includes/IP.php

   1 <?php
   2 /*
   3  * Collection of public static functions to play with IP address
   4  * and IP blocks.
   5  *
   6  * @Author "Ashar Voultoiz" <hashar@altern.org>
   7  * @License GPL v2 or later
   8  */
   9
  10 // Some regex definition to "play" with IP address and IP address blocks
  11
  12 // An IP is made of 4 bytes from x00 to xFF which is d0 to d255
  13 define( 'RE_IP_BYTE', '(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|0?[0-9]?[0-9])');
  14 define( 'RE_IP_ADD' , RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE );
  15 // An IPv4 block is an IP address and a prefix (d1 to d32)
  16 define( 'RE_IP_PREFIX', '(3[0-2]|[12]?\d)');
  17 define( 'RE_IP_BLOCK', RE_IP_ADD . '\/' . RE_IP_PREFIX);
  18 // For IPv6 canonicalization (NOT for strict validation; these are quite lax!)
  19 define( 'RE_IPV6_WORD', '([0-9A-Fa-f]{1,4})' );
  20 define( 'RE_IPV6_GAP', ':(?:0+:)*(?::(?:0+:)*)?' );
  21 define( 'RE_IPV6_V4_PREFIX', '0*' . RE_IPV6_GAP . '(?:ffff:)?' );
  22 // An IPv6 block is an IP address and a prefix (d1 to d128)
  23 define( 'RE_IPV6_PREFIX', '(12[0-8]|1[01][0-9]|[1-9]?\d)');
  24 // An IPv6 IP is made up of 8 octets. However abbreviations like "::" can be used. This is lax!
  25 define( 'RE_IPV6_ADD', RE_IPV6_WORD . '(:{1,2}' . RE_IPV6_WORD . '|::$){1,7}' );
  26 define( 'RE_IPV6_BLOCK', RE_IPV6_ADD . '\/' . RE_IPV6_PREFIX );
  27 // This might be useful for regexps used elsewhere, matches any IPv6 or IPv6 address or network
  28 define( 'IP_ADDRESS_STRING', RE_IP_ADD . '(\/' . RE_IP_PREFIX . '|)|' . RE_IPV6_ADD . '(\/' . RE_IPV6_PREFIX . '|)');
  29
  30 class IP {
  31         /**
  32          * Given a string, determine if it as valid IP
  33          * Unlike isValid(), this looks for networks too
  34          * @param $ip IP address.
  35          * @return string
  36          */
  37         public function isIPAddress( $ip ) {
  38                 if ( !$ip ) return false;
  39                 return preg_match( '/^' . IP_ADDRESS_STRING . '$/', $ip);
  40         }
  41
  42         public function isIPv6( $ip ) {
  43                 return preg_match( '/^' . RE_IPV6_ADD . '(\/' . RE_IPV6_PREFIX . '|)$/', $ip);
  44         }
  45
  46         public function isIPv4( $ip ) {
  47                 return preg_match( '/^' . RE_IP_ADD . '(\/' . RE_IP_PREFIX . '|)$/', $ip);
  48         }
  49
  50         /**
  51          * Given an IP address in dotted-quad notation, returns an IPv6 octet.
  52          * See http://www.answers.com/topic/ipv4-compatible-address
  53          * IPs with the first 92 bits as zeros are reserved from IPv6
  54          * @param $ip quad-dotted IP address.
  55          * @return string
  56          */
  57         public function IPv4toIPv6( $ip ) {
  58                 if ( !$ip ) return null;
  59                 // Convert only if needed
  60                 if ( self::isIPv6( $ip ) ) return $ip;
  61                 // IPv4 CIDRs
  62                 if ( strpos( $ip, '/' ) !== false ) {
  63                         $parts = explode( '/', $ip, 2 );
  64                         if ( count( $parts ) != 2 ) {
  65                                 return false;
  66                         }
  67                         $network = self::toUnsigned( $parts[0] );
  68                         $bits = $parts[1] + 96;
  69                         if ( $network !== false && is_numeric( $parts[1] ) && $parts[1] >= 0 && $parts[1] <= 32 ) {
  70                                 return self::toOctet( $network ) . "/$bits";
  71                         } else {
  72                                 return false;
  73                         }
  74                 }
  75                 return self::toOctet( self::toUnsigned( $ip ) );
  76         }
  77
  78         /**
  79          * Given an IPv6 address in octet notation, returns an unsigned integer.
  80          * @param $ip octet ipv6 IP address.
