Viewing file:  RR.php (17.33 KB) -rw-rw-rw-
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
/**
* DNS Library for handling lookups and updates.
*
* PHP Version 5
*
* Copyright (c) 2010, Mike Pultz <mike@mikepultz.com>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of Mike Pultz nor the names of his contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRIC
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* @category Networking
* @package Net_DNS2
* @author Mike Pultz <mike@mikepultz.com>
* @copyright 2010 Mike Pultz <mike@mikepultz.com>
* @license http://www.opensource.org/licenses/bsd-license.php BSD License
* @version SVN: $Id: RR.php 134 2011-12-04 00:49:18Z mike.pultz $
* @link http://pear.php.net/package/Net_DNS2
* @since File available since Release 0.6.0
*
*/
/**
* This is the base class for DNS Resource Records
*
* Each resource record type (defined in RR/*.php) extends this class for
* base functionality.
*
* This class handles parsing and constructing the common parts of the DNS
* resource records, while the RR specific functionality is handled in each
* child class.
*
* DNS resource record format - RFC1035 section 4.1.3
*
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
* | |
* / /
* / NAME /
* | |
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
* | TYPE |
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
* | CLASS |
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
* | TTL |
* | |
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
* | RDLENGTH |
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
* / RDATA /
* / /
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
*
* @category Networking
* @package Net_DNS2
* @author Mike Pultz <mike@mikepultz.com>
* @license http://www.opensource.org/licenses/bsd-license.php BSD License
* @link http://pear.php.net/package/Net_DNS2
*
*/
abstract class Net_DNS2_RR
{
/*
* The name of the resource record
*/
public $name;
/*
* The resource record type
*/
public $type;
/*
* The resouce record class
*/
public $class;
/*
* The time to live for this resource record
*/
public $ttl;
/*
* The length of the rdata field
*/
public $rdlength;
/*
* The resource record specific data as a packed binary string
*/
public $rdata;
/**
* abstract definition - method to return a RR as a string; not to
* be confused with the __toString() magic method.
*
* @return string
* @access protected
*
*/
abstract protected function rrToString();
/**
* abstract definition - parses a RR from a standard DNS config line
*
* @param array $rdata a string split line of values for the rdata
*
* @return boolean
* @access protected
*
*/
abstract protected function rrFromString(array $rdata);
/**
* abstract definition - sets a Net_DNS2_RR from a Net_DNS2_Packet object
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet to parse the RR from
*
* @return boolean
* @access protected
*
*/
abstract protected function rrSet(Net_DNS2_Packet &$packet);
/**
* abstract definition - returns a binary packet DNS RR object
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet use for
* compressed names
*
* @return mixed either returns a binary packed string or
* null on failure
* @access protected
*
*/
abstract protected function rrGet(Net_DNS2_Packet &$packet);
/**
* Constructor - builds a new Net_DNS2_RR object
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet or null to create
* an empty object
* @param array $rr an array with RR parse values or null to
* create an empty object
*
* @throws Net_DNS2_Exception
* @access public
*
*/
public function __construct(Net_DNS2_Packet &$packet = null, array $rr = null)
{
if ( (!is_null($packet)) && (!is_null($rr)) ) {
if ($this->set($packet, $rr) == false) {
throw new Net_DNS2_Exception(
'failed to generate resource record',
Net_DNS2_Lookups::E_RR_INVALID
);
}
} else {
$class = Net_DNS2_Lookups::$rr_types_class_to_id[get_called_class()];
if (isset($class)) {
$this->type = Net_DNS2_Lookups::$rr_types_by_id[$class];
}
$this->class = 'IN';
$this->ttl = 86400;
}
}
/**
* magic __toString() method to return the Net_DNS2_RR object object as a string
*
* @return string
* @access public
*
*/
public function __toString()
{
return $this->name . '. ' . $this->ttl . ' ' . $this->class .
' ' . $this->type . ' ' . $this->rrToString();
}
/**
* return a formatted string; if a string has spaces in it, then return
* it with double quotes around it, otherwise, return it as it was passed in.
