Category: General

Keep your email secure (and what just doesn’t work)

The best way to keep your e-mail address secure from evil spam bots is some kind of javascript and obfuscation, which unfortunately isn’t always available. There are enough alternatives though.

Usually people tend to replace the ‘@’ with some short replacement like ‘{at}’ or ‘bij’. This just doesn’t help.

Any programmer with a bit of knowledge of regex can create a program that scans for domain names and interprets every small bit of text in front of it as an @ sign.

Some smarter people also replace the dot. This works, unless your email-host uses a easily recognizable TLD (.com) or domainname (gmail.com).

Also putting ‘SPAM’ in your email-adress some.personREMOVETHISFORSPAM@foo.bar is easily filtered.

Best thing is to use something out of the box.

For instance, my email address is X@Y, where:
X = bas.westerbaan
Y = gmail.com
Also I’ve got an email-address on w-nz.com, namely bas.westerbaan.

Or even maybe w-nz.com@bas.

Anonymous comments disabled re-enabled

I’ve disabled anonymous comments for my blog, because my blog is spammed with ~100 spam-comments a day — it seems they’ve worked around Hashcash 3.0. I’ll look into this a bit more when I’ve got time. Sorry for the inconvenience.

Update Seems it were nasty trackbacks instead of comments. So I just disabled trackbacks. You can comment again.

GMail`s strange perception of EMail size

I’ve just downloaded my whole GMail account via POP3. Each message is stored as-is, including headers and attachments in base64, in a seperate file.

du -ms on the folder with all emails tells me:

2117

While GMail tells me:

You are currently using 2079 MB

Why this difference, I asked myself. Was there a difference in the way e-mail was stored? Actually I stored my e-mail very inefficiently. E-Mail is 7bits encoded — every character is 7 bits — where my FS (like virtually every other) stores each character in a 8bits. Lets calculate the actual size of email on my disk:

>>> 2117 / 8 * 7
1848

It gets even more absurd considering that the most part of that space is used by attachments in emails, which are encoded in Base64, which uses 6bits per character. At least 50% of these 2GB are attachments, thus:

>>> 2117 / 8 * 6.5
1716

Why am I using 2079MB according to GMail?

GMail wouldn’t require 2079MB for my emails, they probably compress all attachments and old mails, they won’t even come near that 2079MB. It would therefore seem logical that they would use the real size of all emails — which should at least match the 1848MB or 2117MB, but it doesn’t.

Anyone got a good guess?

Disclaimer: This isn’t in any way meant to be anti-gmail — I love gmail, everyone loves gmail! I’m just curious.

Last.fm

last.fm is a (omfg! web2.0) service that tracks the music you play. You just install a plugin for your favourite music player and all songs you play will be send to the site. They will create nice charts, make recommendations and lots of other fun stuff.

Oh look, it even has got syndication! (my recently played tracks)

You can see nice charts about my music here.

Upgraded to WordPress 2.0.1

Just upgraded to WordPress 2.0.1, which was way too easy:

# in my blog.w-nz.com htdocs folder
wget http://wordpress.org/latest.tar.gz
tar -xvzpf latest.tar.gz
cp wordpress/* . -R

Visit the upgrade script, which consisted out of one simple click and I was done.

Great stuff.

PS. I reuploaded my logo and google analytics code too, but they don’t count, really (even though they consisted out of more work that the rest of the upgrade).

Xgl

After a long night wrestling with alfa source code, I’ve managed to install Xgl.

Xgl ownageXgl transparency

Xgl is a Xorg-X11 layer that uses openGL to achieve some nice stunning effects.

One of these is to be able to switch desktops by pressing ‘Ctrl+Alt’ and dragging your desktop-cube.

There are a lot of other things that I can’t show with screenshots. Take a look at the Xgl release post. These things include that all forms behave flexible. If I drag a form it’s like it’s made of rubber instead of concrete. Also every form pops up gently animated. There’s also a mac osX expose-clone, which is really helpfull.

If you want to install it yourself then the gentoo wiki article and hanno’s blog post should be very helpful.

Mulholland Drive

Mulholland Drive is a great film. If you haven’t watched it yet, just watch it.

Those lucky enough to be astounded and puzzled by the film have all came up with their own interpretation of the movie.

The most common interpretation is that either the first or the last part is a dream of the opposite part. I’d have to disagree with that for both parts are just too bizarre to be real. However, both parts are pseudo-opposite.

Just take the ‘119’ on the firetruck for instance that hasn’t been mirrored, but still reversed.

It keeps you thinking in any case.

PHP’s hidden treasures

I’ve complained a lot when I worked with PHP about PHP’s terribly inefficient design; I’ve complained about it, just because it was PHP. The things I missed most in PHP, it seems, were actually there all along!

Behold shared memory and yet more IPC.

One reason PHP really sucked was that you need to load small data from and to databases or files if you want to share it between page views. The whole concept of handling a request per page view is ridiculous too, IMO.

With those two libraries however, PHP pages could be way more efficient.

I wonder why the big PHP software haven’t used it. Lets hope it isn’t portability.

Beacon with eggs and …

Spam, again on this blog.

It seems those nasty spammers are now using actual people (or an automated browser) to post spam comments, subverting the protection wp-hashcash delivers.

Luckily it are only about two per day, which is very managable, but still annoying.

Like DRM and most other copyright protections, SPAM protection is inherently insecure, for the original openess required to allow a not-spammer to use them is, well, too open.

One interesting thing is that we can fight back now that they are using full javascript VM’s. Matching the spam-ip and letting it execute a rather ‘memory inefficient’ little program would certainly make me smile.

mail.w-nz.com

I’ve successfully installed vpopmail, qmail and courier today, after some hours of work on this server.
From now on you can send e-mail again to @w-nz.com adresses, which won’t end up in /dev/null. (like bas.westerbaan@~)

To the users of the server: if you want an email-address, mail me.

While testing my smtp server whether it would receive incoming email properly I was harshly confirmed by it being spam instead of my test mail entering my mailbox first:

Hello Spam!
It’s pretty funny to see spam junk in an ancient text-mode mailing program.

If anyone experiences problems with any application not mailing you any verification as it should, please email me. It could very possibly be that the qmail-send isn’t configured properly to allow unauthorized local mails.

Update: More good news, the amount of RAM on my virtual server has increased to 120MB! Which means that my server won’t be swapping instead of working all the time anymore.

Welcome to lighttpd

After a long afternoon I’ve got lighttpd to work with my current apache based layout.

This means I can choose whether to run apache or lighttpd.

Lighttpd is a webserver, like apache. The key advantage of lighttpd over apache is that lighttpd is very light on your server. It uses a lot less memory, which is very nice espacially when considering that my server only has got ~90mB of memory.

The drawback of lighttpd is that it is light and doesn’t support as much as apache does.

It doesn’t do .htaccess files. Everything needs to be configured in the lighttpd.conf, which doesn’t support everything, or at least not in the same way as apache does.

However, lighttpd is pretty easy to configure when you get the hang of it.

One particulair pain in the ass is getting old mod_rewrite using .htaccess to work, for instance the one used by wordpress of this blog.

I’ve added this in my lighttpd.conf:

$HTTP["host"] =~ "blog.w-nz.com" {
url.rewrite = ( "^/(page|archives|comments|search|feed)/" => "/index.php?error=404" )
}

One interesting thing to note is that the configuration file is nothing more than a script being executed for each request.