includes/utils/IP.php

   1 <?php
   2 /**
   3  * Functions and constants to play with IP addresses and ranges
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Antoine Musso "<hashar at free dot fr>", Aaron Schulz
  22  */
  23
  24 // Some regex definition to "play" with IP address and IP address blocks
  25
  26 // An IPv4 address is made of 4 bytes from x00 to xFF which is d0 to d255
  27 define( 'RE_IP_BYTE', '(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|0?[0-9]?[0-9])' );
  28 define( 'RE_IP_ADD', RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE );
  29 // An IPv4 block is an IP address and a prefix (d1 to d32)
  30 define( 'RE_IP_PREFIX', '(3[0-2]|[12]?\d)' );
  31 define( 'RE_IP_BLOCK', RE_IP_ADD . '\/' . RE_IP_PREFIX );
  32
  33 // An IPv6 address is made up of 8 words (each x0000 to xFFFF).
  34 // However, the "::" abbreviation can be used on consecutive x0000 words.
  35 define( 'RE_IPV6_WORD', '([0-9A-Fa-f]{1,4})' );
  36 define( 'RE_IPV6_PREFIX', '(12[0-8]|1[01][0-9]|[1-9]?\d)' );
  37 define( 'RE_IPV6_ADD',
  38         '(?:' . // starts with "::" (including "::")
  39                 ':(?::|(?::' . RE_IPV6_WORD . '){1,7})' .
  40         '|' . // ends with "::" (except "::")
  41                 RE_IPV6_WORD . '(?::' . RE_IPV6_WORD . '){0,6}::' .
  42         '|' . // contains one "::" in the middle (the ^ makes the test fail if none found)
  43                 RE_IPV6_WORD . '(?::((?(-1)|:))?' . RE_IPV6_WORD . '){1,6}(?(-2)|^)' .
  44         '|' . // contains no "::"
  45                 RE_IPV6_WORD . '(?::' . RE_IPV6_WORD . '){7}' .
  46         ')'
  47 );
  48 // An IPv6 block is an IP address and a prefix (d1 to d128)
  49 define( 'RE_IPV6_BLOCK', RE_IPV6_ADD . '\/' . RE_IPV6_PREFIX );
  50 // For IPv6 canonicalization (NOT for strict validation; these are quite lax!)
  51 define( 'RE_IPV6_GAP', ':(?:0+:)*(?::(?:0+:)*)?' );
  52 define( 'RE_IPV6_V4_PREFIX', '0*' . RE_IPV6_GAP . '(?:ffff:)?' );
  53
  54 // This might be useful for regexps used elsewhere, matches any IPv6 or IPv6 address or network
  55 define( 'IP_ADDRESS_STRING',
  56         '(?:' .
  57                 RE_IP_ADD . '(?:\/' . RE_IP_PREFIX . ')?' . // IPv4
  58         '|' .
  59                 RE_IPV6_ADD . '(?:\/' . RE_IPV6_PREFIX . ')?' . // IPv6
  60         ')'
  61 );
  62
  63 /**
  64  * A collection of public static functions to play with IP address
  65  * and IP blocks.
  66  */
  67 class IP {
  68         /**
  69          * Determine if a string is as valid IP address or network (CIDR prefix).
  70          * SIIT IPv4-translated addresses are rejected.
  71          * Note: canonicalize() tries to convert translated addresses to IPv4.
  72          *
  73          * @param string $ip possible IP address
  74          * @return Boolean
  75          */
  76         public static function isIPAddress( $ip ) {
  77                 return (bool)preg_match( '/^' . IP_ADDRESS_STRING . '$/', $ip );
  78         }
  79
  80         /**
  81          * Given a string, determine if it as valid IP in IPv6 only.
  82          * Note: Unlike isValid(), this looks for networks too.
  83          *
  84          * @param string $ip possible IP address
  85          * @return Boolean
  86          */
  87         public static function isIPv6( $ip ) {
  88                 return (bool)preg_match( '/^' . RE_IPV6_ADD . '(?:\/' . RE_IPV6_PREFIX . ')?$/', $ip );
  89         }
  90
  91         /**
  92          * Given a string, determine if it as valid IP in IPv4 only.
