mirror of
https://github.com/danog/phpseclib.git
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1324 lines
52 KiB
PHP
1324 lines
52 KiB
PHP
<?php
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/**
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* Pure-PHP ASN.1 Parser
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*
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* PHP version 5
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*
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* ASN.1 provides the semantics for data encoded using various schemes. The most commonly
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* utilized scheme is DER or the "Distinguished Encoding Rules". PEM's are base64 encoded
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* DER blobs.
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*
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* \phpseclib\File\ASN1 decodes and encodes DER formatted messages and places them in a semantic context.
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*
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* Uses the 1988 ASN.1 syntax.
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*
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* @category File
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* @package ASN1
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* @author Jim Wigginton <terrafrost@php.net>
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* @copyright 2012 Jim Wigginton
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* @license http://www.opensource.org/licenses/mit-license.html MIT License
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* @link http://phpseclib.sourceforge.net
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*/
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namespace phpseclib\File;
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use phpseclib\File\ASN1\Element;
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use phpseclib\Math\BigInteger;
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/**
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* Pure-PHP ASN.1 Parser
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*
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* @package ASN1
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* @author Jim Wigginton <terrafrost@php.net>
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* @access public
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*/
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class ASN1
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{
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/**#@+
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* Tag Classes
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*
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* @access private
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* @link http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#page=12
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*/
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const CLASS_UNIVERSAL = 0;
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const CLASS_APPLICATION = 1;
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const CLASS_CONTEXT_SPECIFIC = 2;
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const CLASS_PRIVATE = 3;
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/**#@-*/
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/**#@+
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* Tag Classes
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*
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* @access private
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* @link http://www.obj-sys.com/asn1tutorial/node124.html
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*/
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const TYPE_BOOLEAN = 1;
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const TYPE_INTEGER = 2;
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const TYPE_BIT_STRING = 3;
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const TYPE_OCTET_STRING = 4;
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const TYPE_NULL = 5;
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const TYPE_OBJECT_IDENTIFIER = 6;
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//const TYPE_OBJECT_DESCRIPTOR = 7;
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//const TYPE_INSTANCE_OF = 8; // EXTERNAL
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const TYPE_REAL = 9;
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const TYPE_ENUMERATED = 10;
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//const TYPE_EMBEDDED = 11;
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const TYPE_UTF8_STRING = 12;
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//const TYPE_RELATIVE_OID = 13;
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const TYPE_SEQUENCE = 16; // SEQUENCE OF
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const TYPE_SET = 17; // SET OF
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/**#@-*/
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/**#@+
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* More Tag Classes
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*
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* @access private
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* @link http://www.obj-sys.com/asn1tutorial/node10.html
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*/
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const TYPE_NUMERIC_STRING = 18;
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const TYPE_PRINTABLE_STRING = 19;
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const TYPE_TELETEX_STRING = 20; // T61String
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const TYPE_VIDEOTEX_STRING = 21;
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const TYPE_IA5_STRING = 22;
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const TYPE_UTC_TIME = 23;
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const TYPE_GENERALIZED_TIME = 24;
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const TYPE_GRAPHIC_STRING = 25;
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const TYPE_VISIBLE_STRING = 26; // ISO646String
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const TYPE_GENERAL_STRING = 27;
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const TYPE_UNIVERSAL_STRING = 28;
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//const TYPE_CHARACTER_STRING = 29;
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const TYPE_BMP_STRING = 30;
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/**#@-*/
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/**#@+
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* Tag Aliases
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*
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* These tags are kinda place holders for other tags.
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*
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* @access private
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*/
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const TYPE_CHOICE = -1;
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const TYPE_ANY = -2;
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/**#@-*/
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/**
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* ASN.1 object identifier
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*
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* @var array
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* @access private
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* @link http://en.wikipedia.org/wiki/Object_identifier
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*/
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var $oids = array();
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/**
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* Default date format
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*
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* @var string
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* @access private
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* @link http://php.net/class.datetime
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*/
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var $format = 'D, d M Y H:i:s O';
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/**
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* Default date format
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*
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* @var array
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* @access private
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* @see self::setTimeFormat()
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* @see self::asn1map()
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* @link http://php.net/class.datetime
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*/
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var $encoded;
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/**
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* Filters
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*
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* If the mapping type is self::TYPE_ANY what do we actually encode it as?
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*
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* @var array
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* @access private
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* @see self::_encode_der()
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*/
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var $filters;
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/**
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* Type mapping table for the ANY type.
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*
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* Structured or unknown types are mapped to a \phpseclib\File\ASN1\Element.
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* Unambiguous types get the direct mapping (int/real/bool).
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* Others are mapped as a choice, with an extra indexing level.
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*
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* @var array
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* @access public
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*/
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var $ANYmap = array(
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self::TYPE_BOOLEAN => true,
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self::TYPE_INTEGER => true,
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self::TYPE_BIT_STRING => 'bitString',
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self::TYPE_OCTET_STRING => 'octetString',
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self::TYPE_NULL => 'null',
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self::TYPE_OBJECT_IDENTIFIER => 'objectIdentifier',
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self::TYPE_REAL => true,
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self::TYPE_ENUMERATED => 'enumerated',
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self::TYPE_UTF8_STRING => 'utf8String',
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self::TYPE_NUMERIC_STRING => 'numericString',
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self::TYPE_PRINTABLE_STRING => 'printableString',
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self::TYPE_TELETEX_STRING => 'teletexString',
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self::TYPE_VIDEOTEX_STRING => 'videotexString',
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self::TYPE_IA5_STRING => 'ia5String',
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self::TYPE_UTC_TIME => 'utcTime',
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self::TYPE_GENERALIZED_TIME => 'generalTime',
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self::TYPE_GRAPHIC_STRING => 'graphicString',
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self::TYPE_VISIBLE_STRING => 'visibleString',
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self::TYPE_GENERAL_STRING => 'generalString',
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self::TYPE_UNIVERSAL_STRING => 'universalString',
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//self::TYPE_CHARACTER_STRING => 'characterString',
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self::TYPE_BMP_STRING => 'bmpString'
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);
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/**
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* String type to character size mapping table.
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*
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* Non-convertable types are absent from this table.
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* size == 0 indicates variable length encoding.
