grub/grub-core/fs/minix.c
Vladimir 'phcoder' Serbinenko e745cf0ca6 Implement automatic module license checking according to new GNU
guidelines.

	* grub-core/kern/dl.c (grub_dl_check_license): New function.
	(grub_dl_load_core): Use grub_dl_check_license.
	* include/grub/dl.h (GRUB_MOD_SECTION): New macro.
	(GRUB_MOD_LICENSE): Likewise.
	(GRUB_MOD_DUAL_LICENSE): Likewise.
	All modules updated.
2011-04-11 23:01:51 +02:00

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/* minix.c - The minix filesystem, version 1 and 2. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2004,2005,2006,2007,2008 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/err.h>
#include <grub/file.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/disk.h>
#include <grub/dl.h>
#include <grub/types.h>
GRUB_MOD_LICENSE ("GPLv3+");
#ifdef MODE_MINIX2
#define GRUB_MINIX_MAGIC 0x2468
#define GRUB_MINIX_MAGIC_30 0x2478
#else
#define GRUB_MINIX_MAGIC 0x137F
#define GRUB_MINIX_MAGIC_30 0x138F
#endif
#define GRUB_MINIX_BSIZE 1024U
#define GRUB_MINIX_LOG2_BSIZE 1
#define GRUB_MINIX_ROOT_INODE 1
#define GRUB_MINIX_MAX_SYMLNK_CNT 8
#define GRUB_MINIX_SBLOCK 2
#define GRUB_MINIX_IFDIR 0040000U
#define GRUB_MINIX_IFLNK 0120000U
#ifdef MODE_MINIX2
typedef grub_uint32_t grub_minix_uintn_t;
#define grub_minix_le_to_cpu_n grub_le_to_cpu32
#else
typedef grub_uint16_t grub_minix_uintn_t;
#define grub_minix_le_to_cpu_n grub_le_to_cpu16
#endif
#define GRUB_MINIX_INODE_BLKSZ(data) sizeof (grub_minix_uintn_t)
#define GRUB_MINIX_INODE_SIZE(data) (grub_minix_le_to_cpu_n (data->inode.size))
#define GRUB_MINIX_INODE_MODE(data) (grub_le_to_cpu16 (data->inode.mode))
#define GRUB_MINIX_INODE_DIR_ZONES(data,blk) (grub_minix_le_to_cpu_n \
(data->inode.dir_zones[blk]))
#define GRUB_MINIX_INODE_INDIR_ZONE(data) (grub_minix_le_to_cpu_n \
(data->inode.indir_zone))
#define GRUB_MINIX_INODE_DINDIR_ZONE(data) (grub_minix_le_to_cpu_n \
(data->inode.double_indir_zone))
#define GRUB_MINIX_LOG2_ZONESZ (GRUB_MINIX_LOG2_BSIZE \
+ grub_le_to_cpu16 (sblock->log2_zone_size))
#define GRUB_MINIX_ZONESZ (GRUB_MINIX_BSIZE \
<< grub_le_to_cpu16 (sblock->log2_zone_size))
struct grub_minix_sblock
{
grub_uint16_t inode_cnt;
grub_uint16_t zone_cnt;
grub_uint16_t inode_bmap_size;
grub_uint16_t zone_bmap_size;
grub_uint16_t first_data_zone;
grub_uint16_t log2_zone_size;
grub_uint32_t max_file_size;
grub_uint16_t magic;
};
#ifndef MODE_MINIX2
struct grub_minix_inode
{
grub_uint16_t mode;
grub_uint16_t uid;
grub_uint16_t size;
grub_uint32_t ctime;
grub_uint8_t gid;
grub_uint8_t nlinks;
grub_uint16_t dir_zones[7];
grub_uint16_t indir_zone;
grub_uint16_t double_indir_zone;
};
#else
struct grub_minix_inode
{
grub_uint16_t mode;
grub_uint16_t nlinks;
grub_uint16_t uid;
grub_uint16_t gid;
grub_uint32_t size;
grub_uint32_t atime;
grub_uint32_t mtime;
grub_uint32_t ctime;
grub_uint32_t dir_zones[7];
grub_uint32_t indir_zone;
grub_uint32_t double_indir_zone;
grub_uint32_t unused;
};
#endif
/* Information about a "mounted" minix filesystem. */
struct grub_minix_data
{
struct grub_minix_sblock sblock;
struct grub_minix_inode inode;
int ino;
int linknest;
grub_disk_t disk;
int filename_size;
};
static grub_dl_t my_mod;
static grub_err_t grub_minix_find_file (struct grub_minix_data *data,
