1/*
2   +----------------------------------------------------------------------+
3   | PHP Version 7                                                        |
4   +----------------------------------------------------------------------+
5   | Copyright (c) 1997-2015 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#if 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 */
89static 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 */
101static 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 */
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 */
376static enum entity_charset determine_charset(char *charset_hint)
377{
378    int 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
448det_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 */
472static 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. */
505static 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. */
523static 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 */
549static 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 */
576static 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
651table_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/* {{{ */
698static 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 */
706static 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 */
757static 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 */
792static 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 */
828static 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 */
857static 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
877static 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)
937static 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 = ret->val; 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
1036invalid_code:
1037        for (; p < next; p++) {
1038            *(q++) = *p;
1039        }
1040    }
1041
1042    *q = '\0';
1043    ret->len = (size_t)(q - ret->val);
1044}
1045/* }}} */
1046
1047/* {{{ unescape_inverse_map */
1048static 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 */
1076static 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 */
1098PHPAPI zend_string *php_unescape_html_entities(unsigned char *old, size_t oldlen, int all, int flags, char *hint_charset)
1099{
1100    size_t retlen;
1101    zend_string *ret;
1102    enum entity_charset charset;
1103    const entity_ht *inverse_map = NULL;
1104    size_t new_size = TRAVERSE_FOR_ENTITIES_EXPAND_SIZE(oldlen);
1105
1106    if (all) {
1107        charset = determine_charset(hint_charset);
1108    } else {
1109        charset = cs_8859_1; /* charset shouldn't matter, use ISO-8859-1 for performance */
1110    }
1111
1112    /* don't use LIMIT_ALL! */
1113
1114    if (oldlen > new_size) {
1115        /* overflow, refuse to do anything */
1116        ret = zend_string_init((char*)old, oldlen, 0);
1117        retlen = oldlen;
1118        goto empty_source;
1119    }
1120    ret = zend_string_alloc(new_size, 0);
1121    ret->val[0] = '\0';
1122    ret->len = oldlen;
1123    retlen = oldlen;
1124    if (retlen == 0) {
1125        goto empty_source;
1126    }
1127
1128    inverse_map = unescape_inverse_map(all, flags);
1129
1130    /* replace numeric entities */
1131    traverse_for_entities((char*)old, oldlen, ret, all, flags, inverse_map, charset);
1132
1133empty_source:
1134    return ret;
1135}
1136/* }}} */
1137
1138PHPAPI zend_string *php_escape_html_entities(unsigned char *old, size_t oldlen, int all, int flags, char *hint_charset)
1139{
1140    return php_escape_html_entities_ex(old, oldlen, all, flags, hint_charset, 1);
1141}
1142
1143/* {{{ find_entity_for_char */
1144static inline void find_entity_for_char(
1145    unsigned int k,
1146    enum entity_charset charset,
1147    const entity_stage1_row *table,
1148    const unsigned char **entity,
1149    size_t *entity_len,
1150    unsigned char *old,
1151    size_t oldlen,
1152    size_t *cursor)
1153{
1154    unsigned stage1_idx = ENT_STAGE1_INDEX(k);
1155    const entity_stage3_row *c;
1156
1157    if (stage1_idx > 0x1D) {
1158        *entity     = NULL;
1159        *entity_len = 0;
1160        return;
1161    }
1162
1163    c = &table[stage1_idx][ENT_STAGE2_INDEX(k)][ENT_STAGE3_INDEX(k)];
1164
1165    if (!c->ambiguous) {
1166        *entity     = (const unsigned char *)c->data.ent.entity;
1167        *entity_len = c->data.ent.entity_len;
1168    } else {
1169        /* peek at next char */
1170        size_t   cursor_before  = *cursor;
1171        int      status         = SUCCESS;
1172        unsigned next_char;
1173
