DNParser::_skipWs() - Code Metrics - sop/x501 - Measure and Improve Code Quality continuously with Scrutinizer

DNParser::_skipWs() A
last analyzed 2019-06-28 10:37 UTC

↳ Parent: DNParser

Complexity

Conditions	3
Paths	3

Size

Total Lines	10
Code Lines	6

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	7
CRAP Score	3

Importance

Changes

Metric	Value
eloc	6
dl	0
loc	10
ccs	7
cts	7
cp	1
rs	10
c	0
b	0
f	0
cc	3
nc	3
nop	1
crap	3

<?php

declare(strict_types = 1);

namespace Sop\X501\DN;

use Sop\ASN1\Element;
use Sop\ASN1\Exception\DecodeException;

/**
 * Distinguished Name parsing conforming to RFC 2253 and RFC 1779.
 *
 * @see https://tools.ietf.org/html/rfc1779
 * @see https://tools.ietf.org/html/rfc2253
 */
class DNParser
{
    /**
     * RFC 2253 special characters.
     *
     * @var string
     */
    const SPECIAL_CHARS = ',=+<>#;';

    /**
     * DN string.
     *
     * @var string
     */
    private $_dn;

    /**
     * DN string length.
     *
     * @var int
     */
    private $_len;

    /**
     * Constructor.
     *
     * @param string $dn Distinguised name
     */
    protected function __construct(string $dn)
    {
        $this->_dn = $dn;
        $this->_len = strlen($dn);
    }

    /**
     * Parse distinguished name string to name-components.
     *
     * @param string $dn
     *
     * @return array
     */
    public static function parseString(string $dn): array
    {
        $parser = new self($dn);
        return $parser->parse();
    }

    /**
     * Escape a AttributeValue string conforming to RFC 2253.
     *
     * @see https://tools.ietf.org/html/rfc2253#section-2.4
     *
     * @param string $str
     *
     * @return string
     */
    public static function escapeString(string $str): string
    {
        // one of the characters ",", "+", """, "\", "<", ">" or ";"
        $str = preg_replace('/([,\+"\\\<\>;])/u', '\\\\$1', $str);
        // a space character occurring at the end of the string
        $str = preg_replace('/( )$/u', '\\\\$1', $str);
        // a space or "#" character occurring at the beginning of the string
        $str = preg_replace('/^([ #])/u', '\\\\$1', $str);
        // implementation specific special characters
        $str = preg_replace_callback('/([\pC])/u',
            function ($m) {
                $octets = str_split(bin2hex($m[1]), 2);
                return implode('',
                    array_map(
                        function ($octet) {
                            return '\\' . strtoupper($octet);
                        }, $octets));
            }, $str);
        return $str;
    }

    /**
     * Parse DN to name-components.
     *
     * @throws \RuntimeException
     *
     * @return array
     */
    protected function parse(): array
    {
        $offset = 0;
        $name = $this->_parseName($offset);
        if ($offset < $this->_len) {
            $remains = substr($this->_dn, $offset);
            throw new \UnexpectedValueException(sprintf(
                'Parser finished before the end of string, remaining: %s',
                $remains));
        }
        return $name;
    }

    /**
     * Parse 'name'.
     *
     * name-component *("," name-component)
     *
     * @param int $offset
     *
     * @return array Array of name-components
     */
    private function _parseName(int &$offset): array
    {
        $idx = $offset;
        $names = [];
        while ($idx < $this->_len) {
            $names[] = $this->_parseNameComponent($idx);
            if ($idx >= $this->_len) {
                break;
            }
            $this->_skipWs($idx);
            if (',' != $this->_dn[$idx] && ';' != $this->_dn[$idx]) {
                break;
            }
            ++$idx;
            $this->_skipWs($idx);
        }
        $offset = $idx;
        return array_reverse($names);
    }

