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Showing posts from January, 2007

Exploiting Double Free Vulnerabilities...

Alsalam alikom wa ra7mat Allah wa barakatoh Huh!! that's what I said when I first saw that title... but let me explain... Double Free means that you try to free a pointer two times (which is logically can't work). Actually windows SP2 and later (even Vista) this can be done (in somehow) and can actually corrupt the heap (Vista will shout at your face if u did) and that can make you able to use and browse the heap as you want.. Facts to know about how Windows frees your pointers: - There is something called Lookaside buffer (fast access, small size) and another thing is FreeList(slower access, the whole memory). - Chunk is an object of the DataStructure that holds mainly 2 things: pointer to where the next free Chunk is and pointer to the previous free one (think about it like a node in a linked list) - The first 4 bytes of the Chunk is the BLink (BackLink) and the second 4 bytes is the FLink - delete ptr1; delete ptr2; Windows takes your Chunk (for ptr1) and puts it in the Lo

Google Translate... In your site !!

Alsalam alikom wa ra7mat Allah wa barakatoh I wanted to add the Translation service to my website, Google didn't put some code to put to get the Google Translate Service in you page so I had to build mine. Here is the code: Source Code Just put it in your page and it'll get you all the language options that Google offers. Of course you can remove languages you don't like and it'll simply work. You can try it here !! I've put it in the sideBar... have a look !! Alsalam Alikom wa ra7mat Allah wa barakatoh

Developers to rewrite the history and have their own country...

Alsalam alikom wa ra7mat Allah w abarakatoh, When a friend of mine told me that there r some guys thought to buy an island (originally owned by England) to build their own country and put their own rules and such.. I was just amused and wanted to read more.. and here is a summary of the story : AFCI is a group of people who don't like the current Copyright laws (and who does!!) so they decided to search for a new country where they can put their own laws of copyright, Imagine u can live in the IT World for FREEE... imagine a country where ur president (maybe u will be the president one day) is a developer (a hacker maybe !!) maybe u will have to write some lines of code to pay for ur car rental... or contribute in an open-source project to buy a better apartment.. There are a lot of interesting endless ideas that came to my mind... I really like the idea and I like that they have a Plan B in case they didn't manage to get the required money (about 500m British Pounds) they r pl

ACM Regional 2006 Contest Pictures

Alsalam alikom wa ra7mat Allah wa barakatoh I've uploaded some pictures from a collection, of about 700mb pics & videos, to my public Albums ACM 2006 Regional Contest Have a look. Alsalam alikom wa ra7mat Allah wa barkatoh

Common Developing mistakes.. How to avoid !!

Alsalam alikom wa ra7mat Allah wa barakatoh I've read a gr8 article in MSDN and I thought to share it... here r some quotes from it - Load other forms in the background and populate controls with data before using the Show method. - Use an off-screen bitmap. For an example, see How to: Draw Images Off-Screen . - Override the OnKeyDown , OnKeyPress , and OnKeyUp methods on controls instead of adding key event handlers. - Avoid using the ToString method of an enumeration because of the performance impact it incurs by searching metadata tables. - Strings are immutable, so a new String object is created every time you modify the string. Consider using a StringBuilder when constructing a string that will be modified often. - Use the ParseExact method for a DateTime if you know the exact format used for DateTime serialization. Otherwise, the DateTime parser will sequentially try to apply several culture-specific formats. - Whenever possible, specify the size of your collection,

Outsourcing...

Alsalam alikom wa ra7mat Allah wa barakatoh, Yesterday I started to put our projects online to let a wider range of people c them.. I'm not pretending that our projects are on a commercial level... But at least, when someone, trys to search google to learn, they may popup for him and he can benefit from them... Actually we didn't find any useful source-code when we were making those projects... maybe it's time to let others find some (hope to be) useful code.. I've started with 2 projects VisualPro our Visualization Package.. I've created a discussion group too in case anybody is interested to discuss any technique.. AlgorithmsVisualized a Framework to implement any graph algorithm for it.. You can find the links on the right bar too.. Hope nobody uses them for bad things... they r licenced anyway... That's it for now.. hope other projects come soon Alsalam alikom wa ra7mat Allah wa barakatoh