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Diffstat (limited to 'extras/volume_id/volume_id.c')
-rw-r--r--extras/volume_id/volume_id.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/extras/volume_id/volume_id.c b/extras/volume_id/volume_id.c
new file mode 100644
index 0000000000..cc5475fc8d
--- /dev/null
+++ b/extras/volume_id/volume_id.c
@@ -0,0 +1,550 @@
+/*
+ * volume_id - reads filesystem label and uuid
+ *
+ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * The superblock structs are taken from the libblkid living inside
+ * the e2fsprogs. This is a simple straightforward implementation for
+ * reading the label strings of only the most common filesystems.
+ * If you need a full featured library with attribute caching, support for
+ * much more partition/media types or non-root data access, you may have
+ * a look at:
+ * http://e2fsprogs.sourceforge.net.
+ *
+ * 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 version 2 of the License.
+ *
+ * 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 <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <asm/types.h>
+
+#include "volume_id.h"
+
+
+#define bswap32(x) (__u32)((((__u32)(x) & 0xff000000u) >> 24) | \
+ (((__u32)(x) & 0x00ff0000u) >> 8) | \
+ (((__u32)(x) & 0x0000ff00u) << 8) | \
+ (((__u32)(x) & 0x000000ffu) << 24))
+
+#if (__BYTE_ORDER == __LITTLE_ENDIAN)
+#define cpu_to_le32(x) (x)
+#elif (__BYTE_ORDER == __BIG_ENDIAN)
+#define cpu_to_le32(x) bswap32(x)
+#endif
+
+#define VOLUME_ID_BUFFER_SIZE 0x11000 /* reiser offset is 64k */
+
+
+static void set_label(struct volume_id *id, char *buf, int count)
+{
+ int i;
+
+ memcpy(id->label, buf, count);
+
+ memcpy(id->label_string, buf, count);
+
+ /* remove trailing whitespace */
+ i = strlen(id->label_string);
+ while (i--) {
+ if (! isspace(id->label_string[i]))
+ break;
+ }
+ id->label_string[i+1] = '\0';
+}
+
+static void set_uuid(struct volume_id *id, unsigned char *buf, int count)
+{
+ int i;
+
+ memcpy(id->uuid, buf, count);
+
+ /* create string if uuid is set */
+ for (i = 0; i < count; i++)
+ if (buf[i] != 0)
+ goto set;
+ return;
+
+set:
+ switch(count) {
+ case 4:
+ sprintf(id->uuid_string, "%02X%02X-%02X%02X",
+ buf[3], buf[2], buf[1], buf[0]);
+ break;
+ case 16:
+ sprintf(id->uuid_string,
+ "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+ buf[0], buf[1], buf[2], buf[3],
+ buf[4], buf[5],
+ buf[6], buf[7],
+ buf[8], buf[9],
+ buf[10], buf[11], buf[12], buf[13], buf[14],buf[15]);
+ break;
+ }
+}
+
+static int open_superblock(struct volume_id *id)
+{
+ /* get buffer to read the first block */
+ if (id->buf == NULL) {
+ id->buf = malloc(VOLUME_ID_BUFFER_SIZE);
+ if (id->buf == NULL)
+ return -1;
+ }
+
+ /* try to read the first 64k, but at least the first block */
+ memset(id->buf, 0x00, VOLUME_ID_BUFFER_SIZE);
+ lseek(id->fd, 0, SEEK_SET);
+ if (read(id->fd, id->buf, VOLUME_ID_BUFFER_SIZE) < 0x200)
+ return -1;
