xref: /PHP-7.2/ext/standard/html.c (revision 0f8c1ee7)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 7                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2018 The PHP Group                                |
6    +----------------------------------------------------------------------+
7    | This source file is subject to version 3.01 of the PHP license,      |
8    | that is bundled with this package in the file LICENSE, and is        |
9    | available through the world-wide-web at the following url:           |
10    | http://www.php.net/license/3_01.txt                                  |
11    | If you did not receive a copy of the PHP license and are unable to   |
12    | obtain it through the world-wide-web, please send a note to          |
13    | license@php.net so we can mail you a copy immediately.               |
14    +----------------------------------------------------------------------+
15    | Authors: Rasmus Lerdorf <rasmus@php.net>                             |
16    |          Jaakko Hyvätti <jaakko.hyvatti@iki.fi>                      |
17    |          Wez Furlong    <wez@thebrainroom.com>                       |
18    |          Gustavo Lopes  <cataphract@php.net>                         |
19    +----------------------------------------------------------------------+
20 */
21 
22 /* $Id$ */
23 
24 /*
25  * HTML entity resources:
26  *
27  * http://www.unicode.org/Public/MAPPINGS/OBSOLETE/UNI2SGML.TXT
28  *
29  * XHTML 1.0 DTD
30  * http://www.w3.org/TR/2002/REC-xhtml1-20020801/dtds.html#h-A2
31  *
32  * From HTML 4.01 strict DTD:
33  * http://www.w3.org/TR/html4/HTMLlat1.ent
34  * http://www.w3.org/TR/html4/HTMLsymbol.ent
35  * http://www.w3.org/TR/html4/HTMLspecial.ent
36  *
37  * HTML 5:
38  * http://dev.w3.org/html5/spec/Overview.html#named-character-references
39  */
40 
41 #include "php.h"
42 #ifdef PHP_WIN32
43 #include "config.w32.h"
44 #else
45 #include <php_config.h>
46 #endif
47 #include "php_standard.h"
48 #include "php_string.h"
49 #include "SAPI.h"
50 #if HAVE_LOCALE_H
51 #include <locale.h>
52 #endif
53 #if HAVE_LANGINFO_H
54 #include <langinfo.h>
55 #endif
56 
57 #include <zend_hash.h>
58 #include "html_tables.h"
59 
60 /* Macro for disabling flag of translation of non-basic entities where this isn't supported.
61  * Not appropriate for html_entity_decode/htmlspecialchars_decode */
62 #define LIMIT_ALL(all, doctype, charset) do { \
63 	(all) = (all) && !CHARSET_PARTIAL_SUPPORT((charset)) && ((doctype) != ENT_HTML_DOC_XML1); \
64 } while (0)
65 
66 #define MB_FAILURE(pos, advance) do { \
67 	*cursor = pos + (advance); \
68 	*status = FAILURE; \
69 	return 0; \
70 } while (0)
71 
72 #define CHECK_LEN(pos, chars_need) ((str_len - (pos)) >= (chars_need))
73 
74 /* valid as single byte character or leading byte */
75 #define utf8_lead(c)  ((c) < 0x80 || ((c) >= 0xC2 && (c) <= 0xF4))
76 /* whether it's actually valid depends on other stuff;
77  * this macro cannot check for non-shortest forms, surrogates or
78  * code points above 0x10FFFF */
79 #define utf8_trail(c) ((c) >= 0x80 && (c) <= 0xBF)
80 
81 #define gb2312_lead(c) ((c) != 0x8E && (c) != 0x8F && (c) != 0xA0 && (c) != 0xFF)
82 #define gb2312_trail(c) ((c) >= 0xA1 && (c) <= 0xFE)
83 
84 #define sjis_lead(c) ((c) != 0x80 && (c) != 0xA0 && (c) < 0xFD)
85 #define sjis_trail(c) ((c) >= 0x40  && (c) != 0x7F && (c) < 0xFD)
86 
87 /* {{{ get_default_charset
88  */
get_default_charset(void)89 static char *get_default_charset(void) {
90 	if (PG(internal_encoding) && PG(internal_encoding)[0]) {
91 		return PG(internal_encoding);
92 	} else if (SG(default_charset) && SG(default_charset)[0] ) {
93 		return SG(default_charset);
94 	}
95 	return NULL;
96 }
97 /* }}} */
98 
99 /* {{{ get_next_char
100  */
get_next_char(enum entity_charset charset,const unsigned char * str,size_t str_len,size_t * cursor,int * status)101 static inline unsigned int get_next_char(
102 		enum entity_charset charset,
103 		const unsigned char *str,
104 		size_t str_len,
105 		size_t *cursor,
106 		int *status)
107 {
108 	size_t pos = *cursor;
109 	unsigned int this_char = 0;
110 
111 	*status = SUCCESS;
112 	assert(pos <= str_len);
113 
114 	if (!CHECK_LEN(pos, 1))
115 		MB_FAILURE(pos, 1);
116 
117 	switch (charset) {
118 	case cs_utf_8:
119 		{
120 			/* We'll follow strategy 2. from section 3.6.1 of UTR #36:
121 			 * "In a reported illegal byte sequence, do not include any
122 			 *  non-initial byte that encodes a valid character or is a leading
123 			 *  byte for a valid sequence." */
124 			unsigned char c;
125 			c = str[pos];
126 			if (c < 0x80) {
127 				this_char = c;
128 				pos++;
129 			} else if (c < 0xc2) {
130 				MB_FAILURE(pos, 1);
131 			} else if (c < 0xe0) {
132 				if (!CHECK_LEN(pos, 2))
133 					MB_FAILURE(pos, 1);
134 
135 				if (!utf8_trail(str[pos + 1])) {
136 					MB_FAILURE(pos, utf8_lead(str[pos + 1]) ? 1 : 2);
137 				}
138 				this_char = ((c & 0x1f) << 6) | (str[pos + 1] & 0x3f);
139 				if (this_char < 0x80) { /* non-shortest form */
140 					MB_FAILURE(pos, 2);
141 				}
142 				pos += 2;
143 			} else if (c < 0xf0) {
144 				size_t avail = str_len - pos;
145 
146 				if (avail < 3 ||
147 						!utf8_trail(str[pos + 1]) || !utf8_trail(str[pos + 2])) {
148 					if (avail < 2 || utf8_lead(str[pos + 1]))
149 						MB_FAILURE(pos, 1);
150 					else if (avail < 3 || utf8_lead(str[pos + 2]))
151 						MB_FAILURE(pos, 2);
152 					else
153 						MB_FAILURE(pos, 3);
154 				}
155 
156 				this_char = ((c & 0x0f) << 12) | ((str[pos + 1] & 0x3f) << 6) | (str[pos + 2] & 0x3f);
157 				if (this_char < 0x800) { /* non-shortest form */
158 					MB_FAILURE(pos, 3);
159 				} else if (this_char >= 0xd800 && this_char <= 0xdfff) { /* surrogate */
160 					MB_FAILURE(pos, 3);
161 				}
162 				pos += 3;
163 			} else if (c < 0xf5) {
164 				size_t avail = str_len - pos;
165 
166 				if (avail < 4 ||
167 						!utf8_trail(str[pos + 1]) || !utf8_trail(str[pos + 2]) ||
168 						!utf8_trail(str[pos + 3])) {
169 					if (avail < 2 || utf8_lead(str[pos + 1]))
170 						MB_FAILURE(pos, 1);
171 					else if (avail < 3 || utf8_lead(str[pos + 2]))
172 						MB_FAILURE(pos, 2);
173 					else if (avail < 4 || utf8_lead(str[pos + 3]))
174 						MB_FAILURE(pos, 3);
175 					else
176 						MB_FAILURE(pos, 4);
177 				}
178 
179 				this_char = ((c & 0x07) << 18) | ((str[pos + 1] & 0x3f) << 12) | ((str[pos + 2] & 0x3f) << 6) | (str[pos + 3] & 0x3f);
180 				if (this_char < 0x10000 || this_char > 0x10FFFF) { /* non-shortest form or outside range */
181 					MB_FAILURE(pos, 4);
182 				}
183 				pos += 4;
184 			} else {
185 				MB_FAILURE(pos, 1);
186 			}
187 		}
188 		break;
189 
190 	case cs_big5:
191 		/* reference http://demo.icu-project.org/icu-bin/convexp?conv=big5 */
192 		{
193 			unsigned char c = str[pos];
194 			if (c >= 0x81 && c <= 0xFE) {
195 				unsigned char next;
196 				if (!CHECK_LEN(pos, 2))
197 					MB_FAILURE(pos, 1);
198 
199 				next = str[pos + 1];
200 
201 				if ((next >= 0x40 && next <= 0x7E) ||
202 						(next >= 0xA1 && next <= 0xFE)) {
203 					this_char = (c << 8) | next;
204 				} else {
205 					MB_FAILURE(pos, 1);
206 				}
207 				pos += 2;
208 			} else {
209 				this_char = c;
210 				pos += 1;
211 			}
212 		}
213 		break;
214 
215 	case cs_big5hkscs:
216 		{
217 			unsigned char c = str[pos];
218 			if (c >= 0x81 && c <= 0xFE) {
219 				unsigned char next;
220 				if (!CHECK_LEN(pos, 2))
221 					MB_FAILURE(pos, 1);
222 
223 				next = str[pos + 1];
224 
225 				if ((next >= 0x40 && next <= 0x7E) ||
226 						(next >= 0xA1 && next <= 0xFE)) {
227 					this_char = (c << 8) | next;
228 				} else if (next != 0x80 && next != 0xFF) {
229 					MB_FAILURE(pos, 1);
230 				} else {
231 					MB_FAILURE(pos, 2);
232 				}
233 				pos += 2;
234 			} else {
235 				this_char = c;
