includes/libs/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>"
  22  */
  23
  24 use Wikimedia\IPSet;
  25
  26 // Some regex definition to "play" with IP address and IP address ranges
  27
  28 // An IPv4 address is made of 4 bytes from x00 to xFF which is d0 to d255
  29 define( 'RE_IP_BYTE', '(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|0?[0-9]?[0-9])' );
  30 define( 'RE_IP_ADD', RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE . '\.' . RE_IP_BYTE );
  31 // An IPv4 range is an IP address and a prefix (d1 to d32)
  32 define( 'RE_IP_PREFIX', '(3[0-2]|[12]?\d)' );
  33 define( 'RE_IP_RANGE', RE_IP_ADD . '\/' . RE_IP_PREFIX );
  34
  35 // An IPv6 address is made up of 8 words (each x0000 to xFFFF).
  36 // However, the "::" abbreviation can be used on consecutive x0000 words.
  37 define( 'RE_IPV6_WORD', '([0-9A-Fa-f]{1,4})' );
  38 define( 'RE_IPV6_PREFIX', '(12[0-8]|1[01][0-9]|[1-9]?\d)' );
  39 define( 'RE_IPV6_ADD',
  40         '(?:' . // starts with "::" (including "::")
  41                 ':(?::|(?::' . RE_IPV6_WORD . '){1,7})' .
  42         '|' . // ends with "::" (except "::")
  43                 RE_IPV6_WORD . '(?::' . RE_IPV6_WORD . '){0,6}::' .
  44         '|' . // contains one "::" in the middle (the ^ makes the test fail if none found)
  45                 RE_IPV6_WORD . '(?::((?(-1)|:))?' . RE_IPV6_WORD . '){1,6}(?(-2)|^)' .
  46         '|' . // contains no "::"
  47                 RE_IPV6_WORD . '(?::' . RE_IPV6_WORD . '){7}' .
  48         ')'
  49 );
  50 // An IPv6 range is an IP address and a prefix (d1 to d128)
  51 define( 'RE_IPV6_RANGE', RE_IPV6_ADD . '\/' . RE_IPV6_PREFIX );
  52 // For IPv6 canonicalization (NOT for strict validation; these are quite lax!)
  53 define( 'RE_IPV6_GAP', ':(?:0+:)*(?::(?:0+:)*)?' );
  54 define( 'RE_IPV6_V4_PREFIX', '0*' . RE_IPV6_GAP . '(?:ffff:)?' );
  55
  56 // This might be useful for regexps used elsewhere, matches any IPv4 or IPv6 address or network
  57 define( 'IP_ADDRESS_STRING',
  58         '(?:' .
  59                 RE_IP_ADD . '(?:\/' . RE_IP_PREFIX . ')?' . // IPv4
  60         '|' .
  61                 RE_IPV6_ADD . '(?:\/' . RE_IPV6_PREFIX . ')?' . // IPv6
  62         ')'
  63 );
  64
  65 /**
  66  * A collection of public static functions to play with IP address
  67  * and IP ranges.
  68  */
  69 class IP {
  70
  71         /**
  72          * Determine if a string is as valid IP address or network (CIDR prefix).
  73          * SIIT IPv4-translated addresses are rejected.
  74          * @note canonicalize() tries to convert translated addresses to IPv4.
  75          *
  76          * @param string $ip Possible IP address
  77          * @return bool
  78          */
  79         public static function isIPAddress( $ip ) {
  80                 return (bool)preg_match( '/^' . IP_ADDRESS_STRING . '$/', $ip );
  81         }
  82
  83         /**
  84          * Given a string, determine if it as valid IP in IPv6 only.
  85          * @note Unlike isValid(), this looks for networks too.
  86          *
  87          * @param string $ip Possible IP address
  88          * @return bool
  89          */
  90         public static function isIPv6( $ip ) {
  91                 return (bool)preg_match( '/^' . RE_IPV6_ADD . '(?:\/' . RE_IPV6_PREFIX . ')?$/', $ip );
  92         }
  93
  94         /**
  95          * Given a string, determine if it as valid IP in IPv4 only.