  93          * Note: Unlike isValid(), this looks for networks too.
  94          *
  95          * @param string $ip possible IP address
  96          * @return Boolean
  97          */
  98         public static function isIPv4( $ip ) {
  99                 return (bool)preg_match( '/^' . RE_IP_ADD . '(?:\/' . RE_IP_PREFIX . ')?$/', $ip );
 100         }
 101
 102         /**
 103          * Validate an IP address. Ranges are NOT considered valid.
 104          * SIIT IPv4-translated addresses are rejected.
 105          * Note: canonicalize() tries to convert translated addresses to IPv4.
 106          *
 107          * @param $ip String
 108          * @return Boolean: True if it is valid.
 109          */
 110         public static function isValid( $ip ) {
 111                 return ( preg_match( '/^' . RE_IP_ADD . '$/', $ip )
 112                         || preg_match( '/^' . RE_IPV6_ADD . '$/', $ip ) );
 113         }
 114
 115         /**
 116          * Validate an IP Block (valid address WITH a valid prefix).
 117          * SIIT IPv4-translated addresses are rejected.
 118          * Note: canonicalize() tries to convert translated addresses to IPv4.
 119          *
 120          * @param $ipblock String
 121          * @return Boolean: True if it is valid.
 122          */
 123         public static function isValidBlock( $ipblock ) {
 124                 return ( preg_match( '/^' . RE_IPV6_BLOCK . '$/', $ipblock )
 125                         || preg_match( '/^' . RE_IP_BLOCK . '$/', $ipblock ) );
 126         }
 127
 128         /**
 129          * Convert an IP into a verbose, uppercase, normalized form.
 130          * IPv6 addresses in octet notation are expanded to 8 words.
 131          * IPv4 addresses are just trimmed.
 132          *
 133          * @param string $ip IP address in quad or octet form (CIDR or not).
 134          * @return String
 135          */
 136         public static function sanitizeIP( $ip ) {
 137                 $ip = trim( $ip );
 138                 if ( $ip === '' ) {
 139                         return null;
 140                 }
 141                 if ( self::isIPv4( $ip ) || !self::isIPv6( $ip ) ) {
 142                         return $ip; // nothing else to do for IPv4 addresses or invalid ones
 143                 }
 144                 // Remove any whitespaces, convert to upper case
 145                 $ip = strtoupper( $ip );
 146                 // Expand zero abbreviations
 147                 $abbrevPos = strpos( $ip, '::' );
 148                 if ( $abbrevPos !== false ) {
 149                         // We know this is valid IPv6. Find the last index of the
 150                         // address before any CIDR number (e.g. "a:b:c::/24").
 151                         $CIDRStart = strpos( $ip, "/" );
 152                         $addressEnd = ( $CIDRStart !== false )
 153                                 ? $CIDRStart - 1
 154                                 : strlen( $ip ) - 1;
 155                         // If the '::' is at the beginning...
 156                         if ( $abbrevPos == 0 ) {
 157                                 $repeat = '0:';
 158                                 $extra = ( $ip == '::' ) ? '0' : ''; // for the address '::'
 159                                 $pad = 9; // 7+2 (due to '::')
 160                         // If the '::' is at the end...
 161                         } elseif ( $abbrevPos == ( $addressEnd - 1 ) ) {
 162                                 $repeat = ':0';
 163                                 $extra = '';
 164                                 $pad = 9; // 7+2 (due to '::')
 165                         // If the '::' is in the middle...
 166                         } else {
 167                                 $repeat = ':0';
 168                                 $extra = ':';
 169                                 $pad = 8; // 6+2 (due to '::')
 170                         }
 171                         $ip = str_replace( '::',
 172                                 str_repeat( $repeat, $pad - substr_count( $ip, ':' ) ) . $extra,
 173                                 $ip
 174                         );
 175                 }
 176                 // Remove leading zeros from each bloc as needed
 177                 $ip = preg_replace( '/(^|:)0+(' . RE_IPV6_WORD . ')/', '$1$2', $ip );
 178
 179                 return $ip;
 180         }
 181
 182         /**
 183          * Prettify an IP for display to end users.