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*
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* @var array
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* @access public
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*/
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var $stringTypeSize = array(
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self::TYPE_UTF8_STRING => 0,
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self::TYPE_BMP_STRING => 2,
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self::TYPE_UNIVERSAL_STRING => 4,
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self::TYPE_PRINTABLE_STRING => 1,
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self::TYPE_TELETEX_STRING => 1,
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self::TYPE_IA5_STRING => 1,
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self::TYPE_VISIBLE_STRING => 1,
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);
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/**
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* Parse BER-encoding
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*
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* Serves a similar purpose to openssl's asn1parse
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*
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* @param string $encoded
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* @return array
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* @access public
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*/
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function decodeBER($encoded)
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{
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if ($encoded instanceof Element) {
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$encoded = $encoded->element;
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}
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$this->encoded = $encoded;
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// encapsulate in an array for BC with the old decodeBER
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return array($this->_decode_ber($encoded));
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}
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/**
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* Parse BER-encoding (Helper function)
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*
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* Sometimes we want to get the BER encoding of a particular tag. $start lets us do that without having to reencode.
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* $encoded is passed by reference for the recursive calls done for self::TYPE_BIT_STRING and
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* self::TYPE_OCTET_STRING. In those cases, the indefinite length is used.
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*
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* @param string $encoded
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* @param int $start
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* @param int $encoded_pos
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* @return array
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* @access private
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*/
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function _decode_ber($encoded, $start = 0, $encoded_pos = 0)
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{
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$current = array('start' => $start);
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$type = ord($encoded[$encoded_pos++]);
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$start++;
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$constructed = ($type >> 5) & 1;
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$tag = $type & 0x1F;
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if ($tag == 0x1F) {
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$tag = 0;
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// process septets (since the eighth bit is ignored, it's not an octet)
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do {
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$loop = ord($encoded[0]) >> 7;
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$tag <<= 7;
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$tag |= ord($encoded[$encoded_pos++]) & 0x7F;
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$start++;
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} while ($loop);
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}
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// Length, as discussed in paragraph 8.1.3 of X.690-0207.pdf#page=13
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$length = ord($encoded[$encoded_pos++]);
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$start++;
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if ($length == 0x80) { // indefinite length
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// "[A sender shall] use the indefinite form (see 8.1.3.6) if the encoding is constructed and is not all
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// immediately available." -- paragraph 8.1.3.2.c
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$length = strlen($encoded) - $encoded_pos;
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} elseif ($length & 0x80) { // definite length, long form
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// technically, the long form of the length can be represented by up to 126 octets (bytes), but we'll only
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// support it up to four.
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$length&= 0x7F;
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$temp = substr($encoded, $encoded_pos, $length);
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$encoded_pos += $length;
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// tags of indefinte length don't really have a header length; this length includes the tag
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$current+= array('headerlength' => $length + 2);
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$start+= $length;
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extract(unpack('Nlength', substr(str_pad($temp, 4, chr(0), STR_PAD_LEFT), -4)));
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} else {
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$current+= array('headerlength' => 2);
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}
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if ($length > (strlen($encoded) - $encoded_pos)) {
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return false;
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}
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$content = substr($encoded, $encoded_pos, $length);
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$content_pos = 0;
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// at this point $length can be overwritten. it's only accurate for definite length things as is
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/* Class is UNIVERSAL, APPLICATION, PRIVATE, or CONTEXT-SPECIFIC. The UNIVERSAL class is restricted to the ASN.1
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built-in types. It defines an application-independent data type that must be distinguishable from all other
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data types. The other three classes are user defined. The APPLICATION class distinguishes data types that
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have a wide, scattered use within a particular presentation context. PRIVATE distinguishes data types within
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a particular organization or country. CONTEXT-SPECIFIC distinguishes members of a sequence or set, the
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alternatives of a CHOICE, or universally tagged set members. Only the class number appears in braces for this
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data type; the term CONTEXT-SPECIFIC does not appear.
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-- http://www.obj-sys.com/asn1tutorial/node12.html */
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$class = ($type >> 6) & 3;
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switch ($class) {
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case self::CLASS_APPLICATION:
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case self::CLASS_PRIVATE:
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case self::CLASS_CONTEXT_SPECIFIC:
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if (!$constructed) {
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return array(
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'type' => $class,
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'constant' => $tag,
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'content' => $content,
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'length' => $length + $start - $current['start']
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);
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}
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$newcontent = array();
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$remainingLength = $length;
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while ($remainingLength > 0) {
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$temp = $this->_decode_ber($content, $start, $content_pos);
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$length = $temp['length'];
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// end-of-content octets - see paragraph 8.1.5
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if (substr($content, $content_pos + $length, 2) == "\0\0") {
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$length+= 2;
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$start+= $length;
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$newcontent[] = $temp;
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break;
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}
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$start+= $length;
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$remainingLength-= $length;
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$newcontent[] = $temp;
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$content_pos += $length;
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}
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return array(
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'type' => $class,
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'constant' => $tag,
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// the array encapsulation is for BC with the old format
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'content' => $newcontent,
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// the only time when $content['headerlength'] isn't defined is when the length is indefinite.
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// the absence of $content['headerlength'] is how we know if something is indefinite or not.
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// technically, it could be defined to be 2 and then another indicator could be used but whatever.
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'length' => $start - $current['start']
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) + $current;
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}
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$current+= array('type' => $tag);
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// decode UNIVERSAL tags
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switch ($tag) {
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case self::TYPE_BOOLEAN:
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// "The contents octets shall consist of a single octet." -- paragraph 8.2.1
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//if (strlen($content) != 1) {
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// return false;
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//}
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$current['content'] = (bool) ord($content[$content_pos]);
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break;
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case self::TYPE_INTEGER:
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case self::TYPE_ENUMERATED:
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$current['content'] = new BigInteger(substr($content, $content_pos), -256);
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break;
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case self::TYPE_REAL: // not currently supported
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return false;
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case self::TYPE_BIT_STRING:
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// The initial octet shall encode, as an unsigned binary integer with bit 1 as the least significant bit,
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// the number of unused bits in the final subsequent octet. The number shall be in the range zero to
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// seven.
