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 #ifndef DOSPTYP_PPCBOOT 49 #define DOSPTYP_PPCBOOT 0x41 50 #endif 51 #ifndef DOSPTYP_EFI 52 #define DOSPTYP_EFI 0xef 53 #endif 54 55 static struct mkimg_alias mbr_aliases[] = { 56 { ALIAS_EBR, ALIAS_INT2TYPE(DOSPTYP_EXT) }, 57 { ALIAS_EFI, ALIAS_INT2TYPE(DOSPTYP_EFI) }, 58 { ALIAS_FAT16B, ALIAS_INT2TYPE(DOSPTYP_FAT16B) }, 59 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) }, 60 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) }, 61 { ALIAS_NTFS, ALIAS_INT2TYPE(DOSPTYP_NTFS) }, 62 { ALIAS_PPCBOOT, ALIAS_INT2TYPE(DOSPTYP_PPCBOOT) }, 63 { ALIAS_NONE, 0 } /* Keep last! */ 64 }; 65 66 static lba_t 67 mbr_metadata(u_int where, lba_t blk) 68 { 69 70 blk += (where == SCHEME_META_IMG_START) ? 1 : 0; 71 return (round_track(blk)); 72 } 73 74 static void 75 mbr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba) 76 { 77 u_int cyl, hd, sec; 78 79 mkimg_chs(lba, 1023, &cyl, &hd, &sec); 80 *cylp = cyl; 81 *hdp = hd; 82 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 83 } 84 85 static int 86 mbr_write(lba_t imgsz __unused, void *bootcode) 87 { 88 u_char *mbr; 89 struct dos_partition *dpbase, *dp; 90 struct part *part; 91 lba_t size; 92 int error; 93 94 mbr = malloc(secsz); 95 if (mbr == NULL) 96 return (ENOMEM); 97 if (bootcode != NULL) { 98 memcpy(mbr, bootcode, DOSPARTOFF); 99 memset(mbr + DOSPARTOFF, 0, secsz - DOSPARTOFF); 100 } else 101 memset(mbr, 0, secsz); 102 le16enc(mbr + DOSMAGICOFFSET, DOSMAGIC); 103 dpbase = (void *)(mbr + DOSPARTOFF); 104 STAILQ_FOREACH(part, &partlist, link) { 105 size = round_track(part->size); 106 dp = dpbase + part->index; 107 dp->dp_flag = (part->index == 0 && bootcode != NULL) ? 0x80 : 0; 108 mbr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, 109 part->block); 110 dp->dp_typ = ALIAS_TYPE2INT(part->type); 111 mbr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect, 112 part->block + size - 1); 113 le32enc(&dp->dp_start, part->block); 114 le32enc(&dp->dp_size, size); 115 } 116 error = image_write(0, mbr, 1); 117 free(mbr); 118 return (error); 119 } 120 121 static struct mkimg_scheme mbr_scheme = { 122 .name = "mbr", 123 .description = "Master Boot Record", 124 .aliases = mbr_aliases, 125 .metadata = mbr_metadata, 126 .write = mbr_write, 127 .bootcode = 512, 128 .nparts = NDOSPART, 129 .maxsecsz = 4096 130 }; 131 132 SCHEME_DEFINE(mbr_scheme); 133