 184          * This will make it more compact and lower-case.
 185          *
 186          * @param $ip string
 187          * @return string
 188          */
 189         public static function prettifyIP( $ip ) {
 190                 $ip = self::sanitizeIP( $ip ); // normalize (removes '::')
 191                 if ( self::isIPv6( $ip ) ) {
 192                         // Split IP into an address and a CIDR
 193                         if ( strpos( $ip, '/' ) !== false ) {
 194                                 list( $ip, $cidr ) = explode( '/', $ip, 2 );
 195                         } else {
 196                                 list( $ip, $cidr ) = array( $ip, '' );
 197                         }
 198                         // Get the largest slice of words with multiple zeros
 199                         $offset = 0;
 200                         $longest = $longestPos = false;
 201                         while ( preg_match(
 202                                 '!(?:^|:)0(?::0)+(?:$|:)!', $ip, $m, PREG_OFFSET_CAPTURE, $offset
 203                         ) ) {
 204                                 list( $match, $pos ) = $m[0]; // full match
 205                                 if ( strlen( $match ) > strlen( $longest ) ) {
 206                                         $longest = $match;
 207                                         $longestPos = $pos;
 208                                 }
 209                                 $offset = ( $pos + strlen( $match ) ); // advance
 210                         }
 211                         if ( $longest !== false ) {
 212                                 // Replace this portion of the string with the '::' abbreviation
 213                                 $ip = substr_replace( $ip, '::', $longestPos, strlen( $longest ) );
 214                         }
 215                         // Add any CIDR back on
 216                         if ( $cidr !== '' ) {
 217                                 $ip = "{$ip}/{$cidr}";
 218                         }
 219                         // Convert to lower case to make it more readable
 220                         $ip = strtolower( $ip );
 221                 }
 222
 223                 return $ip;
 224         }
 225
 226         /**
 227          * Given a host/port string, like one might find in the host part of a URL
 228          * per RFC 2732, split the hostname part and the port part and return an
 229          * array with an element for each. If there is no port part, the array will
 230          * have false in place of the port. If the string was invalid in some way,
 231          * false is returned.
 232          *
 233          * This was easy with IPv4 and was generally done in an ad-hoc way, but
 234          * with IPv6 it's somewhat more complicated due to the need to parse the
 235          * square brackets and colons.
 236          *
 237          * A bare IPv6 address is accepted despite the lack of square brackets.
 238          *
 239          * @param string $both The string with the host and port
 240          * @return array
 241          */
 242         public static function splitHostAndPort( $both ) {
 243                 if ( substr( $both, 0, 1 ) === '[' ) {
 244                         if ( preg_match( '/^\[(' . RE_IPV6_ADD . ')\](?::(?P<port>\d+))?$/', $both, $m ) ) {
 245                                 if ( isset( $m['port'] ) ) {
 246                                         return array( $m[1], intval( $m['port'] ) );
 247                                 } else {
 248                                         return array( $m[1], false );
 249                                 }
 250                         } else {
 251                                 // Square bracket found but no IPv6
 252                                 return false;
 253                         }
 254                 }
 255                 $numColons = substr_count( $both, ':' );
 256                 if ( $numColons >= 2 ) {
 257                         // Is it a bare IPv6 address?
 258                         if ( preg_match( '/^' . RE_IPV6_ADD . '$/', $both ) ) {
 259                                 return array( $both, false );
 260                         } else {
 261                                 // Not valid IPv6, but too many colons for anything else
 262                                 return false;
 263                         }
 264                 }
 265                 if ( $numColons >= 1 ) {
 266                         // Host:port?
