LXR busybox/util-linux/volume

   1/*
   2 * volume_id - reads filesystem label and uuid
   3 *
   4 * Copyright (C) 2005 W. Michael Petullo <mike@flyn.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//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_LUKS) += luks.o
  22
  23//config:
  24//config:config FEATURE_VOLUMEID_LUKS
  25//config:       bool "luks filesystem"
  26//config:       default y
  27//config:       depends on VOLUMEID
  28//config:       help
  29//config:         TODO
  30//config:
  31
  32#include "volume_id_internal.h"
  33
  34#define LUKS_MAGIC_L             6
  35#define UUID_STRING_L           40
  36#define LUKS_CIPHERNAME_L       32
  37#define LUKS_CIPHERMODE_L       32
  38#define LUKS_HASHSPEC_L         32
  39#define LUKS_DIGESTSIZE         20
  40#define LUKS_SALTSIZE           32
  41#define LUKS_NUMKEYS             8
  42
  43static const uint8_t LUKS_MAGIC[] = { 'L','U','K','S', 0xba, 0xbe };
  44
  45struct luks_phdr {
  46        uint8_t         magic[LUKS_MAGIC_L];
  47        uint16_t        version;
  48        uint8_t         cipherName[LUKS_CIPHERNAME_L];
  49        uint8_t         cipherMode[LUKS_CIPHERMODE_L];
  50        uint8_t         hashSpec[LUKS_HASHSPEC_L];
  51        uint32_t        payloadOffset;
  52        uint32_t        keyBytes;
  53        uint8_t         mkDigest[LUKS_DIGESTSIZE];
  54        uint8_t         mkDigestSalt[LUKS_SALTSIZE];
  55        uint32_t        mkDigestIterations;
  56        uint8_t         uuid[UUID_STRING_L];
  57        struct {
  58                uint32_t        active;
  59                uint32_t        passwordIterations;
  60                uint8_t         passwordSalt[LUKS_SALTSIZE];
  61                uint32_t        keyMaterialOffset;
  62                uint32_t        stripes;
  63        } keyblock[LUKS_NUMKEYS];
  64};
  65
  66enum {
  67        EXPECTED_SIZE_luks_phdr = 0
  68                + 1 * LUKS_MAGIC_L
  69                + 2
  70                + 1 * LUKS_CIPHERNAME_L
  71                + 1 * LUKS_CIPHERMODE_L
  72                + 1 * LUKS_HASHSPEC_L
  73                + 4
  74                + 4
  75                + 1 * LUKS_DIGESTSIZE
  76                + 1 * LUKS_SALTSIZE
  77                + 4
  78                + 1 * UUID_STRING_L
  79                + LUKS_NUMKEYS * (0
  80                  + 4
  81                  + 4
  82                  + 1 * LUKS_SALTSIZE
  83                  + 4
  84                  + 4
  85                  )
  86};
  87
  88struct BUG_bad_size_luks_phdr {
  89        char BUG_bad_size_luks_phdr[
  90                sizeof(struct luks_phdr) == EXPECTED_SIZE_luks_phdr ?
  91                1 : -1];
  92};
  93
  94int FAST_FUNC volume_id_probe_luks(struct volume_id *id /*,uint64_t off*/)
  95{
  96#define off ((uint64_t)0)
  97        struct luks_phdr *header;
  98
  99        header = volume_id_get_buffer(id, off, sizeof(*header));
 100        if (header == NULL)
 101                return -1;
 102
 103        if (memcmp(header->magic, LUKS_MAGIC, LUKS_MAGIC_L))
 104                return -1;
 105
 106//      volume_id_set_usage(id, VOLUME_ID_CRYPTO);
 107        volume_id_set_uuid(id, header->uuid, UUID_DCE_STRING);
 108        IF_FEATURE_BLKID_TYPE(id->type = "crypto_LUKS";)
 109
 110        return 0;
 111}
 112