/* jfs.c - JFS. */
/*
* 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 .
*/
#include
#include
#include
#include
#include
#include
#include
#define GRUB_JFS_MAX_SYMLNK_CNT 8
#define GRUB_JFS_FILETYPE_MASK 0170000
#define GRUB_JFS_FILETYPE_REG 0100000
#define GRUB_JFS_FILETYPE_LNK 0120000
#define GRUB_JFS_FILETYPE_DIR 0040000
#define GRUB_JFS_SBLOCK 64
#define GRUB_JFS_AGGR_INODE 2
#define GRUB_JFS_FS1_INODE_BLK 104
#define GRUB_JFS_TREE_LEAF 2
struct grub_jfs_sblock
{
/* The magic for JFS. It should contain the string "JFS1". */
grub_uint8_t magic[4];
grub_uint32_t version;
grub_uint64_t ag_size;
/* The size of a filesystem block in bytes. XXX: currently only
4096 was tested. */
grub_uint32_t blksz;
grub_uint16_t log2_blksz;
grub_uint8_t unused[71];
grub_uint8_t volname[11];
};
struct grub_jfs_extent
{
/* The length of the extent in filesystem blocks. */
grub_uint16_t length;
grub_uint8_t length2;
/* The physical offset of the first block on the disk. */
grub_uint8_t blk1;
grub_uint32_t blk2;
} __attribute__ ((packed));
struct grub_jfs_iag
{
grub_uint8_t unused[3072];
struct grub_jfs_extent inodes[128];
} __attribute__ ((packed));
/* The head of the tree used to find extents. */
struct grub_jfs_treehead
{
grub_uint64_t next;
grub_uint64_t prev;
grub_uint8_t flags;
grub_uint8_t unused;
grub_uint16_t count;
grub_uint16_t max;
grub_uint8_t unused2[10];
} __attribute__ ((packed));
/* A node in the extent tree. */
struct grub_jfs_tree_extent
{
grub_uint8_t flags;
grub_uint16_t unused;
/* The offset is the key used to lookup an extent. */
grub_uint8_t offset1;
grub_uint32_t offset2;
struct grub_jfs_extent extent;
} __attribute__ ((packed));
/* The tree of directory entries. */
struct grub_jfs_tree_dir
{
/* Pointers to the previous and next tree headers of other nodes on
this level. */
grub_uint64_t nextb;
grub_uint64_t prevb;
grub_uint8_t flags;
/* The amount of dirents in this node. */
grub_uint8_t count;
grub_uint8_t freecnt;
grub_uint8_t freelist;
grub_uint8_t maxslot;
/* The location of the sorted array of pointers to dirents. */
grub_uint8_t sindex;
grub_uint8_t unused[10];
} __attribute__ ((packed));
/* An internal node in the dirents tree. */
struct grub_jfs_internal_dirent
{
struct grub_jfs_extent ex;
grub_uint8_t next;
grub_uint8_t len;
grub_uint16_t namepart[11];
} __attribute__ ((packed));
/* A leaf node in the dirents tree. */
struct grub_jfs_leaf_dirent
{
/* The inode for this dirent. */
grub_uint32_t inode;
grub_uint8_t next;
/* The size of the name. */
grub_uint8_t len;
grub_uint16_t namepart[11];
grub_uint32_t index;
} __attribute__ ((packed));
/* A leaf in the dirents tree. This one is used if the previously
dirent was not big enough to store the name. */
struct grub_jfs_leaf_next_dirent
{
grub_uint8_t next;
grub_uint8_t len;
grub_uint16_t namepart[15];
} __attribute__ ((packed));
struct grub_jfs_inode
{
grub_uint32_t stamp;
grub_uint32_t fileset;
grub_uint32_t inode;
grub_uint8_t unused[12];
grub_uint64_t size;
grub_uint8_t unused2[20];
grub_uint32_t mode;
grub_uint8_t unused3[72];
grub_uint8_t unused4[96];
union
{
/* The tree describing the extents of the file. */
struct __attribute__ ((packed))
{
struct grub_jfs_treehead tree;
struct grub_jfs_tree_extent extents[16];
} file;
union
{
/* The tree describing the dirents. */
struct
{
grub_uint8_t unused[16];
grub_uint8_t flags;
/* Amount of dirents in this node. */
grub_uint8_t count;
grub_uint8_t freecnt;
grub_uint8_t freelist;
grub_uint32_t idotdot;
grub_uint8_t sorted[8];
} header;
struct grub_jfs_leaf_dirent dirents[8];
} dir __attribute__ ((packed));
