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Idag upphör brevhemligheten i Sverige

Idag börjar FRA-lagen att gälla. Från och med idag får FRA koppla in sina kablar och börja läsa vår e-post. Det enda sättet att skydda sig är genom kryptering. Se min tidigare post om hur du kan göra för att kryptera din email-trafik. För er som inte använder Mutt (gör inte alla det?) kan jag rekommendera Enigmail som plugin till Thunderbird.

FEniCS in Debian

All FEniCS packages including DOLFIN have made it into Debian (sid). Thanks to Johannes Ring and Christophe
Prud’homme for their efforts with the packaging. I hope this means the packages will make it into Ubuntu 10.04.

Infringement of FEniCS Trademark

We just got contacted by Kenyon & Kenyon, a company that seems to specialize in “intellectual property litigation” (one of the lowest forms of activities).

Apparently, someone does not want us to use the FEniCS name.

I don’t know yet if this is a scam or if it is “serious”.
Read on for more information in
this thread.

Posting to WordPress from Mutt

This is pretty cool. I can post to WordPress directly from Mutt.

Why the Mac sucks

One of my students who wishes to remain anonymous… is running Apple Snow Leopard on a shiny new MacBook. I must admit it’s a nice looking machine with a very glossy screen. But it seems to be completely useless for doing any kind of real work. Although it’s possible to make it work in theory (as demonstrated by one of my postdocs), it seems very difficult in practice (as demonstrated by one of my PhD students). The Mac seems to give an equivalent experience to what I had with Slackware GNU/Linux 12 years ago. Most everything must be built from source, PATHs are always wrong and you need to be an expert to do even the simplest things.

Short time vs long time accuracy

Here’s a simple example of a model that is short time inaccurate but long time accurate:

x(t) = y(t) = z(t) = t

This is a model of the following chaotic system:

x’ = s (y – x) + 1
y’= r (x – t) – (y – t) – (x – t) (z – t) + 1
z’ = (x – t) (y – t) – b (z – t) + 1

Here, s = 10, b = 8/3 and r = 28 and this is of course a trivial modification of the famous Lorenz system.

This is a friendly comment on a recent blog post by Claes.

The solution of the chaotic system is shown in the figure below which approaches (relatively) the solution of the simple model x = y = z = t for large values of t.

Email encryption with mutt

As everyone is aware of by now, the Swedish FRA will soon “start” monitoring (scan, filter, read) all private email traffic crossing Swedish borders. This is not only a very bad idea, it is also very obviously a breach of the Swedish constitution; to be precise Regeringsformen 2.6 which very clearly states that private communication is protected:

Varje medborgare är gentemot det allmänna skyddad mot påtvingat kroppsligt ingrepp även i annat fall än som avses i 4 och 5 §§. Han är därjämte skyddad mot kroppsvisitation, husrannsakan och liknande intrång samt mot undersökning av brev eller annan förtrolig försändelse och mot hemlig avlyssning eller upptagning av telefonsamtal eller annat förtroligt meddelande. Lag (1976:871).

Anyway, there is a simple solution. Just encrypt your email. Below I demonstrate how to set up mutt (the email client for real men) for easy encryption. For everyone else, I recommend Enigmail.

1. First, use Seahorse to generate a key-pair.
2. Exchange keys with your friends or upload your public key to a keyserver. (Seahorse will help you with this.)
3. Add the following lines to your .muttrc:

# Sign all outgoing messages
set crypt_autosign=yes

# Encrypt messages to all recipients in keyring
source ‘~/local/etc/mutt/generate-crypt-hooks.py|’

# Store unencrypted copies of outgoing messages
set fcc_clear=yes

# Remember PGP passphrase for 1 hour
set pgp_timeout=3600

You will also need the following script. Store it in a suitable location and adjust the path above accordingly:

#!/usr/bin/env python

import commands

# List keys from GPG keyring
gpg_output = commands.getoutput(“gpg –list-keys”)

# Extract email addresses
emails = []
for line in gpg_output.split(“\n”):
     if not “@” in line: continue
     email = line.split(“<”)[1].split(“>”)[0]
     if not email in emails: emails.append(email)
     emails = “|”.join(emails)

# Print mutt send-hook
print “send-hook ‘^~C \”(%s)\”‘ ‘set pgp_autoencrypt=yes; set pgp_autosign=yes’” % emails

The script is based on a Perl script I found here.

Once setup, this will make mutt automatically sign all your outgoing messages and encrypt all messages to recipients found in your keyring. It will also make sure that if you store copies (fcc) of outgoing messages, those copies will be stored unencrypted (so you yourself may read them, not only your recipient).

Code swarm

I just stumbled upon the following excellent visualization of the development of Apache. Well, “stumble” is probably not the right word for something you find on Slashdot. Anyway, if only I could get my hands on the code I could make some fun movies…

Encrypt your emails

Why should you encrypt your emails? Well, simply because if you don’t encrypt your emails someone else will read them, and I’m not talking about the recipient.

In a few days (June 17 2008), the Swedish parliament will most likely pass a bill which gives the FRA (the Swedish NSA) the rights to scan all email communication crossing Swedish borders (which means most our emails). Read more about it here, here, and here.

It is hard to imagine I actually used to vote for one of the parties of the current Swedish coalition government, the Liberals, before they went completely crazy.

At some point, I’ll write on my experience using PGP (GPG) to encrypt my email communication with mutt. For now, here’s my public key:

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.4.6 (GNU/Linux)
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=TXXX
-----END PGP PUBLIC KEY BLOCK-----