simple-php-router/src/Pecee/CsrfToken.php

<?php
namespace Pecee;

class CsrfToken
{
	const CSRF_KEY = 'XSRF-TOKEN';

	protected $token;

	/**
	 * Generate random identifier for CSRF token
	 *
	 * @return string
	 */
	public static function generateToken()
	{
		if (function_exists('mcrypt_create_iv')) {
			return bin2hex(mcrypt_create_iv(32, MCRYPT_DEV_URANDOM));
		}
		return bin2hex(openssl_random_pseudo_bytes(32));
	}

	/**
	 * Validate valid CSRF token
	 *
	 * @param string $token
	 * @return bool
	 */
	public function validate($token)
	{
		if ($token !== null && $this->getToken() !== null) {
			return hash_equals($token, $this->getToken());
		}
		return false;
	}

	/**
	 * Set csrf token cookie
	 *
	 * @param $token
	 */
	public function setToken($token)
	{
		setcookie(static::CSRF_KEY, $token, time() + 60 * 120, '/');
	}

	/**
	 * Get csrf token
	 * @return string|null
	 */
	public function getToken()
	{
		if ($this->hasToken()) {
			return $_COOKIE[static::CSRF_KEY];
		}
		return null;
	}

	/**
	 * Returns whether the csrf token has been defined
	 * @return bool
	 */
	public function hasToken()
	{
		return isset($_COOKIE[static::CSRF_KEY]);
	}

}