--- /dev/null
+/* iso9660.c - iso9660 implementation with extensions:
+ SUSP, Rock Ridge. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2004 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 <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>
+
+#define GRUB_ISO9660_FSTYPE_DIR 0040000
+#define GRUB_ISO9660_FSTYPE_REG 0100000
+#define GRUB_ISO9660_FSTYPE_SYMLINK 0120000
+#define GRUB_ISO9660_FSTYPE_MASK 0170000
+
+#define GRUB_ISO9660_LOG2_BLKSZ 2
+#define GRUB_ISO9660_BLKSZ 2048
+
+#define GRUB_ISO9660_RR_DOT 2
+#define GRUB_ISO9660_RR_DOTDOT 4
+
+/* The head of a volume descriptor. */
+struct grub_iso9660_voldesc
+{
+ grub_uint8_t type;
+ grub_uint8_t magic[5];
+ grub_uint8_t version;
+} __attribute__ ((packed));
+
+/* A directory entry. */
+struct grub_iso9660_dir
+{
+ grub_uint8_t len;
+ grub_uint8_t ext_sectors;
+ grub_uint32_t first_sector;
+ grub_uint32_t first_sector_be;
+ grub_uint32_t size;
+ grub_uint32_t size_be;
+ grub_uint8_t unused1[7];
+ grub_uint8_t flags;
+ grub_uint8_t unused2[6];
+ grub_uint8_t namelen;
+} __attribute__ ((packed));
+
+/* The primary volume descriptor. Only little endian is used. */
+struct grub_iso9660_primary_voldesc
+{
+ struct grub_iso9660_voldesc voldesc;
+ grub_uint8_t unused1[33];
+ grub_uint8_t volname[32];
+ grub_uint8_t unused2[60];
+ grub_uint32_t path_table_size;
+ grub_uint8_t unused3[4];
+ grub_uint32_t path_table;
+ grub_uint8_t unused4[12];
+ struct grub_iso9660_dir rootdir;
+} __attribute__ ((packed));
+
+/* A single entry in the path table. */
+struct grub_iso9660_path
+{
+ grub_uint8_t len;
+ grub_uint8_t sectors;
+ grub_uint32_t first_sector;
+ grub_uint16_t parentdir;
+ grub_uint8_t name[0];
+} __attribute__ ((packed));
+
+/* An entry in the System Usage area of the directory entry. */
+struct grub_iso9660_susp_entry
+{
+ grub_uint8_t sig[2];
+ grub_uint8_t len;
+ grub_uint8_t version;
+ grub_uint8_t data[0];
+} __attribute__ ((packed));
+
+/* The CE entry. This is used to describe the next block where data
+ can be found. */
+struct grub_iso9660_susp_ce
+{
+ struct grub_iso9660_susp_entry entry;
+ grub_uint32_t blk;
+ grub_uint32_t blk_be;
+ grub_uint32_t off;
+ grub_uint32_t off_be;
+ grub_uint32_t len;
+ grub_uint32_t len_be;
+} __attribute__ ((packed));
+
+struct grub_iso9660_data
+{
+ struct grub_iso9660_primary_voldesc voldesc;
+ grub_disk_t disk;
+ unsigned int first_sector;
+ unsigned int length;
+ int rockridge;
+ int susp_skip;
+};
+
+struct grub_fshelp_node
+{
+ struct grub_iso9660_data *data;
+ unsigned int size;
+ unsigned int blk;
+ unsigned int dir_blk;
+ unsigned int dir_off;
+};
+
+#ifndef GRUB_UTIL
+static grub_dl_t my_mod;
+#endif
+\f
+
+/* Iterate over the susp entries, starting with block SUA_BLOCK on the