const char *path);
static int
grub_minix_get_file_block (struct grub_minix_data *data, unsigned int blk)
{
struct grub_minix_sblock *sblock = &data->sblock;
int indir;
auto int grub_get_indir (int, int);
/* Read the block pointer in ZONE, on the offset NUM. */
int grub_get_indir (int zone, int num)
{
grub_minix_uintn_t indirn;
grub_disk_read (data->disk,
zone << GRUB_MINIX_LOG2_ZONESZ,
sizeof (grub_minix_uintn_t) * num,
sizeof (grub_minix_uintn_t), (char *) &indirn);
return grub_minix_le_to_cpu_n (indirn);
}
/* Direct block. */
if (blk < 7)
return GRUB_MINIX_INODE_DIR_ZONES (data, blk);
/* Indirect block. */
blk -= 7;
if (blk < GRUB_MINIX_ZONESZ / GRUB_MINIX_INODE_BLKSZ (data))
{
indir = grub_get_indir (GRUB_MINIX_INODE_INDIR_ZONE (data), blk);
return indir;
}
/* Double indirect block. */
blk -= GRUB_MINIX_ZONESZ / GRUB_MINIX_INODE_BLKSZ (data);
if (blk < (GRUB_MINIX_ZONESZ / GRUB_MINIX_INODE_BLKSZ (data))
* (GRUB_MINIX_ZONESZ / GRUB_MINIX_INODE_BLKSZ (data)))
{
indir = grub_get_indir (GRUB_MINIX_INODE_DINDIR_ZONE (data),
blk / GRUB_MINIX_ZONESZ);
indir = grub_get_indir (indir, blk % GRUB_MINIX_ZONESZ);
return indir;
}
/* This should never happen. */
grub_error (GRUB_ERR_OUT_OF_RANGE, "file bigger than maximum size");
return 0;
}
/* Read LEN bytes from the file described by DATA starting with byte
POS. Return the amount of read bytes in READ. */
static grub_ssize_t
grub_minix_read_file (struct grub_minix_data *data,
void NESTED_FUNC_ATTR (*read_hook) (grub_disk_addr_t sector,
unsigned offset, unsigned length),
int pos, grub_disk_addr_t len, char *buf)
{
struct grub_minix_sblock *sblock = &data->sblock;
int i;
int blockcnt;
/* Adjust len so it we can't read past the end of the file. */
if (len + pos > GRUB_MINIX_INODE_SIZE (data))
len = GRUB_MINIX_INODE_SIZE (data) - pos;
blockcnt = (len + pos + GRUB_MINIX_BSIZE - 1) / GRUB_MINIX_BSIZE;
for (i = pos / GRUB_MINIX_BSIZE; i < blockcnt; i++)
{
int blknr;
int blockoff = pos % GRUB_MINIX_BSIZE;
int blockend = GRUB_MINIX_BSIZE;
int skipfirst = 0;
blknr = grub_minix_get_file_block (data, i);
if (grub_errno)
return -1;
/* Last block. */
if (i == blockcnt - 1)
{
blockend = (len + pos) % GRUB_MINIX_BSIZE;
if (!blockend)
blockend = GRUB_MINIX_BSIZE;
}
/* First block. */
if (i == (pos / (int) GRUB_MINIX_BSIZE))
{
skipfirst = blockoff;
blockend -= skipfirst;
}
data->disk->read_hook = read_hook;
grub_disk_read (data->disk, blknr << GRUB_MINIX_LOG2_ZONESZ,
skipfirst, blockend, buf);
data->disk->read_hook = 0;
if (grub_errno)
return -1;
buf += GRUB_MINIX_BSIZE - skipfirst;
}
return len;
}
/* Read inode INO from the mounted filesystem described by DATA. This
inode is used by default now. */
static grub_err_t
grub_minix_read_inode (struct grub_minix_data *data, int ino)
{
struct grub_minix_sblock *sblock = &data->sblock;
/* Block in which the inode is stored. */
int block;
data->ino = ino;
/* The first inode in minix is inode 1. */
ino--;
block = ((2 + grub_le_to_cpu16 (sblock->inode_bmap_size)
+ grub_le_to_cpu16 (sblock->zone_bmap_size))
<< GRUB_MINIX_LOG2_BSIZE);
block += ino / (GRUB_DISK_SECTOR_SIZE / sizeof (struct grub_minix_inode));
int offs = (ino % (GRUB_DISK_SECTOR_SIZE
/ sizeof (struct grub_minix_inode))
* sizeof (struct grub_minix_inode));
