I have a software which i need to integrate plagiarism checker in it, but this time its not just checking for content, but the document itself.

Explanation: When an admin uploads a book, the book should have a unique id attached to it, so when a user downloads the book using his acct, his acct id is also attached to it and as he uploads outside (other website/blogs), the library system should search the internet for the unique id document, if found it can be traced by the the user.

Who can achieve this?