1174        if (!(*cursor < oldlen))
1175            goto no_suitable_2nd;
1176
1177        next_char = get_next_char(charset, old, oldlen, cursor, &status);
1178
1179        if (status == FAILURE)
1180            goto no_suitable_2nd;
1181
1182        {
1183            const entity_multicodepoint_row *s, *e;
1184
1185            s = &c->data.multicodepoint_table[1];
1186            e = s - 1 + c->data.multicodepoint_table[0].leading_entry.size;
1187            /* we could do a binary search but it's not worth it since we have
1188             * at most two entries... */
1189            for ( ; s <= e; s++) {
1190                if (s->normal_entry.second_cp == next_char) {
1191                    *entity     = (const unsigned char *) s->normal_entry.entity;
1192                    *entity_len = s->normal_entry.entity_len;
1193                    return;
1194                }
1195            }
1196        }
1197no_suitable_2nd:
1198        *cursor = cursor_before;
1199        *entity = (const unsigned char *)
1200            c->data.multicodepoint_table[0].leading_entry.default_entity;
1201        *entity_len = c->data.multicodepoint_table[0].leading_entry.default_entity_len;
1202    }
1203}
1204/* }}} */
1205
1206/* {{{ find_entity_for_char_basic */
1207static inline void find_entity_for_char_basic(
1208    unsigned int k,
1209    const entity_stage3_row *table,
1210    const unsigned char **entity,
1211    size_t *entity_len)
1212{
1213    if (k >= 64U) {
1214        *entity     = NULL;
1215        *entity_len = 0;
1216        return;
1217    }
1218
1219    *entity     = (const unsigned char *) table[k].data.ent.entity;
1220    *entity_len = table[k].data.ent.entity_len;
1221}
1222/* }}} */
1223
1224/* {{{ php_escape_html_entities
1225 */
1226PHPAPI zend_string *php_escape_html_entities_ex(unsigned char *old, size_t oldlen, int all, int flags, char *hint_charset, zend_bool double_encode)
1227{
1228    size_t cursor, maxlen, len;
1229    zend_string *replaced;
1230    enum entity_charset charset = determine_charset(hint_charset);
1231    int doctype = flags & ENT_HTML_DOC_TYPE_MASK;
1232    entity_table_opt entity_table;
1233    const enc_to_uni *to_uni_table = NULL;
1234    const entity_ht *inv_map = NULL; /* used for !double_encode */
1235    /* only used if flags includes ENT_HTML_IGNORE_ERRORS or ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS */
1236    const unsigned char *replacement = NULL;
1237    size_t replacement_len = 0;
1238
1239    if (all) { /* replace with all named entities */
1240        if (CHARSET_PARTIAL_SUPPORT(charset)) {
1241            php_error_docref0(NULL, E_STRICT, "Only basic entities "
1242                "substitution is supported for multi-byte encodings other than UTF-8; "
1243                "functionality is equivalent to htmlspecialchars");
1244        }
1245        LIMIT_ALL(all, doctype, charset);
1246    }
1247    entity_table = determine_entity_table(all, doctype);
1248    if (all && !CHARSET_UNICODE_COMPAT(charset)) {
1249        to_uni_table = enc_to_uni_index[charset];
1250    }
1251
1252    if (!double_encode) {
1253        /* first arg is 1 because we want to identify valid named entities
1254         * even if we are only encoding the basic ones */
1255        inv_map = unescape_inverse_map(1, flags);
1256    }
1257
1258    if (flags & (ENT_HTML_SUBSTITUTE_ERRORS | ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS)) {
1259        if (charset == cs_utf_8) {
1260            replacement = (const unsigned char*)"\xEF\xBF\xBD";
1261            replacement_len = sizeof("\xEF\xBF\xBD") - 1;
1262        } else {
1263            replacement = (const unsigned char*)"&#xFFFD;";
1264            replacement_len = sizeof("&#xFFFD;") - 1;
1265        }
1266    }
1267
1268    /* initial estimate */
1269    if (oldlen < 64) {
1270        maxlen = 128;
1271    } else {
1272        maxlen = 2 * oldlen;
1273        if (maxlen < oldlen) {
1274            zend_error_noreturn(E_ERROR, "Input string is too long");
1275            return NULL;
1276        }
1277    }
1278
1279    replaced = zend_string_alloc(maxlen, 0);
1280    len = 0;
1281    cursor = 0;
1282    while (cursor < oldlen) {
1283        const unsigned char *mbsequence = NULL;
1284        size_t mbseqlen                 = 0,
1285               cursor_before            = cursor;
1286        int status                      = SUCCESS;
1287        unsigned int this_char          = get_next_char(charset, old, oldlen, &cursor, &status);
1288
1289        /* guarantee we have at least 40 bytes to write.
