mcs/class/System.Security/System.Security.Cryptography/ProtectedData.cs

   1 //
   2 // ProtectedData.cs: Protect (encrypt) data without (user involved) key management
   3 //
   4 // Author:\r
   5 //      Sebastien Pouliot  <sebastien@ximian.com>\r
   6 //
   7 // (C) 2003 Motus Technologies Inc. (http://www.motus.com)\r
   8 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)\r
   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 #if NET_2_0\r
  31 \r
  32 using System.Runtime.InteropServices;\r
  33 using System.Security.Permissions;
  34
  35 using Mono.Security.Cryptography;
  36
  37 namespace System.Security.Cryptography {
  38
  39         // References:
  40         // a.   Windows Data Protection
  41         //      http://msdn.microsoft.com/library/en-us/dnsecure/html/windataprotection-dpapi.asp?frame=true
  42
  43         public sealed class ProtectedData {
  44
  45                 private ProtectedData ()
  46                 {
  47                 }
  48
  49 // FIXME        [DataProtectionPermission (SecurityAction.Demand, ProtectData = true)]\r
  50                 public static byte[] Protect (byte[] userData, byte[] optionalEntropy, DataProtectionScope scope)
  51                 {
  52                         if (userData == null)
  53                                 throw new ArgumentNullException ("userData");
  54
  55                         // on Windows this is supported only under 2000 and later OS\r
  56                         Check (scope);\r
  57 \r
  58                         switch (impl) {\r
  59                         case DataProtectionImplementation.ManagedProtection:\r
  60                                 try {\r
  61                                         return ManagedProtection.Protect (userData, optionalEntropy, scope);\r
  62                                 }\r
  63                                 catch (Exception e) {\r
  64                                         string msg = Locale.GetText ("Data protection failed.");\r
  65                                         throw new CryptographicException (msg, e);\r
  66                                 }\r
  67                         case DataProtectionImplementation.Win32CryptoProtect:\r
  68                                 try {\r
  69                                         return NativeDapiProtection.Protect (userData, optionalEntropy, scope);\r
  70                                 }\r
  71                                 catch (Exception e) {\r
  72                                         string msg = Locale.GetText ("Data protection failed.");\r
  73                                         throw new CryptographicException (msg, e);\r
  74                                 }\r
  75                         default:\r
  76                                 throw new PlatformNotSupportedException ();\r
  77                         }\r
  78                 }\r
  79 \r
  80 // FIXME        [DataProtectionPermission (SecurityAction.Demand, UnprotectData = true)]\r
  81                 public static byte[] Unprotect (byte[] encryptedData, byte[] optionalEntropy, DataProtectionScope scope)
  82                 {
  83                         if (encryptedData == null)
  84                                 throw new ArgumentNullException ("encryptedData");
  85
  86                         // on Windows this is supported only under 2000 and later OS\r
  87                         Check (scope);\r
  88 \r
  89                         switch (impl) {\r
  90                         case DataProtectionImplementation.ManagedProtection:\r
  91                                 try {\r
  92                                         return ManagedProtection.Unprotect (encryptedData, optionalEntropy, scope);\r
  93                                 }\r
  94                                 catch (Exception e) {\r
  95                                         string msg = Locale.GetText ("Data unprotection failed.");\r
  96                                         throw new CryptographicException (msg, e);\r
  97                                 }\r
  98                         case DataProtectionImplementation.Win32CryptoProtect:\r
  99                                 try {\r
 100                                         return NativeDapiProtection.Unprotect (encryptedData, optionalEntropy, scope);\r
 101                                 }\r
 102                                 catch (Exception e) {\r
 103                                         string msg = Locale.GetText ("Data unprotection failed.");\r
 104                                         throw new CryptographicException (msg, e);\r
 105                                 }\r
 106                         default:\r
 107                                 throw new PlatformNotSupportedException ();\r
 108                         }\r
 109                 }
 110
 111                 // private stuff\r
 112 \r
 113                 enum DataProtectionImplementation {\r
 114                         Unknown,\r
 115                         Win32CryptoProtect,\r
 116                         ManagedProtection,\r
 117                         Unsupported = Int32.MinValue\r
 118                 }\r
 119 \r
 120                 private static DataProtectionImplementation impl;\r
 121 \r
 122                 private static void Detect ()\r
 123                 {\r
 124                         OperatingSystem os = Environment.OSVersion;\r
 125                         switch (os.Platform) {\r
 126                         case PlatformID.Win32NT:\r
 127                                 Version v = os.Version;\r
 128                                 if (v.Major < 5) {\r
 129                                         impl = DataProtectionImplementation.Unsupported;\r
 130                                 } else {\r
 131                                         // Windows 2000 (5.0) and later\r
 132                                         impl = DataProtectionImplementation.Win32CryptoProtect;\r
 133                                 }\r
 134                                 break;\r
 135                         case PlatformID.Unix:\r
 136                                 impl = DataProtectionImplementation.ManagedProtection;\r
 137                                 break;\r
 138                         default:\r
 139                                 impl = DataProtectionImplementation.Unsupported;\r
 140                                 break;\r
 141                         }\r
 142                 }\r
 143 \r
 144                 private static void Check (DataProtectionScope scope)\r
 145                 {\r
 146                         if ((scope < DataProtectionScope.CurrentUser) || (scope > DataProtectionScope.LocalMachine)) {\r
 147                                 string msg = Locale.GetText ("Invalid enum value '{0}' for '{1}'.", \r
 148                                         scope, "DataProtectionScope");\r
 149                                 throw new ArgumentException (msg, "scope");\r
 150                         }\r
 151 \r
 152                         switch (impl) {\r
 153                         case DataProtectionImplementation.Unknown:\r
 154                                 Detect ();\r
 155                                 break;\r
 156                         case DataProtectionImplementation.Unsupported:\r
 157                                 throw new PlatformNotSupportedException ();\r
 158                         }\r
 159                 }\r
 160         }
 161 }
 162
 163 #endif