1/*-
2 * Copyright (c) 2014 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Edward Tomasz Napierala under sponsorship
6 * from the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD$");
33
34#include <sys/capsicum.h>
35#include <sys/disk.h>
36#include <sys/ioctl.h>
37#include <sys/stat.h>
38#include <capsicum_helpers.h>
39#include <err.h>
40#include <errno.h>
41#ifdef WITH_ICONV
42#include <iconv.h>
43#endif
44#include <locale.h>
45#include <stdbool.h>
46#include <stddef.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50#include <unistd.h>
51#include <vis.h>
52
53#include "fstyp.h"
54
55#define	LABEL_LEN	256
56
57bool show_label = false;
58
59typedef int (*fstyp_function)(FILE *, char *, size_t);
60
61static struct {
62	const char	*name;
63	fstyp_function	function;
64	bool		unmountable;
65	char		*precache_encoding;
66} fstypes[] = {
67	{ "cd9660", &fstyp_cd9660, false, NULL },
68	{ "exfat", &fstyp_exfat, false, EXFAT_ENC },
69	{ "ext2fs", &fstyp_ext2fs, false, NULL },
70	{ "geli", &fstyp_geli, true, NULL },
71	{ "msdosfs", &fstyp_msdosfs, false, NULL },
72	{ "ntfs", &fstyp_ntfs, false, NULL },
73	{ "ufs", &fstyp_ufs, false, NULL },
74#ifdef HAVE_ZFS
75	{ "zfs", &fstyp_zfs, true, NULL },
76#endif
77	{ NULL, NULL, NULL, NULL }
78};
79
80void *
81read_buf(FILE *fp, off_t off, size_t len)
82{
83	int error;
84	size_t nread;
85	void *buf;
86
87	error = fseek(fp, off, SEEK_SET);
88	if (error != 0) {
89		warn("cannot seek to %jd", (uintmax_t)off);
90		return (NULL);
91	}
92
93	buf = malloc(len);
94	if (buf == NULL) {
95		warn("cannot malloc %zd bytes of memory", len);
96		return (NULL);
97	}
98
99	nread = fread(buf, len, 1, fp);
100	if (nread != 1) {
101		free(buf);
102		if (feof(fp) == 0)
103			warn("fread");
104		return (NULL);
105	}
106
107	return (buf);
108}
109
110char *
111checked_strdup(const char *s)
112{
113	char *c;
114
115	c = strdup(s);
116	if (c == NULL)
117		err(1, "strdup");
118	return (c);
119}
120
121void
122rtrim(char *label, size_t size)
123{
124	ptrdiff_t i;
125
126	for (i = size - 1; i >= 0; i--) {
127		if (label[i] == '\0')
128			continue;
129		else if (label[i] == ' ')
130			label[i] = '\0';
131		else
132			break;
133	}
134}
135
136static void
137usage(void)
138{
139
140	fprintf(stderr, "usage: fstyp [-l] [-s] [-u] special\n");
141	exit(1);
142}
143
144static void
145type_check(const char *path, FILE *fp)
146{
147	int error, fd;
148	off_t mediasize;
149	struct stat sb;
150
151	fd = fileno(fp);
152
153	error = fstat(fd, &sb);
154	if (error != 0)
155		err(1, "%s: fstat", path);
156
157	if (S_ISREG(sb.st_mode))
158		return;
159
160	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
161	if (error != 0)
162		errx(1, "%s: not a disk", path);
163}
164
165int
166main(int argc, char **argv)
167{
168	int ch, error, i, nbytes;
169	bool ignore_type = false, show_unmountable = false;
170	char label[LABEL_LEN + 1], strvised[LABEL_LEN * 4 + 1];
171	char *path;
172	FILE *fp;
173	fstyp_function fstyp_f;
174
175	while ((ch = getopt(argc, argv, "lsu")) != -1) {
176		switch (ch) {
177		case 'l':
178			show_label = true;
179			break;
180		case 's':
181			ignore_type = true;
182			break;
183		case 'u':
184			show_unmountable = true;
185			break;
186		default:
187			usage();
188		}
189	}
190
191	argc -= optind;
192	argv += optind;
193	if (argc != 1)
194		usage();
195
196	path = argv[0];
197
198	if (setlocale(LC_CTYPE, "") == NULL)
199		err(1, "setlocale");
200	caph_cache_catpages();
201
202#ifdef WITH_ICONV
203	/* Cache iconv conversion data before entering capability mode. */
204	if (show_label) {
205		for (i = 0; i < nitems(fstypes); i++) {
206			iconv_t cd;
207
208			if (fstypes[i].precache_encoding == NULL)
209				continue;
210			cd = iconv_open("", fstypes[i].precache_encoding);
211			if (cd == (iconv_t)-1)
212				err(1, "%s: iconv_open %s", fstypes[i].name,
213				    fstypes[i].precache_encoding);
214			/* Iconv keeps a small cache of unused encodings. */
215			iconv_close(cd);
216		}
217	}
218#endif
219
220	fp = fopen(path, "r");
221	if (fp == NULL)
222		err(1, "%s", path);
223
224	if (caph_enter() < 0)
225		err(1, "cap_enter");
226
227	if (ignore_type == false)
228		type_check(path, fp);
229
230	memset(label, '\0', sizeof(label));
231
232	for (i = 0;; i++) {
233		if (show_unmountable == false && fstypes[i].unmountable == true)
234			continue;
235		fstyp_f = fstypes[i].function;
236		if (fstyp_f == NULL)
237			break;
238
239		error = fstyp_f(fp, label, sizeof(label));
240		if (error == 0)
241			break;
242	}
243
244	if (fstypes[i].name == NULL) {
245		warnx("%s: filesystem not recognized", path);
246		return (1);
247	}
248
249	if (show_label && label[0] != '\0') {
250		/*
251		 * XXX: I'd prefer VIS_HTTPSTYLE, but it unconditionally
252		 *      encodes spaces.
253		 */
254		nbytes = strsnvis(strvised, sizeof(strvised), label,
255		    VIS_GLOB | VIS_NL, "\"'$");
256		if (nbytes == -1)
257			err(1, "strsnvis");
258
259		printf("%s %s\n", fstypes[i].name, strvised);
260	} else {
261		printf("%s\n", fstypes[i].name);
262	}
263
264	return (0);
265}
266