    /**
     * Parse 'name-component'.
     *
     * attributeTypeAndValue *("+" attributeTypeAndValue)
     *
     * @param int $offset
     *
     * @return array Array of [type, value] tuples
     */
    private function _parseNameComponent(int &$offset): array
    {
        $idx = $offset;
        $tvpairs = [];
        while ($idx < $this->_len) {
            $tvpairs[] = $this->_parseAttrTypeAndValue($idx);
            $this->_skipWs($idx);
            if ($idx >= $this->_len || '+' != $this->_dn[$idx]) {
                break;
            }
            ++$idx;
            $this->_skipWs($idx);
        }
        $offset = $idx;
        return $tvpairs;
    }

    /**
     * Parse 'attributeTypeAndValue'.
     *
     * attributeType "=" attributeValue
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return array A tuple of [type, value]. Value may be either a string or
     *               an Element, if it's encoded as hexstring.
     */
    private function _parseAttrTypeAndValue(int &$offset): array
    {
        $idx = $offset;
        $type = $this->_parseAttrType($idx);
        $this->_skipWs($idx);
        if ($idx >= $this->_len || '=' != $this->_dn[$idx++]) {
            throw new \UnexpectedValueException('Invalid type and value pair.');
        }
        $this->_skipWs($idx);
        // hexstring
        if ($idx < $this->_len && '#' == $this->_dn[$idx]) {
            ++$idx;
            $data = $this->_parseAttrHexValue($idx);
            try {
                $value = Element::fromDER($data);
            } catch (DecodeException $e) {
                throw new \UnexpectedValueException(
                    'Invalid DER encoding from hexstring.', 0, $e);
            }
        } else {
            $value = $this->_parseAttrStringValue($idx);
        }
        $offset = $idx;
        return [$type, $value];
    }

    /**
     * Parse 'attributeType'.
     *
     * (ALPHA 1*keychar) / oid
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parseAttrType(int &$offset): string
    {
        $idx = $offset;
        // dotted OID
        $type = $this->_regexMatch('/^(?:oid\.)?([0-9]+(?:\.[0-9]+)*)/i', $idx);
        if (null === $type) {
            // name
            $type = $this->_regexMatch('/^[a-z][a-z0-9\-]*/i', $idx);
            if (null === $type) {
                throw new \UnexpectedValueException('Invalid attribute type.');
            }
        }
        $offset = $idx;
        return $type;
    }

    /**
     * Parse 'attributeValue' of string type.
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parseAttrStringValue(int &$offset): string
    {
        $idx = $offset;
        if ($idx >= $this->_len) {
            return '';
        }
        if ('"' == $this->_dn[$idx]) { // quoted string
            $val = $this->_parseQuotedAttrString($idx);
        } else { // string
            $val = $this->_parseAttrString($idx);
        }
        $offset = $idx;
        return $val;
    }

    /**
     * Parse plain 'attributeValue' string.
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parseAttrString(int &$offset): string
    {
        $idx = $offset;
        $val = '';
        $wsidx = null;
        while ($idx < $this->_len) {
            $c = $this->_dn[$idx];
            // pair (escape sequence)
            if ('\\' == $c) {
                ++$idx;
                $val .= $this->_parsePairAfterSlash($idx);
                $wsidx = null;
                continue;
            }
            if ('"' == $c) {
                throw new \UnexpectedValueException('Unexpected quotation.');
            }
            if (false !== strpos(self::SPECIAL_CHARS, $c)) {
                break;
            }
            // keep track of the first consecutive whitespace
            if (' ' == $c) {
                if (null === $wsidx) {
                    $wsidx = $idx;
                }
            } else {
                $wsidx = null;
            }
            // stringchar
            $val .= $c;
            ++$idx;
        }
        // if there was non-escaped whitespace in the end of the value
        if (null !== $wsidx) {
            $val = substr($val, 0, -($idx - $wsidx));
        }
        $offset = $idx;
        return $val;
    }

