c0d3 :: j0rg3

A collection of tips, tricks and snips. A proud Blosxom weblog. All code. No cruft.

Sun, 19 Feb 2017

Privacy: perspective and primer.

Hello friends.

While the overall telos of this blog is to, generally speaking, convey code snippets and inspire the personal projects of others, today we’re going to do something a smidgeon different.

This will be a layman’s look at varied dimensions of information security from a comfortable distance. Over the years, I’ve secured servers, operating systems, medical data, networks, communications and I’ve unsecured many of these same things. The topics are too sprawling to be covered in a quick summary — but let’s find a point of entry.

Those of us who are passionate about information security are well aware of how daunting is the situation. For newcomers, it sometimes seems rather impossible. Pick any subject and there are probably well-informed and convincing experts in diametric equidistance from any “happy medium”.

Let’s imagine that (like most of us) you don’t have anything spectacular to protect. However, you dislike the idea of our ever-dissolving privacy. Therefore you want to encrypt communications. Maybe you begin to use Signal. However, there are criticisms that there is a “backdoor” (there is not). Further, there are accusations that open source projects are coded by those who can’t get real jobs. Conversely, open source projects are widely open for peer review. If it worries one enough they are free to review code themselves.

PGP can encrypt content but concerns surround algorithmic selections. Some are worried about metadata crumbs. Of course, there’s nothing preventing the frequent switching of keys and email addresses. You could use BitMessage, any number of chat solutions or drop at paste bins.

Let’s leave those concerns aside for when you’ve figured out what you’re intending to protect. These arguments surround any subject in information security and we’re not going to investigate them on a case by case basis. Least, not in this post.

At the coarsest granularity, the question is analogous to the practicality of locking your doors or sealing your post envelopes. Should I take measures toward privacy?

My opinion is rather predictable: of course you should!

There’s a very pragmatic explanation. If there ever comes a day when you should like to communicate privately, that’s a terrible time to start learning.

Take the easy road and start using some of the myriad tools and services available.

Should you decide to take InfoSec seriously, you’ll need to define a threat model.
That is: What am I protecting? From whom am I protecting? (e.g. what are probable attack vectors?)

That’s where you need to make choices about trusting products, protocols, methods, algorithms, companies, servers, et cet. Those are all exciting subjects to explore but all too often brushing up against them can be exasperating and cause premature burn-out.

That in mind, let’s employ the philosophy that any effort toward security is better than none and take a look at a few points where one might get wetted-toes.

If you have questions or want specific advice, there are several ways below to initiate a secure conversation with me.

 

Secure your browser:

  • Privacy Badger: Block tracking
  • HTTPS Everywhere: Increase your encryptioning
  • uBlock: Advertisements are for others
  •  

    Secure communications:

  • Mailvelope: PGP email encryption for your major webmail provider (e.g., Gmail) | contact | pubkey
  • Tutanota: Encrypted webmail | Kontakt
  • Protonmail: Well-established provider of PGP encrypted webmail, featuring 2FA | kontakta
  • BitMessage: P2P encrypted communications protocol | contact: BM-2D9tDkYEJSTnEkGDKf7xYA5rUj2ihETxVR | Bitmessage channel list
  •   [ Bitmessage in a Docker container ]

  • BitMessage.ch: BitMessage email gateway | contact
  • BitMsg.me: Online BitMessage service
  • Keybase.io: Keybase maps your identity to your public keys, and vice versa
  • Signal: PGP encrypted TXT messages
  • Wire: Encrypted chat, video and calls
  • RIOT: Open-source, IRC-based, Matrix; run your own server
  • Wickr: Encrypted ephemeral chat
  •   [ n.b. Wickr’s .deb package seeks a unicode library (libicu52) which is not available to a recent Kali (or anything) install; .deb file is based on Ubuntu’s 2014 LTS release. Wickr in a Docker container ]

     

    Explore alternate nets (e.g., Deep Web, Dark Net):

  • MaidSafe: Promising new alt-web project
  • Qubes: a reasonably secure operating system
  • FreeNet: Alt-net based primarily on already knowing with whom you intend to collaborate
  • Bitmask: VPN solution to anonymize your traffic
  • TAILS: A live operating system based on the Tor network
  • TorBrowser: Stand-alone browser for Tor (less secure than TAILS)
  • Whonix: the most secure (and complex) way to access the Tor network
  • i2p: an other approach to creating a secure and private alternate web
  • Morph.is: fun alt-net, aimed at producing The World Brain. Although, it’s future looks a lot less promising since the lead dev was killed.
  • ZeroNet: one more encrypted anonymous net
  • Have fun and compute safely!