  81          * @return string
  82          */
  83         public function toUnsigned6( $ip ) {
  84                 if ( !$ip ) return null;
  85         $ip = explode(':', self::expandIP( $ip ) );
  86         $r_ip = '';
  87         foreach ($ip as $v) {
  88                 $r_ip .= wfBaseConvert( $v, 16, 2, 16);
  89         }
  90         return wfBaseConvert($r_ip, 2, 10);
  91         }
  92
  93         /**
  94          * Given an IPv6 address in octet notation, returns the expanded octet.
  95          * @param $ip octet ipv6 IP address.
  96          * @return string
  97          */
  98         public function expandIP( $ip ) {
  99                 if ( !$ip ) return null;
 100                 // Only IPv6 addresses can be expanded
 101                 if ( !self::isIPv6( $ip ) ) return $ip;
 102                 // Expand zero abbreviations
 103                 if ( substr_count($ip, '::') ) {
 104                 $ip = str_replace('::', str_repeat(':0000', 8 - substr_count($ip, ':')) . ':', $ip);
 105         }
 106         return $ip;
 107         }
 108
 109         /**
 110          * Given an unsigned integer, returns an IPv6 address in octet notation
 111          * @param $ip integer ipv6 IP address.
 112          * @return string
 113          */
 114         public function toOctet( $ip_int ) {
 115                 // Convert integer to binary
 116                 $ip_int = wfBaseConvert($ip_int, 10, 2, 128);
 117                 // Seperate into 8 octets
 118                 $ip_oct = base_convert( substr( $ip_int, 0, 16 ), 2, 16 );
 119                 for ($n=1; $n < 8; $n++) {
 120                         // Convert to hex, and add ":" marks
 121                         $ip_oct .= ':' . base_convert( substr($ip_int, 16*$n, 16), 2, 16 );
 122                 }
 123         return $ip_oct;
 124         }
 125
 126         /**
 127          * Convert a network specification in IPv6 CIDR notation to an integer network and a number of bits
 128          * @return array(string, int)
 129          */
 130         public static function parseCIDR6( $range ) {
 131                 $parts = explode( '/', $range, 2 );
 132                 if ( count( $parts ) != 2 ) {
 133                         return array( false, false );
 134                 }
 135                 $network = self::toUnsigned6( $parts[0] );
 136                 if ( $network !== false && is_numeric( $parts[1] ) && $parts[1] >= 0 && $parts[1] <= 128 ) {
 137                         $bits = $parts[1];
 138                         if ( $bits == 0 ) {
 139                                 $network = 0;
 140                         } else {
 141                         # Native 32 bit functions WONT work here!!!
 142                         # Convert to a padded binary number
 143                                 $network = wfBaseConvert( $network, 10, 2, 128 );
 144                         # Truncate the last (128-$bits) bits and replace them with zeros
 145                                 $network = str_pad( substr( $network, 0, $bits ), 128, 0, STR_PAD_RIGHT );
 146                         # Convert back to an integer
 147                                 $network = wfBaseConvert( $network, 2, 10 );
 148                         }
 149                 } else {
 150                         $network = false;
 151                         $bits = false;
 152                 }
 153
 154                 return array( $network, $bits );
 155         }
 156
 157         /**
 158          * Given a string range in a number of formats, return the start and end of
 159          * the range in hexadecimal. For IPv6.
 160          *
 161          * Formats are:
 162          *     2001:0db8:85a3::7344/96                                   CIDR
 163          *     2001:0db8:85a3::7344 - 2001:0db8:85a3::7344   Explicit range
 164          *     2001:0db8:85a3::7344/96                                   Single IP
 165          * @return array(string, int)
 166          */
 167         public static function parseRange6( $range ) {
 168                 if ( strpos( $range, '/' ) !== false ) {
 169                         # CIDR
 170                         list( $network, $bits ) = self::parseCIDR6( $range );
 171                         if ( $network === false ) {
 172                                 $start = $end = false;
 173                         } else {
 174                                 $start = sprintf( '%08X', $network );
 175                                 $end = sprintf( '%08X', $network + pow( 2, (128 - $bits) ) - 1 );
 176                         }
 177                 } elseif ( strpos( $range, '-' ) !== false ) {
 178                         # Explicit range
 179                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 180                         $start = self::toUnsigned6( $start ); $end = self::toUnsigned6( $end );
 181                         if ( $start > $end ) {
 182                                 $start = $end = false;
 183                         } else {
 184                                 $start = sprintf( '%08X', $start );
 185                                 $end = sprintf( '%08X', $end );
 186                         }
 187                 } else {
 188                         # Single IP
 189                         $start = $end = self::toHex( $range );
 190                 }
 191                 if ( $start === false || $end === false ) {
 192                         return array( false, false );
 193                 } else {
 194                         return array( $start, $end );
 195                 }
 196     }
 197
 198         /**
 199          * Validate an IP address.
 200          * @return boolean True if it is valid.