+
+ return 0;
+}
+
+static void close_superblock(struct volume_id *id)
+{
+ if (id->buf != NULL) {
+ free(id->buf);
+ id->buf = NULL;
+ }
+}
+
+#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x00000004
+#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x00000008
+#define EXT_SUPERBLOCK_OFFSET 0x400
+static int probe_ext(struct volume_id *id)
+{
+ struct ext2_super_block {
+ __u32 s_inodes_count;
+ __u32 s_blocks_count;
+ __u32 s_r_blocks_count;
+ __u32 s_free_blocks_count;
+ __u32 s_free_inodes_count;
+ __u32 s_first_data_block;
+ __u32 s_log_block_size;
+ __u32 s_dummy3[7];
+ unsigned char s_magic[2];
+ __u16 s_state;
+ __u32 s_dummy5[8];
+ __u32 s_feature_compat;
+ __u32 s_feature_incompat;
+ __u32 s_feature_ro_compat;
+ unsigned char s_uuid[16];
+ char s_volume_name[16];
+ } *es;
+
+ es = (struct ext2_super_block *) (id->buf + EXT_SUPERBLOCK_OFFSET);
+
+ if (es->s_magic[0] != 0123 ||
+ es->s_magic[1] != 0357)
+ return -1;
+
+ set_label(id, es->s_volume_name, 16);
+ set_uuid(id, es->s_uuid, 16);
+
+ if ((cpu_to_le32(es->s_feature_compat) & EXT3_FEATURE_COMPAT_HAS_JOURNAL) != 0) {
+ id->fs_type = EXT3;
+ id->fs_name = "ext3";
+ } else {
+ id->fs_type = EXT2;
+ id->fs_name = "ext2";
+ }
+
+ return 0;
+}
+
+#define REISER1_SUPERBLOCK_OFFSET 0x2000
+#define REISER_SUPERBLOCK_OFFSET 0x10000
+static int probe_reiser(struct volume_id *id)
+{
+ struct reiser_super_block {
+ __u32 rs_blocks_count;
+ __u32 rs_free_blocks;
+ __u32 rs_root_block;
+ __u32 rs_journal_block;
+ __u32 rs_journal_dev;
+ __u32 rs_orig_journal_size;
+ __u32 rs_dummy2[5];
+ __u16 rs_blocksize;
+ __u16 rs_dummy3[3];
+ unsigned char rs_magic[12];
+ __u32 rs_dummy4[5];
+ unsigned char rs_uuid[16];
+ char rs_label[16];
+ } *rs;
+
+ rs = (struct reiser_super_block *) &(id->buf[REISER1_SUPERBLOCK_OFFSET]);
+
+ if (strncmp(rs->rs_magic, "ReIsErFs", 8) == 0)
+ goto found;
+
+ rs = (struct reiser_super_block *) &(id->buf[REISER_SUPERBLOCK_OFFSET]);
+
+ if (strncmp(rs->rs_magic, "ReIsEr2Fs", 9) == 0)
+ goto found;
+ if (strncmp(rs->rs_magic, "ReIsEr3Fs", 9) == 0)
+ goto found;
+
+ return -1;
+
+found:
+ set_label(id, rs->rs_label, 16);
+ set_uuid(id, rs->rs_uuid, 16);
+
+ id->fs_type = REISER;
+ id->fs_name = "reiser";
+
+ return 0;
+}
+
+static int probe_xfs(struct volume_id *id)
+{
+ struct xfs_super_block {
+ unsigned char xs_magic[4];
+ __u32 xs_blocksize;
+ __u64 xs_dblocks;
+ __u64 xs_rblocks;
+ __u32 xs_dummy1[2];
+ unsigned char xs_uuid[16];
+ __u32 xs_dummy2[15];
+ char xs_fname[12];
+ __u32 xs_dummy3[2];
+ __u64 xs_icount;
+ __u64 xs_ifree;
+ __u64 xs_fdblocks;
+ } *xs;
+
+ xs = (struct xfs_super_block *) id->buf;
+
+ if (strncmp(xs->xs_magic, "XFSB", 4) != 0)
+ return -1;
+
+ set_label(id, xs->xs_fname, 12);
+ set_uuid(id, xs->xs_uuid, 16);
+
+ id->fs_type = XFS;
+ id->fs_name = "xfs";
+
+ return 0;
+}
+
+#define JFS_SUPERBLOCK_OFFSET 0x8000
+static int probe_jfs(struct volume_id *id)
