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

//
// XmlDsigXPathTransform.cs - 
//	XmlDsigXPathTransform implementation for XML Signature
// http://www.w3.org/TR/1999/REC-xpath-19991116 
//
// Author:
//	Sebastien Pouliot ([email protected])
//
// (C) 2002 Motus Technologies Inc. (http://www.motus.com)
//

using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Xml;

namespace System.Security.Cryptography.Xml {

// www.w3.org/TR/xmldsig-core/
// see Section 6.6.3 of the XMLDSIG specification
public class XmlDsigXPathTransform : Transform {

	private XmlNodeList xnl;
	private XmlNodeList xpathNodes;

	public XmlDsigXPathTransform () 
	{
	}

	public override Type[] InputTypes {
		get {
			if (input == null) {
				lock (this) {
					// this way the result is cached if called multiple time
					input = new Type [3];
					input[0] = typeof (System.IO.Stream);
					input[1] = typeof (System.Xml.XmlDocument);
					input[2] = typeof (System.Xml.XmlNodeList);
				}
			}
			return input;
		}
	}

	public override Type[] OutputTypes {
		get {
			if (output == null) {
				lock (this) {
					// this way the result is cached if called multiple time
					output = new Type [1];
					output[0] = typeof (System.IO.Stream);
				}
			}
			return output;
		}
	}

	protected override XmlNodeList GetInnerXml () 
	{
		return xnl;
	}

	public override object GetOutput () 
	{
		return xpathNodes;
	}

	public override object GetOutput (Type type) 
	{
		if (type != typeof (XmlNodeList))
			throw new ArgumentException ("type");
		return GetOutput ();
	}

	public override void LoadInnerXml (XmlNodeList nodeList) 
	{
		if (nodeList == null)
			throw new CryptographicException ("nodeList");
		xnl = nodeList;
	}

	public override void LoadInput (object obj) 
	{
		XmlNode xn = null;
		// possible input: Stream, XmlDocument, and XmlNodeList
		if (obj is Stream) {
			XmlDocument doc = new XmlDocument ();
			doc.Load (obj as Stream);
		}
		else if (obj is XmlDocument) {
		}
		else if (obj is XmlNodeList) {
			xnl = (XmlNodeList) obj;
		}

		if (xn != null) {
			string xpath = xn.InnerXml;
			// only possible output: XmlNodeList
			xpathNodes = xnl[0].SelectNodes (xpath);
		}
		else
			xpathNodes = null;
	}
}

}