 201          */
 202         public static function isValid( $ip ) {
 203                 return ( preg_match( '/^' . RE_IP_ADD . '$/', $ip) || preg_match( '/^' . RE_IPV6_ADD . '$/', $ip) );
 204         }
 205
 206         /**
 207          * Validate an IP Block.
 208          * @return boolean True if it is valid.
 209          */
 210         public static function isValidBlock( $ipblock ) {
 211                 return ( count(self::toArray($ipblock)) == 1 + 5 );
 212         }
 213
 214         /**
 215          * Determine if an IP address really is an IP address, and if it is public,
 216          * i.e. not RFC 1918 or similar
 217          * Comes from ProxyTools.php
 218          */
 219         public static function isPublic( $ip ) {
 220                 $n = self::toUnsigned( $ip );
 221                 if ( !$n ) {
 222                         return false;
 223                 }
 224
 225                 // ip2long accepts incomplete addresses, as well as some addresses
 226                 // followed by garbage characters. Check that it's really valid.
 227                 if( $ip != long2ip( $n ) ) {
 228                         return false;
 229                 }
 230
 231                 static $privateRanges = false;
 232                 if ( !$privateRanges ) {
 233                         $privateRanges = array(
 234                                 array( '10.0.0.0',    '10.255.255.255' ),   # RFC 1918 (private)
 235                                 array( '172.16.0.0',  '172.31.255.255' ),   #     "
 236                                 array( '192.168.0.0', '192.168.255.255' ),  #     "
 237                                 array( '0.0.0.0',     '0.255.255.255' ),    # this network
 238                                 array( '127.0.0.0',   '127.255.255.255' ),  # loopback
 239                         );
 240                 }
 241
 242                 foreach ( $privateRanges as $r ) {
 243                         $start = self::toUnsigned( $r[0] );
 244                         $end = self::toUnsigned( $r[1] );
 245                         if ( $n >= $start && $n <= $end ) {
 246                                 return false;
 247                         }
 248                 }
 249                 return true;
 250         }
 251
 252         /**
 253          * Split out an IP block as an array of 4 bytes and a mask,
 254          * return false if it can't be determined
 255          *
 256          * @parameter $ip string A quad dotted IP address
 257          * @return array
 258          */
 259         public static function toArray( $ipblock ) {
 260                 $matches = array();
 261                 if(! preg_match( '/^' . RE_IP_ADD . '(?:\/(?:'.RE_IP_PREFIX.'))?' . '$/', $ipblock, $matches ) ) {
 262                         return false;
 263                 } else {
 264                         return $matches;
 265                 }
 266         }
 267
 268         /**
 269          * Return a zero-padded hexadecimal representation of an IP address.
 270          *
 271          * Hexadecimal addresses are used because they can easily be extended to
 272          * IPv6 support. To separate the ranges, the return value from this
 273          * function for an IPv6 address will be prefixed with "v6-", a non-
 274          * hexadecimal string which sorts after the IPv4 addresses.
 275          *
 276          * @param $ip Quad dotted IP address.
 277          * @return hexidecimal
 278          */
 279         public static function toHex( $ip ) {
 280                 // Use IPv6 function if we have an that sort of IP
 281                 $n = ( self::isIPv6($ip) ) ? self::toUnsigned6( $ip ) : self::toUnsigned( $ip );
 282                 if ( $n !== false ) {
 283                         $n = sprintf( '%08X', $n );
 284                 }
 285                 return $n;
 286         }
 287
 288         /**
 289          * Given an IP address in dotted-quad notation, returns an unsigned integer.
 290          * Like ip2long() except that it actually works and has a consistent error return value.
 291          * Comes from ProxyTools.php
 292          * @param $ip Quad dotted IP address.
