drivers/md/dm-ima.h

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