/* Fast symlink. */
struct
{
grub_uint8_t unused[32];
grub_uint8_t path[128];
} symlink;
} __attribute__ ((packed));
} __attribute__ ((packed));
struct grub_jfs_data
{
struct grub_jfs_sblock sblock;
grub_disk_t disk;
struct grub_jfs_inode fileset;
struct grub_jfs_inode currinode;
int pos;
int linknest;
} __attribute__ ((packed));
struct grub_jfs_diropen
{
int index;
union
{
struct grub_jfs_tree_dir header;
struct grub_jfs_leaf_dirent dirent[0];
struct grub_jfs_leaf_next_dirent next_dirent[0];
char sorted[0];
} *dirpage __attribute__ ((packed));
struct grub_jfs_data *data;
struct grub_jfs_inode *inode;
int count;
char *sorted;
struct grub_jfs_leaf_dirent *leaf;
struct grub_jfs_leaf_next_dirent *next_leaf;
/* The filename and inode of the last read dirent. */
char name[255];
grub_uint32_t ino;
} __attribute__ ((packed));
static grub_dl_t my_mod;
static grub_err_t grub_jfs_lookup_symlink (struct grub_jfs_data *data, int ino);
/* Get the block number for the block BLK in the node INODE in the
mounted filesystem DATA. */
static int
grub_jfs_blkno (struct grub_jfs_data *data, struct grub_jfs_inode *inode,
unsigned int blk)
{
auto int getblk (struct grub_jfs_treehead *treehead,
struct grub_jfs_tree_extent *extents);
int getblk (struct grub_jfs_treehead *treehead,
struct grub_jfs_tree_extent *extents)
{
int found = -1;
int i;
for (i = 0; i < grub_le_to_cpu16 (treehead->count) - 2; i++)
{
if (treehead->flags & GRUB_JFS_TREE_LEAF)
{
/* Read the leafnode. */
if (grub_le_to_cpu32 (extents[i].offset2) <= blk
&& ((grub_le_to_cpu16 (extents[i].extent.length))
+ (extents[i].extent.length2 << 8)
+ grub_le_to_cpu32 (extents[i].offset2)) > blk)
return (blk - grub_le_to_cpu32 (extents[i].offset2)
+ grub_le_to_cpu32 (extents[i].extent.blk2));
}
else
if (blk >= grub_le_to_cpu32 (extents[i].offset2))
found = i;
}
if (found != -1)
{
struct
{
struct grub_jfs_treehead treehead;
struct grub_jfs_tree_extent extents[254];
} tree;
if (grub_disk_read (data->disk,
grub_le_to_cpu32 (extents[found].extent.blk2)
<< (grub_le_to_cpu16 (data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS), 0,
sizeof (tree), (char *) &tree))
return -1;
return getblk (&tree.treehead, &tree.extents[0]);
}
return -1;
}
return getblk (&inode->file.tree, &inode->file.extents[0]);
}
static grub_err_t
grub_jfs_read_inode (struct grub_jfs_data *data, int ino,
struct grub_jfs_inode *inode)
{
struct grub_jfs_iag iag;
int iagnum = ino / 4096;
int inoext = (ino % 4096) / 32;
int inonum = (ino % 4096) % 32;
grub_uint32_t iagblk;
grub_uint32_t inoblk;
iagblk = grub_jfs_blkno (data, &data->fileset, iagnum + 1);
if (grub_errno)
return grub_errno;
/* Read in the IAG. */
if (grub_disk_read (data->disk,
iagblk << (grub_le_to_cpu16 (data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS), 0,
sizeof (struct grub_jfs_iag), &iag))
return grub_errno;
inoblk = grub_le_to_cpu32 (iag.inodes[inoext].blk2);
inoblk <<= (grub_le_to_cpu16 (data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS);
inoblk += inonum;
if (grub_disk_read (data->disk, inoblk, 0,
sizeof (struct grub_jfs_inode), inode))
return grub_errno;
return 0;
}
static struct grub_jfs_data *
grub_jfs_mount (grub_disk_t disk)
{
struct grub_jfs_data *data = 0;
data = grub_malloc (sizeof (struct grub_jfs_data));
if (!data)
return 0;
/* Read the superblock. */
if (grub_disk_read (disk, GRUB_JFS_SBLOCK, 0,
sizeof (struct grub_jfs_sblock), &data->sblock))
goto fail;
if (grub_strncmp ((char *) (data->sblock.magic), "JFS1", 4))
{
grub_error (GRUB_ERR_BAD_FS, "not a jfs filesystem");
goto fail;
}
data->disk = disk;
data->pos = 0;
data->linknest = 0;
