598 lines
124 KiB
XML
598 lines
124 KiB
XML
<?xml version="1.0" encoding="utf-8"?><feed xmlns="http://www.w3.org/2005/Atom" ><generator uri="https://jekyllrb.com/" version="3.8.6">Jekyll</generator><link href="http://0.0.0.0:4000/feed.xml" rel="self" type="application/atom+xml" /><link href="http://0.0.0.0:4000/" rel="alternate" type="text/html" /><updated>2019-08-02T17:05:57-04:00</updated><id>http://0.0.0.0:4000/feed.xml</id><title type="html">Evan Pratten</title><subtitle>Computer wizard, student, <a href="https://frc5024.github.io">@frc5024</a> programming team lead, and radio enthusiast.</subtitle><entry><title type="html">Mind map generation with Python</title><link href="http://0.0.0.0:4000/blog/2019/07/15/mindmap" rel="alternate" type="text/html" title="Mind map generation with Python" /><published>2019-07-15T14:38:00-04:00</published><updated>2019-07-15T14:38:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/07/15/MindMap</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/07/15/mindmap"><p>While working on an assignment with <a href="https://coggle.it">Coggle</a> today, I noticed an interesting option in the save menu. <em>Download as .mm file</em>. Having rarely worked with mind maps before, and only doing it online, it never occured to me that someone would have a file format for it. So I took a look.</p>
|
||
|
||
<h2 id="what-is-a-mm-file">What is a .mm file?</h2>
|
||
<p>It turns out, a <code class="highlighter-rouge">.mm</code> file is just some XML describing the mind map. Here is a simple mind map:</p>
|
||
|
||
<p><img src="/assets/images/mindmap-simple.png" alt="Simple Mind Map" /></p>
|
||
|
||
<p>And again as a <code class="highlighter-rouge">.mm</code> file:</p>
|
||
|
||
<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;map</span> <span class="na">version=</span><span class="s">"0.9.0"</span><span class="nt">&gt;</span>
|
||
<span class="nt">&lt;node</span> <span class="na">TEXT=</span><span class="s">"Master Node"</span> <span class="na">FOLDED=</span><span class="s">"false"</span> <span class="na">POSITION=</span><span class="s">"right"</span> <span class="na">ID=</span><span class="s">"5d2d02b1a315dd0879f48c1c"</span> <span class="na">X_COGGLE_POSX=</span><span class="s">"0"</span> <span class="na">X_COGGLE_POSY=</span><span class="s">"0"</span><span class="nt">&gt;</span>
|
||
<span class="nt">&lt;edge</span> <span class="na">COLOR=</span><span class="s">"#b4b4b4"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;font</span> <span class="na">NAME=</span><span class="s">"Helvetica"</span> <span class="na">SIZE=</span><span class="s">"17"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;node</span> <span class="na">TEXT=</span><span class="s">"Child branch"</span> <span class="na">FOLDED=</span><span class="s">"false"</span> <span class="na">POSITION=</span><span class="s">"right"</span> <span class="na">ID=</span><span class="s">"f72704969525d2a0333dd635"</span><span class="nt">&gt;</span>
|
||
<span class="nt">&lt;edge</span> <span class="na">COLOR=</span><span class="s">"#7aa3e5"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;font</span> <span class="na">NAME=</span><span class="s">"Helvetica"</span> <span class="na">SIZE=</span><span class="s">"15"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;node</span> <span class="na">TEXT=</span><span class="s">"Children 1"</span> <span class="na">FOLDED=</span><span class="s">"false"</span> <span class="na">POSITION=</span><span class="s">"right"</span> <span class="na">ID=</span><span class="s">"c83826af506cae6e55761d5c"</span><span class="nt">&gt;</span>
|
||
<span class="nt">&lt;edge</span> <span class="na">COLOR=</span><span class="s">"#7ea7e5"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;font</span> <span class="na">NAME=</span><span class="s">"Helvetica"</span> <span class="na">SIZE=</span><span class="s">"13"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;/node&gt;</span>
|
||
<span class="nt">&lt;node</span> <span class="na">TEXT=</span><span class="s">"Children 2"</span> <span class="na">FOLDED=</span><span class="s">"false"</span> <span class="na">POSITION=</span><span class="s">"right"</span> <span class="na">ID=</span><span class="s">"47723a4d0fb766863f70d204"</span><span class="nt">&gt;</span>
|
||
<span class="nt">&lt;edge</span> <span class="na">COLOR=</span><span class="s">"#82aae7"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;font</span> <span class="na">NAME=</span><span class="s">"Helvetica"</span> <span class="na">SIZE=</span><span class="s">"13"</span><span class="nt">/&gt;</span>
|
||
<span class="nt">&lt;/node&gt;</span>
|
||
<span class="nt">&lt;/node&gt;</span>
|
||
<span class="nt">&lt;/node&gt;</span>
|
||
<span class="nt">&lt;/map&gt;</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Neat, right?</p>
|
||
|
||
<h2 id="what-can-we-do-with-it">What can we do with it?</h2>
|
||
<p>I have not done much research about this because I wanted to work all of this out on my own. But I know one thing as a fact: working with XML sucks (especially in Python). I decided that this would be much better if I could load <code class="highlighter-rouge">.mm</code> files as JSON. This would allow easy manipulation and some cool projects.</p>
|
||
|
||
<h2 id="my-script">My script</h2>
|
||
<p>Like everything I do, I made a script to play with these files.</p>
|
||
|
||
<p>It’s pretty simple. First, It loads a <code class="highlighter-rouge">.mm</code> file, then parses it into a <code class="highlighter-rouge">list</code> of <code class="highlighter-rouge">xml.etree.ElementTree.Element</code>.</p>
|
||
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">raw_mm</span> <span class="o">=</span> <span class="s">""</span>
|
||
|
||
<span class="k">with</span> <span class="nb">open</span><span class="p">(</span><span class="n">args</span><span class="o">.</span><span class="nb">file</span><span class="p">,</span> <span class="s">"r"</span><span class="p">)</span> <span class="k">as</span> <span class="n">fp</span><span class="p">:</span>
|
||
<span class="n">raw_mm</span> <span class="o">=</span> <span class="n">fp</span><span class="o">.</span><span class="n">read</span><span class="p">()</span>
|
||
<span class="n">fp</span><span class="o">.</span><span class="n">close</span><span class="p">()</span>
|
||
|
||
<span class="n">xml</span> <span class="o">=</span> <span class="n">ET</span><span class="o">.</span><span class="n">fromstring</span><span class="p">(</span><span class="n">raw_mm</span><span class="p">)</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>The parsed <code class="highlighter-rouge">list</code> is then passed into a recursive function that constructs a <code class="highlighter-rouge">dict</code></p>
|
||
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">def</span> <span class="nf">xmlToDict</span><span class="p">(</span><span class="n">xml</span><span class="p">):</span>
|
||
<span class="n">output</span> <span class="o">=</span> <span class="p">[]</span>
|
||
<span class="k">for</span> <span class="n">elem</span> <span class="ow">in</span> <span class="nb">list</span><span class="p">(</span><span class="n">xml</span><span class="p">):</span>
|
||
|
||
<span class="k">if</span> <span class="s">"TEXT"</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">elem</span><span class="o">.</span><span class="n">attrib</span><span class="p">:</span>
|
||
<span class="k">continue</span>
|
||
|
||
<span class="n">name</span> <span class="o">=</span> <span class="n">elem</span><span class="o">.</span><span class="n">attrib</span><span class="p">[</span><span class="s">'TEXT'</span><span class="p">]</span>
|
||
<span class="n">json_element</span> <span class="o">=</span> <span class="p">{</span><span class="s">"name"</span><span class="p">:</span> <span class="n">name</span><span class="p">}</span>
|
||
|
||
<span class="k">try</span><span class="p">:</span>
|
||
