xref: /freebsd/usr.sbin/fstyp/hammer.c (revision cd0d51baaa4509a1db83251a601d34404d20c990)
1 /*-
2  * Copyright (c) 2016 The DragonFly Project
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 AUTHORS 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 AUTHORS 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 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <err.h>
37 #include <assert.h>
38 
39 #include <sys/types.h>
40 
41 #include "hammer_disk.h"
42 
43 #include "fstyp.h"
44 
45 static hammer_volume_ondisk_t
46 __read_ondisk(FILE *fp)
47 {
48 	hammer_volume_ondisk_t ondisk;
49 
50 	ondisk = read_buf(fp, 0, sizeof(*ondisk));
51 	if (ondisk == NULL)
52 		err(1, "failed to read ondisk");
53 
54 	return (ondisk);
55 }
56 
57 static int
58 __test_ondisk(const hammer_volume_ondisk_t ondisk)
59 {
60 	static int count = 0;
61 	static hammer_uuid_t fsid, fstype;
62 	static char label[64];
63 
64 	if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME &&
65 	    ondisk->vol_signature != HAMMER_FSBUF_VOLUME_REV)
66 		return (1);
67 	if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO)
68 		return (2);
69 	if (ondisk->vol_no < 0 || ondisk->vol_no > HAMMER_MAX_VOLUMES - 1)
70 		return (3);
71 	if (ondisk->vol_count < 1 || ondisk->vol_count > HAMMER_MAX_VOLUMES)
72 		return (4);
73 
74 	if (count == 0) {
75 		count = ondisk->vol_count;
76 		assert(count != 0);
77 		memcpy(&fsid, &ondisk->vol_fsid, sizeof(fsid));
78 		memcpy(&fstype, &ondisk->vol_fstype, sizeof(fstype));
79 		strncpy(label, ondisk->vol_label, sizeof(label));
80 	} else {
81 		if (ondisk->vol_count != count)
82 			return (5);
83 		if (memcmp(&ondisk->vol_fsid, &fsid, sizeof(fsid)))
84 			return (6);
85 		if (memcmp(&ondisk->vol_fstype, &fstype, sizeof(fstype)))
86 			return (7);
87 		if (strncmp(ondisk->vol_label, label, sizeof(label)))
88 			return (8);
89 	}
90 
91 	return (0);
92 }
93 
94 int
95 fstyp_hammer(FILE *fp, char *label, size_t size)
96 {
97 	hammer_volume_ondisk_t ondisk;
98 	int error = 1;
99 
100 	ondisk = __read_ondisk(fp);
101 	if (ondisk->vol_no != HAMMER_ROOT_VOLNO)
102 		goto done;
103 	if (ondisk->vol_count != 1)
104 		goto done;
105 	if (__test_ondisk(ondisk))
106 		goto done;
107 
108 	strlcpy(label, ondisk->vol_label, size);
109 	error = 0;
110 done:
111 	free(ondisk);
112 	return (error);
113 }
114 
115 static int
116 __test_volume(const char *volpath)
117 {
118 	hammer_volume_ondisk_t ondisk;
119 	FILE *fp;
120 	int volno = -1;
121 
122 	if ((fp = fopen(volpath, "r")) == NULL)
123 		err(1, "failed to open %s", volpath);
124 
125 	ondisk = __read_ondisk(fp);
126 	fclose(fp);
127 	if (__test_ondisk(ondisk))
128 		goto done;
129 
130 	volno = ondisk->vol_no;
131 done:
132 	free(ondisk);
133 	return (volno);
134 }
135 
136 static int
137 __fsvtyp_hammer(const char *blkdevs, char *label, size_t size, int partial)
138 {
139 	hammer_volume_ondisk_t ondisk;
140 	FILE *fp;
141 	char *dup, *p, *volpath, x[HAMMER_MAX_VOLUMES];
142 	int i, volno, error = 1;
143 
144 	memset(x, 0, sizeof(x));
145 	dup = strdup(blkdevs);
146 	p = dup;
147 
148 	while (p) {
149 		volpath = p;
150 		if ((p = strchr(p, ':')) != NULL)
151 			*p++ = '\0';
152 		if ((volno = __test_volume(volpath)) == -1)
153 			break;
154 		x[volno]++;
155 	}
156 
157 	if ((fp = fopen(volpath, "r")) == NULL)
158 		err(1, "failed to open %s", volpath);
159 	ondisk = __read_ondisk(fp);
160 	fclose(fp);
161 
162 	free(dup);
163 
164 	if (volno == -1)
165 		goto done;
166 	if (partial)
167 		goto success;
168 
169 	for (i = 0; i < HAMMER_MAX_VOLUMES; i++)
170 		if (x[i] > 1)
171 			goto done;
172 	for (i = 0; i < HAMMER_MAX_VOLUMES; i++)
173 		if (x[i] == 0)
174 			break;
175 	if (ondisk->vol_count != i)
176 		goto done;
177 	for (; i < HAMMER_MAX_VOLUMES; i++)
178 		if (x[i] != 0)
179 			goto done;
180 success:
181 	strlcpy(label, ondisk->vol_label, size);
182 	error = 0;
183 done:
184 	free(ondisk);
185 	return (error);
186 }
187 
188 int
189 fsvtyp_hammer(const char *blkdevs, char *label, size_t size)
190 {
191 	return (__fsvtyp_hammer(blkdevs, label, size, 0));
192 }
193 
194 int
195 fsvtyp_hammer_partial(const char *blkdevs, char *label, size_t size)
196 {
197 	return (__fsvtyp_hammer(blkdevs, label, size, 1));
198 }
199