1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2021 Microsoft Corporation
4 *
5 * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
6 *
7 * Header file for device mapper IMA measurements.
8 */
9
10#ifndef DM_IMA_H
11#define DM_IMA_H
12
13#define DM_IMA_MEASUREMENT_BUF_LEN 4096
14#define DM_IMA_DEVICE_BUF_LEN 1024
15#define DM_IMA_TARGET_METADATA_BUF_LEN 128
16#define DM_IMA_TARGET_DATA_BUF_LEN 2048
17#define DM_IMA_DEVICE_CAPACITY_BUF_LEN 128
18#define DM_IMA_TABLE_HASH_ALG "sha256"
19
20#define __dm_ima_stringify(s) #s
21#define __dm_ima_str(s) __dm_ima_stringify(s)
22
23#define DM_IMA_VERSION_STR "dm_version=" \
24 __dm_ima_str(DM_VERSION_MAJOR) "." \
25 __dm_ima_str(DM_VERSION_MINOR) "." \
26 __dm_ima_str(DM_VERSION_PATCHLEVEL) ";"
27
28#ifdef CONFIG_IMA
29
30struct dm_ima_device_table_metadata {
31 /*
32 * Contains data specific to the device which is common across
33 * all the targets in the table (e.g. name, uuid, major, minor, etc).
34 * The values are stored in comma separated list of key1=val1,key2=val2;
35 * pairs delimited by a semicolon at the end of the list.
36 */
37 char *device_metadata;
38 unsigned int device_metadata_len;
39 unsigned int num_targets;
40
41 /*
42 * Contains the sha256 hashes of the IMA measurements of the target
43 * attributes' key-value pairs from the active/inactive tables.
44 */
45 char *hash;
46 unsigned int hash_len;
47};
48
49/*
50 * This structure contains device metadata, and table hash for
51 * active and inactive tables for ima measurements.
52 */
53struct dm_ima_measurements {
54 struct dm_ima_device_table_metadata active_table;
55 struct dm_ima_device_table_metadata inactive_table;
56 unsigned int dm_version_str_len;
57};
58
59void dm_ima_reset_data(struct mapped_device *md);
60void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
61void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
62void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all);
63void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map);
64void dm_ima_measure_on_device_rename(struct mapped_device *md);
65
66#else
67
68static inline void dm_ima_reset_data(struct mapped_device *md) {}
69static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
70static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
71static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
72static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map) {}
73static inline void dm_ima_measure_on_device_rename(struct mapped_device *md) {}
74
75#endif /* CONFIG_IMA */
76
77#endif /* DM_IMA_H */
78