<span class="n">json_element</span><span class="p">[</span><span class="s">"children"</span><span class="p">]</span> <span class="o">=</span> <span class="n">xmlToDict</span><span class="p">(</span><span class="n">elem</span><span class="p">)</span>
|
||
<span class="k">except</span><span class="p">:</span>
|
||
<span class="k">continue</span>
|
||
|
||
<span class="c1"># Detect node type
|
||
</span> <span class="k">if</span> <span class="n">json_element</span><span class="p">[</span><span class="s">"children"</span><span class="p">]:</span>
|
||
<span class="n">json_element</span><span class="p">[</span><span class="s">"type"</span><span class="p">]</span> <span class="o">=</span> <span class="s">"branch"</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="n">json_element</span><span class="p">[</span><span class="s">"type"</span><span class="p">]</span> <span class="o">=</span> <span class="s">"leaf"</span>
|
||
<span class="k">del</span> <span class="n">json_element</span><span class="p">[</span><span class="s">"children"</span><span class="p">]</span>
|
||
|
||
<span class="n">output</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">json_element</span><span class="p">)</span>
|
||
|
||
<span class="k">return</span> <span class="n">output</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Finally, the <code class="highlighter-rouge">dict</code> is written to a file with <code class="highlighter-rouge">json.dump</code></p>
|
||
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">json</span><span class="o">.</span><span class="n">dump</span><span class="p">(</span><span class="n">mind_map</span><span class="p">,</span> <span class="nb">open</span><span class="p">(</span><span class="n">args</span><span class="o">.</span><span class="nb">file</span> <span class="o">+</span> <span class="s">".json"</span><span class="p">,</span> <span class="s">"w"</span><span class="p">))</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>The whole script (with comments) can be found on my <a href="https://gist.github.com/Ewpratten/0d8f7c7371380c9ca8adcfc6502ccf84#file-parser-py">GitHub account</a>.</p>
|
||
|
||
<h2 id="the-output">The output</h2>
|
||
<p>Running the <code class="highlighter-rouge">.mm</code> file from above through the script gives:</p>
|
||
|
||
<div class="language-json highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="p">[</span><span class="w">
|
||
</span><span class="p">{</span><span class="w">
|
||
</span><span class="nl">"name"</span><span class="p">:</span><span class="s2">"Master Node"</span><span class="p">,</span><span class="w">
|
||
</span><span class="nl">"children"</span><span class="p">:[</span><span class="w">
|
||
</span><span class="p">{</span><span class="w">
|
||
</span><span class="nl">"name"</span><span class="p">:</span><span class="s2">"Child branch"</span><span class="p">,</span><span class="w">
|
||
</span><span class="nl">"children"</span><span class="p">:[</span><span class="w">
|
||
</span><span class="p">{</span><span class="w">
|
||
</span><span class="nl">"name"</span><span class="p">:</span><span class="s2">"Children 1"</span><span class="p">,</span><span class="w">
|
||
</span><span class="nl">"type"</span><span class="p">:</span><span class="s2">"leaf"</span><span class="w">
|
||
</span><span class="p">},</span><span class="w">
|
||
</span><span class="p">{</span><span class="w">
|
||
</span><span class="nl">"name"</span><span class="p">:</span><span class="s2">"Children 2"</span><span class="p">,</span><span class="w">
|
||
</span><span class="nl">"type"</span><span class="p">:</span><span class="s2">"leaf"</span><span class="w">
|
||
</span><span class="p">}</span><span class="w">
|
||
</span><span class="p">],</span><span class="w">
|
||
</span><span class="nl">"type"</span><span class="p">:</span><span class="s2">"branch"</span><span class="w">
|
||
</span><span class="p">}</span><span class="w">
|
||
</span><span class="p">],</span><span class="w">
|
||
</span><span class="nl">"type"</span><span class="p">:</span><span class="s2">"branch"</span><span class="w">
|
||
</span><span class="p">}</span><span class="w">
|
||
</span><span class="p">]</span><span class="w">
|
||
</span></code></pre></div></div>
|
||
|
||
<h2 id="the-next-step">The next step</h2>
|
||
<p>This script just translates a <code class="highlighter-rouge">.mm</code> file to JSON. Nothing else. Next, I want to convert this to a library, and add a JSON to <code class="highlighter-rouge">.mm</code> function as well. This leads into my ultimate goal for this project.</p>
|
||
|
||
<p>I want a script that I can drop in the root of any project to build a <a href="https://gource.io/">Gource</a>-style visualization of the folder structure. This will give me a way to make cool visualizations for lessons on the robotics team.</p></content><author><name></name></author><summary type="html">While working on an assignment with Coggle today, I noticed an interesting option in the save menu. Download as .mm file. Having rarely worked with mind maps before, and only doing it online, it never occured to me that someone would have a file format for it. So I took a look.</summary></entry><entry><title type="html">Taking a look back at GMAD</title><link href="http://0.0.0.0:4000/blog/2019/07/13/lookback-gmad" rel="alternate" type="text/html" title="Taking a look back at GMAD" /><published>2019-07-13T10:43:00-04:00</published><updated>2019-07-13T10:43:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/07/13/Lookback-GMAD</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/07/13/lookback-gmad"><p>One day, back in June of 2018, I was both looking for a new project to work on, and trying to decide which Linux distro to install on one of my computers. From this, a little project was born. <a href="/gmad">Give Me a Distro</a> (or, GMAD, as I like to call it) is a little website that chooses a random distribution of Linux and shows a description of what you are about to get yourself into, and a download link for the latest ISO.</p>
|
||
|
||
<h2 id="backend-tech">Backend tech</h2>
|
||
<p>This is one of the simplest projects I have ever made. All the backend does is:</p>
|
||
<ul>
|
||
<li>Select a random number (n)</li>
|
||
<li>Fetch the nth item from a list of distros</li>
|
||
<li>Push the selected data to the user via DOM</li>
|
||
</ul>
|
||
|
||
<h2 id="frontend">Frontend</h2>
|
||
<p>This website is just plain HTML and CSS3, built without any CSS framework.</p>
|
||
|
||
<h2 id="my-regrets">My regrets</h2>
|
||
<p>There are two things I do not like about this project. Firstly, on load, the site breifly suggests Arch Linux before flashing to the random selection. This is due to the fact that Arch is the default for people with Javascript disabled. Some kind of loading animation would fix this.</p>
|
||
|
||
<p>Secondly, the version of the site hosted on <a href="https://retrylife.ca/gmad">retrylife.ca</a> is actually just an iframe to <a href="https://ewpratten.github.io/GiveMeADistro">ewpratten.github.io</a> due to some CNAME issues.</p>
|
||
|
||
<h2 id="contributing">Contributing</h2>
|
||
<p>If you would like to add a distro or three to the website, feel free to make a pull request over on <a href="https://github.com/Ewpratten/GiveMeADistro">GitHub</a>.</p>
|
||
|
||
<h2 id="why-make-a-post-about-it-a-year-later">Why make a post about it a year later?</h2>
|
||
<p>I just really enjoyed working with the project and sharing it with friends, so I figured I should mention it here too. Maybe it will inspire someone to make something cool!</p></content><author><name></name></author><summary type="html">One day, back in June of 2018, I was both looking for a new project to work on, and trying to decide which Linux distro to install on one of my computers. From this, a little project was born. Give Me a Distro (or, GMAD, as I like to call it) is a little website that chooses a random distribution of Linux and shows a description of what you are about to get yourself into, and a download link for the latest ISO.</summary></entry><entry><title type="html">Scraping FRC team’s GitHub accounts to gather large amounts of data</title><link href="http://0.0.0.0:4000/blog/2019/07/06/scrapingfrcgithub" rel="alternate" type="text/html" title="Scraping FRC team's GitHub accounts to gather large amounts of data" /><published>2019-07-06T11:08:00-04:00</published><updated>2019-07-06T11:08:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/07/06/ScrapingFRCGithub</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/07/06/scrapingfrcgithub"><p>I was curious about the most used languages for FRC, so I build a Python script to find out what they where.</p>
