drivers/md/dm-ima.h

   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
  69 static inline void dm_ima_reset_data(struct mapped_device *md) {}
  70 static inline void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags) {}
  71 static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap) {}
  72 static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all) {}
  73 static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map) {}
  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 */