grub_disk_read (data->disk, block, offs,
sizeof (struct grub_minix_inode), &data->inode);
return GRUB_ERR_NONE;
}
/* Lookup the symlink the current inode points to. INO is the inode
number of the directory the symlink is relative to. */
static grub_err_t
grub_minix_lookup_symlink (struct grub_minix_data *data, int ino)
{
char symlink[GRUB_MINIX_INODE_SIZE (data) + 1];
if (++data->linknest > GRUB_MINIX_MAX_SYMLNK_CNT)
return grub_error (GRUB_ERR_SYMLINK_LOOP, "too deep nesting of symlinks");
if (grub_minix_read_file (data, 0, 0,
GRUB_MINIX_INODE_SIZE (data), symlink) < 0)
return grub_errno;
symlink[GRUB_MINIX_INODE_SIZE (data)] = '\0';
/* The symlink is an absolute path, go back to the root inode. */
if (symlink[0] == '/')
ino = GRUB_MINIX_ROOT_INODE;
/* Now load in the old inode. */
if (grub_minix_read_inode (data, ino))
return grub_errno;
grub_minix_find_file (data, symlink);
if (grub_errno)
grub_error (grub_errno, "cannot follow symlink `%s'", symlink);
return grub_errno;
}
/* Find the file with the pathname PATH on the filesystem described by
DATA. */
static grub_err_t
grub_minix_find_file (struct grub_minix_data *data, const char *path)
{
char fpath[grub_strlen (path) + 1];
char *name = fpath;
char *next;
unsigned int pos = 0;
int dirino;
grub_strcpy (fpath, path);
/* Skip the first slash. */
if (name[0] == '/')
{
name++;
if (!*name)
return 0;
}
/* Extract the actual part from the pathname. */
next = grub_strchr (name, '/');
if (next)
{
next[0] = '\0';
next++;
}
do
{
grub_uint16_t ino;
char filename[data->filename_size + 1];
if (grub_strlen (name) == 0)
return GRUB_ERR_NONE;
if (grub_minix_read_file (data, 0, pos, sizeof (ino),
(char *) &ino) < 0)
return grub_errno;
if (grub_minix_read_file (data, 0, pos + sizeof (ino),
data->filename_size, (char *) filename)< 0)
return grub_errno;
filename[data->filename_size] = '\0';
/* Check if the current direntry matches the current part of the
pathname. */
if (!grub_strcmp (name, filename))
{
dirino = data->ino;
grub_minix_read_inode (data, grub_le_to_cpu16 (ino));
/* Follow the symlink. */
if ((GRUB_MINIX_INODE_MODE (data)
& GRUB_MINIX_IFLNK) == GRUB_MINIX_IFLNK)
{
grub_minix_lookup_symlink (data, dirino);
if (grub_errno)
return grub_errno;
}
if (!next)
return 0;
pos = 0;
name = next;
next = grub_strchr (name, '/');
if (next)
{
next[0] = '\0';
next++;
}
if ((GRUB_MINIX_INODE_MODE (data)
& GRUB_MINIX_IFDIR) != GRUB_MINIX_IFDIR)
return grub_error (GRUB_ERR_BAD_FILE_TYPE, "not a directory");
continue;
}
pos += sizeof (ino) + data->filename_size;
} while (pos < GRUB_MINIX_INODE_SIZE (data));
grub_error (GRUB_ERR_FILE_NOT_FOUND, "file not found");
return grub_errno;
}
/* Mount the filesystem on the disk DISK. */
static struct grub_minix_data *
grub_minix_mount (grub_disk_t disk)
{
struct grub_minix_data *data;
data = grub_malloc (sizeof (struct grub_minix_data));
if (!data)
return 0;
/* Read the superblock. */
grub_disk_read (disk, GRUB_MINIX_SBLOCK, 0,
sizeof (struct grub_minix_sblock),&data->sblock);
if (grub_errno)
goto fail;
if (grub_le_to_cpu16 (data->sblock.magic) == GRUB_MINIX_MAGIC)
data->filename_size = 14;
else if (grub_le_to_cpu16 (data->sblock.magic) == GRUB_MINIX_MAGIC_30)
data->filename_size = 30;
else
goto fail;
data->disk = disk;
