1 /*	$NetBSD: unvis.c,v 1.36 2011/03/18 09:07:20 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include "config.h"
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 #if 0
36 static char sccsid[] = "@(#)unvis.c	8.1 (Berkeley) 6/4/93";
37 #else
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 /* XXXMYSQL : Make compiler happy. */
42 #ifdef _LIBC
43 #include "namespace.h"
44 #endif
45 
46 #include <sys/types.h>
47 
48 #include <assert.h>
49 #include <ctype.h>
50 
51 /* XXXMYSQL : stdint.h might not be available on older Solaris platforms. */
52 #if defined(__sun) || defined(__sun__)
53 #include <sys/inttypes.h>
54 #else
55 #include <stdint.h>
56 #endif
57 
58 #include <stdio.h>
59 #include <errno.h>
60 /*
61   XXXMYSQL : Due to different versions of vis.h available,
62              use the one bundled with libedit.
63 */
64 #include "np/vis.h"
65 
66 #ifdef __weak_alias
67 __weak_alias(strnunvisx,_strnunvisx)
68 #endif
69 
70 #if !HAVE_VIS
71 /*
72  * decode driven by state machine
73  */
74 #define	S_GROUND	0	/* haven't seen escape char */
75 #define	S_START		1	/* start decoding special sequence */
76 #define	S_META		2	/* metachar started (M) */
77 #define	S_META1		3	/* metachar more, regular char (-) */
78 #define	S_CTRL		4	/* control char started (^) */
79 #define	S_OCTAL2	5	/* octal digit 2 */
80 #define	S_OCTAL3	6	/* octal digit 3 */
81 #define	S_HEX1		7	/* http hex digit */
82 #define	S_HEX2		8	/* http hex digit 2 */
83 #define S_MIME1		9	/* mime hex digit 1 */
84 #define S_MIME2		10	/* mime hex digit 2 */
85 #define S_EATCRNL	11	/* mime eating CRNL */
86 #define S_AMP		12	/* seen & */
87 #define S_NUMBER	13	/* collecting number */
88 #define S_STRING	14	/* collecting string */
89 
90 #ifndef isoctal
91 #define	isoctal(c)	(((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
92 #endif
93 #define xtod(c)		(isdigit(c) ? (c - '0') : ((tolower(c) - 'a') + 10))
94 #define XTOD(c)		(isdigit(c) ? (c - '0') : ((c - 'A') + 10))
95 
96 /*
97  * RFC 1866
98  */
99 static const struct nv {
100 	const char *name;
101 	uint8_t value;
102 } nv[] = {
103 	{ "AElig",	198 }, /* capital AE diphthong (ligature)  */
104 	{ "Aacute",	193 }, /* capital A, acute accent  */
105 	{ "Acirc",	194 }, /* capital A, circumflex accent  */
106 	{ "Agrave",	192 }, /* capital A, grave accent  */
107 	{ "Aring",	197 }, /* capital A, ring  */
108 	{ "Atilde",	195 }, /* capital A, tilde  */
109 	{ "Auml",	196 }, /* capital A, dieresis or umlaut mark  */
110 	{ "Ccedil",	199 }, /* capital C, cedilla  */
111 	{ "ETH",	208 }, /* capital Eth, Icelandic  */
112 	{ "Eacute",	201 }, /* capital E, acute accent  */
113 	{ "Ecirc",	202 }, /* capital E, circumflex accent  */
114 	{ "Egrave",	200 }, /* capital E, grave accent  */
115 	{ "Euml",	203 }, /* capital E, dieresis or umlaut mark  */
116 	{ "Iacute",	205 }, /* capital I, acute accent  */
117 	{ "Icirc",	206 }, /* capital I, circumflex accent  */
118 	{ "Igrave",	204 }, /* capital I, grave accent  */
119 	{ "Iuml",	207 }, /* capital I, dieresis or umlaut mark  */
120 	{ "Ntilde",	209 }, /* capital N, tilde  */
121 	{ "Oacute",	211 }, /* capital O, acute accent  */
