xref: /netbsd-src/usr.sbin/fstyp/ufs.c (revision 87ba0e2a319653af510fae24a6d2975d3589735b)
1 /*	$NetBSD: ufs.c,v 1.2 2022/11/17 06:40:40 chs Exp $	*/
2 
3 /*-
4  * Copyright (c) 2017 The NetBSD Foundation, Inc.
5  * Copyright (c) 2016 The DragonFly Project
6  * Copyright (c) 2002, 2003 Gordon Tetlow
7  * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
8  * Copyright (c) 2014 The FreeBSD Foundation
9  * All rights reserved.
10  *
11  * This code is derived from software contributed to The NetBSD Foundation
12  * by Tomohiro Kusumi <kusumi.tomohiro@gmail.com>.
13  *
14  * This software was developed by Edward Tomasz Napierala under sponsorship
15  * from the FreeBSD Foundation.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 #include <sys/cdefs.h>
39 __RCSID("$NetBSD: ufs.c,v 1.2 2022/11/17 06:40:40 chs Exp $");
40 
41 #include <sys/types.h>
42 #include <stdint.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 
47 #include <ufs/ffs/fs.h>
48 
49 #include "fstyp.h"
50 
51 static const int superblocks[] = SBLOCKSEARCH;
52 
53 int
fstyp_ufs(FILE * fp,char * label,size_t labelsize)54 fstyp_ufs(FILE *fp, char *label, size_t labelsize)
55 {
56 	int sb, superblock;
57 	struct fs *fs;
58 
59 	/*
60 	 * Walk through the standard places that superblocks hide and look
61 	 * for UFS magic. If we find magic, then check that the size in the
62 	 * superblock corresponds to the size of the underlying provider.
63 	 * Finally, look for a volume label and create an appropriate
64 	 * provider based on that.
65 	 */
66 	for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
67 		fs = (struct fs *)read_buf(fp, superblock, SBLOCKSIZE);
68 		if (fs == NULL)
69 			continue;
70 
71 		if (fs->fs_magic == FS_UFS2EA_MAGIC)
72 			fs->fs_magic = FS_UFS2_MAGIC;
73 		else if (fs->fs_magic == FS_UFS2EA_MAGIC_SWAPPED)
74 			fs->fs_magic = FS_UFS2_MAGIC_SWAPPED;
75 
76 		/*
77 		 * Check for magic. We also need to check if file system size
78 		 * is equal to providers size, because sysinstall(8) used to
79 		 * bogusly put first partition at offset 0 instead of 16, and
80 		 * glabel/ufs would find file system on slice instead of
81 		 * partition.
82 		 */
83 #ifdef notyet
84 		if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0 &&
85 		    ((pp->mediasize / fs->fs_fsize == fs->fs_old_size) ||
86 		    (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
87 		    	/* Valid UFS1. */
88 		} else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0 &&
89 		    ((pp->mediasize / fs->fs_fsize == fs->fs_size) ||
90 		    (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
91 		    	/* Valid UFS2. */
92 		} else {
93 			g_free(fs);
94 			continue;
95 		}
96 #else
97 		if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0) {
98 		    	/* Valid UFS1. */
99 		} else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0) {
100 		    	/* Valid UFS2. */
101 		} else {
102 			free(fs);
103 			continue;
104 		}
105 #endif
106 
107 		if (fs->fs_sblockloc != superblock || fs->fs_ncg < 1 ||
108 		    fs->fs_bsize < MINBSIZE ||
109 		    (size_t)fs->fs_bsize < sizeof(struct fs)) {
110 			free(fs);
111 			continue;
112 		}
113 
114 		strlcpy(label, (char*)fs->fs_volname, labelsize);
115 
116 		free(fs);
117 		return 0;
118 	}
119 
120 	return 1;
121 }
122