xref: /dragonfly/usr.sbin/fstyp/hammer2.c (revision 7c4f4eee)
1 /*-
2  * Copyright (c) 2017-2019 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 <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <err.h>
34 #include <vfs/hammer2/hammer2_disk.h>
35 
36 #include "fstyp.h"
37 
38 static hammer2_volume_data_t*
39 __read_voldata(FILE *fp)
40 {
41 	hammer2_volume_data_t *voldata;
42 
43 	voldata = read_buf(fp, 0, sizeof(*voldata));
44 	if (voldata == NULL)
45 		err(1, "failed to read volume data");
46 
47 	return (voldata);
48 }
49 
50 static int
51 __test_voldata(const hammer2_volume_data_t *voldata)
52 {
53 	if (voldata->magic != HAMMER2_VOLUME_ID_HBO &&
54 	    voldata->magic != HAMMER2_VOLUME_ID_ABO)
55 		return (1);
56 
57 	return (0);
58 }
59 
60 static int
61 __read_label(FILE *fp, char *label, size_t size)
62 {
63 	hammer2_blockref_t broot, best, *bref;
64 	hammer2_media_data_t *vols[HAMMER2_NUM_VOLHDRS], *media;
65 	hammer2_off_t io_off, io_base;
66 	size_t bytes, io_bytes, boff;
67 	int i, best_i, error = 0;
68 
69 	best_i = -1;
70 	memset(&best, 0, sizeof(best));
71 
72 	for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++) {
73 		memset(&broot, 0, sizeof(broot));
74 		broot.type = HAMMER2_BREF_TYPE_VOLUME;
75 		broot.data_off = (i * HAMMER2_ZONE_BYTES64) | HAMMER2_PBUFRADIX;
76 		vols[i] = read_buf(fp, broot.data_off & ~HAMMER2_OFF_MASK_RADIX,
77 		    sizeof(*vols[i]));
78 		broot.mirror_tid = vols[i]->voldata.mirror_tid;
79 		if (best_i < 0 || best.mirror_tid < broot.mirror_tid) {
80 			best_i = i;
81 			best = broot;
82 		}
83 	}
84 	if (best_i == -1) {
85 		warnx("Failed to find volume header from zones");
86 		error = 1;
87 		goto done;
88 	}
89 
90 	bref = &vols[best_i]->voldata.sroot_blockset.blockref[0];
91 	if (bref->type != HAMMER2_BREF_TYPE_INODE) {
92 		warnx("Superroot blockref type is not inode");
93 		error = 2;
94 		goto done;
95 	}
96 
97 	bytes = bref->data_off & HAMMER2_OFF_MASK_RADIX;
98 	if (bytes)
99 		bytes = (size_t)1 << bytes;
100 	if (bytes != sizeof(hammer2_inode_data_t)) {
101 		warnx("Superroot blockref size does not match inode size");
102 		error = 3;
103 		goto done;
104 	}
105 
106 	io_off = bref->data_off & ~HAMMER2_OFF_MASK_RADIX;
107 	io_base = io_off & ~(hammer2_off_t)(HAMMER2_MINIOSIZE - 1);
108 	boff = io_off - io_base;
109 
110 	io_bytes = HAMMER2_MINIOSIZE;
111 	while (io_bytes + boff < bytes)
112 		io_bytes <<= 1;
113 	if (io_bytes > sizeof(*media)) {
114 		warnx("Invalid I/O bytes");
115 		error = 4;
116 		goto done;
117 	}
118 
119 	media = read_buf(fp, io_base, io_bytes);
120 	if (boff)
121 		memcpy(media, (char*)media + boff, bytes);
122 
123 	strlcpy(label, (char*)media->ipdata.filename, size);
124 	free(media);
125 done:
126 	for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++)
127 		free(vols[i]);
128 
129 	return (error);
130 }
131 
132 int
133 fstyp_hammer2(FILE *fp, char *label, size_t size)
134 {
135 	hammer2_volume_data_t *voldata;
136 	int error = 1;
137 
138 	voldata = __read_voldata(fp);
139 	if (__test_voldata(voldata))
140 		goto done;
141 
142 	error = __read_label(fp, label, size);
143 done:
144 	free(voldata);
145 	return (error);
146 }
147