236 				pos += 1;
237 			}
238 		}
239 		break;
240 
241 	case cs_gb2312: /* EUC-CN */
242 		{
243 			unsigned char c = str[pos];
244 			if (c >= 0xA1 && c <= 0xFE) {
245 				unsigned char next;
246 				if (!CHECK_LEN(pos, 2))
247 					MB_FAILURE(pos, 1);
248 
249 				next = str[pos + 1];
250 
251 				if (gb2312_trail(next)) {
252 					this_char = (c << 8) | next;
253 				} else if (gb2312_lead(next)) {
254 					MB_FAILURE(pos, 1);
255 				} else {
256 					MB_FAILURE(pos, 2);
257 				}
258 				pos += 2;
259 			} else if (gb2312_lead(c)) {
260 				this_char = c;
261 				pos += 1;
262 			} else {
263 				MB_FAILURE(pos, 1);
264 			}
265 		}
266 		break;
267 
268 	case cs_sjis:
269 		{
270 			unsigned char c = str[pos];
271 			if ((c >= 0x81 && c <= 0x9F) || (c >= 0xE0 && c <= 0xFC)) {
272 				unsigned char next;
273 				if (!CHECK_LEN(pos, 2))
274 					MB_FAILURE(pos, 1);
275 
276 				next = str[pos + 1];
277 
278 				if (sjis_trail(next)) {
279 					this_char = (c << 8) | next;
280 				} else if (sjis_lead(next)) {
281 					MB_FAILURE(pos, 1);
282 				} else {
283 					MB_FAILURE(pos, 2);
284 				}
285 				pos += 2;
286 			} else if (c < 0x80 || (c >= 0xA1 && c <= 0xDF)) {
287 				this_char = c;
288 				pos += 1;
289 			} else {
290 				MB_FAILURE(pos, 1);
291 			}
292 		}
293 		break;
294 
295 	case cs_eucjp:
296 		{
297 			unsigned char c = str[pos];
298 
299 			if (c >= 0xA1 && c <= 0xFE) {
300 				unsigned next;
301 				if (!CHECK_LEN(pos, 2))
302 					MB_FAILURE(pos, 1);
303 				next = str[pos + 1];
304 
305 				if (next >= 0xA1 && next <= 0xFE) {
306 					/* this a jis kanji char */
307 					this_char = (c << 8) | next;
308 				} else {
309 					MB_FAILURE(pos, (next != 0xA0 && next != 0xFF) ? 1 : 2);
310 				}
311 				pos += 2;
312 			} else if (c == 0x8E) {
313 				unsigned next;
314 				if (!CHECK_LEN(pos, 2))
315 					MB_FAILURE(pos, 1);
316 
317 				next = str[pos + 1];
318 				if (next >= 0xA1 && next <= 0xDF) {
319 					/* JIS X 0201 kana */
320 					this_char = (c << 8) | next;
321 				} else {
322 					MB_FAILURE(pos, (next != 0xA0 && next != 0xFF) ? 1 : 2);
323 				}
324 				pos += 2;
325 			} else if (c == 0x8F) {
326 				size_t avail = str_len - pos;
327 
328 				if (avail < 3 || !(str[pos + 1] >= 0xA1 && str[pos + 1] <= 0xFE) ||
329 						!(str[pos + 2] >= 0xA1 && str[pos + 2] <= 0xFE)) {
330 					if (avail < 2 || (str[pos + 1] != 0xA0 && str[pos + 1] != 0xFF))
331 						MB_FAILURE(pos, 1);
332 					else if (avail < 3 || (str[pos + 2] != 0xA0 && str[pos + 2] != 0xFF))
333 						MB_FAILURE(pos, 2);
334 					else
335 						MB_FAILURE(pos, 3);
336 				} else {
337 					/* JIS X 0212 hojo-kanji */
338 					this_char = (c << 16) | (str[pos + 1] << 8) | str[pos + 2];
339 				}
340 				pos += 3;
341 			} else if (c != 0xA0 && c != 0xFF) {
342 				/* character encoded in 1 code unit */
343 				this_char = c;
344 				pos += 1;
345 			} else {
346 				MB_FAILURE(pos, 1);
347 			}
348 		}
349 		break;
350 	default:
351 		/* single-byte charsets */
352 		this_char = str[pos++];
353 		break;
354 	}
355 
356 	*cursor = pos;
357   	return this_char;
358 }
359 /* }}} */
360 
361 /* {{{ php_next_utf8_char
362  * Public interface for get_next_char used with UTF-8 */
php_next_utf8_char(const unsigned char * str,size_t str_len,size_t * cursor,int * status)363  PHPAPI unsigned int php_next_utf8_char(
364 		const unsigned char *str,
365 		size_t str_len,
366 		size_t *cursor,
367 		int *status)
368 {
369 	return get_next_char(cs_utf_8, str, str_len, cursor, status);
370 }
371 /* }}} */
372 
373 /* {{{ entity_charset determine_charset
374  * returns the charset identifier based on current locale or a hint.
375  * defaults to UTF-8 */
determine_charset(char * charset_hint)376 static enum entity_charset determine_charset(char *charset_hint)
377 {
378 	size_t i;
379 	enum entity_charset charset = cs_utf_8;
380 	size_t len = 0;
381 	const zend_encoding *zenc;
382 
383 	/* Default is now UTF-8 */
384 	if (charset_hint == NULL)
385 		return cs_utf_8;
386 
387 	if ((len = strlen(charset_hint)) != 0) {
388 		goto det_charset;
389 	}
390 
391 	zenc = zend_multibyte_get_internal_encoding();
392 	if (zenc != NULL) {
393 		charset_hint = (char *)zend_multibyte_get_encoding_name(zenc);
394 		if (charset_hint != NULL && (len=strlen(charset_hint)) != 0) {
395 			if ((len == 4) /* sizeof (auto|pass) */ &&
396 					/* XXX should the "wchar" be ignored as well?? */
397 					(!memcmp("pass", charset_hint, 4) ||
398 					 !memcmp("auto", charset_hint, 4))) {
399 				charset_hint = NULL;
400 				len = 0;
401 			} else {
402 				goto det_charset;
403 			}
404 		}
405 	}
406 
407 	charset_hint = SG(default_charset);
408 	if (charset_hint != NULL && (len=strlen(charset_hint)) != 0) {
409 		goto det_charset;
410 	}
411 
412 	/* try to detect the charset for the locale */
413 #if HAVE_NL_LANGINFO && HAVE_LOCALE_H && defined(CODESET)
414 	charset_hint = nl_langinfo(CODESET);
415 	if (charset_hint != NULL && (len=strlen(charset_hint)) != 0) {
416 		goto det_charset;
417 	}
418 #endif
419 
420 #if HAVE_LOCALE_H
421 	/* try to figure out the charset from the locale */
422 	{
423 		char *localename;
424 		char *dot, *at;
425 
426 		/* lang[_territory][.codeset][@modifier] */
427 		localename = setlocale(LC_CTYPE, NULL);
428 
429 		dot = strchr(localename, '.');
430 		if (dot) {
431 			dot++;
432 			/* locale specifies a codeset */
433 			at = strchr(dot, '@');
434 			if (at)
435 				len = at - dot;
436 			else
437 				len = strlen(dot);
438 			charset_hint = dot;
439 		} else {
440 			/* no explicit name; see if the name itself
441 			 * is the charset */
442 			charset_hint = localename;
443 			len = strlen(charset_hint);
444 		}
445 	}
446 #endif
447 
448 det_charset:
449 
450 	if (charset_hint) {
451 		int found = 0;
452 
453 		/* now walk the charset map and look for the codeset */
454 		for (i = 0; i < sizeof(charset_map)/sizeof(charset_map[0]); i++) {
455 			if (len == charset_map[i].codeset_len &&
456 			    zend_binary_strcasecmp(charset_hint, len, charset_map[i].codeset, len) == 0) {
457 				charset = charset_map[i].charset;
458 				found = 1;
459 				break;
460 			}
461 		}
462 		if (!found) {
463 			php_error_docref(NULL, E_WARNING, "charset `%s' not supported, assuming utf-8",
464 					charset_hint);
465 		}
466 	}
467 	return charset;
468 }
469 /* }}} */
470 
471 /* {{{ php_utf32_utf8 */
php_utf32_utf8(unsigned char * buf,unsigned k)472 static inline size_t php_utf32_utf8(unsigned char *buf, unsigned k)
473 {
474 	size_t retval = 0;
475 
476 	/* assert(0x0 <= k <= 0x10FFFF); */
477 
478 	if (k < 0x80) {
479 		buf[0] = k;
480 		retval = 1;
481 	} else if (k < 0x800) {
482 		buf[0] = 0xc0 | (k >> 6);
483 		buf[1] = 0x80 | (k & 0x3f);
484 		retval = 2;
485 	} else if (k < 0x10000) {
486 		buf[0] = 0xe0 | (k >> 12);
487 		buf[1] = 0x80 | ((k >> 6) & 0x3f);
488 		buf[2] = 0x80 | (k & 0x3f);
489 		retval = 3;
490 	} else {
491 		buf[0] = 0xf0 | (k >> 18);
492 		buf[1] = 0x80 | ((k >> 12) & 0x3f);
493 		buf[2] = 0x80 | ((k >> 6) & 0x3f);
494 		buf[3] = 0x80 | (k & 0x3f);
495 		retval = 4;
496 	}
497 	/* UTF-8 has been restricted to max 4 bytes since RFC 3629 */
498 
499 	return retval;
500 }
501 /* }}} */
502 
503 /* {{{ php_mb2_int_to_char
504  * Convert back big endian int representation of sequence of one or two 8-bit code units. */
php_mb2_int_to_char(unsigned char * buf,unsigned k)505 static inline size_t php_mb2_int_to_char(unsigned char *buf, unsigned k)
506 {
507 	assert(k <= 0xFFFFU);
508 	/* one or two bytes */
509 	if (k <= 0xFFU) { /* 1 */
510 		buf[0] = k;
511 		return 1U;
512 	} else { /* 2 */
513 		buf[0] = k >> 8;
514 		buf[1] = k & 0xFFU;
515 		return 2U;
516 	}
517 }
518 /* }}} */
519 
520 /* {{{ php_mb3_int_to_char
521  * Convert back big endian int representation of sequence of one to three 8-bit code units.
