usr.sbin/installboot/arch/landisk.c

   1 /*      $NetBSD: landisk.c,v 1.6 2013/10/19 17:08:15 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 1.6 2013/10/19 17:08:15 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                 if (params->flags & IB_VERBOSE) {
 104                         printf(
 105                     "Ignoring MBR with invalid magic in sector 0 of `%s'\n",
 106                             params->filesystem);
 107                 }
 108                 memset(&mbr, 0, sizeof(mbr));
 109         }
 110
 111         /*
 112          * Allocate a buffer, with space to round up the input file
 113          * to the next block size boundary, and with space for the boot
 114          * block.
 115          */
 116         bootstrapsize = roundup(params->s1stat.st_size, 512);
 117
 118         bootstrapbuf = malloc(bootstrapsize);
 119         if (bootstrapbuf == NULL) {
 120                 warn("Allocating %zu bytes",  bootstrapsize);
 121                 goto done;
 122         }
 123         memset(bootstrapbuf, 0, bootstrapsize);
 124
 125         /*
 126          * Read the file into the buffer.
 127          */
 128         rv = pread(params->s1fd, bootstrapbuf, params->s1stat.st_size, 0);
 129         if (rv == -1) {
 130                 warn("Reading `%s'", params->stage1);
 131                 goto done;
 132         } else if (rv != params->s1stat.st_size) {
 133                 warnx("Reading `%s': short read", params->stage1);
 134                 goto done;
 135         }
 136
 137         magic = *(uint32_t *)(bootstrapbuf + 512 * 2 + 4);
 138         if (magic != htole32(LANDISK_BOOT_MAGIC_1)) {
 139                 warnx("Invalid magic in stage1 boostrap %x != %x",
 140                         magic, htole32(LANDISK_BOOT_MAGIC_1));
 141                 goto done;
 142         }
 143
 144         /*
 145          * Determine size of BIOS Parameter Block (BPB) to copy from
 146          * original MBR to the temporary buffer by examining the first
 147          * few instruction in the new bootblock.  Supported values:
 148          *      2b a0 11        jmp ENDOF(mbr_bpbFAT32)+1, nop
 149          *      (anything else) ; don't preserve
 150          */
 151 #if 0
 152         int bpbsize;
 153         if (bootstrapbuf[1] == 0xa0 && bootstrapbuf[2] == 0x11 &&
 154             (bootstrapbuf[0] == 0x2b /*|| bootstrapbuf[0] == 0x1d*/)) {
 155                  bpbsize = bootstrapbuf[0] + 2 - MBR_BPB_OFFSET;
 156         }
 157 #endif
 158
 159         /*
 160          * Ensure bootxx hasn't got any code or data (i.e, non-zero bytes) in
 161          * the partition table.
 162          */
 163         for (i = 0; i < (int)sizeof(mbr.mbr_parts); i++) {
 164                 if (*(uint8_t *)(bootstrapbuf + MBR_PART_OFFSET + i) != 0) {
 165                         warnx(
 166                     "Partition table has non-zero byte at offset %d in `%s'",
 167                             MBR_PART_OFFSET + i, params->stage1);
 168                         goto done;
 169                 }
 170         }
 171
 172 #if 0
 173         /*
 174          * Copy the BPB and the partition table from the original MBR to the
 175          * temporary buffer so that they're written back to the fs.
 176          */
 177         if (bpbsize != 0) {
 178                 if (params->flags & IB_VERBOSE)
 179                         printf("Preserving %d (%#x) bytes of the BPB\n",
 180                             bpbsize, bpbsize);
 181                 (void)memcpy(bootstrapbuf + MBR_BPB_OFFSET, &mbr.mbr_bpb,
 182                     bpbsize);
 183         }
 184 #endif
 185         memcpy(bootstrapbuf + MBR_PART_OFFSET, &mbr.mbr_parts,
 186             sizeof(mbr.mbr_parts));
 187
 188         /*
 189          * Fill in any user-specified options into the
 190          *      struct landisk_boot_params
 191          * that's 8 bytes in from the start of the third sector.
 192          * See sys/arch/landisk/stand/bootxx/bootxx.S for more information.
 193          */
 194         bpp = (void *)(bootstrapbuf + 512 * 2 + 8);
 195         bplen = le32toh(bpp->bp_length);
 196         if (bplen > sizeof bp)
 197                 /* Ignore pad space in bootxx */
 198                 bplen = sizeof bp;
 199         /* Take (and update) local copy so we handle size mismatches */
 200         memset(&bp, 0, sizeof bp);
 201         memcpy(&bp, bpp, bplen);
 202         if (params->flags & IB_TIMEOUT)
 203                 bp.bp_timeout = htole32(params->timeout);
 204         /* Check we aren't trying to set anything we can't save */
 205         if (bplen < sizeof bp && memcmp((char *)&bp + bplen,
 206                                         (char *)&bp + bplen + 1,
 207                                         sizeof bp - bplen - 1) != 0) {
 208                 warnx("Patch area in stage1 bootstrap is too small");
 209                 goto done;
 210         }
 211         memcpy(bpp, &bp, bplen);
 212
 213         if (params->flags & IB_NOWRITE) {
 214                 retval = 1;
 215                 goto done;
 216         }
 217
 218         /*
 219          * Write MBR code to sector zero.
 220          */
 221         rv = pwrite(params->fsfd, bootstrapbuf, 512, 0);
 222         if (rv == -1) {
 223                 warn("Writing `%s'", params->filesystem);
 224                 goto done;
 225         } else if (rv != 512) {
 226                 warnx("Writing `%s': short write", params->filesystem);
 227                 goto done;
 228         }
 229
 230         /*
 231          * Skip disklabel in sector 1 and write bootxx to sectors 2..N.
 232          */
 233         rv = pwrite(params->fsfd, bootstrapbuf + 512 * 2,
 234                     bootstrapsize - 512 * 2, 512 * 2);
 235         if (rv == -1) {
 236                 warn("Writing `%s'", params->filesystem);
 237                 goto done;
 238         } else if ((size_t)rv != bootstrapsize - 512 * 2) {
 239                 warnx("Writing `%s': short write", params->filesystem);
 240                 goto done;
 241         }
 242
 243         retval = 1;
 244
 245  done:
 246         if (bootstrapbuf)
 247                 free(bootstrapbuf);
 248         return retval;
 249 }