/// <summary>
/// Reads XML conforming to https://www.w3.org/TR/2001/PR-xmldsig-core-20010820/#sec-SignatureMethod
/// </summary>
/// <param name="reader">a <see cref="XmlReader"/>positioned on a <SignatureMethod> element.</param>
/// <exception cref="ArgumentNullException">if <paramref name="reader"/> is null.</exception>
/// <exception cref="XmlReadException">if there is a problem reading the XML.</exception>
/// <returns>A string with the signature method.</returns>
public virtual string ReadSignatureMethod(XmlReader reader)
{
XmlUtil.CheckReaderOnEntry(reader, XmlSignatureConstants.Elements.SignatureMethod, XmlSignatureConstants.Namespace);
try
{
bool isEmptyElement = reader.IsEmptyElement;
var signatureMethod = reader.GetAttribute(XmlSignatureConstants.Attributes.Algorithm, null);
if (signatureMethod == null)
{
throw XmlUtil.OnRequiredAttributeMissing(XmlSignatureConstants.Elements.SignatureMethod, XmlSignatureConstants.Attributes.Algorithm);
}
reader.Read();
reader.MoveToContent();
if (!isEmptyElement)
{
reader.MoveToContent();
reader.ReadEndElement();
}
return(signatureMethod);
}
catch (Exception ex)
{
if (ex is XmlReadException)
{
throw;
}
throw XmlUtil.LogReadException(LogMessages.IDX30016, ex, XmlSignatureConstants.Elements.Transform);
}
}
/// <summary>
/// Reads XML conforming to https://www.w3.org/TR/2001/PR-xmldsig-core-20010820/#sec-Reference
/// </summary>
/// <param name="reader">a <see cref="XmlReader"/>positioned on a <Reference> element.</param>
/// <exception cref="ArgumentNullException">if <paramref name="reader"/> is null.</exception>
/// <exception cref="XmlReadException">if there is a problem reading the XML.</exception>
/// <returns><see cref="Reference"/></returns>
public virtual Reference ReadReference(XmlReader reader)
{
XmlUtil.CheckReaderOnEntry(reader, XmlSignatureConstants.Elements.Reference, XmlSignatureConstants.Namespace);
try
{
var reference = new Reference
{
Prefix = reader.Prefix,
Id = reader.GetAttribute(XmlSignatureConstants.Attributes.Id, null),
Type = reader.GetAttribute(XmlSignatureConstants.Attributes.Type, null),
Uri = reader.GetAttribute(XmlSignatureConstants.Attributes.URI, null)
};
reader.Read();
ReadTransforms(reader, reference);
// <DigestMethod> - required
XmlUtil.CheckReaderOnEntry(reader, XmlSignatureConstants.Elements.DigestMethod, XmlSignatureConstants.Namespace);
bool isEmptyElement = reader.IsEmptyElement;
var digestMethod = reader.GetAttribute(XmlSignatureConstants.Attributes.Algorithm, null);
if (string.IsNullOrEmpty(digestMethod))
{
throw XmlUtil.OnRequiredAttributeMissing(XmlSignatureConstants.Elements.DigestMethod, XmlSignatureConstants.Attributes.Algorithm);
}
reference.DigestMethod = digestMethod;
reader.Read();
reader.MoveToContent();
if (!isEmptyElement)
{
reader.ReadEndElement();
}
// <DigestValue>
XmlUtil.CheckReaderOnEntry(reader, XmlSignatureConstants.Elements.DigestValue, XmlSignatureConstants.Namespace);
var digestValue = reader.ReadElementContentAsString().Trim();
if (string.IsNullOrEmpty(digestValue))
{
throw XmlUtil.LogReadException(LogMessages.IDX30206, reference.Uri ?? reference.Id);
}
reference.DigestValue = digestValue;
// </Reference>
reader.MoveToContent();
reader.ReadEndElement();
return(reference);
}
catch (Exception ex)
{
if (ex is XmlReadException)
{
throw;
}
throw XmlUtil.LogReadException(LogMessages.IDX30016, ex, XmlSignatureConstants.Elements.Reference);
}
}