By stating that ...
read moreHow to maximize X (success, happiness, skill, or whatever) in your life:
Change the following settings in Firefox's about:config to enable TLS v1.1.
Steps
I had to uninstall compiz today, and I absolutely can't live without being able to switch virtual desktops (also known as workspaces) with the buttons on the side of my mouse. Here's how you do it:
First, install xbindkeys and xdotool:
apt-get install xbindkeys xdotool
Then create a ...
read moreThis is a simple Ruby script that helps you memorize a password by making you type it over and over again. It first breaks the password into chunks of 4 characters, helps you to memorize each chunk, then every consecutive pair of chunks, then every consecutive triple... and so on ...
read moreThis is the easiest way I have found to typeset premise and conclusion style arguments in LaTeX. First, add this to your preamble:
\usepackage{amssymb}
Then use something like this to typeset the argument:
\begin{itemize} \item[1.] Premise One. \item[2.] Premise Two. \item[3.] Premise Three. \item[$\therefore ...read more
Inspired by Richard Dawkins' weasel program, this is a genetic algorithm, written in Ruby, to evolve the same "METHINKS IT IS LIKE A WEASEL" string. It's really fun to experiment with changing the probability constants (mutation, reproduction) and the algorithm in Evolver#advance, which advances the population of strings ...
read moreSteps to reset a Windows account password given physical access to the box:
Here's a Ruby script to experiment with correlations that may be useful in developing a genetic (evolutionary) algorithm for factoring the product of two primes. The comments explain it:
#!/usr/bin/env ruby # Let C = F1 * F2, where F1 and F2 are primes. # # This script gives a visual aid ...read more
EDIT: What I propose here doesn't actually fix it, it still fails when there's a greater-than sign inside an if statement. I have spent over 8 hours trying to get this to work and that is too much, so I am giving up. If you find a solution ...
read moreHere's how to do encrypted automated backups without having to store the password in the backup script. The script should be self-explanatory (after all, it is 50 lines of comments for just one real line of code).
#!/bin/bash
# File name: backup.sh
# This script automates the process of ...
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With this post I will try to show how, in a theoretical scenario, deliberately weakening the collision resistance of a password hash function can increase security. This is by no means a formal proof.
Suppose Alice has an account on two computer systems X and Y. She uses the same ...
read moreYou have a list of processes and a list of resources, and for each process you have:
When a process makes a request for a resource, you only allocate the ...
read moreI had to do some Gaussian elimination for an assignment. So here's Gaussian elimination in Ruby:
# Performs an in-place Gaussian elimination on an NxN matrix 'matrix' (2D array # of Numeric objects) and an N-element vector 'vector.' (array of N Numerics). def gaussianElimination(matrix, vector) 0.upto(matrix.length - 2 ...read more
So there's this video of a voting machine that selects Romney when you try to click on Obama.
To someone who has had some experience with touch screen technology, it looks like the touch system is just out of sync with the UI, which could be fixed by re-calibrating ...
read moreToday, I came across an article on password cracking. In the comment section I saw someone had posted (presumably right after they just read about salting) the following reply:
My solution: don't store hashes as a single SHA1 or MD5 result ... combine it for further obfuscation. A hash is ...read more
All of the x86 stack diagrams I could find are either cluttered with too much information, can't be read from a distance, or put the high address on top (I'm sure there are people who prefer that but... I'm not one of them). So I made my ...
read moreSuppose a system uses a constant internal initialization vector to encrypt/decrypt data in CBC mode, and you'd like to know what it is. If you can make the system decrypt chosen ciphertexts, this is how you do it:
def with( obj ) yield obj end with Math do |m| puts m.exp( 1 ) puts m.exp( 2 ) puts m.exp( 3 ) end # Deeply nested modules module Foo module Bar module Baz A_CONSTANT = 3 def self.aMethod( x ) x * A_CONSTANT + A_CONSTANT end end module Biz def self.anotherMethod( x ) "hello ...read more
If mplayer is giving you an error like the following...
AO: [pulse] Init failed: Connection refused Failed to initialize audio driver 'pulse' [AO_ALSA] Unable to set hw-parameters: Invalid argument Failed to initialize audio driver 'alsa' [AO SDL] Samplerate: 44100Hz Channels: Stereo Format floatle [AO SDL] using aalib audio driver. [AO ...read more
Is your pipe/backslash key not typing pipes and backslashes? Is it typing less-than and greater-than symbols? If so, add...
key <LSGT> { [ backslash, bar, backslash, bar] };
..to /usr/share/X11/xkb/symbols/us in the kxb_symbols "basic" section.
