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Horror Stories from Digiland

On May 2019 we did a presentation at University of Nicosia about digital rights and horror stories regarding their violations. We talked about ways of how technology can be used against us, and about actions and tools we can use to protect ourselves.

You can find the presentation material here:

Horror Stories from Digiland

Here you can find some references that help in the creation of the presentation. This is a shorter version of an earlier presentation I did in greek so the references may not match exactly to this one.

ECHELON

Trailblazer

Sony Rootkit

Lower Merion High School

Afgan War Logs

PRISM

The Fappening

No cloud

Ashley Maddison

VW Scandal

Vault 7

Dropbox

Tesla Cars

Mobile Telephony

Truecaller

Smart TVs

Facebook

Target

Apple

Microsoft

Cabridge Analytica

Free-Basics

Backdoors – Malware

HTTPS Interception

Brain decoding – fMRI

Political Nightmares

Net Neutrality

So why should I care?

Protect yourself

Alternative social media

Protections in Telephony

Protection in Email

Other Solutions

GDPR

Digital Rights Organizations

Rysiek\’s Law

Digital Rights in Cyprus

Digital Rights

Orwell vs Huxley

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Building opendmarc for Debian Jessie

I have been using Skelleton‘s guide1 to setup opendmarc on some mail server I am building.

My problem is the version of opendmarc that comes with Debian is 1.3.0 and this version has a bug2 which fails to honor the IgnoreAuthenticatedClients directive.

This is an attempt to build3 the newest version, 1.3.1, for Debian jessie.

Prepare the environment

  • Install all necessary packages: 
    $ sudo apt -y install pbuilder debootstrap devscripts packaging-dev debian-keyring
  • Prepare a Debian jessie build environment: 
    $ sudo pbuilder create --debootstrapopts --variant=buildd --mirror http://ftp.us.debian.org/debian/ --distribution jessie --architecture amd64 --components main --debbuildopts -mJohn Doe \<john .doe@example.net\>

Prepare the Debian environment for opendmarc 1.3.1

  • Download and extract the package: 
    $ wget http://downloads.sourceforge.net/project/opendmarc/opendmarc-1.3.1.tar.gz
$ tar xvzf opendmarc-1.3.1.tar.gz
$ cd opendmarc-1.3.1/
  • Prepare for Debian packaging: 
    $ DEBFULLNAME="John Doe" DEBEMAIL="john.doe@example.net" dh_make -s -y --createorig
    • Rename the debian folder: 
      $ mv debian debian.orig
  • Shamelessly copy *debian/** from the original: 
    $ cd /tmp/
$ apt-get source opendmarc
$ cd opendmarc-1.3.1+dfsg/
$ cp -a debian/ ~/opendmarc-1.3.1
  • Optional steps:
    • Change the Author name to yours in debian/control

    • Restore the debian/changelog file:

      $ cp debian.orig/changelog debian/

    • Get rid of the debian.orig folder: 
      $ mv debian.orig/ ..
    • Edit the debian/changelog file with dch -e: 
      opendmarc (1.3.1-1) unstable; urgency=medium<br />
  * Initial release: To fix the IgnoreAuthenticatedClients issue:
    http://www.trusteddomain.org/pipermail/opendmarc-users/2016-April/000636.html
 -- John Doe </john><john .doe@example.net>  Fri, 29 Apr 2016 13:43:22 +0300

Build opendmarc 1.3.1

  • Run pdebuild: 
    $ pdebuild
  • You cab find the resultant debs under /var/cache/pbuilder/result/: 
    $ ls -la /var/cache/pbuilder/result/
total 868
drwxr-xr-x 2 root      root        4096 Απρ  29 13:54 .
drwxr-xr-x 8 root      root        4096 Απρ  29 12:56 ..
-rw-r--r-- 1 theodotos theodotos  38534 Απρ  29 13:54 libopendmarc2_1.3.1-1_amd64.deb
-rw-r--r-- 1 theodotos theodotos  64210 Απρ  29 13:54 libopendmarc-dev_1.3.1-1_amd64.deb
-rw-r--r-- 1 theodotos theodotos   2348 Απρ  29 13:54 opendmarc_1.3.1-1_amd64.changes
-rw-r--r-- 1 theodotos theodotos  75890 Απρ  29 13:54 opendmarc_1.3.1-1_amd64.deb
-rw-rw-r-- 1 theodotos theodotos    846 Απρ  29 13:54 opendmarc_1.3.1-1.dsc
-rw-r--r-- 1 theodotos theodotos 663859 Απρ  29 13:54 opendmarc_1.3.1-1.tar.gz
-rw-r--r-- 1 theodotos theodotos  17136 Απρ  29 13:54 rddmarc_1.3.1-1_all.deb