1290         * In HTML5, entities may take up to 33 bytes */
1291        if (len > maxlen - 40) { /* maxlen can never be smaller than 128 */
1292            replaced = zend_string_safe_realloc(replaced, maxlen, 1, 128, 0);
1293            maxlen += 128;
1294        }
1295
1296        if (status == FAILURE) {
1297            /* invalid MB sequence */
1298            if (flags & ENT_HTML_IGNORE_ERRORS) {
1299                continue;
1300            } else if (flags & ENT_HTML_SUBSTITUTE_ERRORS) {
1301                memcpy(&replaced->val[len], replacement, replacement_len);
1302                len += replacement_len;
1303                continue;
1304            } else {
1305                zend_string_free(replaced);
1306                return STR_EMPTY_ALLOC();
1307            }
1308        } else { /* SUCCESS */
1309            mbsequence = &old[cursor_before];
1310            mbseqlen = cursor - cursor_before;
1311        }
1312
1313        if (this_char != '&') { /* no entity on this position */
1314            const unsigned char *rep    = NULL;
1315            size_t              rep_len = 0;
1316
1317            if (((this_char == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1318                    (this_char == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1319                goto pass_char_through;
1320
1321            if (all) { /* false that CHARSET_PARTIAL_SUPPORT(charset) */
1322                if (to_uni_table != NULL) {
1323                    /* !CHARSET_UNICODE_COMPAT therefore not UTF-8; since UTF-8
1324                     * is the only multibyte encoding with !CHARSET_PARTIAL_SUPPORT,
1325                     * we're using a single byte encoding */
1326                    map_to_unicode(this_char, to_uni_table, &this_char);
1327                    if (this_char == 0xFFFF) /* no mapping; pass through */
1328                        goto pass_char_through;
1329                }
1330                /* the cursor may advance */
1331                find_entity_for_char(this_char, charset, entity_table.ms_table, &rep,
1332                    &rep_len, old, oldlen, &cursor);
1333            } else {
1334                find_entity_for_char_basic(this_char, entity_table.table, &rep, &rep_len);
1335            }
1336
1337            if (rep != NULL) {
1338                replaced->val[len++] = '&';
1339                memcpy(&replaced->val[len], rep, rep_len);
1340                len += rep_len;
1341                replaced->val[len++] = ';';
1342            } else {
1343                /* we did not find an entity for this char.
1344                 * check for its validity, if its valid pass it unchanged */
1345                if (flags & ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS) {
1346                    if (CHARSET_UNICODE_COMPAT(charset)) {
1347                        if (!unicode_cp_is_allowed(this_char, doctype)) {
1348                            mbsequence = replacement;
1349                            mbseqlen = replacement_len;
1350                        }
1351                    } else if (to_uni_table) {
1352                        if (!all) /* otherwise we already did this */
1353                            map_to_unicode(this_char, to_uni_table, &this_char);
1354                        if (!unicode_cp_is_allowed(this_char, doctype)) {
1355                            mbsequence = replacement;
1356                            mbseqlen = replacement_len;
1357                        }
1358                    } else {
1359                        /* not a unicode code point, unless, coincidentally, it's in
1360                         * the 0x20..0x7D range (except 0x5C in sjis). We know nothing
1361                         * about other code points, because we have no tables. Since
1362                         * Unicode code points in that range are not disallowed in any
1363                         * document type, we could do nothing. However, conversion
