Zac Stewart

Zac Stewart

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Establish Your Encrypted Channels Now


The purpose of this post isn't to bemoan the expanding surveillance state, warn of impending civil liberty revocation, or even to make you feel paranoid. I only want to talk sensibly about a few tools that we should all be comfortable using and know when we should use them.

There may come a time in your life wherein you will need a private, encrypted channel to communicate with someone, whether it's your loved ones, your employer, a reporter, your lawyer, whatever. At some point, you may urgently need to do so. Even more importantly, there may come a time when someone needs to contact you privately.

When said time arrives, it may be difficult to establish that channel in a timely manner. You don't want to be groping in the dark for a way to send that damning report of an impending disaster at a nuclear plant to a watchdog group, or flipping a coin over whether to trust the authenticity of the key signing those rebel dispatches, or hell, sending some racy, career destroying photos by email in the clear.

If the top man at the CIA having his private communications breached isn't enough motivation to take good look at your own privacy, then nothing I can say is. So, put away your tinfoil hats and lets go!

Off-the-Record Instant Messaging

OTR is probably the easiest one and there is absolutely no reason you shouldn't be able to do this one now–right now. As soon as you finish this section, go do it.

It's as easy as installing Adium (or Pidgin if you're not on a Mac), signing into your preferred messaging service (Google chat, AIM, etc…), going to the Advanced preference pane, Encryption, and then generate a private key. Have your partner do the same.

Initiate an encrypted OTR chat with them, accept and verify their key (provided that you're sure it's them). And next time you need to converse privately, "Initiate Encrypted OTR chat." Messages will be passed as encrypted blobs in the clear. If you want to see one, sign in with another client while in an OTR session and look at the messages coming from your partner.

GPG Encrypted Email

Your email is not private. At all. There's not even a paper envelope surrounding it to shield it from prying eyes, making "mail" a misnomer. For now on, think of it as an epostcard. Anyone who happened to handle your message in between you and your intended recipient has potentially read it.

GPG is an open source implementation of the OpenPGP standard, and many mail clients provide built-in support or add-ons for it.

On OS X, you can install it with Homebrew (brew install gpg). Every flavor of Linux I've ever used provides GPG. It should be available via your package manager. Windows users should look into Gpg4win.

To create your key, run gpg --gen-key. You will be guided through a series of questions. In order for someone to send you an encrypted message, they need your public key. To get that, run gpg --armor --output pubkey.txt --export 'Your Name'.

Publish this thing as broadly as possible so that anyone who ends up needing it doesn't have to go hunting for it. For instance, I keep my key in a public gist. You can also publish it to a central keyserver: gpg --send-keys 'Your Name' --keyserver hkp://subkeys.pgp.net.

GPG can be used to accomplish a lot more than just email encryption, though. You can use it to encrypt any data, and since it can be used like any other UNIX utility, you can incorporate it into larger, more complex workflows with a little shell fu. Check out this more detailed guide by Paul Heinlein.

Private Browsing

I don't recommend that you–nor do I myself–use Tor or a VPN on a constant basis, but these should be two tools that you have at your disposal and are comfortable using. Depending on your circumstances, you should evaluate which is the best solution for you.

If you are abroad in a country where it's safe to assume you are snooped on, it's sensible to be running a VPN back home. You can even run one on a Raspberry Pi. In addition to a secure tunnel back to your home internet connection, a VPN gives you the added benefit of having LAN access to your devices at home.

Paid VPN services can be very useful, but should not be considered a way to perpetrate crimes without a paper trail. Providers are typically businesses who will comply with investigators to the full extent of the law. However, if you choose a VPN provider from a jurisdiction where your activities are not illegal, they should have no reason to reveal your identity. Jurisdiction arbitrage is part of the game here.

Tor is an anonymity tool. Not only does it let you browse the internet as a nameless, shady drifter, but it gives you access to a darknet–a shadowy place not accessible from the normal internet. You're on your own here; explore at your own peril. The downside to Tor is that it's very slow.

Donate to the EFF

These tools are all bandaids for a bigger problem we have: the corrosion of civil liberties. They are priceless, but we need to put up more than a technical defense. Skip a few lattes and make a generous donation to an organization that's fighting for your rights.