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   1  <?php
   2  /*
   3   * This file is part of the PHPASN1 library.
   4   *
   5   * Copyright © Friedrich Große <[email protected]>
   6   *
   7   * For the full copyright and license information, please view the LICENSE
   8   * file that was distributed with this source code.
   9   */
  10  
  11  namespace FG\ASN1\Universal;
  12  
  13  use Exception;
  14  use FG\ASN1\Base128;
  15  use FG\ASN1\OID;
  16  use FG\ASN1\ASNObject;
  17  use FG\ASN1\Parsable;
  18  use FG\ASN1\Identifier;
  19  use FG\ASN1\Exception\ParserException;
  20  
  21  class ObjectIdentifier extends ASNObject implements Parsable
  22  {
  23      protected $subIdentifiers;
  24      protected $value;
  25  
  26      public function __construct($value)
  27      {
  28          $this->subIdentifiers = explode('.', $value);
  29          $nrOfSubIdentifiers = count($this->subIdentifiers);
  30  
  31          for ($i = 0; $i < $nrOfSubIdentifiers; $i++) {
  32              if (is_numeric($this->subIdentifiers[$i])) {
  33                  // enforce the integer type
  34                  $this->subIdentifiers[$i] = intval($this->subIdentifiers[$i]);
  35              } else {
  36                  throw new Exception("[{$value}] is no valid object identifier (sub identifier ".($i + 1).' is not numeric)!');
  37              }
  38          }
  39  
  40          // Merge the first to arcs of the OID registration tree (per ASN definition!)
  41          if ($nrOfSubIdentifiers >= 2) {
  42              $this->subIdentifiers[1] = ($this->subIdentifiers[0] * 40) + $this->subIdentifiers[1];
  43              unset($this->subIdentifiers[0]);
  44          }
  45  
  46          $this->value = $value;
  47      }
  48  
  49      public function getContent()
  50      {
  51          return $this->value;
  52      }
  53  
  54      public function getType()
  55      {
  56          return Identifier::OBJECT_IDENTIFIER;
  57      }
  58  
  59      protected function calculateContentLength()
  60      {
  61          $length = 0;
  62          foreach ($this->subIdentifiers as $subIdentifier) {
  63              do {
  64                  $subIdentifier = $subIdentifier >> 7;
  65                  $length++;
  66              } while ($subIdentifier > 0);
  67          }
  68  
  69          return $length;
  70      }
  71  
  72      protected function getEncodedValue()
  73      {
  74          $encodedValue = '';
  75          foreach ($this->subIdentifiers as $subIdentifier) {
  76              $encodedValue .= Base128::encode($subIdentifier);
  77          }
  78  
  79          return $encodedValue;
  80      }
  81  
  82      public function __toString()
  83      {
  84          return OID::getName($this->value);
  85      }
  86  
  87      public static function fromBinary(&$binaryData, &$offsetIndex = 0)
  88      {
  89          self::parseIdentifier($binaryData[$offsetIndex], Identifier::OBJECT_IDENTIFIER, $offsetIndex++);
  90          $contentLength = self::parseContentLength($binaryData, $offsetIndex, 1);
  91  
  92          $firstOctet = ord($binaryData[$offsetIndex++]);
  93          $oidString = floor($firstOctet / 40).'.'.($firstOctet % 40);
  94          $oidString .= '.'.self::parseOid($binaryData, $offsetIndex, $contentLength - 1);
  95  
  96          $parsedObject = new self($oidString);
  97          $parsedObject->setContentLength($contentLength);
  98  
  99          return $parsedObject;
 100      }
 101  
 102      /**
 103       * Parses an object identifier except for the first octet, which is parsed
 104       * differently. This way relative object identifiers can also be parsed
 105       * using this.
 106       *
 107       * @param $binaryData
 108       * @param $offsetIndex
 109       * @param $octetsToRead
 110       *
 111       * @throws ParserException
 112       *
 113       * @return string
 114       */
 115      protected static function parseOid(&$binaryData, &$offsetIndex, $octetsToRead)
 116      {
 117          $oid = '';
 118  
 119          while ($octetsToRead > 0) {
 120              $octets = '';
 121  
 122              do {
 123                  if (0 === $octetsToRead) {
 124                      throw new ParserException('Malformed ASN.1 Object Identifier', $offsetIndex - 1);
 125                  }
 126  
 127                  $octetsToRead--;
 128                  $octet = $binaryData[$offsetIndex++];
 129                  $octets .= $octet;
 130              } while (ord($octet) & 0x80);
 131  
 132              $oid .= sprintf('%d.', Base128::decode($octets));
 133          }
 134  
 135          // Remove trailing '.'
 136          return substr($oid, 0, -1) ?: '';
 137      }
 138  }