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URI Design and Ownership - IETF Draft

2014 May 21, 2:06

URI Design & Ownership - On the issues with and alternatives to requiring well known filenames and extensions in URIs. You must love the draft’s URI.

PermalinkCommentstechnical uri

GitHub - asciimoo/drawille

2014 May 21, 1:54

drawille - Drawing in terminal with unicode braille characters

Uses the Unicode Braille characters to make advanced (non-)ASCII art.

PermalinkCommentshumor technical art

http://tools.ietf.org/html/draft-wkumari-not-a-draft-00

2014 Apr 14, 7:22
tp://tools.ietf.org/html/draft-wkumari-not-a-draft-00
PermalinkCommentshumor technical ietf atlanteans

Keep Talking and Nobody Explodes. Co-op Oculus Rift + Razer Hydra

2014 Jan 28, 6:17PermalinkCommentshumor game videogame bomb

thefrogman: Poorly Drawn Lines by Reza...

2013 Oct 15, 7:47


thefrogman:

Poorly Drawn Lines by Reza Farazmand
[website | tumblr | twitter | facebook]

PermalinkCommentshumor comic robot

Video memory offer and reclaim (Windows Drivers)

2013 Sep 18, 9:41PermalinkCommentstechnical windows driver memory offer-reclaim

Kartlytics (by Deirdré Straughan)

2013 Aug 9, 7:53


Kartlytics (by Deirdré Straughan)

PermalinkCommentshumor technical Mario-kart video-game manta map-reduce cloud-computing

C++ constructor member initializers run in member declaration order

2013 Jul 18, 3:29

TL;DR: Keep your C++ class member declaration order the same as your constructor member initializers order.

C++ guarantees that the member initializers in a constructor are called in order. However the order in which they are called is the order in which the associated members are declared in the class, not the order in which they appear in the member initializer list. For instance, take the following code. I would have thought it would print "three, one, two", but in fact it prints, "one, two, three".

   
#include "stdafx.h"
#include

class PrintSomething {
public:
PrintSomething(const wchar_t *name) { std::wcout << name << std::endl; }
};

class NoteOrder {
public:
// This order doesn't matter.
NoteOrder() : three(L"three"), one(L"one"), two(L"two") { }

PrintSomething one;
PrintSomething two;
PrintSomething three;
};

int wmain(const int argc, const wchar_t* argv[])
{
NoteOrder note; // Prints one, two, three, not three, one, two!
return 0;
}
PermalinkCommentsc++ development programming technical

Words with Hints Windows 8 App Development Notes

2013 Jul 4, 1:00

My second completed app for the Windows Store was Words with Hints a companion to Words with Friends or other Scrabble like games that gives you *ahem* hints. You provide your tiles and optionally letters placed in a line on the board and Words with Hints gives you word options.

I wrote this the first time by building a regular expression to check against my dictionary of words which made for a slow app on the Surface. In subsequent release of the app I now spawn four web workers (one for each of the Surface's cores) each with its own fourth of my dictionary. Each fourth of the dictionary is a trie which makes it easy for me to discard whole chunks of possible combinations of Scrabble letters as I walk the tree of possibilities.

The dictionaries are large and takes a noticeable amount of time to load on the Surface. The best performing mechanism I found to load them is as JavaScript source files that simply define their portion of the dictionary on the global object and synchronously (only on the worker so not blocking the UI thread). Putting them into .js files means they take advantage of bytecode caching making them load faster. However because the data is mostly strings and not code there is a dramatic size increase when the app is installed. The total size of the four dictionary .js files is about 44Mb. The bytecode cache for the dictionary files is about double that 88Mb meaning the dictionary plus the bytecode cache is 132Mb.

To handle the bother of postMessage communication and web workers this was the first app in which I used my promise MessagePort project which I'll discuss more in the future.

This is the first app in which I used the Microsoft Ad SDK. It was difficult to find the install for the SDK and difficult to use their website, but once setup, the Ad SDK was easy to import into VS and easy to use in my app.

PermalinkCommentsdevelopment technical windows windows-store words-with-hints

Audi Piloted Driving at CES 2013 (by AudiofAmerica)

2013 Jun 21, 9:30


Audi Piloted Driving at CES 2013 (by AudiofAmerica)

PermalinkCommentscar video self-driving

Super Mario World “Completed” in Under 3 Minutes by Corrupting the RAM | minimaxir

2013 Apr 3, 4:46

This is essentially an AV exploit against Super Mario World that results in running the end game code. Watch the video. “…there’s a glitch that’s been known for a while, where Yoshi can end up in the “I have an item in my mouth” state, but not actually have an item in his mouth. When he spits out this nothingness, the game crashes. …That address did not contain code, and so the system crashed. But wait a second. What if, by some sheer coincidence, that address did contain code? The specific address dropped him in somewhere amongst various data for the game’s internal random number generator, and the random number generator can be manipulated in a TAS. Could the game be coerced into running arbitrary code?…”

PermalinkCommentshumor game hack mario

The Making of Pulp Fiction: Quentin Tarantino’s and the Cast’s Retelling | Vanity Fair

2013 Feb 28, 3:03

The first independent film to gross more than $200 million, Pulp Fiction was a shot of adrenaline to Hollywood’s heart, reviving John Travolta’s career, making stars of Samuel L. Jackson and Uma Thurman, and turning Bob and Harvey Weinstein into giants. How did Quentin Tarantino, a high-school dropout and former video-store clerk, change the face of modern cinema? Mark Seal takes the director, his producers, and his cast back in time, to 1993.