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if (!$constructed) {
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$current['content'] = substr($content, $content_pos);
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} else {
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$temp = $this->_decode_ber($content, $start, $content_pos);
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$length-= (strlen($content) - $content_pos);
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$last = count($temp) - 1;
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for ($i = 0; $i < $last; $i++) {
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// all subtags should be bit strings
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//if ($temp[$i]['type'] != self::TYPE_BIT_STRING) {
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// return false;
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//}
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$current['content'].= substr($temp[$i]['content'], 1);
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}
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// all subtags should be bit strings
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//if ($temp[$last]['type'] != self::TYPE_BIT_STRING) {
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// return false;
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//}
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$current['content'] = $temp[$last]['content'][0] . $current['content'] . substr($temp[$i]['content'], 1);
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}
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break;
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case self::TYPE_OCTET_STRING:
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if (!$constructed) {
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$current['content'] = substr($content, $content_pos);
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} else {
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$current['content'] = '';
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$length = 0;
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while (substr($content, $content_pos, 2) != "\0\0") {
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$temp = $this->_decode_ber($content, $length + $start, $content_pos);
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$content_pos += $temp['length'];
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// all subtags should be octet strings
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//if ($temp['type'] != self::TYPE_OCTET_STRING) {
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// return false;
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//}
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$current['content'].= $temp['content'];
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$length+= $temp['length'];
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}
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if (substr($content, $content_pos, 2) == "\0\0") {
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$length+= 2; // +2 for the EOC
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}
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}
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break;
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case self::TYPE_NULL:
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// "The contents octets shall not contain any octets." -- paragraph 8.8.2
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//if (strlen($content)) {
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// return false;
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//}
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break;
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case self::TYPE_SEQUENCE:
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case self::TYPE_SET:
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$offset = 0;
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$current['content'] = array();
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$content_len = strlen($content);
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while ($content_pos < $content_len) {
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// if indefinite length construction was used and we have an end-of-content string next
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// see paragraphs 8.1.1.3, 8.1.3.2, 8.1.3.6, 8.1.5, and (for an example) 8.6.4.2
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if (!isset($current['headerlength']) && substr($content, $content_pos, 2) == "\0\0") {
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$length = $offset + 2; // +2 for the EOC
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break 2;
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}
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$temp = $this->_decode_ber($content, $start + $offset, $content_pos);
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$content_pos += $temp['length'];
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$current['content'][] = $temp;
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$offset+= $temp['length'];
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}
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break;
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case self::TYPE_OBJECT_IDENTIFIER:
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$temp = ord($content[$content_pos++]);
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$current['content'] = sprintf('%d.%d', floor($temp / 40), $temp % 40);
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$valuen = 0;
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// process septets
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$content_len = strlen($content);
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while ($content_pos < $content_len) {
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$temp = ord($content[$content_pos++]);
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$valuen <<= 7;
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$valuen |= $temp & 0x7F;
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if (~$temp & 0x80) {
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$current['content'].= ".$valuen";
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$valuen = 0;
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}
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}
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// the eighth bit of the last byte should not be 1
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//if ($temp >> 7) {
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// return false;
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//}
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break;
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/* Each character string type shall be encoded as if it had been declared:
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[UNIVERSAL x] IMPLICIT OCTET STRING
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|
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-- X.690-0207.pdf#page=23 (paragraph 8.21.3)
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Per that, we're not going to do any validation. If there are any illegal characters in the string,
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we don't really care */
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case self::TYPE_NUMERIC_STRING:
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// 0,1,2,3,4,5,6,7,8,9, and space
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case self::TYPE_PRINTABLE_STRING:
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// Upper and lower case letters, digits, space, apostrophe, left/right parenthesis, plus sign, comma,
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// hyphen, full stop, solidus, colon, equal sign, question mark
|
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case self::TYPE_TELETEX_STRING:
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// The Teletex character set in CCITT's T61, space, and delete
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// see http://en.wikipedia.org/wiki/Teletex#Character_sets
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case self::TYPE_VIDEOTEX_STRING:
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// The Videotex character set in CCITT's T.100 and T.101, space, and delete
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case self::TYPE_VISIBLE_STRING:
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// Printing character sets of international ASCII, and space
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case self::TYPE_IA5_STRING:
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// International Alphabet 5 (International ASCII)
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case self::TYPE_GRAPHIC_STRING:
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// All registered G sets, and space
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case self::TYPE_GENERAL_STRING:
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// All registered C and G sets, space and delete
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case self::TYPE_UTF8_STRING:
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// ????
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case self::TYPE_BMP_STRING:
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$current['content'] = substr($content, $content_pos);
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break;
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case self::TYPE_UTC_TIME:
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case self::TYPE_GENERALIZED_TIME:
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$current['content'] = $this->_decodeTime(substr($content, $content_pos), $tag);
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default:
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}
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|
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$start+= $length;
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// ie. length is the length of the full TLV encoding - it's not just the length of the value
|
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return $current + array('length' => $start - $current['start']);
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}
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|
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/**
|
|
* ASN.1 Map
|
|
*
|
|
* Provides an ASN.1 semantic mapping ($mapping) from a parsed BER-encoding to a human readable format.
|
|
*
|
|
* "Special" mappings may be applied on a per tag-name basis via $special.