/* Read the inode of the first fileset. */
if (grub_disk_read (data->disk, GRUB_JFS_FS1_INODE_BLK, 0,
sizeof (struct grub_jfs_inode), &data->fileset))
goto fail;
return data;
fail:
grub_free (data);
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
grub_error (GRUB_ERR_BAD_FS, "not a jfs filesystem");
return 0;
}
static struct grub_jfs_diropen *
grub_jfs_opendir (struct grub_jfs_data *data, struct grub_jfs_inode *inode)
{
struct grub_jfs_internal_dirent *de;
struct grub_jfs_diropen *diro;
int blk;
de = (struct grub_jfs_internal_dirent *) inode->dir.dirents;
if (!((grub_le_to_cpu32 (inode->mode)
& GRUB_JFS_FILETYPE_MASK) == GRUB_JFS_FILETYPE_DIR))
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, "not a directory");
return 0;
}
diro = grub_zalloc (sizeof (struct grub_jfs_diropen));
if (!diro)
return 0;
diro->data = data;
diro->inode = inode;
/* Check if the entire tree is contained within the inode. */
if (inode->file.tree.flags & GRUB_JFS_TREE_LEAF)
{
diro->leaf = inode->dir.dirents;
diro->next_leaf = (struct grub_jfs_leaf_next_dirent *) de;
diro->sorted = (char *) (inode->dir.header.sorted);
diro->count = inode->dir.header.count;
return diro;
}
diro->dirpage = grub_malloc (grub_le_to_cpu32 (data->sblock.blksz));
if (!diro->dirpage)
{
grub_free (diro);
return 0;
}
blk = grub_le_to_cpu32 (de[inode->dir.header.sorted[0]].ex.blk2);
blk <<= (grub_le_to_cpu16 (data->sblock.log2_blksz) - GRUB_DISK_SECTOR_BITS);
/* Read in the nodes until we are on the leaf node level. */
do
{
int index;
if (grub_disk_read (data->disk, blk, 0,
grub_le_to_cpu32 (data->sblock.blksz),
diro->dirpage->sorted))
{
grub_free (diro->dirpage);
grub_free (diro);
return 0;
}
de = (struct grub_jfs_internal_dirent *) diro->dirpage->dirent;
index = diro->dirpage->sorted[diro->dirpage->header.sindex * 32];
blk = (grub_le_to_cpu32 (de[index].ex.blk2)
<< (grub_le_to_cpu16 (data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS));
} while (!(diro->dirpage->header.flags & GRUB_JFS_TREE_LEAF));
diro->leaf = diro->dirpage->dirent;
diro->next_leaf = diro->dirpage->next_dirent;
diro->sorted = &diro->dirpage->sorted[diro->dirpage->header.sindex * 32];
diro->count = diro->dirpage->header.count;
return diro;
}
static void
grub_jfs_closedir (struct grub_jfs_diropen *diro)
{
if (!diro)
return;
grub_free (diro->dirpage);
grub_free (diro);
}
/* Read in the next dirent from the directory described by DIRO. */
static grub_err_t
grub_jfs_getent (struct grub_jfs_diropen *diro)
{
int strpos = 0;
struct grub_jfs_leaf_dirent *leaf;
struct grub_jfs_leaf_next_dirent *next_leaf;
int len;
int nextent;
grub_uint16_t filename[255];
auto void addstr (grub_uint16_t *uname, int ulen);
/* Add the unicode string to the utf16 filename buffer. */
void addstr (grub_uint16_t *name, int ulen)
{
while (ulen--)
filename[strpos++] = *(name++);
}
/* The last node, read in more. */
if (diro->index == diro->count)
{
unsigned int next;
/* If the inode contains the entry tree or if this was the last
node, there is nothing to read. */
if ((diro->inode->file.tree.flags & GRUB_JFS_TREE_LEAF)
|| !grub_le_to_cpu64 (diro->dirpage->header.nextb))
return GRUB_ERR_OUT_OF_RANGE;
next = grub_le_to_cpu64 (diro->dirpage->header.nextb);
next <<= (grub_le_to_cpu16 (diro->data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS);
if (grub_disk_read (diro->data->disk, next, 0,
grub_le_to_cpu32 (diro->data->sblock.blksz),
diro->dirpage->sorted))
return grub_errno;
diro->leaf = diro->dirpage->dirent;
diro->next_leaf = diro->dirpage->next_dirent;
diro->sorted = &diro->dirpage->sorted[diro->dirpage->header.sindex * 32];
