sop / asn1

lib/ASN1/Type/Primitive/Integer.php

Indentation +148 added lines, -148 removed lines

@@ -17,161 +17,161 @@
  */
 class Integer extends Element
 {
-    use UniversalClass;
-    use PrimitiveType;
+	use UniversalClass;
+	use PrimitiveType;
 
-    /**
-     * The number.
-     *
-     * @var BigInt
-     */
-    private $_number;
+	/**
+	 * The number.
+	 *
+	 * @var BigInt
+	 */
+	private $_number;
 
-    /**
-     * Constructor.
-     *
-     * @param int|string $number Base 10 integer
-     */
-    public function __construct($number)
-    {
-        $this->_typeTag = self::TYPE_INTEGER;
-        if (!self::_validateNumber($number)) {
-            $var = is_scalar($number) ? strval($number) : gettype($number);
-            throw new \InvalidArgumentException("'{$var}' is not a valid number.");
-        }
-        $this->_number = new BigInt($number);
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @param int|string $number Base 10 integer
+	 */
+	public function __construct($number)
+	{
+		$this->_typeTag = self::TYPE_INTEGER;
+		if (!self::_validateNumber($number)) {
+			$var = is_scalar($number) ? strval($number) : gettype($number);
+			throw new \InvalidArgumentException("'{$var}' is not a valid number.");
+		}
+		$this->_number = new BigInt($number);
+	}
 
-    /**
-     * Get the number as a base 10.
-     *
-     * @return string Integer as a string
-     */
-    public function number(): string
-    {
-        return $this->_number->base10();
-    }
+	/**
+	 * Get the number as a base 10.
+	 *
+	 * @return string Integer as a string
+	 */
+	public function number(): string
+	{
+		return $this->_number->base10();
+	}
 
-    /**
-     * Get the number as an integer type.
-     *
-     * @return int
-     */
-    public function intNumber(): int
-    {
-        return $this->_number->intVal();
-    }
+	/**
+	 * Get the number as an integer type.
+	 *
+	 * @return int
+	 */
+	public function intNumber(): int
+	{
+		return $this->_number->intVal();
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function _encodedContentDER(): string
-    {
-        $num = $this->_number->gmpObj();
-        switch (gmp_sign($num)) {
-            // positive
-            case 1:
-                return self::_encodePositiveInteger($num);
-            // negative
-            case -1:
-                return self::_encodeNegativeInteger($num);
-        }
-        // zero
-        return "\0";
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function _encodedContentDER(): string
+	{
+		$num = $this->_number->gmpObj();
+		switch (gmp_sign($num)) {
+			// positive
+			case 1:
+				return self::_encodePositiveInteger($num);
+			// negative
+			case -1:
+				return self::_encodeNegativeInteger($num);
+		}
+		// zero
+		return "\0";
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected static function _decodeFromDER(Identifier $identifier,
-        string $data, int &$offset): ElementBase
-    {
-        $idx = $offset;
-        $length = Length::expectFromDER($data, $idx)->intLength();
-        $bytes = substr($data, $idx, $length);
-        $idx += $length;
-        $neg = ord($bytes[0]) & 0x80;
-        // negative, apply inversion of two's complement
-        if ($neg) {
-            $len = strlen($bytes);
-            for ($i = 0; $i < $len; ++$i) {
-                $bytes[$i] = ~$bytes[$i];
-            }
-        }
-        $num = gmp_init(bin2hex($bytes), 16);
-        // negative, apply addition of two's complement
-        // and produce negative result
-        if ($neg) {
-            $num = gmp_neg($num + 1);
-        }
-        $offset = $idx;
-        // late static binding since enumerated extends integer type
-        return new static(gmp_strval($num, 10));
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected static function _decodeFromDER(Identifier $identifier,
+		string $data, int &$offset): ElementBase
+	{
+		$idx = $offset;
+		$length = Length::expectFromDER($data, $idx)->intLength();
+		$bytes = substr($data, $idx, $length);
+		$idx += $length;
+		$neg = ord($bytes[0]) & 0x80;
+		// negative, apply inversion of two's complement
+		if ($neg) {
+			$len = strlen($bytes);
+			for ($i = 0; $i < $len; ++$i) {
+				$bytes[$i] = ~$bytes[$i];
+			}
+		}
+		$num = gmp_init(bin2hex($bytes), 16);
+		// negative, apply addition of two's complement
+		// and produce negative result
+		if ($neg) {
+			$num = gmp_neg($num + 1);
+		}
+		$offset = $idx;
+		// late static binding since enumerated extends integer type
+		return new static(gmp_strval($num, 10));
+	}
 
-    /**
-     * Encode positive integer to DER content.
-     *
-     * @param \GMP $num
-     *
-     * @return string
-     */
-    private static function _encodePositiveInteger(\GMP $num): string
-    {
-        $bin = gmp_export($num, 1, GMP_MSW_FIRST | GMP_BIG_ENDIAN);
-        // if first bit is 1, prepend full zero byte
-        // to represent positive two's complement
-        if (ord($bin[0]) & 0x80) {
-            $bin = chr(0x00) . $bin;
-        }
-        return $bin;
-    }
+	/**
+	 * Encode positive integer to DER content.
+	 *
+	 * @param \GMP $num
+	 *
+	 * @return string
+	 */
+	private static function _encodePositiveInteger(\GMP $num): string
+	{
+		$bin = gmp_export($num, 1, GMP_MSW_FIRST | GMP_BIG_ENDIAN);
+		// if first bit is 1, prepend full zero byte
+		// to represent positive two's complement
+		if (ord($bin[0]) & 0x80) {
+			$bin = chr(0x00) . $bin;
+		}
+		return $bin;
+	}
 
-    /**
-     * Encode negative integer to DER content.
-     *
-     * @param \GMP $num
-     *
-     * @return string
-     */
-    private static function _encodeNegativeInteger(\GMP $num): string
-    {
-        $num = gmp_abs($num);
-        // compute number of bytes required
-        $width = 1;
-        if ($num > 128) {
-            $tmp = $num;
-            do {
-                ++$width;
-                $tmp >>= 8;
-            } while ($tmp > 128);
-        }
-        // compute two's complement 2^n - x
-        $num = gmp_pow('2', 8 * $width) - $num;
-        $bin = gmp_export($num, 1, GMP_MSW_FIRST | GMP_BIG_ENDIAN);
-        // if first bit is 0, prepend full inverted byte
-        // to represent negative two's complement
-        if (!(ord($bin[0]) & 0x80)) {
-            $bin = chr(0xff) . $bin;
-        }
-        return $bin;
-    }
+	/**
+	 * Encode negative integer to DER content.
+	 *
+	 * @param \GMP $num
+	 *
+	 * @return string
+	 */
+	private static function _encodeNegativeInteger(\GMP $num): string
+	{
+		$num = gmp_abs($num);
+		// compute number of bytes required
+		$width = 1;
+		if ($num > 128) {
+			$tmp = $num;
+			do {
+				++$width;
+				$tmp >>= 8;
+			} while ($tmp > 128);
+		}
+		// compute two's complement 2^n - x
+		$num = gmp_pow('2', 8 * $width) - $num;
+		$bin = gmp_export($num, 1, GMP_MSW_FIRST | GMP_BIG_ENDIAN);
+		// if first bit is 0, prepend full inverted byte
+		// to represent negative two's complement
+		if (!(ord($bin[0]) & 0x80)) {
+			$bin = chr(0xff) . $bin;
+		}
+		return $bin;
+	}
 
-    /**
-     * Test that number is valid for this context.
-     *
-     * @param mixed $num
-     *
-     * @return bool
-     */
-    private static function _validateNumber($num): bool
-    {
-        if (is_int($num)) {
-            return true;
-        }
-        if (is_string($num) && preg_match('/-?\d+/', $num)) {
-            return true;
-        }
-        return false;
-    }
+	/**
+	 * Test that number is valid for this context.
+	 *
+	 * @param mixed $num
+	 *
+	 * @return bool
+	 */
+	private static function _validateNumber($num): bool
+	{
+		if (is_int($num)) {
+			return true;
+		}
+		if (is_string($num) && preg_match('/-?\d+/', $num)) {
+			return true;
+		}
+		return false;
+	}
 }

lib/ASN1/Type/Primitive/ObjectIdentifier.php

Indentation +185 added lines, -185 removed lines

@@ -17,199 +17,199 @@
  */
 class ObjectIdentifier extends Element
 {
-    use UniversalClass;
-    use PrimitiveType;
+	use UniversalClass;
+	use PrimitiveType;
 
-    /**
-     * Object identifier in dotted format.
-     *
-     * @var string
-     */
-    protected $_oid;
+	/**
+	 * Object identifier in dotted format.
+	 *
+	 * @var string
+	 */
+	protected $_oid;
 
-    /**
-     * Object identifier split to sub ID's.
-     *
-     * @var \GMP[]
-     */
-    protected $_subids;
+	/**
+	 * Object identifier split to sub ID's.
+	 *
+	 * @var \GMP[]
+	 */
+	protected $_subids;
 
-    /**
-     * Constructor.
-     *
-     * @param string $oid OID in dotted format
-     */
-    public function __construct(string $oid)
-    {
-        $this->_oid = $oid;
-        $this->_subids = self::_explodeDottedOID($oid);
-        // if OID is non-empty
-        if (count($this->_subids) > 0) {
-            // check that at least two nodes are set
-            if (count($this->_subids) < 2) {
-                throw new \UnexpectedValueException(
-                    'OID must have at least two nodes.');
-            }
-            // check that root arc is in 0..2 range
-            if ($this->_subids[0] > 2) {
-                throw new \UnexpectedValueException(
-                    'Root arc must be in range of 0..2.');
-            }
-            // if root arc is 0 or 1, second node must be in 0..39 range
-            if ($this->_subids[0] < 2 && $this->_subids[1] >= 40) {
-                throw new \UnexpectedValueException(
-                    'Second node must be in 0..39 range for root arcs 0 and 1.');
-            }
-        }
-        $this->_typeTag = self::TYPE_OBJECT_IDENTIFIER;
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @param string $oid OID in dotted format
+	 */
+	public function __construct(string $oid)
+	{
+		$this->_oid = $oid;
+		$this->_subids = self::_explodeDottedOID($oid);
+		// if OID is non-empty
+		if (count($this->_subids) > 0) {
+			// check that at least two nodes are set
+			if (count($this->_subids) < 2) {
+				throw new \UnexpectedValueException(
+					'OID must have at least two nodes.');
+			}
+			// check that root arc is in 0..2 range
+			if ($this->_subids[0] > 2) {
+				throw new \UnexpectedValueException(
+					'Root arc must be in range of 0..2.');
+			}
+			// if root arc is 0 or 1, second node must be in 0..39 range
+			if ($this->_subids[0] < 2 && $this->_subids[1] >= 40) {
+				throw new \UnexpectedValueException(
+					'Second node must be in 0..39 range for root arcs 0 and 1.');
+			}
+		}
+		$this->_typeTag = self::TYPE_OBJECT_IDENTIFIER;
+	}
 
-    /**
-     * Get OID in dotted format.
-     *
-     * @return string
-     */
-    public function oid(): string
-    {
-        return $this->_oid;
-    }
+	/**
+	 * Get OID in dotted format.
+	 *
+	 * @return string
+	 */
+	public function oid(): string
+	{
+		return $this->_oid;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function _encodedContentDER(): string
-    {
-        $subids = $this->_subids;
-        // encode first two subids to one according to spec section 8.19.4
-        if (count($subids) >= 2) {
-            $num = ($subids[0] * 40) + $subids[1];
-            array_splice($subids, 0, 2, [$num]);
-        }
-        return self::_encodeSubIDs(...$subids);
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function _encodedContentDER(): string
+	{
+		$subids = $this->_subids;
+		// encode first two subids to one according to spec section 8.19.4
+		if (count($subids) >= 2) {
+			$num = ($subids[0] * 40) + $subids[1];
+			array_splice($subids, 0, 2, [$num]);
+		}
+		return self::_encodeSubIDs(...$subids);
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected static function _decodeFromDER(Identifier $identifier,
-        string $data, int &$offset): ElementBase
-    {
-        $idx = $offset;
-        $len = Length::expectFromDER($data, $idx)->intLength();
-        $subids = self::_decodeSubIDs(substr($data, $idx, $len));
-        $idx += $len;
-        // decode first subidentifier according to spec section 8.19.4
-        if (isset($subids[0])) {
-            if ($subids[0] < 80) {
-                [$x, $y] = gmp_div_qr($subids[0], '40');
-            } else {
-                $x = gmp_init(2, 10);
-                $y = $subids[0] - 80;
-            }
-            array_splice($subids, 0, 1, [$x, $y]);
-        }
-        $offset = $idx;
-        return new self(self::_implodeSubIDs(...$subids));
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected static function _decodeFromDER(Identifier $identifier,
+		string $data, int &$offset): ElementBase
+	{
+		$idx = $offset;
+		$len = Length::expectFromDER($data, $idx)->intLength();
+		$subids = self::_decodeSubIDs(substr($data, $idx, $len));
+		$idx += $len;
+		// decode first subidentifier according to spec section 8.19.4
+		if (isset($subids[0])) {
+			if ($subids[0] < 80) {
+				[$x, $y] = gmp_div_qr($subids[0], '40');
+			} else {
+				$x = gmp_init(2, 10);
+				$y = $subids[0] - 80;
+			}
+			array_splice($subids, 0, 1, [$x, $y]);
+		}
+		$offset = $idx;
+		return new self(self::_implodeSubIDs(...$subids));
+	}
 
