protected function runHostnameSafeguards($hostDetails, $hostname)
{
// special case - hostname is already set in hostDetails
//
// we assume that it was set in the test environment config file
// by someone who knows what they are doing
if (isset($hostDetails->hostname)) {
return $hostDetails->hostname;
}
// special case - no IP address for the host
//
// we need the host's IP address to perform our checks
if (!isset($hostDetails->ipAddress)) {
return $hostname;
}
// check for machines calling themselves 'localhost' in some form
// or another
//
// this can happen when there is no working dynamic DNS
$parts = explode(".", $hostname);
if ($parts[0] == 'localhost') {
// this is only valid *if* the host's IP address is recognised
// as a valid loopback address
//
// most of the world uses 127.0.0.1
// ubuntu uses 127.0.1.1 (no idea why)
$validIps = ['127.0.0.1', '127.0.1.1'];
if (!in_array($hostDetails->ipAddress, $validIps)) {
// this hostname is *not* safe
//
// the best we can do is return the host's IP address
return $hostDetails->ipAddress;
}
}
// check if the machine's hostname resolves to the detected IP
// address or not
$resolvedIp = gethostbyname($hostname);
if ($resolvedIp != $hostDetails->ipAddress) {
// no good
//
// possibilities include:
//
// * no DNS entry for $hostname
// * no /etc/hosts entry for $hostname
//
// the best we can do is return the host's IP address
return $hostDetails->ipAddress;
}
// *if* we get here, then we believe that $hostname is safe to
// use in your stories
return $hostname;
}
