1/*	$NetBSD: vis.c,v 1.2 2017/01/28 21:31:50 christos Exp $	*/
2
3/*	NetBSD: vis.c,v 1.37 2008/07/25 22:29:23 dsl Exp	*/
4
5/*-
6 * Copyright (c) 1989, 1993
7 *	The Regents of the University of California.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/*-
35 * Copyright (c) 1999, 2005 The NetBSD Foundation, Inc.
36 * All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 *    notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 *    notice, this list of conditions and the following disclaimer in the
45 *    documentation and/or other materials provided with the distribution.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
48 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
49 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
50 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
51 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
57 * POSSIBILITY OF SUCH DAMAGE.
58 */
59
60#if 1
61#include <config.h>
62#include <krb5/roken.h>
63#ifndef _DIAGASSERT
64#define _DIAGASSERT(X)
65#endif
66#else /* heimdal */
67#include <sys/cdefs.h>
68#if defined(LIBC_SCCS) && !defined(lint)
69__RCSID("NetBSD: vis.c,v 1.37 2008/07/25 22:29:23 dsl Exp");
70#endif /* LIBC_SCCS and not lint */
71
72#include "namespace.h"
73#endif /* heimdal */
74
75#include <sys/types.h>
76
77#include <assert.h>
78#include <ctype.h>
79#include <limits.h>
80#include <stdio.h>
81#include <string.h>
82#include <vis.h>
83#include <stdlib.h>
84
85#if 0
86#ifdef __weak_alias
87__weak_alias(strsvis,_strsvis)
88__weak_alias(strsvisx,_strsvisx)
89__weak_alias(strvis,_strvis)
90__weak_alias(strvisx,_strvisx)
91__weak_alias(svis,_svis)
92__weak_alias(vis,_vis)
93#endif
94#endif
95
96#if !HAVE_VIS || !HAVE_SVIS
97#include <ctype.h>
98#include <limits.h>
99#include <stdio.h>
100#include <string.h>
101
102static char *do_svis(char *, int, int, int, const char *);
103
104#undef BELL
105#if defined(__STDC__)
106#define BELL '\a'
107#else
108#define BELL '\007'
109#endif
110
111ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
112	rk_vis (char *, int, int, int);
113ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
114	rk_svis (char *, int, int, int, const char *);
115ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
116	rk_strvis (char *, const char *, int);
117ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
118	rk_strsvis (char *, const char *, int, const char *);
119ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
120	rk_strvisx (char *, const char *, size_t, int);
121ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
122	rk_strsvisx (char *, const char *, size_t, int, const char *);
123
124
125#define isoctal(c)	(((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
126#define iswhite(c)	(c == ' ' || c == '\t' || c == '\n')
127#define issafe(c)	(c == '\b' || c == BELL || c == '\r')
128#define xtoa(c)		"0123456789abcdef"[c]
129
130#define MAXEXTRAS	5
131
132#define MAKEEXTRALIST(flag, extra, orig_str)				      \
133do {									      \
134	const char *orig = orig_str;					      \
135	const char *o = orig;						      \
136	char *e;							      \
137	while (*o++)							      \
138		continue;						      \
139	extra = malloc((size_t)((o - orig) + MAXEXTRAS));		      \
140	if (!extra) break;						      \
141	for (o = orig, e = extra; (*e++ = *o++) != '\0';)		      \
142		continue;						      \
143	e--;								      \
144	if (flag & VIS_SP) *e++ = ' ';					      \
145	if (flag & VIS_TAB) *e++ = '\t';				      \
146	if (flag & VIS_NL) *e++ = '\n';					      \
147	if ((flag & VIS_NOSLASH) == 0) *e++ = '\\';			      \
148	*e = '\0';							      \
149} while (/*CONSTCOND*/0)
150
151/*
152 * This is do_hvis, for HTTP style (RFC 1808)
153 */
154static char *
155do_hvis(char *dst, int c, int flag, int nextc, const char *extra)
156{
157	if (!isascii(c) || !isalnum(c) || strchr("$-_.+!*'(),", c) != NULL) {
158		*dst++ = '%';
159		*dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
160		*dst++ = xtoa((unsigned int)c & 0xf);
161	} else {
162		dst = do_svis(dst, c, flag, nextc, extra);
163	}
164	return dst;
165}
166
167/*
168 * This is do_vis, the central code of vis.
