This file is indexed.

/usr/share/php/HTMLPurifier/Lexer/DirectLex.php is in php-htmlpurifier 4.6.0-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
<?php

/**
 * Our in-house implementation of a parser.
 *
 * A pure PHP parser, DirectLex has absolutely no dependencies, making
 * it a reasonably good default for PHP4.  Written with efficiency in mind,
 * it can be four times faster than HTMLPurifier_Lexer_PEARSax3, although it
 * pales in comparison to HTMLPurifier_Lexer_DOMLex.
 *
 * @todo Reread XML spec and document differences.
 */
class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
{
    /**
     * @type bool
     */
    public $tracksLineNumbers = true;

    /**
     * Whitespace characters for str(c)spn.
     * @type string
     */
    protected $_whitespace = "\x20\x09\x0D\x0A";

    /**
     * Callback function for script CDATA fudge
     * @param array $matches, in form of array(opening tag, contents, closing tag)
     * @return string
     */
    protected function scriptCallback($matches)
    {
        return $matches[1] . htmlspecialchars($matches[2], ENT_COMPAT, 'UTF-8') . $matches[3];
    }

    /**
     * @param String $html
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return array|HTMLPurifier_Token[]
     */
    public function tokenizeHTML($html, $config, $context)
    {
        // special normalization for script tags without any armor
        // our "armor" heurstic is a < sign any number of whitespaces after
        // the first script tag
        if ($config->get('HTML.Trusted')) {
            $html = preg_replace_callback(
                '#(<script[^>]*>)(\s*[^<].+?)(</script>)#si',
                array($this, 'scriptCallback'),
                $html
            );
        }

        $html = $this->normalize($html, $config, $context);

        $cursor = 0; // our location in the text
        $inside_tag = false; // whether or not we're parsing the inside of a tag
        $array = array(); // result array

        // This is also treated to mean maintain *column* numbers too
        $maintain_line_numbers = $config->get('Core.MaintainLineNumbers');

        if ($maintain_line_numbers === null) {
            // automatically determine line numbering by checking
            // if error collection is on
            $maintain_line_numbers = $config->get('Core.CollectErrors');
        }

        if ($maintain_line_numbers) {
            $current_line = 1;
            $current_col = 0;
            $length = strlen($html);
        } else {
            $current_line = false;
            $current_col = false;
            $length = false;
        }
        $context->register('CurrentLine', $current_line);
        $context->register('CurrentCol', $current_col);
        $nl = "\n";
        // how often to manually recalculate. This will ALWAYS be right,
        // but it's pretty wasteful. Set to 0 to turn off
        $synchronize_interval = $config->get('Core.DirectLexLineNumberSyncInterval');

        $e = false;
        if ($config->get('Core.CollectErrors')) {
            $e =& $context->get('ErrorCollector');
        }

        // for testing synchronization
        $loops = 0;

        while (++$loops) {
            // $cursor is either at the start of a token, or inside of
            // a tag (i.e. there was a < immediately before it), as indicated
            // by $inside_tag

            if ($maintain_line_numbers) {
                // $rcursor, however, is always at the start of a token.
                $rcursor = $cursor - (int)$inside_tag;

                // Column number is cheap, so we calculate it every round.
                // We're interested at the *end* of the newline string, so
                // we need to add strlen($nl) == 1 to $nl_pos before subtracting it
                // from our "rcursor" position.
                $nl_pos = strrpos($html, $nl, $rcursor - $length);
                $current_col = $rcursor - (is_bool($nl_pos) ? 0 : $nl_pos + 1);

                // recalculate lines
                if ($synchronize_interval && // synchronization is on
                    $cursor > 0 && // cursor is further than zero
                    $loops % $synchronize_interval === 0) { // time to synchronize!
                    $current_line = 1 + $this->substrCount($html, $nl, 0, $cursor);
                }
            }

            $position_next_lt = strpos($html, '<', $cursor);
            $position_next_gt = strpos($html, '>', $cursor);