 267                         $bits = explode( ':', $both );
 268                         if ( preg_match( '/^\d+/', $bits[1] ) ) {
 269                                 return array( $bits[0], intval( $bits[1] ) );
 270                         } else {
 271                                 // Not a valid port
 272                                 return false;
 273                         }
 274                 }
 275
 276                 // Plain hostname
 277                 return array( $both, false );
 278         }
 279
 280         /**
 281          * Given a host name and a port, combine them into host/port string like
 282          * you might find in a URL. If the host contains a colon, wrap it in square
 283          * brackets like in RFC 2732. If the port matches the default port, omit
 284          * the port specification
 285          *
 286          * @param $host string
 287          * @param $port int
 288          * @param $defaultPort bool|int
 289          * @return string
 290          */
 291         public static function combineHostAndPort( $host, $port, $defaultPort = false ) {
 292                 if ( strpos( $host, ':' ) !== false ) {
 293                         $host = "[$host]";
 294                 }
 295                 if ( $defaultPort !== false && $port == $defaultPort ) {
 296                         return $host;
 297                 } else {
 298                         return "$host:$port";
 299                 }
 300         }
 301
 302         /**
 303          * Given an unsigned integer, returns an IPv6 address in octet notation
 304          *
 305          * @param $ip_int String: IP address.
 306          * @return String
 307          */
 308         public static function toOctet( $ip_int ) {
 309                 return self::hexToOctet( wfBaseConvert( $ip_int, 10, 16, 32, false ) );
 310         }
 311
 312         /**
 313          * Convert an IPv4 or IPv6 hexadecimal representation back to readable format
 314          *
 315          * @param string $hex number, with "v6-" prefix if it is IPv6
 316          * @return String: quad-dotted (IPv4) or octet notation (IPv6)
 317          */
 318         public static function formatHex( $hex ) {
 319                 if ( substr( $hex, 0, 3 ) == 'v6-' ) { // IPv6
 320                         return self::hexToOctet( substr( $hex, 3 ) );
 321                 } else { // IPv4
 322                         return self::hexToQuad( $hex );
 323                 }
 324         }
 325
 326         /**
 327          * Converts a hexadecimal number to an IPv6 address in octet notation
 328          *
 329          * @param $ip_hex String: pure hex (no v6- prefix)
 330          * @return String (of format a:b:c:d:e:f:g:h)
 331          */
 332         public static function hexToOctet( $ip_hex ) {
 333                 // Pad hex to 32 chars (128 bits)
 334                 $ip_hex = str_pad( strtoupper( $ip_hex ), 32, '0', STR_PAD_LEFT );
 335                 // Separate into 8 words
 336                 $ip_oct = substr( $ip_hex, 0, 4 );
 337                 for ( $n = 1; $n < 8; $n++ ) {
 338                         $ip_oct .= ':' . substr( $ip_hex, 4 * $n, 4 );
 339                 }
 340                 // NO leading zeroes
 341                 $ip_oct = preg_replace( '/(^|:)0+(' . RE_IPV6_WORD . ')/', '$1$2', $ip_oct );
 342
 343                 return $ip_oct;
 344         }
 345
 346         /**
 347          * Converts a hexadecimal number to an IPv4 address in quad-dotted notation
 348          *
 349          * @param $ip_hex String: pure hex
 350          * @return String (of format a.b.c.d)
 351          */
 352         public static function hexToQuad( $ip_hex ) {
 353                 // Pad hex to 8 chars (32 bits)
 354                 $ip_hex = str_pad( strtoupper( $ip_hex ), 8, '0', STR_PAD_LEFT );
 355                 // Separate into four quads
 356                 $s = '';
 357                 for ( $i = 0; $i < 4; $i++ ) {
 358                         if ( $s !== '' ) {
 359                                 $s .= '.';
 360                         }
 361                         $s .= base_convert( substr( $ip_hex, $i * 2, 2 ), 16, 10 );
 362                 }
 363
 364                 return $s;
 365         }
 366
 367         /**
 368          * Determine if an IP address really is an IP address, and if it is public,
 369          * i.e. not RFC 1918 or similar
 370          *
 371          * @param $ip String
 372          * @return Boolean
 373          */
 374         public static function isPublic( $ip ) {
 375                 if ( self::isIPv6( $ip ) ) {
 376                         return self::isPublic6( $ip );
 377                 }
 378                 $n = self::toUnsigned( $ip );
 379                 if ( !$n ) {
 380                         return false;
 381                 }
 382
 383                 // ip2long accepts incomplete addresses, as well as some addresses
 384                 // followed by garbage characters. Check that it's really valid.
