vaseboot/VasEBoot-core/fs/affs.c

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/* affs.c - Amiga Fast FileSystem. */
/*
* VAS_EBOOT -- GRand Unified Bootloader
* Copyright (C) 2005,2006,2007,2008,2009 Free Software Foundation, Inc.
*
* VAS_EBOOT 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.
*
* VAS_EBOOT 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 VAS_EBOOT. If not, see <http://www.gnu.org/licenses/>.
*/
#include <VasEBoot/err.h>
#include <VasEBoot/file.h>
#include <VasEBoot/mm.h>
#include <VasEBoot/misc.h>
#include <VasEBoot/disk.h>
#include <VasEBoot/dl.h>
#include <VasEBoot/types.h>
#include <VasEBoot/fshelp.h>
#include <VasEBoot/charset.h>
#include <VasEBoot/lockdown.h>
VAS_EBOOT_MOD_LICENSE ("GPLv3+");
/* The affs bootblock. */
struct VasEBoot_affs_bblock
{
VasEBoot_uint8_t type[3];
VasEBoot_uint8_t flags;
VasEBoot_uint32_t checksum;
VasEBoot_uint32_t rootblock;
} VAS_EBOOT_PACKED;
/* Set if the filesystem is a AFFS filesystem. Otherwise this is an
OFS filesystem. */
#define VAS_EBOOT_AFFS_FLAG_FFS 1
/* The affs rootblock. */
struct VasEBoot_affs_rblock
{
VasEBoot_uint32_t type;
VasEBoot_uint8_t unused1[8];
VasEBoot_uint32_t htsize;
VasEBoot_uint32_t unused2;
VasEBoot_uint32_t checksum;
VasEBoot_uint32_t hashtable[1];
} VAS_EBOOT_PACKED;
struct VasEBoot_affs_time
{
VasEBoot_int32_t day;
VasEBoot_uint32_t min;
VasEBoot_uint32_t hz;
} VAS_EBOOT_PACKED;
/* The second part of a file header block. */
struct VasEBoot_affs_file
{
VasEBoot_uint8_t unused1[12];
VasEBoot_uint32_t size;
VasEBoot_uint8_t unused2[92];
struct VasEBoot_affs_time mtime;
VasEBoot_uint8_t namelen;
VasEBoot_uint8_t name[30];
VasEBoot_uint8_t unused3[5];
VasEBoot_uint32_t hardlink;
VasEBoot_uint32_t unused4[6];
VasEBoot_uint32_t next;
VasEBoot_uint32_t parent;
VasEBoot_uint32_t extension;
VasEBoot_uint32_t type;
} VAS_EBOOT_PACKED;
/* The location of `struct VasEBoot_affs_file' relative to the end of a
file header block. */
#define VAS_EBOOT_AFFS_FILE_LOCATION 200
/* The offset in both the rootblock and the file header block for the
hashtable, symlink and block pointers (all synonyms). */
#define VAS_EBOOT_AFFS_HASHTABLE_OFFSET 24
#define VAS_EBOOT_AFFS_BLOCKPTR_OFFSET 24
#define VAS_EBOOT_AFFS_SYMLINK_OFFSET 24
enum
{
VAS_EBOOT_AFFS_FILETYPE_DIR = 2,
VAS_EBOOT_AFFS_FILETYPE_SYMLINK = 3,
VAS_EBOOT_AFFS_FILETYPE_HARDLINK = 0xfffffffc,
VAS_EBOOT_AFFS_FILETYPE_REG = 0xfffffffd
};
#define AFFS_MAX_LOG_BLOCK_SIZE 4
#define AFFS_MAX_SUPERBLOCK 1
struct VasEBoot_fshelp_node
{
struct VasEBoot_affs_data *data;
VasEBoot_uint32_t block;
struct VasEBoot_fshelp_node *parent;
struct VasEBoot_affs_file di;
VasEBoot_uint32_t *block_cache;
VasEBoot_uint32_t last_block_cache;
};
/* Information about a "mounted" affs filesystem. */
struct VasEBoot_affs_data
{
struct VasEBoot_affs_bblock bblock;
struct VasEBoot_fshelp_node diropen;