|
||
|
||
<h2 id="some-basic-data">Some basic data</h2>
|
||
<p>Before we get to the heavy work done by my script, let’s start with some general data.</p>
|
||
|
||
<p>Thanks to the <a href="https://www.thebluealliance.com/apidocs/v3">TBA API</a>, I know that there are 6917 registered teams. 492 of them have registered at least one account on GitHub.</p>
|
||
|
||
<h2 id="how-the-script-works">How the script works</h2>
|
||
<p>The script is split into steps:</p>
|
||
<ul>
|
||
<li>Get a list of every registered team</li>
|
||
<li>Check for a github account attached to every registered team
|
||
<ul>
|
||
<li>If a team has an account, it is added to the dataset</li>
|
||
</ul>
|
||
</li>
|
||
<li>Load each github profile
|
||
<ul>
|
||
<li>If it is a private account, move on</li>
|
||
<li>Use Regex to find all languages used</li>
|
||
</ul>
|
||
</li>
|
||
<li>Compile data and sort</li>
|
||
</ul>
|
||
|
||
<h3 id="getting-a-list-of-accounts">Getting a list of accounts</h3>
|
||
<p>This is probably the simplest step in the whole process. I used the auto-generated <a href="https://github.com/TBA-API/tba-api-client-python">tbaapiv3client</a> python library’s <code class="highlighter-rouge">get_teams_keys(key)</code> function, and kept incrementing <code class="highlighter-rouge">key</code> until I got an empty array. All returned data was then added together into a big list of team keys.</p>
|
||
|
||
<h3 id="checking-for-a-teams-github-account">Checking for a team’s github account</h3>
|
||
<p>The <a href="https://www.thebluealliance.com/apidocs/v3">TBA API</a> helpfully provides a <code class="highlighter-rouge">/api/v3/team/&lt;number&gt;/social_media</code> API endpoint that will give the GitHub username for any team you request. (or nothing if they don’t use github)</p>
|
||
|
||
<p>A <code class="highlighter-rouge">for</code> loop on this with a list of every team number did the trick for finding accounts.</p>
|
||
|
||
<h3 id="fetching-language-info">Fetching language info</h3>
|
||
<p>To remove the need for an Oauth login to use the script, GitHub data is retrieved using standard HTTPS requests instead of AJAX requests to the API. This gets around the tiny rate limit, but takes a bit longer to complete.</p>
|
||
|
||
<p>To check for language usage, a simple Regex pattern can be used: <code class="highlighter-rouge">/programmingLanguage"\&gt;(.*)\&lt;/gm</code></p>
|
||
|
||
<p>When combined with an <code class="highlighter-rouge">re.findall()</code>, this pattern will return a list of all recent languages used by a team.</p>
|
||
|
||
<h3 id="data-saves--backup-solution">Data saves / backup solution</h3>
|
||
<p>To deal with the fact that large amounts of data are being requested, and people might want to pause the script, I have created a system to allow for “savestates”.</p>
|
||
|
||
<p>On launch of the script, it will check for a <code class="highlighter-rouge">./data.json</code> file. If this does not exist, one will be created. Otherwise, the contents will be read. This file contains both all the saved data, and some counters.</p>
|
||
|
||
<p>Each stage of the script contains a counter, and will increment the counter every time a team has been processed. This way, if the script is stopped and restarted, the parsers will just keep working from where they left off. This was very helpful when writing the script as, I needed to stop and start it every time I needed to implement a new feature.</p>
|
||
|
||
<p>All parsing data is saved to the json file every time the script completes, or it detects a <code class="highlighter-rouge">SIGKILL</code>.</p>
|
||
|
||
<h2 id="what-i-learned">What I learned</h2>
|
||
<p>After letting the script run for about an hour, I got a bunch of data from every registered team.</p>
|
||
|
||
<p>This data includes every project (both on and offseason) from each team, so teams that build t-shirt cannons using the CTRE HERO, would have C# in their list of languages. Things like that.</p>
|
||
|
||
<p>Unsurprisingly, by far the most popular programming language is Java, with 3232 projects. These projects where all mostly, or entirely written in Java. Next up, we have C++ with 725 projects, and Python with 468 projects.</p>
|
||
|
||
<p>After Java, C++, and Python, we start running in to languages used for dashboards, design, lessons, and offseason projects. Before I get to everything else, here is the usage of the rest of the valid languages for FRC robots:</p>
|
||
<ul>
|
||
<li>C (128)</li>
|
||
<li>LabView (153)</li>
|
||
<li>Kotlin (96)</li>
|
||
<li>Rust (4)</li>
|
||
</ul>
|
||
|
||
<p>Now, the rest of the languages below Python:</p>
|
||
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>295 occurrences of JavaScript
|
||
153 occurrences of LabVIEW
|
||
128 occurrences of C
|
||
96 occurrences of Kotlin
|
||
72 occurrences of Arduino
|
||
71 occurrences of C#
|
||
69 occurrences of CSS
|
||
54 occurrences of PHP
|
||
40 occurrences of Shell
|
||
34 occurrences of Ruby
|
||
16 occurrences of Swift
|
||
16 occurrences of Jupyter Notebook
|
||
15 occurrences of Scala
|
||
12 occurrences of D
|
||
12 occurrences of TypeScript
|
||
9 occurrences of Dart
|
||
8 occurrences of Processing
|
||
7 occurrences of CoffeeScript
|
||
6 occurrences of Go
|
||
6 occurrences of Groovy
|
||
6 occurrences of Objective-C
|
||
4 occurrences of Rust
|
||
3 occurrences of MATLAB
|
||
3 occurrences of R
|
||
1 occurrences of Visual Basic
|
||
1 occurrences of Clojure
|
||
1 occurrences of Cuda
|
||
</code></pre></div></div>
|
||
|
||
<p>I have removed markup and shell languages from that list because most of them are probably auto-generated.</p>
|
||
|
||
<p>In terms of github account names, 133 teams follow FRC convention and use a username starting with <code class="highlighter-rouge">frc</code>, followed by their team number, 95 teams use <code class="highlighter-rouge">team</code> then their number, and 264 teams use something else.</p>
|
||
|
||
<h2 id="using-the-script">Using the script</h2>
|
||
<p>This script is not on PYPI this time. You can obtain a copy from my GitHub repo: <a href="https://github.com/Ewpratten/frc-code-stats">https://github.com/Ewpratten/frc-code-stats</a></p>
|
||
|
||
<p>First, make sure both <code class="highlighter-rouge">python3.7</code> and <code class="highlighter-rouge">python3-pip</code> are installed on your computer. Next, delete the <code class="highlighter-rouge">data.json</code> file. Then, install the requirements with <code class="highlighter-rouge">pip3 install -r requirements.txt</code>. Finally, run with <code class="highlighter-rouge">python3 main.py</code> to start the script. Now, go outside and enjoy nature for about an hour, and your data should be loaded!.</p></content><author><name></name></author><summary type="html">I was curious about the most used languages for FRC, so I build a Python script to find out what they where.</summary></entry><entry><title type="html">devDNS</title><link href="http://0.0.0.0:4000/blog/2019/07/01/devdns" rel="alternate" type="text/html" title="devDNS" /><published>2019-07-01T18:13:00-04:00</published><updated>2019-07-01T18:13:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/07/01/devDNS</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/07/01/devdns"><p>Over the past year and a half, I have been hacking my way around the undocumented <a href="https://devrant.com">devRant</a> auth/write API. At the request of devRant’s creators, this API must not be documented due to the way logins work on the platform. That is besides the point. I have been working on a little project called <a href="https://devrant.com/collabs/2163502">devDNS</a> over the past few days that uses this undocumented API. Why must I be so bad at writing intros?</p>
