Since e.g. SSH keys under Linux are owned by the user who created them, any applications running as the user, e.g. a web browser, should be able to read them from the ~/.ssh
folder.
Say that there is only one user on a system: user A. If another user, B, is added to the system and the only purpose of B is to own and store the SSH and GPG keys of user A, applications running as user A should be unable to read the keys.
When user A wants to use the keys that he/she has chosen to store under user B, what would he/she have to? Would this method of storing keys improve the security at all?
Hence, I want the keys to be usable by user A when they are stored by user B, but I don't want the keys to be readable by the applications running as user A.