You can now copy the debs over your mail server and test them.

Update: I did this before I had discovered that opendmarc 1.3.1 is in Debian jessie backports4. But an interesting drill nevertheless.

References

  1. https://www.skelleton.net/2015/03/21/how-to-eliminate-spam-and-protect-your-name-with-dmarc/ ↩︎
  2. http://www.trusteddomain.org/pipermail/opendmarc-users/2016-April/000636.html ↩︎
  3. http://www.theo-andreou.org/?p=1145 ↩︎
  4. http://www.trusteddomain.org/pipermail/opendmarc-users/2016-April/000641.html</john> ↩︎
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Installing a Simple ORCID Authentication Node

These are the instructions for installing an ORCID1 authentication node. We will be using the simple-orcid-auth-node2 developed by the ORCID organization.

Assumptions

  • An Ubuntu 16.04 server machine but works on 14.04x with some minor changes.
  • A FQDN, let’s say orcid.example.com.
  • Server IP is 10.2.2.2 in our case.
  • Create an orcid user: sudo useradd -r -m -d /var/www/html/orcid orcid.
  • For Ubuntu 14.04 it is better to use /var/www/orcid instead of /var/www/html/orcid.
  • Also use service servicename restart on 14.04.x instead of systemctl restart service.

Installing simple-orcid-auth-node

  • Install necessary packages (as a privileged user): 
    $ sudo apt -y install nginx nodejs npm

    NOTE: If you are using Ubuntu 14.04.x do not install the node package. This package is completely unrelated with nodejs.__3

  • Download and extract simple-orcid-auth-node (as the orcid user):

    sudo su - orcid
wget https://github.com/rcpeters/simple-orcid-auth-node/archive/master.tar.gz
tar xvzf master.tar.gz

  • Install the application: 
    $ cd simple-orcid-auth-node-master/
$ npm install
  • Test run the application (as the orcid user): 
    $ nodejs client-app.js
server started on 8000

    Looks OK. Now point your Hit CTRL^C and move on.

    NOTE: If you prefer using the legacy node client-app.js invocation, you need to install the nodejs-legacy package as well.

Setting ORCID as an autostart service

  • Autostart using systemd4 (Ubuntu 16.04):

    • Create the /etc/systemd/system/orcid.service service definition (as the root user): 
      $ cat > /etc/systemd/system/orcid.service < < EOF
[Service]
ExecStart=/usr/bin/nodejs /var/www/html/orcid/simple-orcid-auth-node-master/client-app.js
WorkingDirectory=/var/www/html/orcid/simple-orcid-auth-node-master
Restart=always
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=orcid
User=orcid
Group=orcid
Environment=NODE_ENV=production
[Install]
WantedBy=multi-user.target
EOF
    • Reload systemd and start the service: 
      $ sudo systemctl daemon-reload
$ sudo systemctl start orcid.service
    • Verify that the service is started: 
      $ sudo systemctl status orcid.service
● orcid.service
Loaded: loaded (/etc/systemd/system/orcid.service; disabled; vendor preset: enabled)
Active: active (running) since Wed 2016-04-27 09:00:16 UTC; 37s ago
Main PID: 11141 (nodejs)
Tasks: 5 (limit: 512)
Memory: 24.1M
CPU: 268ms
CGroup: /system.slice/orcid.service
   └─11141 /usr/bin/nodejs /var/www/html/orcid/simple-orcid-auth-node-master/client-app.js
Apr 27 09:00:16 orcid systemd[1]: Started orcid.service.
Apr 27 09:00:16 orcid orcid[11141]: server started on 8000
  • Autostart using sysv-init (Ubuntu 14.04.x):
    • Prepare a sysv-init startup script or use mine for convinience: 
      $ cd /etc/init.d
$ wget https://raw.githubusercontent.com/theodotos/arena/master/orcid
$ chmod +x orcid
$ update-rc.d orcid enable
$ update-rc.d orcid defaults

    Now orcid should be able to autostart after a reboot.