  96          * @note Unlike isValid(), this looks for networks too.
  97          *
  98          * @param string $ip Possible IP address
  99          * @return bool
 100          */
 101         public static function isIPv4( $ip ) {
 102                 return (bool)preg_match( '/^' . RE_IP_ADD . '(?:\/' . RE_IP_PREFIX . ')?$/', $ip );
 103         }
 104
 105         /**
 106          * Validate an IP address. Ranges are NOT considered valid.
 107          * SIIT IPv4-translated addresses are rejected.
 108          * @note canonicalize() tries to convert translated addresses to IPv4.
 109          *
 110          * @param string $ip
 111          * @return bool True if it is valid
 112          */
 113         public static function isValid( $ip ) {
 114                 return ( preg_match( '/^' . RE_IP_ADD . '$/', $ip )
 115                         || preg_match( '/^' . RE_IPV6_ADD . '$/', $ip ) );
 116         }
 117
 118         /**
 119          * Validate an IP range (valid address with a valid CIDR prefix).
 120          * SIIT IPv4-translated addresses are rejected.
 121          * @note canonicalize() tries to convert translated addresses to IPv4.
 122          *
 123          * @param string $ipRange
 124          * @return bool True if it is valid
 125          * @since 1.30
 126          */
 127         public static function isValidRange( $ipRange ) {
 128                 return ( preg_match( '/^' . RE_IPV6_RANGE . '$/', $ipRange )
 129                         || preg_match( '/^' . RE_IP_RANGE . '$/', $ipRange ) );
 130         }
 131
 132         /**
 133          * Convert an IP into a verbose, uppercase, normalized form.
 134          * Both IPv4 and IPv6 addresses are trimmed. Additionally,
 135          * IPv6 addresses in octet notation are expanded to 8 words;
 136          * IPv4 addresses have leading zeros, in each octet, removed.
 137          *
 138          * @param string $ip IP address in quad or octet form (CIDR or not).
 139          * @return string
 140          */
 141         public static function sanitizeIP( $ip ) {
 142                 $ip = trim( $ip );
 143                 if ( $ip === '' ) {
 144                         return null;
 145                 }
 146                 /* If not an IP, just return trimmed value, since sanitizeIP() is called
 147                  * in a number of contexts where usernames are supplied as input.
 148                  */
 149                 if ( !self::isIPAddress( $ip ) ) {
 150                         return $ip;
 151                 }
 152                 if ( self::isIPv4( $ip ) ) {
 153                         // Remove leading 0's from octet representation of IPv4 address
 154                         $ip = preg_replace( '!(?:^|(?<=\.))0+(?=[1-9]|0[./]|0$)!', '', $ip );
 155                         return $ip;
 156                 }
 157                 // Remove any whitespaces, convert to upper case
 158                 $ip = strtoupper( $ip );
 159                 // Expand zero abbreviations
 160                 $abbrevPos = strpos( $ip, '::' );
 161                 if ( $abbrevPos !== false ) {
 162                         // We know this is valid IPv6. Find the last index of the
 163                         // address before any CIDR number (e.g. "a:b:c::/24").
 164                         $CIDRStart = strpos( $ip, "/" );
 165                         $addressEnd = ( $CIDRStart !== false )
 166                                 ? $CIDRStart - 1
 167                                 : strlen( $ip ) - 1;
 168                         // If the '::' is at the beginning...
 169                         if ( $abbrevPos == 0 ) {
 170                                 $repeat = '0:';
 171                                 $extra = ( $ip == '::' ) ? '0' : ''; // for the address '::'
 172                                 $pad = 9; // 7+2 (due to '::')
 173                         // If the '::' is at the end...