    /**
     * Parse quoted 'attributeValue' string.
     *
     * @param int $offset Offset to starting quote
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parseQuotedAttrString(int &$offset): string
    {
        $idx = $offset + 1;
        $val = '';
        while ($idx < $this->_len) {
            $c = $this->_dn[$idx];
            if ('\\' == $c) { // pair
                ++$idx;
                $val .= $this->_parsePairAfterSlash($idx);
                continue;
            }
            if ('"' == $c) {
                ++$idx;
                break;
            }
            $val .= $c;
            ++$idx;
        }
        $offset = $idx;
        return $val;
    }

    /**
     * Parse 'attributeValue' of binary type.
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parseAttrHexValue(int &$offset): string
    {
        $idx = $offset;
        $hexstr = $this->_regexMatch('/^(?:[0-9a-f]{2})+/i', $idx);
        if (null === $hexstr) {
            throw new \UnexpectedValueException('Invalid hexstring.');
        }
        $data = hex2bin($hexstr);
        $offset = $idx;
        return $data;
    }

    /**
     * Parse 'pair' after leading slash.
     *
     * @param int $offset
     *
     * @throws \UnexpectedValueException
     *
     * @return string
     */
    private function _parsePairAfterSlash(int &$offset): string
    {
        $idx = $offset;
        if ($idx >= $this->_len) {
            throw new \UnexpectedValueException(
                'Unexpected end of escape sequence.');
        }
        $c = $this->_dn[$idx++];
        // special | \ | " | SPACE
        if (false !== strpos(self::SPECIAL_CHARS . '\\" ', $c)) {
            $val = $c;
        } else { // hexpair
            if ($idx >= $this->_len) {
                throw new \UnexpectedValueException('Unexpected end of hexpair.');
            }
            $val = @hex2bin($c . $this->_dn[$idx++]);
            if (false === $val) {
                throw new \UnexpectedValueException('Invalid hexpair.');
            }
        }
        $offset = $idx;
        return $val;
    }

    /**
     * Match DN to pattern and extract the last capture group.
     *
     * Updates offset to fully matched pattern.
     *
     * @param string $pattern
     * @param int    $offset
     *
     * @return null|string Null if pattern doesn't match
     */
    private function _regexMatch(string $pattern, int &$offset): ?string
    {
        $idx = $offset;
        if (!preg_match($pattern, substr($this->_dn, $idx), $match)) {
            return null;
        }
        $idx += strlen($match[0]);
        $offset = $idx;
        return end($match);
    }

    /**
     * Skip consecutive spaces.
     *
     * @param int $offset
     */
    private function _skipWs(int &$offset): void
    {
        $idx = $offset;
        while ($idx < $this->_len) {
            if (' ' != $this->_dn[$idx]) {
                break;
            }
            ++$idx;
        }
        $offset = $idx;
    }
}


