310 lines
10 KiB
PHP
310 lines
10 KiB
PHP
|
<?php
|
||
|
|
|
||
|
|
namespace MaxMind\Db;
|
||
|
|
|
||
|
|
use MaxMind\Db\Reader\Decoder;
|
||
|
|
use MaxMind\Db\Reader\InvalidDatabaseException;
|
||
|
|
use MaxMind\Db\Reader\Metadata;
|
||
|
|
use MaxMind\Db\Reader\Util;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Instances of this class provide a reader for the MaxMind DB format. IP
|
||
|
|
* addresses can be looked up using the <code>get</code> method.
|
||
|
|
*/
|
||
|
|
class Reader
|
||
|
|
{
|
||
|
|
private static $DATA_SECTION_SEPARATOR_SIZE = 16;
|
||
|
|
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
|
||
|
|
|
||
|
|
private $decoder;
|
||
|
|
private $fileHandle;
|
||
|
|
private $fileSize;
|
||
|
|
private $ipV4Start;
|
||
|
|
private $metadata;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
* @param string $database
|
||
|
|
* the MaxMind DB file to use
|
||
|
|
*
|
||
|
|
* @throws \InvalidArgumentException for invalid database path or unknown arguments
|
||
|
|
* @throws \MaxMind\Db\Reader\InvalidDatabaseException
|
||
|
|
* if the database is invalid or there is an error reading
|
||
|
|
* from it
|
||
|
|
*/
|
||
|
|
public function __construct($database)
|
||
|
|
{
|
||
|
|
if (func_num_args() !== 1) {
|
||
|
|
throw new \InvalidArgumentException(
|
||
|
|
'The constructor takes exactly one argument.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!is_readable($database)) {
|
||
|
|
throw new \InvalidArgumentException(
|
||
|
|
"The file \"$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 ($this->fileSize === false) {
|
||
|
|
throw new \UnexpectedValueException(
|
||
|
|
"Error determining the size of \"$database\"."
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
$start = $this->findMetadataStart($database);
|
||
|
|
$metadataDecoder = new Decoder($this->fileHandle, $start);
|
||
|
|
list($metadataArray) = $metadataDecoder->decode($start);
|
||
|
|
$this->metadata = new Metadata($metadataArray);
|
||
|
|
$this->decoder = new Decoder(
|
||
|
|
$this->fileHandle,
|
||
|
|
$this->metadata->searchTreeSize + self::$DATA_SECTION_SEPARATOR_SIZE
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Looks up the <code>address</code> in the MaxMind DB.
|
||
|
|
*
|
||
|
|
* @param string $ipAddress
|
||
|
|
* the IP address to look up
|
||
|
|
*
|
||
|
|
* @throws \BadMethodCallException if this method is called on a closed database
|
||
|
|
* @throws \InvalidArgumentException if something other than a single IP address is passed to the method
|
||
|
|
* @throws InvalidDatabaseException
|
||
|
|
* if the database is invalid or there is an error reading
|
||
|
|
* from it
|
||
|
|
*
|
||
|
|
* @return array the record for the IP address
|
||
|
|
*/
|
||
|
|
public function get($ipAddress)
|
||
|
|
{
|
||
|
|
if (func_num_args() !== 1) {
|
||
|
|
throw new \InvalidArgumentException(
|
||
|
|
'Method takes exactly one argument.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
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 \"$ipAddress\" is not a valid IP address."
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($this->metadata->ipVersion === 4 && strrpos($ipAddress, ':')) {
|
||
|
|
throw new \InvalidArgumentException(
|
||
|
|
"Error looking up $ipAddress. You attempted to look up an"
|
||
|
|
. ' IPv6 address in an IPv4-only database.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
$pointer = $this->findAddressInTree($ipAddress);
|
||
|
|
if ($pointer === 0) {
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
|
||
|
|
return $this->resolveDataPointer($pointer);
|
||
|
|
}
|
||
|
|
|
||
|
|
private function findAddressInTree($ipAddress)
|
||
|
|
{
|
||
|
|
// XXX - could simplify. Done as a byte array to ease porting
|
||
|
|
$rawAddress = array_merge(unpack('C*', inet_pton($ipAddress)));
|
||
|
|
|
||
|
|
$bitCount = count($rawAddress) * 8;
|
||
|
|
|
||
|
|
// The first node of the tree is always node 0, at the beginning of the
|
||
|
|
// value
|
||
|
|
$node = $this->startNode($bitCount);
|
||
|
|
|
||
|
|
for ($i = 0; $i < $bitCount; $i++) {
|
||
|
|
if ($node >= $this->metadata->nodeCount) {
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
$tempBit = 0xFF & $rawAddress[$i >> 3];
|
||
|
|
$bit = 1 & ($tempBit >> 7 - ($i % 8));
|
||
|
|
|
||
|
|
$node = $this->readNode($node, $bit);
|
||
|
|
}
|
||
|
|
if ($node === $this->metadata->nodeCount) {
|
||
|
|
// Record is empty
|
||
|
|
return 0;
|
||
|
|
} elseif ($node > $this->metadata->nodeCount) {
|
||
|
|
// Record is a data pointer
|
||
|
|
return $node;
|
||
|
|
}
|
||
|
|
throw new InvalidDatabaseException('Something bad happened');
|
||
|
|
}
|
||
|
|
|
||
|
|
private function startNode($length)
|
||
|
|
{
|
||
|
|
// 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 ($this->metadata->ipVersion === 6 && $length === 32) {
|
||
|
|
return $this->ipV4StartNode();
|
||
|
|
}
|
||
|
|
// The first node of the tree is always node 0, at the beginning of the
|
||
|
|
// value
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
private function ipV4StartNode()
|
||
|
|
{
|
||
|
|
// This is a defensive check. There is no reason to call this when you
|
||
|
|
// have an IPv4 tree.