 174                         } elseif ( $abbrevPos == ( $addressEnd - 1 ) ) {
 175                                 $repeat = ':0';
 176                                 $extra = '';
 177                                 $pad = 9; // 7+2 (due to '::')
 178                         // If the '::' is in the middle...
 179                         } else {
 180                                 $repeat = ':0';
 181                                 $extra = ':';
 182                                 $pad = 8; // 6+2 (due to '::')
 183                         }
 184                         $ip = str_replace( '::',
 185                                 str_repeat( $repeat, $pad - substr_count( $ip, ':' ) ) . $extra,
 186                                 $ip
 187                         );
 188                 }
 189                 // Remove leading zeros from each bloc as needed
 190                 $ip = preg_replace( '/(^|:)0+(' . RE_IPV6_WORD . ')/', '$1$2', $ip );
 191
 192                 return $ip;
 193         }
 194
 195         /**
 196          * Prettify an IP for display to end users.
 197          * This will make it more compact and lower-case.
 198          *
 199          * @param string $ip
 200          * @return string
 201          */
 202         public static function prettifyIP( $ip ) {
 203                 $ip = self::sanitizeIP( $ip ); // normalize (removes '::')
 204                 if ( self::isIPv6( $ip ) ) {
 205                         // Split IP into an address and a CIDR
 206                         if ( strpos( $ip, '/' ) !== false ) {
 207                                 list( $ip, $cidr ) = explode( '/', $ip, 2 );
 208                         } else {
 209                                 list( $ip, $cidr ) = [ $ip, '' ];
 210                         }
 211                         // Get the largest slice of words with multiple zeros
 212                         $offset = 0;
 213                         $longest = $longestPos = false;
 214                         while ( preg_match(
 215                                 '!(?:^|:)0(?::0)+(?:$|:)!', $ip, $m, PREG_OFFSET_CAPTURE, $offset
 216                         ) ) {
 217                                 list( $match, $pos ) = $m[0]; // full match
 218                                 if ( strlen( $match ) > strlen( $longest ) ) {
 219                                         $longest = $match;
 220                                         $longestPos = $pos;
 221                                 }
 222                                 $offset = ( $pos + strlen( $match ) ); // advance
 223                         }
 224                         if ( $longest !== false ) {
 225                                 // Replace this portion of the string with the '::' abbreviation
 226                                 $ip = substr_replace( $ip, '::', $longestPos, strlen( $longest ) );
 227                         }
 228                         // Add any CIDR back on
 229                         if ( $cidr !== '' ) {
 230                                 $ip = "{$ip}/{$cidr}";
 231                         }
 232                         // Convert to lower case to make it more readable
 233                         $ip = strtolower( $ip );
 234                 }
 235
 236                 return $ip;
 237         }
 238
 239         /**
 240          * Given a host/port string, like one might find in the host part of a URL
 241          * per RFC 2732, split the hostname part and the port part and return an
 242          * array with an element for each. If there is no port part, the array will
 243          * have false in place of the port. If the string was invalid in some way,
 244          * false is returned.
 245          *
 246          * This was easy with IPv4 and was generally done in an ad-hoc way, but
 247          * with IPv6 it's somewhat more complicated due to the need to parse the
 248          * square brackets and colons.
 249          *
 250          * A bare IPv6 address is accepted despite the lack of square brackets.
 251          *
 252          * @param string $both The string with the host and port
 253          * @return array|false Array normally, false on certain failures
 254          */
 255         public static function splitHostAndPort( $both ) {
 256                 if ( substr( $both, 0, 1 ) === '[' ) {
 257                         if ( preg_match( '/^\[(' . RE_IPV6_ADD . ')\](?::(?P<port>\d+))?$/', $both, $m ) ) {
 258                                 if ( isset( $m['port'] ) ) {
 259                                         return [ $m[1], intval( $m['port'] ) ];
 260                                 } else {
 261                                         return [ $m[1], false ];
 262                                 }
 263                         } else {
 264                                 // Square bracket found but no IPv6
 265                                 return false;
 266                         }
 267                 }
 268                 $numColons = substr_count( $both, ':' );
 269                 if ( $numColons >= 2 ) {
 270                         // Is it a bare IPv6 address?
