Question

I have a .net web application, using C#, which will allow users to upload a file, we need to encrypt that file to be more secure, rather than leaving the file as is on the server, so will also need a way to decrypt the file so users can view it from the web application. can someone recommend a way to do this? The files types may vary, but for now they only want .pdf files to by uploaded, if that matters.

Thank you.

Answer 1

Follow the following steps:

1. Use AES encryption
2. Generate and store AES keys and IVs as varbinary in the database
3. Encrypt the file stream that comes when someone uploads a file
4. Add a general handler *.ashx and, in it, query the database to get the AES keys and IVs
5. Write to the response stream the decrypted bytes