Archive for category Technology
UPDATE: Google Chrome: Good or evil? — GOOD!
Posted by stephan in Technology, foss, free software on September 2, 2008
UPDATE: You can find the update to this article at its bottom.
Even though Google’s slogan is “don’t be evil” I am not entirely sure whether this also applies to their newest development: the Google Chrome browser.
The announcement over at the Official Google Blog tells us that Google is about to release a Free Software-based browser. When I first read the announcement I wasn’t too impressed reading that Google has actually built a browser, this was logical and I have been expecting this move for years. Also, reading that they based their browser on Free Software didn’t impress me too much either, but then I found the comic.
Debian GNU/Linux 5.0 (”lenny”) on a Samsung P55-Pro T8100 Sevesh
Posted by stephan in Technology, foss, free software on August 22, 2008
I have recently bought a new laptop, a Samsung P55-Pro T8100 Sevesh. As I was not able to find an installation report for this model anywhere on the internet I thought writing one myself is a good idea. This way people interested in getting this laptop or installing GNU/Linux on it can get some information.
The article covers both the hardware configuration of the laptop itself, a list of which features of the laptop do work and which don’t (do not be afraid, most things work perfectly well out of the box) and finally a short installation report.
Is trying to fix (E)SMTP really worth it? [part 2 - infrastructure]
Posted by stephan in Technology, observations on July 3, 2008
[digg=http://digg.com/security/Is_trying_to_fix_E_SMTP_really_worth_it_part_2]This article is the second in my series about the flaws of (E)SMTP, the whole Internet mail infrastructure and how it could possibly be fixed. The main focus of this part is a new approach to the infrastructure which should help making emailing more secure, reliable and less spam-prone.
The first article can be found here and points out flaws and problems in the current systems.
Why are hardware manufacturers keeping specs to themselves?
Posted by stephan in Technology, foss, free software, observations on April 6, 2008
This is one question I have been interested in ever since I started using GNU/Linux.
Just think about it for a moment. About 20 years ago you got specifications for pretty much every piece of hardware you bought. You were given exact instructions on how to use the hardware you just bought, not only how to install it. Things have changed since then.
If you buy any piece of hardware today you actually have to expect not to get any documentation on how to “talk” to your new toy. You are only given a CD (sometimes even only a link to a homepage) containing drivers for a few specific operating systems, usually only Microsoft Windows.
Now I am no driver hacker and so I probably wouldn’t be able to implement a driver for anything on my own anyways, but the Free Software community would largely benefit from hardware documentation, as there are a lot of capable driver hackers out there.
This is not a problem that only affects the Free Software community though. There are a lot of pieces of hardware which do not work on recent proprietary operating systems anymore due to lack of support by its manufacturers.
At least this problem would not exist for Free Software operating systems, such as GNU/Linux, if hardware makers would publish documentation of their hardware. The people still using devices which are well beyond their end-of-life could implement drivers on their own, not being dependent on anyone.
What I am really wondering about in this case is why hardware companies are unable to coin standards for accessing devices of the same class. It works perfectly well for USB (take USB mass storage devices as an example) and I do not understand why there can’t be standardized interfaces to other hardware, such as network adapters, as well. On a very-low level these standardized interfaces do work. Just think of PCI, PCI Express or AGP.
Actually, if you think about this for a few more seconds you should realize one thing: Having standardized interfaces for devices of the same class would cut a lot of costs for hardware makers. Why? Oh well, if they design a brand new networking chip and still implement the given standard there would be no need of writing a new driver. Wait, there would be no need for per-device drivers at all. Implementing a common driver that accesses the standardized interface would be enough, for a whole range of devices.
So what am I asking of hardware makers? I would love to see companies creating devices of the same class to get together, create standardized interfaces, publish them and implement them in their new devices.
I know, this is not likely to happen anytime soon, so a more realistic approach is asking for Free Software drivers and/or documentation.
Personally I have stopped buying hardware which “works” with GNU/Linux, I have come to the point where I try only to buy hardware which either comes with Free Software drivers from the manufacturer or documentation which allows implementation of Free Software drivers.
This is probably the best way of showing these companies what you demand: Freedom.
Is trying to fix (E)SMTP really worth it? [part 1]
Posted by stephan in Technology, observations on March 27, 2008
[digg=http://digg.com/security/Is_trying_to_fix_E_SMTP_really_worth_it_part_1]
This one question has been in my mind for quite some time already. I mean, everyone uses SMTP (knowingly or not) when sending out emails and everyone sending emails also knows what SPAM is and receives SPAM messages.
However, few know how old SMTP actually is, and that, even though it serves everyone well, it has been designed in a time when everyone was thinking of Spam as canned meat. Back in 1982 SMTP was a great achievement and a lot of kudos should go to its creators, but now, in 2008, SMTP has become more of a liability than a great tool.
Originally, I wanted to write a single article covering all shortcomings of SMTP and possible solutions to these problems, but while writing the article a lot of text came up, so this is the first of two articles I am going to write on this topic. The first part is about the problems with SMTP and how fix-ups for SMTP are, even though they do work to some extent, a proper solutions to today’s issues.
Due to the way SMTP was designed and the way the Internet was back then it is prone to various things, like SPAM messages, sender spoofing, data manipulation and so forth. A few attempts have been made at fixing some of the shortcomings of SMTP, like ESMTPA (SMTP-AUTH) or SPF, Callback Verification, and DKIM, but none of them has really fixed all problems that exist and all of these modifications are in my opinion mere workarounds. Let us have a look at why both SPF and DKIM fail to fix the all problems SMTP has right now.
How to reject mails containing OOXML attachments using Exim4
Posted by stephan in Technology, free software, personal on March 27, 2008
I finally did it. I modified my Exim’s configuration to reject any mail with an OOXML attachment (ie. docx, pptx, xlsx).
There are two main reasons for this step. First of all I am not able to open these files and I believe I will not be able to do so and get them properly rendered anytime soon. Secondly, people using the new Microsoft Office suite seem to be ignorant enough to think everyone is able to view those files, which is not the case.
I am trying to make one point here:
People sending emails to other people should always send files in internationally standardized formats (open formats), such as ODF or PDF, so that everyone is able to open them and use the attachments. Also, I am trying to make people sending out emails in those formats aware of the fact that not everyone can open them, not everyone wants to invest a lot of money in new applications and that some people generally prefer Free Software and that there is no way of using those files using Free Software right now.
Enough for the introduction, I wanted to explain how to achieve this behavior using Exim4:
deny message = Message contains attachment of unwanted type ($found_extension)
demime = docx:pptx:xlsx
Putting this snippet in the acl_check_content section of your exim4.conf should do the trick.
Oh, and while I am at it, you can easily use this snippet to drop mails with other attachments, based on the file extension.
For example, in order to reject all mails containing WMV files just use demime = wmv.
Note that this snippets checks for a specified file extension instead of a MIME type. People still can get mails through in those formats if they modify the file extension, so do not use this method as a security measure.
