597 lines
14 KiB
C
597 lines
14 KiB
C
/* sfs.c - Amiga Smart FileSystem. */
|
||
/*
|
||
* GRUB -- GRand Unified Bootloader
|
||
* Copyright (C) 2005,2006,2007,2008,2009 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>
|
||
#include <grub/fshelp.h>
|
||
|
||
/* The common header for a block. */
|
||
struct grub_sfs_bheader
|
||
{
|
||
grub_uint8_t magic[4];
|
||
grub_uint32_t chksum;
|
||
grub_uint32_t ipointtomyself;
|
||
} __attribute__ ((packed));
|
||
|
||
/* The sfs rootblock. */
|
||
struct grub_sfs_rblock
|
||
{
|
||
struct grub_sfs_bheader header;
|
||
grub_uint32_t version;
|
||
grub_uint8_t unused1[36];
|
||
grub_uint32_t blocksize;
|
||
grub_uint8_t unused2[40];
|
||
grub_uint8_t unused3[8];
|
||
grub_uint32_t rootobject;
|
||
grub_uint32_t btree;
|
||
} __attribute__ ((packed));
|
||
|
||
/* A SFS object container. */
|
||
struct grub_sfs_obj
|
||
{
|
||
grub_uint8_t unused1[4];
|
||
grub_uint32_t nodeid;
|
||
grub_uint8_t unused2[4];
|
||
union
|
||
{
|
||
struct
|
||
{
|
||
grub_uint32_t first_block;
|
||
grub_uint32_t size;
|
||
} file __attribute__ ((packed));
|
||
struct
|
||
{
|
||
grub_uint32_t hashtable;
|
||
grub_uint32_t dir_objc;
|
||
} dir __attribute__ ((packed));
|
||
} file_dir;
|
||
grub_uint8_t unused3[4];
|
||
grub_uint8_t type;
|
||
grub_uint8_t filename[1];
|
||
grub_uint8_t comment[1];
|
||
} __attribute__ ((packed));
|
||
|
||
#define GRUB_SFS_TYPE_DELETED 32
|
||
#define GRUB_SFS_TYPE_SYMLINK 64
|
||
#define GRUB_SFS_TYPE_DIR 128
|
||
|
||
/* A SFS object container. */
|
||
struct grub_sfs_objc
|
||
{
|
||
struct grub_sfs_bheader header;
|
||
grub_uint32_t parent;
|
||
grub_uint32_t next;
|
||
grub_uint32_t prev;
|
||
/* The amount of objects depends on the blocksize. */
|
||
struct grub_sfs_obj objects[1];
|
||
} __attribute__ ((packed));
|
||
|
||
struct grub_sfs_btree_node
|
||
{
|
||
grub_uint32_t key;
|
||
grub_uint32_t data;
|
||
} __attribute__ ((packed));
|
||
|
||
struct grub_sfs_btree_extent
|
||
{
|
||
grub_uint32_t key;
|
||
grub_uint32_t next;
|
||
grub_uint32_t prev;
|
||
grub_uint16_t size;
|
||
} __attribute__ ((packed));
|
||
|
||
struct grub_sfs_btree
|
||
{
|
||
struct grub_sfs_bheader header;
|
||
grub_uint16_t nodes;
|
||
grub_uint8_t leaf;
|
||
grub_uint8_t nodesize;
|
||
/* Normally this can be kind of node, but just extents are
|
||
supported. */
|
||
struct grub_sfs_btree_node node[1];
|
||
} __attribute__ ((packed));
|
||
|
||
|
||
|
||
struct grub_fshelp_node
|
||
{
|
||
struct grub_sfs_data *data;
|
||
int block;
|
||
int size;
|
||
};
|
||
|
||
/* Information about a "mounted" sfs filesystem. */
|
||
struct grub_sfs_data
|
||
{
|
||
struct grub_sfs_rblock rblock;
|
||
struct grub_fshelp_node diropen;
|
||
grub_disk_t disk;
|
||
|
||
/* Blocksize in sectors. */
|
||
unsigned int blocksize;
|
||
|
||
/* Label of the filesystem. */
|
||
char *label;
|
||
};
|
||
|
||
