1/* $NetBSD: landisk.c,v 1.9 2024/05/11 06:50:23 andvar Exp $ */ 2 3/*- 4 * Copyright (c) 2003 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by David Laight. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#if HAVE_NBTOOL_CONFIG_H 33#include "nbtool_config.h" 34#endif 35 36#include <sys/cdefs.h> 37#if !defined(__lint) 38__RCSID("$NetBSD: landisk.c,v 1.9 2024/05/11 06:50:23 andvar Exp $"); 39#endif /* !__lint */ 40 41#include <sys/param.h> 42 43#include <assert.h> 44#include <err.h> 45#include <md5.h> 46#include <stddef.h> 47#include <stdio.h> 48#include <stdlib.h> 49#include <string.h> 50#include <unistd.h> 51 52#include "installboot.h" 53 54static int landisk_setboot(ib_params *); 55 56struct ib_mach ib_mach_landisk = { 57 .name = "landisk", 58 .setboot = landisk_setboot, 59 .clearboot = no_clearboot, 60 .editboot = no_editboot, 61 .valid_flags = IB_TIMEOUT, 62}; 63 64static int 65landisk_setboot(ib_params *params) 66{ 67 struct mbr_sector mbr; 68 struct landisk_boot_params bp, *bpp; 69 uint8_t *bootstrapbuf; 70 ssize_t rv; 71 uint32_t magic; 72 size_t bootstrapsize; 73 int retval, i; 74 uint32_t bplen; 75 76 assert(params != NULL); 77 assert(params->fsfd != -1); 78 assert(params->filesystem != NULL); 79 assert(params->s1fd != -1); 80 assert(params->stage1 != NULL); 81 82 retval = 0; 83 bootstrapbuf = NULL; 84 85 /* 86 * There is only 8k of space in a FFSv1 partition (and ustarfs) 87 * so ensure we don't splat over anything important. 88 */ 89 if (params->s1stat.st_size > 8192) { 90 warnx("stage1 bootstrap `%s' is larger than 8192 bytes", 91 params->stage1); 92 goto done; 93 } 94 95 /* 96 * Read in the existing MBR. 97 */ 98 rv = pread(params->fsfd, &mbr, sizeof(mbr), MBR_BBSECTOR); 99 if (rv == -1) { 100 warn("Reading `%s'", params->filesystem); 101 goto done; 102 } else if (rv != sizeof(mbr)) { 103 warnx("Reading `%s': short read", params->filesystem); 104 goto done; 105 } 106 if (mbr.mbr_magic != le16toh(MBR_MAGIC)) { 107 const char *p = (const char *)&mbr; 108 const char *e = p + sizeof(mbr); 109 while (p < e && !*p) 110 p++; 111 if (p != e) { 112 if (params->flags & IB_VERBOSE) { 113 printf( 114 "Ignoring MBR with invalid magic in sector 0 of `%s'\n", 115 params->filesystem); 116 } 117 memset(&mbr, 0, sizeof(mbr)); 118 } 119 } 120 121 /* 122 * Allocate a buffer, with space to round up the input file 123 * to the next block size boundary, and with space for the boot 124 * block. 125 */ 126 bootstrapsize = roundup(params->s1stat.st_size, 512); 127 128 bootstrapbuf = malloc(bootstrapsize); 129 if (bootstrapbuf == NULL) { 130 warn("Allocating %zu bytes", bootstrapsize); 131 goto done; 132 } 133 memset(bootstrapbuf, 0, bootstrapsize); 134 135 /* 136 * Read the file into the buffer. 