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Diffstat (limited to 'drivers/md/dm-ima.h')
| -rw-r--r-- | drivers/md/dm-ima.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/drivers/md/dm-ima.h b/drivers/md/dm-ima.h new file mode 100644 index 000000000..0ec013d15 --- /dev/null +++ b/drivers/md/dm-ima.h @@ -0,0 +1,118 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2021 Microsoft Corporation + * + * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com> + * + * Header file for device mapper IMA measurements. + */ + +#ifndef DM_IMA_H +#define DM_IMA_H + +#define DM_IMA_MEASUREMENT_BUF_LEN 4096 +#define DM_IMA_DEVICE_BUF_LEN 1024 +#define DM_IMA_TARGET_METADATA_BUF_LEN 128 +#define DM_IMA_TARGET_DATA_BUF_LEN 2048 +#define DM_IMA_DEVICE_CAPACITY_BUF_LEN 128 + +#define __dm_ima_stringify(s) #s +#define __dm_ima_str(s) __dm_ima_stringify(s) + +#define DM_IMA_VERSION_STR "dm_version=" \ + __dm_ima_str(DM_VERSION_MAJOR) "." \ + __dm_ima_str(DM_VERSION_MINOR) "." \ + __dm_ima_str(DM_VERSION_PATCHLEVEL) ";" + +enum dm_ima_table_op { + DM_IMA_TABLE_SAVE, + DM_IMA_TABLE_RESTORE, +}; + +#ifdef CONFIG_IMA + +struct dm_ima_device_table_metadata { + /* + * Contains data specific to the device which is common across + * all the targets in the table (e.g. name, uuid, major, minor, etc). + * The values are stored in comma separated list of key1=val1,key2=val2; + * pairs delimited by a semicolon at the end of the list. + */ + char *device_metadata; + unsigned int device_metadata_len; + unsigned int num_targets; + sector_t capacity; + + /* + * Contains the sha256 hashes of the IMA measurements of the target + * attributes' key-value pairs from the active/inactive tables. + */ + char *hash; + unsigned int hash_len; +}; + +struct dm_ima_context { + struct dm_ima_device_table_metadata table; + unsigned int update_idx; + char dev_name[DM_NAME_LEN*2]; + char dev_uuid[DM_UUID_LEN*2]; +}; + +/* + * This structure contains device metadata, and table hash for + * active and inactive tables for ima measurements. + */ +struct dm_ima_measurements { + unsigned int update_idx; + unsigned int measure_idx; + struct wait_queue_head ima_wq; + spinlock_t ima_lock; + struct dm_ima_device_table_metadata active_table; + struct dm_ima_device_table_metadata inactive_table; +}; + +void dm_ima_init(struct mapped_device *md); +void dm_ima_alloc_context(struct dm_ima_context **context, bool noio); +void dm_ima_free_context(struct dm_ima_context *context); +void dm_ima_context_table_op(struct mapped_device *md, + struct dm_ima_context *context, + enum dm_ima_table_op op); +void dm_ima_measure_on_table_load(struct dm_table *table, + struct dm_ima_context *context); +void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap, + struct dm_ima_context *context); +void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all, + struct dm_ima_context *context, + unsigned int idx); +void dm_ima_measure_on_table_clear(struct mapped_device *md, + struct dm_ima_context *context); +void dm_ima_measure_on_device_rename(struct mapped_device *md, + struct dm_ima_context *context); + +#else + +struct dm_ima_context; + +static inline void dm_ima_init(struct mapped_device *md) {} +static inline void dm_ima_alloc_context(struct dm_ima_context **context, bool noio) {} +static inline void dm_ima_free_context(struct dm_ima_context *context) {} +static inline void dm_ima_context_table_op(struct mapped_device *md, + struct dm_ima_context *context, + enum dm_ima_table_op op) {} +static inline void dm_ima_measure_on_table_load(struct dm_table *table, + struct dm_ima_context *context) {} +static inline void dm_ima_measure_on_device_resume(struct mapped_device *md, + bool swap, + struct dm_ima_context *context) {} +static inline void dm_ima_measure_on_device_remove(struct mapped_device *md, + bool remove_all, + struct dm_ima_context *context, + unsigned int idx) {} +static inline void dm_ima_measure_on_table_clear(struct mapped_device *md, + struct dm_ima_context *context) {} +static inline void dm_ima_measure_on_device_rename(struct mapped_device *md, + struct dm_ima_context *context) {} + +#endif /* CONFIG_IMA */ + +#endif /* DM_IMA_H */ |