Recently, I have been trying to find an open source alternative to pdf signing instead of using Adobe Acrobat. It has been much tougher than I thought.
I made a PKCS key using CACert and XCA and I added that to the Windows certification directory. But when it came to programs to sign documents with it, I struggled to find good options.
Libreoffice was one, but when I imported the document it did not seem to recognize that the pdf was a form and did not let me sign the areas specified in the form I was trying to sign.
So I went to Okular, which was easier at first. It recognized the QT fields, but when I tried to sign in the specified locations, it said “There are no available signing certificates.” When I checked the manual it said that the Poppler library is used to sign PDFs. I tried downloading “Poppler” through the unofficial Windows setup, but I have no clue how to set up my PKCS key so that it is recognized by the program.
I’m feeling kind of lost here and I have not been able to find helpful documentation on how to continue. Does anyone have any advice? Thank you!