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 #if NET_1_2
  11
  12 using System.Xml;
  13
  14 namespace System.Security.Cryptography.Xml {
  15         public class EncryptionMethod {
  16
  17                 #region Fields
  18
  19                 string algorithm;
  20                 int keySize;
  21
  22                 #endregion // Fields
  23
  24                 #region Constructors
  25
  26                 public EncryptionMethod ()
  27                 {
  28                         KeyAlgorithm = null;
  29                 }
  30
  31                 public EncryptionMethod (string strAlgorithm)
  32                 {
  33                         KeyAlgorithm = strAlgorithm;
  34                 }
  35
  36                 #endregion // Constructors
  37
  38                 #region Properties
  39
  40                 public string KeyAlgorithm {
  41                         get { return algorithm; }
  42                         set { algorithm = value; }
  43                 }
  44
  45                 public int KeySize {
  46                         get { return keySize; }
  47                         set {
  48                                 if (value <= 0)
  49                                         throw new ArgumentOutOfRangeException ("The key size should be a non negative integer.");
  50                                 keySize = value;
  51                         }
  52                 }
  53
  54                 #endregion // Properties
  55
  56                 #region Methods
  57
  58                 public XmlElement GetXml ()
  59                 {
  60                         return GetXml (new XmlDocument ());
  61                 }
  62
  63                 internal XmlElement GetXml (XmlDocument document)
  64                 {
  65                         XmlElement xel = document.CreateElement (XmlEncryption.ElementNames.EncryptionMethod, XmlEncryption.NamespaceURI);
  66
  67                         if (KeySize != 0) {
  68                                 XmlElement xks = document.CreateElement (XmlEncryption.ElementNames.KeySize, XmlEncryption.NamespaceURI);
  69                                 xks.InnerText = String.Format ("{0}", keySize);
  70                                 xel.AppendChild (xks);
  71                         }
  72
  73                         if (KeyAlgorithm != null)
  74                                 xel.SetAttribute (XmlEncryption.AttributeNames.Algorithm, KeyAlgorithm);
  75                         return xel;
  76                 }
  77
  78                 public void LoadXml (XmlElement value)
  79                 {
  80                         if (value == null)
  81                                 throw new ArgumentNullException ("value");
  82                         if ((value.LocalName != XmlEncryption.ElementNames.EncryptionMethod) || (value.NamespaceURI != XmlEncryption.NamespaceURI))
  83                                 throw new CryptographicException ("Malformed EncryptionMethod element.");
  84                         else {
  85                                 KeyAlgorithm = null;
  86                                 foreach (XmlNode n in value.ChildNodes) {
  87                                         if (n is XmlWhitespace)
  88                                                 continue;
  89                                         switch (n.LocalName) {
  90                                         case XmlEncryption.ElementNames.KeySize:
  91                                                 KeySize = Int32.Parse (n.InnerText);
  92                                                 break;
  93                                         }
  94                                 }
  95                                 if (value.HasAttribute (XmlEncryption.AttributeNames.Algorithm))
  96                                         KeyAlgorithm = value.Attributes [XmlEncryption.AttributeNames.Algorithm].Value;
  97                         }
  98                 }
  99
 100                 #endregion // Methods
 101         }
 102 }
 103
 104 #endif