/// <summary>
/// Returns the <see cref="XmlElement" /> object with the specified ID from the specified <see cref="XmlDocument" /> object.
/// </summary>
/// <param name="document">The <see cref="XmlDocument" /> object to retrieve the <see cref="XmlElement" /> object from.</param>
/// <param name="idValue">The ID of the <see cref="T:System.Xml.XmlElement" /> object to retrieve from the <see cref="XmlDocument" /> object.</param>
/// <returns>The <see cref="XmlElement" /> object with the specified ID from the specified <see cref="XmlDocument" /> object, or null if it could not be found.</returns>
public override XmlElement GetIdElement(
XmlDocument document,
string idValue)
{
if (document == null)
{
throw new ArgumentNullException(nameof(document));
}
if (idValue.IsNullOrWhiteSpace())
{
throw new ArgumentNullException(nameof(idValue));
}
var idElement = base.GetIdElement(document, idValue);
if (idElement != null)
{
return(idElement);
}
var nsManager = XmlConstants.GetXmlNamespaceManager(document);
foreach (var idName in _idAttributeNames)
{
if (document.SelectSingleNode(
string.Format(CultureInfo.InvariantCulture, xmlIdXPathFormat, idName, idValue),
nsManager) is XmlElement element)
{
return(element);
}
}
return(null);
}
public virtual void Decrypt(
XmlDocument document)
{
if (document == null)
{
throw new ArgumentNullException(nameof(document));
}
InitializeSymmetricKey();
foreach (XmlElement element in document.SelectNodes(XmlConstants.XPathEncryptedElements, XmlConstants.GetEncryptNamespaceManager(document)))
{
DecryptElement(element);
}
}
/// <summary>
/// Gets the references.
/// </summary>
/// <param name="signedXml">The signed XML.</param>
/// <param name="document">The document.</param>
/// <param name="xmlPath">The XML path.</param>
/// <param name="namespaceManager">The namespace manager.</param>
/// <param name="documentLocation">The document location.</param>
/// <returns>IEnumerable<Reference>.</returns>
IEnumerable <Reference> GetReferences(
SignedXml signedXml,
XmlDocument document,
string xmlPath,
XmlNamespaceManager namespaceManager,
Uri documentLocation)
{
XmlNodeList elements = null;
if (SignatureLocation == SignatureLocation.Enveloping)
{
// ignore the path - it doesn't make sense - always sign the document's root element and import it into /Signature/Object
xmlPath = _xPathRootElement;
}
if (xmlPath != null)
{
elements = document.SelectNodes(xmlPath, namespaceManager);
if (elements.Count == 1 && elements[0] is XmlDocument)
{
// the path points to the document node
elements = null;
}
}
if (elements == null)
{
// sign the whole document
var reference = new Reference();
if (SignatureLocation == SignatureLocation.Enveloped)
{
reference.AddTransform(new XmlDsigEnvelopedSignatureTransform());
}
if (SignatureLocation == SignatureLocation.Detached && documentLocation != null && !documentLocation.IsFile)
{
reference.Uri = documentLocation.ToString();
}
else
{
reference.Uri = "";
}
yield return(reference);
}
else
{
// build a set of all possible unique ID attribute names:
var nameIds = new HashSet <string> {
"id", "Id", "ID"
}; // these are always here
if (IdAttributeNames != null)
{
nameIds.UnionWith(IdAttributeNames); // add the custom ones
}
else
{
nameIds.Add(XmlConstants.Id); // add the XML standard one
}
var nsManager = XmlConstants.GetXmlNamespaceManager(document);
// a set of all unique id-s in the document will help us generate new unique xml:Id-s
var xmlIds = new HashSet <string>();
foreach (var name in nameIds)
{
xmlIds.UnionWith(
document.SelectNodes(
string.Format(CultureInfo.InvariantCulture, _xPathAllAttributes, name),
nsManager)
.OfType <XmlAttribute>()
.Select(a => a.Value)
.Distinct());
}
var id = 0;
foreach (var element in elements.OfType <XmlElement>())
{
string xmlId = null;
if (SignatureLocation == SignatureLocation.Enveloping)
{
// we need a new unique xml:Id for the Object element
xmlId = GetNewId(ref id, xmlIds);
// wrap the root element in a /Signature/Object element
signedXml.AddObject(
new DataObject
{
Data = elements, // contains the root element only
Id = xmlId, // add the xml:Id to the object, so that we can refer to it from the reference object
});
}
else
{
// find a unique ID - any one of the set should do
foreach (var name in nameIds)
{
if (element.SelectSingleNode("@" + name, nsManager) is XmlAttribute attribute && attribute.Value != null)
{
xmlId = attribute.Value;
break;
}
}
// if it doesn't have unique id, generate a new one and add it to the element, so that we can refer to it from the reference object
if (string.IsNullOrWhiteSpace(xmlId))
{
xmlId = GetNewId(ref id, xmlIds);
var attribute = document.CreateAttribute(XmlConstants.Prefix, XmlConstants.IdLocalName, XmlConstants.Namespace);
attribute.Value = xmlId;
element.Attributes.Append(attribute);
}
}
// create the reference object
var reference = new Reference("#" + xmlId)
{
DigestMethod = _digestMethod
};
switch (HashAlgorithmName)
{
case Algorithms.Hash.Sha256:
reference.AddTransform(new XmlDsigExcC14NTransform());
break;
#pragma warning disable 0612, 0618 // Type or member is obsolete - used for bacwards compatibility
case Algorithms.Hash.Sha1:
reference.AddTransform(new XmlDsigC14NTransform());
break;
#pragma warning restore 0612, 0618 // Type or member is obsolete - used for bacwards compatibility
}
if (SignatureLocation == SignatureLocation.Enveloped)
{
reference.AddTransform(new XmlDsigEnvelopedSignatureTransform());
}
yield return(reference);
}
}
}
