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Using QR codes for coding files and text

The other day I discovery how change the Guard node (Entry node) in Tor for the Tor daemon, just delete all the files in /var/lib/tor/. This is a bad thing to do, for more information search in Duckduckgo.

Today we will learn how to use QR codes for encoding files. Sometimes we use virtual machines that have no means to interact with the host machine. Maybe due to security concerns or you don't want to mess with config files and command line options. Or simply because you are only allowed to send pictures but no files.

Whatever is your reason, you must be truly desperate to use it as this method is only limited to 3000 characters.

I also tried with OCR software, but that was a pretty bad idea, the QR codes works just well.

Let's we suppose that we want to encode a text file as QR pictures, these are the steps. You should use the base64 command for non plain text files (base64 binary > file.txt)

Step 1. Install zbar where you will decode the text.

You can find it in Ubuntu as zbar-tools and is available in AUR as zbar-headless. In AUR you will also found the QT and GTK version.

I actually compiled it manually and disabled some features at compile time as we only will need the cli.

./configure --without-gtk --without-qt --disable-video

Step 2. Install qrencode

Install this in the place where you will generate the QR pictures. This application is available in the Debian/Ubuntu and Arch repos.

Step 3. Split the file

This step is need only if you need to split the file in several parts as the limit is about 3000 characters With the following command you can split a file by number lines.

split file -l number

You can count the total lines with the following command

wc -l file

Step 4. Create the QR

Execute the following command in the same directory where you split the file:

for p in {a..z} ; do ( cat xa$p | qrencode -o qr$p.png ) ; done

Step 5. Decode the QR codes

Before continue you have to take pictures to the qr codes or taking screenshots, and then rename the pictures with their original names. Then cd to the directory containing the qr pictures.

for p in qr*.png ; do ( zbarimg --raw $p | sed '$ {/^$/d};' ) > ${p%.*}.txt; done

Step 6. Concatenate the files

cat qr*.txt > file

This method works if the qr images are being saved in the target machine with the same name as the source machine.

Installing Conky in Qubes OS 4.0

Qubes Os Screenshot

This is a bad thing to do, but the easiest way to install Conky in Qubes OS is using the RPM packages of Fedora 24.

First you need to download the following packages:

  • giflib-4.1.6-15.fc24.x86_64
  • imlib2-1.4.9-1.fc25.x86_64
  • iw-4.1-2.fc24.x86_64
  • crda-3.18_2016.02.08-1.fc24.x86_64
  • wireless-tools-29-14.1.fc24.x86_64
  • tolua++-1.0.93-18.fc24.x86_64
  • conky-1.10.4-1.fc25.x86_64

Then install all them, they are in the installed order, the packages highlighted with bold letters are the main dependencies for installing conky

You can install all of them using

rpm -i *

Qubes Os is not for everyone.

When I first tried Qubes OS some months ago, it changed my view of security. Many people complains that is not very good for daily work, but I don't think that's have to be true.

I mean, I've using Slackware for some months, the more hard is something, the most creative you became. I'm impressed of myself due to my ability to solve problems.

I don't really know why I chose Slackware, the more I tried to explain, the more false looks for me. But I'm sure that I chose it because the DVD includes lots of useful utilities and windows managers.

With regards with Qubes OS, if you get used to security, then Qubes OS will be a good fit for you. But I don't know what to say, my way of understanding the world is incomprehensible for everyone. In my mind things really complex are too simple for me. By the other hand, frequently complex activities or plans of mine are empty of meaning.

But I think that there are simple things I liked about it: The main filesystem in the Virtual Machines are keep intact and changes are lost in each reboot, I really like how it it's isolated because there doesn't remain the system logs.
You can easy deleted a virtual machine and so easily control the metadata of your activity.

Actually I'm a bit obsessed in controlling the information because everything generates metadata. It's an obsessive-compulsive idea, but maybe I'm not wrong because the experts in security says to treat the information the same as radioactive waste.

Also I do like protecting the information, maybe I just care about information as few people in the world. I also love sharing information.

Does really people has an appropriate computer?

I would say that you should have at least 100G free for Qubes OS, 8G of RAM and a fast SSD. I use a raid with 3 hard disk and the start up process takes some time. I only suspend the computer instead of shutting down it in order to avoid stressing so much my hard disks. Qubes OS is making to suffer my hard disk. You can do many optimizations in the hard disk increasing the cache and delaying the writes.

I highly recommend a PSU because the last time my Qubes Os were ruined with an power outage in my house. The disposables machines uses lots of IO resources. I may say that the Anaconda installer is kind of tricky. It contains little bugs, so you will have to get dirty in the terminal.

Does really people think the more complexity, the more prone to failure?

Actually my Qubes OS system is working with 70 partitions of many kinds, loop devices, device mapper, and traditional, half of them mine, the other half are dependencies for Qubes OS. By the way, I only use 4 workplaces.

So don't be silly and do not create so much workplaces. Sometimes people are afraid of creating a third partition when right here we have tens of partitions.

Does really people know how to use Tor?

I was thinking that we don't need two Whonix installations since we can improvise the Whonix gateway with the Fedora template using a transparent Tor proxy. It's only a matter to modify the tor browser typing about:config and specifying the IP of the router plus the open port 9050. Finally disabling the extension that Start Tor. It's important to do in this way and not enabling the transparent proxy in Tor Browser since the transparent proxy cannot change the IP in each tab.

Does people really realize that more Templates means more updates?

Keep it minimalistic, because installing Qubes OS is like installing 5 operative systems, so it will increase the complexity of maintaining.

Does people really know about Fedora and Debian?

This question is relevant because some people rarely uses Linux, or more important, you may use Linux but don't know about both RPM or Deb package system. The RPM package system is special and sometimes needs kind of maintenance in matters such as expired package cache, or maybe the updates systems is locked.

Another considerations:

Moving files to dom0 isn't the most easy, but you can get used to the command to do it.

Android. How to share files directly with WI-FI

Bluetooth can be useful for sharing files, however, it is pretty slow and not all the laptops and portable devices support it. Here you will learn how to share files via WIFI to any device, and the best is that you won't need to carry a USB cable.

There are many apps in the Play Store that does the trick, but contains adds and are not open source , such as Wi-Fi Direct or Superbeam.

I hope you find this method more transparent and simple.

First you will need to enable the Portable Wi-Fi Hostpot in your cellphone, there you will create a Wi-Fi network with a custom name and password.

For more details visit the following link:


Then connect to that Wi-Fi network with the other device. In this way both devices are (almost) ready to share files.

Finally install and run the FTP server application available in both Play Store and F-droid. It will show you an ip like , type that ip in a web browser from your laptop (the device connected to the Hotspot) , and there you can browse and download the files of your Android device.

Do not forget to disable the Hotspot in the same way that Data mobile is disabled (in the android settings drop-down menu)

Note: You can skip the first step if both devices are connected in the same local network, in that case you only need to use the FTP server application. However, notice that the transfer speed will be slower.

New appearance

I intended to change the theme of pinkhat.rpm.li as the first picture, also I tried this:

This was the original:

It's difficult to choose between them, all of these 3 has their own charm, the first is cute , the second is modern, unique and vivid, and the third is simple, practical and beautiful.

I love so much all of these, but I will choose the first because I feel it's the real essence of my site.

Here is a snapshot of how my site looks in the end Snaptshot (January 16)