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It has now been a couple of weeks since I bought my HTC Wildfire. Within this timespan I've become quite taken by this smartphone, the "mini HTC Desire" as it has been called. Comparing to Desire, it's true that the 3.2" QVGA screen isn't as great as the 3.7" AMOLED screen and that Desire's got the Snapdragon processor, otherwise it's a pretty close race if you look at the specification of the two models. Keep in mind that Wildfire is cheaper than Desire, too.

This is actually my first smartphone (yes, I know it's a bit late but that's how it is anyways) and now I'm simply addicted to having a somewhat good internet connection constantly available; automatically checking some mail accounts every 15 minutes, updating the RSS feeds, synchronizing contacts and calendars (Google, Facebook, and Twitter), and a lot of other stuff. I also use the phone as an MP3 player via my Bluetooth headset - flawless. One of the only bad things about the device is the battery duration time, which of course depends upon the usage. But even though I turn off WLAN, Bluetooth, and GPS (when I don't use them, that is) I still have to charge it every evening more or less.

In 1985 Sleator & Tarjan developed the self-adjusting Splay tree data structure. It is a binary search tree which implicitly reorders and readjusts itself by the use of so called splay operations. Regular operations such as insert, delete, lookup, min, max etc. all take amortized time O(log n), where n is the amount of nodes in the tree. The Splay tree is most efficient when a sequence of operations are carried at which point it rivals other binary search trees.

In the previous two posts (Exploiting SMB on Windows and Stealing a photo from a remote webcam) about using Metasploit to obtain access to a remote computer, the focus remained mostly on gaining access and then dropping into a shell locally or transferring back a picture from the webcam. This time we will take a different approach.

Ever wanted to capture a photo from a remote webcam? Like from one of your friends perhaps. Probably if you've a little hacker in your belly.. This is another demonstration of the use of Metasploit like I did in my previous article Exploiting SMB on Windows. Therefore, I won't talk about installing the framework and running the supplied program msfconsole.

Be careful who you give out credentials to if you're running SMB (also known as "Microsoft Windows Network"). It might just be that this person is malicious. Let's assume we wanted to be that person in order to show what an attacker would be able to do.

Picture yourself at a LAN party or the like where somebody wanted to share data, but only to distinguished individuals. Now imagine that we are one of these people and are supplied with the username "Individual" and password "Important". This situation is plausible.

Just yesterday my friend FBH gave me an idea. When you run an OpenSSH server on some machine you will, typically, employ security by obscurity by choosing a different port than 22. This is because hordes of bots, which roam the internet, will attempt to login frequently. Why not have some fun with these bots then? I mean, they will still try port 22 but unfortunately nothing is listening there any longer..

As a little project on the side I have created a CAPTCHA generator suitable for all kinds of human-interaction validation. Below is a test, can you read it?

It can draw random lines, random ellipses, set the background, and, of course, put a string of text onto the image using random colors, character angles, and TrueType-fonts.

A live demo is available here.

So the other day I happily opened the lid of my MacBook expecting it to return from its sleepy state. But it didn't. No, instead it did some bogus scans on the DVD and nothing visual appeared on the screen. It looked like something inside of it had short-cutted and died. The first thing I tried was to turn the computer off and on several times, just to see if it was a minor glitch. That didn't work. Then I tried giving it AC. Same result. Afterwards, I let the Mac "rest" without the battery and AC for about 15 minutes. But putting the whole thing together again didn't yield a success either.

Just the other day, I was confronted with a problem at the university where disk I/O operations were unavoidable. It is a fact that the HDD is slower than RAM, of course, so a mounted FS in RAM was used instead. If one has tried this in FreeBSD or Linux before then this is quite similar and just as easy.

To create a RAM disk the following is done:

% hdid -nomount ram://SECTORS

In 1996 it was discovered that the MD5 hash-algorithm had problems. Furthermore, an algorithm was devised to generate these collisions in 2005.