diff options
Diffstat (limited to 'includes/IP.php')
| -rw-r--r-- | includes/IP.php | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/includes/IP.php b/includes/IP.php new file mode 100644 index 00000000..f3ff3427 --- /dev/null +++ b/includes/IP.php @@ -0,0 +1,211 @@ +<?php +/* + * Collection of public static functions to play with IP address + * and IP blocks. + * + * @Author "Ashar Voultoiz" <hashar@altern.org> + * @License GPL v2 or later + */ + +// Some regex definition to "play" with IP address and IP address blocks + +// An IP is made of 4 bytes from x00 to xFF which is d0 to d255 +define( 'RE_IP_BYTE', '(25[0-5]|2[0-4]\d|1?\d{1,2})'); +define( 'RE_IP_ADD' , RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE ); +// An IP block is an IP address and a prefix (d1 to d32) +define( 'RE_IP_PREFIX' , '(3[0-2]|[12]?\d)'); +define( 'RE_IP_BLOCK', RE_IP_ADD . '\/' . RE_IP_PREFIX); + +class IP { + + /** + * Validate an IP address. + * @return boolean True if it is valid. + */ + public static function isValid( $ip ) { + return preg_match( '/^' . RE_IP_ADD . '$/', $ip, $matches) ; + } + + /** + * Validate an IP Block. + * @return boolean True if it is valid. + */ + public static function isValidBlock( $ipblock ) { + return ( count(self::toArray($ipblock)) == 1 + 5 ); + } + + /** + * Determine if an IP address really is an IP address, and if it is public, + * i.e. not RFC 1918 or similar + * Comes from ProxyTools.php + */ + public static function isPublic( $ip ) { + $n = IP::toUnsigned( $ip ); + if ( !$n ) { + return false; + } + + // ip2long accepts incomplete addresses, as well as some addresses + // followed by garbage characters. Check that it's really valid. + if( $ip != long2ip( $n ) ) { + return false; + } + + static $privateRanges = false; + if ( !$privateRanges ) { + $privateRanges = array( + array( '10.0.0.0', '10.255.255.255' ), # RFC 1918 (private) + array( '172.16.0.0', '172.31.255.255' ), # " + array( '192.168.0.0', '192.168.255.255' ), # " + array( '0.0.0.0', '0.255.255.255' ), # this network + array( '127.0.0.0', '127.255.255.255' ), # loopback + ); + } + + foreach ( $privateRanges as $r ) { + $start = IP::toUnsigned( $r[0] ); + $end = IP::toUnsigned( $r[1] ); + if ( $n >= $start && $n <= $end ) { + return false; + } + } + return true; + } + + /** + * Split out an IP block as an array of 4 bytes and a mask, + * return false if it cant be determined + * + * @parameter $ip string A quad dotted IP address + * @return array + */ + public static function toArray( $ipblock ) { + if(! preg_match( '/^' . RE_IP_ADD . '(?:\/(?:'.RE_IP_PREFIX.'))?' . '$/', $ipblock, $matches ) ) { + return false; + } else { + return $matches; + } + } + + /** + * Return a zero-padded hexadecimal representation of an IP address. + * + * Hexadecimal addresses are used because they can easily be extended to + * IPv6 support. To separate the ranges, the return value from this + * function for an IPv6 address will be prefixed with "v6-", a non- + * hexadecimal string which sorts after the IPv4 addresses. + * + * @param $ip Quad dotted IP address. + */ + public static function toHex( $ip ) { + $n = self::toUnsigned( $ip ); + if ( $n !== false ) { + $n = sprintf( '%08X', $n ); + } + return $n; + } + + /** + * Given an IP address in dotted-quad notation, returns an unsigned integer. + * Like ip2long() except that it actually works and has a consistent error return value. + * Comes from ProxyTools.php + * @param $ip Quad dotted IP address. + */ + public static function toUnsigned( $ip ) { + if ( $ip == '255.255.255.255' ) { + $n = -1; + } else { + $n = ip2long( $ip ); + if ( $n == -1 || $n === false ) { # Return value on error depends on PHP version + $n = false; + } + } + if ( $n < 0 ) { + $n += pow( 2, 32 ); + } + return $n; + } + + /** + * Convert a dotted-quad IP to a signed integer + * Returns false on failure + */ + public static function toSigned( $ip ) { + if ( $ip == '255.255.255.255' ) { + $n = -1; + } else { + $n = ip2long( $ip ); + if ( $n == -1 ) { + $n = false; + } + } + return $n; + } + + /** + * Convert a network specification in CIDR notation to an integer network and a number of bits + */ + public static function parseCIDR( $range ) { + $parts = explode( '/', $range, 2 ); + if ( count( $parts ) != 2 ) { + return array( false, false ); + } + $network = IP::toSigned( $parts[0] ); + if ( $network !== false && is_numeric( $parts[1] ) && $parts[1] >= 0 && $parts[1] <= 32 ) { + $bits = $parts[1]; + if ( $bits == 0 ) { + $network = 0; + } else { + $network &= ~((1 << (32 - $bits)) - 1); + } + # Convert to unsigned + if ( $network < 0 ) { + $network += pow( 2, 32 ); + } + } else { + $network = false; + $bits = false; + } + return array( $network, $bits ); + } + + /** + * Given a string range in a number of formats, return the start and end of + * the range in hexadecimal. + * + * Formats are: + * 1.2.3.4/24 CIDR + * 1.2.3.4 - 1.2.3.5 Explicit range + * 1.2.3.4 Single IP + */ + public static function parseRange( $range ) { + if ( strpos( $range, '/' ) !== false ) { + # CIDR + list( $network, $bits ) = IP::parseCIDR( $range ); + if ( $network === false ) { + $start = $end = false; + } else { + $start = sprintf( '%08X', $network ); + $end = sprintf( '%08X', $network + pow( 2, (32 - $bits) ) - 1 ); + } + } elseif ( strpos( $range, '-' ) !== false ) { + # Explicit range + list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) ); + if ( $start > $end ) { + $start = $end = false; + } else { + $start = IP::toHex( $start ); + $end = IP::toHex( $end ); + } + } else { + # Single IP + $start = $end = IP::toHex( $range ); + } + if ( $start === false || $end === false ) { + return array( false, false ); + } else { + return array( $start, $end ); + } + } +} +?> |