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/errno.h> 31 #include <stdint.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include <unistd.h> 35 36 #include <mbr.h> 37 38 #include "endian.h" 39 #include "image.h" 40 #include "mkimg.h" 41 #include "scheme.h" 42 43 static struct mkimg_alias ebr_aliases[] = { 44 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16) }, 45 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) }, 46 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) }, 47 { ALIAS_NONE, 0 } 48 }; 49 50 static lba_t 51 ebr_metadata(u_int where, lba_t blk) 52 { 53 54 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0; 55 return (round_track(blk)); 56 } 57 58 static void 59 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba) 60 { 61 u_int cyl, hd, sec; 62 63 mkimg_chs(lba, 1023, &cyl, &hd, &sec); 64 *cylp = cyl; 65 *hdp = hd; 66 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 67 } 68 69 static int 70 ebr_write(lba_t imgsz __unused, void *bootcode __unused) 71 { 72 u_char *ebr; 73 struct dos_partition *dp; 74 struct part *part, *next; 75 lba_t block, size; 76 int error; 77 78 ebr = malloc(secsz); 79 if (ebr == NULL) 80 return (ENOMEM); 81 memset(ebr, 0, secsz); 82 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC); 83 84 error = 0; 85 TAILQ_FOREACH(part, &partlist, link) { 86 block = part->block - nsecs; 87 size = round_track(part->size); 88 dp = (void *)(ebr + DOSPARTOFF); 89 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs); 90 dp->dp_typ = ALIAS_TYPE2INT(part->type); 91 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 92 part->block + size - 1); 93 le32enc(&dp->dp_start, nsecs); 94 le32enc(&dp->dp_size, size); 95 96 /* Add link entry */ 97 next = TAILQ_NEXT(part, link); 98 if (next != NULL) { 99 size = round_track(next->size); 100 dp++; 101 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, 102 next->block - nsecs); 103 dp->dp_typ = DOSPTYP_EXT; 104 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 105 next->block + size - 1); 106 le32enc(&dp->dp_start, next->block - nsecs); 107 le32enc(&dp->dp_size, size + nsecs); 108 } 109 110 error = image_write(block, ebr, 1); 111 if (error) 112 break; 113 114 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE); 115 } 116 117 free(ebr); 118 return (error); 119 } 120 121 static struct mkimg_scheme ebr_scheme = { 122 .name = "ebr", 123 .description = "Extended Boot Record", 124 .aliases = ebr_aliases, 125 .metadata = ebr_metadata, 126 .write = ebr_write, 127 .nparts = 4096, 128 .maxsecsz = 4096 129 }; 130 131 SCHEME_DEFINE(ebr_scheme); 132