*
* @param string $string the string to format
*
* @return string
* @access protected
*
*/
protected function formatString($string)
{
return '"' . str_replace('"', '\"', trim($string, '"')) . '"';
}
/**
* builds an array of strings from an array of chunks of text split by spaces
*
* @param array $chunks an array of chunks of text split by spaces
*
* @return array
* @access protected
*
*/
protected function buildString(array $chunks)
{
$data = array();
$c = 0;
$in = false;
foreach ($chunks as $r) {
if ( ($r[0] == '"')
&& ($r[strlen($r) - 1] == '"')
&& ($r[strlen($r) - 2] != '\\')
) {
$data[$c] = $r;
++$c;
$in = false;
} else if ($r[0] == '"') {
$data[$c] = $r;
$in = true;
} else if ( ($r[strlen($r) - 1] == '"')
&& ($r[strlen($r) - 2] != '\\')
) {
$data[$c] .= ' ' . $r;
++$c;
$in = false;
} else {
if ($in == true) {
$data[$c] .= ' ' . $r;
} else {
$data[$c++] = $r;
}
}
}
foreach ($data as $index => $string) {
$data[$index] = str_replace('\"', '"', trim($string, '"'));
}
return $data;
}
/**
* builds a new Net_DNS2_RR object
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet or null to create
* an empty object
* @param array $rr an array with RR parse values or null to
* create an empty object
*
* @return boolean
* @throws Net_DNS2_Exception
* @access public
*
*/
public function set(Net_DNS2_Packet &$packet, array $rr)
{
$this->name = $rr['name'];
$this->type = Net_DNS2_Lookups::$rr_types_by_id[$rr['type']];
$this->class = Net_DNS2_Lookups::$classes_by_id[$rr['class']];
$this->ttl = $rr['ttl'];
$this->rdlength = $rr['rdlength'];
$this->rdata = substr($packet->rdata, $packet->offset, $rr['rdlength']);
return $this->rrSet($packet);
}
/**
* returns a binary packed DNS RR object
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet used for
* compressing names
*
* @return string
* @throws Net_DNS2_Exception
* @access public
*
*/
public function get(Net_DNS2_Packet &$packet)
{
$data = '';
$rdata = '';
//
// pack the name
//
$data = $packet->compress($this->name, $packet->offset);
//
// pack the main values
//
$data .= pack(
'nnN',
Net_DNS2_Lookups::$rr_types_by_name[$this->type],
Net_DNS2_Lookups::$classes_by_name[$this->class],
$this->ttl
);
//
// increase the offset, and allow for the rdlength
//
$packet->offset += 10;
//
// get the RR specific details
//
if ($this->rdlength != -1) {
$rdata = $this->rrGet($packet);
}
//
// add the RR
//
$data .= pack('n', strlen($rdata)) . $rdata;
return $data;
}
/**
* parses a binary packet, and returns the appropriate Net_DNS2_RR object,
* based on the RR type of the binary content.
