xref: /freebsd/usr.sbin/fstyp/ufs.c (revision 39ee7a7a6bdd1557b1c3532abf60d139798ac88b)
1 /*-
2  * Copyright (c) 2002, 2003 Gordon Tetlow
3  * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
4  * Copyright (c) 2014 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * This software was developed by Edward Tomasz Napierala under sponsorship
8  * from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/types.h>
36 #include <stdint.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 
41 #include <ufs/ufs/dinode.h>
42 #include <ufs/ffs/fs.h>
43 
44 #include "fstyp.h"
45 
46 static const int superblocks[] = SBLOCKSEARCH;
47 
48 int
49 fstyp_ufs(FILE *fp, char *label, size_t labelsize)
50 {
51 	int sb, superblock;
52 	struct fs *fs;
53 
54 	/*
55 	 * Walk through the standard places that superblocks hide and look
56 	 * for UFS magic. If we find magic, then check that the size in the
57 	 * superblock corresponds to the size of the underlying provider.
58 	 * Finally, look for a volume label and create an appropriate
59 	 * provider based on that.
60 	 */
61 	for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
62 		fs = (struct fs *)read_buf(fp, superblock, SBLOCKSIZE);
63 		if (fs == NULL)
64 			continue;
65 		/*
66 		 * Check for magic. We also need to check if file system size is equal
67 		 * to providers size, because sysinstall(8) used to bogusly put first
68 		 * partition at offset 0 instead of 16, and glabel/ufs would find file
69 		 * system on slice instead of partition.
70 		 */
71 #ifdef notyet
72 		if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0 &&
73 		    ((pp->mediasize / fs->fs_fsize == fs->fs_old_size) ||
74 		    (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
75 		    	/* Valid UFS1. */
76 		} else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0 &&
77 		    ((pp->mediasize / fs->fs_fsize == fs->fs_size) ||
78 		    (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
79 		    	/* Valid UFS2. */
80 		} else {
81 			g_free(fs);
82 			continue;
83 		}
84 #else
85 		if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0) {
86 		    	/* Valid UFS1. */
87 		} else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0) {
88 		    	/* Valid UFS2. */
89 		} else {
90 			free(fs);
91 			continue;
92 		}
93 #endif
94 
95 		if (fs->fs_sblockloc != superblock || fs->fs_ncg < 1 ||
96 		    fs->fs_bsize < MINBSIZE ||
97 		    (size_t)fs->fs_bsize < sizeof(struct fs)) {
98 			free(fs);
99 			continue;
100 		}
101 
102 		strlcpy(label, fs->fs_volname, labelsize);
103 
104 		free(fs);
105 		return (0);
106 	}
107 
108 	return (1);
109 }
110