522  * For EUC-JP. */
php_mb3_int_to_char(unsigned char * buf,unsigned k)523 static inline size_t php_mb3_int_to_char(unsigned char *buf, unsigned k)
524 {
525 	assert(k <= 0xFFFFFFU);
526 	/* one to three bytes */
527 	if (k <= 0xFFU) { /* 1 */
528 		buf[0] = k;
529 		return 1U;
530 	} else if (k <= 0xFFFFU) { /* 2 */
531 		buf[0] = k >> 8;
532 		buf[1] = k & 0xFFU;
533 		return 2U;
534 	} else {
535 		buf[0] = k >> 16;
536 		buf[1] = (k >> 8) & 0xFFU;
537 		buf[2] = k & 0xFFU;
538 		return 3U;
539 	}
540 }
541 /* }}} */
542 
543 
544 /* {{{ unimap_bsearc_cmp
545  * Binary search of unicode code points in unicode <--> charset mapping.
546  * Returns the code point in the target charset (whose mapping table was given) or 0 if
547  * the unicode code point is not in the table.
548  */
unimap_bsearch(const uni_to_enc * table,unsigned code_key_a,size_t num)549 static inline unsigned char unimap_bsearch(const uni_to_enc *table, unsigned code_key_a, size_t num)
550 {
551 	const uni_to_enc *l = table,
552 					 *h = &table[num-1],
553 					 *m;
554 	unsigned short code_key;
555 
556 	/* we have no mappings outside the BMP */
557 	if (code_key_a > 0xFFFFU)
558 		return 0;
559 
560 	code_key = (unsigned short) code_key_a;
561 
562 	while (l <= h) {
563 		m = l + (h - l) / 2;
564 		if (code_key < m->un_code_point)
565 			h = m - 1;
566 		else if (code_key > m->un_code_point)
567 			l = m + 1;
568 		else
569 			return m->cs_code;
570 	}
571 	return 0;
572 }
573 /* }}} */
574 
575 /* {{{ map_from_unicode */
map_from_unicode(unsigned code,enum entity_charset charset,unsigned * res)576 static inline int map_from_unicode(unsigned code, enum entity_charset charset, unsigned *res)
577 {
578 	unsigned char found;
579 	const uni_to_enc *table;
580 	size_t table_size;
581 
582 	switch (charset) {
583 	case cs_8859_1:
584 		/* identity mapping of code points to unicode */
585 		if (code > 0xFF) {
586 			return FAILURE;
587 		}
588 		*res = code;
589 		break;
590 
591 	case cs_8859_5:
592 		if (code <= 0xA0 || code == 0xAD /* soft hyphen */) {
593 			*res = code;
594 		} else if (code == 0x2116) {
595 			*res = 0xF0; /* numero sign */
596 		} else if (code == 0xA7) {
597 			*res = 0xFD; /* section sign */
598 		} else if (code >= 0x0401 && code <= 0x044F) {
599 			if (code == 0x040D || code == 0x0450 || code == 0x045D)
600 				return FAILURE;
601 			*res = code - 0x360;
602 		} else {
603 			return FAILURE;
604 		}
605 		break;
606 
607 	case cs_8859_15:
608 		if (code < 0xA4 || (code > 0xBE && code <= 0xFF)) {
609 			*res = code;
610 		} else { /* between A4 and 0xBE */
611 			found = unimap_bsearch(unimap_iso885915,
612 				code, sizeof(unimap_iso885915) / sizeof(*unimap_iso885915));
613 			if (found)
614 				*res = found;
615 			else
616 				return FAILURE;
617 		}
618 		break;
619 
620 	case cs_cp1252:
621 		if (code <= 0x7F || (code >= 0xA0 && code <= 0xFF)) {
622 			*res = code;
623 		} else {
624 			found = unimap_bsearch(unimap_win1252,
625 				code, sizeof(unimap_win1252) / sizeof(*unimap_win1252));
626 			if (found)
627 				*res = found;
628 			else
629 				return FAILURE;
630 		}
631 		break;
632 
633 	case cs_macroman:
634 		if (code == 0x7F)
635 			return FAILURE;
636 		table = unimap_macroman;
637 		table_size = sizeof(unimap_macroman) / sizeof(*unimap_macroman);
638 		goto table_over_7F;
639 	case cs_cp1251:
640 		table = unimap_win1251;
641 		table_size = sizeof(unimap_win1251) / sizeof(*unimap_win1251);
642 		goto table_over_7F;
643 	case cs_koi8r:
644 		table = unimap_koi8r;
645 		table_size = sizeof(unimap_koi8r) / sizeof(*unimap_koi8r);
646 		goto table_over_7F;
647 	case cs_cp866:
648 		table = unimap_cp866;
649 		table_size = sizeof(unimap_cp866) / sizeof(*unimap_cp866);
650 
651 table_over_7F:
652 		if (code <= 0x7F) {
653 			*res = code;
654 		} else {
655 			found = unimap_bsearch(table, code, table_size);
656 			if (found)
657 				*res = found;
658 			else
659 				return FAILURE;
660 		}
661 		break;
662 
663 	/* from here on, only map the possible characters in the ASCII range.
664 	 * to improve support here, it's a matter of building the unicode mappings.
665 	 * See <http://www.unicode.org/Public/6.0.0/ucd/Unihan.zip> */
666 	case cs_sjis:
667 	case cs_eucjp:
668 		/* we interpret 0x5C as the Yen symbol. This is not universal.
669 		 * See <http://www.w3.org/Submission/japanese-xml/#ambiguity_of_yen> */
670 		if (code >= 0x20 && code <= 0x7D) {
671 			if (code == 0x5C)
672 				return FAILURE;
673 			*res = code;
674 		} else {
675 			return FAILURE;
676 		}
677 		break;
678 
679 	case cs_big5:
680 	case cs_big5hkscs:
681 	case cs_gb2312:
682 		if (code >= 0x20 && code <= 0x7D) {
683 			*res = code;
684 		} else {
685 			return FAILURE;
686 		}
687 		break;
688 
689 	default:
690 		return FAILURE;
691 	}
692 
693 	return SUCCESS;
694 }
695 /* }}} */
696 
697 /* {{{ */
map_to_unicode(unsigned code,const enc_to_uni * table,unsigned * res)698 static inline void map_to_unicode(unsigned code, const enc_to_uni *table, unsigned *res)
699 {
700 	/* only single byte encodings are currently supported; assumed code <= 0xFF */
701 	*res = table->inner[ENT_ENC_TO_UNI_STAGE1(code)]->uni_cp[ENT_ENC_TO_UNI_STAGE2(code)];
702 }
703 /* }}} */
704 
705 /* {{{ unicode_cp_is_allowed */
unicode_cp_is_allowed(unsigned uni_cp,int document_type)706 static inline int unicode_cp_is_allowed(unsigned uni_cp, int document_type)
707 {
708 	/* XML 1.0				HTML 4.01			HTML 5
709 	 * 0x09..0x0A			0x09..0x0A			0x09..0x0A
710 	 * 0x0D					0x0D				0x0C..0x0D
711 	 * 0x0020..0xD7FF		0x20..0x7E			0x20..0x7E
712 	 *						0x00A0..0xD7FF		0x00A0..0xD7FF
713 	 * 0xE000..0xFFFD		0xE000..0x10FFFF	0xE000..0xFDCF
714 	 * 0x010000..0x10FFFF						0xFDF0..0x10FFFF (*)
715 	 *
716 	 * (*) exclude code points where ((code & 0xFFFF) >= 0xFFFE)
717 	 *
718 	 * References:
719 	 * XML 1.0:   <http://www.w3.org/TR/REC-xml/#charsets>
720 	 * HTML 4.01: <http://www.w3.org/TR/1999/PR-html40-19990824/sgml/sgmldecl.html>
721 	 * HTML 5:    <http://dev.w3.org/html5/spec/Overview.html#preprocessing-the-input-stream>
722 	 *
723 	 * Not sure this is the relevant part for HTML 5, though. I opted to
724 	 * disallow the characters that would result in a parse error when
725 	 * preprocessing of the input stream. See also section 8.1.3.