|
|
*
|
|
* @param array $decoded
|
|
* @param array $mapping
|
|
* @param array $special
|
|
* @return array
|
|
* @access public
|
|
*/
|
|
function asn1map($decoded, $mapping, $special = array())
|
|
{
|
|
if (isset($mapping['explicit']) && is_array($decoded['content'])) {
|
|
$decoded = $decoded['content'][0];
|
|
}
|
|
|
|
switch (true) {
|
|
case $mapping['type'] == self::TYPE_ANY:
|
|
$intype = $decoded['type'];
|
|
if (isset($decoded['constant']) || !isset($this->ANYmap[$intype]) || (ord($this->encoded[$decoded['start']]) & 0x20)) {
|
|
return new Element(substr($this->encoded, $decoded['start'], $decoded['length']));
|
|
}
|
|
$inmap = $this->ANYmap[$intype];
|
|
if (is_string($inmap)) {
|
|
return array($inmap => $this->asn1map($decoded, array('type' => $intype) + $mapping, $special));
|
|
}
|
|
break;
|
|
case $mapping['type'] == self::TYPE_CHOICE:
|
|
foreach ($mapping['children'] as $key => $option) {
|
|
switch (true) {
|
|
case isset($option['constant']) && $option['constant'] == $decoded['constant']:
|
|
case !isset($option['constant']) && $option['type'] == $decoded['type']:
|
|
$value = $this->asn1map($decoded, $option, $special);
|
|
break;
|
|
case !isset($option['constant']) && $option['type'] == self::TYPE_CHOICE:
|
|
$v = $this->asn1map($decoded, $option, $special);
|
|
if (isset($v)) {
|
|
$value = $v;
|
|
}
|
|
}
|
|
if (isset($value)) {
|
|
if (isset($special[$key])) {
|
|
$value = call_user_func($special[$key], $value);
|
|
}
|
|
return array($key => $value);
|
|
}
|
|
}
|
|
return null;
|
|
case isset($mapping['implicit']):
|
|
case isset($mapping['explicit']):
|
|
case $decoded['type'] == $mapping['type']:
|
|
break;
|
|
default:
|
|
// if $decoded['type'] and $mapping['type'] are both strings, but different types of strings,
|
|
// let it through
|
|
switch (true) {
|
|
case $decoded['type'] < 18: // self::TYPE_NUMERIC_STRING == 18
|
|
case $decoded['type'] > 30: // self::TYPE_BMP_STRING == 30
|
|
case $mapping['type'] < 18:
|
|
case $mapping['type'] > 30:
|
|
return null;
|
|
}
|
|
}
|
|
|
|
if (isset($mapping['implicit'])) {
|
|
$decoded['type'] = $mapping['type'];
|
|
}
|
|
|
|
switch ($decoded['type']) {
|
|
case self::TYPE_SEQUENCE:
|
|
$map = array();
|
|
|
|
// ignore the min and max
|
|
if (isset($mapping['min']) && isset($mapping['max'])) {
|
|
$child = $mapping['children'];
|
|
foreach ($decoded['content'] as $content) {
|
|
if (($map[] = $this->asn1map($content, $child, $special)) === null) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
return $map;
|
|
}
|
|
|
|
$n = count($decoded['content']);
|
|
$i = 0;
|
|
|
|
foreach ($mapping['children'] as $key => $child) {
|
|
$maymatch = $i < $n; // Match only existing input.
|
|
if ($maymatch) {
|
|
$temp = $decoded['content'][$i];
|
|
|
|
if ($child['type'] != self::TYPE_CHOICE) {
|
|
// Get the mapping and input class & constant.
|
|
$childClass = $tempClass = self::CLASS_UNIVERSAL;
|
|
$constant = null;
|
|
if (isset($temp['constant'])) {
|
|
$tempClass = isset($temp['class']) ? $temp['class'] : self::CLASS_CONTEXT_SPECIFIC;
|
|
}
|
|
if (isset($child['class'])) {
|
|
$childClass = $child['class'];
|
|
$constant = $child['cast'];
|
|
} elseif (isset($child['constant'])) {
|
|
$childClass = self::CLASS_CONTEXT_SPECIFIC;
|
|
$constant = $child['constant'];
|
|
}
|
|
|
|
if (isset($constant) && isset($temp['constant'])) {
|
|
// Can only match if constants and class match.
|
|
$maymatch = $constant == $temp['constant'] && $childClass == $tempClass;
|
|
} else {
|
|
// Can only match if no constant expected and type matches or is generic.
|
|
$maymatch = !isset($child['constant']) && array_search($child['type'], array($temp['type'], self::TYPE_ANY, self::TYPE_CHOICE)) !== false;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ($maymatch) {
|
|
// Attempt submapping.
|
|
$candidate = $this->asn1map($temp, $child, $special);
|
|
$maymatch = $candidate !== null;
|
|
}
|
|
|
|
if ($maymatch) {
|
|
// Got the match: use it.
|
|
if (isset($special[$key])) {
|
|
$candidate = call_user_func($special[$key], $candidate);
|
|
}
|
|
$map[$key] = $candidate;
|
|
$i++;
|
|
} elseif (isset($child['default'])) {
|
|
$map[$key] = $child['default']; // Use default.
|
|
} elseif (!isset($child['optional'])) {
|
|
return null; // Syntax error.
|
|
}
|
|
}
|
|
|
|
// Fail mapping if all input items have not been consumed.
|
|
return $i < $n ? null: $map;
|
|
|
|
// the main diff between sets and sequences is the encapsulation of the foreach in another for loop
|
|
case self::TYPE_SET:
|
|
$map = array();
|
|
|
|
// ignore the min and max
|
|
if (isset($mapping['min']) && isset($mapping['max'])) {
|
|
$child = $mapping['children'];
|
|
foreach ($decoded['content'] as $content) {
|
|
if (($map[] = $this->asn1map($content, $child, $special)) === null) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
return $map;
|
|
}
|
|
|
|
for ($i = 0; $i < count($decoded['content']); $i++) {
|
|
$temp = $decoded['content'][$i];
|
|
$tempClass = self::CLASS_UNIVERSAL;
|
|
if (isset($temp['constant'])) {
|
|
$tempClass = isset($temp['class']) ? $temp['class'] : self::CLASS_CONTEXT_SPECIFIC;
|
|
}
|
|
|
|
foreach ($mapping['children'] as $key => $child) {
|
|
if (isset($map[$key])) {
|
|
continue;
|
|
}
|
|
$maymatch = true;
|
|
if ($child['type'] != self::TYPE_CHOICE) {
|
|
$childClass = self::CLASS_UNIVERSAL;
|
|
$constant = null;
|
|
if (isset($child['class'])) {
|
|
$childClass = $child['class'];
|
|
$constant = $child['cast'];
|
|
} elseif (isset($child['constant'])) {
|
|
$childClass = self::CLASS_CONTEXT_SPECIFIC;
|
|
$constant = $child['constant'];
|
|
}
|
|
|
|
if (isset($constant) && isset($temp['constant'])) {
|
|
// Can only match if constants and class match.
|
|
$maymatch = $constant == $temp['constant'] && $childClass == $tempClass;
|
|
} else {
|
|
// Can only match if no constant expected and type matches or is generic.
|
|
$maymatch = !isset($child['constant']) && array_search($child['type'], array($temp['type'], self::TYPE_ANY, self::TYPE_CHOICE)) !== false;
|
|
}
|
|
}
|
|
|
|
if ($maymatch) {
|
|
// Attempt submapping.