 271                         if ( preg_match( '/^' . RE_IPV6_ADD . '$/', $both ) ) {
 272                                 return [ $both, false ];
 273                         } else {
 274                                 // Not valid IPv6, but too many colons for anything else
 275                                 return false;
 276                         }
 277                 }
 278                 if ( $numColons >= 1 ) {
 279                         // Host:port?
 280                         $bits = explode( ':', $both );
 281                         if ( preg_match( '/^\d+/', $bits[1] ) ) {
 282                                 return [ $bits[0], intval( $bits[1] ) ];
 283                         } else {
 284                                 // Not a valid port
 285                                 return false;
 286                         }
 287                 }
 288
 289                 // Plain hostname
 290                 return [ $both, false ];
 291         }
 292
 293         /**
 294          * Given a host name and a port, combine them into host/port string like
 295          * you might find in a URL. If the host contains a colon, wrap it in square
 296          * brackets like in RFC 2732. If the port matches the default port, omit
 297          * the port specification
 298          *
 299          * @param string $host
 300          * @param int $port
 301          * @param bool|int $defaultPort
 302          * @return string
 303          */
 304         public static function combineHostAndPort( $host, $port, $defaultPort = false ) {
 305                 if ( strpos( $host, ':' ) !== false ) {
 306                         $host = "[$host]";
 307                 }
 308                 if ( $defaultPort !== false && $port == $defaultPort ) {
 309                         return $host;
 310                 } else {
 311                         return "$host:$port";
 312                 }
 313         }
 314
 315         /**
 316          * Convert an IPv4 or IPv6 hexadecimal representation back to readable format
 317          *
 318          * @param string $hex Number, with "v6-" prefix if it is IPv6
 319          * @return string Quad-dotted (IPv4) or octet notation (IPv6)
 320          */
 321         public static function formatHex( $hex ) {
 322                 if ( substr( $hex, 0, 3 ) == 'v6-' ) { // IPv6
 323                         return self::hexToOctet( substr( $hex, 3 ) );
 324                 } else { // IPv4
 325                         return self::hexToQuad( $hex );
 326                 }
 327         }
 328
 329         /**
 330          * Converts a hexadecimal number to an IPv6 address in octet notation
 331          *
 332          * @param string $ip_hex Pure hex (no v6- prefix)
 333          * @return string (of format a:b:c:d:e:f:g:h)
 334          */
 335         public static function hexToOctet( $ip_hex ) {
 336                 // Pad hex to 32 chars (128 bits)
 337                 $ip_hex = str_pad( strtoupper( $ip_hex ), 32, '0', STR_PAD_LEFT );
 338                 // Separate into 8 words
 339                 $ip_oct = substr( $ip_hex, 0, 4 );
 340                 for ( $n = 1; $n < 8; $n++ ) {
 341                         $ip_oct .= ':' . substr( $ip_hex, 4 * $n, 4 );
 342                 }
 343                 // NO leading zeroes
 344                 $ip_oct = preg_replace( '/(^|:)0+(' . RE_IPV6_WORD . ')/', '$1$2', $ip_oct );
 345
 346                 return $ip_oct;
 347         }
 348
 349         /**
 350          * Converts a hexadecimal number to an IPv4 address in quad-dotted notation
 351          *
 352          * @param string $ip_hex Pure hex
 353          * @return string (of format a.b.c.d)
 354          */
 355         public static function hexToQuad( $ip_hex ) {
 356                 // Pad hex to 8 chars (32 bits)
 357                 $ip_hex = str_pad( strtoupper( $ip_hex ), 8, '0', STR_PAD_LEFT );