137 */ 138 rv = pread(params->s1fd, bootstrapbuf, params->s1stat.st_size, 0); 139 if (rv == -1) { 140 warn("Reading `%s'", params->stage1); 141 goto done; 142 } else if (rv != params->s1stat.st_size) { 143 warnx("Reading `%s': short read", params->stage1); 144 goto done; 145 } 146 147 magic = *(uint32_t *)(bootstrapbuf + 512 * 2 + 4); 148 if (magic != htole32(LANDISK_BOOT_MAGIC_1)) { 149 warnx("Invalid magic in stage1 bootstrap %x != %x", 150 magic, htole32(LANDISK_BOOT_MAGIC_1)); 151 goto done; 152 } 153 154 /* 155 * Determine size of BIOS Parameter Block (BPB) to copy from 156 * original MBR to the temporary buffer by examining the first 157 * few instruction in the new bootblock. Supported values: 158 * 2b a0 11 jmp ENDOF(mbr_bpbFAT32)+1, nop 159 * (anything else) ; don't preserve 160 */ 161#if 0 162 int bpbsize; 163 if (bootstrapbuf[1] == 0xa0 && bootstrapbuf[2] == 0x11 && 164 (bootstrapbuf[0] == 0x2b /*|| bootstrapbuf[0] == 0x1d*/)) { 165 bpbsize = bootstrapbuf[0] + 2 - MBR_BPB_OFFSET; 166 } 167#endif 168 169 /* 170 * Ensure bootxx hasn't got any code or data (i.e, non-zero bytes) in 171 * the partition table. 172 */ 173 for (i = 0; i < (int)sizeof(mbr.mbr_parts); i++) { 174 if (*(uint8_t *)(bootstrapbuf + MBR_PART_OFFSET + i) != 0) { 175 warnx( 176 "Partition table has non-zero byte at offset %d in `%s'", 177 MBR_PART_OFFSET + i, params->stage1); 178 goto done; 179 } 180 } 181 182#if 0 183 /* 184 * Copy the BPB and the partition table from the original MBR to the 185 * temporary buffer so that they're written back to the fs. 186 */ 187 if (bpbsize != 0) { 188 if (params->flags & IB_VERBOSE) 189 printf("Preserving %d (%#x) bytes of the BPB\n", 190 bpbsize, bpbsize); 191 (void)memcpy(bootstrapbuf + MBR_BPB_OFFSET, &mbr.mbr_bpb, 192 bpbsize); 193 } 194#endif 195 memcpy(bootstrapbuf + MBR_PART_OFFSET, &mbr.mbr_parts, 196 sizeof(mbr.mbr_parts)); 197 198 /* 199 * Fill in any user-specified options into the 200 * struct landisk_boot_params 201 * that's 8 bytes in from the start of the third sector. 202 * See sys/arch/landisk/stand/bootxx/bootxx.S for more information. 203 */ 204 bpp = (void *)(bootstrapbuf + 512 * 2 + 8); 205 bplen = le32toh(bpp->bp_length); 206 if (bplen > sizeof bp) 207 /* Ignore pad space in bootxx */ 208 bplen = sizeof bp; 209 /* Take (and update) local copy so we handle size mismatches */ 210 memset(&bp, 0, sizeof bp); 211 memcpy(&bp, bpp, bplen); 212 if (params->flags & IB_TIMEOUT) 213 bp.bp_timeout = htole32(params->timeout); 214 /* Check we aren't trying to set anything we can't save */ 215 if (bplen < sizeof bp && memcmp((char *)&bp + bplen, 216 (char *)&bp + bplen + 1, 217 sizeof bp - bplen - 1) != 0) { 218 warnx("Patch area in stage1 bootstrap is too small"); 219 goto done; 220 } 221 memcpy(bpp, &bp, bplen); 222 223 if (params->flags & IB_NOWRITE) { 224 retval = 1; 225 goto done; 226 } 227 228 /* 229 * Write MBR code to sector zero. 230 */ 231 rv = pwrite(params->fsfd, bootstrapbuf, 512, 0); 232 if (rv == -1) { 233 warn("Writing `%s'", params->filesystem); 234 goto done; 235 } else if (rv != 512) { 236 warnx("Writing `%s': short write", params->filesystem); 237 goto done; 238 } 239 240 /* 241 * Skip disklabel in sector 1 and write bootxx to sectors 2..N. 242 */ 243 rv = pwrite(params->fsfd, bootstrapbuf + 512 * 2, 244 bootstrapsize - 512 * 2, 512 * 2); 245 if (rv == -1) { 246 warn("Writing `%s'", params->filesystem); 247 goto done; 248 } else if ((size_t)rv != bootstrapsize - 512 * 2) { 249 warnx("Writing `%s': short write", params->filesystem); 250 goto done; 251 } 252 253 retval = 1; 254 255 done: 256 if (bootstrapbuf) 257 free(bootstrapbuf); 258 return retval; 259} 260