Var msrp = await _clientMID.The US Federal ESIGN Act defines an 'electronic signature' as an electronic sound, symbol, or process, attached to or logically associated with a contract or other record and executed or adopted by a person with the intent to sign the record. Call external webservice to sign blankSignature.GetDocBytesHash() Stamper.SignExternalContainer(blankSignature, 8192*2+2) New PdfCanvas(appearance.GetLayer2(), stamper.GetDocument()).AddXObjectFittedIntoRectangle(sigAppearance.GetXObject(), sigAppearance.GetRectangle()) Stamper.SetFieldName(new GetSignatureToSign(stamper.GetDocument()).GetSignatureName()) Var sigAppearance = new SigAppearance('stamp1.svg', (X509Name.CN).Cast().FirstOrDefault() ? '', DateTime.Now, 'Sign', stamper.GetDocument()) Īppearance.SetPageRect(new (sigAppearance.GetPosition())) Var appearance = stamper.GetSignatureAppearance() Var stamper = new PdfSigner(pdfReader, stream, new StampingProperties().UseAppendMode()) Var blankSignature = new BlankSignatureContainer2(PdfName.Adobe_PPKLite, PdfName.ETSI_CAdES_DETACHED, chain)

creating empty signature container, getting file digest and hash X509Certificate chain = await _signPdf.GetMidChain(certificate.Cert) Using (PdfReader pdfReader = new PdfReader(ms)) Using (MemoryStream ms = new MemoryStream(Convert.FromBase64String(value.pdfFile))) //pdf file to sign using (MemoryStream stream = new MemoryStream()) SignDic.Put(PdfName.SubFilter, subFilter) ĭocBytesHash I sent to external webservice to sign with qualified signature.

Public virtual void ModifySigningDictionary(PdfDictionary signDic) PdfPKCS7 sgn = new PdfPKCS7(null, chain, HASH_ALGORITHM, false) ĭocDigest = DigestAlgorithms.Digest(docBytes, DigestAlgorithms.GetMessageDigest(HASH_ALGORITHM)) ĭocBytesHash = sgn.GetAuthenticatedAttributeBytes(docDigest,, null, null) ĭocBytesHash = sha256.ComputeHash(docBytesHash) Public virtual byte Sign(Stream docBytes) Public BlankSignatureContainer2(PdfName filter, PdfName subFilter, X509Certificate chain) Private const String HASH_ALGORITHM = DigestAlgorithms.SHA256 I cant find why Foxit PDF Reader show me my signature of signed file is invalid.įirst I insert blank signature container to pdf public class BlankSignatureContainer2: IExternalSignatureContainer

Foxit e signature