/* $NetBSD: boot1.c,v 1.22 2023/06/29 14:18:58 manu Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by David Laight.
*
* 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.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: boot1.c,v 1.22 2023/06/29 14:18:58 manu Exp $");
#include <lib/libsa/stand.h>
#include <lib/libkern/libkern.h>
#include <biosdisk_ll.h>
#include <sys/param.h>
#include <sys/uuid.h>
#include <sys/bootblock.h>
#include <sys/disklabel.h>
#include <sys/disklabel_gpt.h>
#include <dev/raidframe/raidframevar.h> /* For RF_PROTECTED_SECTORS */
#define XSTR(x) #x
#define STR(x) XSTR(x)
static daddr_t bios_sector;
static struct biosdisk_ll d;
const char *boot1(uint32_t, uint64_t *);
#ifndef NO_GPT
static daddr_t gpt_lookup(daddr_t);
#endif
extern void putstr(const char *);
extern struct disklabel ptn_disklabel;
static int
ob(void)
{
return open("boot", 0);
}
const char *
boot1(uint32_t biosdev, uint64_t *sector)
{
struct stat sb;
int fd;
bios_sector = *sector;
d.dev = biosdev;
putstr("\r\nNetBSD/x86 " STR(FS) " Primary Bootstrap\r\n");
if (set_geometry(&d, NULL))
return "set_geometry\r\n";
/*
* We default to the filesystem at the start of the
* MBR partition
*/
fd = ob();
if (fd != -1)
goto done;
/*
* Maybe the filesystem is enclosed in a raid set.
* add in size of raidframe header and try again.
* (Maybe this should only be done if the filesystem
* magic number is absent.)
*/
bios_sector += RF_PROTECTED_SECTORS;
fd = ob();
if (fd != -1)
goto done;
#ifndef NO_GPT
/*
* Test for a GPT inside the RAID
*/
bios_sector += gpt_lookup(bios_sector);
fd = ob();
if (fd != -1)
goto done;
#endif
/*
* Nothing at the start of the MBR partition, fallback on
* partition 'a' from the disklabel in this MBR partition.
*/
if (ptn_disklabel.d_magic != DISKMAGIC ||
ptn_disklabel.d_magic2 != DISKMAGIC ||
ptn_disklabel.d_partitions[0].p_fstype == FS_UNUSED)
goto done;
bios_sector = ptn_disklabel.d_partitions[0].p_offset;
*sector = bios_sector;
if (ptn_disklabel.d_partitions[0].p_fstype == FS_RAID)
bios_sector += RF_PROTECTED_SECTORS;
fd = ob();
done:
if (fd == -1 || fstat(fd, &sb) == -1)
return "Can't open /boot\r\n";
biosdev = (uint32_t)sb.st_size;
#if 0
if (biosdev > SECONDARY_MAX_LOAD)
return "/boot too large\r\n";
#endif
if (read(fd, (void *)SECONDARY_LOAD_ADDRESS, biosdev) != biosdev)
return "/boot load failed\r\n";
if (*(uint32_t *)(SECONDARY_LOAD_ADDRESS + 4) != X86_BOOT_MAGIC_2)
return "Invalid /boot file format\r\n";
/* We need to jump to the secondary bootstrap in realmode */
return 0;
}
int
blkdevstrategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize)
{
if (flag != F_READ)
return EROFS;
if (size & (BIOSDISK_DEFAULT_SECSIZE - 1))
return EINVAL;
if (rsize)
*rsize = size;
if (size != 0 && readsects(&d, bios_sector + dblk,
size / BIOSDISK_DEFAULT_SECSIZE,
buf, 1) != 0)
return EIO;
return 0;
