NetBSD/sys/arch/alpha/stand/installboot/installboot.c

460 lines
14 KiB
C

/* $NetBSD: installboot.c,v 1.23 2001/02/19 22:48:57 cgd Exp $ */
/*
* Copyright (c) 1999 Ross Harvey. All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Ross Harvey
* for the NetBSD Project.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/*
* Copyright (c) 1999 Christopher G. Demetriou. All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christopher G. Demetriou
* for the NetBSD Project.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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/param.h> /* XXX for roundup, howmany */
#include <sys/stat.h>
#include <include/disklabel.h> /* defeat <machine/disklabel.h>, force alpha */
#include <sys/disklabel.h>
#include <dev/sun/disklabel.h>
#include <assert.h>
#include <err.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
static void usage(void);
static void clr_bootstrap(const char *disk);
void check_sparc(const struct boot_block * const, const char *);
static u_int16_t compute_sparc(const u_int16_t *);
static void sun_bootstrap(struct boot_block * const);
static void set_bootstrap(const char *disk, const char *bootstrap);
int sunrewrite, sunflag, verbose, nowrite;
static void
usage()
{
fprintf(stderr, "usage:\n");
fprintf(stderr, "\t%s [-nsv] disk bootstrap\n", getprogname());
fprintf(stderr, "\t%s [-nsv] -c disk\n", getprogname());
exit(EXIT_FAILURE);
}
int
main(int argc, char **argv)
{
const char *disk, *bootstrap;
int c, clearflag;
clearflag = verbose = nowrite = 0;
while ((c = getopt(argc, argv, "cnsSv")) != -1) {
switch (c) {
case 'c':
/* Clear any existing boot block */
if (sunflag)
goto argdeath;
clearflag = 1;
break;
case 'n':
/* Do not actually write the boot file */
nowrite = 1;
break;
case 'S':
/* undocumented transition period fixup flag */
sunrewrite = 1;
/* fall thru */
case 's':
/*
* Sun checksum and magic number overlay
*/
if (clearflag)
goto argdeath;
sunflag = 1;
break;
case 'v':
/* Chat */
verbose = 1;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (sunrewrite) {
if(argc != 1)
usage();
} else if ((clearflag && argc != 1) || (!clearflag && argc != 2))
usage();
disk = argv[0];
bootstrap = argv[1]; /* NULL if argc == 1 */
if (verbose) {
fprintf(stderr, "disk: %s\n", disk);
fprintf(stderr, "bootstrap: %s\n",
bootstrap != NULL ? bootstrap : "to be cleared");
}
if (sizeof (struct boot_block) != BOOT_BLOCK_BLOCKSIZE)
errx(EXIT_FAILURE,
"boot_block structure badly sized (build error)");
if (clearflag)
clr_bootstrap(disk);
else
set_bootstrap(disk, bootstrap);
exit(EXIT_SUCCESS);
argdeath:
errx(EXIT_FAILURE, "incompatible options");
}
static void
clr_bootstrap(const char *disk)
{
struct boot_block bb;
u_int64_t cksum;
ssize_t rv;
int diskfd;
if ((diskfd = open(disk, nowrite ? O_RDONLY : O_RDWR)) == -1)
err(EXIT_FAILURE, "open %s", disk);
rv = pread(diskfd, &bb, sizeof bb, BOOT_BLOCK_OFFSET);
if (rv == -1)
err(EXIT_FAILURE, "read %s", disk);
else if (rv != sizeof bb)
errx(EXIT_FAILURE, "read %s: short read", disk);
CHECKSUM_BOOT_BLOCK(&bb, &cksum);
if (cksum != bb.bb_cksum) {
fprintf(stderr,
"old boot block checksum invalid (was %#llx,"
" calculated %#llx)\n",
(unsigned long long)bb.bb_cksum,
(unsigned long long)cksum);
fprintf(stderr, "boot block invalid\n");
goto done;
} else if (verbose) {
fprintf(stderr, "old boot block checksum: %#llx\n",
(unsigned long long)bb.bb_cksum);
fprintf(stderr, "old boot block start sector: %#llx\n",
(unsigned long long)bb.bb_secstart);
fprintf(stderr, "old boot block size: %#llx\n",
(unsigned long long)bb.bb_secsize);
}
bb.bb_secstart = bb.bb_secsize = bb.bb_flags = 0;
CHECKSUM_BOOT_BLOCK(&bb, &bb.bb_cksum);