726 	 *
727 	 * It's unclear if XHTML 1.0 allows C1 characters. I'll opt to apply to
728 	 * XHTML 1.0 the same rules as for XML 1.0.
729 	 * See <http://cmsmcq.com/2007/C1.xml>.
730 	 */
731 
732 	switch (document_type) {
733 	case ENT_HTML_DOC_HTML401:
734 		return (uni_cp >= 0x20 && uni_cp <= 0x7E) ||
735 			(uni_cp == 0x0A || uni_cp == 0x09 || uni_cp == 0x0D) ||
736 			(uni_cp >= 0xA0 && uni_cp <= 0xD7FF) ||
737 			(uni_cp >= 0xE000 && uni_cp <= 0x10FFFF);
738 	case ENT_HTML_DOC_HTML5:
739 		return (uni_cp >= 0x20 && uni_cp <= 0x7E) ||
740 			(uni_cp >= 0x09 && uni_cp <= 0x0D && uni_cp != 0x0B) || /* form feed U+0C allowed */
741 			(uni_cp >= 0xA0 && uni_cp <= 0xD7FF) ||
742 			(uni_cp >= 0xE000 && uni_cp <= 0x10FFFF &&
743 				((uni_cp & 0xFFFF) < 0xFFFE) && /* last two of each plane (nonchars) disallowed */
744 				(uni_cp < 0xFDD0 || uni_cp > 0xFDEF)); /* U+FDD0-U+FDEF (nonchars) disallowed */
745 	case ENT_HTML_DOC_XHTML:
746 	case ENT_HTML_DOC_XML1:
747 		return (uni_cp >= 0x20 && uni_cp <= 0xD7FF) ||
748 			(uni_cp == 0x0A || uni_cp == 0x09 || uni_cp == 0x0D) ||
749 			(uni_cp >= 0xE000 && uni_cp <= 0x10FFFF && uni_cp != 0xFFFE && uni_cp != 0xFFFF);
750 	default:
751 		return 1;
752 	}
753 }
754 /* }}} */
755 
756 /* {{{ unicode_cp_is_allowed */
numeric_entity_is_allowed(unsigned uni_cp,int document_type)757 static inline int numeric_entity_is_allowed(unsigned uni_cp, int document_type)
758 {
759 	/* less restrictive than unicode_cp_is_allowed */
760 	switch (document_type) {
761 	case ENT_HTML_DOC_HTML401:
762 		/* all non-SGML characters (those marked with UNUSED in DESCSET) should be
763 		 * representable with numeric entities */
764 		return uni_cp <= 0x10FFFF;
765 	case ENT_HTML_DOC_HTML5:
766 		/* 8.1.4. The numeric character reference forms described above are allowed to
767 		 * reference any Unicode code point other than U+0000, U+000D, permanently
768 		 * undefined Unicode characters (noncharacters), and control characters other
769 		 * than space characters (U+0009, U+000A, U+000C and U+000D) */
770 		/* seems to allow surrogate characters, then */
771 		return (uni_cp >= 0x20 && uni_cp <= 0x7E) ||
772 			(uni_cp >= 0x09 && uni_cp <= 0x0C && uni_cp != 0x0B) || /* form feed U+0C allowed, but not U+0D */
773 			(uni_cp >= 0xA0 && uni_cp <= 0x10FFFF &&
774 				((uni_cp & 0xFFFF) < 0xFFFE) && /* last two of each plane (nonchars) disallowed */
775 				(uni_cp < 0xFDD0 || uni_cp > 0xFDEF)); /* U+FDD0-U+FDEF (nonchars) disallowed */
776 	case ENT_HTML_DOC_XHTML:
777 	case ENT_HTML_DOC_XML1:
778 		/* OTOH, XML 1.0 requires "character references to match the production for Char
779 		 * See <http://www.w3.org/TR/REC-xml/#NT-CharRef> */
780 		return unicode_cp_is_allowed(uni_cp, document_type);
781 	default:
782 		return 1;
783 	}
784 }
785 /* }}} */
786 
787 /* {{{ process_numeric_entity
788  * Auxiliary function to traverse_for_entities.
789  * On input, *buf should point to the first character after # and on output, it's the last
790  * byte read, no matter if there was success or insuccess.
791  */
process_numeric_entity(const char ** buf,unsigned * code_point)792 static inline int process_numeric_entity(const char **buf, unsigned *code_point)
793 {
794 	zend_long code_l;
795 	int hexadecimal = (**buf == 'x' || **buf == 'X'); /* TODO: XML apparently disallows "X" */
796 	char *endptr;
797 
798 	if (hexadecimal && (**buf != '\0'))
799 		(*buf)++;
800 
801 	/* strtol allows whitespace and other stuff in the beginning
802 		* we're not interested */
803 	if ((hexadecimal && !isxdigit(**buf)) ||
804 			(!hexadecimal && !isdigit(**buf))) {
805 		return FAILURE;
806 	}
807 
808 	code_l = ZEND_STRTOL(*buf, &endptr, hexadecimal ? 16 : 10);
809 	/* we're guaranteed there were valid digits, so *endptr > buf */
810 	*buf = endptr;
811 
812 	if (**buf != ';')
813 		return FAILURE;
814 
815 	/* many more are invalid, but that depends on whether it's HTML
816 	 * (and which version) or XML. */
817 	if (code_l > Z_L(0x10FFFF))
818 		return FAILURE;
819 
820 	if (code_point != NULL)
821 		*code_point = (unsigned)code_l;
822 
823 	return SUCCESS;
824 }
825 /* }}} */
826 
827 /* {{{ process_named_entity */
process_named_entity_html(const char ** buf,const char ** start,size_t * length)828 static inline int process_named_entity_html(const char **buf, const char **start, size_t *length)
829 {
830 	*start = *buf;
831 
832 	/* "&" is represented by a 0x26 in all supported encodings. That means
833 	 * the byte after represents a character or is the leading byte of an
834 	 * sequence of 8-bit code units. If in the ranges below, it represents
835 	 * necessarily a alpha character because none of the supported encodings
836 	 * has an overlap with ASCII in the leading byte (only on the second one) */
837 	while ((**buf >= 'a' && **buf <= 'z') ||
838 			(**buf >= 'A' && **buf <= 'Z') ||
839 			(**buf >= '0' && **buf <= '9')) {
840 		(*buf)++;
841 	}
842 
843 	if (**buf != ';')
844 		return FAILURE;
845 
846 	/* cast to size_t OK as the quantity is always non-negative */
847 	*length = *buf - *start;
848 
849 	if (*length == 0)
850 		return FAILURE;
851 
852 	return SUCCESS;
853 }
854 /* }}} */
855 
856 /* {{{ resolve_named_entity_html */
resolve_named_entity_html(const char * start,size_t length,const entity_ht * ht,unsigned * uni_cp1,unsigned * uni_cp2)857 static inline int resolve_named_entity_html(const char *start, size_t length, const entity_ht *ht, unsigned *uni_cp1, unsigned *uni_cp2)
858 {
859 	const entity_cp_map *s;
860 	zend_ulong hash = zend_inline_hash_func(start, length);
861 
862 	s = ht->buckets[hash % ht->num_elems];
863 	while (s->entity) {
864 		if (s->entity_len == length) {
865 			if (memcmp(start, s->entity, length) == 0) {
866 				*uni_cp1 = s->codepoint1;
867 				*uni_cp2 = s->codepoint2;
868 				return SUCCESS;
869 			}
870 		}
871 		s++;
872 	}
873 	return FAILURE;
874 }
875 /* }}} */
876 
write_octet_sequence(unsigned char * buf,enum entity_charset charset,unsigned code)877 static inline size_t write_octet_sequence(unsigned char *buf, enum entity_charset charset, unsigned code) {
878 	/* code is not necessarily a unicode code point */
879 	switch (charset) {
880 	case cs_utf_8:
881 		return php_utf32_utf8(buf, code);
882 
883 	case cs_8859_1:
884 	case cs_cp1252:
885 	case cs_8859_15:
886 	case cs_koi8r:
887 	case cs_cp1251:
888 	case cs_8859_5:
889 	case cs_cp866:
890 	case cs_macroman:
891 		/* single byte stuff */
892 		*buf = code;
893 		return 1;
894 
895 	case cs_big5:
896 	case cs_big5hkscs:
897 	case cs_sjis:
898 	case cs_gb2312:
899 		/* we don't have complete unicode mappings for these yet in entity_decode,
900 		 * and we opt to pass through the octet sequences for these in htmlentities
901 		 * instead of converting to an int and then converting back. */
902 #if 0
903 		return php_mb2_int_to_char(buf, code);
904 #else
905 #if ZEND_DEBUG
906 		assert(code <= 0xFFU);
907 #endif
908 		*buf = code;
909 		return 1;
910 #endif
911 
912 	case cs_eucjp:
913 #if 0 /* idem */
914 		return php_mb2_int_to_char(buf, code);
915 #else
916 #if ZEND_DEBUG
917 		assert(code <= 0xFFU);
918 #endif
919 		*buf = code;
920 		return 1;
921 #endif
922 
923 	default:
924 		assert(0);
925 		return 0;
926 	}
927 }
928 
929 /* {{{ traverse_for_entities
930  * Auxiliary function to php_unescape_html_entities().