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    Permalink: 20170219.privacy.prespective.primer

    Sat, 18 Feb 2017

    The making of a Docker: Part II - Wickr: with bonus analysis

    Recently, I read a rather excited attention-catching piece about how Wickr is the super-secure version of Slack. Attention caught in part because I feel like Wickr has been around for a while. I’d not seen anyone raving about its security in places where I normally interact with those who are highly informed about such subjects.

    Good is that it seems the folk at Wickr did a fine job of making sure valuable data aren’t left behind.
    The bad: closed-source, not subject to independent review; crazy marketin’-fancy-talk without a thorough description of how it does what is claimed.
    Any time I’m looking at a product or service that boasts security, I sort of expect to see a threat model.

    [ Update: At the time I was working on this project, the folk at Wickr were, evidently, opening their source. That’s spectacular news! Check it out on Github. ]

    This began as an exercise to provide another piece of security-ish software in a Docker container. Anyone who has used a live distro (e.g., Kali, TAILS) with any regularity knows the ritual of installing favorite tools at each boot, data stores on removable media.

    For me, there is tremendous appeal in reducing that to something like:
    git clone https://georgeglarson/wickr
    cd docker-wickr
    ./install.sh
    wickr

    Let’s dig in!

    Having created a number of Docker containers my workflow is to queue up the base OS and go through the steps needed to get the software running while keeping careful notes. In this case, I had originally tried to install Wickr on a current copy of Kali. It was already known that Wickr, based off of Ubuntu 14.04, needed an older unicode library. So we begin with Ubuntu 14.04.

    Grab a copy of Wickr and see what’s required:
    dpkg -I wickr-me_2.6.0_amd64.deb

    new debian package, version 2.0.
    size 78890218 bytes: control archive=4813 bytes.
    558 bytes, 14 lines control
    558 bytes, 14 lines control64
    10808 bytes, 140 lines md5sums
    Package: wickr-me
    Architecture: amd64
    Section: net
    Priority: optional
    Version: 2.6.0-4
    Replaces: wickr
    Conflicts: wickr
    Depends: libsqlcipher0, libuuid1, libicu52, libavutil52|libavutil54, libc6, libssl1.0.0, libx264-142, libglib2.0-0, libpulse0, libxrender1, libgl1-mesa-glx
    Recommends: libnotify-bin, gstreamer-plugins0.10-good, gstreamer-plugins0.10-bad, gstreamer-plugins0.10-ugly
    Maintainer: Wickr Inc.
    Installed-Size: 200000
    Description: Secure Internet Chat and Media Exchange agent
    Wickr is a secure communications client

    Okay. The CLI should do most of the work for us, giving a formatted list of dependencies.
    dpkg -I wickr-me_2.6.0_amd64.deb | grep -E "^ Depends: | Recommends: " | sed -e "s/ Depends: //" -e "s/ Recommends: //" -e "s/,//g" -e "s/ / \\\ \n/g"

    libsqlcipher0 \
    libuuid1 \
    libicu52 \
    libavutil54 \
    libc6 \
    libssl1.0.0 \
    libx264-142 \
    libglib2.0-0 \
    libpulse0 \
    libxrender1 \
    libgl1-mesa-glx
    libnotify-bin \
    gstreamer-plugins0.10-good \
    gstreamer-plugins0.10-bad \
    gstreamer-plugins0.10-ugly \

    Attempting to get those with apt-get reports that it cannot find the gstreamer bits.

    Let’s find:
    apt-cache search gstreamer | grep -i plugin | grep -E "good|bad|ugly"

    gstreamer0.10-plugins-good - GStreamer plugins from the "good" set
    ...
    gstreamer0.10-plugins-bad - GStreamer plugins from the "bad" set
    ...
    gstreamer0.10-plugins-ugly - GStreamer plugins from the "ugly" set

    So, there’s the format we need to get the gstreamer dependencies. We know that we’ll also want SSH and wget. That should be enough for our Dockerfile.

    We’ll pull down Wickr:
    wget https://dls.wickr.com/Downloads/wickr-me_2.6.0_amd64.deb

    Then install:
    dpkg -i wickr-me_2.6.0_amd64.deb

    Okay! We are, in theory, ready to run Wickr. We’re about to see we aren’t yet there — but these sorts of problems are pretty commonplace.
    wickr-me

    wickr-me: error while loading shared libraries: libxslt.so.1: cannot open shared object file: No such file or directory

    Huh! We need libxslt. Let’s fix that: apt-get install libxslt1-dev

    Now we can run it.
    wickr-me

    This application failed to start because it could not find or load the Qt platform plugin "xcb".

    Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, xcb.

