extras/volume_id/volume_id/mac.c

   1 /*
   2  * volume_id - reads filesystem label and uuid
   3  *
   4  * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  *      This library is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU Lesser General Public
   8  *      License as published by the Free Software Foundation; either
   9  *      version 2.1 of the License, or (at your option) any later version.
  10  *
  11  *      This library is distributed in the hope that it will be useful,
  12  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  *      Lesser General Public License for more details.
  15  *
  16  *      You should have received a copy of the GNU Lesser General Public
  17  *      License along with this library; if not, write to the Free Software
  18  *      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  */
  20
  21 #ifndef _GNU_SOURCE
  22 #define _GNU_SOURCE 1
  23 #endif
  24
  25 #ifdef HAVE_CONFIG_H
  26 #  include <config.h>
  27 #endif
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <string.h>
  33 #include <errno.h>
  34 #include <ctype.h>
  35
  36 #include "volume_id.h"
  37 #include "logging.h"
  38 #include "util.h"
  39 #include "mac.h"
  40
  41 struct mac_driver_desc {
  42         uint8_t         signature[2];
  43         uint16_t        block_size;
  44         uint32_t        block_count;
  45 } __attribute__((__packed__));
  46
  47 struct mac_partition {
  48         uint8_t         signature[2];
  49         uint16_t        res1;
  50         uint32_t        map_count;
  51         uint32_t        start_block;
  52         uint32_t        block_count;
  53         uint8_t         name[32];
  54         uint8_t         type[32];
  55 } __attribute__((__packed__));
  56
  57 int volume_id_probe_mac_partition_map(struct volume_id *id, uint64_t off)
  58 {
  59         const uint8_t *buf;
  60         struct mac_driver_desc *driver;
  61         struct mac_partition *part;
  62
  63         dbg("probing at offset 0x%llx", (unsigned long long) off);
  64
  65         buf = volume_id_get_buffer(id, off, 0x200);
  66         if (buf == NULL)
  67                 return -1;
  68
  69         part = (struct mac_partition *) buf;
  70         if ((memcmp(part->signature, "PM", 2) == 0) &&
  71             (memcmp(part->type, "Apple_partition_map", 19) == 0)) {
  72                 /* linux creates an own subdevice for the map
  73                  * just return the type if the drive header is missing */
  74                 volume_id_set_usage(id, VOLUME_ID_PARTITIONTABLE);
  75                 id->type = "mac_partition_map";
  76                 return 0;
  77         }
  78
  79         driver = (struct mac_driver_desc *) buf;
  80         if (memcmp(driver->signature, "ER", 2) == 0) {
  81                 /* we are on a main device, like a CD
  82                  * just try to probe the first partition from the map */
  83                 unsigned int bsize = be16_to_cpu(driver->block_size);
  84                 int part_count;
  85                 int i;
  86
  87                 /* get first entry of partition table */
  88                 buf = volume_id_get_buffer(id, off +  bsize, 0x200);
  89                 if (buf == NULL)
  90                         return -1;
  91
  92                 part = (struct mac_partition *) buf;
  93                 if (memcmp(part->signature, "PM", 2) != 0)
  94                         return -1;
  95
  96                 part_count = be32_to_cpu(part->map_count);
  97                 dbg("expecting %d partition entries", part_count);
  98
  99                 if (id->partitions != NULL)
 100                         free(id->partitions);
 101                 id->partitions =
 102                         malloc(part_count * sizeof(struct volume_id_partition));
 103                 if (id->partitions == NULL)
 104                         return -1;
 105                 memset(id->partitions, 0x00, sizeof(struct volume_id_partition));
 106
 107                 id->partition_count = part_count;
 108
 109                 for (i = 0; i < part_count; i++) {
 110                         uint64_t poff;
 111                         uint64_t plen;
 112
 113                         buf = volume_id_get_buffer(id, off + ((i+1) * bsize), 0x200);
 114                         if (buf == NULL)
 115                                 return -1;
 116
 117                         part = (struct mac_partition *) buf;
 118                         if (memcmp(part->signature, "PM", 2) != 0)
 119                                 return -1;
 120
 121                         poff = be32_to_cpu(part->start_block) * bsize;
 122                         plen = be32_to_cpu(part->block_count) * bsize;
 123                         dbg("found '%s' partition entry at 0x%llx, len 0x%llx",
 124                             part->type, (unsigned long long) poff, (unsigned long long) plen);
 125
 126                         id->partitions[i].off = poff;
 127                         id->partitions[i].len = plen;
 128
 129                         if (memcmp(part->type, "Apple_Free", 10) == 0) {
 130                                 volume_id_set_usage_part(&id->partitions[i], VOLUME_ID_UNUSED);
 131                         } else if (memcmp(part->type, "Apple_partition_map", 19) == 0) {
 132                                 volume_id_set_usage_part(&id->partitions[i], VOLUME_ID_PARTITIONTABLE);
 133                         } else {
 134                                 volume_id_set_usage_part(&id->partitions[i], VOLUME_ID_UNPROBED);
 135                         }
 136                 }
 137                 volume_id_set_usage(id, VOLUME_ID_PARTITIONTABLE);
 138                 id->type = "mac_partition_map";
 139                 return 0;
 140         }
 141
 142         return -1;
 143 }