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

   1 //
   2 // DataObject.cs - DataObject implementation for XML Signature
   3 // http://www.w3.org/2000/09/xmldsig#Object
   4 //
   5 // Author:
   6 //      Sebastien Pouliot (spouliot@motus.com)
   7 //      Atsushi Enomoto (atsushi@ximian.com)
   8 //
   9 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
  10 // (C) 2004 Novell Inc.
  11 //
  12
  13 using System.Xml;
  14
  15 namespace System.Security.Cryptography.Xml {
  16
  17         // XmlElement part of the signature
  18         // Note: Looks like KeyInfoNode (but the later is XmlElement inside KeyInfo)
  19         // required for "enveloping signatures"
  20         public class DataObject {
  21
  22                 private string id;
  23                 private string mimeType;
  24                 private string encoding;
  25                 private XmlElement element;
  26                 private bool propertyModified;
  27
  28                 public DataObject ()
  29                 {
  30                         Build (null, null, null, null);
  31                 }
  32
  33                 public DataObject (string id, string mimeType, string encoding, XmlElement data)
  34                 {
  35                         if (data == null)
  36                                 throw new ArgumentNullException ("data");
  37
  38                         Build (id, mimeType, encoding, data);
  39                 }
  40
  41                 // this one accept a null "data" parameter
  42                 private void Build (string id, string mimeType, string encoding, XmlElement data)
  43                 {
  44                         XmlDocument document = new XmlDocument ();
  45                         XmlElement xel = document.CreateElement (XmlSignature.ElementNames.Object, XmlSignature.NamespaceURI);
  46                         if (id != null) {
  47                                 this.id = id;
  48                                 xel.SetAttribute (XmlSignature.AttributeNames.Id, id);
  49                         }
  50                         if (mimeType != null) {
  51                                 this.mimeType = mimeType;
  52                                 xel.SetAttribute (XmlSignature.AttributeNames.MimeType, mimeType);
  53                         }
  54                         if (encoding != null) {
  55                                 this.encoding = encoding;
  56                                 xel.SetAttribute (XmlSignature.AttributeNames.Encoding, encoding);
  57                         }
  58                         if (data != null) {
  59                                 XmlNode newNode = document.ImportNode (data, true);
  60                                 xel.AppendChild (newNode);
  61                         }
  62                         document.AppendChild (xel); // FIXME: it should not be appended
  63
  64                         element = document.DocumentElement;
  65                 }
  66
  67                 // why is data a XmlNodeList instead of a XmlElement ?
  68                 public XmlNodeList Data {
  69                         get {
  70                                 return element.ChildNodes;
  71                         }
  72                         set {
  73                                 if (value == null)
  74                                         throw new ArgumentNullException ("value");
  75                                 XmlDocument doc = new XmlDocument ();
  76                                 XmlElement el = (XmlElement) doc.ImportNode (element, true);
  77                                 doc.AppendChild (el); // FIXME: it should not be appended
  78                                 el.RemoveAll ();
  79                                 foreach (XmlNode n in value)
  80                                         el.AppendChild (doc.ImportNode (n, true));
  81                                 element = el;
  82                                 propertyModified = true;
  83                         }
  84                 }
  85
  86                 // default to null - no encoding
  87                 public string Encoding {
  88                         get { return GetField (XmlSignature.AttributeNames.Encoding); }
  89                         set { SetField (XmlSignature.AttributeNames.Encoding, value); }
  90                 }
  91
  92                 // default to null
  93                 public string Id {
  94                         get { return GetField (XmlSignature.AttributeNames.Id); }
  95                         set { SetField (XmlSignature.AttributeNames.Id, value); }
  96                 }
  97
  98                 // default to null
  99                 public string MimeType {
 100                         get { return GetField (XmlSignature.AttributeNames.MimeType); }
 101                         set { SetField (XmlSignature.AttributeNames.MimeType, value); }
 102                 }
 103
 104                 private string GetField (string attribute)
 105                 {
 106                         XmlNode attr = element.Attributes [attribute];
 107                         return attr != null ? attr.Value : null;
 108                 }
 109
 110                 private void SetField (string attribute, string value)
 111                 {
 112                         // MS-BUGS: it never cleans attribute value up.
 113                         if (value == null)
 114                                 return;
 115
 116                         if (propertyModified)
 117                                 element.SetAttribute (attribute, value);
 118                         else {
 119                                 XmlDocument document = new XmlDocument ();
 120                                 XmlElement el = document.ImportNode (element, true) as XmlElement;
 121                                 el.Attributes.RemoveAll ();
 122                                 document.AppendChild (el); // FIXME: it should not be appended
 123                                 el.SetAttribute (attribute, value);
 124                                 element = el;
 125                                 propertyModified = true;
 126                         }
 127                 }
 128
 129                 public XmlElement GetXml ()
 130                 {
 131                         if (propertyModified) {
 132                                 // It looks MS.NET returns element which comes from new XmlDocument every time
 133                                 XmlElement oldElement = element;
 134                                 XmlDocument doc = new XmlDocument ();
 135                                 element = doc.CreateElement (XmlSignature.ElementNames.Object, XmlSignature.NamespaceURI);
 136                                 doc.AppendChild (element); // FIXME: it should not be appended
 137                                 foreach (XmlAttribute attribute in oldElement.Attributes) {
 138                                         switch (attribute.Name) {
 139                                         case XmlSignature.AttributeNames.Id:
 140                                         case XmlSignature.AttributeNames.Encoding:
 141                                         case XmlSignature.AttributeNames.MimeType:
 142                                                 element.SetAttribute (attribute.Name, attribute.Value);
 143                                                 break;
 144                                         }
 145                                 }
 146                                 foreach (XmlNode n in oldElement.ChildNodes)
 147                                         element.AppendChild (doc.ImportNode (n, true));
 148                         }
 149                         return element;
 150                 }
 151
 152                 public void LoadXml (XmlElement value)
 153                 {
 154                         if (value == null)
 155                                 throw new ArgumentNullException ("value");
 156                         element = value;
 157                         propertyModified = false;
 158                 }
 159         }
 160 }