VasEBoot_disk_t disk;
/* Log blocksize in sectors. */
int log_blocksize;
/* The number of entries in the hashtable. */
unsigned int htsize;
};
static VasEBoot_dl_t my_mod;
static VasEBoot_disk_addr_t
VasEBoot_affs_read_block (VasEBoot_fshelp_node_t node, VasEBoot_disk_addr_t fileblock)
{
VasEBoot_uint32_t target, curblock;
VasEBoot_uint32_t pos;
struct VasEBoot_affs_file file;
struct VasEBoot_affs_data *data = node->data;
VasEBoot_uint64_t mod;
if (!node->block_cache)
{
node->block_cache = VasEBoot_malloc (((VasEBoot_be_to_cpu32 (node->di.size)
>> (9 + node->data->log_blocksize))
/ data->htsize + 2)
* sizeof (node->block_cache[0]));
if (!node->block_cache)
return -1;
node->last_block_cache = 0;
node->block_cache[0] = node->block;
}
/* Files are at most 2G on AFFS, so no need for 64-bit division. */
target = (VasEBoot_uint32_t) fileblock / data->htsize;
mod = (VasEBoot_uint32_t) fileblock % data->htsize;
/* Find the block that points to the fileblock we are looking up by
following the chain until the right table is reached. */
for (curblock = node->last_block_cache + 1; curblock < target + 1; curblock++)
{
VasEBoot_disk_read (data->disk,
(((VasEBoot_uint64_t) node->block_cache[curblock - 1] + 1)
<< data->log_blocksize) - 1,
VAS_EBOOT_DISK_SECTOR_SIZE - VAS_EBOOT_AFFS_FILE_LOCATION,
sizeof (file), &file);
if (VasEBoot_errno)
return 0;
node->block_cache[curblock] = VasEBoot_be_to_cpu32 (file.extension);
node->last_block_cache = curblock;
}
/* Translate the fileblock to the block within the right table. */
VasEBoot_disk_read (data->disk, (VasEBoot_uint64_t) node->block_cache[target]
<< data->log_blocksize,
VAS_EBOOT_AFFS_BLOCKPTR_OFFSET
+ (data->htsize - mod - 1) * sizeof (pos),
sizeof (pos), &pos);
if (VasEBoot_errno)
return 0;
return VasEBoot_be_to_cpu32 (pos);
}
static struct VasEBoot_affs_data *
VasEBoot_affs_mount (VasEBoot_disk_t disk)
{
struct VasEBoot_affs_data *data;
VasEBoot_uint32_t *rootblock = 0;
struct VasEBoot_affs_rblock *rblock = 0;
int log_blocksize = 0;
int bsnum = 0;
data = VasEBoot_zalloc (sizeof (struct VasEBoot_affs_data));
if (!data)
return 0;
for (bsnum = 0; bsnum < AFFS_MAX_SUPERBLOCK + 1; bsnum++)
{
/* Read the bootblock. */
VasEBoot_disk_read (disk, bsnum, 0, sizeof (struct VasEBoot_affs_bblock),
&data->bblock);
if (VasEBoot_errno)
goto fail;
/* Make sure this is an affs filesystem. */
if (VasEBoot_strncmp ((char *) (data->bblock.type), "DOS", 3) != 0
/* Test if the filesystem is a OFS filesystem. */
|| !(data->bblock.flags & VAS_EBOOT_AFFS_FLAG_FFS))
continue;
/* No sane person uses more than 8KB for a block. At least I hope
for that person because in that case this won't work. */
if (!rootblock)
rootblock = VasEBoot_malloc (VAS_EBOOT_DISK_SECTOR_SIZE
<< AFFS_MAX_LOG_BLOCK_SIZE);
if (!rootblock)
goto fail;
rblock = (struct VasEBoot_affs_rblock *) rootblock;