diro->count = diro->dirpage->header.count;
diro->index = 0;
}
leaf = &diro->leaf[(int) diro->sorted[diro->index]];
next_leaf = &diro->next_leaf[diro->index];
len = leaf->len;
if (!len)
{
diro->index++;
return grub_jfs_getent (diro);
}
addstr (leaf->namepart, len < 11 ? len : 11);
diro->ino = grub_le_to_cpu32 (leaf->inode);
len -= 11;
/* Move down to the leaf level. */
nextent = leaf->next;
if (leaf->next != 255)
do
{
next_leaf = &diro->next_leaf[nextent];
addstr (next_leaf->namepart, len < 15 ? len : 15 );
len -= 15;
nextent = next_leaf->next;
} while (next_leaf->next != 255 && len > 0);
diro->index++;
/* Convert the temporary UTF16 filename to UTF8. */
*grub_utf16_to_utf8 ((grub_uint8_t *) (diro->name), filename, strpos) = '\0';
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_jfs_read_file (struct grub_jfs_data *data,
void NESTED_FUNC_ATTR (*read_hook) (grub_disk_addr_t sector,
unsigned offset, unsigned length),
int pos, grub_size_t len, char *buf)
{
int i;
int blockcnt;
/* Adjust len so it we can't read past the end of the file. */
if (len > data->currinode.size)
len = data->currinode.size;
blockcnt = ((len + pos + grub_le_to_cpu32 (data->sblock.blksz) - 1)
/ grub_le_to_cpu32 (data->sblock.blksz));
for (i = pos / grub_le_to_cpu32 (data->sblock.blksz); i < blockcnt; i++)
{
int blknr;
int blockoff = pos % grub_le_to_cpu32 (data->sblock.blksz);
int blockend = grub_le_to_cpu32 (data->sblock.blksz);
int skipfirst = 0;
blknr = grub_jfs_blkno (data, &data->currinode, i);
if (grub_errno)
return -1;
/* Last block. */
if (i == blockcnt - 1)
{
blockend = (len + pos) % grub_le_to_cpu32 (data->sblock.blksz);
if (!blockend)
blockend = grub_le_to_cpu32 (data->sblock.blksz);
}
/* First block. */
if (i == (pos / (int) grub_le_to_cpu32 (data->sblock.blksz)))
{
skipfirst = blockoff;
blockend -= skipfirst;
}
data->disk->read_hook = read_hook;
grub_disk_read (data->disk,
blknr << (grub_le_to_cpu16 (data->sblock.log2_blksz)
- GRUB_DISK_SECTOR_BITS),
skipfirst, blockend, buf);
data->disk->read_hook = 0;
if (grub_errno)
return -1;
buf += grub_le_to_cpu32 (data->sblock.blksz) - skipfirst;
}
return len;
}
/* Find the file with the pathname PATH on the filesystem described by
DATA. */
static grub_err_t
grub_jfs_find_file (struct grub_jfs_data *data, const char *path)
{
char fpath[grub_strlen (path)];
char *name = fpath;
char *next;
unsigned int pos = 0;
struct grub_jfs_diropen *diro;
grub_strncpy (fpath, path, grub_strlen (path) + 1);
if (grub_jfs_read_inode (data, GRUB_JFS_AGGR_INODE, &data->currinode))
return grub_errno;
/* Skip the first slashes. */
while (*name == '/')
{
name++;
if (!*name)
return 0;
}
/* Extract the actual part from the pathname. */
next = grub_strchr (name, '/');
if (next)
{
while (*next == '/')
{
next[0] = '\0';
next++;
}
}
diro = grub_jfs_opendir (data, &data->currinode);
if (!diro)
return grub_errno;
for (;;)
{
if (grub_strlen (name) == 0)
return GRUB_ERR_NONE;
if (grub_jfs_getent (diro) == GRUB_ERR_OUT_OF_RANGE)
break;
/* Check if the current direntry matches the current part of the
pathname. */
if (!grub_strcmp (name, diro->name))
{
int ino = diro->ino;
int dirino = grub_le_to_cpu32 (data->currinode.inode);
grub_jfs_closedir (diro);
diro = 0;
if (grub_jfs_read_inode (data, ino, &data->currinode))
break;
/* Check if this is a symlink. */
if ((grub_le_to_cpu32 (data->currinode.mode)
& GRUB_JFS_FILETYPE_MASK) == GRUB_JFS_FILETYPE_LNK)
{
grub_jfs_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++;
}
/* Open this directory for reading dirents. */
diro = grub_jfs_opendir (data, &data->currinode);
if (!diro)
return grub_errno;