PermalinkCommentsarticle movie film interview pulp-fiction

draft-ietf-websec-framework-reqs-00 - Web Security Framework: Problem Statement and Requirements

2013 Feb 20, 2:48

Web Security Framework: Problem Statement and Requirements

PermalinkCommentstechnical rfc security web html

How To Screen Capture on the Microsoft Surface RT - Surface...

2013 Jan 7, 11:44


How To Screen Capture on the Microsoft Surface RT - Surface Geeks Surface Geeks

tl;dr: hold windows logo on the surface (not keyboard) and press volume down button on the surface

PermalinkCommentstechnical surface windows

Stripe CTF - Level 8

2012 Dec 7, 2:07
Level 8 of the Stripe CTF is a password server that returns success: true if and only if the password provided matches the password stored directly via a RESTful API and optionally indirectly via a callback URI. The solution is side channel attack like a timing attack but with ports instead of time.

(I found this in my drafts folder and had intended to post a while ago.)

Code

    def nextServerCallback(self, data):
parsed_data = json.loads(data)
# Chunk was wrong!
if not parsed_data['success']:
# Defend against timing attacks
remaining_time = self.expectedRemainingTime()
self.log_info('Going to wait %s seconds before responding' %
remaining_time)
reactor.callLater(remaining_time, self.sendResult, False)
return

self.checkNext()

Issue

The password server breaks the target password into four pieces and stores each on a different server. When a password request is sent to the main server it makes requests to the sub-servers for each part of the password request. It does this in series and if any part fails, then it stops midway through. Password requests may also be made with corresponding URI callbacks and after the server decides on the password makes an HTTP request on the provided URI callbacks saying if the password was success: true or false.
A timing attack looks at how long it took for a password to be rejected and longer times could mean a longer prefix of the password was correct allowing for a directed brute force attack. Timing attacks are prevented in this case by code on the password server that attempts to wait the same amount of time, even if the first sub-server responds with false. However, the server uses sequential outgoing port numbers shared between the requests to the sub-servers and the callback URIs. Accordingly, we can examine the port numbers on our callback URIs to direct a brute force attack.
If the password provided is totally incorrect then the password server will contact one sub-server and then your callback URI. So if you see the remote server's port number go up by two when requesting your callback URI, you know the password is totally incorrect. If by three then you know the first fourth of the password is correct and the rest is incorrect. If by four then two fourths of the password is correct. If by five then four sub-servers were contacted so you need to rely on the actual content of the callback URI request of 'success: true' or 'false' since you can't tell from the port change if the password was totally correct or not.
The trick in the real world is false positives. The port numbers are sequential over the system, so if the password server is the only thing making outgoing requests then its port numbers will also be sequential, however other things on the system can interrupt this. This means that the password server could contact three sub-servers and normally you'd see the port number increase by four, but really it could increase by four or more because of other things running on the system. To counteract this I ran in cycles: brute forcing the first fourth of the password and removing any entry that gets a two port increase and keeping all others. Eventually I could remove all but the correct first fourth of the password. And so on for the next parts of the password.
I wrote my app to brute force this in Python. This was my first time writing Python code so it is not pretty.
PermalinkCommentsbrute-force password python side-channel technical web

Windows Remote Desktop via Internet

2012 Dec 7, 2:04
To setup my home Windows dev box to be accessible from outside I followed two main steps:
Last time I had to do this there was a service named dynamicdns.org which seems to still exist but no longer appears to be free. Instead I used dnsdynamic.org which is free and has a web API as well as links to and instructions for setting up native tools to dynamically update my IP address.
PermalinkComments

laughingsquid: Solitaire.exe, A Real Deck of Cards Inspired by...

2012 Nov 19, 4:56


laughingsquid:

Solitaire.exe, A Real Deck of Cards Inspired by the Windows 98 Solitaire PC Game

PermalinkCommentshumor solitare game cards windows

Why aren’t my kids hyper after binging on sugar?

2012 Oct 1, 8:23

“A particularly troublesome finding was that for some children, if they were told that sugar would make them hyper, then they actually would become hyper after thinking that they had eaten sugar.”

PermalinkCommentsscience sugar parent

Ben Goldacre’s TED talk on publication bias, drug...

2012 Sep 28, 3:55


drug companies hiding the results of clinical trials.

(via I did a new talk at TED, on drug companies and hidden data.)

PermalinkCommentsscience video ted

Alexandria 2.0: One Millionaire's Quest to Build the Biggest Library on Earth | Threat Level | Wired.com

2012 Aug 21, 7:00

Brief history and scope of the Internet Archive.

PermalinkCommentsinternet-archive history
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