-    /**
-     * Explode dotted OID to an array of sub ID's.
-     *
-     * @param string $oid OID in dotted format
-     *
-     * @return \GMP[] Array of GMP numbers
-     */
-    protected static function _explodeDottedOID(string $oid): array
-    {
-        $subids = [];
-        if (strlen($oid)) {
-            foreach (explode('.', $oid) as $subid) {
-                $n = @gmp_init($subid, 10);
-                if (false === $n) {
-                    throw new \UnexpectedValueException(
-                        "'{$subid}' is not a number.");
-                }
-                $subids[] = $n;
-            }
-        }
-        return $subids;
-    }
+	/**
+	 * Explode dotted OID to an array of sub ID's.
+	 *
+	 * @param string $oid OID in dotted format
+	 *
+	 * @return \GMP[] Array of GMP numbers
+	 */
+	protected static function _explodeDottedOID(string $oid): array
+	{
+		$subids = [];
+		if (strlen($oid)) {
+			foreach (explode('.', $oid) as $subid) {
+				$n = @gmp_init($subid, 10);
+				if (false === $n) {
+					throw new \UnexpectedValueException(
+						"'{$subid}' is not a number.");
+				}
+				$subids[] = $n;
+			}
+		}
+		return $subids;
+	}
 
-    /**
-     * Implode an array of sub IDs to dotted OID format.
-     *
-     * @param \GMP ...$subids
-     *
-     * @return string
-     */
-    protected static function _implodeSubIDs(\GMP ...$subids): string
-    {
-        return implode('.',
-            array_map(function ($num) {
-                return gmp_strval($num, 10);
-            }, $subids));
-    }
+	/**
+	 * Implode an array of sub IDs to dotted OID format.
+	 *
+	 * @param \GMP ...$subids
+	 *
+	 * @return string
+	 */
+	protected static function _implodeSubIDs(\GMP ...$subids): string
+	{
+		return implode('.',
+			array_map(function ($num) {
+				return gmp_strval($num, 10);
+			}, $subids));
+	}
 
-    /**
-     * Encode sub ID's to DER.
-     *
-     * @param \GMP ...$subids
-     *
-     * @return string
-     */
-    protected static function _encodeSubIDs(\GMP ...$subids): string
-    {
-        $data = '';
-        foreach ($subids as $subid) {
-            // if number fits to one base 128 byte
-            if ($subid < 128) {
-                $data .= chr(intval($subid));
-            } else { // encode to multiple bytes
-                $bytes = [];
-                do {
-                    array_unshift($bytes, 0x7f & gmp_intval($subid));
-                    $subid >>= 7;
-                } while ($subid > 0);
-                // all bytes except last must have bit 8 set to one
-                foreach (array_splice($bytes, 0, -1) as $byte) {
-                    $data .= chr(0x80 | $byte);
-                }
-                $data .= chr(reset($bytes));
-            }
-        }
-        return $data;
-    }
+	/**
+	 * Encode sub ID's to DER.
+	 *
+	 * @param \GMP ...$subids
+	 *
+	 * @return string
+	 */
+	protected static function _encodeSubIDs(\GMP ...$subids): string
+	{
+		$data = '';
+		foreach ($subids as $subid) {
+			// if number fits to one base 128 byte
+			if ($subid < 128) {
+				$data .= chr(intval($subid));
+			} else { // encode to multiple bytes
+				$bytes = [];
+				do {
+					array_unshift($bytes, 0x7f & gmp_intval($subid));
+					$subid >>= 7;
+				} while ($subid > 0);
+				// all bytes except last must have bit 8 set to one
+				foreach (array_splice($bytes, 0, -1) as $byte) {
+					$data .= chr(0x80 | $byte);
+				}
+				$data .= chr(reset($bytes));
+			}
+		}
+		return $data;
+	}
 
-    /**
-     * Decode sub ID's from DER data.
-     *
-     * @param string $data
-     *
-     * @throws DecodeException
-     *
-     * @return \GMP[] Array of GMP numbers
-     */
-    protected static function _decodeSubIDs(string $data): array
-    {
-        $subids = [];
-        $idx = 0;
-        $end = strlen($data);
-        while ($idx < $end) {
-            $num = gmp_init('0', 10);
-            while (true) {
-                if ($idx >= $end) {
-                    throw new DecodeException('Unexpected end of data.');
-                }
-                $byte = ord($data[$idx++]);
-                $num |= $byte & 0x7f;
-                // bit 8 of the last octet is zero
-                if (!($byte & 0x80)) {
-                    break;
-                }
-                $num <<= 7;
-            }
-            $subids[] = $num;
-        }
-        return $subids;
-    }
+	/**
+	 * Decode sub ID's from DER data.
+	 *
+	 * @param string $data
+	 *
+	 * @throws DecodeException
+	 *
+	 * @return \GMP[] Array of GMP numbers
+	 */
+	protected static function _decodeSubIDs(string $data): array
+	{
+		$subids = [];
+		$idx = 0;
+		$end = strlen($data);
+		while ($idx < $end) {
+			$num = gmp_init('0', 10);
+			while (true) {
+				if ($idx >= $end) {
+					throw new DecodeException('Unexpected end of data.');
+				}
+				$byte = ord($data[$idx++]);
+				$num |= $byte & 0x7f;
+				// bit 8 of the last octet is zero
+				if (!($byte & 0x80)) {
+					break;
+				}
+				$num <<= 7;
+			}
+			$subids[] = $num;
+		}
+		return $subids;
+	}
 }