1364                         * tables frequently map 0x00-0x1F to the respective C0 code
1365                         * points. Let's play it safe and admit that's the case */
1366                        if (this_char <= 0x7D &&
1367                                !unicode_cp_is_allowed(this_char, doctype)) {
1368                            mbsequence = replacement;
1369                            mbseqlen = replacement_len;
1370                        }
1371                    }
1372                }
1373pass_char_through:
1374                if (mbseqlen > 1) {
1375                    memcpy(replaced->val + len, mbsequence, mbseqlen);
1376                    len += mbseqlen;
1377                } else {
1378                    replaced->val[len++] = mbsequence[0];
1379                }
1380            }
1381        } else { /* this_char == '&' */
1382            if (double_encode) {
1383encode_amp:
1384                memcpy(&replaced->val[len], "&amp;", sizeof("&amp;") - 1);
1385                len += sizeof("&amp;") - 1;
1386            } else { /* no double encode */
1387                /* check if entity is valid */
1388                size_t ent_len; /* not counting & or ; */
1389                /* peek at next char */
1390                if (old[cursor] == '#') { /* numeric entity */
1391                    unsigned code_point;
1392                    int valid;
1393                    char *pos = (char*)&old[cursor+1];
1394                    valid = process_numeric_entity((const char **)&pos, &code_point);
1395                    if (valid == FAILURE)
1396                        goto encode_amp;
1397                    if (flags & ENT_HTML_SUBSTITUTE_DISALLOWED_CHARS) {
1398                        if (!numeric_entity_is_allowed(code_point, doctype))
1399                            goto encode_amp;
1400                    }
1401                    ent_len = pos - (char*)&old[cursor];
1402                } else { /* named entity */
1403                    /* check for vality of named entity */
1404                    const char *start = (const char *) &old[cursor],
1405                               *next = start;
1406                    unsigned   dummy1, dummy2;
1407
1408                    if (process_named_entity_html(&next, &start, &ent_len) == FAILURE)
1409                        goto encode_amp;
1410                    if (resolve_named_entity_html(start, ent_len, inv_map, &dummy1, &dummy2) == FAILURE) {
1411                        if (!(doctype == ENT_HTML_DOC_XHTML && ent_len == 4 && start[0] == 'a'
1412                                    && start[1] == 'p' && start[2] == 'o' && start[3] == 's')) {
1413                            /* uses html4 inv_map, which doesn't include apos;. This is a
1414                             * hack to support it */
1415                            goto encode_amp;
1416                        }
1417                    }
1418                }
1419                /* checks passed; copy entity to result */
1420                /* entity size is unbounded, we may need more memory */
1421                /* at this point maxlen - len >= 40 */
1422                if (maxlen - len < ent_len + 2 /* & and ; */) {
1423                    /* ent_len < oldlen, which is certainly <= SIZE_MAX/2 */
1424                    replaced = zend_string_safe_realloc(replaced, maxlen, 1, ent_len + 128, 0);
1425                    maxlen += ent_len + 128;
1426                }
1427                replaced->val[len++] = '&';
1428                memcpy(&replaced->val[len], &old[cursor], ent_len);
1429                len += ent_len;
1430                replaced->val[len++] = ';';
1431                cursor += ent_len + 1;
1432            }
1433        }
1434    }
1435    replaced->val[len] = '\0';
1436    replaced->len = len;
1437
1438    return replaced;
1439}
1440/* }}} */
1441
1442/* {{{ php_html_entities
1443 */