|
|
$candidate = $this->asn1map($temp, $child, $special);
|
|
$maymatch = $candidate !== null;
|
|
}
|
|
|
|
if (!$maymatch) {
|
|
break;
|
|
}
|
|
|
|
// Got the match: use it.
|
|
if (isset($special[$key])) {
|
|
$candidate = call_user_func($special[$key], $candidate);
|
|
}
|
|
$map[$key] = $candidate;
|
|
break;
|
|
}
|
|
}
|
|
|
|
foreach ($mapping['children'] as $key => $child) {
|
|
if (!isset($map[$key])) {
|
|
if (isset($child['default'])) {
|
|
$map[$key] = $child['default'];
|
|
} elseif (!isset($child['optional'])) {
|
|
return null;
|
|
}
|
|
}
|
|
}
|
|
return $map;
|
|
case self::TYPE_OBJECT_IDENTIFIER:
|
|
return isset($this->oids[$decoded['content']]) ? $this->oids[$decoded['content']] : $decoded['content'];
|
|
case self::TYPE_UTC_TIME:
|
|
case self::TYPE_GENERALIZED_TIME:
|
|
if (isset($mapping['implicit'])) {
|
|
$decoded['content'] = $this->_decodeTime($decoded['content'], $decoded['type']);
|
|
}
|
|
return @date($this->format, $decoded['content']);
|
|
case self::TYPE_BIT_STRING:
|
|
if (isset($mapping['mapping'])) {
|
|
$offset = ord($decoded['content'][0]);
|
|
$size = (strlen($decoded['content']) - 1) * 8 - $offset;
|
|
/*
|
|
From X.680-0207.pdf#page=46 (21.7):
|
|
|
|
"When a "NamedBitList" is used in defining a bitstring type ASN.1 encoding rules are free to add (or remove)
|
|
arbitrarily any trailing 0 bits to (or from) values that are being encoded or decoded. Application designers should
|
|
therefore ensure that different semantics are not associated with such values which differ only in the number of trailing
|
|
0 bits."
|
|
*/
|
|
$bits = count($mapping['mapping']) == $size ? array() : array_fill(0, count($mapping['mapping']) - $size, false);
|
|
for ($i = strlen($decoded['content']) - 1; $i > 0; $i--) {
|
|
$current = ord($decoded['content'][$i]);
|
|
for ($j = $offset; $j < 8; $j++) {
|
|
$bits[] = (bool) ($current & (1 << $j));
|
|
}
|
|
$offset = 0;
|
|
}
|
|
$values = array();
|
|
$map = array_reverse($mapping['mapping']);
|
|
foreach ($map as $i => $value) {
|
|
if ($bits[$i]) {
|
|
$values[] = $value;
|
|
}
|
|
}
|
|
return $values;
|
|
}
|
|
case self::TYPE_OCTET_STRING:
|
|
return base64_encode($decoded['content']);
|
|
case self::TYPE_NULL:
|
|
return '';
|
|
case self::TYPE_BOOLEAN:
|
|
return $decoded['content'];
|
|
case self::TYPE_NUMERIC_STRING:
|
|
case self::TYPE_PRINTABLE_STRING:
|
|
case self::TYPE_TELETEX_STRING:
|
|
case self::TYPE_VIDEOTEX_STRING:
|
|
case self::TYPE_IA5_STRING:
|
|
case self::TYPE_GRAPHIC_STRING:
|
|
case self::TYPE_VISIBLE_STRING:
|
|
case self::TYPE_GENERAL_STRING:
|
|
case self::TYPE_UNIVERSAL_STRING:
|
|
case self::TYPE_UTF8_STRING:
|
|
case self::TYPE_BMP_STRING:
|
|
return $decoded['content'];
|
|
case self::TYPE_INTEGER:
|
|
case self::TYPE_ENUMERATED:
|
|
$temp = $decoded['content'];
|
|
if (isset($mapping['implicit'])) {
|
|
$temp = new BigInteger($decoded['content'], -256);
|
|
}
|
|
if (isset($mapping['mapping'])) {
|
|
$temp = (int) $temp->toString();
|
|
return isset($mapping['mapping'][$temp]) ?
|
|
$mapping['mapping'][$temp] :
|
|
false;
|
|
}
|
|
return $temp;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* ASN.1 Encode
|
|
*
|
|
* DER-encodes an ASN.1 semantic mapping ($mapping). Some libraries would probably call this function
|
|
* an ASN.1 compiler.
|
|
*
|
|
* "Special" mappings can be applied via $special.
|
|
*
|
|
* @param string $source
|
|
* @param string $mapping
|
|
* @param int $idx
|
|
* @return string
|
|
* @access public
|
|
*/
|
|
function encodeDER($source, $mapping, $special = array())
|
|
{
|
|
$this->location = array();
|
|
return $this->_encode_der($source, $mapping, null, $special);
|
|
}
|
|
|
|
/**
|
|
* ASN.1 Encode (Helper function)
|
|
*
|
|
* @param string $source
|
|
* @param string $mapping
|
|
* @param int $idx
|
|
* @return string
|
|
* @access private
|
|
*/
|
|
function _encode_der($source, $mapping, $idx = null, $special = array())
|
|
{
|
|
if ($source instanceof Element) {
|
|
return $source->element;
|
|
}
|
|
|
|
// do not encode (implicitly optional) fields with value set to default
|
|
if (isset($mapping['default']) && $source === $mapping['default']) {
|
|
return '';
|
|
}
|
|
|
|
if (isset($idx)) {
|
|
if (isset($special[$idx])) {
|
|
$source = call_user_func($special[$idx], $source);
|
|
}
|
|
$this->location[] = $idx;
|
|
}
|
|
|
|
$tag = $mapping['type'];
|
|
|
|
switch ($tag) {
|
|
case self::TYPE_SET: // Children order is not important, thus process in sequence.
|
|
case self::TYPE_SEQUENCE:
|
|
$tag|= 0x20; // set the constructed bit
|
|
|
|
// ignore the min and max
|
|
if (isset($mapping['min']) && isset($mapping['max'])) {
|
|
$value = array();
|
|
$child = $mapping['children'];
|
|
|
|
foreach ($source as $content) {
|
|
$temp = $this->_encode_der($content, $child, null, $special);
|
|
if ($temp === false) {
|
|
return false;
|
|
}
|
|
$value[]= $temp;
|
|
}
|
|
/* "The encodings of the component values of a set-of value shall appear in ascending order, the encodings being compared
|
|
as octet strings with the shorter components being padded at their trailing end with 0-octets.