continue;
}
}
grub_jfs_closedir (diro);
grub_error (GRUB_ERR_FILE_NOT_FOUND, "file not found");
return grub_errno;
}
static grub_err_t
grub_jfs_lookup_symlink (struct grub_jfs_data *data, int ino)
{
int size = grub_le_to_cpu64 (data->currinode.size);
char symlink[size + 1];
if (++data->linknest > GRUB_JFS_MAX_SYMLNK_CNT)
return grub_error (GRUB_ERR_SYMLINK_LOOP, "too deep nesting of symlinks");
if (size <= 128)
grub_strncpy (symlink, (char *) (data->currinode.symlink.path), 128);
else if (grub_jfs_read_file (data, 0, 0, size, symlink) < 0)
return grub_errno;
symlink[size] = '\0';
/* The symlink is an absolute path, go back to the root inode. */
if (symlink[0] == '/')
ino = 2;
/* Now load in the old inode. */
if (grub_jfs_read_inode (data, ino, &data->currinode))
return grub_errno;
grub_jfs_find_file (data, symlink);
if (grub_errno)
grub_error (grub_errno, "Can not follow symlink `%s'.", symlink);
return grub_errno;
}
static grub_err_t
grub_jfs_dir (grub_device_t device, const char *path,
int (*hook) (const char *filename,
const struct grub_dirhook_info *info))
{
struct grub_jfs_data *data = 0;
struct grub_jfs_diropen *diro = 0;
grub_dl_ref (my_mod);
data = grub_jfs_mount (device->disk);
if (!data)
goto fail;
if (grub_jfs_find_file (data, path))
goto fail;
diro = grub_jfs_opendir (data, &data->currinode);
if (!diro)
goto fail;
/* Iterate over the dirents in the directory that was found. */
while (grub_jfs_getent (diro) != GRUB_ERR_OUT_OF_RANGE)
{
struct grub_jfs_inode inode;
struct grub_dirhook_info info;
grub_memset (&info, 0, sizeof (info));
if (grub_jfs_read_inode (data, diro->ino, &inode))
goto fail;
info.dir = (grub_le_to_cpu32 (inode.mode)
& GRUB_JFS_FILETYPE_MASK) == GRUB_JFS_FILETYPE_DIR;
if (hook (diro->name, &info))
goto fail;
}
/* XXX: GRUB_ERR_OUT_OF_RANGE is used for the last dirent. */
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
grub_errno = 0;
fail:
grub_jfs_closedir (diro);
grub_free (data);
grub_dl_unref (my_mod);
return grub_errno;
}
/* Open a file named NAME and initialize FILE. */
static grub_err_t
grub_jfs_open (struct grub_file *file, const char *name)
{
struct grub_jfs_data *data;
grub_dl_ref (my_mod);
data = grub_jfs_mount (file->device->disk);
if (!data)
goto fail;
grub_jfs_find_file (data, name);
if (grub_errno)
goto fail;
/* It is only possible for open regular files. */
if (! ((grub_le_to_cpu32 (data->currinode.mode)
& GRUB_JFS_FILETYPE_MASK) == GRUB_JFS_FILETYPE_REG))
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, "not a regular file");
goto fail;
}
file->data = data;
file->size = grub_le_to_cpu64 (data->currinode.size);
return 0;
fail:
grub_dl_unref (my_mod);
grub_free (data);
return grub_errno;
}
static grub_ssize_t
grub_jfs_read (grub_file_t file, char *buf, grub_size_t len)
{
struct grub_jfs_data *data =
(struct grub_jfs_data *) file->data;
return grub_jfs_read_file (data, file->read_hook, file->offset, len, buf);
}
static grub_err_t
grub_jfs_close (grub_file_t file)
{
grub_free (file->data);
grub_dl_unref (my_mod);
return GRUB_ERR_NONE;
}
static grub_err_t
grub_jfs_label (grub_device_t device, char **label)
{
struct grub_jfs_data *data;
data = grub_jfs_mount (device->disk);
if (data)
*label = grub_strndup ((char *) (data->sblock.volname), 11);
else
*label = 0;
return grub_errno;
}
static struct grub_fs grub_jfs_fs =
{
.name = "jfs",
.dir = grub_jfs_dir,
.open = grub_jfs_open,
.read = grub_jfs_read,
.close = grub_jfs_close,
.label = grub_jfs_label,
.next = 0
};
GRUB_MOD_INIT(jfs)
{
grub_fs_register (&grub_jfs_fs);
my_mod = mod;
}
GRUB_MOD_FINI(jfs)
{
grub_fs_unregister (&grub_jfs_fs);
}