 358                 // Separate into four quads
 359                 $s = '';
 360                 for ( $i = 0; $i < 4; $i++ ) {
 361                         if ( $s !== '' ) {
 362                                 $s .= '.';
 363                         }
 364                         $s .= base_convert( substr( $ip_hex, $i * 2, 2 ), 16, 10 );
 365                 }
 366
 367                 return $s;
 368         }
 369
 370         /**
 371          * Determine if an IP address really is an IP address, and if it is public,
 372          * i.e. not RFC 1918 or similar
 373          *
 374          * @param string $ip
 375          * @return bool
 376          */
 377         public static function isPublic( $ip ) {
 378                 static $privateSet = null;
 379                 if ( !$privateSet ) {
 380                         $privateSet = new IPSet( [
 381                                 '10.0.0.0/8', # RFC 1918 (private)
 382                                 '172.16.0.0/12', # RFC 1918 (private)
 383                                 '192.168.0.0/16', # RFC 1918 (private)
 384                                 '0.0.0.0/8', # this network
 385                                 '127.0.0.0/8', # loopback
 386                                 'fc00::/7', # RFC 4193 (local)
 387                                 '0:0:0:0:0:0:0:1', # loopback
 388                                 '169.254.0.0/16', # link-local
 389                                 'fe80::/10', # link-local
 390                         ] );
 391                 }
 392                 return !$privateSet->match( $ip );
 393         }
 394
 395         /**
 396          * Return a zero-padded upper case hexadecimal representation of an IP address.
 397          *
 398          * Hexadecimal addresses are used because they can easily be extended to
 399          * IPv6 support. To separate the ranges, the return value from this
 400          * function for an IPv6 address will be prefixed with "v6-", a non-
 401          * hexadecimal string which sorts after the IPv4 addresses.
 402          *
 403          * @param string $ip Quad dotted/octet IP address.
 404          * @return string|bool False on failure
 405          */
 406         public static function toHex( $ip ) {
 407                 if ( self::isIPv6( $ip ) ) {
 408                         $n = 'v6-' . self::IPv6ToRawHex( $ip );
 409                 } elseif ( self::isIPv4( $ip ) ) {
 410                         // T62035/T97897: An IP with leading 0's fails in ip2long sometimes (e.g. *.08),
 411                         // also double/triple 0 needs to be changed to just a single 0 for ip2long.
 412                         $ip = self::sanitizeIP( $ip );
 413                         $n = ip2long( $ip );
 414                         if ( $n < 0 ) {
 415                                 $n += 2 ** 32;
 416                                 # On 32-bit platforms (and on Windows), 2^32 does not fit into an int,
 417                                 # so $n becomes a float. We convert it to string instead.
 418                                 if ( is_float( $n ) ) {
 419                                         $n = (string)$n;
 420                                 }
 421                         }
 422                         if ( $n !== false ) {
 423                                 # Floating points can handle the conversion; faster than Wikimedia\base_convert()
 424                                 $n = strtoupper( str_pad( base_convert( $n, 10, 16 ), 8, '0', STR_PAD_LEFT ) );
 425                         }
 426                 } else {
 427                         $n = false;
 428                 }
 429
 430                 return $n;
 431         }
 432
 433         /**
 434          * Given an IPv6 address in octet notation, returns a pure hex string.
 435          *
 436          * @param string $ip Octet ipv6 IP address.
