for::getHtmlToSpreadCookiesOverSites

protected function getHtmlToSpreadCookiesOverSites()
{
	static $firstExecution = true;

	if (!$firstExecution)
		throw new NotSupportedException("getHtmlToSpreadCookiesOverSites() must be called only once");

	if (ConfigOption::get("main", "ALLOW_SPREAD_COOKIE", "Y") !== "Y")
		return "";

	$result = "";

	$context = $this->getContext();
	/** @var $response HttpResponse */
	$response = $context->getResponse();

	$params = "";
	foreach ($response->getCookies() as $cookie)
	{
		/** @var $cookie BitrixMainWebCookie */
		if ($cookie->getSpread() & WebCookie::SPREAD_SITES)
			$params .= $cookie->getName().chr(1).$cookie->getValue().chr(1).$cookie->getExpires().chr(1).$cookie->getPath().chr(1).''.chr(1).$cookie->getSecure().chr(2);
	}

	if (isset($_SESSION['SPREAD_COOKIE']) && is_array($_SESSION['SPREAD_COOKIE']) && !empty($_SESSION['SPREAD_COOKIE']))
	{
		reset($_SESSION['SPREAD_COOKIE']);
		while (list($cookieName, $cookieData) = each($_SESSION['SPREAD_COOKIE']))
		{
			$cookieData["D"] = ""; // domain must be empty
			$params .= $cookieName.chr(1).$cookieData["V"].chr(1).$cookieData["T"].chr(1).$cookieData["F"].chr(1).$cookieData["D"].chr(1).$cookieData["S"].chr(2);
		}
		unset($_SESSION['SPREAD_COOKIE']);
	}

	if (!empty($params))
	{
		$server = $context->getServer();

		/** @var $request HttpRequest */
		$request = $context->getRequest();
		$versionFile = new IOFile(IOPath::convertRelativeToAbsolute("/bitrix/modules/main/classes/general/version.php"));
		$salt = $request->getRemoteAddress()."|".$versionFile->getModificationTime()."|".LICENSE_KEY;
		$params = "s=".urlencode(base64_encode($params))."&k=".urlencode(md5($params.$salt));

		$domainList = array();
		$domainList[] = $server->getHttpHost();
		$recordset = SiteTable::getList(
			array(
				'filter' => array('ACTIVE' => 'Y'),
			)
		);
		while ($record = $recordset->Fetch())
		{
			$siteDomainsList = explode("n", str_replace("r", "n", $record["DOMAINS"]));
			if (is_array($siteDomainsList) && count($siteDomainsList) > 0)
			{
				foreach ($siteDomainsList as $d)
				{
					$d = trim($d);
					if (!empty($d))
						$domainList[] = $d;
				}
			}
		}

		if (count($domainList) > 0)
		{
			$uniqueDomainList = array();
			$domainList = array_unique($domainList);
			$domainList2 = array_unique($domainList);
			foreach ($domainList as $domain1)
			{
				$goodDomain = true;
				foreach ($domainList2 as $domain2)
				{
					if (strlen($domain1) > strlen($domain2) && substr($domain1, -(strlen($domain2) + 1)) == ".".$domain2)
					{
						$goodDomain = false;
						break;
					}
				}
				if ($goodDomain)
					$uniqueDomainList[] = $domain1;
			}

			$protocol = ($request->isHttps()) ? "https://" : "http://";
			$host = $server->getHttpHost();
			$requestUri = $request->getRequestUri();

			$currentUri = new WebUri($protocol.$host."/".$requestUri, WebUriType::ABSOLUTE);
			$currentUriParts = $currentUri->parse();

			foreach ($uniqueDomainList as $domain)
			{
				$uriString = $protocol.$domain."/bitrix/spread.php?".$params;
				$domainUri = new WebUri($uriString, WebUriType::ABSOLUTE);
				$domainUriParts = $domainUri->parse();

				if ($currentUriParts["host"] != $domainUriParts["host"])
					$result .= ''."n";
			}
		}
	}

	$firstExecution = false;

	return $result;
}