            // triggers on "<b>asdf</b>" but not "asdf <b></b>"
            // special case to set up context
            if ($position_next_lt === $cursor) {
                $inside_tag = true;
                $cursor++;
            }

            if (!$inside_tag && $position_next_lt !== false) {
                // We are not inside tag and there still is another tag to parse
                $token = new
                HTMLPurifier_Token_Text(
                    $this->parseData(
                        substr(
                            $html,
                            $cursor,
                            $position_next_lt - $cursor
                        )
                    )
                );
                if ($maintain_line_numbers) {
                    $token->rawPosition($current_line, $current_col);
                    $current_line += $this->substrCount($html, $nl, $cursor, $position_next_lt - $cursor);
                }
                $array[] = $token;
                $cursor = $position_next_lt + 1;
                $inside_tag = true;
                continue;
            } elseif (!$inside_tag) {
                // We are not inside tag but there are no more tags
                // If we're already at the end, break
                if ($cursor === strlen($html)) {
                    break;
                }
                // Create Text of rest of string
                $token = new
                HTMLPurifier_Token_Text(
                    $this->parseData(
                        substr(
                            $html,
                            $cursor
                        )
                    )
                );
                if ($maintain_line_numbers) {
                    $token->rawPosition($current_line, $current_col);
                }
                $array[] = $token;
                break;
            } elseif ($inside_tag && $position_next_gt !== false) {
                // We are in tag and it is well formed
                // Grab the internals of the tag
                $strlen_segment = $position_next_gt - $cursor;

                if ($strlen_segment < 1) {
                    // there's nothing to process!
                    $token = new HTMLPurifier_Token_Text('<');
                    $cursor++;
                    continue;
                }

                $segment = substr($html, $cursor, $strlen_segment);

                if ($segment === false) {
                    // somehow, we attempted to access beyond the end of
                    // the string, defense-in-depth, reported by Nate Abele
                    break;
                }

                // Check if it's a comment
                if (substr($segment, 0, 3) === '!--') {
                    // re-determine segment length, looking for -->
                    $position_comment_end = strpos($html, '-->', $cursor);
                    if ($position_comment_end === false) {
                        // uh oh, we have a comment that extends to
                        // infinity. Can't be helped: set comment
                        // end position to end of string
                        if ($e) {
                            $e->send(E_WARNING, 'Lexer: Unclosed comment');
                        }
                        $position_comment_end = strlen($html);
                        $end = true;
                    } else {
                        $end = false;
                    }
                    $strlen_segment = $position_comment_end - $cursor;
                    $segment = substr($html, $cursor, $strlen_segment);
                    $token = new
                    HTMLPurifier_Token_Comment(
                        substr(
                            $segment,
                            3,
                            $strlen_segment - 3
                        )
                    );
                    if ($maintain_line_numbers) {
                        $token->rawPosition($current_line, $current_col);
                        $current_line += $this->substrCount($html, $nl, $cursor, $strlen_segment);
                    }
                    $array[] = $token;
                    $cursor = $end ? $position_comment_end : $position_comment_end + 3;
                    $inside_tag = false;
                    continue;
                }

                // Check if it's an end tag
                $is_end_tag = (strpos($segment, '/') === 0);
                if ($is_end_tag) {
                    $type = substr($segment, 1);
                    $token = new HTMLPurifier_Token_End($type);
                    if ($maintain_line_numbers) {
                        $token->rawPosition($current_line, $current_col);
                        $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                    }
                    $array[] = $token;
                    $inside_tag = false;
                    $cursor = $position_next_gt + 1;
                    continue;
                }

                // Check leading character is alnum, if not, we may
                // have accidently grabbed an emoticon. Translate into
                // text and go our merry way
                if (!ctype_alpha($segment[0])) {
                    // XML:  $segment[0] !== '_' && $segment[0] !== ':'
                    if ($e) {
                        $e->send(E_NOTICE, 'Lexer: Unescaped lt');
                    }
                    $token = new HTMLPurifier_Token_Text('<');
                    if ($maintain_line_numbers) {
                        $token->rawPosition($current_line, $current_col);
                        $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                    }
                    $array[] = $token;
                    $inside_tag = false;
                    continue;
                }

