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19340 views · 6 years ago
Creating a Virus with PHP

In his talk, “Writing Viruses for Fun, Not Profit,”Ben Dechrai (after making the viewer take a pledge to only use this knowledge for good and not evil) walks through how many viruses operate, and just how easy it is to build your own self-replicating virus in PHP.

The danger of many of these viruses according to Ben is that the most dangerous viruses often escape detection by not looking like a virus. Instead they encrypt their code to hide their true intent, while also constantly adapting and evolving.

Perhaps even more dangerously, they act like they’re benign and don’t actually do anything - often times laying dormant until called upon by the malicious actor.

Creating the Virus

What’s scary is just how simple it was for Ben to create such a virus, one that mutated ever so slightly as it infected every other file on the server. Opening up unlimited possibilities from scraping customer data, to DDOS attacks, to simply hijacking your domain.



But those attacks are just the start as Ben demonstrated how easy it is to write new files, delete files, eval() and execute foreign code - which could even be extended to accessing the underlying server itself if shell_exec() is enabled.

To add to the problem, Ben shares how challenging it can be to identify malicious code on your server as many of these attacks are far more sophisticated than the the virus he created in a matter of minutes - hiding themselves and often appearing as if they are part of the original source code.

Deploying the Virus

To drive his point home, Ben demonstrates how even seemingly secure systems can be vulnerable - as all it takes is one tiny misstep within your application.

He highlights this by building what should be a secure photo gallery - one that checks the extension and mime-type of the image - and even stores it outside of the public directory. He goes even farther by adding additional sanity checks with a PHP script that then renders the image.

After walking through the code and it’s security features, he then downloads a simple image from the internet. Opening his editor he quickly injects the virus (written in PHP) into the image and uploads it, passing all of the server checks.

Surely, since it passed these checks the system is secure, right? Ben loads the gallery to proudly show off the image - which is just that… an image, with nothing special or out of the ordinary.
Except that when he opens the image gallery files, each has been infected with the malicious code.

The culprit that allowed for Ben to hijack an entire system and execute foreign code, create new files, and even hijack the entire site? When displaying the image the file was included using PHP’s include() function, instead of pulling in the data using file_get_contents() and echoing it out.

Such a simple mistake provided Ben, if he was a malicious hacker, complete access to all of the files on the system.

Protecting Yourself

Security always exists in layers - and this could have been prevented by including a few more layers, such as using an open source library to rewrite the image, reviewing the image source before pulling it in, or again not giving it executable access by using the PHP include() function.

But what’s terrifying is how simple it is to hijack a site, how easy it is to get access to your system and private data, and how easy it is to overlook security vulnerabilities - especially with open source tooling and those that take plugins.

As Ben explains, sometimes the core code itself is really secure, but then you get two different plugins that when used together accidentally create a security vulnerability. That by itself is one of the most challenging as you can audit each plugin individually, and still not know you’re opening up your system to malicious actors.

This is why it's not just important to stay up to date on the latest security measures and best practices, but to be constantly thinking like a hacker and testing your code for vulnerabilities.

Learn More

You can watch thefull video to learn more how viruses operate, how to quickly build your own PHP virus (but you must promise to use it for good), and what to watch for in order to protect yourself, your customers, and your architecture.
10889 views · 4 years ago
Web Sockets in PHP

In his talk Websockets in PHP, John Fransler walks us through the use of WebSockets in PHP.

While discussing bi-directional real-time application development, John notes that PHP is often not invited to the table due to its lack of native support. Of all the possible attempts to bring in PHP on this stage of real-time development, Ratchet, a PHP WebSocket library, comes closest. "Ratchet is a loosely coupled PHP library providing developers with tools to create real-time, bi-directional applications between clients and servers over WebSockets."* Ahem!

Today's dynamic world


In today's dynamic content world of the internet, it is required to serve real-time bi-directional messages between clients and servers. WebSockets are simple, full-duplex, and persistent. They work over Http and are a standard today.

WebSockets have compatibility with 96.5% of clients globally

There's a very high chance your client has the necessary plumbing to access your content via WebSockets. WebSockets gives the ability to have real-time data on to your clients without the need for polling.

To understand WebSockets, John takes an example of a Javascript client and Ratchet Server. Javascript has everything built in to allow access to a socket. For example, you can use the send method on a WebSocket variable to send a message to the server, or if you want to respond to a message from the server, you use the OnConnection method.

While on the Server, John uses Ratchet, which is built on React PHP. A server script is then configured and set up to run and listen on a port for incoming HTTP requests. For messages, JSON is used, and to find public methods, a router is set up. He then goes on to instantiate the server-side script in Ratchet.

