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_FAT32 43 #define DOSPTYP_FAT32 0x0b 44 #endif 45 46 static struct mkimg_alias ebr_aliases[] = { 47 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) }, 48 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) }, 49 { ALIAS_NONE, 0 } 50 }; 51 52 static lba_t 53 ebr_metadata(u_int where, lba_t blk) 54 { 55 56 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0; 57 return (round_track(blk)); 58 } 59 60 static void 61 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba) 62 { 63 u_int cyl, hd, sec; 64 65 mkimg_chs(lba, 1023, &cyl, &hd, &sec); 66 *cylp = cyl; 67 *hdp = hd; 68 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 69 } 70 71 static int 72 ebr_write(lba_t imgsz __unused, void *bootcode __unused) 73 { 74 u_char *ebr; 75 struct dos_partition *dp; 76 struct part *part, *next; 77 lba_t block, size; 78 int error; 79 80 ebr = malloc(secsz); 81 if (ebr == NULL) 82 return (ENOMEM); 83 memset(ebr, 0, secsz); 84 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC); 85 86 error = 0; 87 STAILQ_FOREACH_SAFE(part, &partlist, link, next) { 88 block = part->block - nsecs; 89 size = round_track(part->size); 90 dp = (void *)(ebr + DOSPARTOFF); 91 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs); 92 dp->dp_typ = ALIAS_TYPE2INT(part->type); 93 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 94 part->block + size - 1); 95 le32enc(&dp->dp_start, nsecs); 96 le32enc(&dp->dp_size, size); 97 98 /* Add link entry */ 99 if (next != NULL) { 100 size = round_track(next->size); 101 dp++; 102 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, 103 next->block - nsecs); 104 dp->dp_typ = DOSPTYP_EXT; 105 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 106 next->block + size - 1); 107 le32enc(&dp->dp_start, next->block - nsecs); 108 le32enc(&dp->dp_size, size + nsecs); 109 } 110 111 error = image_write(block, ebr, 1); 112 if (error) 113 break; 114 115 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE); 116 } 117 118 free(ebr); 119 return (error); 120 } 121 122 static struct mkimg_scheme ebr_scheme = { 123 .name = "ebr", 124 .description = "Extended Boot Record", 125 .aliases = ebr_aliases, 126 .metadata = ebr_metadata, 127 .write = ebr_write, 128 .nparts = 4096, 129 .maxsecsz = 4096 130 }; 131 132 SCHEME_DEFINE(ebr_scheme); 133