extras/volume_id/volume_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 #include "sysv.h"
  30
  31 #define SYSV_NICINOD                    100
  32 #define SYSV_NICFREE                    50
  33
  34 struct sysv_super
  35 {
  36         uint16_t        s_isize;
  37         uint16_t        s_pad0;
  38         uint32_t        s_fsize;
  39         uint16_t        s_nfree;
  40         uint16_t        s_pad1;
  41         uint32_t        s_free[SYSV_NICFREE];
  42         uint16_t        s_ninode;
  43         uint16_t        s_pad2;
  44         uint16_t        s_inode[SYSV_NICINOD];
  45         uint8_t         s_flock;
  46         uint8_t         s_ilock;
  47         uint8_t         s_fmod;
  48         uint8_t         s_ronly;
  49         uint32_t        s_time;
  50         uint16_t        s_dinfo[4];
  51         uint32_t        s_tfree;
  52         uint16_t        s_tinode;
  53         uint16_t        s_pad3;
  54         uint8_t         s_fname[6];
  55         uint8_t         s_fpack[6];
  56         uint32_t        s_fill[12];
  57         uint32_t        s_state;
  58         uint32_t        s_magic;
  59         uint32_t        s_type;
  60 } __attribute__((__packed__));
  61
  62 #define XENIX_NICINOD                           100
  63 #define XENIX_NICFREE                           100
  64
  65 struct xenix_super {
  66         uint16_t        s_isize;
  67         uint32_t        s_fsize;
  68         uint16_t        s_nfree;
  69         uint32_t        s_free[XENIX_NICFREE];
  70         uint16_t        s_ninode;
  71         uint16_t        s_inode[XENIX_NICINOD];
  72         uint8_t         s_flock;
  73         uint8_t         s_ilock;
  74         uint8_t         s_fmod;
  75         uint8_t         s_ronly;
  76         uint32_t        s_time;
  77         uint32_t        s_tfree;
  78         uint16_t        s_tinode;
  79         uint16_t        s_dinfo[4];
  80         uint8_t         s_fname[6];
  81         uint8_t         s_fpack[6];
  82         uint8_t         s_clean;
  83         uint8_t         s_fill[371];
  84         uint32_t        s_magic;
  85         uint32_t        s_type;
  86 } __attribute__((__packed__));
  87
  88 #define SYSV_SUPERBLOCK_BLOCK                   0x01
  89 #define SYSV_MAGIC                              0xfd187e20
  90 #define XENIX_SUPERBLOCK_BLOCK                  0x18
  91 #define XENIX_MAGIC                             0x2b5544
  92 #define SYSV_MAX_BLOCKSIZE                      0x800
  93
  94 int volume_id_probe_sysv(struct volume_id *id, uint64_t off)
  95 {
  96         struct sysv_super *vs;
  97         struct xenix_super *xs;
  98         unsigned int boff;
  99
 100         dbg("probing at offset 0x%llx", (unsigned long long) off);
 101
 102         for (boff = 0x200; boff <= SYSV_MAX_BLOCKSIZE; boff <<= 1) {
 103                 vs = (struct sysv_super *)
 104                         volume_id_get_buffer(id, off + (boff * SYSV_SUPERBLOCK_BLOCK), 0x200);
 105                 if (vs == NULL)
 106                         return -1;
 107
 108                 if (vs->s_magic == cpu_to_le32(SYSV_MAGIC) || vs->s_magic == cpu_to_be32(SYSV_MAGIC)) {
 109                         volume_id_set_label_raw(id, vs->s_fname, 6);
 110                         volume_id_set_label_string(id, vs->s_fname, 6);
 111                         id->type = "sysv";
 112                         goto found;
 113                 }
 114         }
 115
 116         for (boff = 0x200; boff <= SYSV_MAX_BLOCKSIZE; boff <<= 1) {
 117                 xs = (struct xenix_super *)
 118                         volume_id_get_buffer(id, off + (boff + XENIX_SUPERBLOCK_BLOCK), 0x200);
 119                 if (xs == NULL)
 120                         return -1;
 121
 122                 if (xs->s_magic == cpu_to_le32(XENIX_MAGIC) || xs->s_magic == cpu_to_be32(XENIX_MAGIC)) {
 123                         volume_id_set_label_raw(id, xs->s_fname, 6);
 124                         volume_id_set_label_string(id, xs->s_fname, 6);
 125                         id->type = "xenix";
 126                         goto found;
 127                 }
 128         }
 129
 130         return -1;
 131
 132 found:
 133         volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 134         return 0;
 135 }