1 /* $NetBSD: landisk.c,v 1.7 2017/07/17 18:43:45 christos 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 1.7 2017/07/17 18:43:45 christos 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 54 static int landisk_setboot(ib_params *); 55 56 struct ib_mach ib_mach_landisk = 57 { "landisk", landisk_setboot, no_clearboot, no_editboot, 58 IB_TIMEOUT }; 59 60 static int 61 landisk_setboot(ib_params *params) 62 { 63 struct mbr_sector mbr; 64 struct landisk_boot_params bp, *bpp; 65 uint8_t *bootstrapbuf; 66 ssize_t rv; 67 uint32_t magic; 68 size_t bootstrapsize; 69 int retval, i; 70 uint32_t bplen; 71 72 assert(params != NULL); 73 assert(params->fsfd != -1); 74 assert(params->filesystem != NULL); 75 assert(params->s1fd != -1); 76 assert(params->stage1 != NULL); 77 78 retval = 0; 79 bootstrapbuf = NULL; 80 81 /* 82 * There is only 8k of space in a FFSv1 partition (and ustarfs) 83 * so ensure we don't splat over anything important. 84 */ 85 if (params->s1stat.st_size > 8192) { 86 warnx("stage1 bootstrap `%s' is larger than 8192 bytes", 87 params->stage1); 88 goto done; 89 } 90 91 /* 92 * Read in the existing MBR. 93 */ 94 rv = pread(params->fsfd, &mbr, sizeof(mbr), MBR_BBSECTOR); 95 if (rv == -1) { 96 warn("Reading `%s'", params->filesystem); 97 goto done; 98 } else if (rv != sizeof(mbr)) { 99 warnx("Reading `%s': short read", params->filesystem); 100 goto done; 101 } 102 if (mbr.mbr_magic != le16toh(MBR_MAGIC)) { 103 const char *p = (const char *)&mbr; 104 const char *e = p + sizeof(mbr); 105 while (p < e && !*p) 106 p++; 107 if (p != e) { 108 if (params->flags & IB_VERBOSE) { 109 printf( 110 "Ignoring MBR with invalid magic in sector 0 of `%s'\n", 111 params->filesystem); 112 } 113 memset(&mbr, 0, sizeof(mbr)); 114 } 115 } 116 117 /* 118 * Allocate a buffer, with space to round up the input file 119 * to the next block size boundary, and with space for the boot 120 * block. 121 */ 122 bootstrapsize = roundup(params->s1stat.st_size, 512); 123 124 bootstrapbuf = malloc(bootstrapsize); 125 if (bootstrapbuf == NULL) { 126 warn("Allocating %zu bytes", bootstrapsize); 127 goto done; 128 } 129 memset(bootstrapbuf, 0, bootstrapsize); 130 131 /* 132 * Read the file into the buffer. 133 */ 134 rv = pread(params->s1fd, bootstrapbuf, params->s1stat.st_size, 0); 135 if (rv == -1) { 136 warn("Reading `%s'", params->stage1); 137 goto done; 138 } else if (rv != params->s1stat.st_size) { 139 warnx("Reading `%s': short read", params->stage1); 140 goto done; 141 } 142 143 magic = *(uint32_t *)(bootstrapbuf + 512 * 2 + 4); 144 if (magic != htole32(LANDISK_BOOT_MAGIC_1)) { 145 warnx("Invalid magic in stage1 boostrap %x != %x", 146 magic, htole32(LANDISK_BOOT_MAGIC_1)); 147 goto done; 148 } 149 150 /* 151 * Determine size of BIOS Parameter Block (BPB) to copy from 152 * original MBR to the temporary buffer by examining the first 153 * few instruction in the new bootblock. Supported values: 154 * 2b a0 11 jmp ENDOF(mbr_bpbFAT32)+1, nop 155 * (anything else) ; don't preserve 156 */ 157 #if 0 158 int bpbsize; 159 if (bootstrapbuf[1] == 0xa0 && bootstrapbuf[2] == 0x11 && 160 (bootstrapbuf[0] == 0x2b /*|| bootstrapbuf[0] == 0x1d*/)) { 161 bpbsize = bootstrapbuf[0] + 2 - MBR_BPB_OFFSET; 162 } 163 #endif 164 165 /* 166 * Ensure bootxx hasn't got any code or data (i.e, non-zero bytes) in 167 * the partition table. 