1/*
2 * Copyright (c) 2009-2011 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29/*	$KAME: advcap.c,v 1.11 2003/05/19 09:46:50 keiichi Exp $	*/
30
31/*
32 * Copyright (c) 1983 The Regents of the University of California.
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 *    notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 *    notice, this list of conditions and the following disclaimer in the
42 *    documentation and/or other materials provided with the distribution.
43 * 3. All advertising materials mentioning features or use of this software
44 *    must display the following acknowledgement:
45 *	This product includes software developed by the University of
46 *	California, Berkeley and its contributors.
47 * 4. Neither the name of the University nor the names of its contributors
48 *    may be used to endorse or promote products derived from this software
49 *    without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 */
63
64/*
65 * remcap - routines for dealing with the remote host data base
66 *
67 * derived from termcap
68 */
69#include <sys/types.h>
70#include <sys/uio.h>
71#include <unistd.h>
72#include <fcntl.h>
73#include <ctype.h>
74#include <stdlib.h>
75#include <stdio.h>
76#include <syslog.h>
77#include <errno.h>
78#include <string.h>
79#include "pathnames.h"
80
81#ifndef BUFSIZ
82#define	BUFSIZ		1024
83#endif
84#define MAXHOP		32		/* max number of tc= indirections */
85
86#define	tgetent		agetent
87#define	tnchktc		anchktc
88#define	tnamatch	anamatch
89#define	tgetnum		agetnum
90#define	tgetflag	agetflag
91#define	tgetstr		agetstr
92
93#if 0
94#define V_TERMCAP	"REMOTE"
95#define V_TERM		"HOST"
96#endif
97
98char	*RM;
99
100/*
101 * termcap - routines for dealing with the terminal capability data base
102 *
103 * BUG:		Should use a "last" pointer in tbuf, so that searching
104 *		for capabilities alphabetically would not be a n**2/2
105 *		process when large numbers of capabilities are given.
106 * Note:	If we add a last pointer now we will screw up the
107 *		tc capability. We really should compile termcap.
108 *
109 * Essentially all the work here is scanning and decoding escapes
110 * in string capabilities.  We don't use stdio because the editor
111 * doesn't, and because living w/o it is not hard.
112 */
113
114static	char *tbuf;
115static	int hopcount;	/* detect infinite loops in termcap, init 0 */
116
117static	char *remotefile;
118
119extern char *conffile;
120
121int tgetent(char *, char *);
122int getent(char *, char *, char *);
123int tnchktc(void);
124int tnamatch(char *);
125static char *tskip(char *);
126int64_t tgetnum(char *);
127int tgetflag(char *);
128char *tgetstr(char *, char **);
129static char *tdecode(char *, char **);
130
131/*
132 * Get an entry for terminal name in buffer bp,
133 * from the termcap file.  Parse is very rudimentary;
134 * we just notice escaped newlines.
135 */
136int
137tgetent(bp, name)
138	char *bp, *name;
139{
140	char *cp;
141
142	remotefile = cp = conffile ? conffile : _PATH_RTADVDCONF;
143	return (getent(bp, name, cp));
144}
145
146int
147getent(bp, name, cp)
148	char *bp, *name, *cp;
149{
150	int c;
151	int i = 0, cnt = 0;
152	char ibuf[BUFSIZ];
153	int tf;
154
155	tbuf = bp;
156	tf = 0;
157	/*
158	 * TERMCAP can have one of two things in it. It can be the
159	 * name of a file to use instead of /etc/termcap. In this
160	 * case it better start with a "/". Or it can be an entry to
161	 * use so we don't have to read the file. In this case it
162	 * has to already have the newlines crunched out.
