NetBSD/sbin/gpt/biosboot.c

326 lines
7.6 KiB
C

/* $NetBSD: biosboot.c,v 1.30 2017/09/07 10:23:33 christos Exp $ */
/*
* Copyright (c) 2009 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to the NetBSD Foundation
* by Mike M. Volokhov. Development of this software was supported by the
* Google Summer of Code program.
* The GSoC project was mentored by Allen Briggs and Joerg Sonnenberger.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif
#include <sys/cdefs.h>
#ifdef __RCSID
__RCSID("$NetBSD: biosboot.c,v 1.30 2017/09/07 10:23:33 christos Exp $");
#endif
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/bootblock.h>
#if defined(DIOCGWEDGEINFO) && !defined(HAVE_NBTOOL_CONFIG_H)
#define USE_WEDGES
#endif
#ifdef USE_WEDGES
#include <sys/disk.h>
#endif
#include <err.h>
#include <fcntl.h>
#include <paths.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "map.h"
#include "gpt.h"
#include "gpt_private.h"
#define DEFAULT_BOOTDIR "/usr/mdec"
#define DEFAULT_BOOTCODE "gptmbr.bin"
static int cmd_biosboot(gpt_t, int, char *[]);
static const char *biosboothelp[] = {
"[-A] [-c bootcode] [-i index] [-L label]",
#if notyet
"[-a alignment] [-b blocknr] [-i index] [-l label]",
"[-s size] [-t type]",
#endif
};
struct gpt_cmd c_biosboot = {
"biosboot",
cmd_biosboot,
biosboothelp, __arraycount(biosboothelp),
0,
};
#define usage() gpt_usage(NULL, &c_biosboot)
static struct mbr*
read_boot(gpt_t gpt, const char *bootpath)
{
int bfd, ret = -1;
struct mbr *buf;
struct stat st;
char *bp;
buf = NULL;
bfd = -1;
if (bootpath == NULL)
bp = strdup(DEFAULT_BOOTDIR "/" DEFAULT_BOOTCODE);
else if (*bootpath == '/')
bp = strdup(bootpath);
else {
if (asprintf(&bp, "%s/%s", DEFAULT_BOOTDIR, bootpath) < 0)
bp = NULL;
}
if (bp == NULL) {
gpt_warn(gpt, "Can't allocate memory for bootpath");
goto fail;
}
if ((buf = malloc((size_t)gpt->secsz)) == NULL) {
gpt_warn(gpt, "Can't allocate memory for sector");
goto fail;
}
if ((bfd = open(bp, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
gpt_warn(gpt, "Can't open `%s'", bp);
goto fail;
}
if (st.st_size != MBR_DSN_OFFSET) {
gpt_warnx(gpt, "The bootcode in `%s' does not match the"
" expected size %u", bp, MBR_DSN_OFFSET);
goto fail;
}
if (read(bfd, buf, (size_t)st.st_size) != (ssize_t)st.st_size) {
gpt_warn(gpt, "Error reading from `%s'", bp);
goto fail;
}
ret = 0;
fail:
if (bfd != -1)
close(bfd);
if (ret == -1) {
free(buf);
buf = NULL;
}
free(bp);
return buf;
}
static int
set_bootable(gpt_t gpt, map_t map, map_t tbl, unsigned int i)
{
unsigned int j;
struct gpt_hdr *hdr = map->map_data;
struct gpt_ent *ent;
unsigned int ne = le32toh(hdr->hdr_entries);
for (j = 0; j < ne; j++) {
ent = gpt_ent(map, tbl, j);
ent->ent_attr &= ~GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
}
ent = gpt_ent(map, tbl, i);
ent->ent_attr |= GPT_ENT_ATTR_LEGACY_BIOS_BOOTABLE;
return gpt_write_crc(gpt, map, tbl);
}
static int
biosboot(gpt_t gpt, daddr_t start, uint64_t size, u_int entry, uint8_t *label,
const char *bootpath, int active)
