I would like to print pre-signed documents with a verifiable OTP on it.
I'm a web/system developer, crypto and security enthusiast. Somehow, I'm now the head of HR in a hotel in Congo. As an IT guy, I want to do the most with less work, so for instance I've developped an intranet that automatically generates the required certificates (employer's certificates, training certificates, ...), with my own signature + company's stamp on it, as PDF.
For now, I'm the only one authorized to generate "pre-signed" documents, but it's not hard to scan and crop a document to extract this area, so I'm looking for a way to paste (inside the signature area) something like an OTP to be able to control the validity of a document.
For instance, we assign a given ID to a document, and assign a given OTP-like to the signature on that same document. Then, for anyone in the company, it will be possible to check on the intranet a given ID which will lead to the associated OTP (or the other way around).
Now my question is what would be the best non guessable way to implement it? UUID
s and/or a cryptographic signature
seem to be logical choices, but too long (to paste in the signature area) IMO. Any idea?
Thank you for your help.
PS: I precise "Congo" above because there is currently NO LAW about numeric documents. Everything have to be printed, signed and aknowledged.