extras/volume_id/libvolume_id/sysv.c

   1 /*
   2  * volume_id - reads filesystem label and uuid
   3  *
   4  * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  *      This program is free software; you can redistribute it and/or modify it
   7  *      under the terms of the GNU General Public License as published by the
   8  *      Free Software Foundation version 2 of the License.
   9  */
  10
  11 #ifndef _GNU_SOURCE
  12 #define _GNU_SOURCE 1
  13 #endif
  14
  15 #ifdef HAVE_CONFIG_H
  16 #  include <config.h>
  17 #endif
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <string.h>
  23 #include <errno.h>
  24 #include <ctype.h>
  25
  26 #include "volume_id.h"
  27 #include "logging.h"
  28 #include "util.h"
  29
  30 #define SYSV_NICINOD                    100
  31 #define SYSV_NICFREE                    50
  32
  33 struct sysv_super
  34 {
  35         uint16_t        s_isize;
  36         uint16_t        s_pad0;
  37         uint32_t        s_fsize;
  38         uint16_t        s_nfree;
  39         uint16_t        s_pad1;
  40         uint32_t        s_free[SYSV_NICFREE];
  41         uint16_t        s_ninode;
  42         uint16_t        s_pad2;
  43         uint16_t        s_inode[SYSV_NICINOD];
  44         uint8_t         s_flock;
  45         uint8_t         s_ilock;
  46         uint8_t         s_fmod;
  47         uint8_t         s_ronly;
  48         uint32_t        s_time;
  49         uint16_t        s_dinfo[4];
  50         uint32_t        s_tfree;
  51         uint16_t        s_tinode;
  52         uint16_t        s_pad3;
  53         uint8_t         s_fname[6];
  54         uint8_t         s_fpack[6];
  55         uint32_t        s_fill[12];
  56         uint32_t        s_state;
  57         uint32_t        s_magic;
  58         uint32_t        s_type;
  59 } PACKED;
  60
  61 #define XENIX_NICINOD                           100
  62 #define XENIX_NICFREE                           100
  63
  64 struct xenix_super {
  65         uint16_t        s_isize;
  66         uint32_t        s_fsize;
  67         uint16_t        s_nfree;
  68         uint32_t        s_free[XENIX_NICFREE];
  69         uint16_t        s_ninode;
  70         uint16_t        s_inode[XENIX_NICINOD];
  71         uint8_t         s_flock;
  72         uint8_t         s_ilock;
  73         uint8_t         s_fmod;
  74         uint8_t         s_ronly;
  75         uint32_t        s_time;
  76         uint32_t        s_tfree;
  77         uint16_t        s_tinode;
  78         uint16_t        s_dinfo[4];
  79         uint8_t         s_fname[6];
  80         uint8_t         s_fpack[6];
  81         uint8_t         s_clean;
  82         uint8_t         s_fill[371];
  83         uint32_t        s_magic;
  84         uint32_t        s_type;
  85 } PACKED;
  86
  87 #define SYSV_SUPERBLOCK_BLOCK                   0x01
  88 #define SYSV_MAGIC                              0xfd187e20
  89 #define XENIX_SUPERBLOCK_BLOCK                  0x18
  90 #define XENIX_MAGIC                             0x2b5544
  91 #define SYSV_MAX_BLOCKSIZE                      0x800
  92
  93 int volume_id_probe_sysv(struct volume_id *id, uint64_t off)
  94 {
  95         struct sysv_super *vs;
  96         struct xenix_super *xs;
  97         unsigned int boff;
  98
  99         dbg("probing at offset 0x%llx", (unsigned long long) off);
 100
 101         for (boff = 0x200; boff <= SYSV_MAX_BLOCKSIZE; boff <<= 1) {
 102                 vs = (struct sysv_super *)
 103                         volume_id_get_buffer(id, off + (boff * SYSV_SUPERBLOCK_BLOCK), 0x200);
 104                 if (vs == NULL)
 105                         return -1;
 106
 107                 if (vs->s_magic == cpu_to_le32(SYSV_MAGIC) || vs->s_magic == cpu_to_be32(SYSV_MAGIC)) {
 108                         volume_id_set_label_raw(id, vs->s_fname, 6);
 109                         volume_id_set_label_string(id, vs->s_fname, 6);
 110                         id->type = "sysv";
 111                         goto found;
 112                 }
 113         }
 114
 115         for (boff = 0x200; boff <= SYSV_MAX_BLOCKSIZE; boff <<= 1) {
 116                 xs = (struct xenix_super *)
 117                         volume_id_get_buffer(id, off + (boff + XENIX_SUPERBLOCK_BLOCK), 0x200);
 118                 if (xs == NULL)
 119                         return -1;
 120
 121                 if (xs->s_magic == cpu_to_le32(XENIX_MAGIC) || xs->s_magic == cpu_to_be32(XENIX_MAGIC)) {
 122                         volume_id_set_label_raw(id, xs->s_fname, 6);
 123                         volume_id_set_label_string(id, xs->s_fname, 6);
 124                         id->type = "xenix";
 125                         goto found;
 126                 }
 127         }
 128
 129         return -1;
 130
 131 found:
 132         volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 133         return 0;
 134 }