|
||
|
||
<h2 id="what-is-devdns">What is devDNS</h2>
|
||
<p>devDNS is a devRant bot written in python. It will serve any valid DNS query from any user on the platform. A query is just a comment in one of the following forms:</p>
|
||
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>@devDNS example.com
|
||
</code></pre></div></div>
|
||
<p>or</p>
|
||
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>@devDNS MX example.com
|
||
</code></pre></div></div>
|
||
<p>Of course, <code class="highlighter-rouge">MX</code> and <code class="highlighter-rouge">example.com</code> are to be replaced with the domain and entry of your choosing.</p>
|
||
|
||
<p>devDNS was inspired by <a href="https://twitter.com/1111resolver">@1111Resolver</a>, and the source is available on <a href="https://github.com/Ewpratten/devDNS">GitHub</a>.</p>
|
||
|
||
<h2 id="how-it-works">How it works</h2>
|
||
<p>The Python script behind devDNS is very simple. devDNS does the following every 10 seconds:</p>
|
||
<ul>
|
||
<li>Fetch all new notifs</li>
|
||
<li>Find only mentions</li>
|
||
<li>Spin off a thread for each mention that passes a basic parser (Is the message 2 or 3 words long)</li>
|
||
<li>In the thread, check if the message is a control message (allows me to view the status of the bot via devRant)</li>
|
||
<li>Check if the request matches a required pattern</li>
|
||
<li>Call <code class="highlighter-rouge">dnspython</code> with requested record and domain</li>
|
||
<li>Receive answer from a custom <a href="https://pi-hole.net/">PIHole</a> server with caching and super low latency</li>
|
||
<li>Send a comment with the results to the requester</li>
|
||
</ul>
|
||
|
||
<p>Thats it! Super simple, and only two days from concept to reality.</p>
|
||
|
||
<h2 id="where-is-this-hosted">Where is this hosted?</h2>
|
||
<p>This program is hosted on a raspberry pi laying in my room running docker. I also have <a href="https://www.portainer.io/">Portainer</a> set up so I can easily monitor the bot from my phone over my VPN.</p></content><author><name></name></author><summary type="html">Over the past year and a half, I have been hacking my way around the undocumented devRant auth/write API. At the request of devRant’s creators, this API must not be documented due to the way logins work on the platform. That is besides the point. I have been working on a little project called devDNS over the past few days that uses this undocumented API. Why must I be so bad at writing intros?</summary></entry><entry><title type="html">I had some fun with a router</title><link href="http://0.0.0.0:4000/blog/2019/06/27/pwnlink" rel="alternate" type="text/html" title="I had some fun with a router" /><published>2019-06-27T13:16:00-04:00</published><updated>2019-06-27T13:16:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/27/PWNlink</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/27/pwnlink"><p>I was playing around with some D-link routers today and remembered an <a href="https://www.exploit-db.com/exploits/33520">ExploitDB Entry</a> I read a while ago. Many D-link routers have a great feature that allows remote management and configuration queries. Interestingly, this cannot be disabled, and one of the pages contains a cleartext version of the admin password (yay!).</p>
|
||
|
||
<h2 id="how-to-get-yourself-an-admin-password">How to get yourself an admin password</h2>
|
||
<p>On any supported router, make an HTTP request to <code class="highlighter-rouge">http://your.router.ip.addr/tools_admin.asp/</code>. This will return a pretty large XML file containing information about your router’s hardware and configuration.</p>
|
||
|
||
<p>Notice the fact that you did not have to log in. This is due to the fact that this file seems to be used by a remote management service of some sort.</p>
|
||
|
||
<p>The important thing to note here is that, when parsed with the regex pattern: <code class="highlighter-rouge">name="user_password_tmp" value="(.*)"&gt;</code>, you get a single string. This string is the admin password of the device.</p>
|
||
|
||
<h2 id="supported-routers">Supported routers</h2>
|
||
<p>This is supported by many D-link routers. The ones I know about are:</p>
|
||
<ul>
|
||
<li>DIR-835</li>
|
||
<li>DIR-855L</li>
|
||
<li>DGL-5500</li>
|
||
</ul>
|
||
|
||
<p>Some routers have this XML file, but it is restricted… By a user without a password. These are:</p>
|
||
<ul>
|
||
<li>DHP-1565</li>
|
||
<li>DIR-652</li>
|
||
</ul>
|
||
|
||
<h2 id="pwnlink">PWNlink</h2>
|
||
<p>Like everything I play with, I made a script to do this all for me (and spent a large amount of time adding colours to the text).</p>
|
||
|
||
<p>My script is called PWNlink (PWN + D-link), It automatically finds a router on your network by looking for a specific DNS entry created by many D-link routers, then checking your gateway. Next, PWNlink reads you router’s <code class="highlighter-rouge">hnap1</code> config to find it’s model number. If supported, the script will read and parse the appropriate configs to give you the admin credentials for your router.</p>
|
||
|
||
<p>PWNlink can be installed on any *nix computer that has both <code class="highlighter-rouge">python3.7</code> and <code class="highlighter-rouge">python3-pip</code> installed. To install PWNlink, run:</p>
|
||
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>pip3 install pwnlink
|
||
</code></pre></div></div>
|
||
|
||
<p>Run the script without any arguments for automatic detection, or pass any IP address to use manual detection.</p>
|
||
|
||
<h2 id="disclamier-thingy">Disclamier thingy</h2>
|
||
<p>I don’t see much point to these, but I should probably put one anyways.</p>
|
||
|
||
<p><strong>Don’t be dumb with this script.</strong></p>
|
||
|
||
<p>I have only used it on my own (or 5024’s) routers, and did not create PWNlink with any malicious intent.</p></content><author><name></name></author><category term="projects" /><summary type="html">I was playing around with some D-link routers today and remembered an ExploitDB Entry I read a while ago. Many D-link routers have a great feature that allows remote management and configuration queries. Interestingly, this cannot be disabled, and one of the pages contains a cleartext version of the admin password (yay!).</summary></entry><entry><title type="html">Hunting snakes with a shotgun</title><link href="http://0.0.0.0:4000/blog/2019/06/27/python" rel="alternate" type="text/html" title="Hunting snakes with a shotgun" /><published>2019-06-27T03:00:00-04:00</published><updated>2019-06-27T03:00:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/27/Python</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/27/python"><p>A rather large number of people know me as “the guy who does weird things with python”. I would object to this title, but it is quite accurate. So, here are some of the things I like playing with in python. None of these are actually breaking the language, just little known facts and syntax. At some point I will share about actually breaking the language. For now, enjoy the weird things I have found over the past 6 years.</p>
|
||
|
||
<h2 id="type-hints">Type hints</h2>
|
||
<p>A little known feature of python is called “type hinting” (PEP 484). This is actually quite common to see in standard libraries, and has it’s own special syntax:</p>
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c1"># Here is a regular function
|
||
</span><span class="k">def</span> <span class="nf">meep</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="n">a</span><span class="o">*</span><span class="n">b</span><span class="o">^</span><span class="mi">2</span>
|
||
|
||
<span class="c1"># This function has no real reason to exsist, and is lacking any sort of documentation.
