<?php
/**
 * RouterOS API client implementation.
 *
 * @author    Denis Basta
 * @copyright 2008-2013 Denis Basta
 * @license   http://www.gnu.org/copyleft/lesser.html  LGPL License 2.1
 * @version   1.6
 */

class RouterosAPI
{
    public $debug     = false; // Show debug information
    public $connected = false; // Connection status
    public $port      = 8728;  // RouterOS API port
    public $timeout   = 3;     // Connection timeout
    public $attempts  = 5;     // Connection attempts
    public $delay     = 3;     // Delay between connection attempts

    private $socket;           // Socket resource
    private $error_no;         // Error number
    private $error_str;        // Error string

    /**
     * Connect to RouterOS
     *
     * @param string $ip       Hostname (IP or domain) of the RouterOS server
     * @param string $login    The RouterOS username
     * @param string $password The RouterOS password
     *
     * @return boolean Connection status
     */
    public function connect($ip, $login, $password)
    {
        for ($ATTEMPT = 1; $ATTEMPT <= $this->attempts; $ATTEMPT++) {
            $this->connected = false;
            $this->debug('Connection attempt #' . $ATTEMPT . ' to ' . $ip . ':' . $this->port . '...');
            $this->socket = @fsockopen($ip, $this->port, $this->error_no, $this->error_str, $this->timeout);
            if ($this->socket) {
                socket_set_timeout($this->socket, $this->timeout);
                $this->write('/login');
                $RESPONSE = $this->read(false);
                if (isset($RESPONSE[0]) && $RESPONSE[0] == '!done') {
                    if (preg_match_all('/[^=]+/i', $RESPONSE[1], $MATCHES)) {
                        if ($MATCHES[0][0] == 'ret' && strlen($MATCHES[0][1]) == 32) {
                            $this->write('/login', false);
                            $this->write('=name=' . $login, false);
                            $this->write('=response=00' . md5(chr(0) . $password . pack('H*', $MATCHES[0][1])));
                            $RESPONSE = $this->read(false);
                            if (isset($RESPONSE[0]) && $RESPONSE[0] == '!done') {
                                $this->connected = true;
                                break;
                            }
                        }
                    }
                }
                fclose($this->socket);
            }
            sleep($this->delay);
        }

        if ($this->connected) {
            $this->debug('Connected successfully to ' . $ip . ':' . $this->port);
        } else {
            $this->debug('Error connecting to ' . $ip . ':' . $this->port);
        }
        return $this->connected;
    }

    /**
     * Disconnect from RouterOS
     */
    public function disconnect()
    {
        fclose($this->socket);
        $this->connected = false;
        $this->debug('Disconnected');
    }

    /**
     * Parse response from RouterOS
     *
     * @param array $response Response data
     *
     * @return array Parsed data
     */
    public function parseResponse($response)
    {
        if (is_array($response)) {
            $PARSED      = array();
            $CURRENT     = null;
            $singlevalue = null;
            foreach ($response as $x) {
                if (in_array($x, array('!fatal', '!re', '!trap'))) {
                    if ($x == '!re') {
                        $CURRENT =& $PARSED[];
                    } else {
                        $CURRENT =& $PARSED[$x][];
                    }
                } elseif ($x != '!done') {
                    if (preg_match_all('/[^=]+/i', $x, $MATCHES)) {
                        if ($MATCHES[0][0] == 'ret') {
                            $singlevalue = $MATCHES[0][1];
                        }
                        $CURRENT[$MATCHES[0][0]] = (isset($MATCHES[0][1]) ? $MATCHES[0][1] : '');
                    }
                }
            }

            if (empty($PARSED) && !is_null($singlevalue)) {
                $PARSED = $singlevalue;
            }

            return $PARSED;
        } else {
            return array();
        }
    }

    /**
     * Read data from RouterOS
     *
     * @param boolean $parse Parse the data?
     *
     * @return array Data array
     */
    public function read($parse = true)
    {
        $RESPONSE = array();
        $line     = '';
        while (true) {
            $BYTE   = fread($this->socket, 1);
            $line  .= $BYTE;
            if ($BYTE == "\0") {
                $RESPONSE[] = $line;
                if (substr($line, -5) == "!done\0") {
                    break;
                }
                $line = '';
            }
        }

        if ($parse) {
            return $this->parseResponse($RESPONSE);
        } else {
            return $RESPONSE;
        }
    }

    /**
     * Write (send) data to RouterOS
     *
     * @param string  $command   A string with the command to send
     * @param boolean $param2    If we are sending a command, or a parameter
     *
     * @return void
     */
    public function write($command, $param2 = true)
    {
        if ($command) {
            $data = explode("\n", $command);
            foreach ($data as $com) {
                $com = trim($com);
                fwrite($this->socket, $this->encodeLength(strlen($com)) . $com);
                $this->debug('<<< ' . $com);
            }

            if (gettype($param2) == 'integer') {
                fwrite($this->socket, $this->encodeLength(strlen('.tag=' . $param2)) . '.tag=' . $param2 . "\0");
                $this->debug('<<< .tag=' . $param2);
            } elseif (gettype($param2) == 'boolean') {
                fwrite($this->socket, ($param2 ? '' : "\0"));
            }
        }
    }

    /**
     * Encode length of the string
     *
     * @param integer $length Length of the string
     *
     * @return string Encoded length
     */
    private function encodeLength($length)
    {
        if ($length < 0x80) {
            return chr($length);
        }
        if ($length < 0x4000) {
            return chr(($length >> 8) | 0x80) . chr($length & 0xFF);
        }
        if ($length < 0x200000) {
            return chr(($length >> 16) | 0xC0) . chr(($length >> 8) & 0xFF) . chr($length & 0xFF);
        }
        if ($length < 0x10000000) {
            return chr(($length >> 24) | 0xE0) . chr(($length >> 16) & 0xFF) . chr(($length >> 8) & 0xFF) . chr($length & 0xFF);
        }
        return chr(0xF0) . chr(($length >> 24) & 0xFF) . chr(($length >> 16) & 0xFF) . chr(($length >> 8) & 0xFF) . chr($length & 0xFF);
    }

    /**
     * Print debug information
     *
     * @param string $text Debug text
     *
     * @return void
     */
    private function debug($text)
    {
        if ($this->debug) {
            echo $text . "\n";
        }
    }
}