169 * dst:	      Pointer to the destination buffer
170 * c:	      Character to encode
171 * flag:      Flag word
172 * nextc:     The character following 'c'
173 * extra:     Pointer to the list of extra characters to be
174 *	      backslash-protected.
175 */
176static char *
177do_svis(char *dst, int c, int flag, int nextc, const char *extra)
178{
179	int isextra;
180	isextra = strchr(extra, c) != NULL;
181	if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) ||
182	    ((flag & VIS_SAFE) && issafe(c)))) {
183		*dst++ = c;
184		return dst;
185	}
186	if (flag & VIS_CSTYLE) {
187		switch (c) {
188		case '\n':
189			*dst++ = '\\'; *dst++ = 'n';
190			return dst;
191		case '\r':
192			*dst++ = '\\'; *dst++ = 'r';
193			return dst;
194		case '\b':
195			*dst++ = '\\'; *dst++ = 'b';
196			return dst;
197		case BELL:
198			*dst++ = '\\'; *dst++ = 'a';
199			return dst;
200		case '\v':
201			*dst++ = '\\'; *dst++ = 'v';
202			return dst;
203		case '\t':
204			*dst++ = '\\'; *dst++ = 't';
205			return dst;
206		case '\f':
207			*dst++ = '\\'; *dst++ = 'f';
208			return dst;
209		case ' ':
210			*dst++ = '\\'; *dst++ = 's';
211			return dst;
212		case '\0':
213			*dst++ = '\\'; *dst++ = '0';
214			if (isoctal(nextc)) {
215				*dst++ = '0';
216				*dst++ = '0';
217			}
218			return dst;
219		default:
220			if (isgraph(c)) {
221				*dst++ = '\\'; *dst++ = c;
222				return dst;
223			}
224		}
225	}
226	if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) {
227		*dst++ = '\\';
228		*dst++ = (u_char)(((unsigned int)(u_char)c >> 6) & 03) + '0';
229		*dst++ = (u_char)(((unsigned int)(u_char)c >> 3) & 07) + '0';
230		*dst++ = (u_char)(			 c       & 07) + '0';
231	} else {
232		if ((flag & VIS_NOSLASH) == 0) *dst++ = '\\';
233		if (c & 0200) {
234			c &= 0177; *dst++ = 'M';
235		}
236		if (iscntrl(c)) {
237			*dst++ = '^';
238			if (c == 0177)
239				*dst++ = '?';
240			else
241				*dst++ = c + '@';
242		} else {
243			*dst++ = '-'; *dst++ = c;
244		}
245	}
246	return dst;
247}
248
249
250/*
251 * svis - visually encode characters, also encoding the characters
252 *	  pointed to by `extra'
253 */
254ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
255rk_svis(char *dst, int c, int flag, int nextc, const char *extra)
256{
257	char *nextra = NULL;
258
259	_DIAGASSERT(dst != NULL);
260	_DIAGASSERT(extra != NULL);
261	MAKEEXTRALIST(flag, nextra, extra);
262	if (!nextra) {
263		*dst = '\0';		/* can't create nextra, return "" */
264		return dst;
265	}
266	if (flag & VIS_HTTPSTYLE)
267		dst = do_hvis(dst, c, flag, nextc, nextra);
268	else
269		dst = do_svis(dst, c, flag, nextc, nextra);
270	free(nextra);
271	*dst = '\0';
272	return dst;
273}
274
275
276/*
277 * strsvis, strsvisx - visually encode characters from src into dst
278 *
279 *	Extra is a pointer to a \0-terminated list of characters to
280 *	be encoded, too. These functions are useful e. g. to
281 *	encode strings in such a way so that they are not interpreted
282 *	by a shell.
283 *
284 *	Dst must be 4 times the size of src to account for possible
285 *	expansion.  The length of dst, not including the trailing NULL,
286 *	is returned.
