Best Practices in Protecting Amazon S3 Files?
For example, I have a website with User A and B.
Both of them can login to my website using my own login system.

How do I make certain files from S3 accessible only to User A once he login to my website?

Note: I saw "Permission" in AWS Management Console with "Authenticated Users" option but it seems that it's meant for other S3 users only, is it something I can use to achieve my goal?
Best Practices in Protecting Amazon S3 Files?
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For example, I have a website with User A and B.
Both of them can login to my website using my own login system.

How do I make certain files from S3 accessible only to User A once he login to my website?

Note: I saw "Permission" in AWS Management Console with "Authenticated Users" option but it seems that it's meant for other S3 users only, is it something I can use to achieve my goal?