1444static void php_html_entities(INTERNAL_FUNCTION_PARAMETERS, int all)
1445{
1446    zend_string *str, *hint_charset = NULL;
1447    char *default_charset;
1448    zend_long flags = ENT_COMPAT;
1449    zend_string *replaced;
1450    zend_bool double_encode = 1;
1451
1452#ifndef FAST_ZPP
1453    if (zend_parse_parameters(ZEND_NUM_ARGS(), "S|lS!b", &str, &flags, &hint_charset, &double_encode) == FAILURE) {
1454        return;
1455    }
1456#else
1457    ZEND_PARSE_PARAMETERS_START(1, 4)
1458        Z_PARAM_STR(str)
1459        Z_PARAM_OPTIONAL
1460        Z_PARAM_LONG(flags)
1461        Z_PARAM_STR_EX(hint_charset, 1, 0)
1462        Z_PARAM_BOOL(double_encode);
1463    ZEND_PARSE_PARAMETERS_END();
1464#endif
1465
1466    if (!hint_charset) {
1467        default_charset = get_default_charset();
1468    }
1469    replaced = php_escape_html_entities_ex((unsigned char*)str->val, str->len, all, (int) flags, (hint_charset ? hint_charset->val : default_charset), double_encode);
1470    RETVAL_STR(replaced);
1471}
1472/* }}} */
1473
1474#define HTML_SPECIALCHARS   0
1475#define HTML_ENTITIES       1
1476
1477/* {{{ register_html_constants
1478 */
1479void register_html_constants(INIT_FUNC_ARGS)
1480{
1481    REGISTER_LONG_CONSTANT("HTML_SPECIALCHARS", HTML_SPECIALCHARS, CONST_PERSISTENT|CONST_CS);
1482    REGISTER_LONG_CONSTANT("HTML_ENTITIES", HTML_ENTITIES, CONST_PERSISTENT|CONST_CS);
1483    REGISTER_LONG_CONSTANT("ENT_COMPAT", ENT_COMPAT, CONST_PERSISTENT|CONST_CS);
1484    REGISTER_LONG_CONSTANT("ENT_QUOTES", ENT_QUOTES, CONST_PERSISTENT|CONST_CS);
1485    REGISTER_LONG_CONSTANT("ENT_NOQUOTES", ENT_NOQUOTES, CONST_PERSISTENT|CONST_CS);
1486    REGISTER_LONG_CONSTANT("ENT_IGNORE", ENT_IGNORE, CONST_PERSISTENT|CONST_CS);
1487    REGISTER_LONG_CONSTANT("ENT_SUBSTITUTE", ENT_SUBSTITUTE, CONST_PERSISTENT|CONST_CS);
1488    REGISTER_LONG_CONSTANT("ENT_DISALLOWED", ENT_DISALLOWED, CONST_PERSISTENT|CONST_CS);
1489    REGISTER_LONG_CONSTANT("ENT_HTML401", ENT_HTML401, CONST_PERSISTENT|CONST_CS);
1490    REGISTER_LONG_CONSTANT("ENT_XML1", ENT_XML1, CONST_PERSISTENT|CONST_CS);
1491    REGISTER_LONG_CONSTANT("ENT_XHTML", ENT_XHTML, CONST_PERSISTENT|CONST_CS);
1492    REGISTER_LONG_CONSTANT("ENT_HTML5", ENT_HTML5, CONST_PERSISTENT|CONST_CS);
1493}
1494/* }}} */
1495
1496/* {{{ proto string htmlspecialchars(string string [, int quote_style[, string encoding[, bool double_encode]]])
1497   Convert special characters to HTML entities */
1498PHP_FUNCTION(htmlspecialchars)
1499{
1500    php_html_entities(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
1501}
1502/* }}} */
1503
1504/* {{{ proto string htmlspecialchars_decode(string string [, int quote_style])
1505   Convert special HTML entities back to characters */
1506PHP_FUNCTION(htmlspecialchars_decode)
1507{
1508    char *str;
1509    size_t str_len;
1510    zend_long quote_style = ENT_COMPAT;
1511    zend_string *replaced;
1512
1513    if (zend_parse_parameters(ZEND_NUM_ARGS(), "s|l", &str, &str_len, &quote_style) == FAILURE) {
1514        return;
1515    }
1516
1517    replaced = php_unescape_html_entities((unsigned char*)str, str_len, 0 /*!all*/, (int)quote_style, NULL);
1518    if (replaced) {
1519        RETURN_STR(replaced);
1520    }
1521    RETURN_FALSE;
1522}
1523/* }}} */
1524
1525/* {{{ proto string html_entity_decode(string string [, int quote_style][, string encoding])
1526   Convert all HTML entities to their applicable characters */
1527PHP_FUNCTION(html_entity_decode)
1528{
1529    zend_string *str, *hint_charset = NULL;
1530    char *default_charset;
1531    zend_long quote_style = ENT_COMPAT;
1532    zend_string *replaced;
1533
1534#ifndef FAST_ZPP
1535    if (zend_parse_parameters(ZEND_NUM_ARGS(), "S|lS", &str,
1536                              &quote_style, &hint_charset) == FAILURE) {
1537        return;
1538    }
1539#else
1540    ZEND_PARSE_PARAMETERS_START(1, 3)
1541        Z_PARAM_STR(str)
1542        Z_PARAM_OPTIONAL