 437          * @return string|bool Pure hex (uppercase); false on failure
 438          */
 439         private static function IPv6ToRawHex( $ip ) {
 440                 $ip = self::sanitizeIP( $ip );
 441                 if ( !$ip ) {
 442                         return false;
 443                 }
 444                 $r_ip = '';
 445                 foreach ( explode( ':', $ip ) as $v ) {
 446                         $r_ip .= str_pad( $v, 4, 0, STR_PAD_LEFT );
 447                 }
 448
 449                 return $r_ip;
 450         }
 451
 452         /**
 453          * Convert a network specification in CIDR notation
 454          * to an integer network and a number of bits
 455          *
 456          * @param string $range IP with CIDR prefix
 457          * @return array [int or string, int]
 458          */
 459         public static function parseCIDR( $range ) {
 460                 if ( self::isIPv6( $range ) ) {
 461                         return self::parseCIDR6( $range );
 462                 }
 463                 $parts = explode( '/', $range, 2 );
 464                 if ( count( $parts ) != 2 ) {
 465                         return [ false, false ];
 466                 }
 467                 list( $network, $bits ) = $parts;
 468                 $network = ip2long( $network );
 469                 if ( $network !== false && is_numeric( $bits ) && $bits >= 0 && $bits <= 32 ) {
 470                         if ( $bits == 0 ) {
 471                                 $network = 0;
 472                         } else {
 473                                 $network &= ~( ( 1 << ( 32 - $bits ) ) - 1 );
 474                         }
 475                         # Convert to unsigned
 476                         if ( $network < 0 ) {
 477                                 $network += 2 ** 32;
 478                         }
 479                 } else {
 480                         $network = false;
 481                         $bits = false;
 482                 }
 483
 484                 return [ $network, $bits ];
 485         }
 486
 487         /**
 488          * Given a string range in a number of formats,
 489          * return the start and end of the range in hexadecimal.
 490          *
 491          * Formats are:
 492          *     1.2.3.4/24          CIDR
 493          *     1.2.3.4 - 1.2.3.5   Explicit range
 494          *     1.2.3.4             Single IP
 495          *
 496          *     2001:0db8:85a3::7344/96                       CIDR
 497          *     2001:0db8:85a3::7344 - 2001:0db8:85a3::7344   Explicit range
 498          *     2001:0db8:85a3::7344                          Single IP
 499          * @param string $range IP range
 500          * @return array [ string, string ]
 501          */
 502         public static function parseRange( $range ) {
 503                 // CIDR notation
 504                 if ( strpos( $range, '/' ) !== false ) {
 505                         if ( self::isIPv6( $range ) ) {
 506                                 return self::parseRange6( $range );
 507                         }
 508                         list( $network, $bits ) = self::parseCIDR( $range );
 509                         if ( $network === false ) {
 510                                 $start = $end = false;
 511                         } else {
 512                                 $start = sprintf( '%08X', $network );
 513                                 $end = sprintf( '%08X', $network + 2 ** ( 32 - $bits ) - 1 );
 514                         }
 515                 // Explicit range
 516                 } elseif ( strpos( $range, '-' ) !== false ) {
 517                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 518                         if ( self::isIPv6( $start ) && self::isIPv6( $end ) ) {
 519                                 return self::parseRange6( $range );
 520                         }
 521                         if ( self::isIPv4( $start ) && self::isIPv4( $end ) ) {
 522                                 $start = self::toHex( $start );
 523                                 $end = self::toHex( $end );
 524                                 if ( $start > $end ) {
 525                                         $start = $end = false;
 526                                 }
 527                         } else {
 528                                 $start = $end = false;
 529                         }
 530                 } else {
 531                         # Single IP
 532                         $start = $end = self::toHex( $range );
 533                 }
 534                 if ( $start === false || $end === false ) {
 535                         return [ false, false ];
 536                 } else {
 537                         return [ $start, $end ];
 538                 }
 539         }
 540
 541         /**
 542          * Convert a network specification in IPv6 CIDR notation to an
 543          * integer network and a number of bits
 544          *
 545          * @param string $range
 546          *
 547          * @return array [string, int]
 548          */
 549         private static function parseCIDR6( $range ) {
 550                 # Explode into <expanded IP,range>
 551                 $parts = explode( '/', self::sanitizeIP( $range ), 2 );
 552                 if ( count( $parts ) != 2 ) {
 553                         return [ false, false ];
 554                 }
 555                 list( $network, $bits ) = $parts;
 556                 $network = self::IPv6ToRawHex( $network );
 557                 if ( $network !== false && is_numeric( $bits ) && $bits >= 0 && $bits <= 128 ) {
 558                         if ( $bits == 0 ) {
 559                                 $network = "0";
 560                         } else {
 561                                 # Native 32 bit functions WONT work here!!!
