aboutsummaryrefslogtreecommitdiffstats
path: root/grub-core/fs/sfs.c
diff options
context:
space:
mode:
Diffstat (limited to 'grub-core/fs/sfs.c')
-rw-r--r--grub-core/fs/sfs.c599
1 files changed, 599 insertions, 0 deletions
diff --git a/grub-core/fs/sfs.c b/grub-core/fs/sfs.c
new file mode 100644
index 0000000..4557431
--- /dev/null
+++ b/grub-core/fs/sfs.c
@@ -0,0 +1,599 @@
+/* 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>
+
+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;
+} __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;
+
+ 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
+ {
+ 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,
+#ifdef GRUB_UTIL
+ .reserved_first_sector = 0,
+#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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-20 23:35:24 +0000