There are four functions of a Ratchets message component interface that are used in this example:

OnOpen gets called when a new connection is made.

OnClose gets called when a client quits. It's essential to keep an eye on memory management, and essential to keep tidying up as you move through the code.

OnError gets called when there is an exception faced by the user.

OnMessage gives the text of the JSON message, which is being exchanged with the client.

For Initialization, Jason continues to walk through the example. He shows how one can loop through the clients, both inside the server and outside the server. Outside the server, it’s a feature of React PHP. On database access, and with traditional standard synchronous MySQL in PHP, what usually happens is that it forces the code to wait for the query to return a result and do nothing — Fortunately, with Asynchronous MySQLi, that is not the case.

John gets into the details explaining Variables, References & Pointers. He also gives a demo where a central site has updated information on the Bitcoin and ether prices. A client terminal reflects the last values. Now the client doesn't have to poll the server for new values. When there is a change in the Bitcoin or ether values, the server pushes down the client's update. No polling helps with a lot of overheads and gets closer to real-time.

Using Supervisord


For Long-running applications - Jason recommends running a supervisord, use proxy to expose the port, and add a site certificate. Supervisord keeps an eye out for the server running the service; it can be used to restart the service and log any service issues. Recommended proxies are AWS load balancer, Nginx, and HA Proxy. For scalability, use multiple smaller WebSocket servers and a smaller number of clients per server used and load balancing. If one has to support a chat feature to allow clients to talk to each other in near real-time, it is recommended to use Redis. The Redis server proxies the messages between the server nodes.

The talk concludes with John summarizing best practices on error handling and takes QnA on various aspects of WebSockets such as handling load balancers and asynchronous calls to MSQLi.

The presentation for this video, along with the code, is hosted at John Curt's GitHub. More info about John's current areas of interest can be found on John's Blog.

Watch the video now


Related videos
10554 views · 4 years ago


Welcome back!, if you’re new please be sure to read Part 1 here.


This tutorial will focus primarily on Security and will touch on how to plan functionality.

Planning out an application and seeing progress regularly is a good strategy as you are most likely to complete your tasks in a timely fashion with this approach.

Ready?, ok let’s jump into it!

DISCLAIMER


We highly recommend that you follow these tutorials on a localhost testing server like Uniserver. Read through Part 1 here to look at our recommendations. These tutorials follow a phased approach and it is highly recommended that you do not make snippets of code live prior to completing this tutorial series.


Where we left off – the serious stuff.


In the previous tutorial we saved variables to the database.

It’s important to note that further steps are needed to ensure that data transactions to / from the database are secure.

A great first step is to ensure that all POST data (data transmitted after a user clicks a form’s submit button) is sanitized.

What we’re trying to prevent


One of the most common exploits is SQL Injection, an attack most commonly used to insert SQL into db queries. POST data that’s not sanitized leaves a huge security hole for malicious exploits. In some cases SQL injection can be leveraged to rage an all out assault on a server’s operating system.

A few examples of a basic version of what this might look like can be seen below.



OUTCOME


This might delete your database table



OUTCOME


This might provide access to the entire user table and the password protected area/dashboard.


***Please note that there are various types of SQL injection techniques and I will delve into this during the course of this series.***


So what exactly is sanitization and what does it do?


When sanitizing POST data, we are essentially looking for any special characters that are often used in SQL injection attacks.

In many ways, this tiny piece of code is the unsung superhero of many database driven applications.

Let’s secure that POST data!


Navigate to your backend folder and open index.php

Locate the following line of code:

$sql = "INSERT INTO content(title,content,author)VALUES ('".$_POST["title"]."', '".$_POST["content"]."', '".$_POST["author"]."')";


Ok, let’s get to work.

Based on what I mentioned a few moments ago, it’s clear that our SQL statement is vulnerable so we need to sanitize the POST data pronto!

The method I will focus on first is $mysqli->real_escape_string. This will escape any special characters found in the POST data.

Add the following just above your $sql.

$title = $letsconnect -> real_escape_string($_POST['title']);

$content = $letsconnect -> real_escape_string($_POST['content']);

$author = $letsconnect -> real_escape_string($_POST['author']);


Did you notice the use of $letsconnect? This was used because of our db connection defined in conn.php.

Our new query will look like this:

$sql = "INSERT INTO content (title,content,author) VALUES ('".$title."', '".$content."', '".$author."')";


Go ahead and replace the old $sql.

Phew!, we can breathe easy now.

Next, let’s lighten things up a bit by focusing on functionality and aesthetics.


A phased approach is the best way to tackle projects of any size.

I tend to jot this down on paper before creating a more legible professional spec!.