+ offset SUA_POS with a size of SUA_SIZE bytes. Hook is called for
+ every entry. */
+static grub_err_t
+grub_iso9660_susp_iterate (struct grub_iso9660_data *data,
+ int sua_block, int sua_pos, int sua_size,
+ grub_err_t (*hook)
+ (struct grub_iso9660_susp_entry *entry))
+{
+ char *sua;
+ struct grub_iso9660_susp_entry *entry;
+
+ auto grub_err_t load_sua (void);
+
+ /* Load a part of the System Usage Area. */
+ grub_err_t load_sua (void)
+ {
+ sua = grub_malloc (sua_size);
+ if (!sua)
+ return grub_errno;
+
+ if (grub_disk_read (data->disk, sua_block, sua_pos,
+ sua_size, sua))
+ return grub_errno;
+
+ entry = (struct grub_iso9660_susp_entry *) sua;
+ return 0;
+ }
+
+ if (load_sua ())
+ return grub_errno;
+
+ for (; (char *) entry < (char *) sua + sua_size - 1;
+ entry = (struct grub_iso9660_susp_entry *)
+ ((char *) entry + entry->len))
+ {
+ /* The last entry. */
+ if (!grub_strncmp (entry->sig, "ST", 2))
+ break;
+
+ /* Additional entries are stored elsewhere. */
+ if (!grub_strncmp (entry->sig, "CE", 2))
+ {
+ struct grub_iso9660_susp_ce *ce;
+
+ ce = (struct grub_iso9660_susp_ce *) entry;
+ sua_size = grub_le_to_cpu32 (ce->len);
+ sua_pos = grub_le_to_cpu32 (ce->off);
+ sua_block = grub_le_to_cpu32 (ce->blk) << GRUB_ISO9660_LOG2_BLKSZ;
+
+ grub_free (sua);
+ if (load_sua ())
+ return grub_errno;
+ }
+
+ if (hook (entry))
+ {
+ grub_free (sua);
+ return 0;
+ }
+ }
+
+ grub_free (sua);
+ return 0;
+}
+
+
+static struct grub_iso9660_data *
+grub_iso9660_mount (grub_disk_t disk)
+{
+ struct grub_iso9660_data *data = 0;
+ struct grub_iso9660_dir rootdir;
+ int sua_pos;
+ int sua_size;
+ char *sua;
+ struct grub_iso9660_susp_entry *entry;
+
+ auto grub_err_t susp_iterate (struct grub_iso9660_susp_entry *);
+
+ grub_err_t susp_iterate (struct grub_iso9660_susp_entry *susp_entry)
+ {
+ /* The "ER" entry is used to detect extensions. The
+ `IEEE_P1285' extension means Rock ridge. */
+ if (!grub_strncmp (susp_entry->sig, "ER", 2))
+ {
+ data->rockridge = 1;
+ return 1;
+ }
+ return 0;
+ }
+
+ data = grub_malloc (sizeof (struct grub_iso9660_data));
+ if (!data)
+ return 0;
+
+ /* Read the superblock. */
+ if (grub_disk_read (disk, 16 << GRUB_ISO9660_LOG2_BLKSZ, 0,
+ sizeof (struct grub_iso9660_primary_voldesc),
+ (char *) &data->voldesc))
+ {
+ grub_error (GRUB_ERR_BAD_FS, "not a iso9660 filesystem");
+ goto fail;
+ }
+
+ if (grub_strncmp (data->voldesc.voldesc.magic, "CD001", 5))
+ {
+ grub_error (GRUB_ERR_BAD_FS, "not a iso9660 filesystem");
+ goto fail;
+ }
+
+ data->disk = disk;
+ data->rockridge = 0;
+
+ /* Read the system use area and test it to see if SUSP is
+ supported. */
+ if (grub_disk_read (disk, (grub_le_to_cpu32 (data->voldesc.rootdir.first_sector)
+ << GRUB_ISO9660_LOG2_BLKSZ), 0,
+ sizeof (rootdir), (char *) &rootdir))
+ {