Setting up nginx

  • Prepare this configuration:

    $ cat > /etc/nginx/sites-available/orcid < < EOF
server {
    listen 80;
    listen [::]:80 ipv6only=on;
    server_name orcid.example.com;
    access_log  /var/log/nginx/orcid.access.log;
    error_log /var/log/nginx/orcid.error.log;
    location / {
        proxy_pass http://localhost:8000/;
        proxy_set_header Host \$host;
        proxy_set_header X-Forwarded-For \$proxy_add_x_forwarded_for;
    }
}
EOF

  • Enable the orcid site: 
    $ cd /etc/nginx/sites-enabled/
$ sudo ln -s /etc/nginx/sites-available/orcid
  • Uncomment the following line in /etc/nginx/nginx.conf5: 
        server_names_hash_bucket_size 64;
  • Restart nginx: 
    $ sudo systemctl restart nginx.service
  • Verify nginx with sudo systemctl status nginx.service

Now you can visit the http://orcid.example.com site and test your setup

Going to production

The default simple-orcid-auth-node is using the sandbox ORCID service which is ideal for testing. This is how the configuration file (helpers/config.js) looks like:

module.exports = config = {
  // Config for OAuth2 
  CLIENT_ID: 'APP-O9TUKAPVLALU1SOJ',
  CLIENT_SECRET: '0eafb938-020e-45a6-a148-3c222171d9d8',
  AUTHORIZE_URI: 'https://sandbox.orcid.org/oauth/authorize',
  TOKEN_EXCHANGE_URI: 'https://api.sandbox.orcid.org/oauth/token',
  CODE_CALLBACK_URI: 'http://localhost:8000/authorization-code-callback',
  // General server config
  PORT: '8000',
  SERVER_IP: '127.0.0.1',
}
...

This setup will not work in production. You have to modify the CLIENT_ID and CLIENT_SECRET variables with your own credentials and change the AUTHORIZE_URI and TOKEN_EXCHANGE_URI to point to the production ORCID services:

module.exports = config = {
  // Config for OAuth2 
  CLIENT_ID: 'APP-HSGSHJS335353GSGSG',
  CLIENT_SECRET: '56d4eb21-6622-8483-3422-f53f3fs53sfs35f',
  AUTHORIZE_URI: 'https://orcid.org/oauth/authorize',
  TOKEN_EXCHANGE_URI: 'https://api.orcid.org/oauth/token',
  CODE_CALLBACK_URI: 'http://localhost:8000/authorization-code-callback',
  // General server config
  PORT: '8000',
  SERVER_IP: '127.0.0.1',
}
...

Restart nginx and orcid when done:

$ sudo systemctl restart nginx.service orcid.service

References

  1. https://en.wikipedia.org/wiki/ORCID ↩︎
  2. https://github.com/ORCID/simple-orcid-auth-node ↩︎
  3. https://github.com/ORCID/simple-orcid-auth-node/issues/3 ↩︎
  4. https://www.digitalocean.com/community/tutorials/how-to-deploy-node-js-applications-using-systemd-and-nginx ↩︎
  5. http://charles.lescampeurs.org/2008/11/14/fix-nginx-increase-server_names_hash_bucket_size</service> ↩︎
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Upgrade or Reload OpenElec on an XstreamTec HTPC media player

This guide describes how to upgrade your XstreamTec HTPC appliance from XBMC to KODI or re-install the system, in case of system corruption.

XstreamTec does not appear to have an official website but I have contacted them via Amazon and they promptly replied with instructions.