fprintf(stderr, "new boot block checksum: %#llx\n",
(unsigned long long)bb.bb_cksum);
fprintf(stderr, "new boot block start sector: %#llx\n",
(unsigned long long)bb.bb_secstart);
fprintf(stderr, "new boot block size: %#llx\n",
(unsigned long long)bb.bb_secsize);
if (nowrite) {
if (verbose)
fprintf(stderr, "not writing\n");
goto done;
}
if (verbose)
fprintf(stderr, "writing\n");
rv = pwrite(diskfd, &bb, sizeof bb, BOOT_BLOCK_OFFSET);
if (rv == -1)
err(EXIT_FAILURE, "write %s", disk);
else if (rv != sizeof bb)
errx(EXIT_FAILURE, "write %s: short write", disk);
done:
(void)close(diskfd);
}
static void
set_bootstrap(const char *disk, const char *bootstrap)
{
struct stat bootstrapsb;
struct boot_block bb;
int bootstrapfd, diskfd;
char *bootstrapbuf;
size_t bootstrapsize;
ssize_t rv;
if (sunrewrite)
goto bbonly;
/* Open the input file and check it out */
if ((bootstrapfd = open(bootstrap, O_RDONLY)) == -1)
err(EXIT_FAILURE, "open %s", bootstrap);
if (fstat(bootstrapfd, &bootstrapsb) == -1)
err(EXIT_FAILURE, "fstat %s", bootstrap);
if (!S_ISREG(bootstrapsb.st_mode))
errx(EXIT_FAILURE, "%s must be a regular file", bootstrap);
/*
* Allocate a buffer, with space to round up the input file
* to the next block size boundary, and with space for the boot
* block.
*/
bootstrapsize = roundup(bootstrapsb.st_size, BOOT_BLOCK_BLOCKSIZE);
bootstrapbuf = malloc(bootstrapsize);
if (bootstrapbuf == NULL)
err(EXIT_FAILURE, "allocating buffer to hold bootstrap");
memset(bootstrapbuf, 0, bootstrapsize);
/* read the file into the buffer */
rv = read(bootstrapfd, bootstrapbuf, bootstrapsb.st_size);
if (rv == -1)
err(EXIT_FAILURE, "read %s", bootstrap);
else if (rv != bootstrapsb.st_size)
errx(EXIT_FAILURE, "read %s: short read", bootstrap);
(void)close(bootstrapfd);
bbonly:
if ((diskfd = open(disk, nowrite ? O_RDONLY : O_RDWR)) == -1)
err(EXIT_FAILURE, "open %s", disk);
rv = pread(diskfd, &bb, sizeof bb, BOOT_BLOCK_OFFSET);
if (rv == -1)
err(EXIT_FAILURE, "read %s", disk);
else if (rv != sizeof bb)
errx(EXIT_FAILURE, "read %s: short read", disk);
if (sunflag)
check_sparc(&bb, "initial");
/* fill in the updated boot block fields, and checksum boot block */
if (!sunrewrite) {
bb.bb_secsize = howmany(bootstrapsb.st_size,
BOOT_BLOCK_BLOCKSIZE);
bb.bb_secstart = 1;
bb.bb_flags = 0;
}
CHECKSUM_BOOT_BLOCK(&bb, &bb.bb_cksum);
if (verbose) {
fprintf(stderr, "bootstrap starting sector: %llu\n",
(unsigned long long)bb.bb_secstart);
fprintf(stderr, "bootstrap sector count: %llu\n",
(unsigned long long)bb.bb_secsize);
fprintf(stderr, "new boot block checksum: %#llx\n",
(unsigned long long)bb.bb_cksum);
}
if (sunflag)
sun_bootstrap(&bb);
if (nowrite) {
if (verbose)
fprintf(stderr, "not writing\n");
goto done;
}
if (verbose)
fprintf(stderr, "writing bootstrap\n");
if (!sunrewrite) {
rv = pwrite(diskfd, bootstrapbuf, bootstrapsize,
BOOT_BLOCK_OFFSET + BOOT_BLOCK_BLOCKSIZE);
if (rv == -1)
err(EXIT_FAILURE, "write %s", disk);
else if (rv != bootstrapsize)
errx(EXIT_FAILURE, "write %s: short write", disk);
if (verbose)
fprintf(stderr, "writing boot block\n");
}
rv = pwrite(diskfd, &bb, sizeof bb, BOOT_BLOCK_OFFSET);
if (rv == -1)
err(EXIT_FAILURE, "write %s", disk);
else if (rv != sizeof bb)
errx(EXIT_FAILURE, "write %s: short write", disk);
done:
(void)close(diskfd);
}
/*
* The Sun and alpha checksums overlay, and the Sun magic number also
* overlays the alpha checksum. If you think you are smart: stop here
* and do exercise one: figure out how to salt unimportant u_int16_t
* words in mid-sector so that the alpha and sparc checksums match,
* and so the Sun magic number is embedded in the alpha checksum.