|
||
# Let's add a docstring to explain what it does
|
||
</span>
|
||
<span class="k">def</span> <span class="nf">meep</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="n">b</span><span class="p">):</span>
|
||
<span class="s">""" This function returns the result of a times b squared """</span>
|
||
<span class="k">return</span> <span class="n">a</span><span class="o">*</span><span class="n">b</span><span class="o">^</span><span class="mi">2</span>
|
||
|
||
<span class="c1"># Ok. The docstring explains the function, but is not too helpful
|
||
# what are a and b? what does this return?
|
||
# For all we know, a could actually be a string (in which case, this function would return a string)
|
||
# Let's fix that up with a type hint
|
||
</span>
|
||
<span class="k">def</span> <span class="nf">meep</span><span class="p">(</span><span class="n">a</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">b</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span>
|
||
<span class="s">""" This function returns the result of a times b squared """</span>
|
||
<span class="k">return</span> <span class="n">a</span><span class="o">*</span><span class="n">b</span><span class="o">^</span><span class="mi">2</span>
|
||
|
||
<span class="c1"># Thanks to the :int (called a type hint in case you didn't notice that yet), we now know that this function expects two ints.
|
||
# Now, to finish this up with a secondary type hint to specify the return type
|
||
</span><span class="k">def</span> <span class="nf">meep</span><span class="p">(</span><span class="n">a</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">b</span><span class="p">:</span> <span class="nb">int</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nb">int</span><span class="p">:</span>
|
||
<span class="s">""" This function returns the result of a times b squared """</span>
|
||
<span class="k">return</span> <span class="n">a</span><span class="o">*</span><span class="n">b</span><span class="o">^</span><span class="mi">2</span>
|
||
|
||
<span class="c1"># There. Now we can clearly see that this function takes too ints, and returns one int.
|
||
# If only this was a requirement in the language. So many headaches could be solved.
|
||
</span></code></pre></div></div>
|
||
|
||
<p>Now, keep in mind that this is called a type <em>hint</em>. The python compiler (yes.. Give me a second for that one) does not actually care if you obey the hint or not. Feel free to send incorrect data into a hinted function and see what you can break. Critical functions should both hint and check the data types being provided.</p>
|
||
|
||
<h2 id="type-declarations">Type declarations</h2>
|
||
<p>Just like type hints for functions, python has hints for variables too.</p>
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c1"># A regular variable. Must be declared with an initial value
|
||
</span><span class="n">my_state</span> <span class="o">=</span> <span class="bp">None</span>
|
||
|
||
<span class="c1"># my_state is None, as it has not been set, but needs to exist.
|
||
# Let's assume that my_state is to be a state:
|
||
</span><span class="k">class</span> <span class="nc">State</span><span class="p">:</span>
|
||
<span class="n">status</span> <span class="o">=</span> <span class="bp">False</span>
|
||
<span class="k">def</span> <span class="nf">toggle</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">status</span> <span class="o">!=</span> <span class="bp">self</span><span class="o">.</span><span class="n">status</span>
|
||
|
||
<span class="c1"># Finally, its time to set the state to something useful
|
||
</span><span class="n">my_state</span> <span class="o">=</span> <span class="n">State</span><span class="p">()</span>
|
||
<span class="n">my_state</span><span class="o">.</span><span class="n">toggle</span><span class="p">()</span>
|
||
|
||
<span class="c1"># Ok.. I hate this. Let's start by using type declarations first
|
||
# Any variable can be un-initialized and just have a type. Like so:
|
||
</span><span class="n">my_state</span><span class="p">:</span> <span class="n">State</span>
|
||
|
||
<span class="c1"># This works for anything
|
||
</span><span class="n">is_alive</span><span class="p">:</span> <span class="nb">bool</span>
|
||
<span class="n">age</span><span class="p">:</span> <span class="nb">int</span>
|
||
<span class="n">name</span><span class="p">:</span> <span class="nb">str</span>
|
||
|
||
<span class="c1"># Now, with this new knowledge, let's rewrite State
|
||
</span><span class="k">class</span> <span class="nc">State</span><span class="p">:</span>
|
||
<span class="n">status</span><span class="p">:</span> <span class="nb">bool</span>
|
||
<span class="k">def</span> <span class="nf">toggle</span><span class="p">(</span><span class="bp">self</span><span class="p">:</span> <span class="n">State</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="bp">None</span><span class="p">:</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">status</span> <span class="o">!=</span> <span class="bp">self</span><span class="o">.</span><span class="n">status</span>
|
||
|
||
<span class="c1"># And initialize my_state with slightly different syntax
|
||
</span><span class="n">my_state</span> <span class="o">=</span> <span class="n">State</span><span class="p">(</span><span class="n">status</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>I have not found much use for this yet. Hopefully there is something cool to use it for.</p>
|
||
|
||
<h2 id="one-line-functions">One-line functions</h2>
|
||
<p>This is more common knowlage. A function can be declared in one line</p>
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c1"># Here is an adder function
|
||
</span><span class="k">def</span> <span class="nf">adder1</span><span class="p">(</span><span class="n">a</span><span class="p">:</span><span class="nb">int</span><span class="p">,</span> <span class="n">b</span><span class="p">:</span><span class="nb">int</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="nb">int</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">a</span><span class="o">+</span><span class="n">b</span>
|
||
|
||
<span class="c1"># Here is a one-line adder function
|
||
</span><span class="n">adder2</span> <span class="o">=</span> <span class="k">lambda</span> <span class="n">a</span><span class="p">,</span><span class="n">b</span> <span class="p">:</span> <span class="n">a</span><span class="o">+</span><span class="n">b</span>
|
||
|
||
<span class="c1"># State from above can be compacted further:
|
||
</span><span class="k">class</span> <span class="nc">State</span><span class="p">:</span>
|
||
<span class="n">status</span><span class="p">:</span> <span class="nb">bool</span>
|
||
<span class="n">toggle</span> <span class="o">=</span> <span class="k">lambda</span> <span class="bp">self</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">status</span> <span class="o">!=</span> <span class="bp">self</span><span class="o">.</span><span class="n">status</span>
|
||
</code></pre></div></div>
|
||
|
||
<h2 id="ternary-operations">Ternary operations</h2>
|
||
<p>On the trend of one-line code, We have the one-line if/else, also known as a Ternary in more sensible languages.</p>
|
||
<div class="language-python highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c1"># Here is an if/else
|
||
</span><span class="k">if</span> <span class="mi">100</span> <span class="ow">is</span> <span class="mi">5</span><span class="p">:</span>
|
||
<span class="k">print</span><span class="p">(</span><span class="s">"The world has ended"</span><span class="p">)</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">print</span><span class="p">(</span><span class="s">"All is good"</span><span class="p">)</span>
|
||
|
||
<span class="c1"># Here is a smaller if/else
|
||
