Hello Guys,

In our Last Blog Post, we have created restful apis,But not worked on its security and authentication. Login api can be public but after login apis should be authenticate using any secure token. one of them is JWT, So i am providing the Steps for Create and use JWT Token in our already created API.


Now its time To Implement JWT Authentication IN our Api, So these are the steps to implement it in our already created Apis

Step 1:Install and include Firebase JWT(JSON WEB TOKEN) in our project with following composer command        

 composer require firebase/php-jwt 

include the composer installed packages

require_once('vendor/autoload.php');

use namespace using following:

 use \Firebase\JWT\JWT; 

Step 2: Create a JWT server side using Firebase Jwt Library's encode method in Login action , and return it to Client

Define a private variable named Secret_Key in Class like following:

 private {
 $payload = array(
 'iss' => $_SERVER['HOST_NAME'],
 'exp' => time()+600, 'uId' => $UiD
 );
 try{
 $jwt = JWT::encode($payload, $this->Secret_Key,'HS256'); $res=array("status"=>true,"Token"=>$jwt);
 }catch (UnexpectedValueException $e) {
 $res=array("status"=>false,"Error"=>$e->getMessage());
 }
 return $res;
 }

In our login action , if the user has been logged in successfully then with the status,_data_ and message just replace the login success code with following code:

$return['status']=1;
$return['_data_']=$UserData[0];
$return['message']='User Logged in Successfully.';

 $jwt=$obj->generateToken($UserData[0]['id']);
 if($jwt['status']==true)
 {
 $return['JWT']=$jwt['Token'];
 }
 else{
 unset($return['_data_']);
 $return['status']=0;
 $return['message']='Error:'.$jwt['Error'];
 }

Step 3: Now with every request after login should have the JWT token in its Post(even we can receive it in get or authentication header also but here we are receiving it in post)

No afetr successfully login you will get the JWt Token in your response,Just add that Token with every post request of after login api calls. So we will do it using postman, Find the screenshot 1 for checking the JWT Token is coming in login api response

Step 4:After reciving the JWt in every after login api call, we need to check whether the token is fine using JWT decode method in After login Apis like

UserBlogs

is a After login Api, So for verify that we are creating Authencate method in class like following:

 public function Authenticate($JWT,$Curret_User_id)
 {
 try {
 $decoded = JWT::decode($JWT,$this->Secret_Key, array('HS256'));
 $payload = json_decode(json_encode($decoded),true);
 
 if($payload['uId'] == $Curret_User_id) {
 $res=array("status"=>true);
 }else{
 $res=array("status"=>false,"Error"=>"Invalid Token or Token Exipred, So Please login Again!");
 }
 }catch (UnexpectedValueException $e) {
 $res=array("status"=>false,"Error"=>$e->getMessage());
 } 
 return $res;
 
 }

Step 5: Cross check the response returned by Authenticate method in

UserBlogs

Action of api , replace the

UserBlogs

Action inner content with following code:

 if(isset($_POST['Uid']))
 {

 $resp=$obj->Authenticate($_POST['JWT'],$_POST['Uid']);
 if($resp['status']==false)
 {
 $return['status']=0;
 $return['message']='Error:'.$resp['Error'];
 }
 else{
 $blogs=$obj->get_all_blogs($_POST['Uid']);
 if(count($blogs)>0)
 {
 $return['status']=1;
 $return['_data_']=$blogs;
 $return['message']='Success.';
 }
 else
 {
 $return['status']=0;
 $return['message']='Error:Invalid UserId!';
 }
 } 
 }
 else
 {
 $return['status']=0;
 $return['message']='Error:User Id not provided!';
 }

Ah great its time to check out the UserBlogs Api, please find the screenshoot for that, Remember we need to put the JWt Token in POST Parameter as we have already recived that Value in Login Api call.