1543        Z_PARAM_LONG(quote_style)
1544        Z_PARAM_STR(hint_charset)
1545    ZEND_PARSE_PARAMETERS_END();
1546#endif
1547
1548    if (!hint_charset) {
1549        default_charset = get_default_charset();
1550    }
1551    replaced = php_unescape_html_entities((unsigned char*)str->val, str->len, 1 /*all*/, (int)quote_style, (hint_charset ? hint_charset->val : default_charset));
1552
1553    if (replaced) {
1554        RETURN_STR(replaced);
1555    }
1556    RETURN_FALSE;
1557}
1558/* }}} */
1559
1560
1561/* {{{ proto string htmlentities(string string [, int quote_style[, string encoding[, bool double_encode]]])
1562   Convert all applicable characters to HTML entities */
1563PHP_FUNCTION(htmlentities)
1564{
1565    php_html_entities(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
1566}
1567/* }}} */
1568
1569/* {{{ write_s3row_data */
1570static inline void write_s3row_data(
1571    const entity_stage3_row *r,
1572    unsigned orig_cp,
1573    enum entity_charset charset,
1574    zval *arr)
1575{
1576    char key[9] = ""; /* two unicode code points in UTF-8 */
1577    char entity[LONGEST_ENTITY_LENGTH + 2] = {'&'};
1578    size_t written_k1;
1579
1580    written_k1 = write_octet_sequence((unsigned char*)key, charset, orig_cp);
1581
1582    if (!r->ambiguous) {
1583        size_t l = r->data.ent.entity_len;
1584        memcpy(&entity[1], r->data.ent.entity, l);
1585        entity[l + 1] = ';';
1586        add_assoc_stringl_ex(arr, key, written_k1, entity, l + 2);
1587    } else {
1588        unsigned i,
1589                 num_entries;
1590        const entity_multicodepoint_row *mcpr = r->data.multicodepoint_table;
1591
1592        if (mcpr[0].leading_entry.default_entity != NULL) {
1593            size_t l = mcpr[0].leading_entry.default_entity_len;
1594            memcpy(&entity[1], mcpr[0].leading_entry.default_entity, l);
1595            entity[l + 1] = ';';
1596            add_assoc_stringl_ex(arr, key, written_k1, entity, l + 2);
1597        }
1598        num_entries = mcpr[0].leading_entry.size;
1599        for (i = 1; i <= num_entries; i++) {
1600            size_t   l,
1601                     written_k2;
1602            unsigned uni_cp,
1603                     spe_cp;
1604
1605            uni_cp = mcpr[i].normal_entry.second_cp;
1606            l = mcpr[i].normal_entry.entity_len;
1607
1608            if (!CHARSET_UNICODE_COMPAT(charset)) {
1609                if (map_from_unicode(uni_cp, charset, &spe_cp) == FAILURE)
1610                    continue; /* non representable in this charset */
1611            } else {
1612                spe_cp = uni_cp;
1613            }
1614
1615            written_k2 = write_octet_sequence((unsigned char*)&key[written_k1], charset, spe_cp);
1616            memcpy(&entity[1], mcpr[i].normal_entry.entity, l);
1617            entity[l + 1] = ';';
1618            entity[l + 1] = '\0';
1619            add_assoc_stringl_ex(arr, key, written_k1 + written_k2, entity, l + 1);
1620        }
1621    }
1622}
1623/* }}} */
1624
1625/* {{{ proto array get_html_translation_table([int table [, int flags [, string encoding]]])
1626   Returns the internal translation table used by htmlspecialchars and htmlentities */
1627PHP_FUNCTION(get_html_translation_table)
1628{
1629    zend_long all = HTML_SPECIALCHARS,
1630         flags = ENT_COMPAT;
1631    int doctype;
1632    entity_table_opt entity_table;
1633    const enc_to_uni *to_uni_table = NULL;
1634    char *charset_hint = NULL;
1635    size_t charset_hint_len;
1636    enum entity_charset charset;
1637
1638    /* in this function we have to jump through some loops because we're
1639     * getting the translated table from data structures that are optimized for
1640     * random access, not traversal */
1641
1642    if (zend_parse_parameters(ZEND_NUM_ARGS(), "|lls",
1643            &all, &flags, &charset_hint, &charset_hint_len) == FAILURE) {
1644        return;
1645    }
1646