*
* @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet used for
* decompressing names
*
* @return mixed returns a new Net_DNS2_RR_* object for
* the given RR
* @throws Net_DNS2_Exception
* @access public
*
*/
public static function parse(Net_DNS2_Packet &$packet)
{
$object = array();
//
// expand the name
//
$object['name'] = $packet->expand($packet, $packet->offset);
if (is_null($object['name'])) {
throw new Net_DNS2_Exception(
'failed to parse resource record: failed to expand name.',
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
if ($packet->rdlength < ($packet->offset + 10)) {
throw new Net_DNS2_Exception(
'failed to parse resource record: packet too small.',
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
//
// unpack the RR details
//
$object['type'] = ord($packet->rdata[$packet->offset++]) << 8 |
ord($packet->rdata[$packet->offset++]);
$object['class'] = ord($packet->rdata[$packet->offset++]) << 8 |
ord($packet->rdata[$packet->offset++]);
$object['ttl'] = ord($packet->rdata[$packet->offset++]) << 24 |
ord($packet->rdata[$packet->offset++]) << 16 |
ord($packet->rdata[$packet->offset++]) << 8 |
ord($packet->rdata[$packet->offset++]);
$object['rdlength'] = ord($packet->rdata[$packet->offset++]) << 8 |
ord($packet->rdata[$packet->offset++]);
if ($packet->rdlength < ($packet->offset + $object['rdlength'])) {
return null;
}
//
// lookup the class to use
//
$o = null;
$class = Net_DNS2_Lookups::$rr_types_id_to_class[$object['type']];
if (isset($class)) {
$o = new $class($packet, $object);
if ($o) {
$packet->offset += $object['rdlength'];
}
} else {
throw new Net_DNS2_Exception(
'un-implemented resource record type: ' . $object['type'],
Net_DNS2_Lookups::E_RR_INVALID
);
}
return $o;
}
/**
* cleans up some RR data
*
* @param string $data the text string to clean
*
* @return string returns the cleaned string
*
* @access public
*
*/
public function cleanString($data)
{
return strtolower(rtrim($data, '.'));
}
/**
* parses a standard RR format lines, as defined by rfc1035 (kinda)
*
* In our implementation, the domain *must* be specified- format must be
*
* <name> [<ttl>] [<class>] <type> <rdata>
* or
* <name> [<class>] [<ttl>] <type> <rdata>
*
* name, title, class and type are parsed by this function, rdata is passed
* to the RR specific classes for parsing.
*
* @param string $line a standard DNS config line
*
* @return mixed returns a new Net_DNS2_RR_* object for the given RR
* @throws Net_DNS2_Exception
* @access public
*
*/
public static function fromString($line)
{
if (strlen($line) == 0) {
throw new Net_DNS2_Exception(
'empty config line provided.',
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
$name = '';
$type = '';
$class = 'IN';
$ttl = 86400;
//
// split the line by spaces
//
$values = preg_split('/[\s]+/', $line);
if (count($values) < 3) {
throw new Net_DNS2_Exception(
'failed to parse config: minimum of name, type and rdata required.',
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
//
// assume the first value is the name
//
$name = trim(strtolower(array_shift($values)), '.');
//
// The next value is either a TTL, Class or Type
//
foreach ($values as $value) {
switch($value) {
case is_numeric($value):
$ttl = array_shift($values);
break;
//
// PHP SUCKS!
//
case ($value === 0):
$ttl = array_shift($values);
break;
case isset(Net_DNS2_Lookups::$classes_by_name[strtoupper($value)]):
$class = strtoupper(array_shift($values));
break;
case isset(Net_DNS2_Lookups::$rr_types_by_name[strtoupper($value)]):
$type = strtoupper(array_shift($values));
break 2;
break;
default:
throw new Net_DNS2_Exception(
'invalid config line provided: unknown file: ' . $value,
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
}
//
// lookup the class to use
//
$o = null;
$class_name = Net_DNS2_Lookups::$rr_types_id_to_class[
Net_DNS2_Lookups::$rr_types_by_name[$type]
];
if (isset($class_name)) {
$o = new $class_name;
if (!is_null($o)) {
//
// set the parsed values
//
$o->name = $name;
$o->class = $class;
$o->ttl = $ttl;
//
// parse the rdata
//
if ($o->rrFromString($values) === false) {
throw new Net_DNS2_Exception(
'failed to parse rdata for config: ' . $line,
Net_DNS2_Lookups::E_PARSE_ERROR
);
}
} else {
throw new Net_DNS2_Exception(
'failed to create new RR record for type: ' . $type,
Net_DNS2_Lookups::E_RR_INVALID
);
}
} else {
throw new Net_DNS2_Exception(
'un-implemented resource record type: '. $type,
Net_DNS2_Lookups::E_RR_INVALID
);
}
return $o;
}
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* c-hanging-comment-ender-p: nil
* End:
*/
?>
|