<?php
/*
* This file is part of the PHPASN1 library.
*
* Copyright © Friedrich Große <friedrich.grosse@gmail.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace FG\ASN1\Universal;
use Exception;
use FG\ASN1\Base128;
use FG\ASN1\OID;
use FG\ASN1\ASNObject;
use FG\ASN1\Parsable;
use FG\ASN1\Identifier;
use FG\ASN1\Exception\ParserException;
class ObjectIdentifier extends ASNObject implements Parsable
{
protected $subIdentifiers;
protected $value;
public function __construct($value)
{
$this->subIdentifiers = explode('.', $value);
$nrOfSubIdentifiers = count($this->subIdentifiers);
for ($i = 0; $i < $nrOfSubIdentifiers; $i++) {
if (is_numeric($this->subIdentifiers[$i])) {
// enforce the integer type
$this->subIdentifiers[$i] = intval($this->subIdentifiers[$i]);
} else {
throw new Exception("[{$value}] is no valid object identifier (sub identifier ".($i + 1).' is not numeric)!');
}
}
// Merge the first to arcs of the OID registration tree (per ASN definition!)
if ($nrOfSubIdentifiers >= 2) {
$this->subIdentifiers[1] = ($this->subIdentifiers[0] * 40) + $this->subIdentifiers[1];
unset($this->subIdentifiers[0]);
}
$this->value = $value;
}
public function getContent()
{
return $this->value;
}
public function getType()
{
return Identifier::OBJECT_IDENTIFIER;
}
protected function calculateContentLength()
{
$length = 0;
foreach ($this->subIdentifiers as $subIdentifier) {
do {
$subIdentifier = $subIdentifier >> 7;
$length++;
} while ($subIdentifier > 0);
}
return $length;
}
protected function getEncodedValue()
{
$encodedValue = '';
foreach ($this->subIdentifiers as $subIdentifier) {
$encodedValue .= Base128::encode($subIdentifier);
}
return $encodedValue;
}
public function __toString()
{
return OID::getName($this->value);
}
public static function fromBinary(&$binaryData, &$offsetIndex = 0)
{
self::parseIdentifier($binaryData[$offsetIndex], Identifier::OBJECT_IDENTIFIER, $offsetIndex++);
$contentLength = self::parseContentLength($binaryData, $offsetIndex, 1);
$firstOctet = ord($binaryData[$offsetIndex++]);
$oidString = floor($firstOctet / 40).'.'.($firstOctet % 40);
$oidString .= '.'.self::parseOid($binaryData, $offsetIndex, $contentLength - 1);
$parsedObject = new self($oidString);
$parsedObject->setContentLength($contentLength);
return $parsedObject;
}
/**
* Parses an object identifier except for the first octet, which is parsed
* differently. This way relative object identifiers can also be parsed
* using this.
*
* @param $binaryData
* @param $offsetIndex
* @param $octetsToRead
*
* @throws ParserException
*
* @return string
*/
protected static function parseOid(&$binaryData, &$offsetIndex, $octetsToRead)
{
$oid = '';
while ($octetsToRead > 0) {
$octets = '';
do {
if (0 === $octetsToRead) {
throw new ParserException('Malformed ASN.1 Object Identifier', $offsetIndex - 1);
}
$octetsToRead--;
$octet = $binaryData[$offsetIndex++];
$octets .= $octet;
} while (ord($octet) & 0x80);
$oid .= sprintf('%d.', Base128::decode($octets));
}
// Remove trailing '.'
return substr($oid, 0, -1) ?: '';
}
}