1647    charset = determine_charset(charset_hint);
1648    doctype = flags & ENT_HTML_DOC_TYPE_MASK;
1649    LIMIT_ALL(all, doctype, charset);
1650
1651    array_init(return_value);
1652
1653    entity_table = determine_entity_table((int)all, doctype);
1654    if (all && !CHARSET_UNICODE_COMPAT(charset)) {
1655        to_uni_table = enc_to_uni_index[charset];
1656    }
1657
1658    if (all) { /* HTML_ENTITIES (actually, any non-zero value for 1st param) */
1659        const entity_stage1_row *ms_table = entity_table.ms_table;
1660
1661        if (CHARSET_UNICODE_COMPAT(charset)) {
1662            unsigned i, j, k,
1663                     max_i, max_j, max_k;
1664            /* no mapping to unicode required */
1665            if (CHARSET_SINGLE_BYTE(charset)) { /* ISO-8859-1 */
1666                max_i = 1; max_j = 4; max_k = 64;
1667            } else {
1668                max_i = 0x1E; max_j = 64; max_k = 64;
1669            }
1670
1671            for (i = 0; i < max_i; i++) {
1672                if (ms_table[i] == empty_stage2_table)
1673                    continue;
1674                for (j = 0; j < max_j; j++) {
1675                    if (ms_table[i][j] == empty_stage3_table)
1676                        continue;
1677                    for (k = 0; k < max_k; k++) {
1678                        const entity_stage3_row *r = &ms_table[i][j][k];
1679                        unsigned code;
1680
1681                        if (r->data.ent.entity == NULL)
1682                            continue;
1683
1684                        code = ENT_CODE_POINT_FROM_STAGES(i, j, k);
1685                        if (((code == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1686                                (code == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1687                            continue;
1688                        write_s3row_data(r, code, charset, return_value);
1689                    }
1690                }
1691            }
1692        } else {
1693            /* we have to iterate through the set of code points for this
1694             * encoding and map them to unicode code points */
1695            unsigned i;
1696            for (i = 0; i <= 0xFF; i++) {
1697                const entity_stage3_row *r;
1698                unsigned uni_cp;
1699
1700                /* can be done before mapping, they're invariant */
1701                if (((i == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1702                        (i == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1703                    continue;
1704
1705                map_to_unicode(i, to_uni_table, &uni_cp);
1706                r = &ms_table[ENT_STAGE1_INDEX(uni_cp)][ENT_STAGE2_INDEX(uni_cp)][ENT_STAGE3_INDEX(uni_cp)];
1707                if (r->data.ent.entity == NULL)
1708                    continue;
1709
1710                write_s3row_data(r, i, charset, return_value);
1711            }
1712        }
1713    } else {
1714        /* we could use sizeof(stage3_table_be_apos_00000) as well */
1715        unsigned      j,
1716                      numelems = sizeof(stage3_table_be_noapos_00000) /
1717                            sizeof(*stage3_table_be_noapos_00000);
1718
1719        for (j = 0; j < numelems; j++) {
1720            const entity_stage3_row *r = &entity_table.table[j];
1721            if (r->data.ent.entity == NULL)
1722                continue;
1723
1724            if (((j == '\'' && !(flags & ENT_HTML_QUOTE_SINGLE)) ||
1725                    (j == '"' && !(flags & ENT_HTML_QUOTE_DOUBLE))))
1726                continue;
1727
1728            /* charset is indifferent, used cs_8859_1 for efficiency */
1729            write_s3row_data(r, j, cs_8859_1, return_value);
1730        }
1731    }
1732}
1733/* }}} */
1734
1735/*
1736 * Local variables:
1737 * tab-width: 4
1738 * c-basic-offset: 4
1739 * End:
1740 * vim600: sw=4 ts=4 fdm=marker
1741 * vim<600: sw=4 ts=4
1742 */
1743