</span><span class="k">print</span><span class="p">(</span><span class="s">"The world has ended"</span> <span class="k">if</span> <span class="mi">100</span> <span class="ow">is</span> <span class="mi">5</span> <span class="k">else</span> <span class="s">"All is good"</span><span class="p">)</span>
|
||
</code></pre></div></div>
|
||
|
||
<h2 id="compiled-python">Compiled python</h2>
|
||
<p>This one is interesting. Python, like Java, is compiled into bytecode. So yes, it technically is a compiled language. To see said bytecode, take a look at any <code class="highlighter-rouge">.pyc</code> file sitting in your <code class="highlighter-rouge">__pycache__</code></p>
|
||
|
||
<h2 id="blog-formatting-experiments">Blog formatting experiments</h2>
|
||
<p>I am still playing with post formats, and various types of content. This is more random than I usually prefer. Let me know your thoughts on the social media platform of your choosing.</p></content><author><name></name></author><summary type="html">A rather large number of people know me as “the guy who does weird things with python”. I would object to this title, but it is quite accurate. So, here are some of the things I like playing with in python. None of these are actually breaking the language, just little known facts and syntax. At some point I will share about actually breaking the language. For now, enjoy the weird things I have found over the past 6 years.</summary></entry><entry><title type="html">BashSmash</title><link href="http://0.0.0.0:4000/blog/2019/06/26/bashsmash" rel="alternate" type="text/html" title="BashSmash" /><published>2019-06-26T11:48:00-04:00</published><updated>2019-06-26T11:48:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/26/BashSmash</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/26/bashsmash"><p>I was watching this great <a href="https://www.google.com/url?sa=t&amp;rct=j&amp;q=&amp;esrc=s&amp;source=web&amp;cd=1&amp;cad=rja&amp;uact=8&amp;ved=2ahUKEwiOhNze_4fjAhUiB50JHR12D8AQwqsBMAB6BAgJEAQ&amp;url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D6D1LnMj0Yt0&amp;usg=AOvVaw2nOgft0SoPZujc9js9Vxhx">Liveoverflow video</a> yesterday, and really liked the idea of building escape sequences with strings. So, I built a new tool, <a href="https://pypi.org/project/bashsmash/">BashSmash</a>.</p>
|
||
|
||
<h2 id="the-goal">The goal</h2>
|
||
<p>The goal of BashSmash is very similar to that described in Liveoverflow’s video. Do anything in bash without using any letters or numbers except <code class="highlighter-rouge">n</code> and <code class="highlighter-rouge">f</code> (he used <code class="highlighter-rouge">i</code> instead of <code class="highlighter-rouge">f</code>). This can both bypass shell injection filters, and generally mess with people.</p>
|
||
|
||
<p>Saying “Hey, you should run:”</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code>__<span class="o">()</span> <span class="o">{</span>/???/???/???n?f <span class="k">${#}</span><span class="p">;</span><span class="o">}</span><span class="p">;</span> <span class="si">$(</span>/???/???/???n?f <span class="si">$(</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span><span class="si">)</span><span class="p">;</span><span class="si">)</span><span class="p">;</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Instead of:</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nb">sudo rm</span> <span class="nt">-rf</span> <span class="nt">--no-preserve--root</span> /
|
||
</code></pre></div></div>
|
||
|
||
<p>Can usually get you much farther with your goal of world domination.</p>
|
||
|
||
<h2 id="how-does-this-work">How does this work?</h2>
|
||
<p>BashSmash abuses bash wildcards, octal escape codes, and a large number of backslashes to obfuscate any valid shell script.</p>
|
||
|
||
<p>Firstly, it is important to know that <code class="highlighter-rouge">printf</code> will gladly convert any octal to a string, and bash’s eval (<code class="highlighter-rouge">$()</code>) function will gladly run any string as a bash script. (See where this is going?)</p>
|
||
|
||
<p>Because of these tools, we know that the following is possible:</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c"># Printf-ing a string will print the string</span>
|
||
<span class="nb">printf</span> <span class="s2">"hello"</span> <span class="c"># This will return hello</span>
|
||
|
||
<span class="c"># Printf-ing a sequence of octal escapes will also print a string</span>
|
||
<span class="nb">printf</span> <span class="s2">"</span><span class="se">\1</span><span class="s2">50</span><span class="se">\1</span><span class="s2">45</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">57"</span> <span class="c"># This will also return hello</span>
|
||
|
||
<span class="c"># Eval-ing a printf of an octal escape sequence will build a string, then run it in bash</span>
|
||
<span class="si">$(</span><span class="nb">printf</span> <span class="s2">"</span><span class="se">\1</span><span class="s2">50</span><span class="se">\1</span><span class="s2">45</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">57"</span><span class="si">)</span> <span class="c"># This will warn that "hello" is not a valid command</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>This has some issues. You may have noticed that letters are required to spell <code class="highlighter-rouge">printf</code>, and numbers are needed for the octal escapes. Let’s start by fixing the letters problem.</p>
|
||
|
||
<p>Bash allows wildcards. You may have run something like <code class="highlighter-rouge">cp ./foo/* ./bar</code> before. This uses the wildcard <code class="highlighter-rouge">*</code>. The <code class="highlighter-rouge">*</code> wildcard will be auto-evaluated to expand into a list of all files in it’s place.</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c"># Let's assume that ./foo contains the following files:</span>
|
||
<span class="c"># john.txt</span>
|
||
<span class="c"># carl.txt</span>
|
||
|
||
<span class="c"># Running the following:</span>
|
||
<span class="nb">cat</span> ./foo/<span class="k">*</span>
|
||
|
||
<span class="c"># Will automatically expand to:</span>
|
||
<span class="nb">cat</span> ./foo/john.txt ./foo/carl.txt
|
||
|
||
<span class="c"># Now, lets assume that ./baz contains a single file:</span>
|
||
<span class="c"># KillHumans.sh</span>
|
||
|
||
<span class="c"># Running:</span>
|
||
./baz/<span class="k">*</span>
|
||
|
||
<span class="c"># Will execute KillHumans.sh</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Neat, Right? To take this a step further, you can use the second wildcard, <code class="highlighter-rouge">?</code>, to specify the number of characters you want to look for. Running <code class="highlighter-rouge">./baz/?</code> will not run <code class="highlighter-rouge">KillHumans.sh</code> because <code class="highlighter-rouge">KillHumans.sh</code> is not 1 char long. But <code class="highlighter-rouge">./baz/?????????????</code> will. This is messy, but it works.</p>
|
||
|
||
<p>Now, back to our problem with <code class="highlighter-rouge">printf</code>. <code class="highlighter-rouge">printf</code> is located in <code class="highlighter-rouge">/usr/bin/printf</code> on all *nix systems. This is handy as, firstly, this can be wildcarded, and secondly, the path contains 2 <code class="highlighter-rouge">n</code>’s and an <code class="highlighter-rouge">f</code> (the two letters we are allowed to use). So, instead of calling <code class="highlighter-rouge">printf</code>, we can call <code class="highlighter-rouge">/???/??n/???n?f</code>.</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c"># Now, we can call:</span>
|
||
/???/??n/???n?f <span class="s2">"</span><span class="se">\1</span><span class="s2">50</span><span class="se">\1</span><span class="s2">45</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">57"</span>
|
||
|
||
<span class="c"># To print "hello". Or:</span>
|
||
