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
31 struct 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 */
54 struct 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
60 void dm_ima_reset_data(struct mapped_device *md);
61 void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags);
62 void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap);
63 void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all);
64 void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map);
65 void dm_ima_measure_on_device_rename(struct mapped_device *md);
66
67 #else
68
dm_ima_reset_data(struct mapped_device * md)69 static inline void dm_ima_reset_data(struct mapped_device *md) {}
dm_ima_measure_on_table_load(struct dm_table * table,unsigned int status_flags)70 static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
dm_ima_measure_on_device_resume(struct mapped_device * md,bool swap)71 static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
dm_ima_measure_on_device_remove(struct mapped_device * md,bool remove_all)72 static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
dm_ima_measure_on_table_clear(struct mapped_device * md,bool new_map)73 static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map) {}
dm_ima_measure_on_device_rename(struct mapped_device * md)74 static inline void dm_ima_measure_on_device_rename(struct mapped_device *md) {}
75
76 #endif /* CONFIG_IMA */
77
78 #endif /* DM_IMA_H */
79