/* The filesystem blocksize is not stored anywhere in the filesystem
itself. One way to determine it is try reading blocks for the
rootblock until the checksum is correct. */
for (log_blocksize = 0; log_blocksize <= AFFS_MAX_LOG_BLOCK_SIZE;
log_blocksize++)
{
VasEBoot_uint32_t *currblock = rootblock;
unsigned int i;
VasEBoot_uint32_t checksum = 0;
/* Read the rootblock. */
VasEBoot_disk_read (disk,
(VasEBoot_uint64_t) VasEBoot_be_to_cpu32 (data->bblock.rootblock)
<< log_blocksize, 0,
VAS_EBOOT_DISK_SECTOR_SIZE << log_blocksize, rootblock);
if (VasEBoot_errno == VAS_EBOOT_ERR_OUT_OF_RANGE)
{
VasEBoot_errno = 0;
break;
}
if (VasEBoot_errno)
goto fail;
if (rblock->type != VasEBoot_cpu_to_be32_compile_time (2)
|| rblock->htsize == 0
|| currblock[(VAS_EBOOT_DISK_SECTOR_SIZE << log_blocksize)
/ sizeof (*currblock) - 1]
!= VasEBoot_cpu_to_be32_compile_time (1))
continue;
for (i = 0; i < (VAS_EBOOT_DISK_SECTOR_SIZE << log_blocksize)
/ sizeof (*currblock);
i++)
checksum += VasEBoot_be_to_cpu32 (currblock[i]);
if (checksum == 0)
{
data->log_blocksize = log_blocksize;
data->disk = disk;
data->htsize = VasEBoot_be_to_cpu32 (rblock->htsize);
data->diropen.data = data;
data->diropen.block = VasEBoot_be_to_cpu32 (data->bblock.rootblock);
data->diropen.parent = NULL;
VasEBoot_memcpy (&data->diropen.di, rootblock,
sizeof (data->diropen.di));
VasEBoot_free (rootblock);
return data;
}
}
}
fail:
if (VasEBoot_errno == VAS_EBOOT_ERR_NONE || VasEBoot_errno == VAS_EBOOT_ERR_OUT_OF_RANGE)
VasEBoot_error (VAS_EBOOT_ERR_BAD_FS, "not an AFFS filesystem");
VasEBoot_free (data);
VasEBoot_free (rootblock);
return 0;
}
static char *
VasEBoot_affs_read_symlink (VasEBoot_fshelp_node_t node)
{
struct VasEBoot_affs_data *data = node->data;
VasEBoot_uint8_t *latin1, *utf8;
const VasEBoot_size_t symlink_size = ((VAS_EBOOT_DISK_SECTOR_SIZE
<< data->log_blocksize) - VAS_EBOOT_AFFS_SYMLINK_OFFSET);
latin1 = VasEBoot_malloc (symlink_size + 1);
if (!latin1)
return 0;
VasEBoot_disk_read (data->disk,
(VasEBoot_uint64_t) node->block << data->log_blocksize,
VAS_EBOOT_AFFS_SYMLINK_OFFSET,
symlink_size, latin1);
if (VasEBoot_errno)
{
VasEBoot_free (latin1);
return 0;
}
latin1[symlink_size] = 0;
utf8 = VasEBoot_calloc (VAS_EBOOT_MAX_UTF8_PER_LATIN1 + 1, symlink_size);
if (!utf8)
{
VasEBoot_free (latin1);
return 0;
}
*VasEBoot_latin1_to_utf8 (utf8, latin1, symlink_size) = '\0';
VasEBoot_dprintf ("affs", "Symlink: `%s'\n", utf8);
VasEBoot_free (latin1);
if (utf8[0] == ':')
utf8[0] = '/';
return (char *) utf8;
}
/* Helper for VasEBoot_affs_iterate_dir. */
static int
VasEBoot_affs_create_node (VasEBoot_fshelp_node_t dir,
VasEBoot_fshelp_iterate_dir_hook_t hook, void *hook_data,
struct VasEBoot_fshelp_node **node,
VasEBoot_uint32_t block, const struct VasEBoot_affs_file *fil)
{
struct VasEBoot_affs_data *data = dir->data;