1		<?php
2
3		declare(strict_types = 1);
4
5		namespace Sop\X501\DN;
6
7		use Sop\ASN1\Element;
8		use Sop\ASN1\Exception\DecodeException;
9
10		/**
11		* Distinguished Name parsing conforming to RFC 2253 and RFC 1779.
12		*
13		* @see https://tools.ietf.org/html/rfc1779
14		* @see https://tools.ietf.org/html/rfc2253
15		*/
16		class DNParser
17		{
18		/**
19		* RFC 2253 special characters.
20		*
21		* @var string
22		*/
23		const SPECIAL_CHARS = ',=+<>#;';
24
25		/**
26		* DN string.
27		*
28		* @var string
29		*/
30		private $_dn;
31
32		/**
33		* DN string length.
34		*
35		* @var int
36		*/
37		private $_len;
38
39		/**
40		* Constructor.
41		*
42		* @param string $dn Distinguised name
43		*/
44	70	protected function __construct(string $dn)
45		{
46	70	$this->_dn = $dn;
47	70	$this->_len = strlen($dn);
48	70	}
49
50		/**
51		* Parse distinguished name string to name-components.
52		*
53		* @param string $dn
54		*
55		* @return array
56		*/
57	70	public static function parseString(string $dn): array
58		{
59	70	$parser = new self($dn);
60	70	return $parser->parse();
61		}
62
63		/**
64		* Escape a AttributeValue string conforming to RFC 2253.
65		*
66		* @see https://tools.ietf.org/html/rfc2253#section-2.4
67		*
68		* @param string $str
69		*
70		* @return string
71		*/
72	31	public static function escapeString(string $str): string
73		{
74		// one of the characters ",", "+", """, "\", "<", ">" or ";"
75	31	$str = preg_replace('/([,\+"\\\<\>;])/u', '\\\\$1', $str);
76		// a space character occurring at the end of the string
77	31	$str = preg_replace('/( )$/u', '\\\\$1', $str);
78		// a space or "#" character occurring at the beginning of the string
79	31	$str = preg_replace('/^([ #])/u', '\\\\$1', $str);
80		// implementation specific special characters
81	31	$str = preg_replace_callback('/([\pC])/u',
82		function ($m) {
83	2	$octets = str_split(bin2hex($m[1]), 2);
84	2	return implode('',
85	2	array_map(
86		function ($octet) {
87	2	return '\\' . strtoupper($octet);
88	2	}, $octets));
89	31	}, $str);
90	31	return $str;
91		}
92
93		/**
94		* Parse DN to name-components.
95		*
96		* @throws \RuntimeException
97		*
98		* @return array
99		*/
100	70	protected function parse(): array
101		{
102	70	$offset = 0;
103	70	$name = $this->_parseName($offset);
104	62	if ($offset < $this->_len) {
105	1	$remains = substr($this->_dn, $offset);
106	1	throw new \UnexpectedValueException(sprintf(
107	1	'Parser finished before the end of string, remaining: %s',
108	1	$remains));
109		}
110	61	return $name;
111		}
112
113		/**
114		* Parse 'name'.
115		*
116		* name-component *("," name-component)
117		*
118		* @param int $offset
119		*
120		* @return array Array of name-components
121		*/
122	70	private function _parseName(int &$offset): array
123		{
124	70	$idx = $offset;
125	70	$names = [];
126	70	while ($idx < $this->_len) {
127	70	$names[] = $this->_parseNameComponent($idx);
128	62	if ($idx >= $this->_len) {
129	61	break;
130		}
131	20	$this->_skipWs($idx);
132	20	if (',' != $this->_dn[$idx] && ';' != $this->_dn[$idx]) {
133	1	break;
134		}
135	19	++$idx;
136	19	$this->_skipWs($idx);
137		}
138	62	$offset = $idx;
139	62	return array_reverse($names);
140		}
141
142		/**
143		* Parse 'name-component'.
144		*
145		* attributeTypeAndValue *("+" attributeTypeAndValue)
146		*
147		* @param int $offset
148		*
149		* @return array Array of [type, value] tuples
150		*/
151	70	private function _parseNameComponent(int &$offset): array
152		{
