Ensuring Secure Data Remains in Memory

Question

On a Linux system, how would you structure a program (C/C++/Python/Java etc) to ensure that a piece of data remains in volatile memory and is never cached to disk or swap?

I'm specifically concerned with security applications where you want to ensure a manually entered password or cryptography key is forgotten and unrecoverable the moment the system loses power, but otherwise remains accessible.

Answer 1

Have a look at mlock(2)/munlock(2)