Typically the phased approach lends itself to logical progression.

For example, over the next several days I will go over the following:

* Account Access
* The login process
* The registration process
* The password recovery process
* Frontend
* The look and feel
* Menus
* Sidebars
*Main Content
*Footer
* Backend
* Content Management
* Add/Edit/Delete
* Security

This will give us a good springboard to delve into more complex functionality.

The aesthetic I have in mind will be barebones at first with clean CSS practices (this will make life a whole lot easier when we have to make changes down the line!).

Challenge :


Plan out your own CMS, think about the user interface and design choices you’d like to implement, and create a phased approach.

Conclusion


I hope this tutorial encouraged you to think about security and understand one of the most common exploits. During the course of this series, you will receive the tools necessary to beef up security while maintaining your sanity!

Next up


CodeWithMe – Let’s go templating.
10237 views · 5 years ago
Conferences are always looking for speakers - it can be hard to keep track of them all and the requirements they have. I wanted to put together this quick guide to make it easy for you to apply. Make sure to apply because as Wayne Gretzky said “You miss 100% of the shots you don’t take”!!!

phpDay 2019

First we have phpDay 2019 which will take place on May 10 & 11 at Hotel San Marco in Verona, Italy. Some facts about this call for papers:
*Submission deadline: February 4, 2019
*Submit via: https://cfp.phpday.it/
* For more info on the conference: https://2019.phpday.it/
* Twitter: (@phpday)
* Speaker package includes: Full conference pass (jsDay + phpDay), speaker dinner the first night, lunch, reception and activities included in regular conference.
* For speakers remote to the Area: A refund of up to €200 for travel costs (or €500 from US or extra-EU), 2 complimentary hotel nights (+1 hotel night for speakers presenting multiple talks or US/extra-EU) and Taxi fare from/to the airport.
*In Submission: make sure your talk title and abstract define the exact topic you want to talk about and what you hope people will learn from the session.
*Talk Ideas: APIs (REST, SOAP, etc.), Architectures, Continuous Delivery, Databases, Development, Devops, Frameworks, Internals, PHP 7.x / PHP 8, Security, Testing and UI/UX.

ScotlandPHP

Next we have ScotlandPHP which will take place on November 8 & 9 at Edinburgh International Conference Centre in Edinburgh, Scotland.
*Submission deadline: April 22, 2019
*Submit via: https://cfs.scotlandphp.co.uk/
* For more info on the conference: https://conference.scotlandphp.co.uk/
* Twitter: (@scotlandphp)
* Speaker package: Full conference pass, lunch, receptions and activities included in regular conference.
* For speakers remote to the Area: Complimentary airfare/travel, 2 complimentary hotel nights and we'll pick you up and drop you off to/from the airport so you don't have to worry about it.
* Speakers will be provided with a projector, a wireless lapel microphone and a screen for their presentation (size depends on the room). Speakers should bring any equipment they need to connect to projectors (VGA). It is also suggested that you reduce your dependency on the in-house internet connection as possible. We will however provide HDMI and Mini Display Port connections for all speakers on request. If you need something different or your selected talk needs audio equipment just let us know. We'll work it out.
* Looking for talks and workshops (November 8th).
*Talk Ideas: Virtualization and environments, Javascript, Alternate PHP run-times, PHP internals, Development principles, Security, Mobile-first design, Testing (unit, functional, etc.), Version control, User Experience/Usability, Building APIs (REST, SOAP, whatever), Continuous Integration, Framework-related topics, and Professional development.

Global diversity CFP day

In 2019 there will be numerous workshops hosted around the globe encouraging and advising newbie speakers to put together your very first talk proposal and share your own individual perspective on any subject of interest to people in tech.
* Twitter: (@gdcfpday)
*Save the Date: March 2, 2019
*Register here: https://www.globaldiversitycfpday.com/?utm_source=scotphp

CoderCruise

Then there is CoderCruise which will take place on August 19-23. It's a cruise that takes off from Port Canaveral, Florida and goes to the Bahamas.
* Twitter: (@codercruise)
*Submission deadline: March 3, 2019
*Submit via: https://www.papercall.io/codercruise-2019
* For more info on the conference: https://www.codercruise.com/
* This is a polyglot conference so looking for speakers on a wide variety of languages (PHP, JavaScript, Java, Python, etc.) and on various tech topics.

