libblkid/src/superblocks/via_raid.c

   1 /*
   2  * Copyright (C) 2008 Karel Zak <kzak@redhat.com>
   3  *
   4  * Inspired by libvolume_id by
   5  *     Kay Sievers <kay.sievers@vrfy.org>
   6  *
   7  * This file may be redistributed under the terms of the
   8  * GNU Lesser General Public License.
   9  */
  10
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <unistd.h>
  14 #include <string.h>
  15 #include <errno.h>
  16 #include <ctype.h>
  17 #include <stdint.h>
  18
  19 #include "superblocks.h"
  20
  21 struct via_metadata {
  22         uint16_t        signature;
  23         uint8_t         version_number;
  24         struct via_array {
  25                 uint16_t        disk_bit_mask;
  26                 uint8_t         disk_array_ex;
  27                 uint32_t        capacity_low;
  28                 uint32_t        capacity_high;
  29                 uint32_t        serial_checksum;
  30         } __attribute__((packed)) array;
  31         uint32_t        serial_checksum[8];
  32         uint8_t         checksum;
  33 } __attribute__((packed));
  34
  35 #define VIA_SIGNATURE           0xAA55
  36
  37 /* 8 bit checksum on first 50 bytes of metadata. */
  38 static uint8_t via_checksum(struct via_metadata *v)
  39 {
  40         uint8_t i = 50, cs = 0;
  41
  42         while (i--)
  43                 cs += ((uint8_t*) v)[i];
  44
  45         return cs == v->checksum;
  46 }
  47
  48 static int probe_viaraid(blkid_probe pr,
  49                 const struct blkid_idmag *mag __attribute__((__unused__)))
  50 {
  51         uint64_t off;
  52         struct via_metadata *v;
  53
  54         if (pr->size < 0x10000)
  55                 return -1;
  56         if (!S_ISREG(pr->mode) && !blkid_probe_is_wholedisk(pr))
  57                 return -1;
  58
  59         off = ((pr->size / 0x200)-1) * 0x200;
  60
  61         v = (struct via_metadata *)
  62                         blkid_probe_get_buffer(pr,
  63                                 off,
  64                                 sizeof(struct via_metadata));
  65         if (!v)
  66                 return -1;
  67         if (le16_to_cpu(v->signature) != VIA_SIGNATURE)
  68                 return -1;
  69         if (v->version_number > 2)
  70                 return -1;
  71         if (!via_checksum(v))
  72                 return -1;
  73         if (blkid_probe_sprintf_version(pr, "%u", v->version_number) != 0)
  74                 return -1;
  75         if (blkid_probe_set_magic(pr, off,
  76                                 sizeof(v->signature),
  77                                 (unsigned char *) &v->signature))
  78                 return -1;
  79         return 0;
  80 }
  81
  82 const struct blkid_idinfo viaraid_idinfo = {
  83         .name           = "via_raid_member",
  84         .usage          = BLKID_USAGE_RAID,
  85         .probefunc      = probe_viaraid,
  86         .magics         = BLKID_NONE_MAGIC
  87 };
  88
  89