Origami

Overview

This is a fork of the original origami project.

I have added a way to sign PDF files with an external provider, such as the Austrian "Handy-Signatur" (Mobile Phone Signature)

Currently only PDF PKCS#7 signatures are supported, however I plan to support PAdES (PDF Advanced Electronic Signatures) as well.

Requirements

You can review requirements and other important information at the original origami project.

Quickstart

This fork adds two new methods for PDF manipulating.

base64_string = pdf.prepare_signature(
      name: "John Doe",
      location: "Somewhere",
      contact: "john@doe.com",
      reason: "PDF Signature Test",
      method: Signature::PKCS7_DETACHED,
      content_size: 4096)

prepare_signature adds the signature object to the PDF document and prepares it for signing. You can specify some parameters which are shown when opening the PDF with a PDF reader (name, location, etc). This method returns the PDF as a Base64 encoded string, excluding the signature placeholder.

insert_signature(signature_base64)

This method inserts the signature back into the PDF (at the /Content object).

Code example here.

Flow

Read or create PDF document
Prepare the signature
Send Base64 content to external signature provider
Insert the signature into the PDF
Finish

Known Bugs

When saving the PDF after preparing it and re-reading it from disk, the Signature Object can get scrambled up, which invalidates the ByteRange array and also the signature.

Helpful Literature

Digital Signatures in a PDF

Portable Document Format Reference Manual Version 1.3

License

Origami is distributed under the LGPL license.

moritzgloeckl / origami

readme