Prerequisities

  • An XstreamTec HTPC media player.
  • A Linux system with an SD card slot.
  • A Windows PC or VM (optional).
  • An empty SD card (4GB minimum).

Install the recovery firmware

  1. Download the android recovery sd card image (use Google Chrome or Chromium):

    https://mega.co.nz/#!wExHTJgC!XPuoFyhF_S-roTEhsMhQ8BLrfH4R5tXhp2jwaLF_o1M

  • Convert the image to raw format:

    If you extract the downloaded file (MATRICOM_MX2_115_FULL_AUG_09_2013.rar) you will get the image file (MATRICOM_MX2_115_FULL_AUG_09_2013.imgc). Alas this file has a peculiar format (.imgc) which is some kind of compressed raw image. I couldn’t figure out how to convert this to a raw (suitable for dd) image on Linux. To convert this to raw you need a Windows only utility called HDDRawCopy. So you will need a Windows system (WINE does not work for this) and use HDDRawCopy to convert the .imgc file to Raw/dd format.

    If you do not have a Windows machine, you can download the image I converted already, in .bz2 format from here:
    MATRICOM_MX2_115_FULL_AUG_09_2013.dd.bz2. Just extract it like this to get the raw image:

    $ cd ~/Downloads
$ bzip2 -d MATRICOM_MX2_115_FULL_AUG_09_2013.dd.bz2

  • Prepare the SD card:

    Note
    Make sure you don’t have any useful data on the SD card!

    First verify that the SD card is inserted:

      $ cat /proc/partitions 
  major minor  #blocks  name

      8        0  488386584 sda
      8        1     524288 sda1
      8        2     249856 sda2
      8        3  487610368 sda3
     11        0    1048575 sr0
   252        0  487608320 dm-0
   252        1  483524608 dm-1
   252        2    4067328 dm-2
   179        0    7761920 mmcblk0
   179        1      71680 mmcblk0p1
   179        2     124928 mmcblk0p2
   179        3    7559168 mmcblk0p3

    Unmount all partitions on the SD card:

    $ sudo umount /dev/mmcblk0p*

    Now use fdisk and delete all partitions from the SD card:

    $ sudo fdisk /dev/mmcblk0

  • Dump the image on the SD card:

    After preparing the SD card we need to dump the raw image on it:

    $ sudo dd if=MATRICOM_MX2_115_FULL_AUG_09_2013.dd of=/dev/mmcblk0

    Note
    Be very careful with dd! If you specify the wrong device on the of= parameter you may destroy useful data on other devices, even you main hard disk!

Boot the recovery image

Now we need to go though these steps to load the recovery image:

  1. Power off the XstreamTec appliance.

  2. Insert the SD card, in the SD slot of the XstreamTec.

  3. Press the reset button. This is somewhat tricky. The reset button is inside the AV port of the XstreamTec so you will need a toothpick to press it.

  4. Power on the appliance, while keeping the reset button pressed. The system will enter the recovery installation procedure. Release the reset button when the recovery starts.

  5. Follow the on-screen instructions to load the Android recovery image. Then reboot into android and see if it boots correctly.

Install the newer version of the Android system

Now we need to install a more recent version of Android on the XstreamTec.

  1. Download the newer Android firmware: 
    $ cd ~/Downloads
$ wget http://matriserver.com/files/MX2/firmware/MX2-full-1.1.6-firmware-RC.zip
  2. Prepare the SD card:

  • Insert the SD card in your PC and check if it is mounted:

    $ df -hT | grep mmc
    /dev/mmcblk0p1 vfat 3,7G 100M 3,6G 3% /media/user/0E99-207A

  • Delete all previous files from the SD card:

    $ cd /media/user/0E99-207A
    $ rm -fr *

    Note
    Once again make sure you don’t have any data you need on the SD card.