<span class="si">$(</span>/???/??n/???n?f <span class="s2">"</span><span class="se">\1</span><span class="s2">50</span><span class="se">\1</span><span class="s2">45</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">54</span><span class="se">\1</span><span class="s2">57"</span><span class="si">)</span>
|
||
|
||
<span class="c"># To run "hello" as a program (still gives an error)</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Now, our problem with letters is solved, but we are still using numbers.</p>
|
||
|
||
<p>Bash allows anyone to define functions. These functions can take arguments and call other programs. So, what if we have a function that can take any number of arguments, and return the number of arguments as a number? This will be helpful because an empty argument can be added with <code class="highlighter-rouge">""</code> (not a number or letter), and this will replace the need for numbers in our code. On a side note, bash allows <code class="highlighter-rouge">__</code> as a function name, so that’s cool.</p>
|
||
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c"># Our function needs to do the following:</span>
|
||
<span class="c"># - Take any number of arguments</span>
|
||
<span class="c"># - Turn the number to a string</span>
|
||
<span class="c"># - Print the string so it can be evaluated back to a number with $()</span>
|
||
|
||
<span class="c"># First, we start with an empty function, named __ (two underscores)</span>
|
||
__<span class="o">()</span> <span class="o">{}</span><span class="p">;</span>
|
||
|
||
<span class="c"># Easy. Next, we use a built-in feature of bash to count the number of arguments passed</span>
|
||
__<span class="o">()</span> <span class="o">{</span> <span class="k">${#}</span> <span class="o">}</span><span class="p">;</span>
|
||
|
||
<span class="c"># With the ${#} feature in bash, giving this function 3 arguments will return a 3</span>
|
||
<span class="c"># Next, we need to print this number to stdout </span>
|
||
<span class="c"># This can be done with printf</span>
|
||
<span class="c"># We still do not want to use any letters or numbers, so we must use our string of wildcards</span>
|
||
/???/??n/???n?f
|
||
|
||
<span class="c"># So, we just plug this into our function</span>
|
||
__<span class="o">()</span> <span class="o">{</span>/???/??n/???n?f <span class="k">${#}</span><span class="o">}</span><span class="p">;</span>
|
||
|
||
<span class="c"># Now, calling our function with three arguments</span>
|
||
__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span>
|
||
<span class="c"># Will print:</span>
|
||
3
|
||
</code></pre></div></div>
|
||
|
||
<p>Let’s put this together. First, we must tell bash that our <code class="highlighter-rouge">__</code> function exists.</p>
|
||
<div class="language-bash highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="c"># We do this by starting our new script with: </span>
|
||
__<span class="o">()</span> <span class="o">{</span>/???/??n/???n?f <span class="k">${#}</span><span class="o">}</span><span class="p">;</span>
|
||
|
||
<span class="c"># Next, an eval to actually run our constructed string. Together it now looks like this:</span>
|
||
__<span class="o">()</span> <span class="o">{</span>/???/??n/???n?f <span class="k">${#}</span><span class="o">)</span><span class="p">;</span> <span class="si">$(</span>/???/??n/???n?f <span class="si">)</span>
|
||
|
||
<span class="c"># Now, we construct a string using the __ function over and over again. "echo hello" looks like:</span>
|
||
__<span class="o">()</span> <span class="o">{</span>/???/???/???n?f <span class="k">${#}</span><span class="p">;</span><span class="o">}</span><span class="p">;</span> <span class="si">$(</span>/???/???/???n?f <span class="si">$(</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span>/???/???/???n?f <span class="s2">"</span><span class="se">\\\\</span><span class="sb">`</span>__ <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">``</span>__ <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="s2">""</span> <span class="sb">`</span><span class="s2">"</span><span class="p">;</span><span class="si">)</span><span class="p">;</span><span class="si">)</span><span class="p">;</span>
|
||
</code></pre></div></div>
|
||
|
||
<p>Thats it! You do not actually have to worry about this, because BashSmash does it all for you automatically.</p>
|
||
|
||
<h2 id="how-do-i-use-the-script">How do I use the script?</h2>
|
||
<p>To use BashSmash, simply make sure both <code class="highlighter-rouge">python3.7</code> and <code class="highlighter-rouge">python3-pip</code> are installed on your computer, then run:</p>
|
||
<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>pip3 install bashsmash
|
||
</code></pre></div></div>
|
||
|
||
<p>For more info, see the <a href="https://pypi.org/project/bashsmash/">PYPI Page</a>.</p>
|
||
|
||
<h2 id="why-do-you-have-a-desire-to-break-things-with-python">Why do you have a desire to break things with python</h2>
|
||
<p>Because it is fun. Give it a try!</p>
|
||
|
||
<p>I will have a post here at some point about the weird things I do in my python code and why I do them.</p></content><author><name></name></author><category term="projects" /><summary type="html">I was watching this great Liveoverflow video yesterday, and really liked the idea of building escape sequences with strings. So, I built a new tool, BashSmash.</summary></entry><entry><title type="html">The language hunt: Part 2</title><link href="http://0.0.0.0:4000/blog/2019/06/24/languagehunt2" rel="alternate" type="text/html" title="The language hunt: Part 2" /><published>2019-06-24T17:36:00-04:00</published><updated>2019-06-24T17:36:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/24/LanguageHunt2</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/24/languagehunt2"><p>This is a very short post, just to explain the result of <a href="/frc/2019/04/30/FRC-Languages.html">The language Hunt</a>.</p>
|
||
|
||
<h2 id="our-choice">Our choice</h2>
|
||
<p>For our upcoming 2020 season and for the forseeable future, we have chosen Java as our programming language for direct hardware interfacing, and Python for networking, vision, and other smaller tasks.</p>
|
||
|
||
<h2 id="what-does-this-mean-for-the-team">What does this mean for the team?</h2>
|
||
<p>Not too much. Aside from learning new syntax, tools, and no longer worrying about linker errors, Java and C++ have no real difference. Most of the reason Java was chosen was based on support instead of functionality. Java is much better supported by FIRST, WPILib, and other vendors. Java is also taught in the school 5024 is based from. For a more detailed explanation of the benefits of each language, take a look at Chief Delphi. There are plenty of posts there explaining the choices of many teams and their reasoning.</p>
|
||
|
||
<h2 id="side-note">Side note</h2>
|
||
<p>I am experimenting with various post formats (This being a short post). Let me know which you prefer via the social platform of your choice.</p></content><author><name></name></author><summary type="html">This is a very short post, just to explain the result of The language Hunt.</summary></entry><entry><title type="html">I gave Google’s CTF a short try and learned a thing or two</title><link href="http://0.0.0.0:4000/blog/2019/06/23/googlectf" rel="alternate" type="text/html" title="I gave Google's CTF a short try and learned a thing or two" /><published>2019-06-23T18:04:00-04:00</published><updated>2019-06-23T18:04:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/23/googlectf</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/23/googlectf"><p>Honestly, I completely forgot that this was the weekend of Google’s online <a href="https://g.co/ctf">CTF Qualifications</a> for 2019 and was late, unprepared, busy, and did not have a team to work with.</p>
|
||
|
||
