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 //config:config FEATURE_VOLUMEID_LUKS
21 //config: bool "luks filesystem"
22 //config: default y
23 //config: depends on VOLUMEID
24
25 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_LUKS) += luks.o
26
27 #include "volume_id_internal.h"
28
29 #define LUKS_MAGIC_L 6
30 #define UUID_STRING_L 40
31 #define LUKS_CIPHERNAME_L 32
32 #define LUKS_CIPHERMODE_L 32
33 #define LUKS_HASHSPEC_L 32
34 #define LUKS_DIGESTSIZE 20
35 #define LUKS_SALTSIZE 32
36 #define LUKS_NUMKEYS 8
37
38 static const uint8_t LUKS_MAGIC[] ALIGN1 = { 'L','U','K','S', 0xba, 0xbe };
39
40 struct luks_phdr {
41 uint8_t magic[LUKS_MAGIC_L];
42 uint16_t version;
43 uint8_t cipherName[LUKS_CIPHERNAME_L];
44 uint8_t cipherMode[LUKS_CIPHERMODE_L];
45 uint8_t hashSpec[LUKS_HASHSPEC_L];
46 uint32_t payloadOffset;
47 uint32_t keyBytes;
48 uint8_t mkDigest[LUKS_DIGESTSIZE];
49 uint8_t mkDigestSalt[LUKS_SALTSIZE];
50 uint32_t mkDigestIterations;
51 uint8_t uuid[UUID_STRING_L];
52 struct {
53 uint32_t active;
54 uint32_t passwordIterations;
55 uint8_t passwordSalt[LUKS_SALTSIZE];
56 uint32_t keyMaterialOffset;
57 uint32_t stripes;
58 } keyblock[LUKS_NUMKEYS];
59 };
60
61 enum {
62 EXPECTED_SIZE_luks_phdr = 0
63 + 1 * LUKS_MAGIC_L
64 + 2
65 + 1 * LUKS_CIPHERNAME_L
66 + 1 * LUKS_CIPHERMODE_L
67 + 1 * LUKS_HASHSPEC_L
68 + 4
69 + 4
70 + 1 * LUKS_DIGESTSIZE
71 + 1 * LUKS_SALTSIZE
72 + 4
73 + 1 * UUID_STRING_L
74 + LUKS_NUMKEYS * (0
75 + 4
76 + 4
77 + 1 * LUKS_SALTSIZE
78 + 4
79 + 4
80 )
81 };
82
83 struct BUG_bad_size_luks_phdr {
84 char BUG_bad_size_luks_phdr[
85 sizeof(struct luks_phdr) == EXPECTED_SIZE_luks_phdr ?
86 1 : -1];
87 };
88
volume_id_probe_luks(struct volume_id * id)89 int FAST_FUNC volume_id_probe_luks(struct volume_id *id /*,uint64_t off*/)
90 {
91 #define off ((uint64_t)0)
92 struct luks_phdr *header;
93
94 header = volume_id_get_buffer(id, off, sizeof(*header));
95 if (header == NULL)
96 return -1;
97
98 if (memcmp(header->magic, LUKS_MAGIC, LUKS_MAGIC_L))
99 return -1;
100
101 // volume_id_set_usage(id, VOLUME_ID_CRYPTO);
102 volume_id_set_uuid(id, header->uuid, UUID_DCE_STRING);
103 IF_FEATURE_BLKID_TYPE(id->type = "crypto_LUKS";)
104
105 return 0;
106 }
107