2 * Copyright (c) 2014 Juniper Networks, Inc.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/types.h>
31 #include <sys/diskmbr.h>
32 #include <sys/endian.h>
33 #include <sys/errno.h>
42 #ifndef DOSPTYP_FAT16B
43 #define DOSPTYP_FAT16B 0x06
46 #define DOSPTYP_FAT32 0x0b
49 #define DOSPTYP_EFI 0xef
52 static struct mkimg_alias mbr_aliases[] = {
53 { ALIAS_EBR, ALIAS_INT2TYPE(DOSPTYP_EXT) },
54 { ALIAS_EFI, ALIAS_INT2TYPE(DOSPTYP_EFI) },
55 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16B) },
56 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) },
57 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) },
58 { ALIAS_NTFS, ALIAS_INT2TYPE(DOSPTYP_NTFS) },
59 { ALIAS_NONE, 0 } /* Keep last! */
63 mbr_metadata(u_int where, lba_t blk)
66 blk += (where == SCHEME_META_IMG_START) ? 1 : 0;
67 return (round_track(blk));
71 mbr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba)
75 mkimg_chs(lba, 1023, &cyl, &hd, &sec);
78 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
82 mbr_write(lba_t imgsz __unused, void *bootcode)
85 struct dos_partition *dpbase, *dp;
93 if (bootcode != NULL) {
94 memcpy(mbr, bootcode, DOSPARTOFF);
95 memset(mbr + DOSPARTOFF, 0, secsz - DOSPARTOFF);
97 memset(mbr, 0, secsz);
98 le16enc(mbr + DOSMAGICOFFSET, DOSMAGIC);
99 dpbase = (void *)(mbr + DOSPARTOFF);
100 STAILQ_FOREACH(part, &partlist, link) {
101 size = round_track(part->size);
102 dp = dpbase + part->index;
103 dp->dp_flag = (part->index == 0 && bootcode != NULL) ? 0x80 : 0;
104 mbr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect,
106 dp->dp_typ = ALIAS_TYPE2INT(part->type);
107 mbr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
108 part->block + size - 1);
109 le32enc(&dp->dp_start, part->block);
110 le32enc(&dp->dp_size, size);
112 error = image_write(0, mbr, 1);
117 static struct mkimg_scheme mbr_scheme = {
119 .description = "Master Boot Record",
120 .aliases = mbr_aliases,
121 .metadata = mbr_metadata,
128 SCHEME_DEFINE(mbr_scheme);