 562                                 # Convert to a padded binary number
 563                                 $network = Wikimedia\base_convert( $network, 16, 2, 128 );
 564                                 # Truncate the last (128-$bits) bits and replace them with zeros
 565                                 $network = str_pad( substr( $network, 0, $bits ), 128, 0, STR_PAD_RIGHT );
 566                                 # Convert back to an integer
 567                                 $network = Wikimedia\base_convert( $network, 2, 10 );
 568                         }
 569                 } else {
 570                         $network = false;
 571                         $bits = false;
 572                 }
 573
 574                 return [ $network, (int)$bits ];
 575         }
 576
 577         /**
 578          * Given a string range in a number of formats, return the
 579          * start and end of the range in hexadecimal. For IPv6.
 580          *
 581          * Formats are:
 582          *     2001:0db8:85a3::7344/96                       CIDR
 583          *     2001:0db8:85a3::7344 - 2001:0db8:85a3::7344   Explicit range
 584          *     2001:0db8:85a3::7344/96                       Single IP
 585          *
 586          * @param string $range
 587          *
 588          * @return array [string, string]
 589          */
 590         private static function parseRange6( $range ) {
 591                 # Expand any IPv6 IP
 592                 $range = self::sanitizeIP( $range );
 593                 // CIDR notation...
 594                 if ( strpos( $range, '/' ) !== false ) {
 595                         list( $network, $bits ) = self::parseCIDR6( $range );
 596                         if ( $network === false ) {
 597                                 $start = $end = false;
 598                         } else {
 599                                 $start = Wikimedia\base_convert( $network, 10, 16, 32, false );
 600                                 # Turn network to binary (again)
 601                                 $end = Wikimedia\base_convert( $network, 10, 2, 128 );
 602                                 # Truncate the last (128-$bits) bits and replace them with ones
 603                                 $end = str_pad( substr( $end, 0, $bits ), 128, 1, STR_PAD_RIGHT );
 604                                 # Convert to hex
 605                                 $end = Wikimedia\base_convert( $end, 2, 16, 32, false );
 606                                 # see toHex() comment
 607                                 $start = "v6-$start";
 608                                 $end = "v6-$end";
 609                         }
 610                 // Explicit range notation...
 611                 } elseif ( strpos( $range, '-' ) !== false ) {
 612                         list( $start, $end ) = array_map( 'trim', explode( '-', $range, 2 ) );
 613                         $start = self::toHex( $start );
 614                         $end = self::toHex( $end );
 615                         if ( $start > $end ) {
 616                                 $start = $end = false;
 617                         }
 618                 } else {
 619                         # Single IP
 620                         $start = $end = self::toHex( $range );
 621                 }
 622                 if ( $start === false || $end === false ) {
 623                         return [ false, false ];
 624                 } else {
 625                         return [ $start, $end ];
 626                 }
 627         }
 628
 629         /**
 630          * Determine if a given IPv4/IPv6 address is in a given CIDR network
 631          *
 632          * @param string $addr The address to check against the given range.
 633          * @param string $range The range to check the given address against.
 634          * @return bool Whether or not the given address is in the given range.
 635          *
 636          * @note This can return unexpected results for invalid arguments!
 637          *       Make sure you pass a valid IP address and IP range.
 638          */
 639         public static function isInRange( $addr, $range ) {
 640                 $hexIP = self::toHex( $addr );
 641                 list( $start, $end ) = self::parseRange( $range );
 642
 643                 return ( strcmp( $hexIP, $start ) >= 0 &&
 644                         strcmp( $hexIP, $end ) <= 0 );
 645         }
 646
 647         /**
 648          * Determines if an IP address is a list of CIDR a.b.c.d/n ranges.