 385                 if ( $ip != long2ip( $n ) ) {
 386                         return false;
 387                 }
 388
 389                 static $privateRanges = false;
 390                 if ( !$privateRanges ) {
 391                         $privateRanges = array(
 392                                 array( '10.0.0.0', '10.255.255.255' ), # RFC 1918 (private)
 393                                 array( '172.16.0.0', '172.31.255.255' ), # RFC 1918 (private)
 394                                 array( '192.168.0.0', '192.168.255.255' ), # RFC 1918 (private)
 395                                 array( '0.0.0.0', '0.255.255.255' ), # this network
 396                                 array( '127.0.0.0', '127.255.255.255' ), # loopback
 397                         );
 398                 }
 399
 400                 foreach ( $privateRanges as $r ) {
 401                         $start = self::toUnsigned( $r[0] );
 402                         $end = self::toUnsigned( $r[1] );
 403                         if ( $n >= $start && $n <= $end ) {
 404                                 return false;
 405                         }
 406                 }
 407
 408                 return true;
 409         }
 410
 411         /**
 412          * Determine if an IPv6 address really is an IP address, and if it is public,
 413          * i.e. not RFC 4193 or similar
 414          *
 415          * @param $ip String
 416          * @return Boolean
 417          */
 418         private static function isPublic6( $ip ) {
 419                 static $privateRanges = false;
 420                 if ( !$privateRanges ) {
 421                         $privateRanges = array(
 422                                 array( 'fc00::', 'fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff' ), # RFC 4193 (local)
 423                                 array( '0:0:0:0:0:0:0:1', '0:0:0:0:0:0:0:1' ), # loopback
 424                         );
 425                 }
 426                 $n = self::toHex( $ip );
 427                 foreach ( $privateRanges as $r ) {
 428                         $start = self::toHex( $r[0] );
 429                         $end = self::toHex( $r[1] );
 430                         if ( $n >= $start && $n <= $end ) {
 431                                 return false;
 432                         }
 433                 }
 434
 435                 return true;
 436         }
 437
 438         /**
 439          * Return a zero-padded upper case hexadecimal representation of an IP address.
 440          *
 441          * Hexadecimal addresses are used because they can easily be extended to
 442          * IPv6 support. To separate the ranges, the return value from this
 443          * function for an IPv6 address will be prefixed with "v6-", a non-
 444          * hexadecimal string which sorts after the IPv4 addresses.
 445          *
 446          * @param string $ip quad dotted/octet IP address.
 447          * @return String
 448          */
 449         public static function toHex( $ip ) {
 450                 if ( self::isIPv6( $ip ) ) {
 451                         $n = 'v6-' . self::IPv6ToRawHex( $ip );
 452                 } else {
 453                         $n = self::toUnsigned( $ip );
 454                         if ( $n !== false ) {
 455                                 $n = wfBaseConvert( $n, 10, 16, 8, false );
 456                         }
 457                 }
 458
 459                 return $n;
 460         }
 461
 462         /**
 463          * Given an IPv6 address in octet notation, returns a pure hex string.
 464          *
 465          * @param string $ip octet ipv6 IP address.
 466          * @return String: pure hex (uppercase)
 467          */
 468         private static function IPv6ToRawHex( $ip ) {
 469                 $ip = self::sanitizeIP( $ip );
 470                 if ( !$ip ) {
 471                         return null;
 472                 }
 473                 $r_ip = '';
 474                 foreach ( explode( ':', $ip ) as $v ) {
 475                         $r_ip .= str_pad( $v, 4, 0, STR_PAD_LEFT );
 476                 }
 477
 478                 return $r_ip;
 479         }
 480
 481         /**
 482          * Given an IP address in dotted-quad/octet notation, returns an unsigned integer.
