58 lines
2.7 KiB
Markdown
58 lines
2.7 KiB
Markdown
---
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date: 2014-06-08T00:00:00-05:00
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title: "Encrypting your e-mails to yourself using GnuPG"
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tags: [en_us, english, free-software, security, privacy, howto]
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---
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It has been a while since I dream of being able to send encrypted e-mail
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to everyone in my contact list. It is still a distant future, but
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fortunately it is getting closer with campaigns like the [Reset the
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Net](https://www.resetthenet.org/). And while I already send encrypted
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messages to a couple of friends, it is always good to discover (and
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share!) some configuration tips to make your life easy :-).
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I use [Gnus](http://gnus.org/) as my e-mail (and news!) reader for quite
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a while, and I can say it is a very nice piece of software (kudos to
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Lars and all the devs!). For those who are not aware, Gnus runs inside
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[Emacs](https://gnu.org/software/emacs/), which is a very nice operating
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system (and text editor also).
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Emacs provides
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[EasyPG](https://www.gnu.org/software/emacs/manual/html_mono/epa.html)
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for those who want to make use of cryptographic operations inside it,
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and Gnus also uses it to encrypt/decrypt the messages it handles. I am
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using it for my own messages, and it works like a charm. However, there
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was something that I had not had configured properly: the ability to
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read the encrypted messages that I was sending to my friends.
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In a brief explanation, when you send an encrypted message GnuPG looks
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at the recipients of the message (i.e., the people that will receive it,
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listed in the “From:”, “Cc:” and “Bcc:” fields) and encrypts it
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according to each recipient's public key, which must be present in your
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local keyring. But when you send a message to someone, you are not
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(usually) present in the original recipients list, so GnuPG does not
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encrypt the message using your public key, and therefore you are unable
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to read the message later. In fact, this example can be used to
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illustrate how secure this system really is, when not even the sender
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can read his/her message again!
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Anyway, this behavior was mostly unnoticed by me because I rarely look
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at my “Sent/” IMAP folder. Until today. And it kind of pissed me off,
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because I wanted to read what I wrote, damn it! So, after looking for a
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solution, I found a neat GnuPG setting called `hidden-encrypt-to`. It
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basically tells GnuPG to add a hidden recipient in every message it
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encrypts. So, all I had to do was to provide my key's ID and ask GnuPG
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to always encrypt the message to myself too.
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You basically have to edit your `$HOME/.gnupg/gpg.conf` file and put
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this setting there:
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```console
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hidden-encrypt-to ID
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```
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That's it. Now, whenever I send an encrypted message, GnuPG encrypts it
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for me as well, so I just need to go to my “Sent/” folder, and decrypt
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it to read.
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I hope this tip helps you the same way it helped me!
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