Now if you want to verify that token is expiring in given time(10 minutes after generation time/login time), i am just clicking the same api with same token after 10 minutes and you can see there will not return any data and it is returning status false with following message :





Also if you want to eloborate it more then i suggest you to try with modify Uid value with same token , you will another authentication issue and also if you modify the JWT token also then also you will not get the desired result and get authentication Issue

Thanks for reading out if you want the complete code of this file then please find following:

<?php 
header("Content-Type: application/json; charset=UTF-8");
require_once('vendor/autoload.php');
use \Firebase\JWT\JWT; 

class DBClass {

 private $host = "localhost";
 private $username = "root";
 private $password = ""; private $database = "news";

 public $connection;

 private $Secret_Key="*$%43MVKJTKMN$#"; 
 public function connect(){

 $this->connection = null;

 try{
 $this->connection = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->database, $this->username, $this->password);
 $this->connection->exec("set names utf8");
 }catch(PDOException $exception){
 echo "Error: " . $exception->getMessage();
 }

 return $this->connection;
 }

 public function login($email,$password){

 if($this->connection==null)
 {
 $this->connect();
 }
 
 $query = "SELECT id,name,email,createdAt,updatedAt from users where email= ? and password= ?";
 $stmt = $this->connection->prepare($query);
 $stmt->execute(array($email,md5($password)));
 $ret= $stmt->fetchAll(PDO::FETCH_ASSOC);
 return $ret;
 }

 public function get_all_blogs($Uid){

 if($this->connection==null)
 {
 $this->connect();
 }
 
 $query = "SELECT b.*,u.id as Uid,u.email as Uemail,u.name as Uname from blogs b join users u on u.id=b.user_id where b.user_id= ?";
 $stmt = $this->connection->prepare($query);
 $stmt->execute(array($Uid));
 $ret= $stmt->fetchAll(PDO::FETCH_ASSOC);
 return $ret;
 }

 public function response($array)
 {
 echo json_encode($array);
 exit;
 }

 public function generateToken($UiD)
 {
 $payload = array(
 'iss' => $_SERVER['HOST_NAME'],
 'exp' => time()+600, 'uId' => $UiD
 );
 try{
 $jwt = JWT::encode($payload, $this->Secret_Key,'HS256'); $res=array("status"=>true,"Token"=>$jwt);
 }catch (UnexpectedValueException $e) {
 $res=array("status"=>false,"Error"=>$e->getMessage());
 }
 return $res;
 }

 public function Authenticate($JWT,$Current_User_id)
 { 
 try {
 $decoded = JWT::decode($JWT,$this->Secret_Key, array('HS256'));
 $payload = json_decode(json_encode($decoded),true);
 
 if($payload['uId'] == $Current_User_id) {
 $res=array("status"=>true);
 }else{
 $res=array("status"=>false,"Error"=>"Invalid Token or Token Exipred, So Please login Again!");
 }
 }catch (UnexpectedValueException $e) {
 $res=array("status"=>false,"Error"=>$e->getMessage());
 } 
 return $res;
 
 }
}

$return=array();
$obj = new DBClass();
if(isset($_GET['action']) && $_GET['action']!='')
{
if($_GET['action']=="login")
{
 if(isset($_POST['email']) && isset($_POST['password']))
 {
 $UserData=$obj->login($_POST['email'],$_POST['password']);
 if(count($UserData)>0)
 {
 $return['status']=1;
 $return['_data_']=$UserData[0];
 $return['message']='User Logged in Successfully.';

 $jwt=$obj->generateToken($UserData[0]['id']);
 if($jwt['status']==true)
 {
 $return['JWT']=$jwt['Token'];
 }
 else{
 unset($return['_data_']);
 $return['status']=0;
 $return['message']='Error:'.$jwt['Error'];
 }
 
 }
 else
 {
	$return['status']=0;
	$return['message']='Error:Invalid Email or Password!';
 }
 }
 else
 {
 $return['status']=0;
 $return['message']='Error:Email or Password not provided!';
 }
}
elseif($_GET['action']=="UserBlogs")
{
 if(isset($_POST['Uid']))
 {

 $resp=$obj->Authenticate($_POST['JWT'],$_POST['Uid']);
 if($resp['status']==false)
 {
 $return['status']=0;
 $return['message']='Error:'.$resp['Error'];
 }
 else{
 $blogs=$obj->get_all_blogs($_POST['Uid']);
 if(count($blogs)>0)
 {
 $return['status']=1;
 $return['_data_']=$blogs;
 $return['message']='Success.';
 }
 else
 {
 $return['status']=0;
 $return['message']='Error:Invalid UserId!';
 }
 } 
 }
 else
 {
 $return['status']=0;
 $return['message']='Error:User Id not provided!';
 }
}
}
else
{
$return['status']=0;
$return['message']='Error:Action not provided!';
}
$obj->response($return);
$obj->connection=null;
?>

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.