122 	{ "Ocirc",	212 }, /* capital O, circumflex accent  */
123 	{ "Ograve",	210 }, /* capital O, grave accent  */
124 	{ "Oslash",	216 }, /* capital O, slash  */
125 	{ "Otilde",	213 }, /* capital O, tilde  */
126 	{ "Ouml",	214 }, /* capital O, dieresis or umlaut mark  */
127 	{ "THORN",	222 }, /* capital THORN, Icelandic  */
128 	{ "Uacute",	218 }, /* capital U, acute accent  */
129 	{ "Ucirc",	219 }, /* capital U, circumflex accent  */
130 	{ "Ugrave",	217 }, /* capital U, grave accent  */
131 	{ "Uuml",	220 }, /* capital U, dieresis or umlaut mark  */
132 	{ "Yacute",	221 }, /* capital Y, acute accent  */
133 	{ "aacute",	225 }, /* small a, acute accent  */
134 	{ "acirc",	226 }, /* small a, circumflex accent  */
135 	{ "acute",	180 }, /* acute accent  */
136 	{ "aelig",	230 }, /* small ae diphthong (ligature)  */
137 	{ "agrave",	224 }, /* small a, grave accent  */
138 	{ "amp",	 38 }, /* ampersand  */
139 	{ "aring",	229 }, /* small a, ring  */
140 	{ "atilde",	227 }, /* small a, tilde  */
141 	{ "auml",	228 }, /* small a, dieresis or umlaut mark  */
142 	{ "brvbar",	166 }, /* broken (vertical) bar  */
143 	{ "ccedil",	231 }, /* small c, cedilla  */
144 	{ "cedil",	184 }, /* cedilla  */
145 	{ "cent",	162 }, /* cent sign  */
146 	{ "copy",	169 }, /* copyright sign  */
147 	{ "curren",	164 }, /* general currency sign  */
148 	{ "deg",	176 }, /* degree sign  */
149 	{ "divide",	247 }, /* divide sign  */
150 	{ "eacute",	233 }, /* small e, acute accent  */
151 	{ "ecirc",	234 }, /* small e, circumflex accent  */
152 	{ "egrave",	232 }, /* small e, grave accent  */
153 	{ "eth",	240 }, /* small eth, Icelandic  */
154 	{ "euml",	235 }, /* small e, dieresis or umlaut mark  */
155 	{ "frac12",	189 }, /* fraction one-half  */
156 	{ "frac14",	188 }, /* fraction one-quarter  */
157 	{ "frac34",	190 }, /* fraction three-quarters  */
158 	{ "gt",		 62 }, /* greater than  */
159 	{ "iacute",	237 }, /* small i, acute accent  */
160 	{ "icirc",	238 }, /* small i, circumflex accent  */
161 	{ "iexcl",	161 }, /* inverted exclamation mark  */
162 	{ "igrave",	236 }, /* small i, grave accent  */
163 	{ "iquest",	191 }, /* inverted question mark  */
164 	{ "iuml",	239 }, /* small i, dieresis or umlaut mark  */
165 	{ "laquo",	171 }, /* angle quotation mark, left  */
166 	{ "lt",		 60 }, /* less than  */
167 	{ "macr",	175 }, /* macron  */
168 	{ "micro",	181 }, /* micro sign  */
169 	{ "middot",	183 }, /* middle dot  */
170 	{ "nbsp",	160 }, /* no-break space  */
171 	{ "not",	172 }, /* not sign  */
172 	{ "ntilde",	241 }, /* small n, tilde  */
173 	{ "oacute",	243 }, /* small o, acute accent  */
174 	{ "ocirc",	244 }, /* small o, circumflex accent  */
175 	{ "ograve",	242 }, /* small o, grave accent  */
176 	{ "ordf",	170 }, /* ordinal indicator, feminine  */
177 	{ "ordm",	186 }, /* ordinal indicator, masculine  */
178 	{ "oslash",	248 }, /* small o, slash  */
179 	{ "otilde",	245 }, /* small o, tilde  */
180 	{ "ouml",	246 }, /* small o, dieresis or umlaut mark  */
181 	{ "para",	182 }, /* pilcrow (paragraph sign)  */
182 	{ "plusmn",	177 }, /* plus-or-minus sign  */
183 	{ "pound",	163 }, /* pound sterling sign  */
