shlibs/blkid/src/probers/luks.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 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <string.h>
  14 #include <errno.h>
  15 #include <ctype.h>
  16 #include <stdint.h>
  17
  18 #include "blkidP.h"
  19
  20 #define LUKS_CIPHERNAME_L               32
  21 #define LUKS_CIPHERMODE_L               32
  22 #define LUKS_HASHSPEC_L                 32
  23 #define LUKS_DIGESTSIZE                 20
  24 #define LUKS_SALTSIZE                   32
  25 #define LUKS_MAGIC_L                    6
  26 #define UUID_STRING_L                   40
  27
  28 struct luks_phdr {
  29         uint8_t         magic[LUKS_MAGIC_L];
  30         uint16_t        version;
  31         uint8_t         cipherName[LUKS_CIPHERNAME_L];
  32         uint8_t         cipherMode[LUKS_CIPHERMODE_L];
  33         uint8_t         hashSpec[LUKS_HASHSPEC_L];
  34         uint32_t        payloadOffset;
  35         uint32_t        keyBytes;
  36         uint8_t         mkDigest[LUKS_DIGESTSIZE];
  37         uint8_t         mkDigestSalt[LUKS_SALTSIZE];
  38         uint32_t        mkDigestIterations;
  39         uint8_t         uuid[UUID_STRING_L];
  40 } __attribute__((packed));
  41
  42 static int probe_luks(blkid_probe pr, const struct blkid_idmag *mag)
  43 {
  44         struct luks_phdr *header;
  45
  46         header = blkid_probe_get_sb(pr, mag, struct luks_phdr);
  47         if (header == NULL)
  48                 return -1;
  49
  50         blkid_probe_strncpy_uuid(pr, (unsigned char *) header->uuid,
  51                         sizeof(header->uuid));
  52         blkid_probe_sprintf_version(pr, "%u", le16_to_cpu(header->version));
  53         return 0;
  54 }
  55
  56 const struct blkid_idinfo luks_idinfo =
  57 {
  58         .name           = "crypto_LUKS",
  59         .usage          = BLKID_USAGE_CRYPTO,
  60         .probefunc      = probe_luks,
  61         .magics         =
  62         {
  63                 { .magic = "LUKS\xba\xbe", .len = 6 },
  64                 { NULL }
  65         }
  66 };