1 /*-
2 * Copyright (c) 2014 Juniper Networks, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
13 *
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
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 #include <sys/errno.h>
29 #include <stdint.h>
30 #include <stdlib.h>
31 #include <string.h>
32
33 #include <mbr.h>
34
35 #include "endian.h"
36 #include "image.h"
37 #include "mkimg.h"
38 #include "scheme.h"
39
40 static struct mkimg_alias ebr_aliases[] = {
41 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16) },
42 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) },
43 { ALIAS_FAT32LBA, ALIAS_INT2TYPE(DOSPTYP_FAT32LBA) },
44 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) },
45 { ALIAS_NONE, 0 }
46 };
47
48 static lba_t
ebr_metadata(u_int where,lba_t blk)49 ebr_metadata(u_int where, lba_t blk)
50 {
51
52 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0;
53 return (round_track(blk));
54 }
55
56 static void
ebr_chs(u_char * cylp,u_char * hdp,u_char * secp,lba_t lba)57 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba)
58 {
59 u_int cyl, hd, sec;
60
61 mkimg_chs(lba, 1023, &cyl, &hd, &sec);
62 *cylp = cyl;
63 *hdp = hd;
64 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
65 }
66
67 static int
ebr_write(lba_t imgsz __unused,void * bootcode __unused)68 ebr_write(lba_t imgsz __unused, void *bootcode __unused)
69 {
70 u_char *ebr;
71 struct dos_partition *dp;
72 struct part *part, *next;
73 lba_t block, size;
74 int error;
75
76 ebr = malloc(secsz);
77 if (ebr == NULL)
78 return (ENOMEM);
79 memset(ebr, 0, secsz);
80 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC);
81
82 error = 0;
83 TAILQ_FOREACH(part, &partlist, link) {
84 block = part->block - nsecs;
85 size = round_track(part->size);
86 dp = (void *)(ebr + DOSPARTOFF);
87 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs);
88 dp->dp_typ = ALIAS_TYPE2INT(part->type);
89 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
90 part->block + size - 1);
91 le32enc(&dp->dp_start, nsecs);
92 le32enc(&dp->dp_size, size);
93
94 /* Add link entry */
95 next = TAILQ_NEXT(part, link);
96 if (next != NULL) {
97 size = round_track(next->size);
98 dp++;
99 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect,
100 next->block - nsecs);
101 dp->dp_typ = DOSPTYP_EXT;
102 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
103 next->block + size - 1);
104 le32enc(&dp->dp_start, next->block - nsecs);
105 le32enc(&dp->dp_size, size + nsecs);
106 }
107
108 error = image_write(block, ebr, 1);
109 if (error)
110 break;
111
112 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE);
113 }
114
115 free(ebr);
116 return (error);
117 }
118
119 static struct mkimg_scheme ebr_scheme = {
120 .name = "ebr",
121 .description = "Extended Boot Record",
122 .aliases = ebr_aliases,
123 .metadata = ebr_metadata,
124 .write = ebr_write,
125 .nparts = 4096,
126 .maxsecsz = 4096
127 };
128
129 SCHEME_DEFINE(ebr_scheme);
130