > 3) {
 175                                         ASN1 attributes = privateKeyInfo [3];
 176                                         for (int i=0; i < attributes.Count; i++) {
 177                                                 _list.Add (attributes [i]);
 178                                         }
 179                                 }
 180                         }
 181
 182                         public byte[] GetBytes ()
 183                         {
 184                                 ASN1 privateKeyAlgorithm = new ASN1 (0x30);
 185                                 privateKeyAlgorithm.Add (ASN1Convert.FromOid (_algorithm));
 186                                 privateKeyAlgorithm.Add (new ASN1 (0x05)); // ASN.1 NULL
 187
 188                                 ASN1 pki = new ASN1 (0x30);
 189                                 pki.Add (new ASN1 (0x02, new byte [1] { (byte) _version }));
 190                                 pki.Add (privateKeyAlgorithm);
 191                                 pki.Add (new ASN1 (0x04, _key));
 192
 193                                 if (_list.Count > 0) {
 194                                         ASN1 attributes = new ASN1 (0xA0);
 195                                         foreach (ASN1 attribute in _list) {
 196                                                 attributes.Add (attribute);
 197                                         }
 198                                         pki.Add (attributes);
 199                                 }
 200
 201                                 return pki.GetBytes ();
 202                         }
 203
 204                         // static methods
 205
 206                         static private byte[] RemoveLeadingZero (byte[] bigInt)
 207                         {
 208                                 int start = 0;
 209                                 int length = bigInt.Length;
 210                                 if (bigInt [0] == 0x00) {
 211                                         start = 1;
 212                                         length--;
 213                                 }
 214                                 byte[] bi = new byte [length];
 215                                 Buffer.BlockCopy (bigInt, start, bi, 0, length);
 216                                 return bi;
 217                         }
 218
 219                         static private byte[] Normalize (byte[] bigInt, int length)
 220                         {
 221                                 if (bigInt.Length == length)
 222                                         return bigInt;
 223                                 else if (bigInt.Length > length)
 224                                         return RemoveLeadingZero (bigInt);
 225                                 else {
 226                                         // pad with 0
 227                                         byte[] bi = new byte [length];
 228                                         Buffer.BlockCopy (bigInt, 0, bi, (length - bigInt.Length), bigInt.Length);
 229                                         return bi;
 230                                 }
 231                         }
 232
 233                         /*
 234                          * RSAPrivateKey ::= SEQUENCE {
 235                          *      version           Version,
 236                          *      modulus           INTEGER,  -- n
 237                          *      publicExponent    INTEGER,  -- e
 238                          *      privateExponent   INTEGER,  -- d
 239                          *      prime1            INTEGER,  -- p
 240                          *      prime2            INTEGER,  -- q
 241                          *      exponent1         INTEGER,  -- d mod (p-1)
 242                          *      exponent2         INTEGER,  -- d mod (q-1)
 243                          *      coefficient       INTEGER,  -- (inverse of q) mod p
 244                          *      otherPrimeInfos   OtherPrimeInfos OPTIONAL
 245                          * }
 246                          */
 247                         static public RSA DecodeRSA (byte[] keypair)
 248                         {
 249                                 ASN1 privateKey = new ASN1 (keypair);
 250                                 if (privateKey.Tag != 0x30)
 251                                         throw new CryptographicException ("invalid private key format");
 252
 253                                 ASN1 version = privateKey [0];
 254                                 if (version.Tag != 0x02)
 255                                         throw new CryptographicException ("missing version");
 256
 257                                 if (privateKey.Count < 9)
 258                                         throw new CryptographicException ("not enough key parameters");
 259
 260                                 RSAParameters param = new RSAParameters ();
 261                                 // note: MUST remove leading 0 - else MS wont import the key
 262                                 param.Modulus = RemoveLeadingZero (privateKey [1].Value);
 263                                 int keysize = param.Modulus.Length;
 264                                 int keysize2 = (keysize >> 1); // half-size
 265                                 // size must be normalized - else MS wont import the key
 266                                 param.D = Normalize (privateKey [3].Value, keysize);
 267                                 param.DP = Normalize (privateKey [6].Value, keysize2);
 268                                 param.DQ = Normalize (privateKey [7].Value, keysize2);
 269                                 param.Exponent = RemoveLeadingZero (privateKey [2].Value);
 270                                 param.InverseQ = Normalize (privateKey [8].Value, keysize2);
 271                                 param.P = Normalize (privateKey [4].Value, keysize2);
 272                                 param.Q = Normalize (privateKey [5].Value, keysize2);
 273
 274                                 RSA rsa = RSA.Create ();
 275                                 rsa.ImportParameters (param);