    Reinstalling the application may fix this problem.
    Aborted (core dumped)

    One more: apt-get install xcb

    Okay. That really was the last one. Now we have a complete list of dependencies for our Dockerfile:
    RUN apt-get update && apt-get install -y \
    gstreamer0.10-plugins-good \
    gstreamer0.10-plugins-bad \
    gstreamer0.10-plugins-ugly \
    libsqlcipher0 \
    libuuid1 \
    libicu52 \
    libavutil52 \
    libc6 \
    libssl1.0.0 \
    libx264-142 \
    libglib2.0-0 \
    libpulse0 \
    libxrender1 \
    libxslt1-dev \
    libgl1-mesa-glx \
    libnotify-bin \
    ssh \
    wget \
    xcb \
    && apt-get clean \

    We now have Wickr in a Docker container and, because we are the curious sort, need to peek into what’s happening.

    A natural first step is to set Wireshark atop Wickr. At a glance, seems to be communicating with a single IP address (204.232.166.114) via HTTPS.

    Unsurprsingly, the client communicates to the server whenever a message is sent. Further it appears to poll the same address periodically asking for new messages. We see that the address resolves to Rackspace in San Antonio, TX.

    We can easily establish the link between this IP address, Rackspace and the application.

    Well, that’s enough. Right?

    Good!

    Wait.

    What?

    We’re still a little curious.

    Aren’t we?

    I mean, what’s the big question here? What happens if there’s a man in the middle? Persons so eagerly connect to any free WIFI, it is clearly a plausible scenario. Well… One way to find out!

    Here’s what we learned. Server-side, the application is written in PHP. The IP address is resolved by the URI ‘secex.info’.

    When we send, it calls ‘postMessage.php’:

    When we receive, ‘downloadMessage.php’:

    And it calls ‘newMessageCheck.php’ to, y’know, check for new messages.

    Other analyses have forensically examined artefacts left behind; there are published descriptions of the encryption methods used for the local database connection. We didn’t go into more aggressive efforts such as disassembly because we are too lazy for that jazz!

    My opinion, we didn’t learn anything wildly unexpected. Overall, Wickr seems an okay solution for convenient encrypted messaging. That’s always the trade: convenience vs. security. Least we ended with a Docker container for the software!

    Github | Docker


    Tags: , , ,
    Permalink: 20170218.making.a.docker.wickr

    Sat, 25 Jan 2014

    Network-aware Synergy client

    My primary machines are *nix or BSD variants, though I certainly have some Windows-based rigs also. Today we’re going to share some love with Windows 7 and PowerShell.

    One of my favorite utilities is Synergy. If you’re not already familiar it allows to you seamlessly move from the desktop of one computer to another with the same keyboard and mouse. It even supports the clipboard so you might copy text from a GNU/Linux box and paste it in a Windows’ window. Possibly, they have finished adding drag and drop to the newer versions. I am not sure because I run a relatively old version that is supported by all of the machines that I use regularly.

    What’s the problem, then? The problem was that I was starting my Synergy client by hand. Even more disturbing, I was manually typing the IP address at work and at home, twice or more per weekday. This behavior became automated by my brain and continued for months unnoticed. But this is no kind of life for a geek such as myself, what with all this superfluous clicking and tapping!

    Today, we set things right!

    In my situation, the networks that I use happen to assign IP addresses from different subnets. If you’ve not the convenience of that situation then you might need to add something to the script. Parsing an ipconfig/ifconfig command, you could possibly use something like the Default Gateway or the Connection-specific DNS Suffix. Alternatively, you could check for the presence of some network share, a file on server or anything that would allow you to uniquely identify the surroundings.

    As I imagined it, I wanted the script to accomplish the following things

    • see if Synergy is running (possibly from the last location), if so ask if we need to kill it and restart so we can identify a new server
    • attempt to locate where we are and connect to the correct Synergy server
    • if the location is not identified, ask whether to start the Synergy client

    This is how I accomplished that task:

    # [void] simply supresses the noise made loading 'System.Reflection.Assembly'
    [void] [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")

    # Define Synergy server IP addresses
    $synergyServerWork = "192.168.111.11"
    $synergyServerHome = "192.168.222.22"

    # Define partial IP addresses that will indicate which server to use
    $synergyWorkSubnets = "192.168.111", "192.168.115"
    $synergyHomeSubnets = "192.168.222", "192.168.225"

    # Path to Synergy Client (synergyc)
    $synergyClientProgram = "C:\Program Files\Synergy\synergyc.exe"

    # Path to Syngery launcher, for when we cannot identify the network
    $synergyLauncherProgram = "C:\Program Files\Synergy\launcher.exe"

    # Remove path and file extension to give us the process name
    $processName = $synergyClientProgram.Substring( ($synergyClientProgram.lastindexof("\") + 1), ($synergyClientProgram.length - ($synergyClientProgram.lastindexof("\") + 5) ))

    # Grab current IP address
    $currentIPaddress = ((ipconfig | findstr [0-9].\.)[0]).Split()[-1]

    # Find the subnet of current IP address
    $location = $currentIPaddress.Substring(0,$currentIPaddress.lastindexof("."))