931  * - The argument "all" determines if all numeric entities are decode or only those
932  *   that correspond to quotes (depending on quote_style).
933  */
934 /* maximum expansion (factor 1.2) for HTML 5 with &nGt; and &nLt; */
935 /* +2 is 1 because of rest (probably unnecessary), 1 because of terminating 0 */
936 #define TRAVERSE_FOR_ENTITIES_EXPAND_SIZE(oldlen) ((oldlen) + (oldlen) / 5 + 2)
traverse_for_entities(const char * old,size_t oldlen,zend_string * ret,int all,int flags,const entity_ht * inv_map,enum entity_charset charset)937 static void traverse_for_entities(
938 	const char *old,
939 	size_t oldlen,
940 	zend_string *ret, /* should have allocated TRAVERSE_FOR_ENTITIES_EXPAND_SIZE(olden) */
941 	int all,
942 	int flags,
943 	const entity_ht *inv_map,
944 	enum entity_charset charset)
945 {
946 	const char *p,
947 			   *lim;
948 	char	   *q;
949 	int doctype = flags & ENT_HTML_DOC_TYPE_MASK;
950 
951 	lim = old + oldlen; /* terminator address */
952 	assert(*lim == '\0');
953 
954 	for (p = old, q = ZSTR_VAL(ret); p < lim;) {
955 		unsigned code, code2 = 0;
956 		const char *next = NULL; /* when set, next > p, otherwise possible inf loop */
957 
958 		/* Shift JIS, Big5 and HKSCS use multi-byte encodings where an
959 		 * ASCII range byte can be part of a multi-byte sequence.
960 		 * However, they start at 0x40, therefore if we find a 0x26 byte,
961 		 * we're sure it represents the '&' character. */
962 
963 		/* assumes there are no single-char entities */
964 		if (p[0] != '&' || (p + 3 >= lim)) {
965 			*(q++) = *(p++);
966 			continue;
967 		}
968 
969 		/* now p[3] is surely valid and is no terminator */
970 
971 		/* numerical entity */
972 		if (p[1] == '#') {
973 			next = &p[2];
974 			if (process_numeric_entity(&next, &code) == FAILURE)
975 				goto invalid_code;
976 
977 			/* If we're in htmlspecialchars_decode, we're only decoding entities
978 			 * that represent &, <, >, " and '. Is this one of them? */
979 			if (!all && (code > 63U ||
980 					stage3_table_be_apos_00000[code].data.ent.entity == NULL))
981 				goto invalid_code;
982 
983 			/* are we allowed to decode this entity in this document type?
984 			 * HTML 5 is the only that has a character that cannot be used in
985 			 * a numeric entity but is allowed literally (U+000D). The
986 			 * unoptimized version would be ... || !numeric_entity_is_allowed(code) */
987 			if (!unicode_cp_is_allowed(code, doctype) ||
988 					(doctype == ENT_HTML_DOC_HTML5 && code == 0x0D))
989 				goto invalid_code;
990 		} else {
991 			const char *start;
992 			size_t ent_len;
993 
994 			next = &p[1];
995 			start = next;
996 
997 			if (process_named_entity_html(&next, &start, &ent_len) == FAILURE)
998 				goto invalid_code;
999 
1000 			if (resolve_named_entity_html(start, ent_len, inv_map, &code, &code2) == FAILURE) {
1001 				if (doctype == ENT_HTML_DOC_XHTML && ent_len == 4 && start[0] == 'a'
1002 							&& start[1] == 'p' && start[2] == 'o' && start[3] == 's') {
1003 					/* uses html4 inv_map, which doesn't include apos;. This is a
1004 					 * hack to support it */
1005 					code = (unsigned) '\'';
1006 				} else {
1007 					goto invalid_code;
1008 				}
1009 			}
1010 		}
1011 
1012 		assert(*next == ';');
1013 
1014 		if (((code == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1015 				(code == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE)))
1016 				/* && code2 == '\0' always true for current maps */)
1017 			goto invalid_code;
1018 
1019 		/* UTF-8 doesn't need mapping (ISO-8859-1 doesn't either, but
1020 		 * the call is needed to ensure the codepoint <= U+00FF)  */
1021 		if (charset != cs_utf_8) {
1022 			/* replace unicode code point */
1023 			if (map_from_unicode(code, charset, &code) == FAILURE || code2 != 0)
1024 				goto invalid_code; /* not representable in target charset */
1025 		}
1026 
1027 		q += write_octet_sequence((unsigned char*)q, charset, code);
1028 		if (code2) {
1029 			q += write_octet_sequence((unsigned char*)q, charset, code2);
1030 		}
1031 
1032 		/* jump over the valid entity; may go beyond size of buffer; np */
1033 		p = next + 1;
1034 		continue;
1035 
1036 invalid_code:
1037 		for (; p < next; p++) {
1038 			*(q++) = *p;
1039 		}
1040 	}
1041 
1042 	*q = '\0';
1043 	ZSTR_LEN(ret) = (size_t)(q - ZSTR_VAL(ret));
1044 }
1045 /* }}} */
1046 
1047 /* {{{ unescape_inverse_map */
unescape_inverse_map(int all,int flags)1048 static const entity_ht *unescape_inverse_map(int all, int flags)
1049 {
1050 	int document_type = flags & ENT_HTML_DOC_TYPE_MASK;
1051 
1052 	if (all) {
1053 		switch (document_type) {
1054 		case ENT_HTML_DOC_HTML401:
1055 		case ENT_HTML_DOC_XHTML: /* but watch out for &apos;...*/
1056 			return &ent_ht_html4;
1057 		case ENT_HTML_DOC_HTML5:
1058 			return &ent_ht_html5;
1059 		default:
1060 			return &ent_ht_be_apos;
1061 		}
1062 	} else {
1063 		switch (document_type) {
1064 		case ENT_HTML_DOC_HTML401:
1065 			return &ent_ht_be_noapos;
1066 		default:
1067 			return &ent_ht_be_apos;
1068 		}
1069 	}
1070 }
1071 /* }}} */
1072 
1073 /* {{{ determine_entity_table
1074  * Entity table to use. Note that entity tables are defined in terms of
1075  * unicode code points */
determine_entity_table(int all,int doctype)1076 static entity_table_opt determine_entity_table(int all, int doctype)
1077 {
1078 	entity_table_opt retval = {NULL};
1079 
1080 	assert(!(doctype == ENT_HTML_DOC_XML1 && all));
1081 
1082 	if (all) {
1083 		retval.ms_table = (doctype == ENT_HTML_DOC_HTML5) ?
1084 			entity_ms_table_html5 : entity_ms_table_html4;
1085 	} else {
1086 		retval.table = (doctype == ENT_HTML_DOC_HTML401) ?
1087 			stage3_table_be_noapos_00000 : stage3_table_be_apos_00000;
1088 	}
1089 	return retval;
1090 }
1091 /* }}} */
1092 
1093 /* {{{ php_unescape_html_entities
1094  * The parameter "all" should be true to decode all possible entities, false to decode
1095  * only the basic ones, i.e., those in basic_entities_ex + the numeric entities
1096  * that correspond to quotes.
