xref: /netbsd-src/usr.sbin/fstyp/hammer.c (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1 /*        $NetBSD: hammer.c,v 1.3 2020/01/15 15:30:46 tkusumi Exp $      */
2 
3 /*-
4  * Copyright (c) 2016-2019 The DragonFly Project
5  * Copyright (c) 2016-2019 Tomohiro Kusumi <tkusumi@netbsd.org>
6  * All rights reserved.
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 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: hammer.c,v 1.3 2020/01/15 15:30:46 tkusumi Exp $");
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <err.h>
36 #include <assert.h>
37 
38 #include "fstyp.h"
39 #include "hammer_disk.h"
40 
41 static hammer_volume_ondisk_t
42 read_ondisk(FILE *fp)
43 {
44 	hammer_volume_ondisk_t ondisk;
45 
46 	ondisk = read_buf(fp, 0, sizeof(*ondisk));
47 	if (ondisk == NULL)
48 		err(1, "failed to read ondisk");
49 
50 	return (ondisk);
51 }
52 
53 static int
54 test_ondisk(const hammer_volume_ondisk_t ondisk)
55 {
56 	static int count = 0;
57 	static hammer_uuid_t fsid, fstype;
58 	static char label[64];
59 
60 	if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME &&
61 	    ondisk->vol_signature != HAMMER_FSBUF_VOLUME_REV)
62 		return (1);
63 	if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO)
64 		return (2);
65 	if (ondisk->vol_no < 0 || ondisk->vol_no > HAMMER_MAX_VOLUMES - 1)
66 		return (3);
67 	if (ondisk->vol_count < 1 || ondisk->vol_count > HAMMER_MAX_VOLUMES)
68 		return (4);
69 
70 	if (count == 0) {
71 		count = ondisk->vol_count;
72 		assert(count != 0);
73 		memcpy(&fsid, &ondisk->vol_fsid, sizeof(fsid));
74 		memcpy(&fstype, &ondisk->vol_fstype, sizeof(fstype));
75 		strlcpy(label, ondisk->vol_label, sizeof(label));
76 	} else {
77 		if (ondisk->vol_count != count)
78 			return (5);
79 		if (memcmp(&ondisk->vol_fsid, &fsid, sizeof(fsid)))
80 			return (6);
81 		if (memcmp(&ondisk->vol_fstype, &fstype, sizeof(fstype)))
82 			return (7);
83 		if (strcmp(ondisk->vol_label, label))
84 			return (8);
85 	}
86 
87 	return (0);
88 }
89 
90 int
91 fstyp_hammer(FILE *fp, char *label, size_t size)
92 {
93 	hammer_volume_ondisk_t ondisk;
94 	int error = 1;
95 #ifdef HAS_DEVPATH
96 	const char *p;
97 #endif
98 	ondisk = read_ondisk(fp);
99 	if (ondisk->vol_no != HAMMER_ROOT_VOLNO)
100 		goto fail;
101 	if (ondisk->vol_count != 1)
102 		goto fail;
103 	if (test_ondisk(ondisk))
104 		goto fail;
105 
106 	/*
107 	 * fstyp_function in DragonFly takes an additional devpath argument
108 	 * which doesn't exist in FreeBSD and NetBSD.
109 	 */
110 #ifdef HAS_DEVPATH
111 	/* Add device name to help support multiple autofs -media mounts. */
112 	p = strrchr(devpath, '/');
113 	if (p) {
114 		p++;
115 		if (*p == 0)
116 			strlcpy(label, ondisk->vol_label, size);
117 		else
118 			snprintf(label, size, "%s_%s", ondisk->vol_label, p);
119 	} else
120 		snprintf(label, size, "%s_%s", ondisk->vol_label, devpath);
121 #else
122 	strlcpy(label, ondisk->vol_label, size);
123 #endif
124 	error = 0;
125 fail:
126 	free(ondisk);
127 	return (error);
128 }
129 
130 static int
131 test_volume(const char *volpath)
132 {
133 	hammer_volume_ondisk_t ondisk;
134 	FILE *fp;
135 	int volno = -1;
136 
137 	if ((fp = fopen(volpath, "r")) == NULL)
138 		err(1, "failed to open %s", volpath);
139 
140 	ondisk = read_ondisk(fp);
141 	fclose(fp);
142 	if (test_ondisk(ondisk))
143 		goto fail;
144 
145 	volno = ondisk->vol_no;
146 fail:
147 	free(ondisk);
148 	return (volno);
149 }
150 
151 static int
152 __fsvtyp_hammer(const char *blkdevs, char *label, size_t size, int partial)
153 {
154 	hammer_volume_ondisk_t ondisk = NULL;
155 	FILE *fp;
156 	char *dup, *p, *volpath, x[HAMMER_MAX_VOLUMES];
157 	int i, volno, error = 1;
158 
159 	if (!blkdevs)
160 		goto fail;
161 
162 	memset(x, 0, sizeof(x));
163 	dup = strdup(blkdevs);
164 	p = dup;
165 
166 	volpath = NULL;
167 	volno = -1;
168 	while (p) {
169 		volpath = p;
170 		if ((p = strchr(p, ':')) != NULL)
171 			*p++ = '\0';
172 		if ((volno = test_volume(volpath)) == -1)
173 			break;
174 		assert(volno >= 0);
175 		assert(volno < HAMMER_MAX_VOLUMES);
176 		x[volno]++;
177 	}
178 
179 	if (!volpath)
180 		err(1, "invalid path %s", blkdevs);
181 	if ((fp = fopen(volpath, "r")) == NULL)
182 		err(1, "failed to open %s", volpath);
183 	ondisk = read_ondisk(fp);
184 	fclose(fp);
185 
186 	free(dup);
187 
188 	if (volno == -1)
189 		goto fail;
190 	if (partial)
191 		goto success;
192 
193 	for (i = 0; i < HAMMER_MAX_VOLUMES; i++)
194 		if (x[i] > 1)
195 			goto fail;
196 	for (i = 0; i < HAMMER_MAX_VOLUMES; i++)
197 		if (x[i] == 0)
198 			break;
199 	if (ondisk->vol_count != i)
200 		goto fail;
201 	for (; i < HAMMER_MAX_VOLUMES; i++)
202 		if (x[i] != 0)
203 			goto fail;
204 success:
205 	/* XXX autofs -media mount can't handle multiple mounts */
206 	strlcpy(label, ondisk->vol_label, size);
207 	error = 0;
208 fail:
209 	free(ondisk);
210 	return (error);
211 }
212 
213 int
214 fsvtyp_hammer(const char *blkdevs, char *label, size_t size)
215 {
216 	return (__fsvtyp_hammer(blkdevs, label, size, 0));
217 }
218 
219 int
220 fsvtyp_hammer_partial(const char *blkdevs, char *label, size_t size)
221 {
222 	return (__fsvtyp_hammer(blkdevs, label, size, 1));
223 }
224