lib/ASN1/Element.php

Indentation +478 added lines, -478 removed lines

@@ -25,482 +25,482 @@
  */
 abstract class Element implements ElementBase
 {
-    // Universal type tags
-    const TYPE_EOC = 0x00;
-    const TYPE_BOOLEAN = 0x01;
-    const TYPE_INTEGER = 0x02;
-    const TYPE_BIT_STRING = 0x03;
-    const TYPE_OCTET_STRING = 0x04;
-    const TYPE_NULL = 0x05;
-    const TYPE_OBJECT_IDENTIFIER = 0x06;
-    const TYPE_OBJECT_DESCRIPTOR = 0x07;
-    const TYPE_EXTERNAL = 0x08;
-    const TYPE_REAL = 0x09;
-    const TYPE_ENUMERATED = 0x0a;
-    const TYPE_EMBEDDED_PDV = 0x0b;
-    const TYPE_UTF8_STRING = 0x0c;
-    const TYPE_RELATIVE_OID = 0x0d;
-    const TYPE_SEQUENCE = 0x10;
-    const TYPE_SET = 0x11;
-    const TYPE_NUMERIC_STRING = 0x12;
-    const TYPE_PRINTABLE_STRING = 0x13;
-    const TYPE_T61_STRING = 0x14;
-    const TYPE_VIDEOTEX_STRING = 0x15;
-    const TYPE_IA5_STRING = 0x16;
-    const TYPE_UTC_TIME = 0x17;
-    const TYPE_GENERALIZED_TIME = 0x18;
-    const TYPE_GRAPHIC_STRING = 0x19;
-    const TYPE_VISIBLE_STRING = 0x1a;
-    const TYPE_GENERAL_STRING = 0x1b;
-    const TYPE_UNIVERSAL_STRING = 0x1c;
-    const TYPE_CHARACTER_STRING = 0x1d;
-    const TYPE_BMP_STRING = 0x1e;
-
-    /**
-     * Mapping from universal type tag to implementation class name.
-     *
-     * @internal
-     *
-     * @var array
-     */
-    const MAP_TAG_TO_CLASS = [
-        self::TYPE_EOC => Primitive\EOC::class,
-        self::TYPE_BOOLEAN => Primitive\Boolean::class,
-        self::TYPE_INTEGER => Primitive\Integer::class,
-        self::TYPE_BIT_STRING => Primitive\BitString::class,
-        self::TYPE_OCTET_STRING => Primitive\OctetString::class,
-        self::TYPE_NULL => Primitive\NullType::class,
-        self::TYPE_OBJECT_IDENTIFIER => Primitive\ObjectIdentifier::class,
-        self::TYPE_OBJECT_DESCRIPTOR => Primitive\ObjectDescriptor::class,
-        self::TYPE_REAL => Primitive\Real::class,
-        self::TYPE_ENUMERATED => Primitive\Enumerated::class,
-        self::TYPE_UTF8_STRING => Primitive\UTF8String::class,
-        self::TYPE_RELATIVE_OID => Primitive\RelativeOID::class,
-        self::TYPE_SEQUENCE => Constructed\Sequence::class,
-        self::TYPE_SET => Constructed\Set::class,
-        self::TYPE_NUMERIC_STRING => Primitive\NumericString::class,
-        self::TYPE_PRINTABLE_STRING => Primitive\PrintableString::class,
-        self::TYPE_T61_STRING => Primitive\T61String::class,
-        self::TYPE_VIDEOTEX_STRING => Primitive\VideotexString::class,
-        self::TYPE_IA5_STRING => Primitive\IA5String::class,
-        self::TYPE_UTC_TIME => Primitive\UTCTime::class,
-        self::TYPE_GENERALIZED_TIME => Primitive\GeneralizedTime::class,
-        self::TYPE_GRAPHIC_STRING => Primitive\GraphicString::class,
-        self::TYPE_VISIBLE_STRING => Primitive\VisibleString::class,
-        self::TYPE_GENERAL_STRING => Primitive\GeneralString::class,
-        self::TYPE_UNIVERSAL_STRING => Primitive\UniversalString::class,
-        self::TYPE_CHARACTER_STRING => Primitive\CharacterString::class,
-        self::TYPE_BMP_STRING => Primitive\BMPString::class,
-    ];
-
-    /**
-     * Pseudotype for all string types.
-     *
-     * May be used as an expectation parameter.
-     *
-     * @var int
-     */
-    const TYPE_STRING = -1;
-
-    /**
-     * Pseudotype for all time types.
-     *
-     * May be used as an expectation parameter.
-     *
-     * @var int
-     */
-    const TYPE_TIME = -2;
-
-    /**
-     * Pseudotype for constructed strings.
-     *
-     * May be used as an expectation parameter.
-     *
-     * @var int
-     */
-    const TYPE_CONSTRUCTED_STRING = -3;
-
-    /**
-     * Mapping from universal type tag to human readable name.
-     *
-     * @internal
-     *
-     * @var array
-     */
-    const MAP_TYPE_TO_NAME = [
-        self::TYPE_EOC => 'EOC',
-        self::TYPE_BOOLEAN => 'BOOLEAN',
-        self::TYPE_INTEGER => 'INTEGER',
-        self::TYPE_BIT_STRING => 'BIT STRING',
-        self::TYPE_OCTET_STRING => 'OCTET STRING',
-        self::TYPE_NULL => 'NULL',
-        self::TYPE_OBJECT_IDENTIFIER => 'OBJECT IDENTIFIER',
-        self::TYPE_OBJECT_DESCRIPTOR => 'ObjectDescriptor',
-        self::TYPE_EXTERNAL => 'EXTERNAL',
-        self::TYPE_REAL => 'REAL',
-        self::TYPE_ENUMERATED => 'ENUMERATED',
-        self::TYPE_EMBEDDED_PDV => 'EMBEDDED PDV',
-        self::TYPE_UTF8_STRING => 'UTF8String',
-        self::TYPE_RELATIVE_OID => 'RELATIVE-OID',
-        self::TYPE_SEQUENCE => 'SEQUENCE',
-        self::TYPE_SET => 'SET',
-        self::TYPE_NUMERIC_STRING => 'NumericString',
-        self::TYPE_PRINTABLE_STRING => 'PrintableString',
-        self::TYPE_T61_STRING => 'T61String',
-        self::TYPE_VIDEOTEX_STRING => 'VideotexString',
-        self::TYPE_IA5_STRING => 'IA5String',
-        self::TYPE_UTC_TIME => 'UTCTime',
-        self::TYPE_GENERALIZED_TIME => 'GeneralizedTime',
-        self::TYPE_GRAPHIC_STRING => 'GraphicString',
-        self::TYPE_VISIBLE_STRING => 'VisibleString',
-        self::TYPE_GENERAL_STRING => 'GeneralString',
-        self::TYPE_UNIVERSAL_STRING => 'UniversalString',
-        self::TYPE_CHARACTER_STRING => 'CHARACTER STRING',
-        self::TYPE_BMP_STRING => 'BMPString',
-        self::TYPE_STRING => 'Any String',
-        self::TYPE_TIME => 'Any Time',
-        self::TYPE_CONSTRUCTED_STRING => 'Constructed String',
-    ];
-
-    /**
-     * Element's type tag.
-     *
-     * @var int
-     */
-    protected $_typeTag;
-
-    /**
-     * Whether type shall be encoded with indefinite length.
-     *
-     * @var bool
-     */
-    protected $_indefiniteLength = false;
-
-    /**
-     * {@inheritdoc}
-     */
-    abstract public function typeClass(): int;
-
-    /**
-     * {@inheritdoc}
-     */
-    abstract public function isConstructed(): bool;
-
-    /**
-     * Decode element from DER data.
-     *
-     * @param string   $data   DER encoded data
-     * @param null|int $offset Reference to the variable that contains offset
-     *                         into the data where to start parsing.
-     *                         Variable is updated to the offset next to the
-     *                         parsed element. If null, start from offset 0.
-     *
-     * @throws DecodeException           If decoding fails
-     * @throws \UnexpectedValueException If called in the context of an expected
-     *                                   type, but decoding yields another type
-     *
-     * @return ElementBase
-     */
-    public static function fromDER(string $data, int &$offset = null): ElementBase
-    {
-        $idx = $offset ?? 0;
-        // decode identifier
-        $identifier = Identifier::fromDER($data, $idx);
-        // determine class that implements type specific decoding
-        $cls = self::_determineImplClass($identifier);
-        try {
-            // decode remaining element
-            $element = $cls::_decodeFromDER($identifier, $data, $idx);
-        } catch (\LogicException $e) {
-            // rethrow as a RuntimeException for unified exception handling
-            throw new DecodeException(
-                sprintf('Error while decoding %s.',
-                    self::tagToName($identifier->intTag())), 0, $e);
-        }
-        // if called in the context of a concrete class, check
-        // that decoded type matches the type of a calling class
-        $called_class = get_called_class();
-        if (self::class !== $called_class) {
-            if (!$element instanceof $called_class) {
-                throw new \UnexpectedValueException(
-                    sprintf('%s expected, got %s.', $called_class,
-                        get_class($element)));
-            }
-        }
-        // update offset for the caller
-        if (isset($offset)) {
-            $offset = $idx;
-        }
-        return $element;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function toDER(): string
-    {
-        $identifier = new Identifier($this->typeClass(),
-            $this->isConstructed() ? Identifier::CONSTRUCTED : Identifier::PRIMITIVE,
-            $this->_typeTag);
-        $content = $this->_encodedContentDER();
-        if ($this->_indefiniteLength) {
-            $length = new Length(0, true);
-            $eoc = new Primitive\EOC();
-            return $identifier->toDER() . $length->toDER() . $content . $eoc->toDER();
-        }
-        $length = new Length(strlen($content));
-        return $identifier->toDER() . $length->toDER() . $content;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function tag(): int
-    {
-        return $this->_typeTag;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function isType(int $tag): bool
-    {
-        // if element is context specific
-        if (Identifier::CLASS_CONTEXT_SPECIFIC === $this->typeClass()) {
-            return false;
-        }
-        // negative tags identify an abstract pseudotype
-        if ($tag < 0) {
-            return $this->_isPseudoType($tag);
-        }
-        return $this->_isConcreteType($tag);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function expectType(int $tag): ElementBase
-    {
-        if (!$this->isType($tag)) {
-            throw new \UnexpectedValueException(
-                sprintf('%s expected, got %s.', self::tagToName($tag),
-                    $this->_typeDescriptorString()));
-        }
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function isTagged(): bool
-    {
-        return $this instanceof TaggedType;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function expectTagged(?int $tag = null): TaggedType
-    {
-        if (!$this->isTagged()) {
-            throw new \UnexpectedValueException(
-                sprintf('Context specific element expected, got %s.',
-                    Identifier::classToName($this->typeClass())));
-        }
-        if (isset($tag) && $this->tag() !== $tag) {
-            throw new \UnexpectedValueException(
-                sprintf('Tag %d expected, got %d.', $tag, $this->tag()));
-        }
-        return $this;
-    }
-
-    /**
-     * Whether element has indefinite length.
-     *
-     * @return bool
-     */
-    public function hasIndefiniteLength(): bool
-    {
-        return $this->_indefiniteLength;
-    }
-
-    /**
-     * Get self with indefinite length encoding set.
-     *
-     * @param bool $indefinite True for indefinite length, false for definite length
-     *
-     * @return self
-     */
-    public function withIndefiniteLength(bool $indefinite = true): self
-    {
-        $obj = clone $this;
-        $obj->_indefiniteLength = $indefinite;
-        return $obj;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    final public function asElement(): Element
-    {
-        return $this;
-    }
-
-    /**
-     * Get element decorated with UnspecifiedType object.
-     *
-     * @return UnspecifiedType
-     */
-    public function asUnspecified(): UnspecifiedType
-    {
-        return new UnspecifiedType($this);
-    }
-
-    /**
-     * Get human readable name for an universal tag.
-     *
-     * @param int $tag
-     *
-     * @return string
-     */
-    public static function tagToName(int $tag): string
-    {
-        if (!array_key_exists($tag, self::MAP_TYPE_TO_NAME)) {
-            return "TAG {$tag}";
-        }
-        return self::MAP_TYPE_TO_NAME[$tag];
-    }
-
-    /**
-     * Get the content encoded in DER.
-     *
-     * Returns the DER encoded content without identifier and length header octets.
-     *
-     * @return string
-     */
-    abstract protected function _encodedContentDER(): string;
-
-    /**
-     * Decode type-specific element from DER.
-     *
-     * @param Identifier $identifier Pre-parsed identifier
-     * @param string     $data       DER data
-     * @param int        $offset     Offset in data to the next byte after identifier
-     *
-     * @throws DecodeException If decoding fails
-     *
-     * @return ElementBase
-     */
-    protected static function _decodeFromDER(Identifier $identifier,
-        string $data, int &$offset): ElementBase
-    {
-        throw new \BadMethodCallException(
-            __METHOD__ . ' must be implemented in derived class.');
-    }
-
-    /**
-     * Determine the class that implements the type.
-     *
-     * @param Identifier $identifier
-     *
-     * @return string Class name
-     */
-    protected static function _determineImplClass(Identifier $identifier): string
-    {
-        switch ($identifier->typeClass()) {
-            case Identifier::CLASS_UNIVERSAL:
-                $cls = self::_determineUniversalImplClass($identifier->intTag());
-                // constructed strings may be present in BER
-                if ($identifier->isConstructed() &&
-                    is_subclass_of($cls, PrimitiveString::class)) {
-                    $cls = ConstructedString::class;
-                }
-                return $cls;
-            case Identifier::CLASS_CONTEXT_SPECIFIC:
-                return ContextSpecificType::class;
-            case Identifier::CLASS_APPLICATION:
-                return ApplicationType::class;
-            case Identifier::CLASS_PRIVATE:
-                return PrivateType::class;
-        }
-        throw new \UnexpectedValueException(
-            sprintf('%s %d not implemented.',
-                Identifier::classToName($identifier->typeClass()),
-                $identifier->tag()));
-    }
-
-    /**
-     * Determine the class that implements an universal type of the given tag.
-     *
-     * @param int $tag
-     *
-     * @throws \UnexpectedValueException
-     *
-     * @return string Class name
-     */
-    protected static function _determineUniversalImplClass(int $tag): string
-    {
-        if (!array_key_exists($tag, self::MAP_TAG_TO_CLASS)) {
-            throw new \UnexpectedValueException(
-                "Universal tag {$tag} not implemented.");
-        }
-        return self::MAP_TAG_TO_CLASS[$tag];
-    }
-
-    /**
-     * Get textual description of the type for debugging purposes.
-     *
-     * @return string
-     */
-    protected function _typeDescriptorString(): string
-    {
-        if (Identifier::CLASS_UNIVERSAL === $this->typeClass()) {
-            return self::tagToName($this->_typeTag);
-        }
-        return sprintf('%s TAG %d', Identifier::classToName($this->typeClass()),
-            $this->_typeTag);
-    }
-
-    /**
-     * Check whether the element is a concrete type of a given tag.
-     *
-     * @param int $tag
-     *
-     * @return bool
-     */
-    private function _isConcreteType(int $tag): bool
-    {
-        // if tag doesn't match
-        if ($this->tag() !== $tag) {
-            return false;
-        }
-        // if type is universal check that instance is of a correct class
-        if (Identifier::CLASS_UNIVERSAL === $this->typeClass()) {
-            $cls = self::_determineUniversalImplClass($tag);
-            if (!$this instanceof $cls) {
-                return false;
-            }
-        }
-        return true;
-    }
-
-    /**
-     * Check whether the element is a pseudotype.
-     *
-     * @param int $tag
-     *
-     * @return bool
-     */
-    private function _isPseudoType(int $tag): bool
-    {
-        switch ($tag) {
-            case self::TYPE_STRING:
-                return $this instanceof StringType;
-            case self::TYPE_TIME:
-                return $this instanceof TimeType;
-            case self::TYPE_CONSTRUCTED_STRING:
-                return $this instanceof ConstructedString;
-        }
-        return false;
-    }
+	// Universal type tags
+	const TYPE_EOC = 0x00;
+	const TYPE_BOOLEAN = 0x01;
+	const TYPE_INTEGER = 0x02;
+	const TYPE_BIT_STRING = 0x03;
+	const TYPE_OCTET_STRING = 0x04;
+	const TYPE_NULL = 0x05;
+	const TYPE_OBJECT_IDENTIFIER = 0x06;
+	const TYPE_OBJECT_DESCRIPTOR = 0x07;
+	const TYPE_EXTERNAL = 0x08;
+	const TYPE_REAL = 0x09;
+	const TYPE_ENUMERATED = 0x0a;
+	const TYPE_EMBEDDED_PDV = 0x0b;
+	const TYPE_UTF8_STRING = 0x0c;
+	const TYPE_RELATIVE_OID = 0x0d;
+	const TYPE_SEQUENCE = 0x10;
+	const TYPE_SET = 0x11;
+	const TYPE_NUMERIC_STRING = 0x12;
+	const TYPE_PRINTABLE_STRING = 0x13;
+	const TYPE_T61_STRING = 0x14;
+	const TYPE_VIDEOTEX_STRING = 0x15;
+	const TYPE_IA5_STRING = 0x16;
+	const TYPE_UTC_TIME = 0x17;
+	const TYPE_GENERALIZED_TIME = 0x18;
+	const TYPE_GRAPHIC_STRING = 0x19;
+	const TYPE_VISIBLE_STRING = 0x1a;
+	const TYPE_GENERAL_STRING = 0x1b;
+	const TYPE_UNIVERSAL_STRING = 0x1c;
+	const TYPE_CHARACTER_STRING = 0x1d;
+	const TYPE_BMP_STRING = 0x1e;
+
+	/**
+	 * Mapping from universal type tag to implementation class name.
+	 *
+	 * @internal
+	 *
+	 * @var array
+	 */
+	const MAP_TAG_TO_CLASS = [
+		self::TYPE_EOC => Primitive\EOC::class,
+		self::TYPE_BOOLEAN => Primitive\Boolean::class,
+		self::TYPE_INTEGER => Primitive\Integer::class,
+		self::TYPE_BIT_STRING => Primitive\BitString::class,
+		self::TYPE_OCTET_STRING => Primitive\OctetString::class,
+		self::TYPE_NULL => Primitive\NullType::class,
+		self::TYPE_OBJECT_IDENTIFIER => Primitive\ObjectIdentifier::class,
+		self::TYPE_OBJECT_DESCRIPTOR => Primitive\ObjectDescriptor::class,
+		self::TYPE_REAL => Primitive\Real::class,
+		self::TYPE_ENUMERATED => Primitive\Enumerated::class,
+		self::TYPE_UTF8_STRING => Primitive\UTF8String::class,
+		self::TYPE_RELATIVE_OID => Primitive\RelativeOID::class,
+		self::TYPE_SEQUENCE => Constructed\Sequence::class,
+		self::TYPE_SET => Constructed\Set::class,
+		self::TYPE_NUMERIC_STRING => Primitive\NumericString::class,
+		self::TYPE_PRINTABLE_STRING => Primitive\PrintableString::class,
+		self::TYPE_T61_STRING => Primitive\T61String::class,
+		self::TYPE_VIDEOTEX_STRING => Primitive\VideotexString::class,
+		self::TYPE_IA5_STRING => Primitive\IA5String::class,
+		self::TYPE_UTC_TIME => Primitive\UTCTime::class,
+		self::TYPE_GENERALIZED_TIME => Primitive\GeneralizedTime::class,
+		self::TYPE_GRAPHIC_STRING => Primitive\GraphicString::class,
+		self::TYPE_VISIBLE_STRING => Primitive\VisibleString::class,
+		self::TYPE_GENERAL_STRING => Primitive\GeneralString::class,
+		self::TYPE_UNIVERSAL_STRING => Primitive\UniversalString::class,
+		self::TYPE_CHARACTER_STRING => Primitive\CharacterString::class,
+		self::TYPE_BMP_STRING => Primitive\BMPString::class,
+	];
+
+	/**
+	 * Pseudotype for all string types.
+	 *
+	 * May be used as an expectation parameter.
+	 *
+	 * @var int
+	 */
+	const TYPE_STRING = -1;
+
+	/**
+	 * Pseudotype for all time types.
+	 *
+	 * May be used as an expectation parameter.
+	 *
+	 * @var int
+	 */
+	const TYPE_TIME = -2;
+
+	/**
+	 * Pseudotype for constructed strings.
+	 *
+	 * May be used as an expectation parameter.
+	 *
+	 * @var int
+	 */
+	const TYPE_CONSTRUCTED_STRING = -3;
+
+	/**
+	 * Mapping from universal type tag to human readable name.
+	 *
+	 * @internal
+	 *
+	 * @var array
+	 */
+	const MAP_TYPE_TO_NAME = [
+		self::TYPE_EOC => 'EOC',
+		self::TYPE_BOOLEAN => 'BOOLEAN',
+		self::TYPE_INTEGER => 'INTEGER',
+		self::TYPE_BIT_STRING => 'BIT STRING',
+		self::TYPE_OCTET_STRING => 'OCTET STRING',
+		self::TYPE_NULL => 'NULL',
+		self::TYPE_OBJECT_IDENTIFIER => 'OBJECT IDENTIFIER',
+		self::TYPE_OBJECT_DESCRIPTOR => 'ObjectDescriptor',
+		self::TYPE_EXTERNAL => 'EXTERNAL',
+		self::TYPE_REAL => 'REAL',
+		self::TYPE_ENUMERATED => 'ENUMERATED',
+		self::TYPE_EMBEDDED_PDV => 'EMBEDDED PDV',
+		self::TYPE_UTF8_STRING => 'UTF8String',
+		self::TYPE_RELATIVE_OID => 'RELATIVE-OID',
+		self::TYPE_SEQUENCE => 'SEQUENCE',
+		self::TYPE_SET => 'SET',
+		self::TYPE_NUMERIC_STRING => 'NumericString',
+		self::TYPE_PRINTABLE_STRING => 'PrintableString',
+		self::TYPE_T61_STRING => 'T61String',
+		self::TYPE_VIDEOTEX_STRING => 'VideotexString',
+		self::TYPE_IA5_STRING => 'IA5String',
+		self::TYPE_UTC_TIME => 'UTCTime',
+		self::TYPE_GENERALIZED_TIME => 'GeneralizedTime',
+		self::TYPE_GRAPHIC_STRING => 'GraphicString',
+		self::TYPE_VISIBLE_STRING => 'VisibleString',
+		self::TYPE_GENERAL_STRING => 'GeneralString',
+		self::TYPE_UNIVERSAL_STRING => 'UniversalString',
+		self::TYPE_CHARACTER_STRING => 'CHARACTER STRING',
+		self::TYPE_BMP_STRING => 'BMPString',
+		self::TYPE_STRING => 'Any String',
+		self::TYPE_TIME => 'Any Time',
+		self::TYPE_CONSTRUCTED_STRING => 'Constructed String',
+	];
+
+	/**
+	 * Element's type tag.
+	 *
+	 * @var int
+	 */
+	protected $_typeTag;
+
+	/**
+	 * Whether type shall be encoded with indefinite length.
+	 *
+	 * @var bool
+	 */
+	protected $_indefiniteLength = false;
+
+	/**
+	 * {@inheritdoc}
+	 */
+	abstract public function typeClass(): int;
+
+	/**
+	 * {@inheritdoc}
+	 */
+	abstract public function isConstructed(): bool;
+
+	/**
+	 * Decode element from DER data.
+	 *
+	 * @param string   $data   DER encoded data
+	 * @param null|int $offset Reference to the variable that contains offset
+	 *                         into the data where to start parsing.
+	 *                         Variable is updated to the offset next to the
+	 *                         parsed element. If null, start from offset 0.
+	 *
+	 * @throws DecodeException           If decoding fails
+	 * @throws \UnexpectedValueException If called in the context of an expected
+	 *                                   type, but decoding yields another type
+	 *
+	 * @return ElementBase
+	 */
+	public static function fromDER(string $data, int &$offset = null): ElementBase
+	{
+		$idx = $offset ?? 0;
+		// decode identifier
+		$identifier = Identifier::fromDER($data, $idx);
+		// determine class that implements type specific decoding
+		$cls = self::_determineImplClass($identifier);
+		try {
+			// decode remaining element
+			$element = $cls::_decodeFromDER($identifier, $data, $idx);
+		} catch (\LogicException $e) {
+			// rethrow as a RuntimeException for unified exception handling
+			throw new DecodeException(
+				sprintf('Error while decoding %s.',
+					self::tagToName($identifier->intTag())), 0, $e);
+		}
+		// if called in the context of a concrete class, check
+		// that decoded type matches the type of a calling class
+		$called_class = get_called_class();
+		if (self::class !== $called_class) {
+			if (!$element instanceof $called_class) {
+				throw new \UnexpectedValueException(
+					sprintf('%s expected, got %s.', $called_class,
+						get_class($element)));
+			}
+		}
+		// update offset for the caller
+		if (isset($offset)) {
+			$offset = $idx;
+		}
+		return $element;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function toDER(): string
+	{
+		$identifier = new Identifier($this->typeClass(),
+			$this->isConstructed() ? Identifier::CONSTRUCTED : Identifier::PRIMITIVE,
+			$this->_typeTag);
+		$content = $this->_encodedContentDER();
+		if ($this->_indefiniteLength) {
+			$length = new Length(0, true);
+			$eoc = new Primitive\EOC();
+			return $identifier->toDER() . $length->toDER() . $content . $eoc->toDER();
+		}
+		$length = new Length(strlen($content));
+		return $identifier->toDER() . $length->toDER() . $content;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function tag(): int
+	{
+		return $this->_typeTag;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isType(int $tag): bool
+	{
+		// if element is context specific
+		if (Identifier::CLASS_CONTEXT_SPECIFIC === $this->typeClass()) {
+			return false;
+		}
+		// negative tags identify an abstract pseudotype
+		if ($tag < 0) {
+			return $this->_isPseudoType($tag);
+		}
+		return $this->_isConcreteType($tag);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function expectType(int $tag): ElementBase
+	{
+		if (!$this->isType($tag)) {
+			throw new \UnexpectedValueException(
+				sprintf('%s expected, got %s.', self::tagToName($tag),
+					$this->_typeDescriptorString()));
+		}
+		return $this;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isTagged(): bool
+	{
+		return $this instanceof TaggedType;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function expectTagged(?int $tag = null): TaggedType
+	{
+		if (!$this->isTagged()) {
+			throw new \UnexpectedValueException(
+				sprintf('Context specific element expected, got %s.',
+					Identifier::classToName($this->typeClass())));
+		}
+		if (isset($tag) && $this->tag() !== $tag) {
+			throw new \UnexpectedValueException(
+				sprintf('Tag %d expected, got %d.', $tag, $this->tag()));
+		}
+		return $this;
+	}
+
+	/**
+	 * Whether element has indefinite length.
+	 *
+	 * @return bool
+	 */
+	public function hasIndefiniteLength(): bool
+	{
+		return $this->_indefiniteLength;
+	}
+
+	/**
+	 * Get self with indefinite length encoding set.
+	 *
+	 * @param bool $indefinite True for indefinite length, false for definite length
+	 *
+	 * @return self
+	 */
+	public function withIndefiniteLength(bool $indefinite = true): self
+	{
+		$obj = clone $this;
+		$obj->_indefiniteLength = $indefinite;
+		return $obj;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	final public function asElement(): Element
+	{
+		return $this;
+	}
+
+	/**
+	 * Get element decorated with UnspecifiedType object.
+	 *
+	 * @return UnspecifiedType
+	 */
+	public function asUnspecified(): UnspecifiedType
+	{
+		return new UnspecifiedType($this);
+	}
+
+	/**
+	 * Get human readable name for an universal tag.
+	 *
+	 * @param int $tag
+	 *
+	 * @return string
+	 */
+	public static function tagToName(int $tag): string
+	{
+		if (!array_key_exists($tag, self::MAP_TYPE_TO_NAME)) {
+			return "TAG {$tag}";
+		}
+		return self::MAP_TYPE_TO_NAME[$tag];
+	}
+
+	/**
+	 * Get the content encoded in DER.
+	 *
+	 * Returns the DER encoded content without identifier and length header octets.
+	 *
+	 * @return string
+	 */
+	abstract protected function _encodedContentDER(): string;
+
+	/**
+	 * Decode type-specific element from DER.
+	 *
+	 * @param Identifier $identifier Pre-parsed identifier
+	 * @param string     $data       DER data
+	 * @param int        $offset     Offset in data to the next byte after identifier
+	 *
+	 * @throws DecodeException If decoding fails
+	 *
+	 * @return ElementBase
+	 */
+	protected static function _decodeFromDER(Identifier $identifier,
+		string $data, int &$offset): ElementBase
+	{
+		throw new \BadMethodCallException(
+			__METHOD__ . ' must be implemented in derived class.');
+	}
+
+	/**
+	 * Determine the class that implements the type.
+	 *
+	 * @param Identifier $identifier
+	 *
+	 * @return string Class name
+	 */
+	protected static function _determineImplClass(Identifier $identifier): string
+	{
+		switch ($identifier->typeClass()) {
+			case Identifier::CLASS_UNIVERSAL:
+				$cls = self::_determineUniversalImplClass($identifier->intTag());
+				// constructed strings may be present in BER
+				if ($identifier->isConstructed() &&
+					is_subclass_of($cls, PrimitiveString::class)) {
+					$cls = ConstructedString::class;
+				}
+				return $cls;
+			case Identifier::CLASS_CONTEXT_SPECIFIC:
+				return ContextSpecificType::class;
+			case Identifier::CLASS_APPLICATION:
+				return ApplicationType::class;
+			case Identifier::CLASS_PRIVATE:
+				return PrivateType::class;
+		}
+		throw new \UnexpectedValueException(
+			sprintf('%s %d not implemented.',
+				Identifier::classToName($identifier->typeClass()),
+				$identifier->tag()));
+	}
+
+	/**
+	 * Determine the class that implements an universal type of the given tag.
+	 *
+	 * @param int $tag
+	 *
+	 * @throws \UnexpectedValueException
+	 *
+	 * @return string Class name
+	 */
+	protected static function _determineUniversalImplClass(int $tag): string
+	{
+		if (!array_key_exists($tag, self::MAP_TAG_TO_CLASS)) {
+			throw new \UnexpectedValueException(
+				"Universal tag {$tag} not implemented.");
+		}
+		return self::MAP_TAG_TO_CLASS[$tag];
+	}
+
+	/**
+	 * Get textual description of the type for debugging purposes.
+	 *
+	 * @return string
+	 */
+	protected function _typeDescriptorString(): string
+	{
+		if (Identifier::CLASS_UNIVERSAL === $this->typeClass()) {
+			return self::tagToName($this->_typeTag);
+		}
+		return sprintf('%s TAG %d', Identifier::classToName($this->typeClass()),
+			$this->_typeTag);
+	}
+
+	/**
+	 * Check whether the element is a concrete type of a given tag.
+	 *
+	 * @param int $tag
+	 *
+	 * @return bool
+	 */
+	private function _isConcreteType(int $tag): bool
+	{
+		// if tag doesn't match
+		if ($this->tag() !== $tag) {
+			return false;
+		}
+		// if type is universal check that instance is of a correct class
+		if (Identifier::CLASS_UNIVERSAL === $this->typeClass()) {
+			$cls = self::_determineUniversalImplClass($tag);
+			if (!$this instanceof $cls) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+	/**
+	 * Check whether the element is a pseudotype.
+	 *
+	 * @param int $tag
+	 *
+	 * @return bool
+	 */
+	private function _isPseudoType(int $tag): bool
+	{
+		switch ($tag) {
+			case self::TYPE_STRING:
+				return $this instanceof StringType;
+			case self::TYPE_TIME:
+				return $this instanceof TimeType;
+			case self::TYPE_CONSTRUCTED_STRING:
+				return $this instanceof ConstructedString;
+		}
+		return false;
+	}
 }