{
map_t mbrmap, m;
struct mbr *mbr, *bootcode;
unsigned int i;
struct gpt_ent *ent;
uint8_t utfbuf[__arraycount(ent->ent_name) * 3 + 1];
/*
* Parse and validate partition maps
*/
if (gpt_hdr(gpt) == NULL)
return -1;
mbrmap = map_find(gpt, MAP_TYPE_PMBR);
if (mbrmap == NULL || mbrmap->map_start != 0) {
gpt_warnx(gpt, "No valid Protective MBR found");
return -1;
}
mbr = mbrmap->map_data;
/*
* Update the boot code
*/
if ((bootcode = read_boot(gpt, bootpath)) == NULL) {
gpt_warnx(gpt, "Error reading bootcode");
return -1;
}
(void)memcpy(&mbr->mbr_code, &bootcode->mbr_code,
sizeof(mbr->mbr_code));
free(bootcode);
for (i = 0; i < __arraycount(mbr->mbr_part); i++)
if (mbr->mbr_part[i].part_typ == MBR_PTYPE_PMBR)
mbr->mbr_part[i].part_flag = active ? 0x80 : 0;
/*
* Walk through the GPT and see where we can boot from
*/
for (m = map_first(gpt); m != NULL; m = m->map_next) {
if (m->map_type != MAP_TYPE_GPT_PART || m->map_index < 1)
continue;
ent = m->map_data;
/* first, prefer user selection */
if (entry > 0 && m->map_index == entry)
break;
if (label != NULL) {
utf16_to_utf8(ent->ent_name,
__arraycount(ent->ent_name), utfbuf,
__arraycount(utfbuf));
if (strcmp((char *)label, (char *)utfbuf) == 0)
break;
}
/* next, partition as could be specified by wedge */
if (entry < 1 && label == NULL && size > 0 &&
m->map_start == start && m->map_size == (off_t)size)
break;
}
if (m == NULL) {
gpt_warnx(gpt, "No bootable partition");
return -1;
}
i = m->map_index - 1;
if (set_bootable(gpt, gpt->gpt, gpt->tbl, i) == -1)
return -1;
if (set_bootable(gpt, gpt->tpg, gpt->lbt, i) == -1)
return -1;
if (gpt_write(gpt, mbrmap) == -1) {
gpt_warnx(gpt, "Cannot update Protective MBR");
return -1;
}
gpt_msg(gpt, "Partition %d marked as bootable", i + 1);
return 0;
}
static int
cmd_biosboot(gpt_t gpt, int argc, char *argv[])
{
#ifdef USE_WEDGES
struct dkwedge_info dkw;
#endif
int ch;
gpt_t ngpt = gpt;
daddr_t start = 0;
uint64_t size = 0;
int active = 0;
unsigned int entry = 0;
uint8_t *label = NULL;
char *bootpath = NULL;
while ((ch = getopt(argc, argv, "Ac:i:L:")) != -1) {
switch(ch) {
case 'A':
active = 1;
break;
case 'c':
if (gpt_name_get(gpt, &bootpath) == -1)
goto usage;
break;
case 'i':
if (gpt_uint_get(gpt, &entry) == -1)
goto usage;
break;
case 'L':
if (gpt_name_get(gpt, &label) == -1)
goto usage;
break;
default:
goto usage;
}
}
if (argc != optind)
return usage();
#ifdef USE_WEDGES
if ((gpt->sb.st_mode & S_IFMT) != S_IFREG &&
ioctl(gpt->fd, DIOCGWEDGEINFO, &dkw) != -1) {
if (entry > 0)
/* wedges and indexes are mutually exclusive */
goto usage;
start = dkw.dkw_offset;
size = dkw.dkw_size;
ngpt = gpt_open(dkw.dkw_parent, gpt->flags, gpt->verbose,
gpt->mediasz, gpt->secsz, gpt->timestamp);
if (ngpt == NULL)
goto cleanup;
}
#endif
if (biosboot(ngpt, start, size, entry, label, bootpath, active) == -1)
goto cleanup;
if (ngpt != gpt)
gpt_close(ngpt);
return 0;
usage:
usage();
cleanup:
if (ngpt != gpt)
gpt_close(ngpt);
free(bootpath);
free(label);
return -1;
}