xref: /freebsd/usr.sbin/fstyp/zfs.c (revision 4b43341deaaec99e74d30752a34ec2418ad40cfc)
1  /*-
2   * Copyright (c) 2015 Allan Jude <allanjude@FreeBSD.org>
3   * Copyright (c) 2015 Xin LI <delphij@FreeBSD.org>
4   * All rights reserved.
5   *
6   * Redistribution and use in source and binary forms, with or without
7   * modification, are permitted provided that the following conditions
8   * are met:
9   * 1. Redistributions of source code must retain the above copyright
10   *    notice, this list of conditions and the following disclaimer.
11   * 2. Redistributions in binary form must reproduce the above copyright
12   *    notice, this list of conditions and the following disclaimer in the
13   *    documentation and/or other materials provided with the distribution.
14   *
15   * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25   * SUCH DAMAGE.
26   */
27  
28  #include <sys/cdefs.h>
29  __FBSDID("$FreeBSD$");
30  
31  #include <sys/types.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  	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