+ grub_error (GRUB_ERR_BAD_FS, "not a iso9660 filesystem");
+ goto fail;
+ }
+
+ if (grub_disk_read (disk, (grub_le_to_cpu32 (data->voldesc.rootdir.first_sector)
+ << GRUB_ISO9660_LOG2_BLKSZ), 0,
+ sizeof (rootdir), (char *) &rootdir))
+ {
+ grub_error (GRUB_ERR_BAD_FS, "not a iso9660 filesystem");
+ goto fail;
+ }
+
+ sua_pos = (sizeof (rootdir) + rootdir.namelen
+ + (rootdir.namelen % 2) - 1);
+ sua_size = rootdir.len - sua_pos;
+
+ sua = grub_malloc (sua_size);
+ if (!sua)
+ goto fail;
+
+ if (grub_disk_read (disk, (grub_le_to_cpu32 (data->voldesc.rootdir.first_sector)
+ << GRUB_ISO9660_LOG2_BLKSZ), sua_pos,
+ sua_size, sua))
+ {
+ grub_error (GRUB_ERR_BAD_FS, "not a iso9660 filesystem");
+ goto fail;
+ }
+
+ entry = (struct grub_iso9660_susp_entry *) sua;
+
+ /* Test if the SUSP protocol is used on this filesystem. */
+ if (!grub_strncmp (entry->sig, "SP", 2))
+ {
+ /* The 2nd data byte stored how many bytes are skipped everytime
+ to get to the SUA (System Usage Area). */
+ data->susp_skip = entry->data[2];
+ entry = (struct grub_iso9660_susp_entry *) ((char *) entry + entry->len);
+
+ /* Iterate over the entries in the SUA area to detect
+ entensions. */
+ if (grub_iso9660_susp_iterate (data,
+ (grub_le_to_cpu32 (data->voldesc.rootdir.first_sector)
+ << GRUB_ISO9660_LOG2_BLKSZ),
+ sua_pos, sua_size, susp_iterate))
+ goto fail;
+ }
+
+ return data;
+
+ fail:
+ grub_free (data);
+ return 0;
+}
+
+
+static char *
+grub_iso9660_read_symlink (grub_fshelp_node_t node)
+{
+ struct grub_iso9660_dir dirent;
+ int sua_off;
+ int sua_size;
+ char *symlink = 0;
+ int addslash = 0;
+
+ auto void add_part (const char *part, int len);
+ auto grub_err_t susp_iterate_sl (struct grub_iso9660_susp_entry *);
+
+ /* Extend the symlink. */
+ void add_part (const char *part, int len)
+ {
+ int size = grub_strlen (symlink);
+
+ symlink = grub_realloc (symlink, size + len + 1);
+ if (!symlink)
+ return;
+ grub_strncat (symlink, part, len);
+
+ return;
+ }
+
+ /* Read in a symlink. */
+ grub_err_t susp_iterate_sl (struct grub_iso9660_susp_entry *entry)
+ {
+ if (!grub_strncmp ("SL", entry->sig, 2))
+ {
+ unsigned int pos = 1;
+
+ /* The symlink is not stored as a POSIX symlink, translate it. */
+ while (pos < grub_le_to_cpu32 (entry->len))
+ {
+ if (addslash)
+ {
+ add_part ("/", 1);
+ addslash = 0;
+ }
+
+ /* The current position is the `Component Flag'. */
+ switch (entry->data[pos] & 30)
+ {
+ case 0:
+ {
+ /* The data on pos + 2 is the actual data, pos + 1
+ is the length. Both are part of the `Component
+ Record'. */
+ add_part (&entry->data[pos + 2],
+ entry->data[pos + 1]);
+ if ((entry->data[pos] & 1))
+ addslash = 1;
+
+ break;
+ }
+
+ case 2:
+ add_part ("./", 2);
+ break;
+
+ case 4:
+ add_part ("../", 3);
+ break;
+
+ case 8:
+ add_part ("/", 1);