184 	{ "quot",	 34 }, /* double quote  */
185 	{ "raquo",	187 }, /* angle quotation mark, right  */
186 	{ "reg",	174 }, /* registered sign  */
187 	{ "sect",	167 }, /* section sign  */
188 	{ "shy",	173 }, /* soft hyphen  */
189 	{ "sup1",	185 }, /* superscript one  */
190 	{ "sup2",	178 }, /* superscript two  */
191 	{ "sup3",	179 }, /* superscript three  */
192 	{ "szlig",	223 }, /* small sharp s, German (sz ligature)  */
193 	{ "thorn",	254 }, /* small thorn, Icelandic  */
194 	{ "times",	215 }, /* multiply sign  */
195 	{ "uacute",	250 }, /* small u, acute accent  */
196 	{ "ucirc",	251 }, /* small u, circumflex accent  */
197 	{ "ugrave",	249 }, /* small u, grave accent  */
198 	{ "uml",	168 }, /* umlaut (dieresis)  */
199 	{ "uuml",	252 }, /* small u, dieresis or umlaut mark  */
200 	{ "yacute",	253 }, /* small y, acute accent  */
201 	{ "yen",	165 }, /* yen sign  */
202 	{ "yuml",	255 }, /* small y, dieresis or umlaut mark  */
203 };
204 
205 /*
206  * unvis - decode characters previously encoded by vis
207  */
208 int
unvis(char * cp,int c,int * astate,int flag)209 unvis(char *cp, int c, int *astate, int flag)
210 {
211 	unsigned char uc = (unsigned char)c;
212 	unsigned char st, ia, is, lc;
213 
214 /*
215  * Bottom 8 bits of astate hold the state machine state.
216  * Top 8 bits hold the current character in the http 1866 nv string decoding
217  */
218 #define GS(a)		((a) & 0xff)
219 #define SS(a, b)	(((uint32_t)(a) << 24) | (b))
220 #define GI(a)		((uint32_t)(a) >> 24)
221 
222 	_DIAGASSERT(cp != NULL);
223 	_DIAGASSERT(astate != NULL);
224 	st = GS(*astate);
225 
226 	if (flag & UNVIS_END) {
227 		switch (st) {
228 		case S_OCTAL2:
229 		case S_OCTAL3:
230 		case S_HEX2:
231 			*astate = SS(0, S_GROUND);
232 			return UNVIS_VALID;
233 		case S_GROUND:
234 			return UNVIS_NOCHAR;
235 		default:
236 			return UNVIS_SYNBAD;
237 		}
238 	}
239 
240 	switch (st) {
241 
242 	case S_GROUND:
243 		*cp = 0;
244 		if ((flag & VIS_NOESCAPE) == 0 && c == '\\') {
245 			*astate = SS(0, S_START);
246 			return UNVIS_NOCHAR;
247 		}
248 		if ((flag & VIS_HTTP1808) && c == '%') {
249 			*astate = SS(0, S_HEX1);
250 			return UNVIS_NOCHAR;
251 		}
252 		if ((flag & VIS_HTTP1866) && c == '&') {
253 			*astate = SS(0, S_AMP);
254 			return UNVIS_NOCHAR;
255 		}
256 		if ((flag & VIS_MIMESTYLE) && c == '=') {
257 			*astate = SS(0, S_MIME1);
258 			return UNVIS_NOCHAR;
259 		}
260 		*cp = c;
261 		return UNVIS_VALID;
262 
263 	case S_START:
264 		switch(c) {
265 		case '\\':
266 			*cp = c;
267 			*astate = SS(0, S_GROUND);
268 			return UNVIS_VALID;
269 		case '0': case '1': case '2': case '3':
270 		case '4': case '5': case '6': case '7':
271 			*cp = (c - '0');
272 			*astate = SS(0, S_OCTAL2);
273 			return UNVIS_NOCHAR;
274 		case 'M':
275 			*cp = (char)0200;
276 			*astate = SS(0, S_META);
277 			return UNVIS_NOCHAR;
278 		case '^':
279 			*astate = SS(0, S_CTRL);
280 			return UNVIS_NOCHAR;
281 		case 'n':
282 			*cp = '\n';
283 			*astate = SS(0, S_GROUND);
284 			return UNVIS_VALID;
285 		case 'r':
286 			*cp = '\r';
287 			*astate = SS(0, S_GROUND);
288 			return UNVIS_VALID;
