JEMBOT MAWOT Bypass Shell

<?php

namespace DoctrineExtensions\Query\Mysql;

use Doctrine\ORM\Query\AST\Functions\FunctionNode;
use Doctrine\ORM\Query\Lexer;

class Ascii extends FunctionNode
{
    private $string;

    public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
    {
        return 'ASCII('.$sqlWalker->walkArithmeticPrimary($this->string).')';
    }

    public function parse(\Doctrine\ORM\Query\Parser $parser)
    {
        $parser->match(Lexer::T_IDENTIFIER);
        $parser->match(Lexer::T_OPEN_PARENTHESIS);

        $this->string = $parser->ArithmeticExpression();

        $parser->match(Lexer::T_CLOSE_PARENTHESIS);
    }
}