Laravel | CSRF Protection

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Cross-Site Request Forgery (CSRF) is a type of attack that performed by the attacker to send requests to a system with the help of an authorized user who is trusted by the system.

Laravel provides protection with the CSRF attacks by generating a CSRF token. This CSRF token is generated automatically for each user. This token is nothing but a random string that is managed by the Laravel application to verify the user requests.

How to Use: This CSRF token protection can be applied to any HTML form in Laravel application by specifying a hidden form field of CSRF token. The requests are validated automatically by the CSRF VerifyCsrfToken middleware.

There are three different ways in which you can do this.

@csrf
csrf_field()
csrf_token()

@csrf: This is a blade template directive for generating the hidden input field in the HTML form.

Syntax:

<form method="POST">
  @csrf  // Generate hidden input field
  .....
  .....
</form>

Example:

<!DOCTYPE html> 
<html> 
    <head> 
        <title>Laravel | CSRF Protection</title> 
    </head> 
    <body> 
        <section> 
            <h1>CSRF Protected HTML Form</h1> 
            <form method="POST"> 
                @csrf 
                  
                <input type="text" name="username" 
                                            placeholder="Username"> 
                <input type="password" name="password" 
                                            placeholder="Password"> 
                <input type="submit" name="submit" value="Submit"> 
            </form> 
        </section> 
    </body> 
</html> 

csrf_field(): This function can be used to generate the hidden input field in the HTML form.

Note: This function should be written inside double curly braces.

Syntax:

<form method="POST"<

  // Generate hidden input field
  {{ csrf_field() }}  
  .....
  .....
</form>

Example:

<!DOCTYPE html> 
<html> 
    <head> 
        <title>Laravel | CSRF Protection</title> 
    </head> 
    <body> 
        <section> 
            <h1>CSRF Protected HTML Form</h1> 
            <form method="POST"> 
                {{ csrf_field() }} 
                  
                <input type="text" name="username" 
                                       placeholder="Username"> 
                <input type="password" name="password"
                                       placeholder="Password"> 
                <input type="submit" name="submit" 
                                               value="Submit"> 
            </form> 
        </section> 
    </body> 
</html> 

csrf_token(): This function just gives a random string. This function does not generate the hidden input field.

Note: HTML input field should be written explicitly. This function should be written inside double curly braces.

Syntax:

<form method="POST">
  <input type="hidden" name="_token" value="{{ csrf_token() }}">
  .....
  .....
</form>

Example:

<!DOCTYPE html> 
<html> 
    <head> 
        <title>Laravel | CSRF Protection</title> 
    </head> 
    <body> 
        <section> 
            <h1>CSRF Protected HTML Form</h1> 
            <form method="POST"> 
                <input type="hidden" name="_token" value="{{ csrf_token() }}"> 
                  
                <input type="text" name="username" 
                                 placeholder="Username"> 
                <input type="password" name="password"
                                 placeholder="Password"> 
                <input type="submit" name="submit" 
                                         value="Submit"> 
            </form> 
        </section> 
    </body> 
</html> 

Output: The output is going to be the same for any of the above three ways to generate a CSRF token. The CSRF token field should be written/generated at the start of every HTML form, using any of the three ways, in a Laravel application.