int type = VAS_EBOOT_FSHELP_REG;
VasEBoot_uint8_t name_u8[sizeof (fil->name) * VAS_EBOOT_MAX_UTF8_PER_LATIN1 + 1];
VasEBoot_size_t len;
unsigned int nest;
*node = VasEBoot_zalloc (sizeof (**node));
if (!*node)
return 1;
(*node)->data = data;
(*node)->block = block;
(*node)->parent = dir;
len = fil->namelen;
if (len > sizeof (fil->name))
len = sizeof (fil->name);
*VasEBoot_latin1_to_utf8 (name_u8, fil->name, len) = '\0';
(*node)->di = *fil;
for (nest = 0; nest < 8; nest++)
{
switch ((*node)->di.type)
{
case VasEBoot_cpu_to_be32_compile_time (VAS_EBOOT_AFFS_FILETYPE_REG):
type = VAS_EBOOT_FSHELP_REG;
break;
case VasEBoot_cpu_to_be32_compile_time (VAS_EBOOT_AFFS_FILETYPE_DIR):
type = VAS_EBOOT_FSHELP_DIR;
break;
case VasEBoot_cpu_to_be32_compile_time (VAS_EBOOT_AFFS_FILETYPE_SYMLINK):
type = VAS_EBOOT_FSHELP_SYMLINK;
break;
case VasEBoot_cpu_to_be32_compile_time (VAS_EBOOT_AFFS_FILETYPE_HARDLINK):
{
VasEBoot_err_t err;
(*node)->block = VasEBoot_be_to_cpu32 ((*node)->di.hardlink);
err = VasEBoot_disk_read (data->disk,
(((VasEBoot_uint64_t) (*node)->block + 1) << data->log_blocksize)
- 1,
VAS_EBOOT_DISK_SECTOR_SIZE - VAS_EBOOT_AFFS_FILE_LOCATION,
sizeof ((*node)->di), (char *) &(*node)->di);
if (err)
{
VasEBoot_free (*node);
return 1;
}
continue;
}
default:
{
VasEBoot_free (*node);
return 0;
}
}
break;
}
if (nest == 8)
{
VasEBoot_free (*node);
return 0;
}
type |= VAS_EBOOT_FSHELP_CASE_INSENSITIVE;
if (hook ((char *) name_u8, type, *node, hook_data))
{
*node = 0;
return 1;
}
*node = 0;
return 0;
}
static int
VasEBoot_affs_iterate_dir (VasEBoot_fshelp_node_t dir,
VasEBoot_fshelp_iterate_dir_hook_t hook, void *hook_data)
{
unsigned int i;
struct VasEBoot_affs_file file;
struct VasEBoot_fshelp_node *node, *orig_node;
struct VasEBoot_affs_data *data = dir->data;
VasEBoot_uint32_t *hashtable;
/* Create the directory entries for `.' and `..'. */
node = orig_node = VasEBoot_zalloc (sizeof (*node));
if (!node)
return 1;
*node = *dir;
if (hook (".", VAS_EBOOT_FSHELP_DIR, node, hook_data))
return 1;
if (dir->parent)
{
*node = *dir->parent;
if (hook ("..", VAS_EBOOT_FSHELP_DIR, node, hook_data))
return 1;
}
hashtable = VasEBoot_calloc (data->htsize, sizeof (*hashtable));
if (!hashtable)
return 1;
VasEBoot_disk_read (data->disk,
(VasEBoot_uint64_t) dir->block << data->log_blocksize,
VAS_EBOOT_AFFS_HASHTABLE_OFFSET,
data->htsize * sizeof (*hashtable), (char *) hashtable);
if (VasEBoot_errno)
goto fail;
for (i = 0; i < data->htsize; i++)
{
VasEBoot_uint32_t next;
if (!hashtable[i])
continue;
/* Every entry in the hashtable can be chained. Read the entire
chain. */
next = VasEBoot_be_to_cpu32 (hashtable[i]);
while (next)
{
VasEBoot_disk_read (data->disk,
(((VasEBoot_uint64_t) next + 1) << data->log_blocksize)
- 1,
VAS_EBOOT_DISK_SECTOR_SIZE - VAS_EBOOT_AFFS_FILE_LOCATION,
sizeof (file), (char *) &file);
if (VasEBoot_errno)