                // Check if it is explicitly self closing, if so, remove
                // trailing slash. Remember, we could have a tag like <br>, so
                // any later token processing scripts must convert improperly
                // classified EmptyTags from StartTags.
                $is_self_closing = (strrpos($segment, '/') === $strlen_segment - 1);
                if ($is_self_closing) {
                    $strlen_segment--;
                    $segment = substr($segment, 0, $strlen_segment);
                }

                // Check if there are any attributes
                $position_first_space = strcspn($segment, $this->_whitespace);

                if ($position_first_space >= $strlen_segment) {
                    if ($is_self_closing) {
                        $token = new HTMLPurifier_Token_Empty($segment);
                    } else {
                        $token = new HTMLPurifier_Token_Start($segment);
                    }
                    if ($maintain_line_numbers) {
                        $token->rawPosition($current_line, $current_col);
                        $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                    }
                    $array[] = $token;
                    $inside_tag = false;
                    $cursor = $position_next_gt + 1;
                    continue;
                }

                // Grab out all the data
                $type = substr($segment, 0, $position_first_space);
                $attribute_string =
                    trim(
                        substr(
                            $segment,
                            $position_first_space
                        )
                    );
                if ($attribute_string) {
                    $attr = $this->parseAttributeString(
                        $attribute_string,
                        $config,
                        $context
                    );
                } else {
                    $attr = array();
                }

                if ($is_self_closing) {
                    $token = new HTMLPurifier_Token_Empty($type, $attr);
                } else {
                    $token = new HTMLPurifier_Token_Start($type, $attr);
                }
                if ($maintain_line_numbers) {
                    $token->rawPosition($current_line, $current_col);
                    $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                }
                $array[] = $token;
                $cursor = $position_next_gt + 1;
                $inside_tag = false;
                continue;
            } else {
                // inside tag, but there's no ending > sign
                if ($e) {
                    $e->send(E_WARNING, 'Lexer: Missing gt');
                }
                $token = new
                HTMLPurifier_Token_Text(
                    '<' .
                    $this->parseData(
                        substr($html, $cursor)
                    )
                );
                if ($maintain_line_numbers) {
                    $token->rawPosition($current_line, $current_col);
                }
                // no cursor scroll? Hmm...
                $array[] = $token;
                break;
            }
            break;
        }

        $context->destroy('CurrentLine');
        $context->destroy('CurrentCol');
        return $array;
    }

    /**
     * PHP 5.0.x compatible substr_count that implements offset and length
     * @param string $haystack
     * @param string $needle
     * @param int $offset
     * @param int $length
     * @return int
     */
    protected function substrCount($haystack, $needle, $offset, $length)
    {
        static $oldVersion;
        if ($oldVersion === null) {
            $oldVersion = version_compare(PHP_VERSION, '5.1', '<');
        }
        if ($oldVersion) {
            $haystack = substr($haystack, $offset, $length);
            return substr_count($haystack, $needle);
        } else {
            return substr_count($haystack, $needle, $offset, $length);
        }
    }

    /**
     * Takes the inside of an HTML tag and makes an assoc array of attributes.
     *
     * @param string $string Inside of tag excluding name.
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return array Assoc array of attributes.
     */
    public function parseAttributeString($string, $config, $context)
    {
        $string = (string)$string; // quick typecast

        if ($string == '') {
            return array();
        } // no attributes

        $e = false;
        if ($config->get('Core.CollectErrors')) {
            $e =& $context->get('ErrorCollector');
        }

