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Tor->VPN in TAILS to bypass tor-blocking

This post will describe how to route outgoing traffic in a python script running on TAILS first through Tor, then through a SOCKS proxy created with an ssh tunnel. This is helpful when you want to use the anonymizing capabilities of tor, but you need to access a website that explicitly blocks tor exit nodes (common with sites running CloudFlare on default settings).


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pycurl through Tor without leaking DNS lookups

This article describes the correct way to use pycurl over Tor, such that both DNS lookup data and HTTP(S) traffic is sent through Tor's SOCKS5 proxy.

If you google "pycurl tor", one of the first results is a stackoverflow post that describes how to configure pycurl using the pycurl.PROXYTYPE_SOCKS5 setting. Indeed, even the tutorial To Russia With Love on the Tor Project's Official Website describes how to pass pycurl through Tor using the pycurl.PROXYTYPE_SOCKS5 setting.

However, using pycurl.PROXYTYPE_SOCKS5 will leak DNS queries associated with your HTTP requests outside of the Tor network! Instead you should use pycurl.PROXYTYPE_SOCKS5_HOSTNAME.

The --socks5-hostname argument was added to libcurl v7.26.0. The pycurl.PROXYTYPE_SOCKS5_HOSTNAME argument wasn't added to pycurl until pycurl v7.19.5.1, which (at the time of writing) was less than 2 months ago!

This article will describe how to install pycurl v7.19.5.1 onto the latest version of TAILS at the time of writing, which is TAILS v1.2.3.


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Eavesdropping Analysis of PGP Metadata

This post attempts to answer the following question: If an evesdropper intercepts a message encrypted with gpg, how much information will they be able to extract from the message without a decryption key?

I will show the unencrypted metadata added to a GPG-encypted message, and I will present commands that can be used to extract this unencrypted metadata.


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Browsing without being tracked via Fingerprinting

Your browser aggrigates a *lot* of data about your computer, and it won't hesitate to provide all of this data to a nosy web site. In fact, if a website requests a large dataset of your computer's configuration, concatinates it together, and passes it through a hash function, the resulting hash can be farily unique.

This procedure can be done (and is done) on seperate websites to track users and their activity across multiple websites. If the same procedure [get data, concatenate, hash()] produces the same hash value when done on 2 seperate websites, the website can be fairly certain that you're the same user. This technique for tracking users is known as Browser Fingerprinting.

Just to get an idea of how effective this is, here's an excerpt from the above-linked article:

[The EFF] found that, over their study of around 1 million visits to their study website, 83.6% of the browsers seen had a unique fingerprint; among those with Flash or Java enabled, 94.2%. This does not include cookies!

You can test the uniqueness of your browser's "fingerprint" using this handy EFF tool.

There is a really great document descirbing techniques that could be used to prevent
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Custom Synapse Shortcuts

I've been using Synapse for a few months now. This software is invaluable to my experience on my PC because: # I can *quickly* do what I want to do without fighting with a big, hierarchaial menu # It doesn't require any huge dependencies (I use XFCE, so I don't want something that requires Gnome or KDE libraries)

Unfortunately, the documentation is non-existant. So when I wanted to be able to configure Synapse to execute a custom command when I typed a custom keyword, it took me a while to figure it out.

This post explains how to define custom commands in Synapse to execute custom commands in your terminal. For example, I'll show how to make "Google Drive" open a firefox window to https://drive.google.com


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Github

With each passing day, it's becoming more and more obvious that Internet users are transitioning to cloud-based storage. Between (1) My home workstation running Arch Linux, (2) my laptop dual-booting in Ubuntu Linux and Windows 7, (3) my netbook running eeebuntu, and (4), public-access PCs at my University, I need a way to open the latest version of our files from any geographic location on any OS.

A few years ago I built a multi-TB storage solution which hosted my personal, online Subversion repository. But power is expensive, so this box ended up getting turned off. In response, I fell into the bad habit of storing my source code merely as files on the cloud without version control.

Several years ago (assuming your file was small enough) this meant emailing an attachment. Or, more recently, uploading it to Google Docs. Then people started using DropBox. Finally, if you cared about the privacy of your data, you moved to Wuala.

