diff options
Diffstat (limited to 'grub-core/fs/sfs.c')
| -rw-r--r-- | grub-core/fs/sfs.c | 789 |
1 files changed, 789 insertions, 0 deletions
diff --git a/grub-core/fs/sfs.c b/grub-core/fs/sfs.c new file mode 100644 index 0000000..983e880 --- /dev/null +++ b/grub-core/fs/sfs.c @@ -0,0 +1,789 @@ +/* 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> +#include <grub/charset.h> +#include <grub/safemath.h> + +GRUB_MOD_LICENSE ("GPLv3+"); + +/* The common header for a block. */ +struct grub_sfs_bheader +{ + grub_uint8_t magic[4]; + grub_uint32_t chksum; + grub_uint32_t ipointtomyself; +} GRUB_PACKED; + +/* The sfs rootblock. */ +struct grub_sfs_rblock +{ + struct grub_sfs_bheader header; + grub_uint32_t version; + grub_uint32_t createtime; + grub_uint8_t flags; + grub_uint8_t unused1[31]; + grub_uint32_t blocksize; + grub_uint8_t unused2[40]; + grub_uint8_t unused3[8]; + grub_uint32_t rootobject; + grub_uint32_t btree; +} GRUB_PACKED; + +enum + { + FLAGS_CASE_SENSITIVE = 0x80 + }; + +/* 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; + } GRUB_PACKED file; + struct + { + grub_uint32_t hashtable; + grub_uint32_t dir_objc; + } GRUB_PACKED dir; + } file_dir; + grub_uint32_t mtime; + grub_uint8_t type; + grub_uint8_t filename[1]; + grub_uint8_t comment[1]; +} GRUB_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]; +} GRUB_PACKED; + +struct grub_sfs_btree_node +{ + grub_uint32_t key; + grub_uint32_t data; +} GRUB_PACKED; + +struct grub_sfs_btree_extent +{ + grub_uint32_t key; + grub_uint32_t next; + grub_uint32_t prev; + grub_uint16_t size; +} GRUB_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]; +} GRUB_PACKED; + + + +struct cache_entry +{ + grub_uint32_t off; + grub_uint32_t block; +}; + +struct grub_fshelp_node +{ + struct grub_sfs_data *data; + grub_uint32_t block; + grub_uint32_t size; + grub_uint32_t mtime; + grub_uint32_t cache_off; + grub_uint32_t next_extent; + grub_size_t cache_allocated; + grub_size_t cache_size; + struct cache_entry *cache; +}; + +/* Information about a "mounted" sfs filesystem. */ +struct grub_sfs_data +{ + struct grub_sfs_rblock rblock; + struct grub_fshelp_node diropen; + grub_disk_t disk; + + /* Log of blocksize in sectors. */ + int log_blocksize; + + int fshelp_flags; + + /* 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, + grub_uint32_t *size, grub_uint32_t *nextext) +{ + char *treeblock; + struct grub_sfs_btree *tree; + int i; + grub_uint32_t next; + grub_size_t blocksize = GRUB_DISK_SECTOR_SIZE << data->log_blocksize; + + treeblock = grub_malloc (blocksize); + if (!treeblock) + return grub_errno; + + next = grub_be_to_cpu32 (data->rblock.btree); + tree = (struct grub_sfs_btree *) treeblock; + + /* Handle this level in the btree. */ + do + { + grub_uint16_t nnodes; + grub_disk_read (data->disk, + ((grub_disk_addr_t) next) << data->log_blocksize, + 0, blocksize, treeblock); + if (grub_errno) + { + grub_free (treeblock); + return grub_errno; + } + + nnodes = grub_be_to_cpu16 (tree->nodes); + if (nnodes * (grub_uint32_t) (tree)->nodesize > blocksize) + break; + + for (i = (int) nnodes - 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) +{ + grub_uint32_t blk; + grub_uint32_t size = 0; + grub_uint32_t next = 0; + grub_disk_addr_t off; + struct grub_sfs_data *data = node->data; + + /* In case of the first block we don't have to lookup the + extent, the minimum size is always 1. */ + if (fileblock == 0) + return node->block; + + if (!node->cache) + { + grub_size_t cache_size; + /* Assume half-max extents (32768 sectors). */ + cache_size = ((node->size >> (data->log_blocksize + GRUB_DISK_SECTOR_BITS + + 15)) + + 3); + if (cache_size < 8) + cache_size = 8; + + node->cache_off = 0; + node->next_extent = node->block; + node->cache_size = 0; + + node->cache = grub_calloc (cache_size, sizeof (node->cache[0])); + if (!node->cache) + { + grub_errno = 0; + node->cache_allocated = 0; + } + else + { + node->cache_allocated = cache_size; + node->cache[0].off = 