|
|
NOTE - The padding octets are for comparison purposes only and do not appear in the encodings."
|
|
|
|
-- sec 11.6 of http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf */
|
|
if ($mapping['type'] == self::TYPE_SET) {
|
|
sort($value);
|
|
}
|
|
$value = implode($value, '');
|
|
break;
|
|
}
|
|
|
|
$value = '';
|
|
foreach ($mapping['children'] as $key => $child) {
|
|
if (!array_key_exists($key, $source)) {
|
|
if (!isset($child['optional'])) {
|
|
return false;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
$temp = $this->_encode_der($source[$key], $child, $key, $special);
|
|
if ($temp === false) {
|
|
return false;
|
|
}
|
|
|
|
// An empty child encoding means it has been optimized out.
|
|
// Else we should have at least one tag byte.
|
|
if ($temp === '') {
|
|
continue;
|
|
}
|
|
|
|
// if isset($child['constant']) is true then isset($child['optional']) should be true as well
|
|
if (isset($child['constant'])) {
|
|
/*
|
|
From X.680-0207.pdf#page=58 (30.6):
|
|
|
|
"The tagging construction specifies explicit tagging if any of the following holds:
|
|
...
|
|
c) the "Tag Type" alternative is used and the value of "TagDefault" for the module is IMPLICIT TAGS or
|
|
AUTOMATIC TAGS, but the type defined by "Type" is an untagged choice type, an untagged open type, or
|
|
an untagged "DummyReference" (see ITU-T Rec. X.683 | ISO/IEC 8824-4, 8.3)."
|
|
*/
|
|
if (isset($child['explicit']) || $child['type'] == self::TYPE_CHOICE) {
|
|
$subtag = chr((self::CLASS_CONTEXT_SPECIFIC << 6) | 0x20 | $child['constant']);
|
|
$temp = $subtag . $this->_encodeLength(strlen($temp)) . $temp;
|
|
} else {
|
|
$subtag = chr((self::CLASS_CONTEXT_SPECIFIC << 6) | (ord($temp[0]) & 0x20) | $child['constant']);
|
|
$temp = $subtag . substr($temp, 1);
|
|
}
|
|
}
|
|
$value.= $temp;
|
|
}
|
|
break;
|
|
case self::TYPE_CHOICE:
|
|
$temp = false;
|
|
|
|
foreach ($mapping['children'] as $key => $child) {
|
|
if (!isset($source[$key])) {
|
|
continue;
|
|
}
|
|
|
|
$temp = $this->_encode_der($source[$key], $child, $key, $special);
|
|
if ($temp === false) {
|
|
return false;
|
|
}
|
|
|
|
// An empty child encoding means it has been optimized out.
|
|
// Else we should have at least one tag byte.
|
|
if ($temp === '') {
|
|
continue;
|
|
}
|
|
|
|
$tag = ord($temp[0]);
|
|
|
|
// if isset($child['constant']) is true then isset($child['optional']) should be true as well
|
|
if (isset($child['constant'])) {
|
|
if (isset($child['explicit']) || $child['type'] == self::TYPE_CHOICE) {
|
|
$subtag = chr((self::CLASS_CONTEXT_SPECIFIC << 6) | 0x20 | $child['constant']);
|
|
$temp = $subtag . $this->_encodeLength(strlen($temp)) . $temp;
|
|
} else {
|
|
$subtag = chr((self::CLASS_CONTEXT_SPECIFIC << 6) | (ord($temp[0]) & 0x20) | $child['constant']);
|
|
$temp = $subtag . substr($temp, 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (isset($idx)) {
|
|
array_pop($this->location);
|
|
}
|
|
|
|
if ($temp && isset($mapping['cast'])) {
|
|
$temp[0] = chr(($mapping['class'] << 6) | ($tag & 0x20) | $mapping['cast']);
|
|
}
|
|
|
|
return $temp;
|
|
case self::TYPE_INTEGER:
|
|
case self::TYPE_ENUMERATED:
|
|
if (!isset($mapping['mapping'])) {
|
|
if (is_numeric($source)) {
|
|
$source = new BigInteger($source);
|
|
}
|
|
$value = $source->toBytes(true);
|
|
} else {
|
|
$value = array_search($source, $mapping['mapping']);
|
|
if ($value === false) {
|
|
return false;
|
|
}
|
|
$value = new BigInteger($value);
|
|
$value = $value->toBytes(true);
|
|
}
|
|
if (!strlen($value)) {
|
|
$value = chr(0);
|
|
}
|
|
break;
|
|
case self::TYPE_UTC_TIME:
|
|
case self::TYPE_GENERALIZED_TIME:
|
|
$format = $mapping['type'] == self::TYPE_UTC_TIME ? 'y' : 'Y';
|
|
$format.= 'mdHis';
|
|
$value = @gmdate($format, strtotime($source)) . 'Z';
|
|
break;
|
|
case self::TYPE_BIT_STRING:
|
|
if (isset($mapping['mapping'])) {
|
|
$bits = array_fill(0, count($mapping['mapping']), 0);
|
|
$size = 0;
|
|
for ($i = 0; $i < count($mapping['mapping']); $i++) {
|
|
if (in_array($mapping['mapping'][$i], $source)) {
|
|
$bits[$i] = 1;
|
|
$size = $i;
|
|
}
|
|
}
|
|
|
|
if (isset($mapping['min']) && $mapping['min'] >= 1 && $size < $mapping['min']) {
|
|
$size = $mapping['min'] - 1;
|
|
}
|
|
|
|
$offset = 8 - (($size + 1) & 7);
|
|
$offset = $offset !== 8 ? $offset : 0;
|
|
|
|
$value = chr($offset);
|
|
|
|
for ($i = $size + 1; $i < count($mapping['mapping']); $i++) {
|
|
unset($bits[$i]);
|
|
}
|
|
|
|
$bits = implode('', array_pad($bits, $size + $offset + 1, 0));
|
|
$bytes = explode(' ', rtrim(chunk_split($bits, 8, ' ')));
|
|
foreach ($bytes as $byte) {
|
|
$value.= chr(bindec($byte));
|
|
}
|
|
|
|
break;
|
|
}
|
|
case self::TYPE_OCTET_STRING:
|
|
/* The initial octet shall encode, as an unsigned binary integer with bit 1 as the least significant bit,
|
|
the number of unused bits in the final subsequent octet. The number shall be in the range zero to seven.