163	 */
164	if (cp && *cp) {
165		tf = open(RM = cp, O_RDONLY);
166	}
167	if (tf < 0) {
168		syslog(LOG_INFO,
169		       "<%s> open: %s", __func__, strerror(errno));
170		return (-2);
171	}
172	for (;;) {
173		cp = bp;
174		for (;;) {
175			if (i == cnt) {
176				cnt = read(tf, ibuf, BUFSIZ);
177				if (cnt <= 0) {
178					close(tf);
179					return (0);
180				}
181				i = 0;
182			}
183			c = ibuf[i++];
184			if (c == '\n') {
185				if (cp > bp && cp[-1] == '\\') {
186					cp--;
187					continue;
188				}
189				break;
190			}
191			if (cp >= bp + BUFSIZ) {
192				write(STDERR_FILENO, "Remcap entry too long\n",
193				      23);
194				break;
195			} else
196				*cp++ = c;
197		}
198		*cp = 0;
199
200		/*
201		 * The real work for the match.
202		 */
203		if (tnamatch(name)) {
204			close(tf);
205			return (tnchktc());
206		}
207	}
208}
209
210/*
211 * tnchktc: check the last entry, see if it's tc=xxx. If so,
212 * recursively find xxx and append that entry (minus the names)
213 * to take the place of the tc=xxx entry. This allows termcap
214 * entries to say "like an HP2621 but doesn't turn on the labels".
215 * Note that this works because of the left to right scan.
216 */
217int
218tnchktc()
219{
220	char *p, *q;
221	char tcname[16];	/* name of similar terminal */
222	char tcbuf[BUFSIZ];
223	char *holdtbuf = tbuf;
224	int l;
225
226	p = tbuf + strlen(tbuf) - 2;	/* before the last colon */
227	while (*--p != ':')
228		if (p < tbuf) {
229			write(STDERR_FILENO, "Bad remcap entry\n", 18);
230			return (0);
231		}
232	p++;
233	/* p now points to beginning of last field */
234	if (p[0] != 't' || p[1] != 'c')
235		return (1);
236	strlcpy(tcname, p + 3, sizeof tcname);
237	q = tcname;
238	while (*q && *q != ':')
239		q++;
240	*q = 0;
241	if (++hopcount > MAXHOP) {
242		write(STDERR_FILENO, "Infinite tc= loop\n", 18);
243		return (0);
244	}
245	if (getent(tcbuf, tcname, remotefile) != 1) {
246		return (0);
247	}
248	for (q = tcbuf; *q++ != ':'; )
249		;
250	l = p - holdtbuf + strlen(q);
251
252	/* check length before copying string below */
253	if (l > BUFSIZ) {
254		write(STDERR_FILENO, "Remcap entry too long\n", 23);
255		q[BUFSIZ - (p-holdtbuf)] = 0;
256	}
257	strlcpy(p, q, p-tbuf);
258	tbuf = holdtbuf;
259	return (1);
260}
261
262/*
263 * Tnamatch deals with name matching.  The first field of the termcap
264 * entry is a sequence of names separated by |'s, so we compare
265 * against each such name.  The normal : terminator after the last
266 * name (before the first field) stops us.
267 */
268int
269tnamatch(np)
270	char *np;
271{
272	char *Np, *Bp;
273
274	Bp = tbuf;
275	if (*Bp == '#')
276		return (0);
277	for (;;) {
278		for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
279			continue;
280		if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
281			return (1);
282		while (*Bp && *Bp != ':' && *Bp != '|')
283			Bp++;
284		if (*Bp == 0 || *Bp == ':')
285			return (0);
286		Bp++;
287	}
288}
289
290/*
291 * Skip to the next field.  Notice that this is very dumb, not
292 * knowing about \: escapes or any such.  If necessary, :'s can be put
293 * into the termcap file in octal.