+ break;
+ }
+ /* In pos + 1 the length of the `Component Record' is
+ stored. */
+ pos += entry->data[pos + 1] + 2;
+ }
+
+ /* Check if `grub_realloc' failed. */
+ if (grub_errno)
+ return grub_errno;
+ }
+
+ return 0;
+ }
+
+ if (grub_disk_read (node->data->disk, node->dir_blk, node->dir_off,
+ sizeof (dirent), (char *) &dirent))
+ return 0;
+
+ sua_off = (sizeof (dirent) + dirent.namelen + 1 - (dirent.namelen % 2)
+ + node->data->susp_skip);
+ sua_size = dirent.len - sua_off;
+
+ symlink = grub_malloc (1);
+ if (!symlink)
+ return 0;
+
+ *symlink = '\0';
+
+ if (grub_iso9660_susp_iterate (node->data, node->dir_blk,
+ node->dir_off + sua_off,
+ sua_size, susp_iterate_sl))
+ {
+ grub_free (symlink);
+ return 0;
+ }
+
+ return symlink;
+}
+
+
+static int
+grub_iso9660_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_iso9660_dir dirent;
+ unsigned int offset = 0;
+ char *filename;
+ int filename_alloc = 0;
+ enum grub_fshelp_filetype type;
+
+ auto grub_err_t susp_iterate_dir (struct grub_iso9660_susp_entry *);
+
+ grub_err_t susp_iterate_dir (struct grub_iso9660_susp_entry *entry)
+ {
+ /* The filename in the rock ridge entry. */
+ if (!grub_strncmp ("NM", entry->sig, 2))
+ {
+ /* The flags are stored at the data position 0, here the
+ filename type is stored. */
+ if (entry->data[0] & GRUB_ISO9660_RR_DOT)
+ filename = ".";
+ else if (entry->data[0] & GRUB_ISO9660_RR_DOTDOT)
+ filename = "..";
+ else
+ {
+ int size = 1;
+ if (filename)
+ {
+ size += grub_strlen (filename);
+ grub_realloc (filename,
+ grub_strlen (filename)
+ + entry->len);
+ }
+ else
+ {
+ size = entry->len - 5;
+ filename = grub_malloc (size + 1);
+ filename[0] = '\0';
+ }
+ filename_alloc = 1;
+ grub_strncpy (filename, &entry->data[1], size);
+ filename [size] = '\0';
+ }
+ }
+ /* The mode information (st_mode). */
+ else if (!grub_strncmp (entry->sig, "PX", 2))
+ {
+ /* At position 0 of the PX record the st_mode information is
+ stored. */
+ grub_uint32_t mode = ((*(grub_uint32_t *) &entry->data[0])
+ & GRUB_ISO9660_FSTYPE_MASK);
+
+ switch (mode)
+ {
+ case GRUB_ISO9660_FSTYPE_DIR:
+ type = GRUB_FSHELP_DIR;
+ break;
+ case GRUB_ISO9660_FSTYPE_REG:
+ type = GRUB_FSHELP_REG;
+ break;
+ case GRUB_ISO9660_FSTYPE_SYMLINK:
+ type = GRUB_FSHELP_SYMLINK;
+ break;
+ default:
+ type = GRUB_FSHELP_UNKNOWN;
+ }
+ }
+
+ return 0;
+ }
+
+ while (offset < dir->size)
+ {
+ if (grub_disk_read (dir->data->disk,
+ (dir->blk << GRUB_ISO9660_LOG2_BLKSZ)
+ + offset / GRUB_DISK_SECTOR_SIZE,
+ offset % GRUB_DISK_SECTOR_SIZE,
+ sizeof (dirent), (char *) &dirent))
+ return 0;
+
+ /* The end of the block, skip to the next one. */
+ if (!dirent.len)
+ {
+ offset = (offset / GRUB_ISO9660_BLKSZ + 1) * GRUB_ISO9660_BLKSZ;
+ continue;
+ }
+
+ {
+ char name[dirent.namelen + 1];