lib/ASN1/Type/Constructed/Set.php

Indentation +50 added lines, -50 removed lines

@@ -12,56 +12,56 @@
  */
 class Set extends Structure
 {
-    /**
-     * Constructor.
-     *
-     * @param Element ...$elements Any number of elements
-     */
-    public function __construct(Element ...$elements)
-    {
-        $this->_typeTag = self::TYPE_SET;
-        parent::__construct(...$elements);
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @param Element ...$elements Any number of elements
+	 */
+	public function __construct(Element ...$elements)
+	{
+		$this->_typeTag = self::TYPE_SET;
+		parent::__construct(...$elements);
+	}
 
-    /**
-     * Sort by canonical ascending order.
-     *
-     * Used for DER encoding of SET type.
-     *
-     * @return self
-     */
-    public function sortedSet(): self
-    {
-        $obj = clone $this;
-        usort($obj->_elements,
-            function (Element $a, Element $b) {
-                if ($a->typeClass() !== $b->typeClass()) {
-                    return $a->typeClass() < $b->typeClass() ? -1 : 1;
-                }
-                if ($a->tag() === $b->tag()) {
-                    return 0;
-                }
-                return $a->tag() < $b->tag() ? -1 : 1;
-            });
-        return $obj;
-    }
+	/**
+	 * Sort by canonical ascending order.
+	 *
+	 * Used for DER encoding of SET type.
+	 *
+	 * @return self
+	 */
+	public function sortedSet(): self
+	{
+		$obj = clone $this;
+		usort($obj->_elements,
+			function (Element $a, Element $b) {
+				if ($a->typeClass() !== $b->typeClass()) {
+					return $a->typeClass() < $b->typeClass() ? -1 : 1;
+				}
+				if ($a->tag() === $b->tag()) {
+					return 0;
+				}
+				return $a->tag() < $b->tag() ? -1 : 1;
+			});
+		return $obj;
+	}
 