        // let's see if we can abort as quickly as possible
        // one equal sign, no spaces => one attribute
        $num_equal = substr_count($string, '=');
        $has_space = strpos($string, ' ');
        if ($num_equal === 0 && !$has_space) {
            // bool attribute
            return array($string => $string);
        } elseif ($num_equal === 1 && !$has_space) {
            // only one attribute
            list($key, $quoted_value) = explode('=', $string);
            $quoted_value = trim($quoted_value);
            if (!$key) {
                if ($e) {
                    $e->send(E_ERROR, 'Lexer: Missing attribute key');
                }
                return array();
            }
            if (!$quoted_value) {
                return array($key => '');
            }
            $first_char = @$quoted_value[0];
            $last_char = @$quoted_value[strlen($quoted_value) - 1];

            $same_quote = ($first_char == $last_char);
            $open_quote = ($first_char == '"' || $first_char == "'");

            if ($same_quote && $open_quote) {
                // well behaved
                $value = substr($quoted_value, 1, strlen($quoted_value) - 2);
            } else {
                // not well behaved
                if ($open_quote) {
                    if ($e) {
                        $e->send(E_ERROR, 'Lexer: Missing end quote');
                    }
                    $value = substr($quoted_value, 1);
                } else {
                    $value = $quoted_value;
                }
            }
            if ($value === false) {
                $value = '';
            }
            return array($key => $this->parseData($value));
        }

        // setup loop environment
        $array = array(); // return assoc array of attributes
        $cursor = 0; // current position in string (moves forward)
        $size = strlen($string); // size of the string (stays the same)

        // if we have unquoted attributes, the parser expects a terminating
        // space, so let's guarantee that there's always a terminating space.
        $string .= ' ';

        $old_cursor = -1;
        while ($cursor < $size) {
            if ($old_cursor >= $cursor) {
                throw new Exception("Infinite loop detected");
            }
            $old_cursor = $cursor;

            $cursor += ($value = strspn($string, $this->_whitespace, $cursor));
            // grab the key

            $key_begin = $cursor; //we're currently at the start of the key

            // scroll past all characters that are the key (not whitespace or =)
            $cursor += strcspn($string, $this->_whitespace . '=', $cursor);

            $key_end = $cursor; // now at the end of the key

            $key = substr($string, $key_begin, $key_end - $key_begin);

            if (!$key) {
                if ($e) {
                    $e->send(E_ERROR, 'Lexer: Missing attribute key');
                }
                $cursor += 1 + strcspn($string, $this->_whitespace, $cursor + 1); // prevent infinite loop
                continue; // empty key
            }

            // scroll past all whitespace
            $cursor += strspn($string, $this->_whitespace, $cursor);

            if ($cursor >= $size) {
                $array[$key] = $key;
                break;
            }

            // if the next character is an equal sign, we've got a regular
            // pair, otherwise, it's a bool attribute
            $first_char = @$string[$cursor];

            if ($first_char == '=') {
                // key="value"

                $cursor++;
                $cursor += strspn($string, $this->_whitespace, $cursor);

                if ($cursor === false) {
                    $array[$key] = '';
                    break;
                }

                // we might be in front of a quote right now

                $char = @$string[$cursor];

                if ($char == '"' || $char == "'") {
                    // it's quoted, end bound is $char
                    $cursor++;
                    $value_begin = $cursor;
                    $cursor = strpos($string, $char, $cursor);
                    $value_end = $cursor;
                } else {
                    // it's not quoted, end bound is whitespace
                    $value_begin = $cursor;
                    $cursor += strcspn($string, $this->_whitespace, $cursor);
                    $value_end = $cursor;
                }

                // we reached a premature end
                if ($cursor === false) {
                    $cursor = $size;
                    $value_end = $cursor;
                }

                $value = substr($string, $value_begin, $value_end - $value_begin);
                if ($value === false) {
                    $value = '';
                }
                $array[$key] = $this->parseData($value);
                $cursor++;
            } else {
                // boolattr
                if ($key !== '') {
                    $array[$key] = $key;
                } else {
                    // purely theoretical
                    if ($e) {
                        $e->send(E_ERROR, 'Lexer: Missing attribute key');
                    }
                }
            }
        }
        return $array;
    }
}

// vim: et sw=4 sts=4