287 *
288 *	Strsvisx encodes exactly len bytes from src into dst.
289 *	This is useful for encoding a block of data.
290 */
291
292ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
293rk_strsvis(char *dst, const char *csrc, int flag, const char *extra)
294{
295	int c;
296	char *start;
297	char *nextra = NULL;
298	const unsigned char *src = (const unsigned char *)csrc;
299
300	_DIAGASSERT(dst != NULL);
301	_DIAGASSERT(src != NULL);
302	_DIAGASSERT(extra != NULL);
303	MAKEEXTRALIST(flag, nextra, extra);
304	if (!nextra) {
305		*dst = '\0';		/* can't create nextra, return "" */
306		return 0;
307	}
308	if (flag & VIS_HTTPSTYLE) {
309		for (start = dst; (c = *src++) != '\0'; /* empty */)
310			dst = do_hvis(dst, c, flag, *src, nextra);
311	} else {
312		for (start = dst; (c = *src++) != '\0'; /* empty */)
313			dst = do_svis(dst, c, flag, *src, nextra);
314	}
315	free(nextra);
316	*dst = '\0';
317	return (dst - start);
318}
319
320
321ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
322rk_strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra)
323{
324	unsigned char c;
325	char *start;
326	char *nextra = NULL;
327	const unsigned char *src = (const unsigned char *)csrc;
328
329	_DIAGASSERT(dst != NULL);
330	_DIAGASSERT(src != NULL);
331	_DIAGASSERT(extra != NULL);
332	MAKEEXTRALIST(flag, nextra, extra);
333	if (! nextra) {
334		*dst = '\0';		/* can't create nextra, return "" */
335		return 0;
336	}
337
338	if (flag & VIS_HTTPSTYLE) {
339		for (start = dst; len > 0; len--) {
340			c = *src++;
341			dst = do_hvis(dst, c, flag, len ? *src : '\0', nextra);
342		}
343	} else {
344		for (start = dst; len > 0; len--) {
345			c = *src++;
346			dst = do_svis(dst, c, flag, len ? *src : '\0', nextra);
347		}
348	}
349	free(nextra);
350	*dst = '\0';
351	return (dst - start);
352}
353#endif
354
355#if !HAVE_VIS
356/*
357 * vis - visually encode characters
358 */
359ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
360rk_vis(char *dst, int c, int flag, int nextc)
361{
362	char *extra = NULL;
363	unsigned char uc = (unsigned char)c;
364
365	_DIAGASSERT(dst != NULL);
366
367	MAKEEXTRALIST(flag, extra, "");
368	if (! extra) {
369		*dst = '\0';		/* can't create extra, return "" */
370		return dst;
371	}
372	if (flag & VIS_HTTPSTYLE)
373		dst = do_hvis(dst, uc, flag, nextc, extra);
374	else
375		dst = do_svis(dst, uc, flag, nextc, extra);
376	free(extra);
377	*dst = '\0';
378	return dst;
379}
380
381
382/*
383 * strvis, strvisx - visually encode characters from src into dst
384 *
385 *	Dst must be 4 times the size of src to account for possible
386 *	expansion.  The length of dst, not including the trailing NULL,
387 *	is returned.
388 *
389 *	Strvisx encodes exactly len bytes from src into dst.
390 *	This is useful for encoding a block of data.
391 */
392ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
393rk_strvis(char *dst, const char *src, int flag)
394{
395	char *extra = NULL;
396	int rv;
397
398	MAKEEXTRALIST(flag, extra, "");
399	if (!extra) {
400		*dst = '\0';		/* can't create extra, return "" */
401		return 0;
402	}
403	rv = strsvis(dst, src, flag, extra);
404	free(extra);
405	return rv;
406}
407
408
409ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
410rk_strvisx(char *dst, const char *src, size_t len, int flag)
411{
412	char *extra = NULL;
413	int rv;
414
415	MAKEEXTRALIST(flag, extra, "");
416	if (!extra) {
417		*dst = '\0';		/* can't create extra, return "" */
418		return 0;
419	}
420	rv = strsvisx(dst, src, len, flag, extra);
421	free(extra);
422	return rv;
423}
424#endif
425