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Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
<?php

> declare(strict_types=1); namespace MaxMind\Db; >
> use ArgumentCountError;
use BadMethodCallException; use Exception; use InvalidArgumentException; use MaxMind\Db\Reader\Decoder; use MaxMind\Db\Reader\InvalidDatabaseException; use MaxMind\Db\Reader\Metadata; use MaxMind\Db\Reader\Util; use UnexpectedValueException; /** * Instances of this class provide a reader for the MaxMind DB format. IP * addresses can be looked up using the get method. */ class Reader {
> /** private static $DATA_SECTION_SEPARATOR_SIZE = 16; > * @var int private static $METADATA_START_MARKER = "\xAB\xCD\xEFMaxMind.com"; > */
private static $METADATA_START_MARKER_LENGTH = 14;
> /** private static $METADATA_MAX_SIZE = 131072; // 128 * 1024 = 128KB > * @var string > */
private $decoder;
> /** private $fileHandle; > * @var int private $fileSize; > */
< private static $METADATA_MAX_SIZE = 131072; // 128 * 1024 = 128KB
> /** > * @var int > */ > private static $METADATA_MAX_SIZE = 131072; // 128 * 1024 = 128KiB
private $metadata;
> /** > * @var Decoder /** > */
* Constructs a Reader for the MaxMind DB format. The file passed to it must
> /** * be a valid MaxMind DB file such as a GeoIp2 database file. > * @var resource * > */
* @param string $database
> /** * the MaxMind DB file to use > * @var int * > */
* @throws InvalidArgumentException for invalid database path or unknown arguments
> /** * @throws \MaxMind\Db\Reader\InvalidDatabaseException > * @var int * if the database is invalid or there is an error reading > */
* from it
> /** */ > * @var Metadata public function __construct($database) > */
< * @throws \MaxMind\Db\Reader\InvalidDatabaseException
> * @throws InvalidDatabaseException
< public function __construct($database)
> public function __construct(string $database)
< throw new InvalidArgumentException( < 'The constructor takes exactly one argument.'
> throw new ArgumentCountError( > sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
); }
< if (!is_readable($database)) {
> $fileHandle = @fopen($database, 'rb'); > if ($fileHandle === false) {
throw new InvalidArgumentException( "The file \"$database\" does not exist or is not readable." ); }
< $this->fileHandle = @fopen($database, 'rb'); < if ($this->fileHandle === false) { < throw new InvalidArgumentException( < "Error opening \"$database\"." < ); < } < $this->fileSize = @filesize($database); < if ($this->fileSize === false) {
> $this->fileHandle = $fileHandle; > > $fileSize = @filesize($database); > if ($fileSize === false) {
throw new UnexpectedValueException( "Error determining the size of \"$database\"." ); }
> $this->fileSize = $fileSize;
$start = $this->findMetadataStart($database); $metadataDecoder = new Decoder($this->fileHandle, $start);
< list($metadataArray) = $metadataDecoder->decode($start);
> [$metadataArray] = $metadataDecoder->decode($start);
$this->metadata = new Metadata($metadataArray); $this->decoder = new Decoder( $this->fileHandle, $this->metadata->searchTreeSize + self::$DATA_SECTION_SEPARATOR_SIZE ); $this->ipV4Start = $this->ipV4StartNode(); } /** * Retrieves the record for the IP address. * * @param string $ipAddress * the IP address to look up * * @throws BadMethodCallException if this method is called on a closed database * @throws InvalidArgumentException if something other than a single IP address is passed to the method * @throws InvalidDatabaseException * if the database is invalid or there is an error reading * from it * * @return mixed the record for the IP address */
< public function get($ipAddress)
> public function get(string $ipAddress)
{ if (\func_num_args() !== 1) {
< throw new InvalidArgumentException( < 'Method takes exactly one argument.'
> throw new ArgumentCountError( > sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
); }
< list($record) = $this->getWithPrefixLen($ipAddress);
> [$record] = $this->getWithPrefixLen($ipAddress);
return $record; } /** * Retrieves the record for the IP address and its associated network prefix length. * * @param string $ipAddress * the IP address to look up * * @throws BadMethodCallException if this method is called on a closed database * @throws InvalidArgumentException if something other than a single IP address is passed to the method * @throws InvalidDatabaseException * if the database is invalid or there is an error reading * from it * * @return array an array where the first element is the record and the * second the network prefix length for the record */
< public function getWithPrefixLen($ipAddress)
> public function getWithPrefixLen(string $ipAddress): array
{ if (\func_num_args() !== 1) {
< throw new InvalidArgumentException( < 'Method takes exactly one argument.'