 293          * @return integer
 294          */
 295         public static function toUnsigned( $ip ) {
 296                 // Use IPv6 function if we have an that sort of IP
 297                 if ( self::isIPv6( $ip ) ) {
 298                         return toUnsigned6( $ip );
 299                 }
 300                 if ( $ip == '255.255.255.255' ) {
 301                         $n = -1;
 302                 } else {
 303                         $n = ip2long( $ip );
 304                         if ( $n == -1 || $n === false ) { # Return value on error depends on PHP version
 305                                 $n = false;
 306                         }
 307                 }
 308                 if ( $n < 0 ) {
 309                         $n += pow( 2, 32 );
 310                 }
 311                 return $n;
 312         }
 313
 314         /**
 315          * Convert a dotted-quad IP to a signed integer
 316          * Returns false on failure
 317          */
 318         public static function toSigned( $ip ) {
 319                 if ( $ip == '255.255.255.255' ) {
 320                         $n = -1;
 321                 } else {
 322                         $n = ip2long( $ip );
 323                         if ( $n == -1 ) {
 324                                 $n = false;
 325                         }
 326                 }
 327                 return $n;
 328         }
 329
 330         /**
 331          * Convert a network specification in CIDR notation to an integer network and a number of bits
 332          * @return array(string, int)
 333          */
 334         public static function parseCIDR( $range ) {
 335                 $parts = explode( '/', $range, 2 );
 336                 if ( count( $parts ) != 2 ) {
 337                         return array( false, false );
 338                 }
 339                 $network = self::toSigned( $parts[0] );
 340                 if ( $network !== false && is_numeric( $parts[1] ) && $parts[1] >= 0 && $parts[1] <= 32 ) {
 341                         $bits = $parts[1];
 342                         if ( $bits == 0 ) {
 343                                 $network = 0;
 344                         } else {
 345                                 $network &= ~((1 << (32 - $bits)) - 1);
 346                         }
 347                         # Convert to unsigned
 348                         if ( $network < 0 ) {
 349                                 $network += pow( 2, 32 );
 350                         }
 351                 } else {
 352                         $network = false;
 353                         $bits = false;
 354                 }
 355                 return array( $network, $bits );
 356         }
 357
 358         /**
 359          * Given a string range in a number of formats, return the start and end of
 360          * the range in hexadecimal. For IPv4.
 361          *
 362          * Formats are:
 363          *     1.2.3.4/24          CIDR
 364          *     1.2.3.4 - 1.2.3.5   Explicit range
 365          *     1.2.3.4             Single IP
 366          * @return array(string, int)
 367          */
 368         public static function parseRange( $range ) {
 369                 // Use IPv6 function if we have an that sort of IP
 370                 if ( self::isIPv6( $ip ) ) {
 371                         return self::parseRange6( $range );
 372                 }
 373                 if ( strpos( $range, '/' ) !== false ) {
 374                         # CIDR
 375                         list( $network, $bits ) = self::parseCIDR( $range );
 376                         if ( $network === false ) {
 377                                 $start = $end = false;
 378                         } else {
 379                                 $start = sprintf( '%08X', $network );
 380                                 $end = sprintf( '%08X', $network + pow( 2, (32 - $bits) ) - 1 );
 381                         }
 382                 } elseif ( strpos( $range, '-' ) !== false ) {
 383                         # Explicit range
 384                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 385                         $start = self::toUnsigned( $start ); $end = self::toUnsigned( $end );
 386                         if ( $start > $end ) {
 387                                 $start = $end = false;
 388                         } else {
 389                                 $start = sprintf( '%08X', $start );
 390                                 $end = sprintf( '%08X', $end );
 391                         }
 392                 } else {
 393                         # Single IP
 394                         $start = $end = self::toHex( $range );
 395                 }
 396                 if ( $start === false || $end === false ) {
 397                         return array( false, false );
 398                 } else {
 399                         return array( $start, $end );
 400                 }
 401     }
 402
 403     /**
 404      * Determine if a given IPv4 address is in a given CIDR network
 405      * @param $addr The address to check against the given range.
 406      * @param $range The range to check the given address against.
 407      * @return bool Whether or not the given address is in the given range.
 408      */
 409     public static function isInRange( $addr, $range ) {
 410     // Convert to IPv6 if needed
 411         $unsignedIP = self::toUnsigned6( self::IPv4toIPv6($addr) );
 412         list( $start, $end ) = self::parseRange6( self::IPv4toIPv6($range) );
 413         return (($unsignedIP >= $start) && ($unsignedIP <= $end));
 414     }
 415
 416     /**
 417      * Convert some unusual representations of IPv4 addresses to their
 418      * canonical dotted quad representation.
 419      *
 420      * This currently only checks a few IPV4-to-IPv6 related cases.  More
 421      * unusual representations may be added later.
 422      *
 423      * @param $addr something that might be an IP address
 424      * @return valid dotted quad IPv4 address or null
 425      */
 426     public static function canonicalize( $addr ) {
 427         if ( self::isValid( $addr ) )
 428             return $addr;
 429
 430         // IPv6 loopback address
 431         $m = array();
 432         if ( preg_match( '/^0*' . RE_IPV6_GAP . '1$/', $addr, $m ) )
 433             return '127.0.0.1';
 434
 435         // IPv4-mapped and IPv4-compatible IPv6 addresses
 436         if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . '(' . RE_IP_ADD . ')$/i', $addr, $m ) )
 437             return $m[1];
 438         if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . RE_IPV6_WORD . ':' . RE_IPV6_WORD . '$/i', $addr, $m ) )
 439             return long2ip( ( hexdec( $m[1] ) << 16 ) + hexdec( $m[2] ) );
 440
 441         return null;  // give up
 442     }
 443 }
 444
 445 ?>