static grub_dl_t my_mod;
|
||
|
||
|
||
/* Lookup the extent starting with BLOCK in the filesystem described
|
||
by DATA. Return the extent size in SIZE and the following extent
|
||
in NEXTEXT. */
|
||
static grub_err_t
|
||
grub_sfs_read_extent (struct grub_sfs_data *data, unsigned int block,
|
||
int *size, int *nextext)
|
||
{
|
||
char *treeblock;
|
||
struct grub_sfs_btree *tree;
|
||
int i;
|
||
int next;
|
||
int prev;
|
||
|
||
treeblock = grub_malloc (data->blocksize);
|
||
if (!block)
|
||
return 0;
|
||
|
||
next = grub_be_to_cpu32 (data->rblock.btree);
|
||
tree = (struct grub_sfs_btree *) treeblock;
|
||
|
||
/* Handle this level in the btree. */
|
||
do
|
||
{
|
||
prev = 0;
|
||
|
||
grub_disk_read (data->disk, next, 0, data->blocksize, treeblock);
|
||
if (grub_errno)
|
||
{
|
||
grub_free (treeblock);
|
||
return grub_errno;
|
||
}
|
||
|
||
for (i = grub_be_to_cpu16 (tree->nodes) - 1; i >= 0; i--)
|
||
{
|
||
|
||
#define EXTNODE(tree, index) \
|
||
((struct grub_sfs_btree_node *) (((char *) &(tree)->node[0]) \
|
||
+ (index) * (tree)->nodesize))
|
||
|
||
/* Follow the tree down to the leaf level. */
|
||
if ((grub_be_to_cpu32 (EXTNODE(tree, i)->key) <= block)
|
||
&& !tree->leaf)
|
||
{
|
||
next = grub_be_to_cpu32 (EXTNODE (tree, i)->data);
|
||
break;
|
||
}
|
||
|
||
/* If the leaf level is reached, just find the correct extent. */
|
||
if (grub_be_to_cpu32 (EXTNODE (tree, i)->key) == block && tree->leaf)
|
||
{
|
||
struct grub_sfs_btree_extent *extent;
|
||
extent = (struct grub_sfs_btree_extent *) EXTNODE (tree, i);
|
||
|
||
/* We found a correct leaf. */
|
||
*size = grub_be_to_cpu16 (extent->size);
|
||
*nextext = grub_be_to_cpu32 (extent->next);
|
||
|
||
grub_free (treeblock);
|
||
return 0;
|
||
}
|
||
|
||
#undef EXTNODE
|
||
|
||
}
|
||
} while (!tree->leaf);
|
||
|
||
grub_free (treeblock);
|
||
|
||
return grub_error (GRUB_ERR_FILE_READ_ERROR, "SFS extent not found");
|
||
}
|
||
|
||
static grub_disk_addr_t
|
||
grub_sfs_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
|
||
{
|
||
int blk = node->block;
|
||
int size = 0;
|
||
int next = 0;
|
||
|
||
while (blk)
|
||
{
|
||
grub_err_t err;
|
||
|
||
/* In case of the first block we don't have to lookup the
|
||
extent, the minimum size is always 1. */
|
||
if (fileblock == 0)
|
||
return blk;
|
||
|
||
err = grub_sfs_read_extent (node->data, blk, &size, &next);
|
||
if (err)
|
||
return 0;
|
||
|
||
if (fileblock < (unsigned int) size)
|
||
return fileblock + blk;
|
||
|
||
fileblock -= size;
|
||
|
||
blk = next;
|
||
}
|
||
|
||
grub_error (GRUB_ERR_FILE_READ_ERROR,
|
||
"reading a SFS block outside the extent");
|
||
|
||
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_sfs_read_file (grub_fshelp_node_t node,
|
||
void NESTED_FUNC_ATTR (*read_hook) (grub_disk_addr_t sector,
|
||
unsigned offset, unsigned length),
|
||
int pos, grub_size_t len, char *buf)