data->linknest = 0;
return data;
fail:
grub_free (data);
#ifdef MODE_MINIX2
grub_error (GRUB_ERR_BAD_FS, "not a minix2 filesystem");
#else
grub_error (GRUB_ERR_BAD_FS, "not a minix filesystem");
#endif
return 0;
}
static grub_err_t
grub_minix_dir (grub_device_t device, const char *path,
int (*hook) (const char *filename,
const struct grub_dirhook_info *info))
{
struct grub_minix_data *data = 0;
unsigned int pos = 0;
data = grub_minix_mount (device->disk);
if (!data)
return grub_errno;
grub_minix_read_inode (data, GRUB_MINIX_ROOT_INODE);
if (grub_errno)
goto fail;
grub_minix_find_file (data, path);
if (grub_errno)
goto fail;
if ((GRUB_MINIX_INODE_MODE (data) & GRUB_MINIX_IFDIR) != GRUB_MINIX_IFDIR)
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, "not a directory");
goto fail;
}
while (pos < GRUB_MINIX_INODE_SIZE (data))
{
grub_uint16_t ino;
char filename[data->filename_size + 1];
int dirino = data->ino;
struct grub_dirhook_info info;
grub_memset (&info, 0, sizeof (info));
if (grub_minix_read_file (data, 0, pos, sizeof (ino),
(char *) &ino) < 0)
return grub_errno;
if (grub_minix_read_file (data, 0, pos + sizeof (ino),
data->filename_size,
(char *) filename) < 0)
return grub_errno;
filename[data->filename_size] = '\0';
/* The filetype is not stored in the dirent. Read the inode to
find out the filetype. This *REALLY* sucks. */
grub_minix_read_inode (data, grub_le_to_cpu16 (ino));
info.dir = ((GRUB_MINIX_INODE_MODE (data)
& GRUB_MINIX_IFDIR) == GRUB_MINIX_IFDIR);
if (hook (filename, &info) ? 1 : 0)
break;
/* Load the old inode back in. */
grub_minix_read_inode (data, dirino);
pos += sizeof (ino) + data->filename_size;
}
fail:
grub_free (data);
return grub_errno;
}
/* Open a file named NAME and initialize FILE. */
static grub_err_t
grub_minix_open (struct grub_file *file, const char *name)
{
struct grub_minix_data *data;
data = grub_minix_mount (file->device->disk);
if (!data)
return grub_errno;
/* Open the inode op the root directory. */
grub_minix_read_inode (data, GRUB_MINIX_ROOT_INODE);
if (grub_errno)
{
grub_free (data);
return grub_errno;
}
if (!name || name[0] != '/')
{
grub_error (GRUB_ERR_BAD_FILENAME, "bad filename");
return grub_errno;
}
/* Traverse the directory tree to the node that should be
opened. */
grub_minix_find_file (data, name);
if (grub_errno)
{
grub_free (data);
return grub_errno;
}
file->data = data;
file->size = GRUB_MINIX_INODE_SIZE (data);
return GRUB_ERR_NONE;
}
static grub_ssize_t
grub_minix_read (grub_file_t file, char *buf, grub_size_t len)
{
struct grub_minix_data *data =
(struct grub_minix_data *) file->data;
return grub_minix_read_file (data, file->read_hook, file->offset, len, buf);
}
static grub_err_t
grub_minix_close (grub_file_t file)
{
grub_free (file->data);
return GRUB_ERR_NONE;
}
static struct grub_fs grub_minix_fs =
{
#ifdef MODE_MINIX2
.name = "minix2",
#else
.name = "minix",
#endif
.dir = grub_minix_dir,
.open = grub_minix_open,
.read = grub_minix_read,
.close = grub_minix_close,
.next = 0
};
#ifdef MODE_MINIX2
GRUB_MOD_INIT(minix2)
#else
GRUB_MOD_INIT(minix)
#endif
{
grub_fs_register (&grub_minix_fs);
my_mod = mod;
}
#ifdef MODE_MINIX2
GRUB_MOD_FINI(minix2)
#else
GRUB_MOD_FINI(minix)
#endif
{
grub_fs_unregister (&grub_minix_fs);
}