| Low tech things that can help: It is much better to use cd-roms than usb (and to destroy/shred the cd roms after you pull them out of the secure machine you use to read data). If you need to send data, using a second air gapped machine for that is probably best. This prevents a crafted file that gets root on the reading machine from phoning home unrelated documents. Be sure to cut all the speaker/mic/wifi/bt lines, use an lcd (not crt), and run off a UPS battery, not the grid. Use the computer in a windowless room. This prevents 90’s era surevelliance vans from reading the data from the curb. When you are not using the machines, store them in a tamper-evident box. One time pad encrypt your key pair, and keep the one time pad key with you. This makes it more expensive to tamper with the machines in a way that will cause them to allow the attacker to later steal them and get the documents / keypair. Also, remember rubber hose cryptography. https://xkcd.com/538/ You might be better off using something more mainstream, and blending with the crowd. For instance in recent civil wars, civilians turned mostly to stuff like facebook, fledgling chat apps, burner phones/identities, etc. I guess the point of this long-winded comment is that nothing I mentioned has anything to do with special software. If you’re going down the path of using the linked system, be sure you understand what it can (and can’t) do for you. |