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