|
|
|
|
-- http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#page=16 */
|
|
$value = base64_decode($source);
|
|
break;
|
|
case self::TYPE_OBJECT_IDENTIFIER:
|
|
$oid = preg_match('#(?:\d+\.)+#', $source) ? $source : array_search($source, $this->oids);
|
|
if ($oid === false) {
|
|
user_error('Invalid OID');
|
|
return false;
|
|
}
|
|
$value = '';
|
|
$parts = explode('.', $oid);
|
|
$value = chr(40 * $parts[0] + $parts[1]);
|
|
for ($i = 2; $i < count($parts); $i++) {
|
|
$temp = '';
|
|
if (!$parts[$i]) {
|
|
$temp = "\0";
|
|
} else {
|
|
while ($parts[$i]) {
|
|
$temp = chr(0x80 | ($parts[$i] & 0x7F)) . $temp;
|
|
$parts[$i] >>= 7;
|
|
}
|
|
$temp[strlen($temp) - 1] = $temp[strlen($temp) - 1] & chr(0x7F);
|
|
}
|
|
$value.= $temp;
|
|
}
|
|
break;
|
|
case self::TYPE_ANY:
|
|
$loc = $this->location;
|
|
if (isset($idx)) {
|
|
array_pop($this->location);
|
|
}
|
|
|
|
switch (true) {
|
|
case !isset($source):
|
|
return $this->_encode_der(null, array('type' => self::TYPE_NULL) + $mapping, null, $special);
|
|
case is_int($source):
|
|
case $source instanceof BigInteger:
|
|
return $this->_encode_der($source, array('type' => self::TYPE_INTEGER) + $mapping, null, $special);
|
|
case is_float($source):
|
|
return $this->_encode_der($source, array('type' => self::TYPE_REAL) + $mapping, null, $special);
|
|
case is_bool($source):
|
|
return $this->_encode_der($source, array('type' => self::TYPE_BOOLEAN) + $mapping, null, $special);
|
|
case is_array($source) && count($source) == 1:
|
|
$typename = implode('', array_keys($source));
|
|
$outtype = array_search($typename, $this->ANYmap, true);
|
|
if ($outtype !== false) {
|
|
return $this->_encode_der($source[$typename], array('type' => $outtype) + $mapping, null, $special);
|
|
}
|
|
}
|
|
|
|
$filters = $this->filters;
|
|
foreach ($loc as $part) {
|
|
if (!isset($filters[$part])) {
|
|
$filters = false;
|
|
break;
|
|
}
|
|
$filters = $filters[$part];
|
|
}
|
|
if ($filters === false) {
|
|
user_error('No filters defined for ' . implode('/', $loc));
|
|
return false;
|
|
}
|
|
return $this->_encode_der($source, $filters + $mapping, null, $special);
|
|
case self::TYPE_NULL:
|
|
$value = '';
|
|
break;
|
|
case self::TYPE_NUMERIC_STRING:
|
|
case self::TYPE_TELETEX_STRING:
|
|
case self::TYPE_PRINTABLE_STRING:
|
|
case self::TYPE_UNIVERSAL_STRING:
|
|
case self::TYPE_UTF8_STRING:
|
|
case self::TYPE_BMP_STRING:
|
|
case self::TYPE_IA5_STRING:
|
|
case self::TYPE_VISIBLE_STRING:
|
|
case self::TYPE_VIDEOTEX_STRING:
|
|
case self::TYPE_GRAPHIC_STRING:
|
|
case self::TYPE_GENERAL_STRING:
|
|
$value = $source;
|
|
break;
|
|
case self::TYPE_BOOLEAN:
|
|
$value = $source ? "\xFF" : "\x00";
|
|
break;
|
|
default:
|
|
user_error('Mapping provides no type definition for ' . implode('/', $this->location));
|
|
return false;
|
|
}
|
|
|
|
if (isset($idx)) {
|
|
array_pop($this->location);
|
|
}
|
|
|
|
if (isset($mapping['cast'])) {
|
|
if (isset($mapping['explicit']) || $mapping['type'] == self::TYPE_CHOICE) {
|
|
$value = chr($tag) . $this->_encodeLength(strlen($value)) . $value;
|
|
$tag = ($mapping['class'] << 6) | 0x20 | $mapping['cast'];
|
|
} else {
|
|
$tag = ($mapping['class'] << 6) | (ord($temp[0]) & 0x20) | $mapping['cast'];
|
|
}
|
|
}
|
|
|
|
return chr($tag) . $this->_encodeLength(strlen($value)) . $value;
|
|
}
|
|
|
|
/**
|
|
* DER-encode the length
|
|
*
|
|
* DER supports lengths up to (2**8)**127, however, we'll only support lengths up to (2**8)**4. See
|
|
* {@link http://itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#p=13 X.690 paragraph 8.1.3} for more information.
|
|
*
|
|
* @access private
|
|
* @param int $length
|
|
* @return string
|
|
*/
|
|
function _encodeLength($length)
|
|
{
|
|
if ($length <= 0x7F) {
|
|
return chr($length);
|
|
}
|
|
|
|
$temp = ltrim(pack('N', $length), chr(0));
|
|
return pack('Ca*', 0x80 | strlen($temp), $temp);
|
|
}
|
|
|
|
/**
|
|
* BER-decode the time
|
|
*
|
|
* Called by _decode_ber() and in the case of implicit tags asn1map().
|
|
*
|
|
* @access private
|
|
* @param string $content
|
|
* @param int $tag
|
|
* @return string
|
|
*/
|
|
function _decodeTime($content, $tag)
|
|
{
|
|
/* UTCTime:
|
|
http://tools.ietf.org/html/rfc5280#section-4.1.2.5.1
|
|
http://www.obj-sys.com/asn1tutorial/node15.html
|
|
|
|
GeneralizedTime:
|
|
http://tools.ietf.org/html/rfc5280#section-4.1.2.5.2
|
|
http://www.obj-sys.com/asn1tutorial/node14.html */
|
|
|
|
$pattern = $tag == self::TYPE_UTC_TIME ?