*
* The last u_int64_t in the sector is the alpha arithmetic checksum.
* The last u_int16_t in the sector is the sun xor checksum.
* The penultimate u_int16_t in the sector is the sun magic number.
*
* A: 511 510 509 508 507 506 505 504
* S: 510 511 508 509 506 507 504 505
* 63 : : : 32:31 : : : 0
* | : : : \:| : : : |
* 7654321076543210765432107654321076543210765432107654321076543210
* |-- sparc --||-- sparc --|
* |-- checksum --||-- magic --|
* |----------------------- alpha checksum -----------------------|
* 1011111011011010
* b e d a
*/
static void
resum(struct boot_block * const bb, u_int16_t *bb16)
{
static u_int64_t lastsum;
if (bb16 != NULL)
memcpy(bb, bb16, sizeof *bb);
CHECKSUM_BOOT_BLOCK(bb, &bb->bb_cksum);
if (bb16 != NULL)
memcpy(bb16, bb, sizeof *bb);
if (verbose && lastsum != bb->bb_cksum)
printf("alpha checksum now %016llx\n", (long long)bb->bb_cksum);
lastsum = bb->bb_cksum;
}
static void
sun_bootstrap(struct boot_block * const bb)
{
# define BB_ADJUST_OFFSET 64
static char our_int16s[] = "\2\3\6\7\12";
u_int16_t i, j, chkdelta, sunsum, bb16[256];
/*
* Theory: the alpha checksum is adjusted so bits 47:32 add up
* to the Sun magic number. Then, another adjustment is computed
* so bits 63:48 add up to the Sun checksum, and applied in pieces
* so it changes the alpha checksum but not the Sun value.
*
* Note: using memcpy(3) instead of a union as a strict c89/c9x
* conformance experiment and to avoid a public interface delta.
*/
assert(sizeof bb16 == sizeof *bb);
memcpy(bb16, bb, sizeof bb16);
for (i = 0; our_int16s[i]; ++i) {
j = BB_ADJUST_OFFSET + our_int16s[i];
if (bb16[j]) {
warnx("non-zero bits %04x in bytes %d..%d",
bb16[j], j * 2, j * 2 + 1);
bb16[j] = 0;
resum(bb, bb16);
}
}
/*
* Make alpha checksum <47:32> come out to the sun magic.
*/
bb16[BB_ADJUST_OFFSET + 2] = htons(SUN_DKMAGIC) - bb16[254];
resum(bb, bb16);
sunsum = compute_sparc(bb16); /* might be the final value */
if (verbose)
printf("target sun checksum is %04x\n", sunsum);
/*
* Arrange to have alpha 63:48 add up to the sparc checksum.
*/
chkdelta = sunsum - bb16[255];
bb16[BB_ADJUST_OFFSET + 3] = chkdelta >> 1;
bb16[BB_ADJUST_OFFSET + 7] = chkdelta >> 1;
/*
* By placing half the correction in two different u_int64_t words at
* positions 63:48, the sparc sum will not change but the alpha sum
* will have the full correction, but only if the target adjustment
* was even. If it was odd, reverse propagate the carry one place.
*/
if (chkdelta & 1) {
if (verbose)
printf("target adjustment %04x was odd, correcting\n",
chkdelta);
assert(bb16[BB_ADJUST_OFFSET + 6] == 0);
assert(bb16[BB_ADJUST_OFFSET + 012] == 0);
bb16[BB_ADJUST_OFFSET + 6] += 0x8000;
bb16[BB_ADJUST_OFFSET + 012] += 0x8000;
}
resum(bb, bb16);
if (verbose)
printf("final harmonized checksum: %016llx\n",
(long long)bb->bb_cksum);
check_sparc(bb, "final");
}
void
check_sparc(const struct boot_block * const bb, const char *when)
{
u_int16_t bb16[256];
const char * const wmsg = "warning, %s sparc %s 0x%04x invalid,"
" expected 0x%04x";
memcpy(bb16, bb, sizeof bb16);
if (compute_sparc(bb16) != bb16[255])
warnx(wmsg, when, "checksum", bb16[255], compute_sparc(bb16));
if (bb16[254] != htons(SUN_DKMAGIC))
warnx(wmsg, when, "magic number", bb16[254],
htons(SUN_DKMAGIC));
}
static u_int16_t
compute_sparc(const u_int16_t *bb16)
{
u_int16_t i, s = 0;
for (i = 0; i < 255; ++i)
s ^= bb16[i];
return s;
}