}
#ifndef NO_GPT
static int
is_unused(struct gpt_ent *ent)
{
const struct uuid unused = GPT_ENT_TYPE_UNUSED;
return (memcmp(ent->ent_type, &unused, sizeof(unused)) == 0);
}
static int
is_bootable(struct gpt_ent *ent)
{
/* GPT_ENT_TYPE_NETBSD_RAID omitted as we are already in a RAID */
const struct uuid bootable[] = {
GPT_ENT_TYPE_NETBSD_FFS,
GPT_ENT_TYPE_NETBSD_LFS,
GPT_ENT_TYPE_NETBSD_CCD,
GPT_ENT_TYPE_NETBSD_CGD,
};
int i;
for (i = 0; i < sizeof(bootable) / sizeof(*bootable); i++) {
if (memcmp(ent->ent_type, &bootable[i],
sizeof(struct uuid)) == 0)
return 1;
}
return 0;
}
static daddr_t
gpt_lookup(daddr_t sector)
{
char buf[BIOSDISK_DEFAULT_SECSIZE];
struct mbr_sector *pmbr;
const char gpt_hdr_sig[] = GPT_HDR_SIG;
struct gpt_hdr *hdr;
struct gpt_ent *ent;
uint32_t nents;
uint32_t entsz;
uint32_t entries_per_sector;
uint32_t sectors_per_entry;
uint64_t firstpart_lba = 0;
uint64_t bootable_lba = 0;
uint64_t bootme_lba = 0;
int i, j;
/*
* Look for a PMBR
*/
if (readsects(&d, sector, 1, buf, 1) != 0)
return 0;
pmbr = (struct mbr_sector *)buf;
if (pmbr->mbr_magic != htole16(MBR_MAGIC))
return 0;
if (pmbr->mbr_parts[0].mbrp_type != MBR_PTYPE_PMBR)
return 0;
sector++; /* skip PMBR */
/*
* Look for a GPT header
* Space is scarce, we do not check CRC.
*/
if (readsects(&d, sector, 1, buf, 1) != 0)
return 0;
hdr = (struct gpt_hdr *)buf;
if (memcmp(gpt_hdr_sig, hdr->hdr_sig, sizeof(hdr->hdr_sig)) != 0)
return 0;
if (hdr->hdr_revision != htole32(GPT_HDR_REVISION))
return 0;
if (le32toh(hdr->hdr_size) > BIOSDISK_DEFAULT_SECSIZE)
return 0;
nents = le32toh(hdr->hdr_entries);
entsz = le32toh(hdr->hdr_entsz);
sector++; /* skip GPT header */
/*
* Read partition table
*
* According to UEFI specification section 5.3.2, entries
* are 128 * (2^n) bytes long. The most common scenario is
* 128 bytes (n = 0) where there are 4 entries per sector.
* If n > 2, then entries spans multiple sectors, but they
* remain sector-aligned.
*/
entries_per_sector = BIOSDISK_DEFAULT_SECSIZE / entsz;
if (entries_per_sector == 0)
entries_per_sector = 1;
sectors_per_entry = entsz / BIOSDISK_DEFAULT_SECSIZE;
if (sectors_per_entry == 0)
sectors_per_entry = 1;
for (i = 0; i < nents; i += entries_per_sector) {
if (readsects(&d, sector, 1, buf, 1) != 0)
return 0;
sector += sectors_per_entry;
for (j = 0; j < entries_per_sector; j++) {
ent = (struct gpt_ent *)&buf[j * entsz];
if (is_unused(ent))
continue;
/* First bootme wins, we can stop there */
if (ent->ent_attr & GPT_ENT_ATTR_BOOTME) {
bootme_lba = le64toh(ent->ent_lba_start);
goto out;
}
if (firstpart_lba == 0)
firstpart_lba = le64toh(ent->ent_lba_start);
if (is_bootable(ent) && bootable_lba == 0)
bootable_lba = le64toh(ent->ent_lba_start);
}
}
out:
if (bootme_lba)
return bootme_lba;
if (bootable_lba)
return bootable_lba;
if (firstpart_lba)
return firstpart_lba;
return 0;
}
#endif /* ! NO_GPT */