  1. Load the firmware on the SD card.

    Unzip the contents of the downloaded zip file (MX2-full-1.1.6-firmware-RC.zip) on the SD card:

    $ cd /media/user/0E99-207A
$ unzip ~/Downloads/MX2-full-1.1.6-firmware-RC.zip

Boot the new Android firmware

Go through these steps agaon to load the new Android firmware:

  1. Power off the XstreamTec appliance.

  2. Insert the SD card in the SD slot of the XstreamTec.

  3. Press the reset button. Repeat the toothpick procedure as previously.

  4. Power on the appliance while keeping the reset button pressed. The system will enter the new Android firmware installation procedure. Release the reset button when the recovery starts.

  5. Follow the on-screen instructions to load the new Android firmware. Then reboot into the new Android and see if it boots correctly.

One would be tempted to keep the Android system and use XBMC or install Kodi on it. This way you can have Android and XBMC/Kodi on your XstreamTec appliance. Alas the XBMC/Kodi experience for Android is not as good as the one on OpenELEC. Trust me, if you need the full Kodi experience you need to install OpenELEC.

Install OpenELEC on the XstreamTec HTPC media player

  1. Download the OpenELEC firmware: 
    $ cd ~/Downloads
$ wget https://www.dropbox.com/s/toe4kxi9ivomlmp/OpenELEC-Amlogic.MX2.arm-5.0.3.zip

    Update:
    There is a newer version at github.

  2. Prepare the SD card:

  • Insert the SD card in your PC and check if it is mounted:

    $ df -hT | grep mmc
    /dev/mmcblk0p1 vfat 3,7G 100M 3,6G 3% /media/user/0E99-207A

  • Delete all previous files from the SD card:

    $ cd /media/user/0E99-207A
    $ rm -fr *

  1. Load the OpenELEC firmware on the SD card.

    Unzip the contents of the downloaded zip file (OpenELEC-Amlogic.MX2.arm-5.0.3.zip) on the SD card:

    $ cd /media/user/0E99-207A
$ unzip ~/Downloads/OpenELEC-Amlogic.MX2.arm-5.0.3.zip

Boot the OpenELEC firmware

Once again repeat these steps to load the OpenELEC firmware:

  1. Power off the XstreamTec appliance.

  2. Insert the SD card in the SD slot of the XstreamTec.

  3. Press the reset button. Repeat the toothpick procedure as previously.

  4. Power on the appliance while keeping the reset button pressed. The system will enter the OpenELEC installation procedure. Release the reset button when the recovery starts.

  5. Follow the on-screen instructions to load the OpenELEC firmware. Then reboot into your freshly installed system and see if it works properly.

Enjoy your Kodi experience!

References

  • http://kodi.tv/
  • http://openelec.tv/
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Building a new Linux kernel for your Utilite Computer.

The Utilite computer comes with an aging Ubuntu 12.04. If you try to upgrade it to to 14.04 or later, you will end up with a broken system because of their dependency, either fully or partially, on the systemd init system. The problem is that the stock kernel does not support cgroups which is a mandatory dependency for systemd. Type these commands on your Utilite, to verify the missing feature:

$ sudo mount /dev/sda1 /boot
$ /usr/src/linux-kernel/scripts/extract-ikconfig /boot/uImage-cm-fx6 | grep CGROUPS
# CONFIG_CGROUPS is not set

There is also another important feature: fhandle. A systemd Linux system without an fhandle enabled kernel, will fail to enable the swap space during boot.

Most modern distros, with a few notable exceptions, have switched to this new initialization system. So if we want to use a recent version of Ubuntu, Debian or most other distros, we need to recompile the kernel with cgroups support.

Prerequisites

  • A standard x86-based PC with Linux installed (I use Ubuntu 15.04 at present). This is going to be our build station.
  • A Utilite ARM Computer. This is our target.

Prepare the cross-compile toolchain

The necessary packages are available on recent Ubuntu releases and Debian unstable.