+ int nameoffset = offset + sizeof (dirent);
+ struct grub_fshelp_node *node;
+ int sua_off = (sizeof (dirent) + dirent.namelen + 1
+ - (dirent.namelen % 2));;
+ int sua_size = dirent.len - sua_off;
+
+ sua_off += offset + dir->data->susp_skip;
+
+ filename = 0;
+ filename_alloc = 0;
+ type = GRUB_FSHELP_UNKNOWN;
+
+ if (dir->data->rockridge
+ && grub_iso9660_susp_iterate (dir->data,
+ (dir->blk << GRUB_ISO9660_LOG2_BLKSZ)
+ + (sua_off
+ / GRUB_DISK_SECTOR_SIZE),
+ sua_off % GRUB_DISK_SECTOR_SIZE,
+ sua_size, susp_iterate_dir))
+ return 0;
+
+ /* Read the name. */
+ if (grub_disk_read (dir->data->disk,
+ (dir->blk << GRUB_ISO9660_LOG2_BLKSZ)
+ + nameoffset / GRUB_DISK_SECTOR_SIZE,
+ nameoffset % GRUB_DISK_SECTOR_SIZE,
+ dirent.namelen, (char *) name))
+ return 0;
+
+ node = grub_malloc (sizeof (struct grub_fshelp_node));
+ if (!node)
+ return 0;
+
+ /* Setup a new node. */
+ node->data = dir->data;
+ node->size = grub_le_to_cpu32 (dirent.size);
+ node->blk = grub_le_to_cpu32 (dirent.first_sector);
+ node->dir_blk = ((dir->blk << GRUB_ISO9660_LOG2_BLKSZ)
+ + offset / GRUB_DISK_SECTOR_SIZE);
+ node->dir_off = offset % GRUB_DISK_SECTOR_SIZE;
+
+ /* If the filetype was not stored using rockridge, use
+ whatever is stored in the iso9660 filesystem. */
+ if (type == GRUB_FSHELP_UNKNOWN)
+ {
+ if ((dirent.flags & 3) == 2)
+ type = GRUB_FSHELP_DIR;
+ else
+ type = GRUB_FSHELP_REG;
+ }
+
+ /* The filename was not stored in a rock ridge entry. Read it
+ from the iso9660 filesystem. */
+ if (!filename)
+ {
+ name[dirent.namelen] = '\0';
+ filename = grub_strrchr (name, ';');
+ if (filename)
+ *filename = '\0';
+
+ if (dirent.namelen == 1 && name[0] == 0)
+ filename = ".";
+ else if (dirent.namelen == 1 && name[0] == 1)
+ filename = "..";
+ else
+ filename = name;
+ }
+
+ if (hook (filename, type, node))
+ {
+ if (filename_alloc)
+ grub_free (filename);
+ return 1;
+ }
+ if (filename_alloc)
+ grub_free (filename);
+ }
+
+ offset += dirent.len;
+ }
+
+ return 0;
+}
+
+
+\f
+static grub_err_t
+grub_iso9660_dir (grub_device_t device, const char *path,
+ int (*hook) (const char *filename, int dir))
+{
+ struct grub_iso9660_data *data = 0;
+ struct grub_fshelp_node rootnode;
+ struct grub_fshelp_node *foundnode;
+
+ 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)
+ {
+ grub_free (node);
+
+ if (filetype == GRUB_FSHELP_DIR)
+ return hook (filename, 1);
+ else
+ return hook (filename, 0);
+
+ return 0;
+ }
+
+#ifndef GRUB_UTIL
+ grub_dl_ref (my_mod);
+#endif
+
+ data = grub_iso9660_mount (device->disk);
+ if (!data)
+ goto fail;
+
+ rootnode.data = data;
+ rootnode.blk = grub_le_to_cpu32 (data->voldesc.rootdir.first_sector);
+ rootnode.size = grub_le_to_cpu32 (data->voldesc.rootdir.size);
+
+ /* Use the fshelp function to traverse the path. */
