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/capability.h>
35#include <sys/disk.h>
36#include <sys/ioctl.h>
37#include <sys/stat.h>
38#include <err.h>
39#include <errno.h>
40#include <stdbool.h>
41#include <stddef.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45#include <unistd.h>
46#include <vis.h>
47
48#include "fstyp.h"
49
50#define	LABEL_LEN	256
51
52typedef int (*fstyp_function)(FILE *, char *, size_t);
53
54static struct {
55	const char	*name;
56	fstyp_function	function;
57	bool		unmountable;
58} fstypes[] = {
59	{ "cd9660", &fstyp_cd9660, false },
60	{ "ext2fs", &fstyp_ext2fs, false },
61	{ "geli", &fstyp_geli, true },
62	{ "msdosfs", &fstyp_msdosfs, false },
63	{ "ntfs", &fstyp_ntfs, false },
64	{ "ufs", &fstyp_ufs, false },
65#ifdef HAVE_ZFS
66	{ "zfs", &fstyp_zfs, true },
67#endif
68	{ NULL, NULL, NULL }
69};
70
71void *
72read_buf(FILE *fp, off_t off, size_t len)
73{
74	int error;
75	size_t nread;
76	void *buf;
77
78	error = fseek(fp, off, SEEK_SET);
79	if (error != 0) {
80		warn("cannot seek to %jd", (uintmax_t)off);
81		return (NULL);
82	}
83
84	buf = malloc(len);
85	if (buf == 0) {
86		warn("cannot malloc %zd bytes of memory", len);
87		return (NULL);
88	}
89
90	nread = fread(buf, len, 1, fp);
91	if (nread != 1) {
92		free(buf);
93		if (feof(fp) == 0)
94			warn("fread");
95		return (NULL);
96	}
97
98	return (buf);
99}
100
101char *
102checked_strdup(const char *s)
103{
104	char *c;
105
106	c = strdup(s);
107	if (c == NULL)
108		err(1, "strdup");
109	return (c);
110}
111
112void
113rtrim(char *label, size_t size)
114{
115	ptrdiff_t i;
116
117	for (i = size - 1; i >= 0; i--) {
118		if (label[i] == '\0')
119			continue;
120		else if (label[i] == ' ')
121			label[i] = '\0';
122		else
123			break;
124	}
125}
126
127static void
128usage(void)
129{
130
131	fprintf(stderr, "usage: fstyp [-l] [-s] [-u] special\n");
132	exit(1);
133}
134
135static void
136type_check(const char *path, FILE *fp)
137{
138	int error, fd;
139	off_t mediasize;
140	struct stat sb;
141
142	fd = fileno(fp);
143
144	error = fstat(fd, &sb);
145	if (error != 0)
146		err(1, "%s: fstat", path);
147
148	if (S_ISREG(sb.st_mode))
149		return;
150
151	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
152	if (error != 0)
153		errx(1, "%s: not a disk", path);
154}
155
156int
157main(int argc, char **argv)
158{
159	int ch, error, i, nbytes;
160	bool ignore_type = false, show_label = false, show_unmountable = false;
161	char label[LABEL_LEN + 1], strvised[LABEL_LEN * 4 + 1];
162	char *path;
163	FILE *fp;
164	fstyp_function fstyp_f;
165
166	while ((ch = getopt(argc, argv, "lsu")) != -1) {
167		switch (ch) {
168		case 'l':
169			show_label = true;
170			break;
171		case 's':
172			ignore_type = true;
173			break;
174		case 'u':
175			show_unmountable = true;
176			break;
177		default:
178			usage();
179		}
180	}
181
182	argc -= optind;
183	argv += optind;
184	if (argc != 1)
185		usage();
186
187	path = argv[0];
188
189	fp = fopen(path, "r");
190	if (fp == NULL)
191		err(1, "%s", path);
192
193	error = cap_enter();
194	if (error != 0 && errno != ENOSYS)
195		err(1, "cap_enter");
196
197	if (ignore_type == false)
198		type_check(path, fp);
199
200	memset(label, '\0', sizeof(label));
201
202	for (i = 0;; i++) {
203		if (show_unmountable == false && fstypes[i].unmountable == true)
204			continue;
205		fstyp_f = fstypes[i].function;
206		if (fstyp_f == NULL)
207			break;
208
209		error = fstyp_f(fp, label, sizeof(label));
210		if (error == 0)
211			break;
212	}
213
214	if (fstypes[i].name == NULL) {
215		warnx("%s: filesystem not recognized", path);
216		return (1);
217	}
218
219	if (show_label && label[0] != '\0') {
220		/*
221		 * XXX: I'd prefer VIS_HTTPSTYLE, but it unconditionally
222		 *      encodes spaces.
223		 */
224		nbytes = strsnvis(strvised, sizeof(strvised), label,
225		    VIS_GLOB | VIS_NL, "\"'$");
226		if (nbytes == -1)
227			err(1, "strsnvis");
228
229		printf("%s %s\n", fstypes[i].name, strvised);
230	} else {
231		printf("%s\n", fstypes[i].name);
232	}
233
234	return (0);
235}
236