168 */ 169 for (i = 0; i < (int)sizeof(mbr.mbr_parts); i++) { 170 if (*(uint8_t *)(bootstrapbuf + MBR_PART_OFFSET + i) != 0) { 171 warnx( 172 "Partition table has non-zero byte at offset %d in `%s'", 173 MBR_PART_OFFSET + i, params->stage1); 174 goto done; 175 } 176 } 177 178 #if 0 179 /* 180 * Copy the BPB and the partition table from the original MBR to the 181 * temporary buffer so that they're written back to the fs. 182 */ 183 if (bpbsize != 0) { 184 if (params->flags & IB_VERBOSE) 185 printf("Preserving %d (%#x) bytes of the BPB\n", 186 bpbsize, bpbsize); 187 (void)memcpy(bootstrapbuf + MBR_BPB_OFFSET, &mbr.mbr_bpb, 188 bpbsize); 189 } 190 #endif 191 memcpy(bootstrapbuf + MBR_PART_OFFSET, &mbr.mbr_parts, 192 sizeof(mbr.mbr_parts)); 193 194 /* 195 * Fill in any user-specified options into the 196 * struct landisk_boot_params 197 * that's 8 bytes in from the start of the third sector. 198 * See sys/arch/landisk/stand/bootxx/bootxx.S for more information. 199 */ 200 bpp = (void *)(bootstrapbuf + 512 * 2 + 8); 201 bplen = le32toh(bpp->bp_length); 202 if (bplen > sizeof bp) 203 /* Ignore pad space in bootxx */ 204 bplen = sizeof bp; 205 /* Take (and update) local copy so we handle size mismatches */ 206 memset(&bp, 0, sizeof bp); 207 memcpy(&bp, bpp, bplen); 208 if (params->flags & IB_TIMEOUT) 209 bp.bp_timeout = htole32(params->timeout); 210 /* Check we aren't trying to set anything we can't save */ 211 if (bplen < sizeof bp && memcmp((char *)&bp + bplen, 212 (char *)&bp + bplen + 1, 213 sizeof bp - bplen - 1) != 0) { 214 warnx("Patch area in stage1 bootstrap is too small"); 215 goto done; 216 } 217 memcpy(bpp, &bp, bplen); 218 219 if (params->flags & IB_NOWRITE) { 220 retval = 1; 221 goto done; 222 } 223 224 /* 225 * Write MBR code to sector zero. 226 */ 227 rv = pwrite(params->fsfd, bootstrapbuf, 512, 0); 228 if (rv == -1) { 229 warn("Writing `%s'", params->filesystem); 230 goto done; 231 } else if (rv != 512) { 232 warnx("Writing `%s': short write", params->filesystem); 233 goto done; 234 } 235 236 /* 237 * Skip disklabel in sector 1 and write bootxx to sectors 2..N. 238 */ 239 rv = pwrite(params->fsfd, bootstrapbuf + 512 * 2, 240 bootstrapsize - 512 * 2, 512 * 2); 241 if (rv == -1) { 242 warn("Writing `%s'", params->filesystem); 243 goto done; 244 } else if ((size_t)rv != bootstrapsize - 512 * 2) { 245 warnx("Writing `%s': short write", params->filesystem); 246 goto done; 247 } 248 249 retval = 1; 250 251 done: 252 if (bootstrapbuf) 253 free(bootstrapbuf); 254 return retval; 255 } 256