289 		case 'b':
290 			*cp = '\b';
291 			*astate = SS(0, S_GROUND);
292 			return UNVIS_VALID;
293 		case 'a':
294 			*cp = '\007';
295 			*astate = SS(0, S_GROUND);
296 			return UNVIS_VALID;
297 		case 'v':
298 			*cp = '\v';
299 			*astate = SS(0, S_GROUND);
300 			return UNVIS_VALID;
301 		case 't':
302 			*cp = '\t';
303 			*astate = SS(0, S_GROUND);
304 			return UNVIS_VALID;
305 		case 'f':
306 			*cp = '\f';
307 			*astate = SS(0, S_GROUND);
308 			return UNVIS_VALID;
309 		case 's':
310 			*cp = ' ';
311 			*astate = SS(0, S_GROUND);
312 			return UNVIS_VALID;
313 		case 'E':
314 			*cp = '\033';
315 			*astate = SS(0, S_GROUND);
316 			return UNVIS_VALID;
317 		case '\n':
318 			/*
319 			 * hidden newline
320 			 */
321 			*astate = SS(0, S_GROUND);
322 			return UNVIS_NOCHAR;
323 		case '$':
324 			/*
325 			 * hidden marker
326 			 */
327 			*astate = SS(0, S_GROUND);
328 			return UNVIS_NOCHAR;
329 		}
330 		goto bad;
331 
332 	case S_META:
333 		if (c == '-')
334 			*astate = SS(0, S_META1);
335 		else if (c == '^')
336 			*astate = SS(0, S_CTRL);
337 		else
338 			goto bad;
339 		return UNVIS_NOCHAR;
340 
341 	case S_META1:
342 		*astate = SS(0, S_GROUND);
343 		*cp |= c;
344 		return UNVIS_VALID;
345 
346 	case S_CTRL:
347 		if (c == '?')
348 			*cp |= 0177;
349 		else
350 			*cp |= c & 037;
351 		*astate = SS(0, S_GROUND);
352 		return UNVIS_VALID;
353 
354 	case S_OCTAL2:	/* second possible octal digit */
355 		if (isoctal(uc)) {
356 			/*
357 			 * yes - and maybe a third
358 			 */
359 			*cp = (*cp << 3) + (c - '0');
360 			*astate = SS(0, S_OCTAL3);
361 			return UNVIS_NOCHAR;
362 		}
363 		/*
364 		 * no - done with current sequence, push back passed char
365 		 */
366 		*astate = SS(0, S_GROUND);
367 		return UNVIS_VALIDPUSH;
368 
369 	case S_OCTAL3:	/* third possible octal digit */
370 		*astate = SS(0, S_GROUND);
371 		if (isoctal(uc)) {
372 			*cp = (*cp << 3) + (c - '0');
373 			return UNVIS_VALID;
374 		}
375 		/*
376 		 * we were done, push back passed char
377 		 */
378 		return UNVIS_VALIDPUSH;
379 
380 	case S_HEX1:
381 		if (isxdigit(uc)) {
382 			*cp = xtod(uc);
383 			*astate = SS(0, S_HEX2);
384 			return UNVIS_NOCHAR;
385 		}
386 		/*
387 		 * no - done with current sequence, push back passed char
388 		 */
389 		*astate = SS(0, S_GROUND);
390 		return UNVIS_VALIDPUSH;
391 
392 	case S_HEX2:
393 		*astate = S_GROUND;
394 		if (isxdigit(uc)) {
395 			*cp = xtod(uc) | (*cp << 4);
396 			return UNVIS_VALID;
397 		}
398 		return UNVIS_VALIDPUSH;
399 
400 	case S_MIME1:
401 		if (uc == '\n' || uc == '\r') {
402 			*astate = SS(0, S_EATCRNL);
403 			return UNVIS_NOCHAR;
404 		}
405 		if (isxdigit(uc) && (isdigit(uc) || isupper(uc))) {
406 			*cp = XTOD(uc);
407 			*astate = SS(0, S_MIME2);
408 			return UNVIS_NOCHAR;
409 		}
410 		goto bad;
411 
412 	case S_MIME2:
413 		if (isxdigit(uc) && (isdigit(uc) || isupper(uc))) {
414 			*astate = SS(0, S_GROUND);
415 			*cp = XTOD(uc) | (*cp << 4);
416 			return UNVIS_VALID;
417 		}
418 		goto bad;
419 
420 	case S_EATCRNL:
421 		switch (uc) {
422 		case '\r':
423 		case '\n':
424 			return UNVIS_NOCHAR;