153	70	$idx = $offset;
154	70	$tvpairs = [];
155	70	while ($idx < $this->_len) {
156	70	$tvpairs[] = $this->_parseAttrTypeAndValue($idx);
157	62	$this->_skipWs($idx);
158	62	if ($idx >= $this->_len \|\| '+' != $this->_dn[$idx]) {
159	62	break;
160		}
161	10	++$idx;
162	10	$this->_skipWs($idx);
163		}
164	62	$offset = $idx;
165	62	return $tvpairs;
166		}
167
168		/**
169		* Parse 'attributeTypeAndValue'.
170		*
171		* attributeType "=" attributeValue
172		*
173		* @param int $offset
174		*
175		* @throws \UnexpectedValueException
176		*
177		* @return array A tuple of [type, value]. Value may be either a string or
178		* an Element, if it's encoded as hexstring.
179		*/
180	70	private function _parseAttrTypeAndValue(int &$offset): array
181		{
182	70	$idx = $offset;
183	70	$type = $this->_parseAttrType($idx);
184	69	$this->_skipWs($idx);
185	69	if ($idx >= $this->_len \|\| '=' != $this->_dn[$idx++]) {
186	1	throw new \UnexpectedValueException('Invalid type and value pair.');
187		}
188	68	$this->_skipWs($idx);
189		// hexstring
190	68	if ($idx < $this->_len && '#' == $this->_dn[$idx]) {
191	8	++$idx;
192	8	$data = $this->_parseAttrHexValue($idx);
193		try {
194	7	$value = Element::fromDER($data);
195	1	} catch (DecodeException $e) {
196	1	throw new \UnexpectedValueException(
197	7	'Invalid DER encoding from hexstring.', 0, $e);
198		}
199		} else {
200	60	$value = $this->_parseAttrStringValue($idx);
201		}
202	62	$offset = $idx;
203	62	return [$type, $value];
204		}
205
206		/**
207		* Parse 'attributeType'.
208		*
209		* (ALPHA 1*keychar) / oid
210		*
211		* @param int $offset
212		*
213		* @throws \UnexpectedValueException
214		*
215		* @return string
216		*/
217	70	private function _parseAttrType(int &$offset): string
218		{
219	70	$idx = $offset;
220		// dotted OID
221	70	$type = $this->_regexMatch('/^(?:oid\.)?([0-9]+(?:\.[0-9]+)*)/i', $idx);
222	70	if (null === $type) {
223		// name
224	63	$type = $this->_regexMatch('/^[a-z][a-z0-9\-]*/i', $idx);
225	63	if (null === $type) {
226	1	throw new \UnexpectedValueException('Invalid attribute type.');
227		}
228		}
229	69	$offset = $idx;
230	69	return $type;
231		}
232
233		/**
234		* Parse 'attributeValue' of string type.
235		*
236		* @param int $offset
237		*
238		* @throws \UnexpectedValueException
239		*
240		* @return string
241		*/
242	60	private function _parseAttrStringValue(int &$offset): string
243		{
244	60	$idx = $offset;
245	60	if ($idx >= $this->_len) {
246	2	return '';
247		}
248	58	if ('"' == $this->_dn[$idx]) { // quoted string
249	4	$val = $this->_parseQuotedAttrString($idx);
250		} else { // string
251	54	$val = $this->_parseAttrString($idx);
252		}
253	54	$offset = $idx;
254	54	return $val;
255		}
256
257		/**
258		* Parse plain 'attributeValue' string.
259		*
260		* @param int $offset
261		*
262		* @throws \UnexpectedValueException
263		*
264		* @return string
265		*/
266	54	private function _parseAttrString(int &$offset): string
267		{
268	54	$idx = $offset;
269	54	$val = '';
270	54	$wsidx = null;
271	54	while ($idx < $this->_len) {
272	54	$c = $this->_dn[$idx];
273		// pair (escape sequence)
274	54	if ('\\' == $c) {
275	10	++$idx;
276	10	$val .= $this->_parsePairAfterSlash($idx);
277	7	$wsidx = null;
278	7	continue;
279		}
280	49	if ('"' == $c) {
281	1	throw new \UnexpectedValueException('Unexpected quotation.');
282		}
283	49	if (false !== strpos(self::SPECIAL_CHARS, $c)) {
284	27	break;
285		}
286		// keep track of the first consecutive whitespace
287	49	if (' ' == $c) {
