add geolocation functionality

1 files changed, 373 insertions, 0 deletions

diff --git a/vendor/maxmind-db/reader/src/MaxMind/Db/Reader.php b/vendor/maxmind-db/reader/src/MaxMind/Db/Reader.php
new file mode 100644
index 0000000..4dfaef4
--- /dev/null
+++ b/vendor/maxmind-db/reader/src/MaxMind/Db/Reader.php
@@ -0,0 +1,373 @@
+<?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
+{
+    /**
+     * @var int
+     */
+    private static $DATA_SECTION_SEPARATOR_SIZE = 16;
+    /**
+     * @var string
+     */
+    private static $METADATA_START_MARKER = "\xAB\xCD\xEFMaxMind.com";
+    /**
+     * @var int
+     */
+    private static $METADATA_START_MARKER_LENGTH = 14;
+    /**
+     * @var int
+     */
+    private static $METADATA_MAX_SIZE = 131072; // 128 * 1024 = 128KiB
+
+    /**
+     * @var Decoder
+     */
+    private $decoder;
+    /**
+     * @var resource
+     */
+    private $fileHandle;
+    /**
+     * @var int
+     */
+    private $fileSize;
+    /**
+     * @var int
+     */
+    private $ipV4Start;
+    /**
+     * @var Metadata
+     */
+    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 InvalidDatabaseException
+     *                                  if the database is invalid or there is an error reading
+     *                                  from it
+     */
+    public function __construct(string $database)
+    {
+        if (\func_num_args() !== 1) {
+            throw new ArgumentCountError(
+                sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
+            );
+        }
+
+        $fileHandle = @fopen($database, 'rb');
+        if ($fileHandle === false) {
+            throw new InvalidArgumentException(
+                "The file \"$database\" does not exist or is not readable."
+            );
+        }
+        $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, $start);
+        [$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(string $ipAddress)
+    {
+        if (\func_num_args() !== 1) {
+            throw new ArgumentCountError(
+                sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
+            );
+        }
+        [$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(string $ipAddress): array
+    {
+        if (\func_num_args() !== 1) {
+            throw new ArgumentCountError(
+                sprintf('%s() expects exactly 1 parameter, %d given', __METHOD__, \func_num_args())
+            );
+        }
+
+        if (!\is_resource($this->fileHandle)) {
+            throw new BadMethodCallException(
+                'Attempt to read from a closed MaxMind DB.'
+            );
+        }
+
+        [$pointer, $prefixLen] = $this->findAddressInTree($ipAddress);
+        if ($pointer === 0) {
+            return [null, $prefixLen];
+        }
+
+        return [$this->resolveDataPointer($pointer), $prefixLen];
+    }
+
+    private function findAddressInTree(string $ipAddress): array
+    {
+        $packedAddr = @inet_pton($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, $i];
+        }
+        if ($node > $nodeCount) {
+            // Record is a data pointer
+            return [$node, $i];
+        }
+
+        throw new InvalidDatabaseException(
+            'Invalid or corrupt database. Maximum search depth reached without finding a leaf node'
+        );
+    }
+
+    private function ipV4StartNode(): int
+    {
+        // If we have an IPv4 database, the start node is the first node
+        if ($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(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);
+                [, $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]);
+                }
+                [, $node] = unpack('N', \chr($middle) . substr($bytes, $index, 3));
+
+                return $node;
+
+            case 32:
+                $bytes = Util::read($this->fileHandle, $baseOffset + $index * 4, 4);
+                [, $node] = unpack('N', $bytes);
+
+                return $node;
+
+            default:
+                throw new InvalidDatabaseException(
+                    'Unknown record size: '
+                    . $this->metadata->recordSize
+                );
+        }
+    }
+
+    /**
+     * @return mixed
+     */
+    private function resolveDataPointer(int $pointer)
+    {
+        $resolved = $pointer - $this->metadata->nodeCount
+            + $this->metadata->searchTreeSize;
+        if ($resolved >= $this->fileSize) {
+            throw new InvalidDatabaseException(
+                "The MaxMind DB file's search tree is corrupt"
+            );
+        }
+
+        [$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(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(): Metadata
+    {
+        if (\func_num_args()) {
+            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 clone $this->metadata;
+    }
+
+    /**
+     * Closes the MaxMind DB and returns resources to the system.
+     *
+     * @throws Exception
+     *                   if an I/O error occurs
+     */
+    public function close(): void
+    {
+        if (\func_num_args()) {
+            throw new ArgumentCountError(
+                sprintf('%s() expects exactly 0 parameters, %d given', __METHOD__, \func_num_args())
+            );
+        }
+
+        if (!\is_resource($this->fileHandle)) {
+            throw new BadMethodCallException(
+                'Attempt to close a closed MaxMind DB.'
+            );
+        }
+        fclose($this->fileHandle);
+    }
+}