-    /**
-     * Sort by encoding ascending order.
-     *
-     * Used for DER encoding of SET OF type.
-     *
-     * @return self
-     */
-    public function sortedSetOf(): self
-    {
-        $obj = clone $this;
-        usort($obj->_elements,
-            function (Element $a, Element $b) {
-                $a_der = $a->toDER();
-                $b_der = $b->toDER();
-                return strcmp($a_der, $b_der);
-            });
-        return $obj;
-    }
+	/**
+	 * Sort by encoding ascending order.
+	 *
+	 * Used for DER encoding of SET OF type.
+	 *
+	 * @return self
+	 */
+	public function sortedSetOf(): self
+	{
+		$obj = clone $this;
+		usort($obj->_elements,
+			function (Element $a, Element $b) {
+				$a_der = $a->toDER();
+				$b_der = $b->toDER();
+				return strcmp($a_der, $b_der);
+			});
+		return $obj;
+	}
 }

lib/ASN1/Type/Constructed/ConstructedString.php

Indentation +98 added lines, -98 removed lines

@@ -26,108 +26,108 @@
  */
 class ConstructedString extends Structure implements Stringable
 {
-    /**
-     * Constructor.
-     *
-     * @internal Use create() method instead
-     *
-     * @param Element ...$elements Any number of elements
-     */
-    protected function __construct(Element ...$elements)
-    {
-        parent::__construct(...$elements);
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @internal Use create() method instead
+	 *
+	 * @param Element ...$elements Any number of elements
+	 */
+	protected function __construct(Element ...$elements)
+	{
+		parent::__construct(...$elements);
+	}
 
-    /**
-     * {@inheritdoc}
-     *
-     * @return string
-     */
-    public function __toString(): string
-    {
-        return $this->string();
-    }
+	/**
+	 * {@inheritdoc}
+	 *
+	 * @return string
+	 */
+	public function __toString(): string
+	{
+		return $this->string();
+	}
 
-    /**
-     * Create from a list of string type elements.
-     *
-     * All strings must have the same type.
-     *
-     * @param StringType ...$elements
-     *
-     * @throws \LogicException
-     *
-     * @return self
-     */
-    public static function create(StringType ...$elements): self
-    {
-        if (!count($elements)) {
-            throw new \LogicException(
-                'No elements, unable to determine type tag.');
-        }
-        $tag = $elements[0]->tag();
-        foreach ($elements as $el) {
-            if ($el->tag() !== $tag) {
-                throw new \LogicException(
-                    'All elements in constructed string must have the same type.');
-            }
-        }
-        return self::createWithTag($tag, ...$elements);
-    }
+	/**
+	 * Create from a list of string type elements.
+	 *
+	 * All strings must have the same type.
+	 *
+	 * @param StringType ...$elements
+	 *
+	 * @throws \LogicException
+	 *
+	 * @return self
+	 */
+	public static function create(StringType ...$elements): self
+	{
+		if (!count($elements)) {
+			throw new \LogicException(
+				'No elements, unable to determine type tag.');
+		}
+		$tag = $elements[0]->tag();
+		foreach ($elements as $el) {
+			if ($el->tag() !== $tag) {
+				throw new \LogicException(
+					'All elements in constructed string must have the same type.');
+			}
+		}
+		return self::createWithTag($tag, ...$elements);
+	}
 
-    /**
-     * Create from strings with a given type tag.
-     *
-     * Does not perform any validation on types.
-     *
-     * @param int        $tag         Type tag for the constructed string element
-     * @param StringType ...$elements Any number of elements
-     *
-     * @return self
-     */
-    public static function createWithTag(int $tag, StringType ...$elements)
-    {
-        $el = new self(...$elements);
-        $el->_typeTag = $tag;
-        return $el;
-    }
+	/**
+	 * Create from strings with a given type tag.
+	 *
+	 * Does not perform any validation on types.
+	 *
+	 * @param int        $tag         Type tag for the constructed string element
+	 * @param StringType ...$elements Any number of elements
+	 *
+	 * @return self
+	 */
+	public static function createWithTag(int $tag, StringType ...$elements)
+	{
+		$el = new self(...$elements);
+		$el->_typeTag = $tag;
+		return $el;
+	}
 
-    /**
-     * Get a list of strings in this structure.
-     *
-     * @return string[]
-     */
-    public function strings(): array
-    {
-        return array_map(function (StringType $el) {
-            return $el->string();
-        }, $this->_elements);
-    }
+	/**
+	 * Get a list of strings in this structure.
+	 *
+	 * @return string[]
+	 */
+	public function strings(): array
+	{
+		return array_map(function (StringType $el) {
+			return $el->string();
+		}, $this->_elements);
+	}
 
-    /**
-     * Get the contained strings concatenated together.
-     *
-     * NOTE: It's unclear how bit strings with unused bits should be concatentated.
-     *
-     * @return string
-     */
-    public function string(): string
-    {
-        return implode('', $this->strings());
-    }
+	/**
+	 * Get the contained strings concatenated together.
+	 *
+	 * NOTE: It's unclear how bit strings with unused bits should be concatentated.
+	 *
+	 * @return string
+	 */
+	public function string(): string
+	{
+		return implode('', $this->strings());
+	}
 
-    /**
-     * {@inheritdoc}
-     *
-     * @return self
-     */
-    protected static function _decodeFromDER(Identifier $identifier,
-        string $data, int &$offset): ElementBase
-    {
-        /** @var ConstructedString $type */
-        $type = forward_static_call_array([parent::class, __FUNCTION__],
-            [$identifier, $data, &$offset]);
-        $type->_typeTag = $identifier->intTag();
-        return $type;
-    }
+	/**
+	 * {@inheritdoc}
+	 *
+	 * @return self
+	 */
+	protected static function _decodeFromDER(Identifier $identifier,
+		string $data, int &$offset): ElementBase
+	{
+		/** @var ConstructedString $type */
+		$type = forward_static_call_array([parent::class, __FUNCTION__],
+			[$identifier, $data, &$offset]);
+		$type->_typeTag = $identifier->intTag();
+		return $type;
+	}
 }

lib/ASN1/Type/Structure.php

Indentation +375 added lines, -375 removed lines

@@ -15,402 +15,402 @@
  */
 abstract class Structure extends Element implements \Countable, \IteratorAggregate
 {
-    use UniversalClass;
+	use UniversalClass;
 
-    /**
-     * Array of elements in the structure.
-     *
-     * @var Element[]
-     */
-    protected $_elements;
+	/**
+	 * Array of elements in the structure.
+	 *
+	 * @var Element[]
+	 */
+	protected $_elements;
 
-    /**
-     * Lookup table for the tagged elements.
-     *
-     * @var null|TaggedType[]
-     */
-    private $_taggedMap;
+	/**
+	 * Lookup table for the tagged elements.
+	 *
+	 * @var null|TaggedType[]
+	 */
+	private $_taggedMap;
 
-    /**
-     * Cache variable of elements wrapped into UnspecifiedType objects.
-     *
-     * @var null|UnspecifiedType[]
-     */
-    private $_unspecifiedTypes;
+	/**
+	 * Cache variable of elements wrapped into UnspecifiedType objects.
+	 *
+	 * @var null|UnspecifiedType[]
+	 */
+	private $_unspecifiedTypes;
 
-    /**
-     * Constructor.
-     *
-     * @param ElementBase ...$elements Any number of elements
-     */
-    public function __construct(ElementBase ...$elements)
-    {
-        $this->_elements = array_map(
-            function (ElementBase $el) {
-                return $el->asElement();
-            }, $elements);
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @param ElementBase ...$elements Any number of elements
+	 */
+	public function __construct(ElementBase ...$elements)
+	{
+		$this->_elements = array_map(
+			function (ElementBase $el) {
+				return $el->asElement();
+			}, $elements);
+	}
 
-    /**
-     * Clone magic method.
-     */
-    public function __clone()
-    {
-        // clear cache-variables
-        $this->_taggedMap = null;
-        $this->_unspecifiedTypes = null;
-    }
+	/**
+	 * Clone magic method.
+	 */
+	public function __clone()
+	{
+		// clear cache-variables
+		$this->_taggedMap = null;
+		$this->_unspecifiedTypes = null;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function isConstructed(): bool
-    {
-        return true;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isConstructed(): bool
+	{
+		return true;
+	}
 
-    /**
-     * Explode DER structure to DER encoded components that it contains.
-     *
-     * @param string $data
-     *
-     * @throws DecodeException
-     *
-     * @return string[]
-     */
-    public static function explodeDER(string $data): array
-    {
-        $offset = 0;
-        $identifier = Identifier::fromDER($data, $offset);
-        if (!$identifier->isConstructed()) {
-            throw new DecodeException('Element is not constructed.');
-        }
-        $length = Length::expectFromDER($data, $offset);
-        if ($length->isIndefinite()) {
-            throw new DecodeException(
-                'Explode not implemented for indefinite length encoding.');
-        }
-        $end = $offset + $length->intLength();
-        $parts = [];
-        while ($offset < $end) {
-            // start of the element
-            $idx = $offset;
-            // skip identifier
-            Identifier::fromDER($data, $offset);
-            // decode element length
-            $length = Length::expectFromDER($data, $offset)->intLength();
-            // extract der encoding of the element
-            $parts[] = substr($data, $idx, $offset - $idx + $length);
-            // update offset over content
-            $offset += $length;
-        }
-        return $parts;
-    }
+	/**
+	 * Explode DER structure to DER encoded components that it contains.
+	 *
+	 * @param string $data
+	 *
+	 * @throws DecodeException
+	 *
+	 * @return string[]
+	 */
+	public static function explodeDER(string $data): array
+	{
+		$offset = 0;
+		$identifier = Identifier::fromDER($data, $offset);
+		if (!$identifier->isConstructed()) {
+			throw new DecodeException('Element is not constructed.');
+		}
+		$length = Length::expectFromDER($data, $offset);
+		if ($length->isIndefinite()) {
+			throw new DecodeException(
+				'Explode not implemented for indefinite length encoding.');
+		}
+		$end = $offset + $length->intLength();
+		$parts = [];
+		while ($offset < $end) {
+			// start of the element
+			$idx = $offset;
+			// skip identifier
+			Identifier::fromDER($data, $offset);
+			// decode element length
+			$length = Length::expectFromDER($data, $offset)->intLength();
+			// extract der encoding of the element
+			$parts[] = substr($data, $idx, $offset - $idx + $length);
+			// update offset over content
+			$offset += $length;
+		}
+		return $parts;
+	}
 
-    /**
-     * Get self with an element at the given index replaced by another.
-     *
-     * @param int     $idx Element index
-     * @param Element $el  New element to insert into the structure
-     *
-     * @throws \OutOfBoundsException
-     *
-     * @return self
-     */
-    public function withReplaced(int $idx, Element $el): self
-    {
-        if (!isset($this->_elements[$idx])) {
-            throw new \OutOfBoundsException(
-                "Structure doesn't have element at index {$idx}.");
-        }
-        $obj = clone $this;
-        $obj->_elements[$idx] = $el;
-        return $obj;
-    }
+	/**
+	 * Get self with an element at the given index replaced by another.
+	 *
+	 * @param int     $idx Element index
+	 * @param Element $el  New element to insert into the structure
+	 *
+	 * @throws \OutOfBoundsException
+	 *
+	 * @return self
+	 */
+	public function withReplaced(int $idx, Element $el): self
+	{
+		if (!isset($this->_elements[$idx])) {
+			throw new \OutOfBoundsException(
+				"Structure doesn't have element at index {$idx}.");
+		}
+		$obj = clone $this;
+		$obj->_elements[$idx] = $el;
+		return $obj;
+	}
 
-    /**
-     * Get self with an element inserted before the given index.
-     *
-     * @param int     $idx Element index
-     * @param Element $el  New element to insert into the structure
-     *
-     * @throws \OutOfBoundsException
-     *
-     * @return self
-     */
-    public function withInserted(int $idx, Element $el): self
-    {
-        if (count($this->_elements) < $idx || $idx < 0) {
-            throw new \OutOfBoundsException("Index {$idx} is out of bounds.");
-        }
-        $obj = clone $this;
-        array_splice($obj->_elements, $idx, 0, [$el]);
-        return $obj;
-    }
+	/**
+	 * Get self with an element inserted before the given index.
+	 *
+	 * @param int     $idx Element index
+	 * @param Element $el  New element to insert into the structure
+	 *
+	 * @throws \OutOfBoundsException
+	 *
+	 * @return self
+	 */
+	public function withInserted(int $idx, Element $el): self
+	{
+		if (count($this->_elements) < $idx || $idx < 0) {
+			throw new \OutOfBoundsException("Index {$idx} is out of bounds.");
+		}
+		$obj = clone $this;
+		array_splice($obj->_elements, $idx, 0, [$el]);
+		return $obj;
+	}
 
-    /**
-     * Get self with an element appended to the end.
-     *
-     * @param Element $el Element to insert into the structure
-     *
-     * @return self
-     */
-    public function withAppended(Element $el): self
-    {
-        $obj = clone $this;
-        array_push($obj->_elements, $el);
-        return $obj;
-    }
+	/**
+	 * Get self with an element appended to the end.
+	 *
+	 * @param Element $el Element to insert into the structure
+	 *
+	 * @return self
+	 */
+	public function withAppended(Element $el): self
+	{
+		$obj = clone $this;
+		array_push($obj->_elements, $el);
+		return $obj;
+	}
 
