xref: /freebsd/usr.sbin/fstyp/zfs.c (revision 089104e0e01f080c9cd45dc5f34c4f636dea4ca7)
1 /*-
2  * Copyright (c) 2015 Allan Jude <allanjude@FreeBSD.org>
3  * Copyright (c) 2015 Xin LI <delphij@FreeBSD.org>
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include <sys/time.h>
32 #include <stdint.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 
38 #include <libnvpair.h>
39 #include <sys/vdev_impl.h>
40 
41 #include "fstyp.h"
42 
43 int
44 fstyp_zfs(FILE *fp, char *label, size_t labelsize)
45 {
46 	vdev_label_t *vdev_label = NULL;
47 	vdev_phys_t *vdev_phys;
48 	const char *zpool_name = NULL;
49 	nvlist_t *config = NULL;
50 	int err = 0;
51 
52 	/*
53 	 * Read in the first ZFS vdev label ("L0"), located at the beginning
54 	 * of the vdev and extract the pool name from it.
55 	 *
56 	 * TODO: the checksum of label should be validated.
57 	 */
58 	vdev_label = (vdev_label_t *)read_buf(fp, 0, sizeof(*vdev_label));
59 	if (vdev_label == NULL)
60 		return (1);
61 
62 	vdev_phys = &(vdev_label->vl_vdev_phys);
63 
64 	if ((nvlist_unpack(vdev_phys->vp_nvlist, sizeof(vdev_phys->vp_nvlist),
65 	    &config, 0)) == 0 &&
66 	    (nvlist_lookup_string(config, "name", &zpool_name) == 0)) {
67 		strlcpy(label, zpool_name, labelsize);
68 	} else
69 		err = 1;
70 
71 	nvlist_free(config);
72 	free(vdev_label);
73 
74 	return (err);
75 }
76