 483          * Like ip2long() except that it actually works and has a consistent error return value.
 484          *
 485          * @param string $ip quad dotted IP address.
 486          * @return Mixed: string/int/false
 487          */
 488         public static function toUnsigned( $ip ) {
 489                 if ( self::isIPv6( $ip ) ) {
 490                         $n = self::toUnsigned6( $ip );
 491                 } else {
 492                         // Bug 60035: an IP with leading 0's fails in ip2long sometimes (e.g. *.08)
 493                         $ip = preg_replace( '/(?<=\.)0+(?=[1-9])/', '', $ip );
 494                         $n = ip2long( $ip );
 495                         if ( $n < 0 ) {
 496                                 $n += pow( 2, 32 );
 497                                 # On 32-bit platforms (and on Windows), 2^32 does not fit into an int,
 498                                 # so $n becomes a float. We convert it to string instead.
 499                                 if ( is_float( $n ) ) {
 500                                         $n = (string)$n;
 501                                 }
 502                         }
 503                 }
 504
 505                 return $n;
 506         }
 507
 508         /**
 509          * @param $ip
 510          * @return String
 511          */
 512         private static function toUnsigned6( $ip ) {
 513                 return wfBaseConvert( self::IPv6ToRawHex( $ip ), 16, 10 );
 514         }
 515
 516         /**
 517          * Convert a network specification in CIDR notation
 518          * to an integer network and a number of bits
 519          *
 520          * @param string $range IP with CIDR prefix
 521          * @return array(int or string, int)
 522          */
 523         public static function parseCIDR( $range ) {
 524                 if ( self::isIPv6( $range ) ) {
 525                         return self::parseCIDR6( $range );
 526                 }
 527                 $parts = explode( '/', $range, 2 );
 528                 if ( count( $parts ) != 2 ) {
 529                         return array( false, false );
 530                 }
 531                 list( $network, $bits ) = $parts;
 532                 $network = ip2long( $network );
 533                 if ( $network !== false && is_numeric( $bits ) && $bits >= 0 && $bits <= 32 ) {
 534                         if ( $bits == 0 ) {
 535                                 $network = 0;
 536                         } else {
 537                                 $network &= ~( ( 1 << ( 32 - $bits ) ) - 1 );
 538                         }
 539                         # Convert to unsigned
 540                         if ( $network < 0 ) {
 541                                 $network += pow( 2, 32 );
 542                         }
 543                 } else {
 544                         $network = false;
 545                         $bits = false;
 546                 }
 547
 548                 return array( $network, $bits );
 549         }
 550
 551         /**
 552          * Given a string range in a number of formats,
 553          * return the start and end of the range in hexadecimal.