This seems to be a problem with ASUS laptops, I've seen ...
read moreIf you're a PHP developer that's starting to fall in love with ruby (like me), you'll want to know how to write "PHP-style" web applications in ruby, for small web apps that don't need the complexity of Ruby on Rails. You want:
Use the following code to escape user-supplied input before inserting it into a JavaScript string literal.
<?php function js_string_escape($data) { $safe = ""; for($i = 0; $i < strlen($data); $i++) { if(ctype_alnum($data[$i])) $safe .= $data[$i]; else $safe .= sprintf("\\x%02X", ord($data[$i])); } return $safe; }
Example:
<script> var foo = "<?php ...read more
The wmctrl program allows you to programatically bring a running application to the foreground on Linux. It works even with compiz enabled, and will switch to the virtual desktop that the application is running in before bringing it to the foreground. This makes it a perfect utility for mapping keyboard ...
read moreIf you use Truecrypt on GNU/Linux, you will want to stop mlocate (the locate command) from automatically indexing your files and compromising your privacy.
To do so on Debian Squeeze:
apt-get remove mlocate rm /etc/cron.daily/mlocate
The database files are stored in:
/var/lib/mlocate/
Delete them ...
read moreRuby is an awesome programming language. Its metaprogramming capabilities make it easy to turn the interactive ruby interpreter (irb) into an awesome desktop calculator. To do so, we can make irb execute a ruby script, containing some calculator extensions before it starts, with the following command:
irb -r /path/to ...read more
This week, LinkedIn, eHarmony, and last.fm have all confirmed that their password hash databases have been breached. In all three cases, passwords were stored as an unsalted hash. I've already reported the results of cracking LinkedIn's password hashes with CrackStation, now it's eHarmony's turn.
eHarmony ...
read moreLinkedIn's user database has been breached. The passwords were hashed with SHA1, but salt was not used. 6 million of them have been published to the internet. You can download them via torrent or via HTTP from defuse.ca's mirror. 3.5 million of them have had their ...
read moreToday a member of GRC's Newsgroups posed a question about security through obscurity:
read moreIt seems to me that ALL digital security is EXACTLY "security through obscurity". Take, for example, AES... It isn't that the possible range of keys is unknown, it is just a cleverly hidden needle in ...
Just having fun...
This evaluates to the string "?".
??????????????:????????:??:??:??:??:?????:?? # => "?"
$i=0;[$c="[$s=['p '],[$s<<[*1?3??'+?<+?3:?y:?]],$s+=[?b],$s|=[*?y+?'],$s[2,0]=5??r+?u:?$],($i+=1)<30?eval($s.join<<?;<<$c):nil]",eval($c)]
"<3ruby" "<3ruby" "<3ruby" "<3ruby" "<3ruby" "<3ruby" "<3ruby ...
Here's a recursive-backtracking ASCII maze solver I wrote to practice ruby. The o's are the solution.
$ ruby maze.rb maze.txt ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ++++oooooooo ++++++++++++++++++++++ ++++++++++++++++++++++++ ++++ ++++++ +oooo++ +++o++++++++++++++++++++++++ ++++ +++++++++++++++++++ +++ +++++++ ++++++ ++++ ++ oo+++++++++++++++++++ ++++ ++++ +++ +++ +++++++ ++++++ ++++ ++ ++o++++++++ooooooo+++++ ++++ ++++ +++++++++++++++++++ +++ ++++++ ++ +++++o++++++++o+++++o+++++ ++++ ++++++++++++++ ++++++++ +++++++++ ++++++++++o++++++++o+++++o+++++ +++++ ++++++++ +++oooooooooooooo++++++ +++++++++ ++++++++++o+oooooooo+++++ooooooo+++++ ++++++++ +++o++++++++ +++o++++++ +++++++++ ++++++++++ooo++++++++++++ +++++o+++++ +++++++++ o++++++++++++o++++++ +++++++++ +++++++++++++++++++++++++ o++++++++++++++++++o ++++++o +++++++++ +++++++ +++++++++++++++++++++++o ...
We know that it's possible to come up with a password that no computer on earth can crack. Use true random data to generate a sequence of 20 characters from the full ASCII printable set, spend an hour memorizing, and you're good. We also know that most people ...
read moreHere are some of my favorite .vimrc lines.
Save quickly from any mode by pressing CTRL+:
imap <C-\> <Esc>:w<Cr> map <C-\> <Esc>:w<Cr>
Make indenting and de-indenting in visual mode preserve the selection:
vnoremap > ><CR>gv vnoremap < <<CR>gv
Quick case insensitive search with double slash or ...
read moreThe following is a simple and easy way to get clipboard sharing with Vim working between two Linux installations (specifically a desktop and remote server).
First install xclip on both your local machine and the server:
apt-get install xclip
Installing xclip will bring along some dependencies like x11-common, but don ...
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