1/*-
2 * Copyright (c) 2014 The FreeBSD Foundation
3 *
4 * This software was developed by Edward Tomasz Napierala under sponsorship
5 * from the FreeBSD Foundation.
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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30#include <sys/capsicum.h>
31#include <sys/disk.h>
32#include <sys/ioctl.h>
33#include <sys/stat.h>
34#include <capsicum_helpers.h>
35#include <err.h>
36#include <errno.h>
37#ifdef WITH_ICONV
38#include <iconv.h>
39#endif
40#include <locale.h>
41#include <stdbool.h>
42#include <stddef.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <unistd.h>
47#include <vis.h>
48
49#include "fstyp.h"
50
51#define	LABEL_LEN	256
52
53bool show_label = false;
54
55typedef int (*fstyp_function)(FILE *, char *, size_t);
56
57static struct {
58	const char	*name;
59	fstyp_function	function;
60	bool		unmountable;
61	const char	*precache_encoding;
62} fstypes[] = {
63	{ "apfs", &fstyp_apfs, true, NULL },
64	{ "befs", &fstyp_befs, false, NULL },
65	{ "cd9660", &fstyp_cd9660, false, NULL },
66	{ "exfat", &fstyp_exfat, false, EXFAT_ENC },
67	{ "ext2fs", &fstyp_ext2fs, false, NULL },
68	{ "geli", &fstyp_geli, true, NULL },
69	{ "hammer", &fstyp_hammer, true, NULL },
70	{ "hammer2", &fstyp_hammer2, true, NULL },
71	{ "hfs+", &fstyp_hfsp, false, NULL },
72	{ "msdosfs", &fstyp_msdosfs, false, NULL },
73	{ "ntfs", &fstyp_ntfs, false, NTFS_ENC },
74	{ "ufs", &fstyp_ufs, false, NULL },
75#ifdef HAVE_ZFS
76	{ "zfs", &fstyp_zfs, true, NULL },
77#endif
78	{ NULL, NULL, NULL, NULL }
79};
80
81void *
82read_buf(FILE *fp, off_t off, size_t len)
83{
84	int error;
85	size_t nread;
86	void *buf;
87
88	error = fseek(fp, off, SEEK_SET);
89	if (error != 0) {
90		warn("cannot seek to %jd", (uintmax_t)off);
91		return (NULL);
92	}
93
94	buf = malloc(len);
95	if (buf == NULL) {
96		warn("cannot malloc %zd bytes of memory", len);
97		return (NULL);
98	}
99
100	nread = fread(buf, len, 1, fp);
101	if (nread != 1) {
102		free(buf);
103		if (feof(fp) == 0)
104			warn("fread");
105		return (NULL);
106	}
107
108	return (buf);
109}
110
111char *
112checked_strdup(const char *s)
113{
114	char *c;
115
116	c = strdup(s);
117	if (c == NULL)
118		err(1, "strdup");
119	return (c);
120}
121
122void
123rtrim(char *label, size_t size)
124{
125	ptrdiff_t i;
126
127	for (i = size - 1; i >= 0; i--) {
128		if (label[i] == '\0')
129			continue;
130		else if (label[i] == ' ')
131			label[i] = '\0';
132		else
133			break;
134	}
135}
136
137static void
138usage(void)
139{
140
141	fprintf(stderr, "usage: fstyp [-l] [-s] [-u] special\n");
142	exit(1);
143}
144
145static void
146type_check(const char *path, FILE *fp)
147{
148	int error, fd;
149	off_t mediasize;
150	struct stat sb;
151
152	fd = fileno(fp);
153
154	error = fstat(fd, &sb);
155	if (error != 0)
156		err(1, "%s: fstat", path);
157
158	if (S_ISREG(sb.st_mode))
159		return;
160
161	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
162	if (error != 0)
163		errx(1, "%s: not a disk", path);
164}
165
166int
167main(int argc, char **argv)
168{
169	int ch, error, i, nbytes;
170	bool ignore_type = false, show_unmountable = false;
171	char label[LABEL_LEN + 1], strvised[LABEL_LEN * 4 + 1];
172	char *path;
173	FILE *fp;
174	fstyp_function fstyp_f;
175
176	while ((ch = getopt(argc, argv, "lsu")) != -1) {
177		switch (ch) {
178		case 'l':
179			show_label = true;
180			break;
181		case 's':
182			ignore_type = true;
183			break;
184		case 'u':
185			show_unmountable = true;
186			break;
187		default:
188			usage();
189		}
190	}
191
192	argc -= optind;
193	argv += optind;
194	if (argc != 1)
195		usage();
196
197	path = argv[0];
198
199	if (setlocale(LC_CTYPE, "") == NULL)
200		err(1, "setlocale");
201	caph_cache_catpages();
202
203#ifdef WITH_ICONV
204	/* Cache iconv conversion data before entering capability mode. */
205	if (show_label) {
206		for (i = 0; i < (int)nitems(fstypes); i++) {
207			iconv_t cd;
208
209			if (fstypes[i].precache_encoding == NULL)
210				continue;
211			cd = iconv_open("", fstypes[i].precache_encoding);
212			if (cd == (iconv_t)-1)
213				err(1, "%s: iconv_open %s", fstypes[i].name,
214				    fstypes[i].precache_encoding);
215			/* Iconv keeps a small cache of unused encodings. */
216			iconv_close(cd);
217		}
218	}
219#endif
220
221	fp = fopen(path, "r");
222	if (fp == NULL)
223		err(1, "%s", path);
224
225	if (caph_enter() < 0)
226		err(1, "cap_enter");
227
228	if (ignore_type == false)
229		type_check(path, fp);
230
231	memset(label, '\0', sizeof(label));
232
233	for (i = 0;; i++) {
234		if (show_unmountable == false && fstypes[i].unmountable == true)
235			continue;
236		fstyp_f = fstypes[i].function;
237		if (fstyp_f == NULL)
238			break;
239
240		error = fstyp_f(fp, label, sizeof(label));
241		if (error == 0)
242			break;
243	}
244
245	if (fstypes[i].name == NULL) {
246		warnx("%s: filesystem not recognized", path);
247		return (1);
248	}
249
250	if (show_label && label[0] != '\0') {
251		/*
252		 * XXX: I'd prefer VIS_HTTPSTYLE, but it unconditionally
253		 *      encodes spaces.
254		 */
255		nbytes = strsnvis(strvised, sizeof(strvised), label,
256		    VIS_GLOB | VIS_NL, "\"'$");
257		if (nbytes == -1)
258			err(1, "strsnvis");
259
260		printf("%s %s\n", fstypes[i].name, strvised);
261	} else {
262		printf("%s\n", fstypes[i].name);
263	}
264
265	return (0);
266}
267