+{
+ struct jfs_super_block {
+ unsigned char js_magic[4];
+ __u32 js_version;
+ __u64 js_size;
+ __u32 js_bsize;
+ __u32 js_dummy1;
+ __u32 js_pbsize;
+ __u32 js_dummy2[27];
+ unsigned char js_uuid[16];
+ unsigned char js_label[16];
+ unsigned char js_loguuid[16];
+ } *js;
+
+ js = (struct jfs_super_block *) &(id->buf[JFS_SUPERBLOCK_OFFSET]);
+
+ if (strncmp(js->js_magic, "JFS1", 4) != 0)
+ return -1;
+
+ set_label(id, js->js_label, 16);
+ set_uuid(id, js->js_uuid, 16);
+
+ id->fs_type = JFS;
+ id->fs_name = "jfs";
+
+ return 0;
+}
+
+static int probe_vfat(struct volume_id *id)
+{
+ struct vfat_super_block {
+ unsigned char vs_ignored[3];
+ unsigned char vs_sysid[8];
+ unsigned char vs_sector_size[2];
+ __u8 vs_cluster_size;
+ __u16 vs_reserved;
+ __u8 vs_fats;
+ unsigned char vs_dir_entries[2];
+ unsigned char vs_sectors[2];
+ unsigned char vs_media;
+ __u16 vs_fat_length;
+ __u16 vs_secs_track;
+ __u16 vs_heads;
+ __u32 vs_hidden;
+ __u32 vs_total_sect;
+ __u32 vs_fat32_length;
+ __u16 vs_flags;
+ __u8 vs_version[2];
+ __u32 vs_root_cluster;
+ __u16 vs_insfo_sector;
+ __u16 vs_backup_boot;
+ __u16 vs_reserved2[6];
+ unsigned char vs_unknown[3];
+ unsigned char vs_serno[4];
+ char vs_label[11];
+ unsigned char vs_magic[8];
+ unsigned char vs_dummy2[164];
+ unsigned char vs_pmagic[2];
+ } *vs;
+
+ vs = (struct vfat_super_block *) id->buf;
+
+ if (strncmp(vs->vs_magic, "MSWIN", 5) == 0)
+ goto found;
+ if (strncmp(vs->vs_magic, "FAT32 ", 8) == 0)
+ goto found;
+ return -1;
+
+found:
+ memcpy(id->label, vs->vs_label, 11);
+ memcpy(id->uuid, vs->vs_serno, 4);
+
+ id->fs_type = VFAT;
+ id->fs_name = "vfat";
+
+ return 0;
+}
+
+static int probe_msdos(struct volume_id *id)
+{
+ struct msdos_super_block {
+ unsigned char ms_ignored[3];
+ unsigned char ms_sysid[8];
+ unsigned char ms_sector_size[2];
+ __u8 ms_cluster_size;
+ __u16 ms_reserved;
+ __u8 ms_fats;
+ unsigned char ms_dir_entries[2];
+ unsigned char ms_sectors[2];
+ unsigned char ms_media;
+ __u16 ms_fat_length;
+ __u16 ms_secs_track;
+ __u16 ms_heads;
+ __u32 ms_hidden;
+ __u32 ms_total_sect;
+ unsigned char ms_unknown[3];
+ unsigned char ms_serno[4];
+ char ms_label[11];
+ unsigned char ms_magic[8];
+ unsigned char ms_dummy2[192];
+ unsigned char ms_pmagic[2];
+ } *ms;
+
+ ms = (struct msdos_super_block *) id->buf;
+
+ if (strncmp(ms->ms_magic, "MSDOS", 5) == 0)
+ goto found;
+ if (strncmp(ms->ms_magic, "FAT16 ", 8) == 0)
+ goto found;
+ if (strncmp(ms->ms_magic, "FAT12 ", 8) == 0)
+ goto found;
+ return -1;
+
+found:
+ set_label(id, ms->ms_label, 11);
+ set_uuid(id, ms->ms_serno, 4);
+
+ id->fs_type = MSDOS;
+ id->fs_name = "msdos";
+
+ return 0;
+}
+
+static int probe_ntfs(struct volume_id *id)
+{
+ struct ntfs_super_block {
+ char jump[3];
+ char oem_id[4];
+ } *ns;
+
+ ns = (struct ntfs_super_block *) id->buf;
+
+ if (strncmp(ns->oem_id, "NTFS", 4) != 0)
+ return -1;
+
+ id->fs_type = NTFS;
