mcs/class/System.Security/System.Security.Cryptography.Xml/CipherData.cs

   1 //
   2 // CipherData.cs - CipherData implementation for XML Encryption
   3 // http://www.w3.org/2001/04/xmlenc#sec-CipherData
   4 //
   5 // Author:
   6 //      Tim Coleman (tim@timcoleman.com)
   7 //
   8 // Copyright (C) Tim Coleman, 2004
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31
  32 using System.Security.Cryptography;
  33 using System.IO;
  34 using System.Xml;
  35
  36 namespace System.Security.Cryptography.Xml {
  37         public sealed class CipherData {
  38
  39                 #region Fields
  40
  41                 byte[] cipherValue;
  42                 CipherReference cipherReference;
  43
  44                 #endregion // Fields
  45
  46                 #region Constructors
  47
  48                 public CipherData ()
  49                 {
  50                 }
  51
  52                 public CipherData (byte[] cipherValue)
  53                 {
  54                         CipherValue = cipherValue;
  55                 }
  56
  57                 public CipherData (CipherReference cipherReference)
  58                 {
  59                         CipherReference = cipherReference;
  60                 }
  61
  62                 #endregion // Constructors
  63
  64                 #region Properties
  65
  66                 public CipherReference CipherReference {
  67                         get { return cipherReference; }
  68                         set {
  69                                 if (CipherValue != null)
  70                                         throw new CryptographicException ("A Cipher Data element should have either a CipherValue or a CipherReference element.");
  71                                 cipherReference = value;
  72                         }
  73                 }
  74
  75                 public byte[] CipherValue {
  76                         get { return cipherValue; }
  77                         set {
  78                                 if (CipherReference != null)
  79                                         throw new CryptographicException ("A Cipher Data element should have either a CipherValue or a CipherReference element.");
  80                                 cipherValue = value;
  81                         }
  82                 }
  83
  84                 #endregion // Properties
  85
  86                 #region Methods
  87
  88                 public XmlElement GetXml ()
  89                 {
  90                         return GetXml (new XmlDocument ());
  91                 }
  92
  93                 internal XmlElement GetXml (XmlDocument document)
  94                 {
  95                         if (CipherReference == null && CipherValue == null)
  96                                 throw new CryptographicException ("A Cipher Data element should have either a CipherValue or a CipherReference element.");
  97
  98                         XmlElement xel = document.CreateElement (XmlEncryption.ElementNames.CipherData, EncryptedXml.XmlEncNamespaceUrl);
  99                         if (CipherReference != null)
 100                                 xel.AppendChild (document.ImportNode (cipherReference.GetXml (), true));
 101
 102                         if (CipherValue != null) {
 103                                 XmlElement xcv = document.CreateElement (XmlEncryption.ElementNames.CipherValue, EncryptedXml.XmlEncNamespaceUrl);
 104                                 StreamReader reader = new StreamReader (new CryptoStream (new MemoryStream (cipherValue), new ToBase64Transform (), CryptoStreamMode.Read));
 105                                 xcv.InnerText = reader.ReadToEnd ();
 106                                 reader.Close ();
 107                                 xel.AppendChild (xcv);
 108                         }
 109                         return xel;
 110                 }
 111
 112                 public void LoadXml (XmlElement value)
 113                 {
 114                         CipherReference = null;
 115                         CipherValue = null;
 116
 117                         if (value == null)
 118                                 throw new ArgumentNullException ("value");
 119
 120                         if ((value.LocalName != XmlEncryption.ElementNames.CipherData) || (value.NamespaceURI != EncryptedXml.XmlEncNamespaceUrl))
 121                                 throw new CryptographicException ("Malformed Cipher Data element.");
 122                         else {
 123                                 foreach (XmlNode n in value.ChildNodes) {
 124                                         if (n is XmlWhitespace)
 125                                                 continue;
 126
 127                                         switch (n.LocalName) {
 128                                         case XmlEncryption.ElementNames.CipherReference:
 129                                                 cipherReference = new CipherReference ();
 130                                                 cipherReference.LoadXml ((XmlElement) n);
 131                                                 break;
 132                                         case XmlEncryption.ElementNames.CipherValue:
 133                                                 CipherValue = Convert.FromBase64String (n.InnerText);
 134                                                 break;
 135                                         }
 136                                 }
 137
 138                                 if (CipherReference == null && CipherValue == null)
 139                                         throw new CryptographicException ("A Cipher Data element should have either a CipherValue or a CipherReference element.");
 140                         }
 141                 }
 142
 143                 #endregion // Methods
 144         }
 145 }
 146