288	8	if (null === $wsidx) {
289	8	$wsidx = $idx;
290		}
291		} else {
292	49	$wsidx = null;
293		}
294		// stringchar
295	49	$val .= $c;
296	49	++$idx;
297		}
298		// if there was non-escaped whitespace in the end of the value
299	50	if (null !== $wsidx) {
300	5	$val = substr($val, 0, -($idx - $wsidx));
301		}
302	50	$offset = $idx;
303	50	return $val;
304		}
305
306		/**
307		* Parse quoted 'attributeValue' string.
308		*
309		* @param int $offset Offset to starting quote
310		*
311		* @throws \UnexpectedValueException
312		*
313		* @return string
314		*/
315	4	private function _parseQuotedAttrString(int &$offset): string
316		{
317	4	$idx = $offset + 1;
318	4	$val = '';
319	4	while ($idx < $this->_len) {
320	4	$c = $this->_dn[$idx];
321	4	if ('\\' == $c) { // pair
322	1	++$idx;
323	1	$val .= $this->_parsePairAfterSlash($idx);
324	1	continue;
325		}
326	4	if ('"' == $c) {
327	4	++$idx;
328	4	break;
329		}
330	4	$val .= $c;
331	4	++$idx;
332		}
333	4	$offset = $idx;
334	4	return $val;
335		}
336
337		/**
338		* Parse 'attributeValue' of binary type.
339		*
340		* @param int $offset
341		*
342		* @throws \UnexpectedValueException
343		*
344		* @return string
345		*/
346	8	private function _parseAttrHexValue(int &$offset): string
347		{
348	8	$idx = $offset;
349	8	$hexstr = $this->_regexMatch('/^(?:[0-9a-f]{2})+/i', $idx);
350	8	if (null === $hexstr) {
351	1	throw new \UnexpectedValueException('Invalid hexstring.');
352		}
353	7	$data = hex2bin($hexstr);
354	7	$offset = $idx;
355	7	return $data;
356		}
357
358		/**
359		* Parse 'pair' after leading slash.
360		*
361		* @param int $offset
362		*
363		* @throws \UnexpectedValueException
364		*
365		* @return string
366		*/
367	11	private function _parsePairAfterSlash(int &$offset): string
368		{
369	11	$idx = $offset;
370	11	if ($idx >= $this->_len) {
371	1	throw new \UnexpectedValueException(
372	1	'Unexpected end of escape sequence.');
373		}
374	10	$c = $this->_dn[$idx++];
375		// special \| \ \| " \| SPACE
376	10	if (false !== strpos(self::SPECIAL_CHARS . '\\" ', $c)) {
377	7	$val = $c;
378		} else { // hexpair
379	3	if ($idx >= $this->_len) {
380	1	throw new \UnexpectedValueException('Unexpected end of hexpair.');
381		}
382	2	$val = @hex2bin($c . $this->_dn[$idx++]);
383	2	if (false === $val) {
384	1	throw new \UnexpectedValueException('Invalid hexpair.');
385		}
386		}
387	8	$offset = $idx;
388	8	return $val;
389		}
390
391		/**
392		* Match DN to pattern and extract the last capture group.
393		*
394		* Updates offset to fully matched pattern.
395		*
396		* @param string $pattern
397		* @param int $offset
398		*
399		* @return null\|string Null if pattern doesn't match
400		*/
401	70	private function _regexMatch(string $pattern, int &$offset): ?string
402		{
403	70	$idx = $offset;
404	70	if (!preg_match($pattern, substr($this->_dn, $idx), $match)) {
405	63	return null;
406		}
407	69	$idx += strlen($match[0]);
408	69	$offset = $idx;
409	69	return end($match);
410		}
411
412		/**
413		* Skip consecutive spaces.
414		*
415		* @param int $offset
416		*/
417	69	private function _skipWs(int &$offset): void
418		{
419	69	$idx = $offset;
420	69	while ($idx < $this->_len) {
421	68	if (' ' != $this->_dn[$idx]) {
422	68	break;
423		}
424	5	++$idx;
425		}
426	69	$offset = $idx;
427	69	}
428		}
429

sop / x501

DNParser::_skipWs() A last analyzed 2019-06-28 10:37 UTC

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DNParser::_skipWs() A
last analyzed 2019-06-28 10:37 UTC