PHP Conference Asia 2019

There is also PHP Conference Asia 2019, which will take place on June 24-25 at Microsot Singapore.
*Submission deadline: March 8, 2019
*Submit via: https://cfp.phpconf.asia/
* For more info on the conference: https://2019.phpconf.asia/
* Twitter: (@PHPConfAsia)
* Speaker package includes: Speaker package: Full conference pass, lunch, receptions and activities included in regular conference. We'll pick you up and drop you off to/from the airport so you don't have to worry about it. Speakers' dinner on the first evening of the conference (24th June 2019). Transport to and from the conference venue will be included
* For speakers remote to the Area: 2 complimentary hotel nights and
we can consider providing grants to partially cover the air-fare for speakers who might have financial difficulties. This is on a case-by-case basis.
* Speakers will be provided with a projector, a wireless hand-held microphone and a screen for their presentation. Speakers should prepare their slides in 4x3 aspect ratio. Speakers should bring any equipment they need to connect to projectors (HDMI). It is also suggested that you reduce your dependency on the in-house internet connection as possible.
*In Submission: Make sure your talk title and abstract define the exact topic you want to talk about and what you hope people will learn from the session.
*Talk Ideas: Virtualization and environments, Javascript, Alternate PHP run-times, PHP internals, Development principles, Security, Mobile-first design, Testing (unit, functional, etc.), Version control, User Experience/Usability, Building APIs (REST, SOAP, whatever), Continuous Integration, Framework-related topics, and Professional development.

Cascadia PHP

Another conference to apply to is Cascadia PHP, which will take place on September 19-21 at University Place Hotel & Conference Center in Portland, Oregon.
*Submission deadline: April 15, 2019
*Submit via: https://cfp.cascadiaphp.com/
* For more info on the conference: https://www.cascadiaphp.com/venue
* Twitter: (@CascadiaPHP)
* Speaker package includes: Speaker package: Full conference pass, lunch, receptions and activities included in regular conference. For speakers remote to the Area: Complimentary airfare/travel, 2 complimentary hotel nights and we'll pick you up and drop you off to/from the airport so you don't have to worry about it.
Speakers will be provided with a projector, a wireless lapel microphone and a screen for their presentation (size depends on the room). Speakers should bring any equipment they need to connect to projectors (VGA). It is also suggested that you reduce your dependency on the in-house internet connection as possible.
*In Submission: make sure your talk title and abstract define the exact topic you want to talk about and what you hope people will learn from the session.
*Talk Ideas: PHP internals, Version control, Framework-related topics, Building APIs (REST, SOAP, whatever), Mobile-first design, Professional development, Testing (unit, functional, etc.), Alternate PHP run-times, Development principles, Continuous Integration, Getting involved in the PHP community, User Experience/Usability, Technology at large, Security, Connecting to Different APIs, Development Tools, Virtualization and environments, Javascript, Modern hosting practices, Language Features, Databases, Refactoring legacy applications, Running/contributing to open source projects, AI and AR, and User Groups.

Nomad PHP

Last but not least - this is an ongoing call for papers. This is perfect if you want to present from the comfort of your office, home or really wherever you are. It’s via RingCentral meetings and will be live and recorded. This is for none other than Nomad PHP.
* Twitter: (@nomadphp)
* Deadline: Anytime :D
* Talk length: 45 - 60 minutes.
* Talks should be unique to Nomad PHP and not available in video format online.
* Talk should not be recorded or made available elsewhere online for at least 3 months following your talk.
* The talk will be featured on our page and promoted via social media.
* Speakers will receive a financial stipend.
* Upon being selected we will reach out with further details.
*Talk ideas: AI & Machine Learning, APIs, Containerization, Databases, DevOps, Documentation, Frameworks, Performance, Security, Serverless, Testing, Tools, Upgrading/ Modernization, and more.
*Submit here: https://www.papercall.io/nomadphp
Now that you have some information - make sure to apply to all of these options! Can't wait to see all of your awesome talks you present :D!
7636 views · 3 years ago
10 SEO Best Practices for Web Developers

You've built an amazing website, but how do you make sure people can find your site via search engines? In this article we cover 10 best practices to make sure your article not only stands out, but ranks well with search engines.

1. Take time to research keywords


To determine the best keywords for your site, you'll need to do some keyword research. This usually consists of combing through your competitors' sites for the keywords that are driving them the most traffic. There are several ways you can get started with keyword research. One recommended way is to create a spreadsheet with your competitors' sites listed and add keywords that you can copy and paste your competitors' keywords into Google's Keyword Tool and Google Webmaster Tools Keyword Analyzer tool. Analyze your competition's site's website titles to find out what keywords they are using tools such as Ahrefs, Moz, SpyFu, or SEMrush to find out what keywords others are using on your competitor's site.

