public virtual void UpdatePdfSignatureAppearance(IPdfPreSigningSession pdfPreSigningSession, PdfReader pdfReader, PdfSignatureAppearance pdfSignatureAppearance)
{
pdfSignatureAppearance.Location = pdfPreSigningSession.Location;
pdfSignatureAppearance.Reason = pdfPreSigningSession.Reason;
pdfSignatureAppearance.CryptoDictionary = new PdfSignature(PdfName.ADOBE_PPKLITE, PdfName.ADBE_PKCS7_DETACHED)
{
Reason = pdfSignatureAppearance.Reason,
Location = pdfSignatureAppearance.Location,
Date = new PdfDate(pdfSignatureAppearance.SignDate)
};
}
private PdfPKCS7 GetPublicKeyManager(IPdfPreSigningSession sessionData)
{
var chain = new X509Chain();
var certificates = new List <Org.BouncyCastle.X509.X509Certificate>();
chain.ChainPolicy.RevocationFlag = X509RevocationFlag.EndCertificateOnly;
chain.ChainPolicy.RevocationMode = X509RevocationMode.NoCheck;
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.AllFlags;
chain.Build(sessionData.UserCertificate);
foreach (var chainElement in chain.ChainElements)
{
certificates.Add(DotNetUtilities.FromX509Certificate(chainElement.Certificate));
}
return(new PdfPKCS7(null, certificates, sessionData.HashAlgorithm, false));
}
public virtual IAuthenticatedAttributes CreateAuthenticatedAttribute(IPdfPreSigningSession pdfPreSigningSession)
{
var pdfContentBytes = File.ReadAllBytes(pdfPreSigningSession.FilePath);
using (var PdfReader = new PdfReader(pdfContentBytes))
{
using (var pdfStamper = PdfStamper.CreateSignature(PdfReader, null, '\0', pdfPreSigningSession.FilePath, true))
{
var authenticatedAttributes = new AuthenticatedAttributes();
var publicKeyManager = GetPublicKeyManager(pdfPreSigningSession);
authenticatedAttributes.PdfSignatureAppearance = pdfStamper.SignatureAppearance;
UpdatePdfSignatureAppearance(pdfPreSigningSession, PdfReader, authenticatedAttributes.PdfSignatureAppearance);
authenticatedAttributes
.PdfSignatureAppearance
.PreClose(new Dictionary <PdfName, int> {
{ PdfName.CONTENTS, SIGNATURE_ESTIMATED_SIZE * 2 + 2 }
});
var pdfSignatureAppearanceData = authenticatedAttributes
.PdfSignatureAppearance
.GetRangeStream();
authenticatedAttributes.DigestedData = DigestAlgorithms
.Digest
(
pdfSignatureAppearanceData,
pdfPreSigningSession.HashAlgorithm
);
authenticatedAttributes.Value = publicKeyManager
.getAuthenticatedAttributeBytes
(
authenticatedAttributes.DigestedData,
null,
null,
CryptoStandard.CMS
);
return(authenticatedAttributes);
}
}
}