It took me quite some time to settle on my first blog post in this series and I found myself thinking about the most requested functionality in my career – The good ‘ol Custom CMS – typically geared towards clients that want a straight forward, secure solution that can be expanded upon in a modular format and that’s their IP.

This will be our starting point. A blank slate to build something epic with clean code and even cleaner design. And in the spirit of building from scratch, I will refrain from using classes or a framework. The main reasoning behind this is to truly get everyone acquainted with and excited about PHP development.

Join me as I transform rudimentary code into something extraordinary that can be morphed into just about any Content, PHP, and MySQL driven project. So without further ado, let’s jump into it!

The bare necessities

If you’re just getting started with development, there’s a nifty bite sized server called UniformServer that will be your best friend throughout your coding career. PHPMyAdmin (an awesome visual db management tool) comes built in so if you’re looking for a work right out of the box solution, this is it.

Alternatively, you can opt for XAMPP or use an alternative server of your choice.

Now here’s where the exciting stuff begins, mapping things out.

I don’t see this done/encouraged often enough. Feel free to grab a piece of paper to logically map out your steps or produce a rough draft of where you’d like this project to go.

In this tutorial, I would like to achieve the following:

DB, DB, Set up your DB.

This requires a bit of planning but let’s start of with the basic structure we need to see this through.

We are going to need a user table and a content table and are a few ways to tackle this.

If you’re using the PHPMyAdmin tool you can create your database, add user permissions (Click on Permissions after creating your database), and create a table with ease.



If you’re like me and prefer to look at good ‘ol SQL then writing an SQL statement is the preferred approach.

CREATE TABLE <code>mydbname</code>.<code>content</code> ( <code>ID</code> INT(11) NOT NULL AUTO_INCREMENT , <code>title</code> VARCHAR(100) NOT NULL , <code>content</code> LONGTEXT NOT NULL , <code>author</code> VARCHAR(50) NOT NULL , PRIMARY KEY (<code>ID</code>)) ENGINE = MyISAM COMMENT = 'content table';

Understanding the SQL statement

In a nutshell we are creating a table with important fields. Namely:

####

ID | Title | Content | Author

#######

The ID field is our unique identifier.Now we can move on to the file structure.

Everything has a place in the file structure game

You can use a structure that speaks to your coding style / memory.

I tend to use the following:



Choose a name for your CMS, which should be placed at the webroot of your localhost/server.

Replicate the folder structure as per the above example.

Next, we’re going to create a basic connection file.

You can create a conn.php file in your root/includes folder.

The connection file will provide crucial information to connect to the database.

Type the following into your conn.php file, remember to include your own database credentials.

<?php

$letsconnect = new mysqli("localhost","dbuser","dbpass","dbname");

?>

Let’s go to the homepage (index.php)

Create a file called index.php at the root of your CMS folder.

I will be adding comments in my code to help you understand what each line does.

Comments are a useful tool for developers to add important notes private to their code.

We need to pull information from the database so it’s imperative that we include our connection file.

<?php

include('includes/conn.php');

if ($letsconnect -> connect_errno) { echo "Error " . $letsconnect -> connect_error;

}else{

$getmydata=$letsconnect -> query("SELECT * FROM content");

foreach($getmydata as $mydata){	echo "Title: ";	echo $mydata['title'];	echo "<br/>";	echo "Content: ";	echo $mydata['content'];	echo "<br/>";	echo "Author: ";	echo $mydata['author'];	echo "<br/>";	echo "<br/>";

}

}

$letsconnect -> close();

?>

Let’s get a (very) basic backend up and running

Create a file called index.php in your backend folder.

We need to create a basic form to capture our data.

Let’s code some HTML!

<html>

<head><title>Backend - Capture Content</title></head>

<body>

<form action="<?php $_SERVER[‘PHP_SELF’];?>" method="post">

<input type="text" name="title" placeholder="Content Title here" required/>

<textarea name="content">Content Here</textarea>

<input type="text" name="author" placeholder="Author" required/>

<input type="submit" value="Save My Data" name="savedata"/>

</form>

</body>

</html>

Next, we need to process the form data.

Type the following just above the

<form> 

tag.