goto fail;
if (VasEBoot_affs_create_node (dir, hook, hook_data, &node, next, &file))
{
/* Node has been replaced in function. */
VasEBoot_free (orig_node);
VasEBoot_free (hashtable);
return 1;
}
next = VasEBoot_be_to_cpu32 (file.next);
}
}
fail:
VasEBoot_free (orig_node);
VasEBoot_free (hashtable);
return 0;
}
/* Open a file named NAME and initialize FILE. */
static VasEBoot_err_t
VasEBoot_affs_open (struct VasEBoot_file *file, const char *name)
{
struct VasEBoot_affs_data *data;
struct VasEBoot_fshelp_node *fdiro = 0;
VasEBoot_dl_ref (my_mod);
data = VasEBoot_affs_mount (file->device->disk);
if (!data)
goto fail;
VasEBoot_fshelp_find_file (name, &data->diropen, &fdiro, VasEBoot_affs_iterate_dir,
VasEBoot_affs_read_symlink, VAS_EBOOT_FSHELP_REG);
if (VasEBoot_errno)
goto fail;
file->size = VasEBoot_be_to_cpu32 (fdiro->di.size);
data->diropen = *fdiro;
VasEBoot_free (fdiro);
file->data = data;
file->offset = 0;
return 0;
fail:
if (data && fdiro != &data->diropen)
VasEBoot_free (fdiro);
VasEBoot_free (data);
VasEBoot_dl_unref (my_mod);
return VasEBoot_errno;
}
static VasEBoot_err_t
VasEBoot_affs_close (VasEBoot_file_t file)
{
struct VasEBoot_affs_data *data =
(struct VasEBoot_affs_data *) file->data;
VasEBoot_free (data->diropen.block_cache);
VasEBoot_free (file->data);
VasEBoot_dl_unref (my_mod);
return VAS_EBOOT_ERR_NONE;
}
/* Read LEN bytes data from FILE into BUF. */
static VasEBoot_ssize_t
VasEBoot_affs_read (VasEBoot_file_t file, char *buf, VasEBoot_size_t len)
{
struct VasEBoot_affs_data *data =
(struct VasEBoot_affs_data *) file->data;
return VasEBoot_fshelp_read_file (data->diropen.data->disk, &data->diropen,
file->read_hook, file->read_hook_data,
file->offset, len, buf, VasEBoot_affs_read_block,
VasEBoot_be_to_cpu32 (data->diropen.di.size),
data->log_blocksize, 0);
}
static VasEBoot_int32_t
aftime2ctime (const struct VasEBoot_affs_time *t)
{
return VasEBoot_be_to_cpu32 (t->day) * 86400
+ VasEBoot_be_to_cpu32 (t->min) * 60
+ VasEBoot_be_to_cpu32 (t->hz) / 50
+ 8 * 365 * 86400 + 86400 * 2;
}
/* Context for VasEBoot_affs_dir. */
struct VasEBoot_affs_dir_ctx
{
VasEBoot_fs_dir_hook_t hook;
void *hook_data;
};
/* Helper for VasEBoot_affs_dir. */
static int
VasEBoot_affs_dir_iter (const char *filename, enum VasEBoot_fshelp_filetype filetype,
VasEBoot_fshelp_node_t node, void *data)
{
struct VasEBoot_affs_dir_ctx *ctx = data;
struct VasEBoot_dirhook_info info;
VasEBoot_memset (&info, 0, sizeof (info));
info.dir = ((filetype & VAS_EBOOT_FSHELP_TYPE_MASK) == VAS_EBOOT_FSHELP_DIR);
info.mtimeset = 1;
info.mtime = aftime2ctime (&node->di.mtime);
VasEBoot_free (node);
return ctx->hook (filename, &info, ctx->hook_data);
}
static VasEBoot_err_t
VasEBoot_affs_dir (VasEBoot_device_t device, const char *path,
VasEBoot_fs_dir_hook_t hook, void *hook_data)
{
struct VasEBoot_affs_dir_ctx ctx = { hook, hook_data };