0; + node->cache[0].block = node->block; + } + } + + if (fileblock < node->cache_off) + { + unsigned int i = 0; + int j, lg; + for (lg = 0; node->cache_size >> lg; lg++); + + for (j = lg - 1; j >= 0; j--) + if ((i | (1 << j)) < node->cache_size + && node->cache[(i | (1 << j))].off <= fileblock) + i |= (1 << j); + return node->cache[i].block + fileblock - node->cache[i].off; + } + + off = node->cache_off; + blk = node->next_extent; + + while (blk) + { + grub_err_t err; + + err = grub_sfs_read_extent (node->data, blk, &size, &next); + if (err) + return 0; + + if (node->cache && node->cache_size >= node->cache_allocated) + { + struct cache_entry *e = node->cache; + grub_size_t sz; + + if (grub_mul (node->cache_allocated, 2 * sizeof (e[0]), &sz)) + goto fail; + + e = grub_realloc (node->cache, sz); + if (!e) + { + fail: + grub_errno = 0; + grub_free (node->cache); + node->cache = 0; + } + else + { + node->cache_allocated *= 2; + node->cache = e; + } + } + + if (node->cache) + { + node->cache_off = off + size; + node->next_extent = next; + node->cache[node->cache_size].off = off; + node->cache[node->cache_size].block = blk; + node->cache_size++; + } + + if (fileblock - off < size) + return fileblock - off + blk; + + off += 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, + grub_disk_read_hook_t read_hook, void *read_hook_data, + grub_off_t pos, grub_size_t len, char *buf) +{ + return grub_fshelp_read_file (node->data->disk, node, + read_hook, read_hook_data, + pos, len, buf, grub_sfs_read_block, + node->size, node->data->log_blocksize, 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; + grub_uint32_t blk; + unsigned int max_len; + + 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) + || data->rblock.blocksize == 0 + || (data->rblock.blocksize & (data->rblock.blocksize - 1)) != 0 + || (data->rblock.blocksize & grub_cpu_to_be32_compile_time (0xf00001ff))) + { + grub_error (GRUB_ERR_BAD_FS, "not a SFS filesystem"); + goto fail; + } + + for (data->log_blocksize = 9; + (1U << data->log_blocksize) < grub_be_to_cpu32 (data->rblock.blocksize); + data->log_blocksize++); + data->log_blocksize -= GRUB_DISK_SECTOR_BITS; + if (data->rblock.flags & FLAGS_CASE_SENSITIVE) + data->fshelp_flags = 0; + else + data->fshelp_flags = GRUB_FSHELP_CASE_INSENSITIVE; + rootobjc_data = grub_malloc (GRUB_DISK_SECTOR_SIZE << data->log_blocksize); + if (! rootobjc_data) + goto fail; + + /* Read the root object container. */ + grub_disk_read (disk, ((grub_disk_addr_t) grub_be_to_cpu32 (data->rblock.rootobject)) + << data->log_blocksize, 0, + GRUB_DISK_SECTOR_SIZE << data->log_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->diropen.cache = 0; + data->disk = disk; + + /* We only read 1 block of data, so truncate the name if needed. */ + max_len = ((GRUB_DISK_SECTOR_SIZE << data->log_blocksize) + - 24 /* offsetof (struct grub_sfs_objc, objects) */ + - 25); /* offsetof (struct grub_sfs_obj, filename) */ + data->label = grub_zalloc (max_len + 1); + grub_strncpy (data->label, (char *) rootobjc->objects[0].filename, max_len); + + grub_free (rootobjc_data); + 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 (GRUB_DISK_SECTOR_SIZE << data->log_blocksize); + if (!block) + return 0; + + grub_disk_read (data->disk, ((grub_disk_addr_t) node->block) + << data->log_blocksize, + 0, GRUB_DISK_SECTOR_SIZE << data->log_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_malloc (((GRUB_DISK_SECTOR_SIZE << data->log_blocksize) + - 24) * GRUB_MAX_UTF8_PER_LATIN1 + 1); + if (!symlink) + { + grub_free (block); + return 0; + } + *grub_latin1_to_utf8 ((grub_uint8_t *) symlink, (grub_uint8_t *) &block[24], + (GRUB_DISK_SECTOR_SIZE << data->log_blocksize) - 24) = '\0'; + grub_free (block); + return symlink; +} + +/* Helper for grub_sfs_iterate_dir. */ +static int +grub_sfs_create_node (struct grub_fshelp_node **node, + struct grub_sfs_data *data, + const char *name, + grub_uint32_t block, grub_uint32_t size, int type, + grub_uint32_t mtime, + grub_fshelp_iterate_dir_hook_t hook, void *hook_data) +{ + grub_size_t len = grub_strlen (name); + grub_uint8_t *name_u8; + int ret; + grub_size_t sz; + + if (grub_mul (len, GRUB_MAX_UTF8_PER_LATIN1, &sz) || + grub_add (sz, 1, &sz)) + return 1; + + *node = grub_malloc (sizeof (**node)); + if (!