 276                                 return rsa;
 277                         }
 278
 279                         /*
 280                          * RSAPrivateKey ::= SEQUENCE {
 281                          *      version           Version,
 282                          *      modulus           INTEGER,  -- n
 283                          *      publicExponent    INTEGER,  -- e
 284                          *      privateExponent   INTEGER,  -- d
 285                          *      prime1            INTEGER,  -- p
 286                          *      prime2            INTEGER,  -- q
 287                          *      exponent1         INTEGER,  -- d mod (p-1)
 288                          *      exponent2         INTEGER,  -- d mod (q-1)
 289                          *      coefficient       INTEGER,  -- (inverse of q) mod p
 290                          *      otherPrimeInfos   OtherPrimeInfos OPTIONAL
 291                          * }
 292                          */
 293                         static public byte[] Encode (RSA rsa)
 294                         {
 295                                 RSAParameters param = rsa.ExportParameters (true);
 296
 297                                 ASN1 rsaPrivateKey = new ASN1 (0x30);
 298                                 rsaPrivateKey.Add (new ASN1 (0x02, new byte [1] { 0x00 }));
 299                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.Modulus));
 300                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.Exponent));
 301                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.D));
 302                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.P));
 303                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.Q));
 304                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.DP));
 305                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.DQ));
 306                                 rsaPrivateKey.Add (ASN1Convert.FromUnsignedBigInteger (param.InverseQ));
 307
 308                                 return rsaPrivateKey.GetBytes ();
 309                         }
 310
 311                         // DSA only encode it's X private key inside an ASN.1 INTEGER (Hint: Tag == 0x02)
 312                         // which isn't enough for rebuilding the keypair. The other parameters
 313                         // can be found (98% of the time) in the X.509 certificate associated
 314                         // with the private key or (2% of the time) the parameters are in it's
 315                         // issuer X.509 certificate (not supported in the .NET framework).
 316                         static public DSA DecodeDSA (byte[] privateKey, DSAParameters dsaParameters)
 317                         {
 318                                 ASN1 pvk = new ASN1 (privateKey);
 319                                 if (pvk.Tag != 0x02)
 320                                         throw new CryptographicException ("invalid private key format");
 321
 322                                 // X is ALWAYS 20 bytes (no matter if the key length is 512 or 1024 bits)
 323                                 dsaParameters.X = Normalize (privateKey, 20);
 324                                 DSA dsa = DSA.Create ();
 325                                 dsa.ImportParameters (dsaParameters);
 326                                 return dsa;
 327                         }
 328
 329                         static public byte[] Encode (DSA dsa)
 330                         {
 331                                 DSAParameters param = dsa.ExportParameters (true);
 332                                 return ASN1Convert.FromUnsignedBigInteger (param.X).GetBytes ();
 333                         }
 334
 335                         static public byte[] Encode (AsymmetricAlgorithm aa)
 336                         {
 337                                 if (aa is RSA)
 338                                         return Encode ((RSA)aa);
 339                                 else if (aa is DSA)
 340                                         return Encode ((DSA)aa);
 341                                 else
 342                                         throw new CryptographicException ("Unknown asymmetric algorithm {0}", aa.ToString ());
 343                         }
 344                 }
 345
 346                 /*
 347                  * EncryptedPrivateKeyInfo ::= SEQUENCE {
 348                  *      encryptionAlgorithm EncryptionAlgorithmIdentifier,
 349                  *      encryptedData EncryptedData
 350                  * }
 351                  *
 352                  * EncryptionAlgorithmIdentifier ::= AlgorithmIdentifier
 353                  *
 354                  * EncryptedData ::= OCTET STRING
 355                  *
 356                  * --
 357                  *  AlgorithmIdentifier  ::= SEQUENCE {
 358                  *      algorithm  OBJECT IDENTIFIER,
 359                  *      parameters ANY DEFINED BY algorithm OPTIONAL
 360                  * }
 361                  *
 362                  * -- from PKCS#5
 363                  * PBEParameter ::= SEQUENCE {
 364                  *      salt OCTET STRING SIZE(8),
 365                  *      iterationCount INTEGER
 366                  * }
 367                  */
 368                 public class EncryptedPrivateKeyInfo {
 369
 370                         private string _algorithm;
 371                         private byte[] _salt;
 372                         private int _iterations;
 373                         private byte[] _data;
 374
 375                         public EncryptedPrivateKeyInfo () {}
 376
 377                         public EncryptedPrivateKeyInfo (byte[] data) : this ()
 378                         {
 379                                 Decode (data);
 380                         }
 381
 382                         // properties
 383
 384                         public string Algorithm {
 385                                 get { return _algorithm; }
 386                                 set { _algorithm = value; }
 387                         }
 388