|
||
{
|
||
return grub_fshelp_read_file (node->data->disk, node, read_hook,
|
||
pos, len, buf, grub_sfs_read_block,
|
||
node->size, 0);
|
||
}
|
||
|
||
|
||
static struct grub_sfs_data *
|
||
grub_sfs_mount (grub_disk_t disk)
|
||
{
|
||
struct grub_sfs_data *data;
|
||
struct grub_sfs_objc *rootobjc;
|
||
char *rootobjc_data = 0;
|
||
unsigned int blk;
|
||
|
||
data = grub_malloc (sizeof (*data));
|
||
if (!data)
|
||
return 0;
|
||
|
||
/* Read the rootblock. */
|
||
grub_disk_read (disk, 0, 0, sizeof (struct grub_sfs_rblock),
|
||
&data->rblock);
|
||
if (grub_errno)
|
||
goto fail;
|
||
|
||
/* Make sure this is a sfs filesystem. */
|
||
if (grub_strncmp ((char *) (data->rblock.header.magic), "SFS", 4))
|
||
{
|
||
grub_error (GRUB_ERR_BAD_FS, "not a SFS filesystem");
|
||
goto fail;
|
||
}
|
||
|
||
data->blocksize = grub_be_to_cpu32 (data->rblock.blocksize);
|
||
rootobjc_data = grub_malloc (data->blocksize);
|
||
if (! rootobjc_data)
|
||
goto fail;
|
||
|
||
/* Read the root object container. */
|
||
grub_disk_read (disk, grub_be_to_cpu32 (data->rblock.rootobject), 0,
|
||
data->blocksize, rootobjc_data);
|
||
if (grub_errno)
|
||
goto fail;
|
||
|
||
rootobjc = (struct grub_sfs_objc *) rootobjc_data;
|
||
|
||
blk = grub_be_to_cpu32 (rootobjc->objects[0].file_dir.dir.dir_objc);
|
||
data->diropen.size = 0;
|
||
data->diropen.block = blk;
|
||
data->diropen.data = data;
|
||
data->disk = disk;
|
||
data->label = grub_strdup ((char *) (rootobjc->objects[0].filename));
|
||
|
||
return data;
|
||
|
||
fail:
|
||
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
|
||
grub_error (GRUB_ERR_BAD_FS, "not an SFS filesystem");
|
||
|
||
grub_free (data);
|
||
grub_free (rootobjc_data);
|
||
return 0;
|
||
}
|
||
|
||
|
||
static char *
|
||
grub_sfs_read_symlink (grub_fshelp_node_t node)
|
||
{
|
||
struct grub_sfs_data *data = node->data;
|
||
char *symlink;
|
||
char *block;
|
||
|
||
block = grub_malloc (data->blocksize);
|
||
if (!block)
|
||
return 0;
|
||
|
||
grub_disk_read (data->disk, node->block, 0, data->blocksize, block);
|
||
if (grub_errno)
|
||
{
|
||
grub_free (block);
|
||
return 0;
|
||
}
|
||
|
||
/* This is just a wild guess, but it always worked for me. How the
|
||
SLNK block looks like is not documented in the SFS docs. */
|
||
symlink = grub_strdup (&block[24]);
|
||
grub_free (block);
|
||
if (!symlink)
|
||
return 0;
|
||
|
||
return symlink;
|
||
}
|
||
|
||
static int
|
||
grub_sfs_iterate_dir (grub_fshelp_node_t dir,
|
||
int NESTED_FUNC_ATTR
|
||
(*hook) (const char *filename,
|
||
enum grub_fshelp_filetype filetype,
|
||
grub_fshelp_node_t node))
|
||
{
|
||
struct grub_fshelp_node *node = 0;
|
||
struct grub_sfs_data *data = dir->data;
|
||
char *objc_data;
|
||
struct grub_sfs_objc *objc;
|
||
unsigned int next = dir->block;
|
||
int pos;
|
||
|
||
auto int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