294 */
295static char *
296tskip(bp)
297	char *bp;
298{
299	int dquote;
300
301	dquote = 0;
302	while (*bp) {
303		switch (*bp) {
304		case ':':
305			if (!dquote)
306				goto breakbreak;
307			else
308				bp++;
309			break;
310		case '\\':
311			bp++;
312			if (isdigit(*bp)) {
313				while (isdigit(*bp++))
314					;
315			} else
316				bp++;
317		case '"':
318			dquote = (dquote ? 1 : 0);
319			bp++;
320			break;
321		default:
322			bp++;
323			break;
324		}
325	}
326breakbreak:
327	if (*bp == ':')
328		bp++;
329	return (bp);
330}
331
332/*
333 * Return the (numeric) option id.
334 * Numeric options look like
335 *	li#80
336 * i.e. the option string is separated from the numeric value by
337 * a # character.  If the option is not found we return -1.
338 * Note that we handle octal numbers beginning with 0.
339 */
340int64_t
341tgetnum(id)
342	char *id;
343{
344	int64_t i;
345	int base;
346	char *bp = tbuf;
347
348	for (;;) {
349		bp = tskip(bp);
350		if (*bp == 0)
351			return (-1);
352		if (strncmp(bp, id, strlen(id)) != 0)
353			continue;
354		bp += strlen(id);
355		if (*bp == '@')
356			return (-1);
357		if (*bp != '#')
358			continue;
359		bp++;
360		base = 10;
361		if (*bp == '0')
362			base = 8;
363		i = 0;
364		while (isdigit(*bp))
365			i *= base, i += *bp++ - '0';
366		return (i);
367	}
368}
369
370/*
371 * Handle a flag option.
372 * Flag options are given "naked", i.e. followed by a : or the end
373 * of the buffer.  Return 1 if we find the option, or 0 if it is
374 * not given.
375 */
376int
377tgetflag(id)
378	char *id;
379{
380	char *bp = tbuf;
381
382	for (;;) {
383		bp = tskip(bp);
384		if (!*bp)
385			return (0);
386		if (strncmp(bp, id, strlen(id)) == 0) {
387			bp += strlen(id);
388			if (!*bp || *bp == ':')
389				return (1);
390			else if (*bp == '@')
391				return (0);
392		}
393	}
394}
395
396/*
397 * Get a string valued option.
398 * These are given as
399 *	cl=^Z
400 * Much decoding is done on the strings, and the strings are
401 * placed in area, which is a ref parameter which is updated.
402 * No checking on area overflow.
403 */
404char *
405tgetstr(id, area)
406	char *id, **area;
407{
408	char *bp = tbuf;
409
410	for (;;) {
411		bp = tskip(bp);
412		if (!*bp)
413			return (0);
414		if (strncmp(bp, id, strlen(id)) != 0)
415			continue;
416		bp += strlen(id);
417		if (*bp == '@')
418			return (0);
419		if (*bp != '=')
420			continue;
421		bp++;
422		return (tdecode(bp, area));
423	}
424}
425
426/*
427 * Tdecode does the grung work to decode the
428 * string capability escapes.
429 */
430static char *
431tdecode(str, area)
432	char *str;
433	char **area;
434{
435	char *cp;
436	int c;
437	char *dp;
438	int i;
439	char term;
440
441	term = ':';
442	cp = *area;
443again:
444	if (*str == '"') {
445		term = '"';
446		str++;
447	}
448	while ((c = *str++) && c != term) {
449		switch (c) {
450
451		case '^':
452			c = *str++ & 037;
453			break;
454
455		case '\\':
456			dp = "E\033^^\\\\::n\nr\rt\tb\bf\f\"\"";
457			c = *str++;
458nextc:
459			if (*dp++ == c) {
460				c = *dp++;
461				break;
462			}
463			dp++;
464			if (*dp)
465				goto nextc;
466			if (isdigit(c)) {
467				c -= '0', i = 2;
468				do
469					c <<= 3, c |= *str++ - '0';
470				while (--i && isdigit(*str));
471			}
472			break;
473		}
474		*cp++ = c;
475	}
476	if (c == term && term != ':') {
477		term = ':';
478		goto again;
479	}
480	*cp++ = 0;
481	str = *area;
482	*area = cp;
483	return (str);
484}
485