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 __FBSDID("$FreeBSD$"); 29 30 #include <sys/types.h> 31 #include <sys/diskmbr.h> 32 #include <sys/endian.h> 33 #include <sys/errno.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <unistd.h> 37 38 #include "image.h" 39 #include "mkimg.h" 40 #include "scheme.h" 41 42 #ifndef DOSPTYP_FAT16B 43 #define DOSPTYP_FAT16B 0x06 44 #endif 45 #ifndef DOSPTYP_FAT32 46 #define DOSPTYP_FAT32 0x0b 47 #endif 48 49 static struct mkimg_alias ebr_aliases[] = { 50 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16B) }, 51 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) }, 52 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) }, 53 { ALIAS_NONE, 0 } 54 }; 55 56 static lba_t 57 ebr_metadata(u_int where, lba_t blk) 58 { 59 60 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0; 61 return (round_track(blk)); 62 } 63 64 static void 65 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba) 66 { 67 u_int cyl, hd, sec; 68 69 mkimg_chs(lba, 1023, &cyl, &hd, &sec); 70 *cylp = cyl; 71 *hdp = hd; 72 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 73 } 74 75 static int 76 ebr_write(lba_t imgsz __unused, void *bootcode __unused) 77 { 78 u_char *ebr; 79 struct dos_partition *dp; 80 struct part *part, *next; 81 lba_t block, size; 82 int error; 83 84 ebr = malloc(secsz); 85 if (ebr == NULL) 86 return (ENOMEM); 87 memset(ebr, 0, secsz); 88 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC); 89 90 error = 0; 91 STAILQ_FOREACH_SAFE(part, &partlist, link, next) { 92 block = part->block - nsecs; 93 size = round_track(part->size); 94 dp = (void *)(ebr + DOSPARTOFF); 95 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs); 96 dp->dp_typ = ALIAS_TYPE2INT(part->type); 97 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 98 part->block + size - 1); 99 le32enc(&dp->dp_start, nsecs); 100 le32enc(&dp->dp_size, size); 101 102 /* Add link entry */ 103 if (next != NULL) { 104 size = round_track(next->size); 105 dp++; 106 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, 107 next->block - nsecs); 108 dp->dp_typ = DOSPTYP_EXT; 109 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 110 next->block + size - 1); 111 le32enc(&dp->dp_start, next->block - nsecs); 112 le32enc(&dp->dp_size, size + nsecs); 113 } 114 115 error = image_write(block, ebr, 1); 116 if (error) 117 break; 118 119 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE); 120 } 121 122 free(ebr); 123 return (error); 124 } 125 126 static struct mkimg_scheme ebr_scheme = { 127 .name = "ebr", 128 .description = "Extended Boot Record", 129 .aliases = ebr_aliases, 130 .metadata = ebr_metadata, 131 .write = ebr_write, 132 .nparts = 4096, 133 .maxsecsz = 4096 134 }; 135 136 SCHEME_DEFINE(ebr_scheme); 137