|
||
int size, int type);
|
||
|
||
int NESTED_FUNC_ATTR grub_sfs_create_node (const char *name, int block,
|
||
int size, int type)
|
||
{
|
||
node = grub_malloc (sizeof (*node));
|
||
if (!node)
|
||
return 1;
|
||
|
||
node->data = data;
|
||
node->size = size;
|
||
node->block = block;
|
||
|
||
return hook (name, type, node);
|
||
}
|
||
|
||
objc_data = grub_malloc (data->blocksize);
|
||
if (!objc_data)
|
||
goto fail;
|
||
|
||
/* The Object container can consist of multiple blocks, iterate over
|
||
every block. */
|
||
while (next)
|
||
{
|
||
grub_disk_read (data->disk, next, 0, data->blocksize, objc_data);
|
||
if (grub_errno)
|
||
goto fail;
|
||
|
||
objc = (struct grub_sfs_objc *) objc_data;
|
||
|
||
pos = (char *) &objc->objects[0] - (char *) objc;
|
||
|
||
/* Iterate over all entries in this block. */
|
||
while (pos + sizeof (struct grub_sfs_obj) < data->blocksize)
|
||
{
|
||
struct grub_sfs_obj *obj;
|
||
obj = (struct grub_sfs_obj *) ((char *) objc + pos);
|
||
char *filename = (char *) (obj->filename);
|
||
int len;
|
||
enum grub_fshelp_filetype type;
|
||
unsigned int block;
|
||
|
||
/* The filename and comment dynamically increase the size of
|
||
the object. */
|
||
len = grub_strlen (filename);
|
||
len += grub_strlen (filename + len + 1);
|
||
|
||
pos += sizeof (*obj) + len;
|
||
/* Round up to a multiple of two bytes. */
|
||
pos = ((pos + 1) >> 1) << 1;
|
||
|
||
if (grub_strlen (filename) == 0)
|
||
continue;
|
||
|
||
/* First check if the file was not deleted. */
|
||
if (obj->type & GRUB_SFS_TYPE_DELETED)
|
||
continue;
|
||
else if (obj->type & GRUB_SFS_TYPE_SYMLINK)
|
||
type = GRUB_FSHELP_SYMLINK;
|
||
else if (obj->type & GRUB_SFS_TYPE_DIR)
|
||
type = GRUB_FSHELP_DIR;
|
||
else
|
||
type = GRUB_FSHELP_REG;
|
||
|
||
if (type == GRUB_FSHELP_DIR)
|
||
block = grub_be_to_cpu32 (obj->file_dir.dir.dir_objc);
|
||
else
|
||
block = grub_be_to_cpu32 (obj->file_dir.file.first_block);
|
||
|
||
if (grub_sfs_create_node (filename, block,
|
||
grub_be_to_cpu32 (obj->file_dir.file.size),
|
||
type))
|
||
{
|
||
grub_free (objc_data);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
next = grub_be_to_cpu32 (objc->next);
|
||
}
|
||
|
||
fail:
|
||
grub_free (objc_data);
|
||
return 0;
|
||
}
|
||
|
||
|
||
/* Open a file named NAME and initialize FILE. */
|
||
static grub_err_t
|
||
grub_sfs_open (struct grub_file *file, const char *name)
|
||
{
|
||
struct grub_sfs_data *data;
|
||
struct grub_fshelp_node *fdiro = 0;
|
||
|
||
grub_dl_ref (my_mod);
|
||
|
||
data = grub_sfs_mount (file->device->disk);
|
||
if (!data)
|
||
goto fail;
|
||
|
||
grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_sfs_iterate_dir,
|
||
grub_sfs_read_symlink, GRUB_FSHELP_REG);
|
||
if (grub_errno)
|
||
goto fail;
|
||
|
||
file->size = fdiro->size;
|
||
data->diropen = *fdiro;
|
||
grub_free (fdiro);
