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 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 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 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