-    /**
-     * Get self with an element prepended in the beginning.
-     *
-     * @param Element $el Element to insert into the structure
-     *
-     * @return self
-     */
-    public function withPrepended(Element $el): self
-    {
-        $obj = clone $this;
-        array_unshift($obj->_elements, $el);
-        return $obj;
-    }
+	/**
+	 * Get self with an element prepended in the beginning.
+	 *
+	 * @param Element $el Element to insert into the structure
+	 *
+	 * @return self
+	 */
+	public function withPrepended(Element $el): self
+	{
+		$obj = clone $this;
+		array_unshift($obj->_elements, $el);
+		return $obj;
+	}
 
-    /**
-     * Get self with an element at the given index removed.
-     *
-     * @param int $idx Element index
-     *
-     * @throws \OutOfBoundsException
-     *
-     * @return self
-     */
-    public function withoutElement(int $idx): self
-    {
-        if (!isset($this->_elements[$idx])) {
-            throw new \OutOfBoundsException(
-                "Structure doesn't have element at index {$idx}.");
-        }
-        $obj = clone $this;
-        array_splice($obj->_elements, $idx, 1);
-        return $obj;
-    }
+	/**
+	 * Get self with an element at the given index removed.
+	 *
+	 * @param int $idx Element index
+	 *
+	 * @throws \OutOfBoundsException
+	 *
+	 * @return self
+	 */
+	public function withoutElement(int $idx): self
+	{
+		if (!isset($this->_elements[$idx])) {
+			throw new \OutOfBoundsException(
+				"Structure doesn't have element at index {$idx}.");
+		}
+		$obj = clone $this;
+		array_splice($obj->_elements, $idx, 1);
+		return $obj;
+	}
 
-    /**
-     * Get elements in the structure.
-     *
-     * @return UnspecifiedType[]
-     */
-    public function elements(): array
-    {
-        if (!isset($this->_unspecifiedTypes)) {
-            $this->_unspecifiedTypes = array_map(
-                function (Element $el) {
-                    return new UnspecifiedType($el);
-                }, $this->_elements);
-        }
-        return $this->_unspecifiedTypes;
-    }
+	/**
+	 * Get elements in the structure.
+	 *
+	 * @return UnspecifiedType[]
+	 */
+	public function elements(): array
+	{
+		if (!isset($this->_unspecifiedTypes)) {
+			$this->_unspecifiedTypes = array_map(
+				function (Element $el) {
+					return new UnspecifiedType($el);
+				}, $this->_elements);
+		}
+		return $this->_unspecifiedTypes;
+	}
 
-    /**
-     * Check whether the structure has an element at the given index, optionally
-     * satisfying given tag expectation.
-     *
-     * @param int      $idx         Index 0..n
-     * @param null|int $expectedTag Optional type tag expectation
-     *
-     * @return bool
-     */
-    public function has(int $idx, ?int $expectedTag = null): bool
-    {
-        if (!isset($this->_elements[$idx])) {
-            return false;
-        }
-        if (isset($expectedTag)) {
-            if (!$this->_elements[$idx]->isType($expectedTag)) {
-                return false;
-            }
-        }
-        return true;
-    }
+	/**
+	 * Check whether the structure has an element at the given index, optionally
+	 * satisfying given tag expectation.
+	 *
+	 * @param int      $idx         Index 0..n
+	 * @param null|int $expectedTag Optional type tag expectation
+	 *
+	 * @return bool
+	 */
+	public function has(int $idx, ?int $expectedTag = null): bool
+	{
+		if (!isset($this->_elements[$idx])) {
+			return false;
+		}
+		if (isset($expectedTag)) {
+			if (!$this->_elements[$idx]->isType($expectedTag)) {
+				return false;
+			}
+		}
+		return true;
+	}
 
-    /**
-     * Get the element at the given index, optionally checking that the element
-     * has a given tag.
-     *
-     * @param int $idx Index 0..n
-     *
-     * @throws \OutOfBoundsException     If element doesn't exists
-     * @throws \UnexpectedValueException If expectation fails
-     *
-     * @return UnspecifiedType
-     */
-    public function at(int $idx): UnspecifiedType
-    {
-        if (!isset($this->_elements[$idx])) {
-            throw new \OutOfBoundsException(
-                "Structure doesn't have an element at index {$idx}.");
-        }
-        return new UnspecifiedType($this->_elements[$idx]);
-    }
+	/**
+	 * Get the element at the given index, optionally checking that the element
+	 * has a given tag.
+	 *
+	 * @param int $idx Index 0..n
+	 *
+	 * @throws \OutOfBoundsException     If element doesn't exists
+	 * @throws \UnexpectedValueException If expectation fails
+	 *
+	 * @return UnspecifiedType
+	 */
+	public function at(int $idx): UnspecifiedType
+	{
+		if (!isset($this->_elements[$idx])) {
+			throw new \OutOfBoundsException(
+				"Structure doesn't have an element at index {$idx}.");
+		}
+		return new UnspecifiedType($this->_elements[$idx]);
+	}
 
-    /**
-     * Check whether the structure contains a context specific element with a
-     * given tag.
-     *
-     * @param int $tag Tag number
-     *
-     * @return bool
-     */
-    public function hasTagged(int $tag): bool
-    {
-        // lazily build lookup map
-        if (!isset($this->_taggedMap)) {
-            $this->_taggedMap = [];
-            foreach ($this->_elements as $element) {
-                if ($element->isTagged()) {
-                    $this->_taggedMap[$element->tag()] = $element;
-                }
-            }
-        }
-        return isset($this->_taggedMap[$tag]);
-    }
+	/**
+	 * Check whether the structure contains a context specific element with a
+	 * given tag.
+	 *
+	 * @param int $tag Tag number
+	 *
+	 * @return bool
+	 */
+	public function hasTagged(int $tag): bool
+	{
+		// lazily build lookup map
+		if (!isset($this->_taggedMap)) {
+			$this->_taggedMap = [];
+			foreach ($this->_elements as $element) {
+				if ($element->isTagged()) {
+					$this->_taggedMap[$element->tag()] = $element;
+				}
+			}
+		}
+		return isset($this->_taggedMap[$tag]);
+	}
 
-    /**
-     * Get a context specific element tagged with a given tag.
-     *
-     * @param int $tag
-     *
-     * @throws \LogicException If tag doesn't exists
-     *
-     * @return TaggedType
-     */
-    public function getTagged(int $tag): TaggedType
-    {
-        if (!$this->hasTagged($tag)) {
-            throw new \LogicException("No tagged element for tag {$tag}.");
-        }
-        return $this->_taggedMap[$tag];
-    }
+	/**
+	 * Get a context specific element tagged with a given tag.
+	 *
+	 * @param int $tag
+	 *
+	 * @throws \LogicException If tag doesn't exists
+	 *
+	 * @return TaggedType
+	 */
+	public function getTagged(int $tag): TaggedType
+	{
+		if (!$this->hasTagged($tag)) {
+			throw new \LogicException("No tagged element for tag {$tag}.");
+		}
+		return $this->_taggedMap[$tag];
+	}
 
-    /**
-     * @see \Countable::count()
-     *
-     * @return int
-     */
-    public function count(): int
-    {
-        return count($this->_elements);
-    }
+	/**
+	 * @see \Countable::count()
+	 *
+	 * @return int
+	 */
+	public function count(): int
+	{
+		return count($this->_elements);
+	}
 
-    /**
-     * Get an iterator for the UnspecifiedElement objects.
-     *
-     * @see \IteratorAggregate::getIterator()
-     *
-     * @return \ArrayIterator
-     */
-    public function getIterator(): \ArrayIterator
-    {
-        return new \ArrayIterator($this->elements());
-    }
+	/**
+	 * Get an iterator for the UnspecifiedElement objects.
+	 *
+	 * @see \IteratorAggregate::getIterator()
+	 *
+	 * @return \ArrayIterator
+	 */
+	public function getIterator(): \ArrayIterator
+	{
+		return new \ArrayIterator($this->elements());
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function _encodedContentDER(): string
-    {
-        $data = '';
-        foreach ($this->_elements as $element) {
-            $data .= $element->toDER();
-        }
-        return $data;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function _encodedContentDER(): string
+	{
+		$data = '';
+		foreach ($this->_elements as $element) {
+			$data .= $element->toDER();
+		}
+		return $data;
+	}
 
-    /**
-     * {@inheritdoc}
-     *
-     * @return self
-     */
-    protected static function _decodeFromDER(Identifier $identifier,
-        string $data, int &$offset): ElementBase
-    {
-        if (!$identifier->isConstructed()) {
-            throw new DecodeException(
-                'Structured element must have constructed bit set.');
-        }
-        $idx = $offset;
-        $length = Length::expectFromDER($data, $idx);
-        if ($length->isIndefinite()) {
-            $type = self::_decodeIndefiniteLength($data, $idx);
-        } else {
-            $type = self::_decodeDefiniteLength($data, $idx,
-                $length->intLength());
-        }
-        $offset = $idx;
-        return $type;
-    }
+	/**
+	 * {@inheritdoc}
+	 *
+	 * @return self
+	 */
+	protected static function _decodeFromDER(Identifier $identifier,
+		string $data, int &$offset): ElementBase
+	{
+		if (!$identifier->isConstructed()) {
+			throw new DecodeException(
+				'Structured element must have constructed bit set.');
+		}
+		$idx = $offset;
+		$length = Length::expectFromDER($data, $idx);
+		if ($length->isIndefinite()) {
+			$type = self::_decodeIndefiniteLength($data, $idx);
+		} else {
+			$type = self::_decodeDefiniteLength($data, $idx,
+				$length->intLength());
+		}
+		$offset = $idx;
+		return $type;
+	}
 
-    /**
-     * Decode elements for a definite length.
-     *
-     * @param string $data   DER data
-     * @param int    $offset Offset to data
-     * @param int    $length Number of bytes to decode
-     *
-     * @throws DecodeException
-     *
-     * @return ElementBase
-     */
-    private static function _decodeDefiniteLength(string $data, int &$offset,
-        int $length): ElementBase
-    {
-        $idx = $offset;
-        $end = $idx + $length;
-        $elements = [];
-        while ($idx < $end) {
-            $elements[] = Element::fromDER($data, $idx);
-            // check that element didn't overflow length
-            if ($idx > $end) {
-                throw new DecodeException(
-                    "Structure's content overflows length.");
-            }
-        }
-        $offset = $idx;
-        // return instance by static late binding
-        return new static(...$elements);
-    }
+	/**
+	 * Decode elements for a definite length.
+	 *
+	 * @param string $data   DER data
+	 * @param int    $offset Offset to data
+	 * @param int    $length Number of bytes to decode
+	 *
+	 * @throws DecodeException
+	 *
+	 * @return ElementBase
+	 */
+	private static function _decodeDefiniteLength(string $data, int &$offset,
+		int $length): ElementBase
+	{
+		$idx = $offset;
+		$end = $idx + $length;
+		$elements = [];
+		while ($idx < $end) {
+			$elements[] = Element::fromDER($data, $idx);
+			// check that element didn't overflow length
+			if ($idx > $end) {
+				throw new DecodeException(
+					"Structure's content overflows length.");
+			}
+		}
+		$offset = $idx;
+		// return instance by static late binding
+		return new static(...$elements);
+	}
 
