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

   1 //
   2 // System.Security.Cryptography.RSA.cs
   3 //
   4 // Authors:
   5 //   Dan Lewis (dihlewis@yahoo.co.uk)
   6 //   Sebastien Pouliot (spouliot@motus.com)
   7 //
   8 // (C) 2002
   9 // Portions (C) 2002 Motus Technologies Inc. (http://www.motus.com)
  10 //
  11
  12 using System;
  13 using System.Text;
  14
  15 namespace System.Security.Cryptography
  16 {
  17         internal class RSAHandler : MiniParser.IHandler {
  18
  19                 private RSAParameters rsa;
  20                 private bool unknown;
  21                 private byte[] temp;
  22
  23                 public RSAHandler ()
  24                 {
  25                         rsa = new RSAParameters();
  26                 }
  27
  28                 public RSAParameters GetParams () {
  29                         return rsa;
  30                 }
  31
  32                 public void OnStartParsing (MiniParser parser) {}
  33
  34                 public void OnStartElement (string name, MiniParser.IAttrList attrs) {}
  35
  36                 public void OnEndElement (string name) {
  37                         switch (name) {
  38                                 case "P":
  39                                         rsa.P = temp;
  40                                         break;
  41                                 case "Q":
  42                                         rsa.Q = temp;
  43                                         break;
  44                                 case "D":
  45                                         rsa.D = temp;
  46                                         break;
  47                                 case "DP":
  48                                         rsa.DP = temp;
  49                                         break;
  50                                 case "DQ":
  51                                         rsa.DQ = temp;
  52                                         break;
  53                                 case "Exponent":
  54                                         rsa.Exponent = temp;
  55                                         break;
  56                                 case "InverseQ":
  57                                         rsa.InverseQ = temp;
  58                                         break;
  59                                 case "Modulus":
  60                                         rsa.Modulus = temp;
  61                                         break;
  62                                 default:
  63                                         // unknown tag in parameters
  64                                         break;
  65                         }
  66                 }
  67
  68                 public void OnChars (string ch)
  69                 {
  70                         temp = Convert.FromBase64String (ch);
  71                 }
  72
  73                 public void OnEndParsing (MiniParser parser) {}
  74         }
  75
  76         public abstract class RSA : AsymmetricAlgorithm
  77         {
  78                 public static new RSA Create ()
  79                 {
  80                         return Create ("System.Security.Cryptography.RSA");
  81                 }
  82
  83                 public static new RSA Create (string algName)
  84                 {
  85                         return (RSA) CryptoConfig.CreateFromName (algName);
  86                 }
  87
  88                 public RSA () { }
  89
  90                 public abstract byte[] EncryptValue (byte[] rgb);
  91                 public abstract byte[] DecryptValue (byte[] rgb);
  92
  93                 public abstract RSAParameters ExportParameters (bool include);
  94                 public abstract void ImportParameters (RSAParameters parameters);
  95
  96                 protected void ZeroizePrivateKey (RSAParameters parameters)
  97                 {
  98                         if (parameters.P != null)
  99                                 Array.Clear(parameters.P, 0, parameters.P.Length);
 100                         if (parameters.Q != null)
 101                                 Array.Clear(parameters.Q, 0, parameters.Q.Length);
 102                         if (parameters.DP != null)
 103                                 Array.Clear(parameters.DP, 0, parameters.DP.Length);
 104                         if (parameters.DQ != null)
 105                                 Array.Clear(parameters.DQ, 0, parameters.DQ.Length);
 106                         if (parameters.InverseQ != null)
 107                                 Array.Clear(parameters.InverseQ, 0, parameters.InverseQ.Length);
 108                         if (parameters.D != null)
 109                                 Array.Clear(parameters.D, 0, parameters.D.Length);
 110                 }
 111
 112                 public override void FromXmlString (string xmlString)
 113                 {
 114                         if (xmlString == null)
 115                                 throw new ArgumentNullException ();
 116
 117                         RSAParameters rsaParams = new RSAParameters ();
 118                         try {
 119                                 MiniParser parser = new MiniParser ();
 120                                 AsymmetricParameters reader = new AsymmetricParameters (xmlString);
 121                                 RSAHandler handler = new RSAHandler ();
 122                                 parser.Parse(reader, handler);
 123                                 ImportParameters (handler.GetParams ());
 124                         }
 125                         catch {
 126                                 ZeroizePrivateKey (rsaParams);
 127                                 throw new CryptographicException ();
 128                         }
 129                         finally {
 130                                 ZeroizePrivateKey (rsaParams);
 131                         }
 132                 }
 133
 134                 public override string ToXmlString (bool includePrivateParameters)
 135                 {
 136                         StringBuilder sb = new StringBuilder ();
 137                         RSAParameters rsaParams = ExportParameters (includePrivateParameters);
 138                         try {
 139                                 sb.Append ("<RSAKeyValue>");
 140
 141                                 sb.Append ("<Modulus>");
 142                                 sb.Append (Convert.ToBase64String (rsaParams.Modulus));
 143                                 sb.Append ("</Modulus>");
 144
 145                                 sb.Append ("<Exponent>");
 146                                 sb.Append (Convert.ToBase64String (rsaParams.Exponent));
 147                                 sb.Append ("</Exponent>");
 148
 149                                 if (includePrivateParameters)
 150                                 {
 151                                         sb.Append ("<P>");
 152                                         sb.Append (Convert.ToBase64String (rsaParams.P));
 153                                         sb.Append ("</P>");
 154
 155                                         sb.Append ("<Q>");
 156                                         sb.Append (Convert.ToBase64String (rsaParams.Q));
 157                                         sb.Append ("</Q>");
 158
 159                                         sb.Append ("<DP>");
 160                                         sb.Append (Convert.ToBase64String (rsaParams.DP));
 161                                         sb.Append ("</DP>");
 162
 163                                         sb.Append ("<DQ>");
 164                                         sb.Append (Convert.ToBase64String (rsaParams.DQ));
 165                                         sb.Append ("</DQ>");
 166
 167                                         sb.Append ("<InverseQ>");
 168                                         sb.Append (Convert.ToBase64String (rsaParams.InverseQ));
 169                                         sb.Append ("</InverseQ>");
 170
 171                                         sb.Append ("<D>");
 172                                         sb.Append (Convert.ToBase64String (rsaParams.D));
 173                                         sb.Append ("</D>");
 174                                 }
 175
 176                                 sb.Append ("</RSAKeyValue>");
 177                         }
 178                         catch {
 179                                 ZeroizePrivateKey (rsaParams);
 180                                 throw;
 181                         }
 182
 183                         return sb.ToString ();
 184                 }
 185         }
 186 }