public static (byte[] digest, Uri identifier) Digest(OpcPart part, HashAlgorithmName algorithmName)
{
var info = new HashAlgorithmInfo(algorithmName);
using (var hashAlgorithm = info.Create())
{
using (var partStream = part.Open())
{
var digest = hashAlgorithm.ComputeHash(partStream);
return(digest, info.XmlDSigIdentifier);
}
}
}
public XmlDocument Build()
{
if (_objectElement == null)
{
throw new InvalidOperationException("A manifest has not been set on the builder.");
}
XmlElement keyInfoElement, signedInfo, signatureValue;
var info = new HashAlgorithmInfo(_signingContext.FileDigestAlgorithmName);
using (var canonicalHashAlgorithm = info.Create())
{
byte[] objectElementHash;
string canonicalizationMethodObjectId;
using (var objectElementCanonicalData = CanonicalizeElement(_objectElement, out canonicalizationMethodObjectId))
{
objectElementHash = canonicalHashAlgorithm.ComputeHash(objectElementCanonicalData);
}
keyInfoElement = BuildKeyInfoElement();
Stream signerInfoCanonicalStream;
(signerInfoCanonicalStream, signedInfo) = BuildSignedInfoElement(
(_objectElement, objectElementHash, info.XmlDSigIdentifier.AbsoluteUri, canonicalizationMethodObjectId)
);
byte[] signerInfoElementHash;
using (signerInfoCanonicalStream)
{
signerInfoElementHash = canonicalHashAlgorithm.ComputeHash(signerInfoCanonicalStream);
}
signatureValue = BuildSignatureValue(signerInfoElementHash);
}
_signatureElement.AppendChild(signedInfo);
_signatureElement.AppendChild(signatureValue);
_signatureElement.AppendChild(keyInfoElement);
_signatureElement.AppendChild(_objectElement);
_document.AppendChild(_signatureElement);
return(_document);
}