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