-    /**
-     * Decode elements for an indefinite length.
-     *
-     * @param string $data   DER data
-     * @param int    $offset Offset to data
-     *
-     * @throws DecodeException
-     *
-     * @return ElementBase
-     */
-    private static function _decodeIndefiniteLength(
-        string $data, int &$offset): ElementBase
-    {
-        $idx = $offset;
-        $elements = [];
-        $end = strlen($data);
-        while (true) {
-            if ($idx >= $end) {
-                throw new DecodeException(
-                    'Unexpected end of data while decoding indefinite length structure.');
-            }
-            $el = Element::fromDER($data, $idx);
-            if ($el->isType(self::TYPE_EOC)) {
-                break;
-            }
-            $elements[] = $el;
-        }
-        $offset = $idx;
-        $type = new static(...$elements);
-        $type->_indefiniteLength = true;
-        return $type;
-    }
+	/**
+	 * Decode elements for an indefinite length.
+	 *
+	 * @param string $data   DER data
+	 * @param int    $offset Offset to data
+	 *
+	 * @throws DecodeException
+	 *
+	 * @return ElementBase
+	 */
+	private static function _decodeIndefiniteLength(
+		string $data, int &$offset): ElementBase
+	{
+		$idx = $offset;
+		$elements = [];
+		$end = strlen($data);
+		while (true) {
+			if ($idx >= $end) {
+				throw new DecodeException(
+					'Unexpected end of data while decoding indefinite length structure.');
+			}
+			$el = Element::fromDER($data, $idx);
+			if ($el->isType(self::TYPE_EOC)) {
+				break;
+			}
+			$elements[] = $el;
+		}
+		$offset = $idx;
+		$type = new static(...$elements);
+		$type->_indefiniteLength = true;
+		return $type;
+	}
 }

lib/ASN1/Type/Tagged/ImplicitlyTaggedType.php

Indentation +45 added lines, -45 removed lines

@@ -17,52 +17,52 @@
  */
 class ImplicitlyTaggedType extends TaggedTypeWrap implements ImplicitTagging
 {
-    /**
-     * Constructor.
-     *
-     * @param int     $tag     Tag number
-     * @param Element $element Wrapped element
-     * @param int     $class   Type class
-     */
-    public function __construct(int $tag, Element $element,
-        int $class = Identifier::CLASS_CONTEXT_SPECIFIC)
-    {
-        $this->_typeTag = $tag;
-        $this->_element = $element;
-        $this->_class = $class;
-    }
+	/**
+	 * Constructor.
+	 *
+	 * @param int     $tag     Tag number
+	 * @param Element $element Wrapped element
+	 * @param int     $class   Type class
+	 */
+	public function __construct(int $tag, Element $element,
+		int $class = Identifier::CLASS_CONTEXT_SPECIFIC)
+	{
+		$this->_typeTag = $tag;
+		$this->_element = $element;
+		$this->_class = $class;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function isConstructed(): bool
-    {
-        // depends on the underlying type
-        return $this->_element->isConstructed();
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isConstructed(): bool
+	{
+		// depends on the underlying type
+		return $this->_element->isConstructed();
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function implicit(
-        int $tag, int $class = Identifier::CLASS_UNIVERSAL): UnspecifiedType
-    {
-        $this->_element->expectType($tag);
-        if ($this->_element->typeClass() !== $class) {
-            throw new \UnexpectedValueException(
-                sprintf('Type class %s expected, got %s.',
-                    Identifier::classToName($class),
-                    Identifier::classToName($this->_element->typeClass())));
-        }
-        return $this->_element->asUnspecified();
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function implicit(
+		int $tag, int $class = Identifier::CLASS_UNIVERSAL): UnspecifiedType
+	{
+		$this->_element->expectType($tag);
+		if ($this->_element->typeClass() !== $class) {
+			throw new \UnexpectedValueException(
+				sprintf('Type class %s expected, got %s.',
+					Identifier::classToName($class),
+					Identifier::classToName($this->_element->typeClass())));
+		}
+		return $this->_element->asUnspecified();
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function _encodedContentDER(): string
-    {
-        // get only the content of the wrapped element.
-        return $this->_element->_encodedContentDER();
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function _encodedContentDER(): string
+	{
+		// get only the content of the wrapped element.
+		return $this->_element->_encodedContentDER();
+	}
 }

lib/ASN1/Type/Tagged/TaggedTypeWrap.php

Indentation +19 added lines, -19 removed lines

@@ -11,25 +11,25 @@
  */
 abstract class TaggedTypeWrap extends TaggedType
 {
-    /**
-     * Wrapped element.
-     *
-     * @var \Sop\ASN1\Element
-     */
-    protected $_element;
+	/**
+	 * Wrapped element.
+	 *
+	 * @var \Sop\ASN1\Element
+	 */
+	protected $_element;
 
-    /**
-     * Type class.
-     *
-     * @var int
-     */
-    protected $_class;
+	/**
+	 * Type class.
+	 *
+	 * @var int
+	 */
+	protected $_class;
 
-    /**
-     * {@inheritdoc}
-     */
-    public function typeClass(): int
-    {
-        return $this->_class;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function typeClass(): int
+	{
+		return $this->_class;
+	}
 }