 554          *
 555          * Formats are:
 556          *     1.2.3.4/24          CIDR
 557          *     1.2.3.4 - 1.2.3.5   Explicit range
 558          *     1.2.3.4             Single IP
 559          *
 560          *     2001:0db8:85a3::7344/96                       CIDR
 561          *     2001:0db8:85a3::7344 - 2001:0db8:85a3::7344   Explicit range
 562          *     2001:0db8:85a3::7344                          Single IP
 563          * @param string $range IP range
 564          * @return array(string, string)
 565          */
 566         public static function parseRange( $range ) {
 567                 // CIDR notation
 568                 if ( strpos( $range, '/' ) !== false ) {
 569                         if ( self::isIPv6( $range ) ) {
 570                                 return self::parseRange6( $range );
 571                         }
 572                         list( $network, $bits ) = self::parseCIDR( $range );
 573                         if ( $network === false ) {
 574                                 $start = $end = false;
 575                         } else {
 576                                 $start = sprintf( '%08X', $network );
 577                                 $end = sprintf( '%08X', $network + pow( 2, ( 32 - $bits ) ) - 1 );
 578                         }
 579                 // Explicit range
 580                 } elseif ( strpos( $range, '-' ) !== false ) {
 581                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 582                         if ( self::isIPv6( $start ) && self::isIPv6( $end ) ) {
 583                                 return self::parseRange6( $range );
 584                         }
 585                         if ( self::isIPv4( $start ) && self::isIPv4( $end ) ) {
 586                                 $start = self::toUnsigned( $start );
 587                                 $end = self::toUnsigned( $end );
 588                                 if ( $start > $end ) {
 589                                         $start = $end = false;
 590                                 } else {
 591                                         $start = sprintf( '%08X', $start );
 592                                         $end = sprintf( '%08X', $end );
 593                                 }
 594                         } else {
 595                                 $start = $end = false;
 596                         }
 597                 } else {
 598                         # Single IP
 599                         $start = $end = self::toHex( $range );
 600                 }
 601                 if ( $start === false || $end === false ) {
 602                         return array( false, false );
 603                 } else {
 604                         return array( $start, $end );
 605                 }
 606         }
 607
 608         /**
 609          * Convert a network specification in IPv6 CIDR notation to an
 610          * integer network and a number of bits
 611          *
 612          * @param $range
 613          *
 614          * @return array(string, int)
 615          */
 616         private static function parseCIDR6( $range ) {
 617                 # Explode into <expanded IP,range>
 618                 $parts = explode( '/', IP::sanitizeIP( $range ), 2 );
 619                 if ( count( $parts ) != 2 ) {
 620                         return array( false, false );
 621                 }
 622                 list( $network, $bits ) = $parts;
 623                 $network = self::IPv6ToRawHex( $network );
 624                 if ( $network !== false && is_numeric( $bits ) && $bits >= 0 && $bits <= 128 ) {
 625                         if ( $bits == 0 ) {
 626                                 $network = "0";
 627                         } else {
 628                                 # Native 32 bit functions WONT work here!!!
 629                                 # Convert to a padded binary number
 630                                 $network = wfBaseConvert( $network, 16, 2, 128 );
 631                                 # Truncate the last (128-$bits) bits and replace them with zeros
 632                                 $network = str_pad( substr( $network, 0, $bits ), 128, 0, STR_PAD_RIGHT );
 633                                 # Convert back to an integer
 634                                 $network = wfBaseConvert( $network, 2, 10 );
 635                         }
 636                 } else {
 637                         $network = false;
 638                         $bits = false;
 639                 }
 640
 641                 return array( $network, (int)$bits );
 642         }
 643
 644         /**
 645          * Given a string range in a number of formats, return the
 646          * start and end of the range in hexadecimal. For IPv6.
 647          *
 648          * Formats are:
 649          *     2001:0db8:85a3::7344/96                       CIDR
 650          *     2001:0db8:85a3::7344 - 2001:0db8:85a3::7344   Explicit range
 651          *     2001:0db8:85a3::7344/96                       Single IP
 652          *
 653          * @param $range
 654          *
 655          * @return array(string, string)
 656          */
 657         private static function parseRange6( $range ) {
 658                 # Expand any IPv6 IP
 659                 $range = IP::sanitizeIP( $range );
 660                 // CIDR notation...
 661                 if ( strpos( $range, '/' ) !== false ) {
 662                         list( $network, $bits ) = self::parseCIDR6( $range );
 663                         if ( $network === false ) {
 664                                 $start = $end = false;
 665                         } else {
 666                                 $start = wfBaseConvert( $network, 10, 16, 32, false );
 667                                 # Turn network to binary (again)
 668                                 $end = wfBaseConvert( $network, 10, 2, 128 );
 669                                 # Truncate the last (128-$bits) bits and replace them with ones
 670                                 $end = str_pad( substr( $end, 0, $bits ), 128, 1, STR_PAD_RIGHT );
 671                                 # Convert to hex
 672                                 $end = wfBaseConvert( $end, 2, 16, 32, false );
 673                                 # see toHex() comment
 674                                 $start = "v6-$start";
 675                                 $end = "v6-$end";
 676                         }
 677         // Explicit range notation...