 389                         public byte[] EncryptedData {
 390                                 get { return (_data == null) ? null : (byte[]) _data.Clone (); }
 391                                 set { _data = (value == null) ? null : (byte[]) value.Clone (); }
 392                         }
 393
 394                         public byte[] Salt {
 395                                 get {
 396                                         if (_salt == null) {
 397                                                 RandomNumberGenerator rng = RandomNumberGenerator.Create ();
 398                                                 _salt = new byte [8];
 399                                                 rng.GetBytes (_salt);
 400                                         }
 401                                         return (byte[]) _salt.Clone ();
 402                                 }
 403                                 set { _salt = (byte[]) value.Clone (); }
 404                         }
 405
 406                         public int IterationCount {
 407                                 get { return _iterations; }
 408                                 set {
 409                                         if (value < 0)
 410                                                 throw new ArgumentOutOfRangeException ("IterationCount", "Negative");
 411                                         _iterations = value;
 412                                 }
 413                         }
 414
 415                         // methods
 416
 417                         private void Decode (byte[] data)
 418                         {
 419                                 ASN1 encryptedPrivateKeyInfo = new ASN1 (data);
 420                                 if (encryptedPrivateKeyInfo.Tag != 0x30)
 421                                         throw new CryptographicException ("invalid EncryptedPrivateKeyInfo");
 422
 423                                 ASN1 encryptionAlgorithm = encryptedPrivateKeyInfo [0];
 424                                 if (encryptionAlgorithm.Tag != 0x30)
 425                                         throw new CryptographicException ("invalid encryptionAlgorithm");
 426                                 ASN1 algorithm = encryptionAlgorithm [0];
 427                                 if (algorithm.Tag != 0x06)
 428                                         throw new CryptographicException ("invalid algorithm");
 429                                 _algorithm = ASN1Convert.ToOid (algorithm);
 430                                 // parameters ANY DEFINED BY algorithm OPTIONAL
 431                                 if (encryptionAlgorithm.Count > 1) {
 432                                         ASN1 parameters = encryptionAlgorithm [1];
 433                                         if (parameters.Tag != 0x30)
 434                                                 throw new CryptographicException ("invalid parameters");
 435
 436                                         ASN1 salt = parameters [0];
 437                                         if (salt.Tag != 0x04)
 438                                                 throw new CryptographicException ("invalid salt");
 439                                         _salt = salt.Value;
 440
 441                                         ASN1 iterationCount = parameters [1];
 442                                         if (iterationCount.Tag != 0x02)
 443                                                 throw new CryptographicException ("invalid iterationCount");
 444                                         _iterations = ASN1Convert.ToInt32 (iterationCount);
 445                                 }
 446
 447                                 ASN1 encryptedData = encryptedPrivateKeyInfo [1];
 448                                 if (encryptedData.Tag != 0x04)
 449                                         throw new CryptographicException ("invalid EncryptedData");
 450                                 _data = encryptedData.Value;
 451                         }
 452
 453                         // Note: PKCS#8 doesn't define how to generate the key required for encryption
 454                         // so you're on your own. Just don't try to copy the big guys too much ;)
 455                         // Netscape:    http://www.cs.auckland.ac.nz/~pgut001/pubs/netscape.txt
 456                         // Microsoft:   http://www.cs.auckland.ac.nz/~pgut001/pubs/breakms.txt
 457                         public byte[] GetBytes ()
 458                         {
 459                                 if (_algorithm == null)
 460                                         throw new CryptographicException ("No algorithm OID specified");
 461
 462                                 ASN1 encryptionAlgorithm = new ASN1 (0x30);
 463                                 encryptionAlgorithm.Add (ASN1Convert.FromOid (_algorithm));
 464
 465                                 // parameters ANY DEFINED BY algorithm OPTIONAL
 466                                 if ((_iterations > 0) || (_salt != null)) {
 467                                         ASN1 salt = new ASN1 (0x04, _salt);
 468                                         ASN1 iterations = ASN1Convert.FromInt32 (_iterations);
 469
 470                                         ASN1 parameters = new ASN1 (0x30);
 471                                         parameters.Add (salt);
 472                                         parameters.Add (iterations);
 473                                         encryptionAlgorithm.Add (parameters);
 474                                 }
 475
 476                                 // encapsulates EncryptedData into an OCTET STRING
 477                                 ASN1 encryptedData = new ASN1 (0x04, _data);
 478
 479                                 ASN1 encryptedPrivateKeyInfo = new ASN1 (0x30);
 480                                 encryptedPrivateKeyInfo.Add (encryptionAlgorithm);
 481                                 encryptedPrivateKeyInfo.Add (encryptedData);
 482
 483                                 return encryptedPrivateKeyInfo.GetBytes ();
 484                         }
 485                 }
 486         }
 487 }