2. Focus on your Title tag


This is the headline for every article. It needs to be bold and attention grabbing so it can catch the eye of potential users. Pick it somewhere around 60-90 characters to make sure it is displayed properly in search engines as well as readable in the browser tab. As you write your title, focus on the unique keywords your readers are likely to search for. Also make sure that the keywords you select are relevant to your page. Another good practice is to make the title tag and your header (h1) the same.

3. Carefully craft your H1, H2, H3 tags


Careful usage of header tags helps search engines identify keywords within your page. To get the best results from your header tags, use H1, H2, and H3 in order with keywords in your H2 and H3 headers that support your H1 tag. Remember, your H1 tag should mimic your title tag, whereas the H2 and H3 can expand and add additional context. You can also utilize multiple H2 and H3 tags, however be sure that these headers are supporting the H1 tag and relevant to the content on your page. Using irrelevant header keywords can actually work to your disadvantage.

4. Avoid loading content with JavaScript


Despite it's popularity, JavaScript is not yet well supported by search engines and can mask important content. Progressive Web Apps in particular can suffer as key content is loaded after the page is spidered, or in the case of many search engines that do not yet index JavaScript not loaded at all. This is also the case for many social media sites, meaning that content loaded dynamically is not evaluated or pulled in, resulting in the default skeleton of your site being what shows up in search engines and in link previews.

5. Carefully name images


In the past search engines would evaluate your images based on their alt tag, however as more and more developers loaded irrelevant keywords into this hidden image text search engines instead added more emphasis to the actual name of the image itself. This means using generic image names such as 1.jpg can actually hurt your site ranking as search engines might be looking for seokeywords.jpg. Now, just because you're carefully naming your images with relevant keywords describing the image doesn't mean you should ignore the alt tag. Be sure to continue to include alt tags for older search engines, in the case the image doesn't load, and for accessibility (ie screen readers).

6. Work to improve your page load time


It’s not a secret that faster sites rank higher in search engines. Most search engines use the PageSpeed Index from Google to determine the speed of websites. One thing Google looks at is how fast images are loading. For this reason, we recommend taking a look at how long it takes for the first image to load on your site or even take advantage of lazy loading for non-critical images. You want images to be loading within 30 seconds at the absolute latest, before the user can actually click on the page. You also need to make sure that if you're using multiple images that they load as one group. Next, take a look at how long it takes to load a webpage. Are pages taking longer than three seconds to load on your site? You want to have pages that load fast for users, but your code and templates can easily be causing this to happen.

7. Optimize text throughout your page


Beyond your title tag, headers, and images it's important to work keywords into your standard content, while also working to avoid overloading keywords. To help prevent overloading and increase search engine rankings across multiple keywords you can use alternative phrases. In the case of "PHP training" an alternative phrase might be "PHP tutorials" or "PHP course." This both helps support the primary keyword, while also allowing the page to rank for these keywords as well. Remember to use the tools referenced above to find the keywords that are right for your site, and then work them in to natural sentences without forcing keywords or becoming overly repetitive. Also keep in mind, just as important as the content and keywords on the page are to search engines, how users engage with that content is also critical. If your page experience's high bounce rates or low engagement with the content, it is likely to be deprioritized by search engines, meaning a page highly optimized for search engines but not humans may enjoy a higher ranking, but only for a short time before it is heavily penalized.

8. Build your Domain and Page Authority


Domain and Page Authority are determined not just by the number of back-links (or sites linking to your domain or page), but also the quality of the sites and pages linking to you. One practice that has made obtaining a better DA or PA harder has been purchasing or acquiring bulk back-links. Note this practice is actually against Google's TOS and may result in your entire site being banned from their search results! Because of this practice, it's important to focus on high quality sites and work to get back-links naturally either through partnerships or syndicated content (such as blog posts). You can also check your DA here or using one of the many tools referenced above.

9. Take advantage of social media


Speaking of back-links, social media can be a powerful tool for increasing page visibility while also improving your search engine rankings! Remember, most social sites do not support or read JavaScript, so ensure your content is available on the page. If you do have a progressive web app with JavaScript loading your content, look into using Headless Chrome to render a JavaScript free version of your site for specific bots (note - the content MUST be the same content a user would see or your site may be blocked). There are also numerous tools to allow you to build the content via JavaScript on the server backend before passing it to your readers. To help get even more exposure, consider adding social share links or tools like AddThis.

10. Good SEO takes time


The truth is that there really aren't any special secrets or ingredients to ranking well in search engines (well not that Google has publicly shared). Instead it's about properly formatting your page, making sure it's readable to search engines, and providing content that your readers will engage with. As you provide more valuable content, and more people like and link to your content - your site's Domain Authority will gradually increase, giving your site and pages more powerful - resulting in a higher ranking.

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