plugins/linuxdisk/virtual-disk.c

   1 /* nbdkit
   2  * Copyright Red Hat
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  * * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * * Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  *
  15  * * Neither the name of Red Hat nor the names of its contributors may be
  16  * used to endorse or promote products derived from this software without
  17  * specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  21  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  22  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
  23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  26  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  27  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <config.h>
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <stdbool.h>
  38 #include <stdint.h>
  39 #include <inttypes.h>
  40 #include <string.h>
  41 #include <unistd.h>
  42
  43 #include <nbdkit-plugin.h>
  44
  45 #include "random.h"
  46 #include "regions.h"
  47
  48 #include "virtual-disk.h"
  49
  50 static int create_regions (struct virtual_disk *disk);
  51
  52 void
  53 init_virtual_disk (struct virtual_disk *disk)
  54 {
  55   memset (disk, 0, sizeof *disk);
  56   disk->fd = -1;
  57
  58   init_regions (&disk->regions);
  59 }
  60
  61 int
  62 create_virtual_disk (struct virtual_disk *disk)
  63 {
  64   size_t i;
  65
  66   /* Allocate the partition table structures.  We can't fill them in
  67    * until we have created the disk layout.
  68    */
  69   disk->protective_mbr = calloc (1, SECTOR_SIZE);
  70   disk->primary_header = calloc (1, SECTOR_SIZE);
  71   disk->pt = calloc (1, 32*SECTOR_SIZE);
  72   disk->secondary_header = calloc (1, SECTOR_SIZE);
  73   if (disk->protective_mbr == NULL ||
  74       disk->primary_header == NULL ||
  75       disk->pt == NULL ||
  76       disk->secondary_header == NULL) {
  77     nbdkit_error ("calloc: %m");
  78     return -1;
  79   }
  80
  81   /* Create the filesystem.  This fills in disk->filesystem_size and
  82    * disk->id.
  83    */
  84   if (create_filesystem (disk) == -1)
  85     return -1;
  86
  87   /* Create a random GUID used as "Unique partition GUID".  However
  88    * this doesn't follow GUID conventions so in theory could make an
  89    * invalid value.
  90    */
  91   for (i = 0; i < 16; ++i)
  92     disk->guid[i] = xrandom (&random_state) & 0xff;
  93
  94   /* Create the virtual disk regions. */
  95   if (create_regions (disk) == -1)
  96     return -1;
  97
  98   /* Initialize partition table structures.  This depends on
  99    * disk->regions so must be done last.
 100    */
 101   if (create_partition_table (disk) == -1)
 102     return -1;
 103
 104   return 0;
 105 }
 106
 107 void
 108 free_virtual_disk (struct virtual_disk *disk)
 109 {
 110   free_regions (&disk->regions);
 111   free (disk->protective_mbr);
 112   free (disk->primary_header);
 113   free (disk->pt);
 114   free (disk->secondary_header);
 115   if (disk->fd >= 0)
 116     close (disk->fd);
 117 }
 118
 119 /* Lay out the final disk. */
 120 static int
 121 create_regions (struct virtual_disk *disk)
 122 {
 123   /* Protective MBR. */
 124   if (append_region_len (&disk->regions, "Protective MBR",
 125                          SECTOR_SIZE, 0, 0,
 126                          region_data, (void *) disk->protective_mbr) == -1)
 127     return -1;
 128
 129   /* GPT primary partition table header (LBA 1). */
 130   if (append_region_len (&disk->regions, "GPT primary header",
 131                          SECTOR_SIZE, 0, 0,
 132                          region_data, (void *) disk->primary_header) == -1)
 133     return -1;
 134
 135   /* GPT primary PT (LBA 2..33). */
 136   if (append_region_len (&disk->regions, "GPT primary PT",
 137                          32*SECTOR_SIZE, 0, 0,
 138                          region_data, (void *) disk->pt) == -1)
 139     return -1;
 140
 141   /* Partition containing the filesystem.  Align it to 2048 sectors. */
 142   if (append_region_len (&disk->regions, "Filesystem",
 143                          disk->filesystem_size, 2048*SECTOR_SIZE, 0,
 144                          region_file, 0 /* unused */) == -1)
 145     return -1;
 146
 147   /* GPT secondary PT (LBA -33..-2). */
 148   if (append_region_len (&disk->regions, "GPT secondary PT",
 149                          32*SECTOR_SIZE, SECTOR_SIZE, 0,
 150                          region_data, (void *) disk->pt) == -1)
 151     return -1;
 152
 153   /* GPT secondary PT header (LBA -1). */
 154   if (append_region_len (&disk->regions, "GPT secondary header",
 155                          SECTOR_SIZE, 0, 0,
 156                          region_data, (void *) disk->secondary_header) == -1)
 157     return -1;
 158
 159   return 0;
 160 }