lib/ASN1/Type/UnspecifiedType.php

Indentation +671 added lines, -671 removed lines

@@ -17,675 +17,675 @@
  */
 class UnspecifiedType implements ElementBase
 {
-    /**
-     * The wrapped element.
-     *
-     * @var Element
-     */
-    private $_element;
-
-    /**
-     * Constructor.
-     *
-     * @param Element $el
-     */
-    public function __construct(Element $el)
-    {
-        $this->_element = $el;
-    }
-
-    /**
-     * Initialize from DER data.
-     *
-     * @param string $data DER encoded data
-     *
-     * @return self
-     */
-    public static function fromDER(string $data): self
-    {
-        return Element::fromDER($data)->asUnspecified();
-    }
-
-    /**
-     * Initialize from ElementBase interface.
-     *
-     * @param ElementBase $el
-     *
-     * @return self
-     */
-    public static function fromElementBase(ElementBase $el): self
-    {
-        // if element is already wrapped
-        if ($el instanceof self) {
-            return $el;
-        }
-        return new self($el->asElement());
-    }
-
-    /**
-     * Get the wrapped element as a context specific tagged type.
-     *
-     * @throws \UnexpectedValueException If the element is not tagged
-     *
-     * @return TaggedType
-     */
-    public function asTagged(): TaggedType
-    {
-        if (!$this->_element instanceof TaggedType) {
-            throw new \UnexpectedValueException(
-                'Tagged element expected, got ' . $this->_typeDescriptorString());
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an application specific type.
-     *
-     * @throws \UnexpectedValueException If element is not application specific
-     *
-     * @return \Sop\ASN1\Type\Tagged\ApplicationType
-     */
-    public function asApplication(): Tagged\ApplicationType
-    {
-        if (!$this->_element instanceof Tagged\ApplicationType) {
-            throw new \UnexpectedValueException(
-                'Application type expected, got ' . $this->_typeDescriptorString());
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a private tagged type.
-     *
-     * @throws \UnexpectedValueException If element is not using private tagging
-     *
-     * @return \Sop\ASN1\Type\Tagged\PrivateType
-     */
-    public function asPrivate(): Tagged\PrivateType
-    {
-        if (!$this->_element instanceof Tagged\PrivateType) {
-            throw new \UnexpectedValueException(
-                'Private type expected, got ' . $this->_typeDescriptorString());
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a boolean type.
-     *
-     * @throws \UnexpectedValueException If the element is not a boolean
-     *
-     * @return \Sop\ASN1\Type\Primitive\Boolean
-     */
-    public function asBoolean(): Primitive\Boolean
-    {
-        if (!$this->_element instanceof Primitive\Boolean) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_BOOLEAN));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an integer type.
-     *
-     * @throws \UnexpectedValueException If the element is not an integer
-     *
-     * @return \Sop\ASN1\Type\Primitive\Integer
-     */
-    public function asInteger(): Primitive\Integer
-    {
-        if (!$this->_element instanceof Primitive\Integer) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_INTEGER));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a bit string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a bit string
-     *
-     * @return \Sop\ASN1\Type\Primitive\BitString
-     */
-    public function asBitString(): Primitive\BitString
-    {
-        if (!$this->_element instanceof Primitive\BitString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_BIT_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an octet string type.
-     *
-     * @throws \UnexpectedValueException If the element is not an octet string
-     *
-     * @return \Sop\ASN1\Type\Primitive\OctetString
-     */
-    public function asOctetString(): Primitive\OctetString
-    {
-        if (!$this->_element instanceof Primitive\OctetString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_OCTET_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a null type.
-     *
-     * @throws \UnexpectedValueException If the element is not a null
-     *
-     * @return \Sop\ASN1\Type\Primitive\NullType
-     */
-    public function asNull(): Primitive\NullType
-    {
-        if (!$this->_element instanceof Primitive\NullType) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_NULL));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an object identifier type.
-     *
-     * @throws \UnexpectedValueException If the element is not an object identifier
-     *
-     * @return \Sop\ASN1\Type\Primitive\ObjectIdentifier
-     */
-    public function asObjectIdentifier(): Primitive\ObjectIdentifier
-    {
-        if (!$this->_element instanceof Primitive\ObjectIdentifier) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_OBJECT_IDENTIFIER));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an object descriptor type.
-     *
-     * @throws \UnexpectedValueException If the element is not an object descriptor
-     *
-     * @return \Sop\ASN1\Type\Primitive\ObjectDescriptor
-     */
-    public function asObjectDescriptor(): Primitive\ObjectDescriptor
-    {
-        if (!$this->_element instanceof Primitive\ObjectDescriptor) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_OBJECT_DESCRIPTOR));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a real type.
-     *
-     * @throws \UnexpectedValueException If the element is not a real
-     *
-     * @return \Sop\ASN1\Type\Primitive\Real
-     */
-    public function asReal(): Primitive\Real
-    {
-        if (!$this->_element instanceof Primitive\Real) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_REAL));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an enumerated type.
-     *
-     * @throws \UnexpectedValueException If the element is not an enumerated
-     *
-     * @return \Sop\ASN1\Type\Primitive\Enumerated
-     */
-    public function asEnumerated(): Primitive\Enumerated
-    {
-        if (!$this->_element instanceof Primitive\Enumerated) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_ENUMERATED));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a UTF8 string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a UTF8 string
-     *
-     * @return \Sop\ASN1\Type\Primitive\UTF8String
-     */
-    public function asUTF8String(): Primitive\UTF8String
-    {
-        if (!$this->_element instanceof Primitive\UTF8String) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_UTF8_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a relative OID type.
-     *
-     * @throws \UnexpectedValueException If the element is not a relative OID
-     *
-     * @return \Sop\ASN1\Type\Primitive\RelativeOID
-     */
-    public function asRelativeOID(): Primitive\RelativeOID
-    {
-        if (!$this->_element instanceof Primitive\RelativeOID) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_RELATIVE_OID));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a sequence type.
-     *
-     * @throws \UnexpectedValueException If the element is not a sequence
-     *
-     * @return \Sop\ASN1\Type\Constructed\Sequence
-     */
-    public function asSequence(): Constructed\Sequence
-    {
-        if (!$this->_element instanceof Constructed\Sequence) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_SEQUENCE));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a set type.
-     *
-     * @throws \UnexpectedValueException If the element is not a set
-     *
-     * @return \Sop\ASN1\Type\Constructed\Set
-     */
-    public function asSet(): Constructed\Set
-    {
-        if (!$this->_element instanceof Constructed\Set) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_SET));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a numeric string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a numeric string
-     *
-     * @return \Sop\ASN1\Type\Primitive\NumericString
-     */
-    public function asNumericString(): Primitive\NumericString
-    {
-        if (!$this->_element instanceof Primitive\NumericString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_NUMERIC_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a printable string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a printable
-     *                                   string
-     *
-     * @return \Sop\ASN1\Type\Primitive\PrintableString
-     */
-    public function asPrintableString(): Primitive\PrintableString
-    {
-        if (!$this->_element instanceof Primitive\PrintableString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_PRINTABLE_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a T61 string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a T61 string
-     *
-     * @return \Sop\ASN1\Type\Primitive\T61String
-     */
-    public function asT61String(): Primitive\T61String
-    {
-        if (!$this->_element instanceof Primitive\T61String) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_T61_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a videotex string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a videotex string
-     *
-     * @return \Sop\ASN1\Type\Primitive\VideotexString
-     */
-    public function asVideotexString(): Primitive\VideotexString
-    {
-        if (!$this->_element instanceof Primitive\VideotexString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_VIDEOTEX_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a IA5 string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a IA5 string
-     *
-     * @return \Sop\ASN1\Type\Primitive\IA5String
-     */
-    public function asIA5String(): Primitive\IA5String
-    {
-        if (!$this->_element instanceof Primitive\IA5String) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_IA5_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as an UTC time type.
-     *
-     * @throws \UnexpectedValueException If the element is not a UTC time
-     *
-     * @return \Sop\ASN1\Type\Primitive\UTCTime
-     */
-    public function asUTCTime(): Primitive\UTCTime
-    {
-        if (!$this->_element instanceof Primitive\UTCTime) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_UTC_TIME));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a generalized time type.
-     *
-     * @throws \UnexpectedValueException If the element is not a generalized time
-     *
-     * @return \Sop\ASN1\Type\Primitive\GeneralizedTime
-     */
-    public function asGeneralizedTime(): Primitive\GeneralizedTime
-    {
-        if (!$this->_element instanceof Primitive\GeneralizedTime) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_GENERALIZED_TIME));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a graphic string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a graphic string
-     *
-     * @return \Sop\ASN1\Type\Primitive\GraphicString
-     */
-    public function asGraphicString(): Primitive\GraphicString
-    {
-        if (!$this->_element instanceof Primitive\GraphicString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_GRAPHIC_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a visible string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a visible string
-     *
-     * @return \Sop\ASN1\Type\Primitive\VisibleString
-     */
-    public function asVisibleString(): Primitive\VisibleString
-    {
-        if (!$this->_element instanceof Primitive\VisibleString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_VISIBLE_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a general string type.
-     *
-     * @throws \UnexpectedValueException If the element is not general string
-     *
-     * @return \Sop\ASN1\Type\Primitive\GeneralString
-     */
-    public function asGeneralString(): Primitive\GeneralString
-    {
-        if (!$this->_element instanceof Primitive\GeneralString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_GENERAL_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a universal string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a universal string
-     *
-     * @return \Sop\ASN1\Type\Primitive\UniversalString
-     */
-    public function asUniversalString(): Primitive\UniversalString
-    {
-        if (!$this->_element instanceof Primitive\UniversalString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_UNIVERSAL_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a character string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a character string
-     *
-     * @return \Sop\ASN1\Type\Primitive\CharacterString
-     */
-    public function asCharacterString(): Primitive\CharacterString
-    {
-        if (!$this->_element instanceof Primitive\CharacterString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_CHARACTER_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a BMP string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a bmp string
-     *
-     * @return \Sop\ASN1\Type\Primitive\BMPString
-     */
-    public function asBMPString(): Primitive\BMPString
-    {
-        if (!$this->_element instanceof Primitive\BMPString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_BMP_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as a constructed string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a constructed string
-     *
-     * @return \Sop\ASN1\Type\Constructed\ConstructedString
-     */
-    public function asConstructedString(): Constructed\ConstructedString
-    {
-        if (!$this->_element instanceof Constructed\ConstructedString) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_CONSTRUCTED_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as any string type.
-     *
-     * @throws \UnexpectedValueException If the element is not a string
-     *
-     * @return StringType
-     */
-    public function asString(): StringType
-    {
-        if (!$this->_element instanceof StringType) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_STRING));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * Get the wrapped element as any time type.
-     *
-     * @throws \UnexpectedValueException If the element is not a time
-     *
-     * @return TimeType
-     */
-    public function asTime(): TimeType
-    {
-        if (!$this->_element instanceof TimeType) {
-            throw new \UnexpectedValueException(
-                $this->_generateExceptionMessage(Element::TYPE_TIME));
-        }
-        return $this->_element;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function toDER(): string
-    {
-        return $this->_element->toDER();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function typeClass(): int
-    {
-        return $this->_element->typeClass();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function isConstructed(): bool
-    {
-        return $this->_element->isConstructed();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function tag(): int
-    {
-        return $this->_element->tag();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function isType(int $tag): bool
-    {
-        return $this->_element->isType($tag);
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * Consider using any of the <code>as*</code> accessor methods instead.
-     */
-    public function expectType(int $tag): ElementBase
-    {
-        return $this->_element->expectType($tag);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function isTagged(): bool
-    {
-        return $this->_element->isTagged();
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * Consider using <code>asTagged()</code> method instead and chaining
-     * with <code>TaggedType::asExplicit()</code> or
-     * <code>TaggedType::asImplicit()</code>.
-     */
-    public function expectTagged(?int $tag = null): TaggedType
-    {
-        return $this->_element->expectTagged($tag);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function asElement(): Element
-    {
-        return $this->_element;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function asUnspecified(): UnspecifiedType
-    {
-        return $this;
-    }
-
-    /**
-     * Generate message for exceptions thrown by <code>as*</code> methods.
-     *
-     * @param int $tag Type tag of the expected element
-     *
-     * @return string
-     */
-    private function _generateExceptionMessage(int $tag): string
-    {
-        return sprintf('%s expected, got %s.', Element::tagToName($tag),
-            $this->_typeDescriptorString());
-    }
-
-    /**
-     * Get textual description of the wrapped element for debugging purposes.
-     *
-     * @return string
-     */
-    private function _typeDescriptorString(): string
-    {
-        $type_cls = $this->_element->typeClass();
-        $tag = $this->_element->tag();
-        if (Identifier::CLASS_UNIVERSAL === $type_cls) {
-            return Element::tagToName($tag);
-        }
-        return Identifier::classToName($type_cls) . " TAG {$tag}";
-    }
+	/**
+	 * The wrapped element.
+	 *
+	 * @var Element
+	 */
+	private $_element;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param Element $el
+	 */
+	public function __construct(Element $el)
+	{
+		$this->_element = $el;
+	}
+
+	/**
+	 * Initialize from DER data.
+	 *
+	 * @param string $data DER encoded data
+	 *
+	 * @return self
+	 */
+	public static function fromDER(string $data): self
+	{
+		return Element::fromDER($data)->asUnspecified();
+	}
+
+	/**
+	 * Initialize from ElementBase interface.
+	 *
+	 * @param ElementBase $el
+	 *
+	 * @return self
+	 */
+	public static function fromElementBase(ElementBase $el): self
+	{
+		// if element is already wrapped
+		if ($el instanceof self) {
+			return $el;
+		}
+		return new self($el->asElement());
+	}
+
+	/**
+	 * Get the wrapped element as a context specific tagged type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not tagged
+	 *
+	 * @return TaggedType
+	 */
+	public function asTagged(): TaggedType
+	{
+		if (!$this->_element instanceof TaggedType) {
+			throw new \UnexpectedValueException(
+				'Tagged element expected, got ' . $this->_typeDescriptorString());
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an application specific type.
+	 *
+	 * @throws \UnexpectedValueException If element is not application specific
+	 *
+	 * @return \Sop\ASN1\Type\Tagged\ApplicationType
+	 */
+	public function asApplication(): Tagged\ApplicationType
+	{
+		if (!$this->_element instanceof Tagged\ApplicationType) {
+			throw new \UnexpectedValueException(
+				'Application type expected, got ' . $this->_typeDescriptorString());
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a private tagged type.
+	 *
+	 * @throws \UnexpectedValueException If element is not using private tagging
+	 *
+	 * @return \Sop\ASN1\Type\Tagged\PrivateType
+	 */
+	public function asPrivate(): Tagged\PrivateType
+	{
+		if (!$this->_element instanceof Tagged\PrivateType) {
+			throw new \UnexpectedValueException(
+				'Private type expected, got ' . $this->_typeDescriptorString());
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a boolean type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a boolean
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\Boolean
+	 */
+	public function asBoolean(): Primitive\Boolean
+	{
+		if (!$this->_element instanceof Primitive\Boolean) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_BOOLEAN));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an integer type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not an integer
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\Integer
+	 */
+	public function asInteger(): Primitive\Integer
+	{
+		if (!$this->_element instanceof Primitive\Integer) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_INTEGER));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a bit string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a bit string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\BitString
+	 */
+	public function asBitString(): Primitive\BitString
+	{
+		if (!$this->_element instanceof Primitive\BitString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_BIT_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an octet string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not an octet string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\OctetString
+	 */
+	public function asOctetString(): Primitive\OctetString
+	{
+		if (!$this->_element instanceof Primitive\OctetString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_OCTET_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a null type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a null
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\NullType
+	 */
+	public function asNull(): Primitive\NullType
+	{
+		if (!$this->_element instanceof Primitive\NullType) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_NULL));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an object identifier type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not an object identifier
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\ObjectIdentifier
+	 */
+	public function asObjectIdentifier(): Primitive\ObjectIdentifier
+	{
+		if (!$this->_element instanceof Primitive\ObjectIdentifier) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_OBJECT_IDENTIFIER));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an object descriptor type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not an object descriptor
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\ObjectDescriptor
+	 */
+	public function asObjectDescriptor(): Primitive\ObjectDescriptor
+	{
+		if (!$this->_element instanceof Primitive\ObjectDescriptor) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_OBJECT_DESCRIPTOR));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a real type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a real
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\Real
+	 */
+	public function asReal(): Primitive\Real
+	{
+		if (!$this->_element instanceof Primitive\Real) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_REAL));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an enumerated type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not an enumerated
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\Enumerated
+	 */
+	public function asEnumerated(): Primitive\Enumerated
+	{
+		if (!$this->_element instanceof Primitive\Enumerated) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_ENUMERATED));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a UTF8 string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a UTF8 string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\UTF8String
+	 */
+	public function asUTF8String(): Primitive\UTF8String
+	{
+		if (!$this->_element instanceof Primitive\UTF8String) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_UTF8_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a relative OID type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a relative OID
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\RelativeOID
+	 */
+	public function asRelativeOID(): Primitive\RelativeOID
+	{
+		if (!$this->_element instanceof Primitive\RelativeOID) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_RELATIVE_OID));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a sequence type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a sequence
+	 *
+	 * @return \Sop\ASN1\Type\Constructed\Sequence
+	 */
+	public function asSequence(): Constructed\Sequence
+	{
+		if (!$this->_element instanceof Constructed\Sequence) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_SEQUENCE));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a set type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a set
+	 *
+	 * @return \Sop\ASN1\Type\Constructed\Set
+	 */
+	public function asSet(): Constructed\Set
+	{
+		if (!$this->_element instanceof Constructed\Set) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_SET));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a numeric string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a numeric string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\NumericString
+	 */
+	public function asNumericString(): Primitive\NumericString
+	{
+		if (!$this->_element instanceof Primitive\NumericString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_NUMERIC_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a printable string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a printable
+	 *                                   string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\PrintableString
+	 */
+	public function asPrintableString(): Primitive\PrintableString
+	{
+		if (!$this->_element instanceof Primitive\PrintableString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_PRINTABLE_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a T61 string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a T61 string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\T61String
+	 */
+	public function asT61String(): Primitive\T61String
+	{
+		if (!$this->_element instanceof Primitive\T61String) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_T61_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a videotex string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a videotex string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\VideotexString
+	 */
+	public function asVideotexString(): Primitive\VideotexString
+	{
+		if (!$this->_element instanceof Primitive\VideotexString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_VIDEOTEX_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a IA5 string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a IA5 string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\IA5String
+	 */
+	public function asIA5String(): Primitive\IA5String
+	{
+		if (!$this->_element instanceof Primitive\IA5String) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_IA5_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as an UTC time type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a UTC time
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\UTCTime
+	 */
+	public function asUTCTime(): Primitive\UTCTime
+	{
+		if (!$this->_element instanceof Primitive\UTCTime) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_UTC_TIME));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a generalized time type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a generalized time
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\GeneralizedTime
+	 */
+	public function asGeneralizedTime(): Primitive\GeneralizedTime
+	{
+		if (!$this->_element instanceof Primitive\GeneralizedTime) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_GENERALIZED_TIME));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a graphic string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a graphic string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\GraphicString
+	 */
+	public function asGraphicString(): Primitive\GraphicString
+	{
+		if (!$this->_element instanceof Primitive\GraphicString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_GRAPHIC_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a visible string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a visible string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\VisibleString
+	 */
+	public function asVisibleString(): Primitive\VisibleString
+	{
+		if (!$this->_element instanceof Primitive\VisibleString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_VISIBLE_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a general string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not general string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\GeneralString
+	 */
+	public function asGeneralString(): Primitive\GeneralString
+	{
+		if (!$this->_element instanceof Primitive\GeneralString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_GENERAL_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a universal string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a universal string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\UniversalString
+	 */
+	public function asUniversalString(): Primitive\UniversalString
+	{
+		if (!$this->_element instanceof Primitive\UniversalString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_UNIVERSAL_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a character string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a character string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\CharacterString
+	 */
+	public function asCharacterString(): Primitive\CharacterString
+	{
+		if (!$this->_element instanceof Primitive\CharacterString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_CHARACTER_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a BMP string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a bmp string
+	 *
+	 * @return \Sop\ASN1\Type\Primitive\BMPString
+	 */
+	public function asBMPString(): Primitive\BMPString
+	{
+		if (!$this->_element instanceof Primitive\BMPString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_BMP_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as a constructed string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a constructed string
+	 *
+	 * @return \Sop\ASN1\Type\Constructed\ConstructedString
+	 */
+	public function asConstructedString(): Constructed\ConstructedString
+	{
+		if (!$this->_element instanceof Constructed\ConstructedString) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_CONSTRUCTED_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as any string type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a string
+	 *
+	 * @return StringType
+	 */
+	public function asString(): StringType
+	{
+		if (!$this->_element instanceof StringType) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_STRING));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * Get the wrapped element as any time type.
+	 *
+	 * @throws \UnexpectedValueException If the element is not a time
+	 *
+	 * @return TimeType
+	 */
+	public function asTime(): TimeType
+	{
+		if (!$this->_element instanceof TimeType) {
+			throw new \UnexpectedValueException(
+				$this->_generateExceptionMessage(Element::TYPE_TIME));
+		}
+		return $this->_element;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function toDER(): string
+	{
+		return $this->_element->toDER();
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function typeClass(): int
+	{
+		return $this->_element->typeClass();
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isConstructed(): bool
+	{
+		return $this->_element->isConstructed();
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function tag(): int
+	{
+		return $this->_element->tag();
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isType(int $tag): bool
+	{
+		return $this->_element->isType($tag);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 *
+	 * Consider using any of the <code>as*</code> accessor methods instead.
+	 */
+	public function expectType(int $tag): ElementBase
+	{
+		return $this->_element->expectType($tag);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function isTagged(): bool
+	{
+		return $this->_element->isTagged();
+	}
+
+	/**
+	 * {@inheritdoc}
+	 *
+	 * Consider using <code>asTagged()</code> method instead and chaining
+	 * with <code>TaggedType::asExplicit()</code> or
+	 * <code>TaggedType::asImplicit()</code>.
+	 */
+	public function expectTagged(?int $tag = null): TaggedType
+	{
+		return $this->_element->expectTagged($tag);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function asElement(): Element
+	{
+		return $this->_element;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function asUnspecified(): UnspecifiedType
+	{
+		return $this;
+	}
+
+	/**
+	 * Generate message for exceptions thrown by <code>as*</code> methods.
+	 *
+	 * @param int $tag Type tag of the expected element
+	 *
+	 * @return string
+	 */
+	private function _generateExceptionMessage(int $tag): string
+	{
+		return sprintf('%s expected, got %s.', Element::tagToName($tag),
+			$this->_typeDescriptorString());
+	}
+
+	/**
+	 * Get textual description of the wrapped element for debugging purposes.
+	 *
+	 * @return string
+	 */
+	private function _typeDescriptorString(): string
+	{
+		$type_cls = $this->_element->typeClass();
+		$tag = $this->_element->tag();
+		if (Identifier::CLASS_UNIVERSAL === $type_cls) {
+			return Element::tagToName($tag);
+		}
+		return Identifier::classToName($type_cls) . " TAG {$tag}";
+	}
 }