1097  */
php_unescape_html_entities(zend_string * str,int all,int flags,char * hint_charset)1098 PHPAPI zend_string *php_unescape_html_entities(zend_string *str, int all, int flags, char *hint_charset)
1099 {
1100 	zend_string *ret;
1101 	enum entity_charset charset;
1102 	const entity_ht *inverse_map;
1103 	size_t new_size;
1104 
1105 	if (!memchr(ZSTR_VAL(str), '&', ZSTR_LEN(str))) {
1106 		return zend_string_copy(str);
1107 	}
1108 
1109 	if (all) {
1110 		charset = determine_charset(hint_charset);
1111 	} else {
1112 		charset = cs_8859_1; /* charset shouldn't matter, use ISO-8859-1 for performance */
1113 	}
1114 
1115 	/* don't use LIMIT_ALL! */
1116 
1117 	new_size = TRAVERSE_FOR_ENTITIES_EXPAND_SIZE(ZSTR_LEN(str));
1118 	if (ZSTR_LEN(str) > new_size) {
1119 		/* overflow, refuse to do anything */
1120 		return zend_string_copy(str);
1121 	}
1122 
1123 	ret = zend_string_alloc(new_size, 0);
1124 
1125 	inverse_map = unescape_inverse_map(all, flags);
1126 
1127 	/* replace numeric entities */
1128 	traverse_for_entities(ZSTR_VAL(str), ZSTR_LEN(str), ret, all, flags, inverse_map, charset);
1129 
1130 	return ret;
1131 }
1132 /* }}} */
1133 
php_escape_html_entities(unsigned char * old,size_t oldlen,int all,int flags,char * hint_charset)1134 PHPAPI zend_string *php_escape_html_entities(unsigned char *old, size_t oldlen, int all, int flags, char *hint_charset)
1135 {
1136 	return php_escape_html_entities_ex(old, oldlen, all, flags, hint_charset, 1);
1137 }
1138 
1139 /* {{{ find_entity_for_char */
find_entity_for_char(unsigned int k,enum entity_charset charset,const entity_stage1_row * table,const unsigned char ** entity,size_t * entity_len,unsigned char * old,size_t oldlen,size_t * cursor)1140 static inline void find_entity_for_char(
1141 	unsigned int k,
1142 	enum entity_charset charset,
1143 	const entity_stage1_row *table,
1144 	const unsigned char **entity,
1145 	size_t *entity_len,
1146 	unsigned char *old,
1147 	size_t oldlen,
1148 	size_t *cursor)
1149 {
1150 	unsigned stage1_idx = ENT_STAGE1_INDEX(k);
1151 	const entity_stage3_row *c;
1152 
1153 	if (stage1_idx > 0x1D) {
1154 		*entity     = NULL;
1155 		*entity_len = 0;
1156 		return;
1157 	}
1158 
1159 	c = &table[stage1_idx][ENT_STAGE2_INDEX(k)][ENT_STAGE3_INDEX(k)];
1160 
1161 	if (!c->ambiguous) {
1162 		*entity     = (const unsigned char *)c->data.ent.entity;
1163 		*entity_len = c->data.ent.entity_len;
1164 	} else {
1165 		/* peek at next char */
1166 		size_t	 cursor_before	= *cursor;
1167 		int		 status			= SUCCESS;
1168 		unsigned next_char;
1169 
1170 		if (!(*cursor < oldlen))
1171 			goto no_suitable_2nd;
1172 
1173 		next_char = get_next_char(charset, old, oldlen, cursor, &status);
1174 
1175 		if (status == FAILURE)
1176 			goto no_suitable_2nd;
1177 
1178 		{
1179 			const entity_multicodepoint_row *s, *e;
1180 
1181 			s = &c->data.multicodepoint_table[1];
1182 			e = s - 1 + c->data.multicodepoint_table[0].leading_entry.size;
1183 			/* we could do a binary search but it's not worth it since we have
1184 			 * at most two entries... */
1185 			for ( ; s <= e; s++) {
1186 				if (s->normal_entry.second_cp == next_char) {
1187 					*entity     = (const unsigned char *) s->normal_entry.entity;
1188 					*entity_len = s->normal_entry.entity_len;
1189 					return;
1190 				}
1191 			}
1192 		}
1193 no_suitable_2nd:
1194 		*cursor = cursor_before;
1195 		*entity = (const unsigned char *)
1196 			c->data.multicodepoint_table[0].leading_entry.default_entity;
1197 		*entity_len = c->data.multicodepoint_table[0].leading_entry.default_entity_len;
1198 	}
1199 }
1200 /* }}} */
1201 
1202 /* {{{ find_entity_for_char_basic */
find_entity_for_char_basic(unsigned int k,const entity_stage3_row * table,const unsigned char ** entity,size_t * entity_len)1203 static inline void find_entity_for_char_basic(
1204 	unsigned int k,
1205 	const entity_stage3_row *table,
1206 	const unsigned char **entity,
1207 	size_t *entity_len)
1208 {
1209 	if (k >= 64U) {
1210 		*entity     = NULL;
1211 		*entity_len = 0;
1212 		return;
1213 	}
1214 
1215 	*entity     = (const unsigned char *) table[k].data.ent.entity;
1216 	*entity_len = table[k].data.ent.entity_len;
1217 }
1218 /* }}} */
1219 
1220 /* {{{ php_escape_html_entities
1221  */
php_escape_html_entities_ex(unsigned char * old,size_t oldlen,int all,int flags,char * hint_charset,zend_bool double_encode)1222 PHPAPI zend_string *php_escape_html_entities_ex(unsigned char *old, size_t oldlen, int all, int flags, char *hint_charset, zend_bool double_encode)
1223 {
1224 	size_t cursor, maxlen, len;
1225 	zend_string *replaced;
1226 	enum entity_charset charset = determine_charset(hint_charset);
1227 	int doctype = flags & ENT_HTML_DOC_TYPE_MASK;
1228 	entity_table_opt entity_table;
1229 	const enc_to_uni *to_uni_table = NULL;
1230 	const entity_ht *inv_map = NULL; /* used for !double_encode */
1231 	/* only used if flags includes ENT_HTML_IGNORE_ERRORS or ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS */
1232 	const unsigned char *replacement = NULL;
1233 	size_t replacement_len = 0;
1234 
1235 	if (all) { /* replace with all named entities */
1236 		if (CHARSET_PARTIAL_SUPPORT(charset)) {
1237 			php_error_docref0(NULL, E_STRICT, "Only basic entities "
1238 				"substitution is supported for multi-byte encodings other than UTF-8; "
1239 				"functionality is equivalent to htmlspecialchars");
1240 		}
1241 		LIMIT_ALL(all, doctype, charset);
1242 	}
1243 	entity_table = determine_entity_table(all, doctype);
1244 	if (all && !CHARSET_UNICODE_COMPAT(charset)) {
1245 		to_uni_table = enc_to_uni_index[charset];
1246 	}
1247 
1248 	if (!double_encode) {
1249 		/* first arg is 1 because we want to identify valid named entities
1250 		 * even if we are only encoding the basic ones */
1251 		inv_map = unescape_inverse_map(1, flags);
1252 	}
1253 
1254 	if (flags & (ENT_HTML_SUBSTITUTE_ERRORS | ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS)) {
1255 		if (charset == cs_utf_8) {
1256 			replacement = (const unsigned char*)"\xEF\xBF\xBD";
1257 			replacement_len = sizeof("\xEF\xBF\xBD") - 1;
1258 		} else {
1259 			replacement = (const unsigned char*)"&#xFFFD;";
1260 			replacement_len = sizeof("&#xFFFD;") - 1;
1261 		}
1262 	}
1263 
1264 	/* initial estimate */
1265 	if (oldlen < 64) {
1266 		maxlen = 128;
1267 	} else {
1268 		maxlen = zend_safe_addmult(oldlen, 2, 0, "html_entities");
1269 	}
1270 
1271 	replaced = zend_string_alloc(maxlen, 0);
1272 	len = 0;
1273 	cursor = 0;
1274 	while (cursor < oldlen) {
1275 		const unsigned char *mbsequence = NULL;
1276 		size_t mbseqlen					= 0,
1277 		       cursor_before			= cursor;
1278 		int status						= SUCCESS;
1279 		unsigned int this_char			= get_next_char(charset, old, oldlen, &cursor, &status);
1280 
1281 		/* guarantee we have at least 40 bytes to write.
1282 		 * In HTML5, entities may take up to 33 bytes */
1283 		if (len > maxlen - 40) { /* maxlen can never be smaller than 128 */
1284 			replaced = zend_string_safe_realloc(replaced, maxlen, 1, 128, 0);
1285 			maxlen += 128;
1286 		}
1287 
1288 		if (status == FAILURE) {
1289 			/* invalid MB sequence */
1290 			if (flags & ENT_HTML_IGNORE_ERRORS) {
1291 				continue;
1292 			} else if (flags & ENT_HTML_SUBSTITUTE_ERRORS) {
1293 				memcpy(&ZSTR_VAL(replaced)[len], replacement, replacement_len);
1294 				len += replacement_len;
1295 				continue;
1296 			} else {
1297 				zend_string_free(replaced);
1298 				return ZSTR_EMPTY_ALLOC();
1299 			}
1300 		} else { /* SUCCESS */
1301 			mbsequence = &old[cursor_before];
1302 			mbseqlen = cursor - cursor_before;
1303 		}
1304 
1305 		if (this_char != '&') { /* no entity on this position */
1306 			const unsigned char *rep	= NULL;
1307 			size_t				rep_len	= 0;
1308 
1309 			if (((this_char == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1310 					(this_char == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1311 				goto pass_char_through;
1312 
1313 			if (all) { /* false that CHARSET_PARTIAL_SUPPORT(charset) */
1314 				if (to_uni_table != NULL) {
1315 					/* !CHARSET_UNICODE_COMPAT therefore not UTF-8; since UTF-8
1316 					 * is the only multibyte encoding with !CHARSET_PARTIAL_SUPPORT,
1317 					 * we're using a single byte encoding */
1318 					map_to_unicode(this_char, to_uni_table, &this_char);
1319 					if (this_char == 0xFFFF) /* no mapping; pass through */
1320 						goto pass_char_through;
1321 				}
1322 				/* the cursor may advance */
1323 				find_entity_for_char(this_char, charset, entity_table.ms_table, &rep,
1324 					&rep_len, old, oldlen, &cursor);
1325 			} else {
1326 				find_entity_for_char_basic(this_char, entity_table.table, &rep, &rep_len);
1327 			}
1328 
1329 			if (rep != NULL) {
1330 				ZSTR_VAL(replaced)[len++] = '&';
1331 				memcpy(&ZSTR_VAL(replaced)[len], rep, rep_len);
1332 				len += rep_len;
1333 				ZSTR_VAL(replaced)[len++] = ';';
1334 			} else {
1335 				/* we did not find an entity for this char.
