blob: 8bdf05f17e1b02b2fc2a4822a4afbdbad946997b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
/*! \mainpage Cryptsetup API
*
* <b>The</b> documentation covers public parts of cryptsetup API. In the following sections you'll find
* the examples that describe some features of cryptsetup API.
* For more info about libcryptsetup API versions see
* <a href="https://gitlab.com/cryptsetup/cryptsetup/wikis/ABI-tracker/timeline/libcryptsetup/index.html">API Tracker</a>.
*
* <OL type="A">
* <LI>@ref cexamples "Cryptsetup API examples"</LI>
* <OL type="1">
* <LI>@ref cluks "crypt_luks_usage" - cryptsetup LUKS device type usage examples</LI>
* <UL>
* <LI>@ref cinit "crypt_init()"</LI>
* <LI>@ref cformat "crypt_format()" - header and payload on mutual device</LI>
* <LI>@ref ckeys "Keyslot operations" </LI>
* <UL>
* <LI>@ref ckeyslot_vol "crypt_keyslot_add_by_volume_key()"</LI>
* <LI>@ref ckeyslot_pass "crypt_keyslot_add_by_passphrase()"</LI>
* </UL>
* <LI>@ref cload "crypt_load()"
* <LI>@ref cactivate "crypt_activate_by_passphrase()"</LI>
* <LI>@ref cactive_pars "crypt_get_active_device()"</LI>
* <LI>@ref cinit_by_name "crypt_init_by_name()"</LI>
* <LI>@ref cdeactivate "crypt_deactivate()"</LI>
* <LI>@ref cluks_ex "crypt_luks_usage.c"</LI>
* </UL>
* <LI>@ref clog "crypt_log_usage" - cryptsetup logging API examples</LI>
* </OL>
* </OL>
*
* @section cexamples Cryptsetup API examples
* @section cluks crypt_luks_usage - cryptsetup LUKS device type usage
* @subsection cinit crypt_init()
* Every time you need to do something with cryptsetup or dmcrypt device
* you need a valid context. The first step to start your work is
* @ref crypt_init call. You can call it either with path
* to the block device or path to the regular file. If you don't supply the path,
* empty context is initialized.
*
* @subsection cformat crypt_format() - header and payload on mutual device
* This section covers basic use cases for formatting LUKS devices. Format operation
* sets device type in context and in case of LUKS header is written at the beginning
* of block device. In the example below we use the scenario where LUKS header and data
* are both stored on the same device. There's also a possibility to store header and
* data separately.
*
* <B>Bear in mind</B> that @ref crypt_format() is destructive operation and it
* overwrites part of the backing block device.
*
* @subsection ckeys Keyslot operations examples
* After successful @ref crypt_format of LUKS device, volume key is not stored
* in a persistent way on the device. Keyslot area is an array beyond LUKS header, where
* volume key is stored in the encrypted form using user input passphrase. For more info about
* LUKS keyslots and how it's actually protected, please look at
* <A HREF="https://gitlab.com/cryptsetup/cryptsetup/wikis/Specification">LUKS specification</A>.
* There are two basic methods to create a new keyslot:
*
* @subsection ckeyslot_vol crypt_keyslot_add_by_volume_key()
* Creates a new keyslot directly by encrypting volume_key stored in the device
* context. Passphrase should be supplied or user is prompted if passphrase param is
* NULL.
*
* @subsection ckeyslot_pass crypt_keyslot_add_by_passphrase()
* Creates a new keyslot for the volume key by opening existing active keyslot,
* extracting volume key from it and storing it into a new keyslot
* protected by a new passphrase
*
* @subsection cload crypt_load()
* Function loads header from backing block device into device context.
*
* @subsection cactivate crypt_activate_by_passphrase()
* Activates crypt device by user supplied password for keyslot containing the volume_key.
* If <I>keyslot</I> parameter is set to <I>CRYPT_ANY_SLOT</I> then all active keyslots
* are tried one by one until the volume key is found.
*
* @subsection cactive_pars crypt_get_active_device()
* This call returns structure containing runtime attributes of active device.
*
* @subsection cinit_by_name crypt_init_by_name()
* In case you need to do operations with active device (device which already
* has its corresponding mapping) and you miss valid device context stored in
* *crypt_device reference, you should use this call. Function tries to
* get path to backing device from DM, initializes context for it and loads LUKS
* header.
*
* @subsection cdeactivate crypt_deactivate()
* Deactivates crypt device (removes DM mapping and safely erases volume key from kernel).
*
* @subsection cluks_ex crypt_luks_usage.c - Complex example
* To compile and run use following commands in examples directory:
*
* @code
* make
* ./crypt_luks_usage _path_to_[block_device]_file
* @endcode
* Note that you need to have the cryptsetup library compiled. @include crypt_luks_usage.c
*
* @section clog crypt_log_usage - cryptsetup logging API example
* Example describes basic use case for cryptsetup logging. To compile and run
* use following commands in examples directory:
*
* @code
* make
* ./crypt_log_usage
* @endcode
* Note that you need to have the cryptsetup library compiled. @include crypt_log_usage.c
*
* @example crypt_luks_usage.c
* @example crypt_log_usage.c
*/
|