First let’s install all necessary and optional packages on our build station:

$ sudo apt-get -y install build-essential gcc-arm-none-eabi gcc-arm-linux-gnueabi gcc-arm-linux-gnueabihf libncurses5 libncurses5-dev libncursesw5 libncursesw5-dev lzop git u-boot-tools pkg-config

Download the kernel sources

  1. You can download the sources from here: 
    $ wget https://github.com/utilite-computer/linux-kernel-3.0/archive/master.tar.gz
  2. Then extract the tarball and change into the kernel source root: 
    $ tar xvzf master.tar.gz
$ cd linux-kernel-3.0-master/

Building the kernel

  1. Prepare the environment: 
    $ export ARCH=arm
$ export CROSS_COMPILE=arm-linux-gnueabihf-
  2. Prepare the configuration for utilite: 
    $ make utilite_defconfig
  • Check if cgroups and fhandle are enabled: 
    $ grep CGROUPS .config
# CONFIG_CGROUPS is not set
$ grep FHANDLE .config
# CONFIG_FHANDLE is not set
  • Since cgroups and fhandle, are not enabled we need to enter menuconfig to enable it: 
    $ make menuconfig

    Navigate to General Setup and go down to Control Group support. Press the space bar and you will see an asterisk ([*]). That means the Control Group support feature is enabled to be compiled in the kernel. Now do the same with the open by fhandle syscalls option. Press exit and Yes to save your new configuration.

  • Make sure cgroups and fhandle are now enabled:

    $ grep CGROUPS .config
CONFIG_CGROUPS=y
$ grep FHANDLE .config
CONFIG_FHANDLE=y

    Good. Let’s proceed with the build.

  1. Build the kernel and prepare a U-boot compatible image (uImage):

    $ make
$ make uImage

    This will take some time depending on how powerful your build station is. Go for coffee, watch some movie, read a comic…

Prepare the tarball

Now we need to package the kernel and modules together.

  1. Install the modules in the rootfs directory: 
    $ mkdir -p rootfs/boot
$ INSTALL_MOD_PATH=./rootfs make modules_install

    Ignore this error after make modules_install:

    make[1]: *** No rule to make target 'rootfs/lib/firmware/./', needed by 'rootfs/lib/firmware/ti_3410.fw'.  Stop.
Makefile:1130: recipe for target '_modinst_post' failed
make: *** [_modinst_post] Error 2
  2. Copy the image and prepare the tarball: 
    $ cp arch/arm/boot/uImage rootfs/boot/uImage-cm-fx6
$ cp arch/arm/boot/zImage rootfs/boot/zImage-cm-fx6
$ cd rootfs
$ tar cvzf ../linux-utilite-kernel-3.0.tar.gz .
$ cd ..

Deploy the tarball

Now we are ready to deploy the kernel to the Utilite computer.

  1. Copy the kernel to the Utilite computer: 
    $ scp linux-utilite-kernel-3.0.tar.gz utilite@utilite-desktop:
  2. Now connect to the Utilite and mount the boot partition: 
    $ sudo mount /dev/sda1 /boot
  3. Backup the existing files and remove the old image and modules: 
    $ tar cvzf linux-utilite-original-kernel.tar.gz /boot/ /lib/modules/3.0.35-cm-fx6-6.3/
$ sudo rm /boot/uImage-cm-fx6
$ sudo rm -fr /lib/modules/3.0.35-cm-fx6-6.3

    If something goes wrong you can boot from a microSD or a USB drive and restore the original kernel.

  • Deploy the kernel:

    Note
    Make sure the /boot directory is mounted on the /dev/sda1 filesystem before running the following command. 

    $ sudo tar xvzf linux-utilite-kernel-3.0.tar.gz -C /
$ sudo chown -R root:root /lib/modules/3.0.35-cm-fx6-6.4
$ sudo depmod 3.0.35-cm-fx6-6.4

    The errors caused by tar are produced because FAT filesystem like /dev/sda1, do not support the ownership attribute. You can safely ignore them. chown is used to set the owneship of the modules to the root user, since the tarball was packaged under a normal user account and inherited its permissions.

    • You can now reboot the Utilite and see if everything works as expected. If not, you can boot with a microSD or a USB flash drive and restore the original kernel and modules.

    After we have successfully prepared a cgroups enabled kernel, we can move on to setup a new Ubuntu or Debian system on the Utilite.

    References

    • [1] http://www.compulab.co.il/utilite-computer/wiki/index.php/Utilite_Linux_Kernel_3.0