*node) + return 1; + name_u8 = grub_malloc (sz); + if (!name_u8) + { + grub_free (*node); + return 1; + } + + (*node)->data = data; + (*node)->size = size; + (*node)->block = block; + (*node)->mtime = mtime; + (*node)->cache = 0; + (*node)->cache_off = 0; + (*node)->next_extent = block; + (*node)->cache_size = 0; + (*node)->cache_allocated = 0; + + *grub_latin1_to_utf8 (name_u8, (const grub_uint8_t *) name, len) = '\0'; + + ret = hook ((char *) name_u8, type | data->fshelp_flags, *node, hook_data); + grub_free (name_u8); + return ret; +} + +static int +grub_sfs_iterate_dir (grub_fshelp_node_t dir, + grub_fshelp_iterate_dir_hook_t hook, void *hook_data) +{ + 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; + grub_uint32_t pos; + + objc_data = grub_malloc (GRUB_DISK_SECTOR_SIZE << data->log_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, ((grub_disk_addr_t) next) + << data->log_blocksize, 0, + GRUB_DISK_SECTOR_SIZE << data->log_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) + < (1U << (GRUB_DISK_SECTOR_BITS + data->log_blocksize))) + { + struct grub_sfs_obj *obj; + obj = (struct grub_sfs_obj *) ((char *) objc + pos); + const char *filename = (const char *) obj->filename; + grub_size_t len; + enum grub_fshelp_filetype type; + grub_uint32_t 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 (filename[0] == 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 (&node, data, filename, block, + grub_be_to_cpu32 (obj->file_dir.file.size), + type, grub_be_to_cpu32 (obj->mtime), + hook, hook_data)) + { + 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) +{ + struct grub_sfs_data *data = (struct grub_sfs_data *) file->data; + + grub_free (data->diropen.cache); + grub_free (data->label); + grub_free (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; + + return grub_sfs_read_file (&data->diropen, + file->read_hook, file->read_hook_data, + file->offset, len, buf); +} + + +/* Context for grub_sfs_dir. */ +struct grub_sfs_dir_ctx +{ + grub_fs_dir_hook_t hook; + void *hook_data; +}; + +/* Helper for grub_sfs_dir. */ +static int +grub_sfs_dir_iter (const char *filename, enum grub_fshelp_filetype filetype, + grub_fshelp_node_t node, void *data) +{ + struct grub_sfs_dir_ctx *ctx = data; + struct grub_dirhook_info info; + + grub_memset (&info, 0, sizeof (info)); + info.dir = ((filetype & GRUB_FSHELP_TYPE_MASK) == GRUB_FSHELP_DIR); + info.mtime = node->mtime + 8 * 365 * 86400 + 86400 * 2; + info.mtimeset = 1; + grub_free (node->cache); + grub_free (node); + return ctx->hook (filename, &info, ctx->hook_data); +} + +static grub_err_t +grub_sfs_dir (grub_device_t device, const char *path, + grub_fs_dir_hook_t hook, void *hook_data) +{ + struct grub_sfs_dir_ctx ctx = { hook, hook_data }; + struct grub_sfs_data *data = 0; + struct grub_fshelp_node *fdiro = 0; + + 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, grub_sfs_dir_iter, &ctx); + + 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) + { + grub_size_t sz, len = grub_strlen (data->label); + + if (grub_mul (len, GRUB_MAX_UTF8_PER_LATIN1, &sz) || + grub_add (sz, 1, &sz)) + return GRUB_ERR_OUT_OF_RANGE; + + *label = grub_malloc (sz); + if (*label) + *grub_latin1_to_utf8 ((grub_uint8_t *) *label, + (const grub_uint8_t *) data->label, + len) = '\0'; + grub_free (data->label); + } + grub_free (data); + + return grub_errno; +} + + +static struct grub_fs grub_sfs_fs = + { + .name = "sfs", + .fs_dir = grub_sfs_dir, + .fs_open = grub_sfs_open, + .fs_read = grub_sfs_read, + .fs_close = grub_sfs_close, + .fs_label = grub_sfs_label, +#ifdef GRUB_UTIL + .reserved_first_sector = 0, + .blocklist_install = 1, +#endif + .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); +} |