My system is protected by Full Disk Encryption.
The weak point of my computer is RAM which lives a bit after computer is off,
containing some important safety information I would like to clean up.
And that's the point, I want to clean or overwrite RAM and shut down my computer just when Ctrl+Alt+Shift+C is pressed.
How to do that?
Just cut the power from your computer before you let the police in. I assume your machines run at room temperature, so the memory content should degrade within seconds.
There is no panacea against cold boot attacks. How would you suggest to identify which parts of memory contain sensitive information? What happens to the application(s) that reserved such a memory region?
On the positive side, there is no known case of a non-experimental cold boot attack.
P.S.: If you're concerned about master encryption secrets being leaked, get a hardware key store where the actual key never leaves the store and all encryption operations are performed on it.
for cleaning cache memory :
sudo sysctl -w vm.drop_caches=3
or
sudo sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
for short-cuts you can make a bash script that do one of these operations.
reference : clean cache memory
as for the ctrl+alt+shift+c i dont know how to do that.
