rue;
}
}
}
}
return false;
}
/**
* Works around the REMOTE_ADDR not containing the user's IP
*/
public static function workaroundIPIssues(): void
{
$ip = self::getIp();
if (array_key_exists('REMOTE_ADDR', $_SERVER) && ($_SERVER['REMOTE_ADDR'] == $ip))
{
return;
}
if (array_key_exists('REMOTE_ADDR', $_SERVER))
{
$_SERVER['FOF_REMOTE_ADDR'] = $_SERVER['REMOTE_ADDR'];
}
elseif (function_exists('getenv'))
{
if (getenv('REMOTE_ADDR'))
{
$_SERVER['FOF_REMOTE_ADDR'] = getenv('REMOTE_ADDR');
}
}
$_SERVER['REMOTE_ADDR'] = $ip;
}
/**
* Should I allow the remote client's IP to be overridden by an X-Forwarded-For or Client-Ip HTTP header?
*
* @param bool $newState True to allow the override
*
* @return void
*/
public static function setAllowIpOverrides(bool $newState): void
{
self::$allowIpOverrides = $newState;
}
/**
* Is it an IPv6 IP address?
*
* @param string $ip An IPv4 or IPv6 address
*
* @return boolean True if it's IPv6
*/
protected static function isIPv6(string $ip): bool
{
return strstr($ip, ':') !== false;
}
/**
* Gets the visitor's IP address. Automatically handles reverse proxies
* reporting the IPs of intermediate devices, like load balancers. Examples:
* https://www.akeeba.com/support/admin-tools/13743-double-ip-adresses-in-security-exception-log-warnings.html
* http://stackoverflow.com/questions/2422395/why-is-request-envremote-addr-returning-two-ips
* The solution used is assuming that the first IP address is the external one (unless $useFirstIpInChain is set to
* false)
*
* @return string
*/
protected static function detectAndCleanIP(): string
{
$ip = static::detectIP();
if ((strstr($ip, ',') !== false) || (strstr($ip, ' ') !== false))
{
$ip = str_replace(' ', ',', $ip);
$ip = str_replace(',,', ',', $ip);
$ips = explode(',', $ip);
$ip = '';
// Loop until we're running out of parts or we have a hit
while ($ips)
{
$ip = array_shift($ips);
$ip = trim($ip);
if (self::$useFirstIpInChain)
{
return self::cleanIP($ip);
}
}
}
return self::cleanIP($ip);
}
protected static function cleanIP(string $ip): string
{
$ip = trim($ip);
$ip = strtoupper($ip);
/**
* Work around IPv4-mapped addresses.
*
* IPv4 addresses may be embedded in an IPv6 address. This is always 80 zeroes, 16 ones and the IPv4 address.
* In all possible IPv6 notations this is:
* 0:0:0:0:0:FFFF:192.168.1.1
* ::FFFF:192.168.1.1
* ::FFFF:C0A8:0101
*
* @see http://www.tcpipguide.com/free/t_IPv6IPv4AddressEmbedding-2.htm
*/
if ((strpos($ip, '::FFFF:') === 0) || (strpos($ip, '0:0:0:0:0:FFFF:') === 0))
{
// Fast path: the embedded IPv4 is in decimal notation.
if (strstr($ip, '.') !== false)
{
return substr($ip, strrpos($ip, ':') + 1);
}
// Get the embedded IPv4 (in hex notation)
$ip = substr($ip, strpos($ip, ':FFFF:') + 6);
// Convert each 16-bit WORD to decimal
[$word1, $word2] = explode(':', $ip);
$word1 = hexdec($word1);
$word2 = hexdec($word2);
$longIp = $word1 * 65536 + $word2;
return long2ip($longIp);
}
return $ip;
}
/**
* Gets the visitor's IP address
*
* @return string
*/
protected static function detectIP(): string
{
// Normally the $_SERVER superglobal is set
if (isset($_SERVER))
{
// Do we have IP overrides enabled?
if (static::$allowIpOverrides)
{
// If so, check for every proxy header
foreach (static::$proxyHeaders as $header)
{
if (array_key_exists($header, $_SERVER))
{
return $_SERVER[$header];
}
}
}
// CLI applications
if (!array_key_exists('REMOTE_ADDR', $_SERVER))
{
return '';
}
// Normal, non-proxied server or server behind a transparent proxy
return $_SERVER['REMOTE_ADDR'];
}
// This part is executed on PHP running as CGI, or on SAPIs which do
// not set the $_SERVER superglobal
// If getenv() is disabled, you're screwed
if (!function_exists('getenv'))
{
return '';
}
// Do we have IP overrides enabled?
if (static::$allowIpOverrides)
{
// If so, check for every proxy header
foreach (static::$proxyHeaders as $header)
{
if (getenv($header))
{
return getenv($header);
}
}
}
// Normal, non-proxied server or server behind a transparent proxy
if (getenv('REMOTE_ADDR'))
{
return getenv('REMOTE_ADDR');
}
// Catch-all case for broken servers and CLI applications
return '';
}
/**
* Converts inet_pton output to bits string
*
* @param string $inet The in_addr representation of an IPv4 or IPv6 address
*
* @return string
*/
protected static function inet_to_bits(string $inet): string
{
$unpacked = strlen($inet) == 4 ? unpack('C4', $inet) : unpack('C16', $inet);
$binaryip = '';
foreach ($unpacked as $byte)
{
$binaryip .= str_pad(decbin($byte), 8, '0', STR_PAD_LEFT);
}
return $binaryip;
}
/**
* Checks if an IPv6 address $ip is part of the IPv6 CIDR block $cidrnet
*
* @param string $ip The IPv6 address to check, e.g. 21DA:00D3:0000:2F3B:02AC:00FF:FE28:9C5A
* @param string $cidrnet The IPv6 CIDR block, e.g. 21DA:00D3:0000:2F3B::/64
*
* @return bool
*/
protected static function checkIPv6CIDR(string $ip, string $cidrnet): bool
{
$ip = inet_pton($ip);
$binaryip = self::inet_to_bits($ip);
[$net, $maskbits] = explode('/', $cidrnet);
$net = inet_pton($net);
$binarynet = self::inet_to_bits($net);
$ip_net_bits = substr($binaryip, 0, $maskbits);
$net_bits = substr($binarynet, 0, $maskbits);
return $ip_net_bits === $net_bits;
}
}
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