<h2 id="what-is-this-event">What is this event?</h2>
|
||
<p>Google hosts a (yearly?) event where hackers from around the world team up and attempt a variety of tasks like: exploiting machines over a network, reversing firmware, pulling passwords from tcp packets, hacking crypto stuff (something I suck at), breaking compilers. and much more. Generally, this event and others like it are really fun.</p>
|
||
|
||
<h2 id="what-i-learned">What I learned</h2>
|
||
<p>Many questions I worked on involved extracting a key from a binary. I employed two vastly different tools for this job. First, a standard linux tool, <code class="highlighter-rouge">strings</code>. When passed a filename, it will extract and print all human-readable strings it can find to the terminal. The flag is usually in this dump. If not, I use the second tool. <a href="https://www.nsa.gov/resources/everyone/ghidra/">Ghidra</a>, an open-source reverse engineering tool designed by the NSA. I used this tool a fair amount during my quick attempt at GCTF.</p>
|
||
|
||
<h2 id="will-i-do-this-again">Will I do this again?</h2>
|
||
<p>Yes! The CTF was very fun to try, and I will definitely give it a proper shot next time.</p></content><author><name></name></author><summary type="html">Honestly, I completely forgot that this was the weekend of Google’s online CTF Qualifications for 2019 and was late, unprepared, busy, and did not have a team to work with.</summary></entry><entry><title type="html">What I have learned from 2 years of FRC programming</title><link href="http://0.0.0.0:4000/blog/2019/06/21/robot-experiences" rel="alternate" type="text/html" title="What I have learned from 2 years of FRC programming" /><published>2019-06-21T11:14:00-04:00</published><updated>2019-06-21T11:14:00-04:00</updated><id>http://0.0.0.0:4000/blog/2019/06/21/Robot-Experiences</id><content type="html" xml:base="http://0.0.0.0:4000/blog/2019/06/21/robot-experiences"><p>Over the past two years (2018 / 2019), I have been a member of my school’s <a href="https://www.firstinspires.org/robotics/frc">FRC</a> team, <a href="frc5024.github.io">Raider Robotics</a>. Specifically, a programmer.</p>
|
||
|
||
<h2 id="my-roles">My roles</h2>
|
||
<p>In my first year, I joined the team as a programmer and had a fun time learning about embedded programming and development with hardware. Then, in my second year, I was promoted to programming co-lead along with <a href="https://github.com/slownie">@slownie</a>. I much preferred my second season because I had a better understanding of the technology I was working with, and we got to play with some cool tools throughout the season.</p>
|
||
|
||
<h2 id="what-i-have-learned">What I have learned</h2>
|
||
<p>Starting with our 2018 season, PowerUP. We learned early on that there is a practical limit to the number of programmers that 5024 can handle. That year, we had too many, and our situation was not helped by the fact that some members preferred scrolling through Instagram over writing code. This issue was almost entirely fixed by the introduction of a mandatory skill exam at the start of the season. Sam and I did not really care about the scores of the exam because, from reading the results, we could see who was actually motivated to join the team. Thanks to the test, we entered the season with seven excited programmers.</p>
|
||
|
||
<p>During the PowerUP season, I also learned the importance of student involvement. Most of the code from the season was written by mentors with the students just watching on a projecter. After talking with other team members, I learned that none of them through this was a good method of teaching, and many felt powerless. In the 2019 season, I completely reversed this. All students worked together on the codebase, and the mentors worked on other projects and provided input where needed.</p>
|
||
|
||
<h3 id="version-control">Version Control</h3>
|
||
<p>During the 2018 season, code was shared around by USB. This lead to crazy conflicts, confusion over what was running on the robot, and general frustration during competitions. In 2019, I moved the team over to a <a href="https://github.com">GitHub</a> organization account and sent an email to support to get us unlimited private repos (thanks GitHub!). For the team members that where not comfortable in the terminal, I set them up with <a href="https://www.gitkraken.com/">GitKracken PRO</a> accounts, and they enjoyed using the program. The rest of us stuck with GIT cli, or various plugins for VSCode.</p>
|
||
|
||
<h3 id="alpha-test">Alpha test</h3>
|
||
<p>I got our team on board with the 2019 toolchain alpha test the week it was released in order to get everyone used to the new tools before the season (and help find bugs for the WPILib team). The new buildsystem, Gradle, worked great and I could even run it on the chromebook I was using for development at the time! To further assist the team, I set up a CI pipeline for automatic testing and code reviews of Pull Requests, and a doxygen + GitHub pages CD pipeline for our new documentation webpage.</p>
|
||
|
||
<h3 id="webdocs">Webdocs</h3>
|
||
<p>A significant amount of my time was spent answering repetitive questions from the team. I enjoy helping people out, but explaining the same things over and over was starting to frustrate me. This was caused by a lack of documentation or bits of documentation spread over multiple websites. To solve this problem, I started the <a href="https://frc5024.github.io/webdocs/#/">Webdocs Page</a>. This website is designed to house a mix of team-specific notes, guides, low-level documentation, and documentation from all FRC vendors. This site was published after the season, so I will find out how usefull it really is during the 2020 season.</p>
|
||
|
||
<h3 id="command-base">Command base</h3>
|
||
<p>“Command based programming is great. But…” is probably the best way to describe my suggested changes for 2020.</p>
|
||
|
||
<p>I have been learning from other teams, and from mentors about better ways to control our robot. During the offseason, I am playing with new ways to write robot code. Here are some of my changes:</p>
|
||
<ul>
|
||
<li>Use a custom replacement for WPILib’s <a href="https://first.wpi.edu/FRC/roborio/release/docs/java/edu/wpi/first/wpilibj/command/Subsystem.html">Subsystem</a> that buffers it’s inputs and outputs
|
||
<ul>
|
||
<li>This reduces load on our CAN and Ethernet networks</li>
|
||
</ul>
|
||
</li>
|
||
<li>Offload all camera and vision work to a Raspberry PI</li>
|
||
<li>Every subsystem must push telemetry data to NetworkTables for easy debugging and detailed logs</li>
|
||
<li>Use a custom logging system that buffers writes to stdout. This reduces network strain</li>
|
||
</ul>
|
||
|
||
<p>I am working on many other changes over on the <a href="https://github.com/frc5024/MiniBot">MiniBot</a> codebase.</p>
|
||
|
||
<h2 id="my-plans-for-2020">My plans for 2020</h2>
|
||
<p>I have been re-selected to be the sole lead of the 5024 programming team for 2020. Here are my goals:</p>
|
||
<ul>
|
||
<li>Switch the team from C++ to Java
|
||
<ul>
|
||
<li>Easier for prototyping</li>
|
||
<li>Better memory management for high-level programmers</li>
|
||
<li>Better documentation from vendors</li>
|
||
<li>It is taught in our school’s compsci classes</li>
|
||
</ul>
|
||
</li>
|
||
<li>Remove the skills exam in favour of weekly homework for the first 8 weeks</li>
|
||
<li>Provide writeups of lessons</li>
|
||
<li>Have mentors do “guest presentations”</li>
|
||
<li>Dedicate a day to robot driving lessons</li>
|
||
<li>Use a custom library with wrappers and tools built by me to provide easy interfaces for new programmers</li>
|
||
</ul></content><author><name></name></author><summary type="html">Over the past two years (2018 / 2019), I have been a member of my school’s FRC team, Raider Robotics. Specifically, a programmer.</summary></entry></feed> |