/* jfs.c - JFS. */ /* * GRUB -- GRand Unified Bootloader * Copyright (C) 2004, 2005 Free Software Foundation, Inc. * * This program 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 2 of the License, or * (at your option) any later version. * * This program 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 this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #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 { struct grub_jfs_treehead tree; struct grub_jfs_tree_extent extents[16]; } file __attribute__ ((packed)); 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)); #ifndef GRUB_UTIL static grub_dl_t my_mod; #endif 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), (char *) &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), (char *) 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), (char *) &data->sblock)) goto fail; if (grub_strncmp (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), (char *) &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_malloc (sizeof (struct grub_jfs_diropen)); if (!diro) return 0; diro->index = 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 = inode->dir.header.sorted; diro->count = inode->dir.header.count; diro->dirpage = 0; 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 entrie 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 (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 (*read_hook) (unsigned long sector, unsigned offset, unsigned length), int pos, unsigned int 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 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++; } 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, 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, int dir)) { struct grub_jfs_data *data = 0; struct grub_jfs_diropen *diro = 0; #ifndef GRUB_UTIL grub_dl_ref (my_mod); #endif 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; int isdir; if (grub_jfs_read_inode (data, diro->ino, &inode)) goto fail; isdir = (grub_le_to_cpu32 (inode.mode) & GRUB_JFS_FILETYPE_MASK) == GRUB_JFS_FILETYPE_DIR; if (hook (diro->name, isdir)) 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); #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif 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; #ifndef GRUB_UTIL grub_dl_ref (my_mod); #endif 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: #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif grub_free (data); return grub_errno;; } static grub_ssize_t grub_jfs_read (grub_file_t file, char *buf, grub_ssize_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); #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif 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 (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); #ifndef GRUB_UTIL my_mod = mod; #endif } GRUB_MOD_FINI(jfs) { grub_fs_unregister (&grub_jfs_fs); }