1336 				 * check for its validity, if its valid pass it unchanged */
1337 				if (flags & ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS) {
1338 					if (CHARSET_UNICODE_COMPAT(charset)) {
1339 						if (!unicode_cp_is_allowed(this_char, doctype)) {
1340 							mbsequence = replacement;
1341 							mbseqlen = replacement_len;
1342 						}
1343 					} else if (to_uni_table) {
1344 						if (!all) /* otherwise we already did this */
1345 							map_to_unicode(this_char, to_uni_table, &this_char);
1346 						if (!unicode_cp_is_allowed(this_char, doctype)) {
1347 							mbsequence = replacement;
1348 							mbseqlen = replacement_len;
1349 						}
1350 					} else {
1351 						/* not a unicode code point, unless, coincidentally, it's in
1352 						 * the 0x20..0x7D range (except 0x5C in sjis). We know nothing
1353 						 * about other code points, because we have no tables. Since
1354 						 * Unicode code points in that range are not disallowed in any
1355 						 * document type, we could do nothing. However, conversion
1356 						 * tables frequently map 0x00-0x1F to the respective C0 code
1357 						 * points. Let's play it safe and admit that's the case */
1358 						if (this_char <= 0x7D &&
1359 								!unicode_cp_is_allowed(this_char, doctype)) {
1360 							mbsequence = replacement;
1361 							mbseqlen = replacement_len;
1362 						}
1363 					}
1364 				}
1365 pass_char_through:
1366 				if (mbseqlen > 1) {
1367 					memcpy(ZSTR_VAL(replaced) + len, mbsequence, mbseqlen);
1368 					len += mbseqlen;
1369 				} else {
1370 					ZSTR_VAL(replaced)[len++] = mbsequence[0];
1371 				}
1372 			}
1373 		} else { /* this_char == '&' */
1374 			if (double_encode) {
1375 encode_amp:
1376 				memcpy(&ZSTR_VAL(replaced)[len], "&amp;", sizeof("&amp;") - 1);
1377 				len += sizeof("&amp;") - 1;
1378 			} else { /* no double encode */
1379 				/* check if entity is valid */
1380 				size_t ent_len; /* not counting & or ; */
1381 				/* peek at next char */
1382 				if (old[cursor] == '#') { /* numeric entity */
1383 					unsigned code_point;
1384 					int valid;
1385 					char *pos = (char*)&old[cursor+1];
1386 					valid = process_numeric_entity((const char **)&pos, &code_point);
1387 					if (valid == FAILURE)
1388 						goto encode_amp;
1389 					if (flags & ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS) {
1390 						if (!numeric_entity_is_allowed(code_point, doctype))
1391 							goto encode_amp;
1392 					}
1393 					ent_len = pos - (char*)&old[cursor];
1394 				} else { /* named entity */
1395 					/* check for vality of named entity */
1396 					const char *start = (const char *) &old[cursor],
1397 							   *next = start;
1398 					unsigned   dummy1, dummy2;
1399 
1400 					if (process_named_entity_html(&next, &start, &ent_len) == FAILURE)
1401 						goto encode_amp;
1402 					if (resolve_named_entity_html(start, ent_len, inv_map, &dummy1, &dummy2) == FAILURE) {
1403 						if (!(doctype == ENT_HTML_DOC_XHTML && ent_len == 4 && start[0] == 'a'
1404 									&& start[1] == 'p' && start[2] == 'o' && start[3] == 's')) {
1405 							/* uses html4 inv_map, which doesn't include apos;. This is a
1406 							 * hack to support it */
1407 							goto encode_amp;
1408 						}
1409 					}
1410 				}
1411 				/* checks passed; copy entity to result */
1412 				/* entity size is unbounded, we may need more memory */
1413 				/* at this point maxlen - len >= 40 */
1414 				if (maxlen - len < ent_len + 2 /* & and ; */) {
1415 					/* ent_len < oldlen, which is certainly <= SIZE_MAX/2 */
1416 					replaced = zend_string_safe_realloc(replaced, maxlen, 1, ent_len + 128, 0);
1417 					maxlen += ent_len + 128;
1418 				}
1419 				ZSTR_VAL(replaced)[len++] = '&';
1420 				memcpy(&ZSTR_VAL(replaced)[len], &old[cursor], ent_len);
1421 				len += ent_len;
1422 				ZSTR_VAL(replaced)[len++] = ';';
1423 				cursor += ent_len + 1;
1424 			}
1425 		}
1426 	}
1427 	ZSTR_VAL(replaced)[len] = '\0';
1428 	ZSTR_LEN(replaced) = len;
1429 
1430 	return replaced;
1431 }
1432 /* }}} */
1433 
1434 /* {{{ php_html_entities
1435  */
php_html_entities(INTERNAL_FUNCTION_PARAMETERS,int all)1436 static void php_html_entities(INTERNAL_FUNCTION_PARAMETERS, int all)
1437 {
1438 	zend_string *str, *hint_charset = NULL;
1439 	char *default_charset;
1440 	zend_long flags = ENT_COMPAT;
1441 	zend_string *replaced;
1442 	zend_bool double_encode = 1;
1443 
1444 	ZEND_PARSE_PARAMETERS_START(1, 4)
1445 		Z_PARAM_STR(str)
1446 		Z_PARAM_OPTIONAL
1447 		Z_PARAM_LONG(flags)
1448 		Z_PARAM_STR_EX(hint_charset, 1, 0)
1449 		Z_PARAM_BOOL(double_encode);
1450 	ZEND_PARSE_PARAMETERS_END();
1451 
1452 	if (!hint_charset) {
1453 		default_charset = get_default_charset();
1454 	}
1455 	replaced = php_escape_html_entities_ex((unsigned char*)ZSTR_VAL(str), ZSTR_LEN(str), all, (int) flags, (hint_charset ? ZSTR_VAL(hint_charset) : default_charset), double_encode);
1456 	RETVAL_STR(replaced);
1457 }
1458 /* }}} */
1459 
1460 #define HTML_SPECIALCHARS 	0
1461 #define HTML_ENTITIES	 	1
1462 
1463 /* {{{ register_html_constants
1464  */
register_html_constants(INIT_FUNC_ARGS)1465 void register_html_constants(INIT_FUNC_ARGS)
1466 {
1467 	REGISTER_LONG_CONSTANT("HTML_SPECIALCHARS", HTML_SPECIALCHARS, CONST_PERSISTENT|CONST_CS);
1468 	REGISTER_LONG_CONSTANT("HTML_ENTITIES", HTML_ENTITIES, CONST_PERSISTENT|CONST_CS);
1469 	REGISTER_LONG_CONSTANT("ENT_COMPAT", ENT_COMPAT, CONST_PERSISTENT|CONST_CS);
1470 	REGISTER_LONG_CONSTANT("ENT_QUOTES", ENT_QUOTES, CONST_PERSISTENT|CONST_CS);
1471 	REGISTER_LONG_CONSTANT("ENT_NOQUOTES", ENT_NOQUOTES, CONST_PERSISTENT|CONST_CS);
1472 	REGISTER_LONG_CONSTANT("ENT_IGNORE", ENT_IGNORE, CONST_PERSISTENT|CONST_CS);
1473 	REGISTER_LONG_CONSTANT("ENT_SUBSTITUTE", ENT_SUBSTITUTE, CONST_PERSISTENT|CONST_CS);
1474 	REGISTER_LONG_CONSTANT("ENT_DISALLOWED", ENT_DISALLOWED, CONST_PERSISTENT|CONST_CS);
1475 	REGISTER_LONG_CONSTANT("ENT_HTML401", ENT_HTML401, CONST_PERSISTENT|CONST_CS);
1476 	REGISTER_LONG_CONSTANT("ENT_XML1", ENT_XML1, CONST_PERSISTENT|CONST_CS);
1477 	REGISTER_LONG_CONSTANT("ENT_XHTML", ENT_XHTML, CONST_PERSISTENT|CONST_CS);
1478 	REGISTER_LONG_CONSTANT("ENT_HTML5", ENT_HTML5, CONST_PERSISTENT|CONST_CS);
1479 }
1480 /* }}} */
1481 
1482 /* {{{ proto string htmlspecialchars(string string [, int quote_style[, string encoding[, bool double_encode]]])
1483    Convert special characters to HTML entities */
PHP_FUNCTION(htmlspecialchars)1484 PHP_FUNCTION(htmlspecialchars)
1485 {
1486 	php_html_entities(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
1487 }
1488 /* }}} */
1489 
1490 /* {{{ proto string htmlspecialchars_decode(string string [, int quote_style])
1491    Convert special HTML entities back to characters */
PHP_FUNCTION(htmlspecialchars_decode)1492 PHP_FUNCTION(htmlspecialchars_decode)
1493 {
1494 	zend_string *str;
1495 	zend_long quote_style = ENT_COMPAT;
1496 	zend_string *replaced;
1497 
1498 	ZEND_PARSE_PARAMETERS_START(1, 2)
1499 		Z_PARAM_STR(str)
1500 		Z_PARAM_OPTIONAL
1501 		Z_PARAM_LONG(quote_style)
1502 	ZEND_PARSE_PARAMETERS_END();
1503 
1504 	replaced = php_unescape_html_entities(str, 0 /*!all*/, (int)quote_style, NULL);
1505 	if (replaced) {
1506 		RETURN_STR(replaced);
1507 	}
1508 	RETURN_FALSE;
1509 }
1510 /* }}} */
1511 
1512 /* {{{ proto string html_entity_decode(string string [, int quote_style][, string encoding])
1513    Convert all HTML entities to their applicable characters */