But Wuala tends to corrupt my files as I'm editing them in gvim, so I started storing my files locally again--which rocked the boat and convinced me to finally get around to learning git. Git has always been on my to-try
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UCF Wifi in Ubuntu

This month (September 2011), UCF officially killed the "UCF" SSID to be replaced by "UCF_WPA" and "UCF_WPA2." Configuring Ubuntu Linux to connect to the UCF WPA2 network is neither trivial nor documented by UCF.

To aid other UCF Ubuntu users, I created a Wireless article on the unofficial UCF wiki. This includes links to the official UCF certificates and instructions on how to connect to the UCF_WPA2 network in Ubuntu.

Michael Altfield's gravatar

UCF Wifi Rant

While I frustratingly waited to connect to the UCF Wifi after a recent change to their system, I typed up the following email complaint to the UCF DoIT Manager. If *you* have also had issues with unstable/dropped connections, slow bandwidth, latency, or the inability to connect to the UCF Wifi, I urge you to also contact the UCF Department of Information Technology via:

cst@ucf.edu = General bob.yanckello@ucf.edu = Bob Yanckello (UCF Chief Technology Officer) lou.garcia@ucf.edu = Lou Garcia (UCF Network Manager [responsible for wireless services]) chrisv@mail.ucf.edu = Chris Vakhordjian (Information Security Office) tim.larson@ucf.edu = Tim Larson (ERP Consultant) jim.ennis@ucf.edu = Jim Ennis (Enterprise Systems & Operations) andy.hulsey@ucf.edu = Andy Hulsey (Telecommunications [includes Network Services]) aaron.streimish@ucf.edu = Aaron Streimish (Project Performance & Management Office)

Email below

While I understand the benefit of encrypted wireless communications, UCF's decision to require all student wireless clients to use WPA without preparing to sufficiently upgrade the wireless infrastructure has rendered the UCF Wifi *unusable*.

Allow me to provide a brief log of my Internet Experience this afternoon (2011-09-15).

12:02 - attempt to connect to WiFi - fail for 9 minutes 12:11 - connected 12:11 - google 'email ucf department of information technology' 12:12 - disconnected
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RegEx 2 DFA in Python

For my Discrete Mathematics II course at UCF (COT4210), I had to do some implementation with Finite State Machines. My favorite of our tasks (though the most difficult) was to convert a Regular Expression (RE) to an equivalent Deterministic Finite Automata (DFA). And since our professor let us use any language, I tried to branch out from Java & C (which are annoyingly overused in Academia). I decided to teach myself Python. And it turns out, it was a good choice too--considering it's wonderful built-in functionality for Lists, and the heart of this program is a huge 2D array defining the automata's transition function. Also, I miss scripting languages--especially when I'm writing a program as a learning experiment as opposed to trying to make it as efficient as possible.

So, without further Ado: here's my code. It reads a RE in postfix notation from input.txt. Two cautions about postfix REs:

You must explicitly state concatenation The Kleen Star is already a postfix operator in REs, so it doesn't really work to use a mathematical infix2postfix library, as it treats the kleen star like an infix multiplicative operator. I treat it as an operand and throw it directly into the
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My Search for The Best MP3 Player

I'm going on another cross-country cycling trip this summer, and I'm in the market for a good, solid MP3 player.

Disclaimer: I'm a software guy who likes my devices to be good quality and long lasting. I'm by no means an audiophile, hardware tech, or professional MP3 player reviewer. All of my research was done using Google, and the only MP3 player I've owned is the Sansa e260 v2.

Requirements

Note: These are my personal requirements. They effectively eliminated a *lot* of products in the MP3 market.

1. Rockbox Support

First and foremost, I need rockbox support. Rockbox is a must-have FOSS firmware for MP3 players with a fantastic feature list. You can buy an MP3 player with terrific hardware design, but your experience can be absolutely ruined by poorly designed firmware. My old Sansa e260 was this way, but once I installed rockbox, it was like the device was freed from a software prison. And, of course--another benefit of it being open source--you can completely customize the look+feel of your MP3 player with other user's custom rockbox themes.

Here is a list of MP3 players (targets) and their support status for the Rockbox firmware.

2. Rugged Components that
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