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#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <errno.h>
#include <sys/stat.h>
#include <limits.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include "installboot.h"
#ifndef DFL_SECSIZE
#define DFL_SECSIZE 512
#endif
#define MFS_FIRST_SUBP_OFFSET 32
enum {
TYPE_BAD,
TYPE_PART,
TYPE_DISK
};
static int
minixfs3_read_mbr(const char* device, char* buf)
{
int fd;
int bytes;
int n;
fd = open(device, O_RDONLY);
if (fd == -1) {
fprintf(stderr, "Can't open %s: %s\n", device, strerror(errno));
return 1;
}
if (lseek(fd, MBR_PART_OFFSET, SEEK_SET) != MBR_PART_OFFSET) {
fprintf(stderr, "Can't seek in %s to %d: %s\n",
device, MBR_PART_OFFSET, strerror(errno));
close(fd);
return 1;
}
bytes = DFL_SECSIZE - MBR_PART_OFFSET;
if ((n = read(fd, buf, bytes)) != bytes) {
fprintf(stderr, "Can't read %d bytes from %s, %d read instead"
": %s\n",
bytes, device, n, strerror(errno));
close(fd);
return 1;
}
if ((uint8_t)buf[bytes-2] != 0x55 || (uint8_t)buf[bytes-1] != 0xAA) {
fprintf(stderr, "No MBR on %s, signature is %x\n",
device, *(uint16_t*)(&buf[bytes-2]));
close(fd);
return 1;
}
close(fd);
return 0;
}
static int
minixfs3_get_dev_type(const char *device, ib_params *params)
{
int len, type;
/*
* Unless the -f flag is given, we expect to be provided with a primary
* partition. That is, a device name that ends with "pN", N being 0-3.
* If the -f flag is given, we assume that anything else is a whole
* disk. If we were given a subpartition, it will fail the subsequent
* MBR signature test, so we need not check this explicitly.
*/
len = strlen(device);
if (len > 2 && device[len-2] == 'p' &&
(unsigned) (device[len-1] - '0') <= 3) {
type = TYPE_PART;
} else {
type = TYPE_DISK;
}
if (type != TYPE_PART && !(params->flags & IB_FORCE)) {
fprintf(stderr, "Wrong device %s, must be /.../cxdyp[0-3]\n",
device);
return TYPE_BAD;
}
return type;
}
int
minixfs3_is_minix_partition(ib_params *params)
{
char buf[DFL_SECSIZE]; /* part table + signature */
if (minixfs3_get_dev_type(params->filesystem, params) == TYPE_BAD)
return 0;
/* MINIX 3 partition with current scheme *must* have subpartitions,
* thus MBR has signature. minixfs3_read_mbr checks the signature.
*/
if (minixfs3_read_mbr(params->filesystem, buf))
return 0;
return 1;
}
/* bootxx from NetBSD is ~8Kb, and old MINIX installations have just
* 1Kb of space for their bootblock. Check if there is enough space
* to install bootxx_minixfs3. New installation should have 16Kb before
* the first subpartition.
*/
int
minixfs3_has_bootblock_space(ib_params *params)
{
const char *device;
char buf[DFL_SECSIZE]; /* part table + signature */
char parent_name[NAME_MAX];
struct mbr_partition *part;
uint32_t first_subpartition = (uint32_t) ~0;
uint32_t parent_partition;
int i, len, type = 0;
device = params->filesystem;
if ((type = minixfs3_get_dev_type(device, params)) == TYPE_BAD)
exit(1);
if (minixfs3_read_mbr(device, buf))
exit(1);
part = (struct mbr_partition *) buf;
for (i = 0; i < 4; i++) {
if (part[i].mbrp_size &&
part[i].mbrp_start < first_subpartition)
first_subpartition = part[i].mbrp_start;
}
if (type == TYPE_PART) {
/* The target is a partition. Look up its starting offset. */
len = strlen(device);
strncpy(parent_name, device, len - 2);
parent_name[len - 2] = '\0';
if (minixfs3_read_mbr(parent_name, buf))
exit(1);
parent_partition = 0;
for (i = 0; i < 4; i++) {
struct mbr_partition *p = &part[i];
if (p->mbrp_size && p->mbrp_start <= first_subpartition
&& (p->mbrp_start + p->mbrp_size) >
first_subpartition) {
parent_partition = p->mbrp_start;
break;
}
}
} else {
/* The target is a whole disk. The starting offset is 0. */
parent_partition = 0;
}
if ((first_subpartition - parent_partition) < MFS_FIRST_SUBP_OFFSET)
return 0;
else
return 1;
}
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