<?php

if(isset($_POST['savedata'])){

include('../includes/conn.php');

if ($letsconnect->connect_error) {

die("Your Connection failed: " . $letsconnect->connect_error);

}else{

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

if (mysqli_query($letsconnect, $sql)) {

echo "Your data was saved successfully!";

} else { echo "Error: " . $sql . "" . mysqli_error($letsconnect);

} $letsconnect->close();

}

}

?>

Note, this is a basic MySQL query to insert data. However, before using this in production it's important to add proper escaping and security to prevent SQL injections. This will be covered in the next article.

Congrats you made it to the end of tutorial 1!

Test out your creation, modify your content, and play around.

Go to your sitename/index.php to see your frontend after capturing data via sitename/backend/index.php

Next Up:

codewithme Now With Security, Functionality, and Aesthetics in mind.

Conclusion

Coding doesn’t have to be daunting and it’s my aim to divide a complex system into bitesized tutorials so you can truly use the knowledge you’ve acquired in your own projects.

Halloween is filled with ghouls, ghosts, zombies and lots of other spookiness, but the scariest thing ever is FOMO. It’s conference season and several have their call for papers out (including us at Nomad PHP :D). This is the perfect time for you to share your knowledge with the community. Whether it’s your first time or 100th time - it can be scary to put yourself out there and do a talk, but worse than that is not taking the chance and submitting your talk and doing the presentation. Plus, many of these events host lightning talks (short 5-15 minute talks) - meaning you can test out your talk risk free ;)

So here is your chance - submit for one or submit for all of them. May the odds be ever in your favor!

Fosdem 2019

First we have Fosdem 2019 which will take place on February 2 & 3 in Brussels,Belgium. Some facts about this call for papers:
*Deadline: November 3, 2018
* Presentations are expected to be 50 minutes long (including audience questions) and should cater to a varied technical audience. For examples check out youtube.
*Submit your proposals via Pentabarf: https://fosdem.org/submit.
* The conference covers reasonable travel expenses agreed upon in advance as well as arranges accommodations

Midwest PHP 2019

Next up we have Midwest PHP which will take place on March 8 & 9 in Bloomington, Minnesota.
*Deadline: November 15, 2018
* There is a speaker package included (conference pass, 2 hotel nights, airfare/travel - $500 max, lunch, etc.)
* Make sure the talk title and abstract define the exact topic and what you hope people will learn from it.
* Recommended to submit more than one talk because it can increase your chances of one of them being picked.
*Submit your talk here: [https://cfp.midwestphp.org/] (https://cfp.midwestphp.org/)

Longhorn PHP

Next we have Longhorn PHP which will take place on May 2 (tutorial day) then MAy 3 &4 (conference) in Austin, Texas.
*Deadline: December 15, 2018
* For all speakers, you'll get a full conference pass (tutorial day and main conference days), including access to lunch, after-parties, and any other activities included in the conference.
* For speakers remote to the Austin area, we'll provide 3 nights at the speaker hotel (4 nights if presenting a talk and a tutorial) near the conference venue.
* For speakers outside Texas, we'll book you an Economy or equivalent round-trip airfare on a flight into Austin we'd be comfortable taking ourselves (we're conference speakers too!). Plus, we'll arrange transportation between the Austin airport and the speaker hotel.
* Three different session lengths: 3 hour tutorials, 60 minute talks, and 30 minute talks.
* It doesn't have to just be a PHP related talk. For more information on talks click here.
*Submit your talk here: https://cfp.longhornphp.com/.

Laravel Live India 2019

Then we have LaravelLive India 2019 in Mumbai, India.
*Deadline: December 31, 2018
* Talk length is 30 minutes - Q&A up to the presenters discretion but would be included in the 30 minute time limit.
* Talks will be recorded and distributed for free as well as the presentation slides.
* Looking for a range of talks from PHP (security, testing and frameworks), web development, HTML5, JavaScript, mobile development, emerging technologies and non-technical proposals that will appeal to developers.
*Talk guidelines: Objective with clear expectation for audience, short and to the point description, mention of employer is only allowed at the beginning of the content and background image/wallpaper shouldn’t include company name/logos.
*Submit your talk here: [https://www.papercall.io/laravellive-india] (https://www.papercall.io/laravellive-india)

Nomad PHP

(you know you want to)

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.
*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.
*Submit here: [https://www.papercall.io/nomadphp] (https://www.papercall.io/nomadphp)
Now that you have some information - it’s the perfect time to take it all in and get started on your talk proposals :)! Looking forward to seeing all the amazing talks that will be coming out!!!

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.