|
|
'#(..)(..)(..)(..)(..)(..)(.*)#' :
|
|
'#(....)(..)(..)(..)(..)(..).*([Z+-].*)$#';
|
|
|
|
preg_match($pattern, $content, $matches);
|
|
|
|
list(, $year, $month, $day, $hour, $minute, $second, $timezone) = $matches;
|
|
|
|
if ($tag == self::TYPE_UTC_TIME) {
|
|
$year = $year >= 50 ? "19$year" : "20$year";
|
|
}
|
|
|
|
if ($timezone == 'Z') {
|
|
$mktime = 'gmmktime';
|
|
$timezone = 0;
|
|
} elseif (preg_match('#([+-])(\d\d)(\d\d)#', $timezone, $matches)) {
|
|
$mktime = 'gmmktime';
|
|
$timezone = 60 * $matches[3] + 3600 * $matches[2];
|
|
if ($matches[1] == '-') {
|
|
$timezone = -$timezone;
|
|
}
|
|
} else {
|
|
$mktime = 'mktime';
|
|
$timezone = 0;
|
|
}
|
|
|
|
return @$mktime($hour, $minute, $second, $month, $day, $year) + $timezone;
|
|
}
|
|
|
|
/**
|
|
* Set the time format
|
|
*
|
|
* Sets the time / date format for asn1map().
|
|
*
|
|
* @access public
|
|
* @param string $format
|
|
*/
|
|
function setTimeFormat($format)
|
|
{
|
|
$this->format = $format;
|
|
}
|
|
|
|
/**
|
|
* Load OIDs
|
|
*
|
|
* Load the relevant OIDs for a particular ASN.1 semantic mapping.
|
|
*
|
|
* @access public
|
|
* @param array $oids
|
|
*/
|
|
function loadOIDs($oids)
|
|
{
|
|
$this->oids = $oids;
|
|
}
|
|
|
|
/**
|
|
* Load filters
|
|
*
|
|
* See \phpseclib\File\X509, etc, for an example.
|
|
*
|
|
* @access public
|
|
* @param array $filters
|
|
*/
|
|
function loadFilters($filters)
|
|
{
|
|
$this->filters = $filters;
|
|
}
|
|
|
|
/**
|
|
* String Shift
|
|
*
|
|
* Inspired by array_shift
|
|
*
|
|
* @param string $string
|
|
* @param int $index
|
|
* @return string
|
|
* @access private
|
|
*/
|
|
function _string_shift(&$string, $index = 1)
|
|
{
|
|
$substr = substr($string, 0, $index);
|
|
$string = substr($string, $index);
|
|
return $substr;
|
|
}
|
|
|
|
/**
|
|
* String type conversion
|
|
*
|
|
* This is a lazy conversion, dealing only with character size.
|
|
* No real conversion table is used.
|
|
*
|
|
* @param string $in
|
|
* @param int $from
|
|
* @param int $to
|
|
* @return string
|
|
* @access public
|
|
*/
|
|
function convert($in, $from = self::TYPE_UTF8_STRING, $to = self::TYPE_UTF8_STRING)
|
|
{
|
|
if (!isset($this->stringTypeSize[$from]) || !isset($this->stringTypeSize[$to])) {
|
|
return false;
|
|
}
|
|
$insize = $this->stringTypeSize[$from];
|
|
$outsize = $this->stringTypeSize[$to];
|
|
$inlength = strlen($in);
|
|
$out = '';
|
|
|
|
for ($i = 0; $i < $inlength;) {
|
|
if ($inlength - $i < $insize) {
|
|
return false;
|
|
}
|
|
|
|
// Get an input character as a 32-bit value.
|
|
$c = ord($in[$i++]);
|
|
switch (true) {
|
|
case $insize == 4:
|
|
$c = ($c << 8) | ord($in[$i++]);
|
|
$c = ($c << 8) | ord($in[$i++]);
|
|
case $insize == 2:
|
|
$c = ($c << 8) | ord($in[$i++]);
|
|
case $insize == 1:
|
|
break;
|
|
case ($c & 0x80) == 0x00:
|
|
break;
|
|
case ($c & 0x40) == 0x00:
|
|
return false;
|
|
default:
|
|
$bit = 6;
|
|
do {
|
|
if ($bit > 25 || $i >= $inlength || (ord($in[$i]) & 0xC0) != 0x80) {
|
|
return false;
|
|
}
|
|
$c = ($c << 6) | (ord($in[$i++]) & 0x3F);
|
|
$bit += 5;
|
|
$mask = 1 << $bit;
|
|
} while ($c & $bit);
|
|
$c &= $mask - 1;
|
|
break;
|
|
}
|
|
|
|
// Convert and append the character to output string.
|
|
$v = '';
|
|
switch (true) {
|
|
case $outsize == 4:
|
|
$v .= chr($c & 0xFF);
|
|
$c >>= 8;
|
|
$v .= chr($c & 0xFF);
|
|
$c >>= 8;
|
|
case $outsize == 2:
|
|
$v .= chr($c & 0xFF);
|
|
$c >>= 8;
|
|
case $outsize == 1:
|
|
$v .= chr($c & 0xFF);
|
|
$c >>= 8;
|
|
if ($c) {
|
|
return false;
|
|
}
|
|
break;
|
|
case ($c & 0x80000000) != 0:
|
|
return false;
|
|
case $c >= 0x04000000:
|
|
$v .= chr(0x80 | ($c & 0x3F));
|
|
$c = ($c >> 6) | 0x04000000;
|
|
case $c >= 0x00200000:
|
|
$v .= chr(0x80 | ($c & 0x3F));
|
|
$c = ($c >> 6) | 0x00200000;
|
|
case $c >= 0x00010000:
|
|
$v .= chr(0x80 | ($c & 0x3F));
|
|
$c = ($c >> 6) | 0x00010000;
|
|
case $c >= 0x00000800:
|
|
$v .= chr(0x80 | ($c & 0x3F));
|
|
$c = ($c >> 6) | 0x00000800;
|
|
case $c >= 0x00000080:
|
|
$v .= chr(0x80 | ($c & 0x3F));
|
|
$c = ($c >> 6) | 0x000000C0;
|
|
default:
|
|
$v .= chr($c);
|
|
break;
|
|
}
|
|
$out .= strrev($v);
|
|
}
|
|
return $out;
|
|
}
|
|
}
|