|
||
|
||
file->data = data;
|
||
file->offset = 0;
|
||
|
||
return 0;
|
||
|
||
fail:
|
||
if (data && fdiro != &data->diropen)
|
||
grub_free (fdiro);
|
||
if (data)
|
||
grub_free (data->label);
|
||
grub_free (data);
|
||
|
||
grub_dl_unref (my_mod);
|
||
|
||
return grub_errno;
|
||
}
|
||
|
||
|
||
static grub_err_t
|
||
grub_sfs_close (grub_file_t file)
|
||
{
|
||
grub_free (file->data);
|
||
|
||
grub_dl_unref (my_mod);
|
||
|
||
return GRUB_ERR_NONE;
|
||
}
|
||
|
||
|
||
/* Read LEN bytes data from FILE into BUF. */
|
||
static grub_ssize_t
|
||
grub_sfs_read (grub_file_t file, char *buf, grub_size_t len)
|
||
{
|
||
struct grub_sfs_data *data = (struct grub_sfs_data *) file->data;
|
||
|
||
int size = grub_sfs_read_file (&data->diropen, file->read_hook,
|
||
file->offset, len, buf);
|
||
|
||
return size;
|
||
}
|
||
|
||
|
||
static grub_err_t
|
||
grub_sfs_dir (grub_device_t device, const char *path,
|
||
int (*hook) (const char *filename,
|
||
const struct grub_dirhook_info *info))
|
||
{
|
||
struct grub_sfs_data *data = 0;
|
||
struct grub_fshelp_node *fdiro = 0;
|
||
|
||
auto int NESTED_FUNC_ATTR iterate (const char *filename,
|
||
enum grub_fshelp_filetype filetype,
|
||
grub_fshelp_node_t node);
|
||
|
||
int NESTED_FUNC_ATTR iterate (const char *filename,
|
||
enum grub_fshelp_filetype filetype,
|
||
grub_fshelp_node_t node)
|
||
{
|
||
struct grub_dirhook_info info;
|
||
grub_memset (&info, 0, sizeof (info));
|
||
info.dir = ((filetype & GRUB_FSHELP_TYPE_MASK) == GRUB_FSHELP_DIR);
|
||
grub_free (node);
|
||
return hook (filename, &info);
|
||
}
|
||
|
||
grub_dl_ref (my_mod);
|
||
|
||
data = grub_sfs_mount (device->disk);
|
||
if (!data)
|
||
goto fail;
|
||
|
||
grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_sfs_iterate_dir,
|
||
grub_sfs_read_symlink, GRUB_FSHELP_DIR);
|
||
if (grub_errno)
|
||
goto fail;
|
||
|
||
grub_sfs_iterate_dir (fdiro, iterate);
|
||
|
||
fail:
|
||
if (data && fdiro != &data->diropen)
|
||
grub_free (fdiro);
|
||
if (data)
|
||
grub_free (data->label);
|
||
grub_free (data);
|
||
|
||
grub_dl_unref (my_mod);
|
||
|
||
return grub_errno;
|
||
}
|
||
|
||
|
||
static grub_err_t
|
||
grub_sfs_label (grub_device_t device, char **label)
|
||
{
|
||
struct grub_sfs_data *data;
|
||
grub_disk_t disk = device->disk;
|
||
|
||
data = grub_sfs_mount (disk);
|
||
if (data)
|
||
*label = data->label;
|
||
|
||
grub_free (data);
|
||
|
||
return grub_errno;
|
||
}
|
||
|
||
|
||
static struct grub_fs grub_sfs_fs =
|
||
{
|
||
.name = "sfs",
|
||
.dir = grub_sfs_dir,
|
||
.open = grub_sfs_open,
|
||
.read = grub_sfs_read,
|
||
.close = grub_sfs_close,
|
||
.label = grub_sfs_label,
|
||
.next = 0
|
||
};
|
||
|
||
GRUB_MOD_INIT(sfs)
|
||
{
|
||
grub_fs_register (&grub_sfs_fs);
|
||
my_mod = mod;
|
||
}
|
||
|
||
GRUB_MOD_FINI(sfs)
|
||
{
|
||
grub_fs_unregister (&grub_sfs_fs);
|
||
}
|