> throw new ArgumentCountError( > sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
); } if (!\is_resource($this->fileHandle)) { throw new BadMethodCallException( 'Attempt to read from a closed MaxMind DB.' ); }
< if (!filter_var($ipAddress, FILTER_VALIDATE_IP)) { < throw new InvalidArgumentException( < "The value \"$ipAddress\" is not a valid IP address." < ); < } < < list($pointer, $prefixLen) = $this->findAddressInTree($ipAddress);
> [$pointer, $prefixLen] = $this->findAddressInTree($ipAddress);
if ($pointer === 0) { return [null, $prefixLen]; } return [$this->resolveDataPointer($pointer), $prefixLen]; }
< private function findAddressInTree($ipAddress)
> private function findAddressInTree(string $ipAddress): array
{
< $rawAddress = unpack('C*', inet_pton($ipAddress));
> $packedAddr = @inet_pton($ipAddress); > if ($packedAddr === false) { > throw new InvalidArgumentException( > "The value \"$ipAddress\" is not a valid IP address." > ); > } > > $rawAddress = unpack('C*', $packedAddr);
$bitCount = \count($rawAddress) * 8; // The first node of the tree is always node 0, at the beginning of the // value $node = 0; $metadata = $this->metadata; // Check if we are looking up an IPv4 address in an IPv6 tree. If this // is the case, we can skip over the first 96 nodes. if ($metadata->ipVersion === 6) { if ($bitCount === 32) { $node = $this->ipV4Start; } } elseif ($metadata->ipVersion === 4 && $bitCount === 128) { throw new InvalidArgumentException( "Error looking up $ipAddress. You attempted to look up an" . ' IPv6 address in an IPv4-only database.' ); } $nodeCount = $metadata->nodeCount; for ($i = 0; $i < $bitCount && $node < $nodeCount; ++$i) { $tempBit = 0xFF & $rawAddress[($i >> 3) + 1]; $bit = 1 & ($tempBit >> 7 - ($i % 8)); $node = $this->readNode($node, $bit); } if ($node === $nodeCount) { // Record is empty return [0, $i];
< } elseif ($node > $nodeCount) {
> } > if ($node > $nodeCount) {
// Record is a data pointer return [$node, $i]; }
< throw new InvalidDatabaseException('Something bad happened');
> > throw new InvalidDatabaseException( > 'Invalid or corrupt database. Maximum search depth reached without finding a leaf node' > );
}
< private function ipV4StartNode()
> private function ipV4StartNode(): int
{ // If we have an IPv4 database, the start node is the first node if ($this->metadata->ipVersion === 4) { return 0; } $node = 0; for ($i = 0; $i < 96 && $node < $this->metadata->nodeCount; ++$i) { $node = $this->readNode($node, 0); } return $node; }
< private function readNode($nodeNumber, $index)
> private function readNode(int $nodeNumber, int $index): int
{ $baseOffset = $nodeNumber * $this->metadata->nodeByteSize; switch ($this->metadata->recordSize) { case 24: $bytes = Util::read($this->fileHandle, $baseOffset + $index * 3, 3);
< list(, $node) = unpack('N', "\x00" . $bytes);
> [, $node] = unpack('N', "\x00" . $bytes);
return $node;
>
case 28: $bytes = Util::read($this->fileHandle, $baseOffset + 3 * $index, 4); if ($index === 0) { $middle = (0xF0 & \ord($bytes[3])) >> 4; } else { $middle = 0x0F & \ord($bytes[0]); }
< list(, $node) = unpack('N', \chr($middle) . substr($bytes, $index, 3));
> [, $node] = unpack('N', \chr($middle) . substr($bytes, $index, 3));
return $node;
>
case 32: $bytes = Util::read($this->fileHandle, $baseOffset + $index * 4, 4);
< list(, $node) = unpack('N', $bytes);
> [, $node] = unpack('N', $bytes);
return $node;
>
default: throw new InvalidDatabaseException( 'Unknown record size: ' . $this->metadata->recordSize ); } }
< private function resolveDataPointer($pointer)
> /** > * @return mixed > */ > private function resolveDataPointer(int $pointer)
{ $resolved = $pointer - $this->metadata->nodeCount + $this->metadata->searchTreeSize; if ($resolved >= $this->fileSize) { throw new InvalidDatabaseException( "The MaxMind DB file's search tree is corrupt" ); }
< list($data) = $this->decoder->decode($resolved);
> [$data] = $this->decoder->decode($resolved);
return $data; } /* * This is an extremely naive but reasonably readable implementation. There * are much faster algorithms (e.g., Boyer-Moore) for this if speed is ever * an issue, but I suspect it won't be. */
< private function findMetadataStart($filename)
> private function findMetadataStart(string $filename): int
{ $handle = $this->fileHandle; $fstat = fstat($handle); $fileSize = $fstat['size']; $marker = self::$METADATA_START_MARKER; $markerLength = self::$METADATA_START_MARKER_LENGTH; $minStart = $fileSize - min(self::$METADATA_MAX_SIZE, $fileSize); for ($offset = $fileSize - $markerLength; $offset >= $minStart; --$offset) { if (fseek($handle, $offset) !== 0) { break; } $value = fread($handle, $markerLength); if ($value === $marker) { return $offset + $markerLength; } }
>
throw new InvalidDatabaseException( "Error opening database file ($filename). " . 'Is this a valid MaxMind DB file?' ); } /** * @throws InvalidArgumentException if arguments are passed to the method * @throws BadMethodCallException if the database has been closed * * @return Metadata object for the database */
< public function metadata()
> public function metadata(): Metadata
{ if (\func_num_args()) {
< throw new InvalidArgumentException( < 'Method takes no arguments.'
> throw new ArgumentCountError( > sprintf('%s() expects exactly 0 parameters, %d given', __METHOD__, \func_num_args())
); } // Not technically required, but this makes it consistent with // C extension and it allows us to change our implementation later. if (!\is_resource($this->fileHandle)) { throw new BadMethodCallException( 'Attempt to read from a closed MaxMind DB.' ); }
< return $this->metadata;
> return clone $this->metadata;
} /** * Closes the MaxMind DB and returns resources to the system. * * @throws Exception * if an I/O error occurs */
< public function close()
> public function close(): void
{
> if (\func_num_args()) { if (!\is_resource($this->fileHandle)) { > throw new ArgumentCountError( throw new BadMethodCallException( > sprintf('%s() expects exactly 0 parameters, %d given', __METHOD__, \func_num_args()) 'Attempt to close a closed MaxMind DB.' > ); ); > } } >
fclose($this->fileHandle); } }