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

   1 //
   2 // EncryptionMethod.cs - EncryptionMethod implementation for XML Encryption
   3 // http://www.w3.org/2001/04/xmlenc#sec-EncryptionMethod
   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 #if NET_2_0
  32
  33 using System.Xml;
  34
  35 namespace System.Security.Cryptography.Xml {
  36         public class EncryptionMethod {
  37
  38                 #region Fields
  39
  40                 string algorithm;
  41                 int keySize;
  42
  43                 #endregion // Fields
  44
  45                 #region Constructors
  46
  47                 public EncryptionMethod ()
  48                 {
  49                         KeyAlgorithm = null;
  50                 }
  51
  52                 public EncryptionMethod (string strAlgorithm)
  53                 {
  54                         KeyAlgorithm = strAlgorithm;
  55                 }
  56
  57                 #endregion // Constructors
  58
  59                 #region Properties
  60
  61                 public string KeyAlgorithm {
  62                         get { return algorithm; }
  63                         set { algorithm = value; }
  64                 }
  65
  66                 public int KeySize {
  67                         get { return keySize; }
  68                         set {
  69                                 if (value <= 0)
  70                                         throw new ArgumentOutOfRangeException ("The key size should be a non negative integer.");
  71                                 keySize = value;
  72                         }
  73                 }
  74
  75                 #endregion // Properties
  76
  77                 #region Methods
  78
  79                 public XmlElement GetXml ()
  80                 {
  81                         return GetXml (new XmlDocument ());
  82                 }
  83
  84                 internal XmlElement GetXml (XmlDocument document)
  85                 {
  86                         XmlElement xel = document.CreateElement (XmlEncryption.ElementNames.EncryptionMethod, EncryptedXml.XmlEncNamespaceUrl);
  87
  88                         if (KeySize != 0) {
  89                                 XmlElement xks = document.CreateElement (XmlEncryption.ElementNames.KeySize, EncryptedXml.XmlEncNamespaceUrl);
  90                                 xks.InnerText = String.Format ("{0}", keySize);
  91                                 xel.AppendChild (xks);
  92                         }
  93
  94                         if (KeyAlgorithm != null)
  95                                 xel.SetAttribute (XmlEncryption.AttributeNames.Algorithm, KeyAlgorithm);
  96                         return xel;
  97                 }
  98
  99                 public void LoadXml (XmlElement value)
 100                 {
 101                         if (value == null)
 102                                 throw new ArgumentNullException ("value");
 103                         if ((value.LocalName != XmlEncryption.ElementNames.EncryptionMethod) || (value.NamespaceURI != EncryptedXml.XmlEncNamespaceUrl))
 104                                 throw new CryptographicException ("Malformed EncryptionMethod element.");
 105                         else {
 106                                 KeyAlgorithm = null;
 107                                 foreach (XmlNode n in value.ChildNodes) {
 108                                         if (n is XmlWhitespace)
 109                                                 continue;
 110                                         switch (n.LocalName) {
 111                                         case XmlEncryption.ElementNames.KeySize:
 112                                                 KeySize = Int32.Parse (n.InnerText);
 113                                                 break;
 114                                         }
 115                                 }
 116                                 if (value.HasAttribute (XmlEncryption.AttributeNames.Algorithm))
 117                                         KeyAlgorithm = value.Attributes [XmlEncryption.AttributeNames.Algorithm].Value;
 118                         }
 119                 }
 120
 121                 #endregion // Methods
 122         }
 123 }
 124
 125 #endif