425 		case '=':
426 			*astate = SS(0, S_MIME1);
427 			return UNVIS_NOCHAR;
428 		default:
429 			*cp = uc;
430 			*astate = SS(0, S_GROUND);
431 			return UNVIS_VALID;
432 		}
433 
434 	case S_AMP:
435 		*cp = 0;
436 		if (uc == '#') {
437 			*astate = SS(0, S_NUMBER);
438 			return UNVIS_NOCHAR;
439 		}
440 		*astate = SS(0, S_STRING);
441 		/*FALLTHROUGH*/
442 
443 	case S_STRING:
444 		ia = *cp;		/* index in the array */
445 		is = GI(*astate);	/* index in the string */
446 		lc = is == 0 ? 0 : nv[ia].name[is - 1];	/* last character */
447 
448 		if (uc == ';')
449 			uc = '\0';
450 
451 		for (; ia < __arraycount(nv); ia++) {
452 			if (is != 0 && nv[ia].name[is - 1] != lc)
453 				goto bad;
454 			if (nv[ia].name[is] == uc)
455 				break;
456 		}
457 
458 		if (ia == __arraycount(nv))
459 			goto bad;
460 
461 		if (uc != 0) {
462 			*cp = ia;
463 			*astate = SS(is + 1, S_STRING);
464 			return UNVIS_NOCHAR;
465 		}
466 
467 		*cp = nv[ia].value;
468 		*astate = SS(0, S_GROUND);
469 		return UNVIS_VALID;
470 
471 	case S_NUMBER:
472 		if (uc == ';')
473 			return UNVIS_VALID;
474 		if (!isdigit(uc))
475 			goto bad;
476 		*cp += (*cp * 10) + uc - '0';
477 		return UNVIS_NOCHAR;
478 
479 	default:
480 	bad:
481 		/*
482 		 * decoder in unknown state - (probably uninitialized)
483 		 */
484 		*astate = SS(0, S_GROUND);
485 		return UNVIS_SYNBAD;
486 	}
487 }
488 
489 /*
490  * strnunvisx - decode src into dst
491  *
492  *	Number of chars decoded into dst is returned, -1 on error.
493  *	Dst is null terminated.
494  */
495 
496 int
strnunvisx(char * dst,size_t dlen,const char * src,int flag)497 strnunvisx(char *dst, size_t dlen, const char *src, int flag)
498 {
499 	char c;
500 	char t, *start = dst;
501 	int state = 0;
502 
503 	_DIAGASSERT(src != NULL);
504 	_DIAGASSERT(dst != NULL);
505 #define CHECKSPACE() \
506 	do { \
507 		if (dlen-- == 0) { \
508 			errno = ENOSPC; \
509 			return -1; \
510 		} \
511 	} while (/*CONSTCOND*/0)
512 
513 	while ((c = *src++) != '\0') {
514  again:
515 		switch (unvis(&t, c, &state, flag)) {
516 		case UNVIS_VALID:
517 			CHECKSPACE();
518 			*dst++ = t;
519 			break;
520 		case UNVIS_VALIDPUSH:
521 			CHECKSPACE();
522 			*dst++ = t;
523 			goto again;
524 		case 0:
525 		case UNVIS_NOCHAR:
526 			break;
527 		case UNVIS_SYNBAD:
528 			errno = EINVAL;
529 			return -1;
530 		default:
531 			_DIAGASSERT(0);
532 			errno = EINVAL;
533 			return -1;
534 		}
535 	}
536 	if (unvis(&t, c, &state, UNVIS_END) == UNVIS_VALID) {
537 		CHECKSPACE();
538 		*dst++ = t;
539 	}
540 	CHECKSPACE();
541 	*dst = '\0';
542 	return (int)(dst - start);
543 }
544 
545 int
strunvisx(char * dst,const char * src,int flag)546 strunvisx(char *dst, const char *src, int flag)
547 {
548 	return strnunvisx(dst, (size_t)~0, src, flag);
549 }
550 
551 int
strunvis(char * dst,const char * src)552 strunvis(char *dst, const char *src)
553 {
554 	return strnunvisx(dst, (size_t)~0, src, 0);
555 }
556 
557 int
strnunvis(char * dst,size_t dlen,const char * src)558 strnunvis(char *dst, size_t dlen, const char *src)
559 {
560 	return strnunvisx(dst, dlen, src, 0);
561 }
562 #endif
563