1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2014 Juniper Networks, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #include <sys/errno.h>
31 #include <stdint.h>
32 #include <stdlib.h>
33 #include <string.h>
34
35 #include <mbr.h>
36
37 #include "endian.h"
38 #include "image.h"
39 #include "mkimg.h"
40 #include "scheme.h"
41
42 static struct mkimg_alias ebr_aliases[] = {
43 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16) },
44 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) },
45 { ALIAS_FAT32LBA, ALIAS_INT2TYPE(DOSPTYP_FAT32LBA) },
46 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) },
47 { ALIAS_NONE, 0 }
48 };
49
50 static lba_t
ebr_metadata(u_int where,lba_t blk)51 ebr_metadata(u_int where, lba_t blk)
52 {
53
54 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0;
55 return (round_track(blk));
56 }
57
58 static void
ebr_chs(u_char * cylp,u_char * hdp,u_char * secp,lba_t lba)59 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba)
60 {
61 u_int cyl, hd, sec;
62
63 mkimg_chs(lba, 1023, &cyl, &hd, &sec);
64 *cylp = cyl;
65 *hdp = hd;
66 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
67 }
68
69 static int
ebr_write(lba_t imgsz __unused,void * bootcode __unused)70 ebr_write(lba_t imgsz __unused, void *bootcode __unused)
71 {
72 u_char *ebr;
73 struct dos_partition *dp;
74 struct part *part, *next;
75 lba_t block, size;
76 int error;
77
78 ebr = malloc(secsz);
79 if (ebr == NULL)
80 return (ENOMEM);
81 memset(ebr, 0, secsz);
82 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC);
83
84 error = 0;
85 TAILQ_FOREACH(part, &partlist, link) {
86 block = part->block - nsecs;
87 size = round_track(part->size);
88 dp = (void *)(ebr + DOSPARTOFF);
89 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs);
90 dp->dp_typ = ALIAS_TYPE2INT(part->type);
91 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
92 part->block + size - 1);
93 le32enc(&dp->dp_start, nsecs);
94 le32enc(&dp->dp_size, size);
95
96 /* Add link entry */
97 next = TAILQ_NEXT(part, link);
98 if (next != NULL) {
99 size = round_track(next->size);
100 dp++;
101 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect,
102 next->block - nsecs);
103 dp->dp_typ = DOSPTYP_EXT;
104 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
105 next->block + size - 1);
106 le32enc(&dp->dp_start, next->block - nsecs);
107 le32enc(&dp->dp_size, size + nsecs);
108 }
109
110 error = image_write(block, ebr, 1);
111 if (error)
112 break;
113
114 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE);
115 }
116
117 free(ebr);
118 return (error);
119 }
120
121 static struct mkimg_scheme ebr_scheme = {
122 .name = "ebr",
123 .description = "Extended Boot Record",
124 .aliases = ebr_aliases,
125 .metadata = ebr_metadata,
126 .write = ebr_write,
127 .nparts = 4096,
128 .maxsecsz = 4096
129 };
130
131 SCHEME_DEFINE(ebr_scheme);
132