+ if (grub_fshelp_find_file (path, &rootnode,
+ &foundnode,
+ grub_iso9660_iterate_dir,
+ grub_iso9660_read_symlink,
+ GRUB_FSHELP_DIR))
+ goto fail;
+
+ /* List the files in the directory. */
+ grub_iso9660_iterate_dir (foundnode, iterate);
+
+ if (foundnode != &rootnode)
+ grub_free (foundnode);
+
+ fail:
+ 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_iso9660_open (struct grub_file *file, const char *name)
+{
+ struct grub_iso9660_data *data;
+ struct grub_fshelp_node rootnode;
+ struct grub_fshelp_node *foundnode;
+
+#ifndef GRUB_UTIL
+ grub_dl_ref (my_mod);
+#endif
+
+ data = grub_iso9660_mount (file->device->disk);
+ if (!data)
+ goto fail;
+
+ rootnode.data = data;
+ rootnode.blk = grub_le_to_cpu32 (data->voldesc.rootdir.first_sector);
+ rootnode.size = grub_le_to_cpu32 (data->voldesc.rootdir.size);
+
+ /* Use the fshelp function to traverse the path. */
+ if (grub_fshelp_find_file (name, &rootnode,
+ &foundnode,
+ grub_iso9660_iterate_dir,
+ grub_iso9660_read_symlink,
+ GRUB_FSHELP_REG))
+ goto fail;
+
+ data->first_sector = foundnode->blk;
+ data->length = foundnode->size;
+
+ file->data = data;
+ file->size = foundnode->size;
+ file->offset = 0;
+
+ return 0;
+
+ fail:
+#ifndef GRUB_UTIL
+ grub_dl_unref (my_mod);
+#endif
+
+ grub_free (data);
+
+ return grub_errno;;
+}
+
+
+static grub_ssize_t
+grub_iso9660_read (grub_file_t file, char *buf, grub_ssize_t len)
+{
+ struct grub_iso9660_data *data =
+ (struct grub_iso9660_data *) file->data;
+
+ /* XXX: The file is stored in as a single extent. */
+ data->disk->read_hook = file->read_hook;
+ grub_disk_read (data->disk,
+ data->first_sector << GRUB_ISO9660_LOG2_BLKSZ,
+ file->offset,
+ len, buf);
+ data->disk->read_hook = 0;
+
+ return len;
+}
+
+
+static grub_err_t
+grub_iso9660_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_iso9660_label (grub_device_t device, char **label)
+{
+ struct grub_iso9660_data *data;
+ data = grub_iso9660_mount (device->disk);
+
+ if (data)
+ {
+ *label = grub_strndup (data->voldesc.volname, 32);
+ grub_free (data);
+ }
+ else
+ *label = 0;
+
+ return grub_errno;
+}
+
+\f
+
+static struct grub_fs grub_iso9660_fs =
+ {
+ .name = "iso9660",
+ .dir = grub_iso9660_dir,
+ .open = grub_iso9660_open,
+ .read = grub_iso9660_read,
+ .close = grub_iso9660_close,
+ .label = grub_iso9660_label,
+ .next = 0
+ };
+
+#ifdef GRUB_UTIL
+void
+grub_iso9660_init (void)
+{
+ grub_fs_register (&grub_iso9660_fs);
+}
+
+void
+grub_iso9660_fini (void)
+{
+ grub_fs_unregister (&grub_iso9660_fs);
+}
+#else /* ! GRUB_UTIL */
+GRUB_MOD_INIT
+{
+ grub_fs_register (&grub_iso9660_fs);
+ my_mod = mod;
+}
+
+GRUB_MOD_FINI
+{
+ grub_fs_unregister (&grub_iso9660_fs);
+}
+#endif /* ! GRUB_UTIL */
projects / thirdparty / grub.git / commitdiff
