We produce digitally signed pdf, There is section where end user can verify his signature by provide digital signed document.
We want to fetch digital signature information for this document to display like- Signer certificate details , issuer certificate details . signing reason, name , location , field name of signature and all other to display to user.
Please let me know how I can do this using Aspose.
Thanks, We used your suggested and able to see properties but I not understand the property name in which signature properties are getting bind.
Please see attached screenshot of attached pdf. Properties.jpg (74.2 KB) DSC Signed .Pdf (1.1 MB)
I have highlighted area of properties name, I cannot understand , For example signing date is written against some unreadable property. Do you have any enum list of same with property name and it’s meaning. If you have any then please provide same.
We wanted to extract the Certificate from your PDF document and use a valid PKCS7 object in order to extract SignatureCustomAppearance. Nevertheless, we noticed that no certificate was found in your PDF using the code snippet.
We were able to extract signature however and its other properties can be seen as well e.g. Location, Date, Reason.
using (Document pdfDocument = new Document(dataDir + "DSC Signed.pdf"))
foreach (Field field in pdfDocument.Form)
SignatureField sf = field as SignatureField;
if (sf != null)
Signature s = sf.Signature;
var date = s.Date;
var location = s.Location;
var reason = s.Reason;
SignatureCustomAppearance signatureapp = s.CustomAppearance; // this is null because no customer appearance was used while signing the PDF
Stream cerStream = sf.ExtractCertificate(); // this is null
PKCS7 pKCS7 = new PKCS7(cerStream, ""); // this is null
Would you kindly provide details of the certificate using which this PDF was signed. We will further investigate the scenario why API is unable to extract it and share our feedback with you.
Thanks for quick response. With given code we are able to extract date, reason and location. Still Certificate details, issuer details and field name is not extracted.
I will not to be able to share password but Certificate is from Indian certification authority - Safe scrypt CA - They provide hardware token with DSC in it. Link for same : (https://www.safescrypt.com/)
Please let me know in case something more required.
We have logged an investigation ticket as PDFNET-48511 in our issue tracking system for your remaining requirements. We will further investigate whether your requirements are feasible to achieve with shared document or not and keep you posted with the status of ticket resolution. Please be patient and spare us some time.