struct VasEBoot_affs_data *data = 0;
struct VasEBoot_fshelp_node *fdiro = 0;
VasEBoot_dl_ref (my_mod);
data = VasEBoot_affs_mount (device->disk);
if (!data)
goto fail;
VasEBoot_fshelp_find_file (path, &data->diropen, &fdiro, VasEBoot_affs_iterate_dir,
VasEBoot_affs_read_symlink, VAS_EBOOT_FSHELP_DIR);
if (VasEBoot_errno)
goto fail;
VasEBoot_affs_iterate_dir (fdiro, VasEBoot_affs_dir_iter, &ctx);
fail:
if (data && fdiro != &data->diropen)
VasEBoot_free (fdiro);
VasEBoot_free (data);
VasEBoot_dl_unref (my_mod);
return VasEBoot_errno;
}
static VasEBoot_err_t
VasEBoot_affs_label (VasEBoot_device_t device, char **label)
{
struct VasEBoot_affs_data *data;
struct VasEBoot_affs_file file;
VasEBoot_disk_t disk = device->disk;
VasEBoot_dl_ref (my_mod);
data = VasEBoot_affs_mount (disk);
if (data)
{
VasEBoot_size_t len;
/* The rootblock maps quite well on a file header block, it's
something we can use here. */
VasEBoot_disk_read (data->disk,
(((VasEBoot_uint64_t)
VasEBoot_be_to_cpu32 (data->bblock.rootblock) + 1)
<< data->log_blocksize) - 1,
VAS_EBOOT_DISK_SECTOR_SIZE - VAS_EBOOT_AFFS_FILE_LOCATION,
sizeof (file), &file);
if (VasEBoot_errno)
return VasEBoot_errno;
len = file.namelen;
if (len > sizeof (file.name))
len = sizeof (file.name);
*label = VasEBoot_calloc (VAS_EBOOT_MAX_UTF8_PER_LATIN1 + 1, len);
if (*label)
*VasEBoot_latin1_to_utf8 ((VasEBoot_uint8_t *) *label, file.name, len) = '\0';
}
else
*label = 0;
VasEBoot_dl_unref (my_mod);
VasEBoot_free (data);
return VasEBoot_errno;
}
static VasEBoot_err_t
VasEBoot_affs_mtime (VasEBoot_device_t device, VasEBoot_int64_t *t)
{
struct VasEBoot_affs_data *data;
VasEBoot_disk_t disk = device->disk;
struct VasEBoot_affs_time af_time;
*t = 0;
VasEBoot_dl_ref (my_mod);
data = VasEBoot_affs_mount (disk);
if (!data)
{
VasEBoot_dl_unref (my_mod);
return VasEBoot_errno;
}
VasEBoot_disk_read (data->disk,
(((VasEBoot_uint64_t)
VasEBoot_be_to_cpu32 (data->bblock.rootblock) + 1)
<< data->log_blocksize) - 1,
VAS_EBOOT_DISK_SECTOR_SIZE - 40,
sizeof (af_time), &af_time);
if (VasEBoot_errno)
{
VasEBoot_dl_unref (my_mod);
VasEBoot_free (data);
return VasEBoot_errno;
}
*t = aftime2ctime (&af_time);
VasEBoot_dl_unref (my_mod);
VasEBoot_free (data);
return VAS_EBOOT_ERR_NONE;
}
static struct VasEBoot_fs VasEBoot_affs_fs =
{
.name = "affs",
.fs_dir = VasEBoot_affs_dir,
.fs_open = VasEBoot_affs_open,
.fs_read = VasEBoot_affs_read,
.fs_close = VasEBoot_affs_close,
.fs_label = VasEBoot_affs_label,
.fs_mtime = VasEBoot_affs_mtime,
#ifdef VAS_EBOOT_UTIL
.reserved_first_sector = 0,
.blocklist_install = 1,
#endif
.next = 0
};
VAS_EBOOT_MOD_INIT(affs)
{
if (!VasEBoot_is_lockdown ())
{
VasEBoot_affs_fs.mod = mod;
VasEBoot_fs_register (&VasEBoot_affs_fs);
}
my_mod = mod;
}
VAS_EBOOT_MOD_FINI(affs)
{
if (!VasEBoot_is_lockdown ())
VasEBoot_fs_unregister (&VasEBoot_affs_fs);
}