|
||
|
|
if ($this->metadata->ipVersion === 4) {
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($this->ipV4Start) {
|
||
|
|
return $this->ipV4Start;
|
||
|
|
}
|
||
|
|
$node = 0;
|
||
|
|
|
||
|
|
for ($i = 0; $i < 96 && $node < $this->metadata->nodeCount; $i++) {
|
||
|
|
$node = $this->readNode($node, 0);
|
||
|
|
}
|
||
|
|
$this->ipV4Start = $node;
|
||
|
|
|
||
|
|
return $node;
|
||
|
|
}
|
||
|
|
|
||
|
|
private function readNode($nodeNumber, $index)
|
||
|
|
{
|
||
|
|
$baseOffset = $nodeNumber * $this->metadata->nodeByteSize;
|
||
|
|
|
||
|
|
// XXX - probably could condense this.
|
||
|
|
switch ($this->metadata->recordSize) {
|
||
|
|
case 24:
|
||
|
|
$bytes = Util::read($this->fileHandle, $baseOffset + $index * 3, 3);
|
||
|
|
list(, $node) = unpack('N', "\x00" . $bytes);
|
||
|
|
|
||
|
|
return $node;
|
||
|
|
case 28:
|
||
|
|
$middleByte = Util::read($this->fileHandle, $baseOffset + 3, 1);
|
||
|
|
list(, $middle) = unpack('C', $middleByte);
|
||
|
|
if ($index === 0) {
|
||
|
|
$middle = (0xF0 & $middle) >> 4;
|
||
|
|
} else {
|
||
|
|
$middle = 0x0F & $middle;
|
||
|
|
}
|
||
|
|
$bytes = Util::read($this->fileHandle, $baseOffset + $index * 4, 3);
|
||
|
|
list(, $node) = unpack('N', chr($middle) . $bytes);
|
||
|
|
|
||
|
|
return $node;
|
||
|
|
case 32:
|
||
|
|
$bytes = Util::read($this->fileHandle, $baseOffset + $index * 4, 4);
|
||
|
|
list(, $node) = unpack('N', $bytes);
|
||
|
|
|
||
|
|
return $node;
|
||
|
|
default:
|
||
|
|
throw new InvalidDatabaseException(
|
||
|
|
'Unknown record size: '
|
||
|
|
. $this->metadata->recordSize
|
||
|
|
);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private function resolveDataPointer($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);
|
||
|
|
|
||
|
|
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)
|
||
|
|
{
|
||
|
|
$handle = $this->fileHandle;
|
||
|
|
$fstat = fstat($handle);
|
||
|
|
$fileSize = $fstat['size'];
|
||
|
|
$marker = self::$METADATA_START_MARKER;
|
||
|
|
$markerLength = self::$METADATA_START_MARKER_LENGTH;
|
||
|
|
$metadataMaxLengthExcludingMarker
|
||
|
|
= min(self::$METADATA_MAX_SIZE, $fileSize) - $markerLength;
|
||
|
|
|
||
|
|
for ($i = 0; $i <= $metadataMaxLengthExcludingMarker; $i++) {
|
||
|
|
for ($j = 0; $j < $markerLength; $j++) {
|
||
|
|
fseek($handle, $fileSize - $i - $j - 1);
|
||
|
|
$matchBit = fgetc($handle);
|
||
|
|
if ($matchBit !== $marker[$markerLength - $j - 1]) {
|
||
|
|
continue 2;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return $fileSize - $i;
|
||
|
|
}
|
||
|
|
throw new InvalidDatabaseException(
|
||
|
|
"Error opening database file ($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()
|
||
|
|
{
|
||
|
|
if (func_num_args()) {
|
||
|
|
throw new \InvalidArgumentException(
|
||
|
|
'Method takes no arguments.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
// 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 $this->metadata;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Closes the MaxMind DB and returns resources to the system.
|
||
|
|
*
|
||
|
|
* @throws \Exception
|
||
|
|
* if an I/O error occurs
|
||
|
|
*/
|
||
|
|
public function close()
|
||
|
|
{
|
||
|
|
if (!is_resource($this->fileHandle)) {
|
||
|
|
throw new \BadMethodCallException(
|
||
|
|
'Attempt to close a closed MaxMind DB.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
fclose($this->fileHandle);
|
||
|
|
}
|
||
|
|
}
|