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

   1 //
   2 // XmlDsigXPathTransform.cs -
   3 //      XmlDsigXPathTransform implementation for XML Signature
   4 // http://www.w3.org/TR/1999/REC-xpath-19991116
   5 //
   6 // Author:
   7 //      Sebastien Pouliot <sebastien@ximian.com>
   8 //
   9 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
  10 // (C) 2004 Novell (http://www.novell.com)
  11 //
  12
  13 using System.IO;
  14 using System.Text;
  15 using System.Xml;
  16
  17 namespace System.Security.Cryptography.Xml {
  18
  19         // www.w3.org/TR/xmldsig-core/
  20         // see Section 6.6.3 of the XMLDSIG specification
  21         [MonoTODO]
  22         public class XmlDsigXPathTransform : Transform {
  23
  24                 private Type[] input;
  25                 private Type[] output;
  26                 private XmlNodeList xpath;
  27                 private XmlDocument doc;
  28
  29                 public XmlDsigXPathTransform ()
  30                 {
  31                         Algorithm = "http://www.w3.org/TR/1999/REC-xpath-19991116";
  32                 }
  33
  34                 public override Type[] InputTypes {
  35                         get {
  36                                 if (input == null) {
  37                                         lock (this) {
  38                                                 // this way the result is cached if called multiple time
  39                                                 input = new Type [3];
  40                                                 input[0] = typeof (System.IO.Stream);
  41                                                 input[1] = typeof (System.Xml.XmlDocument);
  42                                                 input[2] = typeof (System.Xml.XmlNodeList);
  43                                         }
  44                                 }
  45                                 return input;
  46                         }
  47                 }
  48
  49                 public override Type[] OutputTypes {
  50                         get {
  51                                 if (output == null) {
  52                                         lock (this) {
  53                                                 // this way the result is cached if called multiple time
  54                                                 output = new Type [1];
  55                                                 output[0] = typeof (System.Xml.XmlNodeList);
  56                                         }
  57                                 }
  58                                 return output;
  59                         }
  60                 }
  61
  62                 protected override XmlNodeList GetInnerXml ()
  63                 {
  64                         if (xpath == null) {
  65                                 // default value
  66                                 XmlDocument doc = new XmlDocument ();
  67                                 doc.LoadXml ("<XPath xmlns=\"" + XmlSignature.NamespaceURI + "\"></XPath>");
  68                                 xpath = doc.ChildNodes;
  69                         }
  70                         return xpath;
  71                 }
  72
  73                 public override object GetOutput ()
  74                 {
  75                         // note: this will throw a NullReferenceException if
  76                         // doc is null - just like MS implementation does
  77                         if ((xpath == null) || (xpath.Count < 1)) {
  78                                 // can't create an XmlNodeList
  79                                 XmlDocument xd = new XmlDocument ();
  80                                 return xd.ChildNodes;
  81                         }
  82                         return doc.ChildNodes;
  83 //* I know it doesn't make a lot of sense - but this is what the MS framework
  84 //* returns - I must miss something really bad
  85 //*                     return doc.DocumentElement.SelectNodes (xpath [0].InnerXml);
  86                 }
  87
  88                 public override object GetOutput (Type type)
  89                 {
  90                         if (type != typeof (XmlNodeList))
  91                                 throw new ArgumentException ("type");
  92                         return GetOutput ();
  93                 }
  94
  95                 public override void LoadInnerXml (XmlNodeList nodeList)
  96                 {
  97                         if (nodeList == null)
  98                                 throw new CryptographicException ("nodeList");
  99                         xpath = nodeList;
 100                 }
 101
 102                 public override void LoadInput (object obj)
 103                 {
 104                         // possible input: Stream, XmlDocument, and XmlNodeList
 105                         if (obj is Stream) {
 106                                 doc = new XmlDocument ();
 107                                 doc.Load (obj as Stream);
 108                         }
 109                         else if (obj is XmlDocument) {
 110                                 doc = (obj as XmlDocument);
 111                         }
 112                         else if (obj is XmlNodeList) {
 113                                 doc = new XmlDocument ();
 114                                 foreach (XmlNode xn in (obj as XmlNodeList))  {
 115                                         XmlNode importedNode = doc.ImportNode (xn, true);
 116                                         doc.AppendChild (importedNode);
 117                                 }
 118                         }
 119                 }
 120         }
 121 }