I have Ubuntu 19.10 with full disk encryption. The encryption is effective as long as the system is turned off or restarted. Otherwise the data is unencrypted behind a locked screen which may not be very secured.
I wish to protect against:
- mechanisms that bypass screen lock (I have disabled SysRq, but there might be other ways too)
- cold boot attacks
- attacks through DMA, network, WiFi/Ethernet, physical ports, etc
What's the best way to proceed? Can I have a home encryption on top of full disk encryption, and set the screen lock such that the same password will unlock and decrypt the home drive (I don't want to enter two passwords)?
Is there any secure screen lock (no bug, no vulnerability against X11 crashes, etc)?
The OS + encryption should be able to protect the system 100 percent (except for cold boot attacks which mostly aren't practical: the data rapidly deteriorates).