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Thursday, August 28, 2008

IE8 Beta 2 - inline images, and anything else

With IE8, we finally can "play" with inline images, specially for CSS or other little decorations.

The main limitation is that the length of the data protocol has a maximum fixed length, but even worst is that IE8 apparently introduced the data protocol only for images.

In another scenario,where we would like to use the same technique for other purposes, IE is still the only browser that does not respect standards.

This is an example:

function evalazy(src, callback){
var script = document.createElement("script"),
body = document.documentElement;
script.onload = callback;
script.type = "application/javascript";
script.src = "data:" + script.type + "," + encodeURIComponent(src);

Above function is able to evaluate valid JavaScript code in an asynchronous way, calling a callback, if any, when evaluation has been completed ( kinda load runtime an external script ).

Since functions like atob and btoa are still not standard, the script is evaluated as url encoded string.
But even using a base64 string, the result does not change, IE does nothing, or it could generates an error, the classic could not complete the operation due to error 800a03e8 if the body is not present, and in some case, it could even crash during next script execution.

evalazy("testMe = 123", function(){

In this case the problem is JavaScript, but since the data protocol has been only partially implemented, we will not be able to include every other kind of resource that is not an image.

Hoping I am wrong, and hoping they'll make data protocol more "efficient", let's play with IE8 and its new features, really, and generally, appreciated. Thanks IE8 team :)

Thursday, August 21, 2008

How to crash FireFox 3 with 3 lines of code

Hi there, here I am back from holidays :geek:

Before I'll start to write more interesting stuff, here we have 3 lines of JavaScript that could cause problems to our favourite browser, in this case version 3.0.1

I discovered this problem, already part of the bugs report site, trying to emulate keyboards events using the UIEvents interface instead of KeyboardEvents

var e = document.createEvent("UIEvents");
e.initUIEvent("keypress", true, true, this, 1);

Nice one? See you soon ;)

Tuesday, August 05, 2008

Image Protector, a nice waste of time

I've read right now about another, pointless, attempt, to avoid the classic Save Image As from a website.

Guys, we are in 2008, and I hope that everybody knows what can the simple Stamp / Print button can do, when we are simply watching whatever in our screen.

No way, every tot months, somebody "creates" the ultimate version of an Image Protector, usually based on JavaScript, then "startly pointless" because JS could be easily disabled.

Morevore, this times the trickless trick even requires an excellent library as MooTools is.

Well, since I hate disinformations about techniques to make data truly safe, I can tell you that you need 159 characters to remove the protecion, javascript protocol included.

The funny stuff is that basing the same anti protector over MooTools, since this library is required for the amazing protector, you need even less characters to do the same, basing them on a $$("img") call, instead of document.getElementsByTagName.

Being sure that this technique will be probably adopted from people that do not know a single thing about web or security, and do not know how to implement a basic Watermark, I suppose somebody will implement the same trickless trick, so I prefer to show you the extended link that, if saved in your bookemark, will be able to remove the protection whenever you need, and in a click.

This is the code:


And this is the link:

Save into bookmark, drag there, try the example page, one click in the "bookmarked magic guru crack", and sweat dreams, you can still grab images from those sites that do not have a clue about safe contents :D