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/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/capsicum.h>
34#include <sys/disk.h>
35#include <sys/ioctl.h>
36#include <sys/stat.h>
37#include <capsicum_helpers.h>
38#include <err.h>
39#include <errno.h>
40#ifdef WITH_ICONV
41#include <iconv.h>
42#endif
43#include <locale.h>
44#include <stdbool.h>
45#include <stddef.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#include <unistd.h>
50#include <vis.h>
51
52#include "fstyp.h"
53
54#define	LABEL_LEN	256
55
56bool show_label = false;
57
58typedef int (*fstyp_function)(FILE *, char *, size_t);
59
60static struct {
61	const char	*name;
62	fstyp_function	function;
63	bool		unmountable;
64	char		*precache_encoding;
65} fstypes[] = {
66	{ "apfs", &fstyp_apfs, true, NULL },
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	{ "hammer", &fstyp_hammer, true, NULL },
72	{ "hammer2", &fstyp_hammer2, true, NULL },
73	{ "hfs+", &fstyp_hfsp, false, NULL },
74	{ "msdosfs", &fstyp_msdosfs, false, NULL },
75	{ "ntfs", &fstyp_ntfs, false, NTFS_ENC },
76	{ "ufs", &fstyp_ufs, false, NULL },
77#ifdef HAVE_ZFS
78	{ "zfs", &fstyp_zfs, true, NULL },
79#endif
80	{ NULL, NULL, NULL, NULL }
81};
82
83void *
84read_buf(FILE *fp, off_t off, size_t len)
85{
86	int error;
87	size_t nread;
88	void *buf;
89
90	error = fseek(fp, off, SEEK_SET);
91	if (error != 0) {
92		warn("cannot seek to %jd", (uintmax_t)off);
93		return (NULL);
94	}
95
96	buf = malloc(len);
97	if (buf == NULL) {
98		warn("cannot malloc %zd bytes of memory", len);
99		return (NULL);
100	}
101
102	nread = fread(buf, len, 1, fp);
103	if (nread != 1) {
104		free(buf);
105		if (feof(fp) == 0)
106			warn("fread");
107		return (NULL);
108	}
109
110	return (buf);
111}
112
113char *
114checked_strdup(const char *s)
115{
116	char *c;
117
118	c = strdup(s);
119	if (c == NULL)
120		err(1, "strdup");
121	return (c);
122}
123
124void
125rtrim(char *label, size_t size)
126{
127	ptrdiff_t i;
128
129	for (i = size - 1; i >= 0; i--) {
130		if (label[i] == '\0')
131			continue;
132		else if (label[i] == ' ')
133			label[i] = '\0';
134		else
135			break;
136	}
137}
138
139static void
140usage(void)
141{
142
143	fprintf(stderr, "usage: fstyp [-l] [-s] [-u] special\n");
144	exit(1);
145}
146
147static void
148type_check(const char *path, FILE *fp)
149{
150	int error, fd;
151	off_t mediasize;
152	struct stat sb;
153
154	fd = fileno(fp);
155
156	error = fstat(fd, &sb);
157	if (error != 0)
158		err(1, "%s: fstat", path);
159
160	if (S_ISREG(sb.st_mode))
161		return;
162
163	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
164	if (error != 0)
165		errx(1, "%s: not a disk", path);
166}
167
168int
169main(int argc, char **argv)
170{
171	int ch, error, i, nbytes;
172	bool ignore_type = false, show_unmountable = false;
173	char label[LABEL_LEN + 1], strvised[LABEL_LEN * 4 + 1];
174	char *path;
175	FILE *fp;
176	fstyp_function fstyp_f;
177
178	while ((ch = getopt(argc, argv, "lsu")) != -1) {
179		switch (ch) {
180		case 'l':
181			show_label = true;
182			break;
183		case 's':
184			ignore_type = true;
185			break;
186		case 'u':
187			show_unmountable = true;
188			break;
189		default:
190			usage();
191		}
192	}
193
194	argc -= optind;
195	argv += optind;
196	if (argc != 1)
197		usage();
198
199	path = argv[0];
200
201	if (setlocale(LC_CTYPE, "") == NULL)
202		err(1, "setlocale");
203	caph_cache_catpages();
204
205#ifdef WITH_ICONV
206	/* Cache iconv conversion data before entering capability mode. */
207	if (show_label) {
208		for (i = 0; i < nitems(fstypes); i++) {
209			iconv_t cd;
210
211			if (fstypes[i].precache_encoding == NULL)
212				continue;
213			cd = iconv_open("", fstypes[i].precache_encoding);
214			if (cd == (iconv_t)-1)
215				err(1, "%s: iconv_open %s", fstypes[i].name,
216				    fstypes[i].precache_encoding);
217			/* Iconv keeps a small cache of unused encodings. */
218			iconv_close(cd);
219		}
220	}
221#endif
222
223	fp = fopen(path, "r");
224	if (fp == NULL)
225		err(1, "%s", path);
226
227	if (caph_enter() < 0)
228		err(1, "cap_enter");
229
230	if (ignore_type == false)
231		type_check(path, fp);
232
233	memset(label, '\0', sizeof(label));
234
235	for (i = 0;; i++) {
236		if (show_unmountable == false && fstypes[i].unmountable == true)
237			continue;
238		fstyp_f = fstypes[i].function;
239		if (fstyp_f == NULL)
240			break;
241
242		error = fstyp_f(fp, label, sizeof(label));
243		if (error == 0)
244			break;
245	}
246
247	if (fstypes[i].name == NULL) {
248		warnx("%s: filesystem not recognized", path);
249		return (1);
250	}
251
252	if (show_label && label[0] != '\0') {
253		/*
254		 * XXX: I'd prefer VIS_HTTPSTYLE, but it unconditionally
255		 *      encodes spaces.
256		 */
257		nbytes = strsnvis(strvised, sizeof(strvised), label,
258		    VIS_GLOB | VIS_NL, "\"'$");
259		if (nbytes == -1)
260			err(1, "strsnvis");
261
262		printf("%s %s\n", fstypes[i].name, strvised);
263	} else {
264		printf("%s\n", fstypes[i].name);
265	}
266
267	return (0);
268}
269