    function BalloonTip ($message)
    {
    # Pop-up message from System Tray
    $objNotifyIcon = New-Object System.Windows.Forms.NotifyIcon
    $objNotifyIcon.Icon = [System.Drawing.Icon]::ExtractAssociatedIcon($synergyClientProgram)
    $objNotifyIcon.BalloonTipText = $message
    $objNotifyIcon.Visible = $True
    $objNotifyIcon.ShowBalloonTip(15000)
    }


    #main

    # If Synergy client is already running, do we need to restart it?
    $running = Get-Process $processName -ErrorAction SilentlyContinue
    if ($running) {
    $answer = [System.Windows.Forms.MessageBox]::Show("Synergy is running.`nClose and start again?", "OHNOES", 4)
    if ($answer -eq "YES") {
    Stop-Process -name $processName
    }
    Else {
    exit
    }
    }

    # Do we recognize the current network?
    if ($synergyWorkSubnets -contains $location) {
    BalloonTip "IP: $($currentIPaddress)`nServer: $($synergyServerWork)`nConnecting to Synergy server at work."
    & $synergyClientProgram $synergyServerWork
    exit
    }
    ElseIf ($synergyHomeSubnets -contains $location) {
    BalloonTip "IP: $($currentIPaddress)`nServer: $($synergyServerHome)`nConnecting to Synergy server at home."
    & $synergyClientProgram $synergyServerHome
    exit
    }
    Else {
    $answer = [System.Windows.Forms.MessageBox]::Show("Network not recognized by IP address: {0}`n`nLaunch Synergy?" -f $unrecognized, "OHNOES", 4)
    if ($answer -eq "YES") {
    & $synergyLauncherProgram
    }
    }

    Then I saved the script in "C:\Program Files\SynergyStart\", created a shortcut and used the Change Icon button to make the same as Synergy’s and made the Target:
    C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -WindowStyle Hidden & 'C:\Program Files\SynergyStart\synergy.ps1'

    Lastly, I copied the shortcut into the directory of things that run when the system starts up:
    %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup

    Now, Synergy connects to the needed server at home and work. If it can’t figure out where it is, it asks if it should run it at all.

    As they say, a millisecond saved is a millisecond earned.

    This post was very nearly published without a Linux equivalent. Nearly.

    Same trick for bash/zsh: #!/bin/zsh

    # Define Synergy server IP addresses
    synergyServerWork="192.168.111.11"
    synergyServerHome="192.168.222.22"

    # Define partial IP addresses that will indicate which server to use
    synergyWorkSubnets=("192.168.111" "192.168.115")
    synergyHomeSubnets=("192.168.222" "192.168.225")

    # Path to Synergy Client (synergyc)
    synergyClientProgram="/usr/bin/synergyc"

    # Path to QuickSyngery, for when we cannot identify the network
    synergyLauncherProgram="/usr/bin/quicksynergy"

    # Remove path and file extension to give us the process name
    processName=`basename $synergyClientProgram`

    # Grab current IP address, assumes '192' is in use. (e.g., 192.168.1.1)
    currentIPaddress=`ip addr show | grep 192 | awk "{print $2}" | sed 's/inet //;s/\/.*//;s/ //g'`

    # Find the subnet of current IP address
    location=`echo $currentIPaddress | cut -d '.' -f 1,2,3`

    for i in "${synergyWorkSubnets[@]}"
    do
    if [ "${i}" = "${location}" ]
    then
    break
    fi
    done

    #main

    # If Synergy client is already running, do we need to restart it?
    running=`ps ax | grep -v grep | grep $processName`
    if [ $running ]
    then
    if `zenity --question --ok-label="Yes" --cancel-label="No" --text="Synergy is running.\nClose and start again?"`
    then
    pkill $processName
    else
    exit
    fi
    fi

    # Do we recognize the current network?
    for i in "${synergyWorkSubnets[@]}"
    do
    if [ "${i}" = "${location}" ]
    then
    notify-send "IP:$currentIPaddress Server:$synergyServerWork [WORK]"
    $synergyClientProgram $synergyServerWork
    exit
    fi
    done

    for i in "${synergyHomeSubnets[@]}"
    do
    if [ "${i}" = "${location}" ]
    then
    notify-send "IP:$currentIPaddress Server:$synergyServerWork [HOME]"
    $synergyClientProgram $synergyServerHome
    exit
    fi
    done

    if `zenity --question --ok-label="Yes" --cancel-label="No" --text="Network not recognized by IP address: $currentIPaddress\nLaunch Synergy?"`
    then
    $synergyLauncherProgram
    fi

    To get it to run automatically, you might choose to call the script from /etc/init.d/rc.local.

    Download here:
      PowerShell:
        synergy.ps1
      GNU/Linux:
        synergy.sh


    Tags: , ,
    Permalink: 20140125.network_aware_synergy_client