 649          *
 650          * @since 1.25
 651          *
 652          * @param string $ip the IP to check
 653          * @param array $ranges the IP ranges, each element a range
 654          *
 655          * @return bool true if the specified adress belongs to the specified range; otherwise, false.
 656          */
 657         public static function isInRanges( $ip, $ranges ) {
 658                 foreach ( $ranges as $range ) {
 659                         if ( self::isInRange( $ip, $range ) ) {
 660                                 return true;
 661                         }
 662                 }
 663                 return false;
 664         }
 665
 666         /**
 667          * Convert some unusual representations of IPv4 addresses to their
 668          * canonical dotted quad representation.
 669          *
 670          * This currently only checks a few IPV4-to-IPv6 related cases.  More
 671          * unusual representations may be added later.
 672          *
 673          * @param string $addr Something that might be an IP address
 674          * @return string|null Valid dotted quad IPv4 address or null
 675          */
 676         public static function canonicalize( $addr ) {
 677                 // remove zone info (T37738)
 678                 $addr = preg_replace( '/\%.*/', '', $addr );
 679
 680                 if ( self::isValid( $addr ) ) {
 681                         return $addr;
 682                 }
 683                 // Turn mapped addresses from ::ce:ffff:1.2.3.4 to 1.2.3.4
 684                 if ( strpos( $addr, ':' ) !== false && strpos( $addr, '.' ) !== false ) {
 685                         $addr = substr( $addr, strrpos( $addr, ':' ) + 1 );
 686                         if ( self::isIPv4( $addr ) ) {
 687                                 return $addr;
 688                         }
 689                 }
 690                 // IPv6 loopback address
 691                 $m = [];
 692                 if ( preg_match( '/^0*' . RE_IPV6_GAP . '1$/', $addr, $m ) ) {
 693                         return '127.0.0.1';
 694                 }
 695                 // IPv4-mapped and IPv4-compatible IPv6 addresses
 696                 if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . '(' . RE_IP_ADD . ')$/i', $addr, $m ) ) {
 697                         return $m[1];
 698                 }
 699                 if ( preg_match( '/^' . RE_IPV6_V4_PREFIX . RE_IPV6_WORD .
 700                         ':' . RE_IPV6_WORD . '$/i', $addr, $m )
 701                 ) {
 702                         return long2ip( ( hexdec( $m[1] ) << 16 ) + hexdec( $m[2] ) );
 703                 }
 704
 705                 return null; // give up
 706         }
 707
 708         /**
 709          * Gets rid of unneeded numbers in quad-dotted/octet IP strings
 710          * For example, 127.111.113.151/24 -> 127.111.113.0/24
 711          * @param string $range IP address to normalize
 712          * @return string
 713          */
 714         public static function sanitizeRange( $range ) {
 715                 list( /*...*/, $bits ) = self::parseCIDR( $range );
 716                 list( $start, /*...*/ ) = self::parseRange( $range );
 717                 $start = self::formatHex( $start );
 718                 if ( $bits === false ) {
 719                         return $start; // wasn't actually a range
 720                 }
 721
 722                 return "$start/$bits";
 723         }
 724
 725         /**
 726          * Returns the subnet of a given IP
 727          *
 728          * @param string $ip
 729          * @return string|false
 730          */
 731         public static function getSubnet( $ip ) {
 732                 $matches = [];
 733                 $subnet = false;
 734                 if ( self::isIPv6( $ip ) ) {
 735                         $parts = self::parseRange( "$ip/64" );
 736                         $subnet = $parts[0];
 737                 } elseif ( preg_match( '/^(\d+\.\d+\.\d+)\.\d+$/', $ip, $matches ) ) {
 738                         // IPv4
 739                         $subnet = $matches[1];
 740                 }
 741                 return $subnet;
 742         }
 743 }