PHP_FUNCTION(html_entity_decode)1514 PHP_FUNCTION(html_entity_decode)
1515 {
1516 	zend_string *str, *hint_charset = NULL;
1517 	char *default_charset;
1518 	zend_long quote_style = ENT_COMPAT;
1519 	zend_string *replaced;
1520 
1521 	ZEND_PARSE_PARAMETERS_START(1, 3)
1522 		Z_PARAM_STR(str)
1523 		Z_PARAM_OPTIONAL
1524 		Z_PARAM_LONG(quote_style)
1525 		Z_PARAM_STR(hint_charset)
1526 	ZEND_PARSE_PARAMETERS_END();
1527 
1528 	if (!hint_charset) {
1529 		default_charset = get_default_charset();
1530 	}
1531 	replaced = php_unescape_html_entities(str, 1 /*all*/, (int)quote_style, (hint_charset ? ZSTR_VAL(hint_charset) : default_charset));
1532 
1533 	if (replaced) {
1534 		RETURN_STR(replaced);
1535 	}
1536 	RETURN_FALSE;
1537 }
1538 /* }}} */
1539 
1540 
1541 /* {{{ proto string htmlentities(string string [, int quote_style[, string encoding[, bool double_encode]]])
1542    Convert all applicable characters to HTML entities */
PHP_FUNCTION(htmlentities)1543 PHP_FUNCTION(htmlentities)
1544 {
1545 	php_html_entities(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
1546 }
1547 /* }}} */
1548 
1549 /* {{{ write_s3row_data */
write_s3row_data(const entity_stage3_row * r,unsigned orig_cp,enum entity_charset charset,zval * arr)1550 static inline void write_s3row_data(
1551 	const entity_stage3_row *r,
1552 	unsigned orig_cp,
1553 	enum entity_charset charset,
1554 	zval *arr)
1555 {
1556 	char key[9] = ""; /* two unicode code points in UTF-8 */
1557 	char entity[LONGEST_ENTITY_LENGTH + 2] = {'&'};
1558 	size_t written_k1;
1559 
1560 	written_k1 = write_octet_sequence((unsigned char*)key, charset, orig_cp);
1561 
1562 	if (!r->ambiguous) {
1563 		size_t l = r->data.ent.entity_len;
1564 		memcpy(&entity[1], r->data.ent.entity, l);
1565 		entity[l + 1] = ';';
1566 		add_assoc_stringl_ex(arr, key, written_k1, entity, l + 2);
1567 	} else {
1568 		unsigned i,
1569 			     num_entries;
1570 		const entity_multicodepoint_row *mcpr = r->data.multicodepoint_table;
1571 
1572 		if (mcpr[0].leading_entry.default_entity != NULL) {
1573 			size_t l = mcpr[0].leading_entry.default_entity_len;
1574 			memcpy(&entity[1], mcpr[0].leading_entry.default_entity, l);
1575 			entity[l + 1] = ';';
1576 			add_assoc_stringl_ex(arr, key, written_k1, entity, l + 2);
1577 		}
1578 		num_entries = mcpr[0].leading_entry.size;
1579 		for (i = 1; i <= num_entries; i++) {
1580 			size_t   l,
1581 				     written_k2;
1582 			unsigned uni_cp,
1583 					 spe_cp;
1584 
1585 			uni_cp = mcpr[i].normal_entry.second_cp;
1586 			l = mcpr[i].normal_entry.entity_len;
1587 
1588 			if (!CHARSET_UNICODE_COMPAT(charset)) {
1589 				if (map_from_unicode(uni_cp, charset, &spe_cp) == FAILURE)
1590 					continue; /* non representable in this charset */
1591 			} else {
1592 				spe_cp = uni_cp;
1593 			}
1594 
1595 			written_k2 = write_octet_sequence((unsigned char*)&key[written_k1], charset, spe_cp);
1596 			memcpy(&entity[1], mcpr[i].normal_entry.entity, l);
1597 			entity[l + 1] = ';';
1598 			add_assoc_stringl_ex(arr, key, written_k1 + written_k2, entity, l + 2);
1599 		}
1600 	}
1601 }
1602 /* }}} */
1603 
1604 /* {{{ proto array get_html_translation_table([int table [, int flags [, string encoding]]])
1605    Returns the internal translation table used by htmlspecialchars and htmlentities */
PHP_FUNCTION(get_html_translation_table)1606 PHP_FUNCTION(get_html_translation_table)
1607 {
1608 	zend_long all = HTML_SPECIALCHARS,
1609 		 flags = ENT_COMPAT;
1610 	int doctype;
1611 	entity_table_opt entity_table;
1612 	const enc_to_uni *to_uni_table = NULL;
1613 	char *charset_hint = NULL;
1614 	size_t charset_hint_len;
1615 	enum entity_charset charset;
1616 
1617 	/* in this function we have to jump through some loops because we're
1618 	 * getting the translated table from data structures that are optimized for
1619 	 * random access, not traversal */
1620 
1621 	ZEND_PARSE_PARAMETERS_START(0, 3)
1622 		Z_PARAM_OPTIONAL
1623 		Z_PARAM_LONG(all)
1624 		Z_PARAM_LONG(flags)
1625 		Z_PARAM_STRING(charset_hint, charset_hint_len)
1626 	ZEND_PARSE_PARAMETERS_END();
1627 
1628 	charset = determine_charset(charset_hint);
1629 	doctype = flags & ENT_HTML_DOC_TYPE_MASK;
1630 	LIMIT_ALL(all, doctype, charset);
1631 
1632 	array_init(return_value);
1633 
1634 	entity_table = determine_entity_table((int)all, doctype);
1635 	if (all && !CHARSET_UNICODE_COMPAT(charset)) {
1636 		to_uni_table = enc_to_uni_index[charset];
1637 	}
1638 
1639 	if (all) { /* HTML_ENTITIES (actually, any non-zero value for 1st param) */
1640 		const entity_stage1_row *ms_table = entity_table.ms_table;
1641 
1642 		if (CHARSET_UNICODE_COMPAT(charset)) {
1643 			unsigned i, j, k,
1644 					 max_i, max_j, max_k;
1645 			/* no mapping to unicode required */
1646 			if (CHARSET_SINGLE_BYTE(charset)) { /* ISO-8859-1 */
1647 				max_i = 1; max_j = 4; max_k = 64;
1648 			} else {
1649 				max_i = 0x1E; max_j = 64; max_k = 64;
1650 			}
1651 
1652 			for (i = 0; i < max_i; i++) {
1653 				if (ms_table[i] == empty_stage2_table)
1654 					continue;
1655 				for (j = 0; j < max_j; j++) {
1656 					if (ms_table[i][j] == empty_stage3_table)
1657 						continue;
1658 					for (k = 0; k < max_k; k++) {
1659 						const entity_stage3_row *r = &ms_table[i][j][k];
1660 						unsigned code;
1661 
1662 						if (r->data.ent.entity == NULL)
1663 							continue;
1664 
1665 						code = ENT_CODE_POINT_FROM_STAGES(i, j, k);
1666 						if (((code == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1667 								(code == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1668 							continue;
1669 						write_s3row_data(r, code, charset, return_value);
1670 					}
1671 				}
1672 			}
1673 		} else {
1674 			/* we have to iterate through the set of code points for this
1675 			 * encoding and map them to unicode code points */
1676 			unsigned i;
1677 			for (i = 0; i <= 0xFF; i++) {
1678 				const entity_stage3_row *r;
1679 				unsigned uni_cp;
1680 
1681 				/* can be done before mapping, they're invariant */
1682 				if (((i == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1683 						(i == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1684 					continue;
1685 
1686 				map_to_unicode(i, to_uni_table, &uni_cp);
1687 				r = &ms_table[ENT_STAGE1_INDEX(uni_cp)][ENT_STAGE2_INDEX(uni_cp)][ENT_STAGE3_INDEX(uni_cp)];
1688 				if (r->data.ent.entity == NULL)
1689 					continue;
1690 
1691 				write_s3row_data(r, i, charset, return_value);
1692 			}
1693 		}
1694 	} else {
1695 		/* we could use sizeof(stage3_table_be_apos_00000) as well */
1696 		unsigned	  j,
1697 					  numelems = sizeof(stage3_table_be_noapos_00000) /
1698 							sizeof(*stage3_table_be_noapos_00000);
1699 
1700 		for (j = 0; j < numelems; j++) {
1701 			const entity_stage3_row *r = &entity_table.table[j];
1702 			if (r->data.ent.entity == NULL)
1703 				continue;
1704 
1705 			if (((j == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1706 					(j == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1707 				continue;
1708 
1709 			/* charset is indifferent, used cs_8859_1 for efficiency */
1710 			write_s3row_data(r, j, cs_8859_1, return_value);
1711 		}
1712 	}
1713 }
1714 /* }}} */
1715 
1716 /*
1717  * Local variables:
1718  * tab-width: 4
1719  * c-basic-offset: 4
1720  * End:
1721  * vim600: sw=4 ts=4 fdm=marker
1722  * vim<600: sw=4 ts=4
1723  */
1724