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@CMCDragonkai
Created January 6, 2014 07:07
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PHP: Codeigniter CSRF functionality does not support putting the CSRF token in the HTTP headers for the purposes of the double submit cookie method. It also only runs the CSRF check on POST and not on PUT or DELETE. This drop in MY_Security.php makes sure CSRF runs on POST, PUT or DELETE and checks the HTTP headers for X-XSRF-TOKEN recommended b…
<?php
class MY_Security extends CI_Security{
//overriding the normal csrf_verify, this gets automatically called in the Input library's constructor
//verifying on POST and PUT and DELETE
public function csrf_verify(){
$request_method = strtoupper($_SERVER['REQUEST_METHOD']);
//If it is GET, ignore the rest
if($request_method == 'GET' OR $request_method == 'HEAD' OR $request_method == 'OPTIONS'){
return $this->csrf_set_cookie();
}
// Check if URI has been whitelisted from CSRF checks
if($exclude_uris = config_item('csrf_exclude_uris')){
$uri = load_class('URI', 'core');
if(in_array($uri->uri_string(), $exclude_uris)){
return $this;
}
}
//Double submit cookie method: COOKIE needs to exist and at least either POST or SERVER needs to exist and at least one of the POST or SERVER must match the COOKIE
if(
!isset($_COOKIE[$this->_csrf_cookie_name])
OR
(
!isset($_POST[$this->_csrf_cookie_name])
AND
!isset($_SERVER['HTTP_X_XSRF_TOKEN'])
)
){
$this->csrf_show_error();
}
//if CSRF token was in the POST, then it needs to match the cookie
if(isset($_POST[$this->_csrf_token_name])){
if($_POST[$this->_csrf_token_name] !== $_COOKIE[$this->_csrf_cookie_name]){
$this->csrf_show_error();
}
}
//if CSRF token was in the SERVER (headers), then it needs to match the cookie
if(isset($_SERVER['HTTP_X_XSRF_TOKEN'])){
if($_SERVER['HTTP_X_XSRF_TOKEN'] !== $_COOKIE[$this->_csrf_cookie_name]){
$this->csrf_show_error();
}
}
// We kill this since we're done and we don't want to polute the _POST array
unset($_POST[$this->_csrf_token_name]);
if(config_item('csrf_regenerate')){
unset($_COOKIE[$this->_csrf_cookie_name]);
$this->_csrf_hash = '';
}
$this->_csrf_set_hash();
$this->csrf_set_cookie();
log_message('debug', 'CSRF token verified');
return $this;
}
}
@CMCDragonkai
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I'm not working in codeigniter anymore, so if anyone has updates to it, feel free to post it and I'll update the gist.

@rkorebrits
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rkorebrits commented Dec 20, 2017

Edit: This is because Nginx apparently doesn't support this function. See the comments on http://php.net/manual/en/function.getallheaders.php for a solution.

@MohannadNaj
I get this error when I implement your code:

 
  Fatal error: Uncaught Error: Class 'CI_Controller' not found in /projects/ditto/www/system/core/CodeIgniter.php:366
  Stack trace:
  #0 /projects/ditto/www/system/core/Common.php(462): get_instance()
  #1 /projects/ditto/www/system/core/Exceptions.php(105): log_message('error', 'Severity: error...')
  #2 /projects/ditto/www/system/core/Common.php(727): CI_Exceptions->log_exception('error', 'Exception: Call...', '/projects/ditto...', 6)
  #3 [internal function]: _exception_handler(Object(Error))
  #4 {main}
  thrown in /projects/ditto/www/system/core/CodeIgniter.php on line 366
 
  Fatal error: Uncaught Error: Class 'CI_Controller' not found in /projects/ditto/www/system/core/CodeIgniter.php:366
  Stack trace:
  #0 /projects/ditto/www/system/core/Common.php(462): get_instance()
  #1 /projects/ditto/www/system/core/Exceptions.php(105): log_message('error', 'Severity: Error...')
  #2 /projects/ditto/www/system/core/Common.php(690): CI_Exceptions->log_exception('Error', 'Uncaught Error:...', '/projects/ditto...', 366)
  #3 /projects/ditto/www/system/core/Common.php(766): _error_handler(1, 'Uncaught Error:...', '/projects/ditto...', 366)
  #4 [internal function]: _shutdown_handler()
  #5 {main}
  thrown in /projects/ditto/www/system/core/CodeIgniter.php on line 366
   

Any idea what it could be?

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