+ id->fs_name = "ntfs";
+
+ return 0;
+}
+
+static int probe_swap(struct volume_id *id)
+{
+ int magic;
+
+ /* huhh, the swap signature is on the end of the PAGE_SIZE */
+ for (magic = 0x1000; magic <= 0x4000; magic <<= 1) {
+ if (strncmp(&(id->buf[magic -10]), "SWAP-SPACE", 10) == 0)
+ goto found;
+ if (strncmp(&(id->buf[magic -10]), "SWAPSPACE2", 10) == 0)
+ goto found;
+ }
+ return -1;
+
+found:
+ id->fs_type = SWAP;
+ id->fs_name = "swap";
+
+ return 0;
+}
+
+/* probe volume for filesystem type and try to read label+uuid */
+int volume_id_probe(struct volume_id *id, enum filesystem_type fs_type)
+{
+ int rc;
+
+ if (id == NULL)
+ return -EINVAL;
+
+ if (open_superblock(id) != 0)
+ return -EACCES;
+
+ switch (fs_type) {
+ case EXT3:
+ case EXT2:
+ rc = probe_ext(id);
+ break;
+ case REISER:
+ rc = probe_reiser(id);
+ break;
+ case XFS:
+ rc = probe_xfs(id);
+ break;
+ case JFS:
+ rc = probe_jfs(id);
+ break;
+ case MSDOS:
+ rc = probe_msdos(id);
+ break;
+ case VFAT:
+ rc = probe_vfat(id);
+ break;
+ case NTFS:
+ rc = probe_ntfs(id);
+ break;
+ case SWAP:
+ rc = probe_swap(id);
+ break;
+ default:
+ rc = probe_ext(id);
+ if (rc == 0)
+ break;
+ rc = probe_reiser(id);
+ if (rc == 0)
+ break;
+ rc = probe_xfs(id);
+ if (rc == 0)
+ break;
+ rc = probe_jfs(id);
+ if (rc == 0)
+ break;
+ rc = probe_msdos(id);
+ if (rc == 0)
+ break;
+ rc = probe_vfat(id);
+ if (rc == 0)
+ break;
+ rc = probe_ntfs(id);
+ if (rc == 0)
+ break;
+ rc = probe_swap(id);
+ if (rc == 0)
+ break;
+ rc = -1;
+ }
+
+ if (rc == 0)
+ close_superblock(id);
+
+ return rc;
+}
+
+/* open volume by already open file descriptor */
+struct volume_id *volume_id_open_fd(int fd)
+{
+ struct volume_id *id;
+
+ id = malloc(sizeof(struct volume_id));
+ if (id == NULL)
+ return NULL;
+ memset(id, 0x00, sizeof(struct volume_id));
+
+ id->fd = fd;
+
+ return id;
+}
+
+/* open volume by device node */
+struct volume_id *volume_id_open_node(const char *path)
+{
+ struct volume_id *id;
+ int fd;
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+
+ id = volume_id_open_fd(fd);
+ if (id == NULL)
+ return NULL;
+
+ /* close fd on device close */
+ id->fd_close = 1;
+
+ return id;
+}
+
+/* open volume by major/minor */
+struct volume_id *volume_id_open_dev_t(dev_t devt)
+{
+ struct volume_id *id;
+ char tmp_node[VOLUME_ID_PATH_MAX];
+
+ snprintf(tmp_node, VOLUME_ID_PATH_MAX,
+ "/tmp/volume-%u-%u", major(devt), minor(devt));
+ tmp_node[VOLUME_ID_PATH_MAX] = '\0';
+
+ /* create tempory node to open the block device */
+ if (mknod(tmp_node, (S_IFBLK | 0600), devt) != 0)
+ return NULL;
+
+ id = volume_id_open_node(tmp_node);
+
+ unlink(tmp_node);
+
+ return id;
+}
+
+/* free allocated volume info */
+void volume_id_close(struct volume_id *id)
+{
+ if (id == NULL)
+ return;
+
+ if (id->fd_close != 0)
+ close(id->fd);
+
+ close_superblock(id);
+
+ free(id);
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-21 23:15:45 +0000