 678                 } elseif ( strpos( $range, '-' ) !== false ) {
 679                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 680                         $start = self::toUnsigned6( $start );
 681                         $end = self::toUnsigned6( $end );
 682                         if ( $start > $end ) {
 683                                 $start = $end = false;
 684                         } else {
 685                                 $start = wfBaseConvert( $start, 10, 16, 32, false );
 686                                 $end = wfBaseConvert( $end, 10, 16, 32, false );
 687                         }
 688                         # see toHex() comment
 689                         $start = "v6-$start";
 690                         $end = "v6-$end";
 691                 } else {
 692                         # Single IP
 693                         $start = $end = self::toHex( $range );
 694                 }
 695                 if ( $start === false || $end === false ) {
 696                         return array( false, false );
 697                 } else {
 698                         return array( $start, $end );
 699                 }
 700         }
 701
 702         /**
 703          * Determine if a given IPv4/IPv6 address is in a given CIDR network
 704          *
 705          * @param string $addr the address to check against the given range.
 706          * @param string $range the range to check the given address against.
 707          * @return Boolean: whether or not the given address is in the given range.
 708          */
 709         public static function isInRange( $addr, $range ) {
 710                 $hexIP = self::toHex( $addr );
 711                 list( $start, $end ) = self::parseRange( $range );
 712
 713                 return ( strcmp( $hexIP, $start ) >= 0 &&
 714                         strcmp( $hexIP, $end ) <= 0 );
 715         }
 716
 717         /**
 718          * Convert some unusual representations of IPv4 addresses to their
 719          * canonical dotted quad representation.
 720          *
 721          * This currently only checks a few IPV4-to-IPv6 related cases.  More
 722          * unusual representations may be added later.
 723          *
 724          * @param string $addr something that might be an IP address
 725          * @return String: valid dotted quad IPv4 address or null
 726          */
 727         public static function canonicalize( $addr ) {
 728                 // remove zone info (bug 35738)
 729                 $addr = preg_replace( '/\%.*/', '', $addr );
 730
 731                 if ( self::isValid( $addr ) ) {
 732                         return $addr;
 733                 }
 734                 // Turn mapped addresses from ::ce:ffff:1.2.3.4 to 1.2.3.4
 735                 if ( strpos( $addr, ':' ) !== false && strpos( $addr, '.' ) !== false ) {
 736                         $addr = substr( $addr, strrpos( $addr, ':' ) + 1 );
 737                         if ( self::isIPv4( $addr ) ) {
 738                                 return $addr;
 739                         }
 740                 }
 741                 // IPv6 loopback address
 742                 $m = array();
 743                 if ( preg_match( '/^0*' . RE_IPV6_GAP . '1$/', $addr, $m ) ) {
 744                         return '127.0.0.1';
 745                 }
 746                 // IPv4-mapped and IPv4-compatible IPv6 addresses
 747                 if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . '(' . RE_IP_ADD . ')$/i', $addr, $m ) ) {
 748                         return $m[1];
 749                 }
 750                 if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . RE_IPV6_WORD .
 751                         ':' . RE_IPV6_WORD . '$/i', $addr, $m )
 752                 ) {
 753                         return long2ip( ( hexdec( $m[1] ) << 16 ) + hexdec( $m[2] ) );
 754                 }
 755
 756                 return null; // give up
 757         }
 758
 759         /**
 760          * Gets rid of unneeded numbers in quad-dotted/octet IP strings
 761          * For example, 127.111.113.151/24 -> 127.111.113.0/24
 762          * @param string $range IP address to normalize
 763          * @return string
 764          */
 765         public static function sanitizeRange( $range ) {
 766                 list( /*...*/, $bits ) = self::parseCIDR( $range );
 767                 list( $start, /*...*/ ) = self::parseRange( $range );
 768                 $start = self::formatHex( $start );
 769                 if ( $bits === false ) {
 770                         return $start; // wasn't actually a range
 771                 }
 772
 773                 return "$start/$bits";
 774         }
 775 }