I'm currently tasked with securing our documents stored in our NAS.
Basically, the minimum requirements that is needed are;
1) Watermarking Ability(Any file viewed/downloaded or printed will have the user's name, IP and Time/Date watermarked on the document)
2) Restriction(Not all users can view/download certain files)
I've toyed with XRDP and Ubuntu, so users have to remote into the desktop to be able to access the files, I've even installed Screenlets and used a widget to display their name on the screen but, I've been having issues getting it to work properly.
Can anyone recommend me a good solution to secure the documents? Preferably open-source and with an online document viewer, so there is no need to download the document to view it.
EDIT: Additional information. The document types will be mainly PDF, doc, docx, ppt, pptx, odt, etc. I've tried multiple solutions but, most of them either don't have the watermarking capability or, are not on-premise.