Ipv6::check_ipv6( string $ip )

Checks an IPv6 address


Description

Checks if the given IP is a valid IPv6 address


Parameters

$ip

(Required) An IPv6 address


Return

(bool) true if $ip is a valid IPv6 address


Source

File: wp-includes/Requests/src/Ipv6.php

	public static function check_ipv6($ip) {
		// Note: Input validation is handled in the `uncompress()` method, which is the first call made in this method.
		$ip                = self::uncompress($ip);
		list($ipv6, $ipv4) = self::split_v6_v4($ip);
		$ipv6              = explode(':', $ipv6);
		$ipv4              = explode('.', $ipv4);
		if (count($ipv6) === 8 && count($ipv4) === 1 || count($ipv6) === 6 && count($ipv4) === 4) {
			foreach ($ipv6 as $ipv6_part) {
				// The section can't be empty
				if ($ipv6_part === '') {
					return false;
				}

				// Nor can it be over four characters
				if (strlen($ipv6_part) > 4) {
					return false;
				}

				// Remove leading zeros (this is safe because of the above)
				$ipv6_part = ltrim($ipv6_part, '0');
				if ($ipv6_part === '') {
					$ipv6_part = '0';
				}

				// Check the value is valid
				$value = hexdec($ipv6_part);
				if (dechex($value) !== strtolower($ipv6_part) || $value < 0 || $value > 0xFFFF) {
					return false;
				}
			}

			if (count($ipv4) === 4) {
				foreach ($ipv4 as $ipv4_part) {
					$value = (int) $ipv4_part;
					if ((string) $value !== $ipv4_part || $value < 0 || $value > 0xFF) {
						return false;
					}
				}
			}

			return true;
		} else {
			return false;
		}
	}