156 lines
5.3 KiB
C
156 lines
5.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Copyright 2019 Google LLC
|
|
*/
|
|
|
|
#ifndef __LINUX_BLK_CRYPTO_PROFILE_H
|
|
#define __LINUX_BLK_CRYPTO_PROFILE_H
|
|
|
|
#include <linux/bio.h>
|
|
#include <linux/blk-crypto.h>
|
|
|
|
struct blk_crypto_profile;
|
|
|
|
/**
|
|
* struct blk_crypto_ll_ops - functions to control inline encryption hardware
|
|
*
|
|
* Low-level operations for controlling inline encryption hardware. This
|
|
* interface must be implemented by storage drivers that support inline
|
|
* encryption. All functions may sleep, are serialized by profile->lock, and
|
|
* are never called while profile->dev (if set) is runtime-suspended.
|
|
*/
|
|
struct blk_crypto_ll_ops {
|
|
|
|
/**
|
|
* @keyslot_program: Program a key into the inline encryption hardware.
|
|
*
|
|
* Program @key into the specified @slot in the inline encryption
|
|
* hardware, overwriting any key that the keyslot may already contain.
|
|
* The keyslot is guaranteed to not be in-use by any I/O.
|
|
*
|
|
* This is required if the device has keyslots. Otherwise (i.e. if the
|
|
* device is a layered device, or if the device is real hardware that
|
|
* simply doesn't have the concept of keyslots) it is never called.
|
|
*
|
|
* Must return 0 on success, or -errno on failure.
|
|
*/
|
|
int (*keyslot_program)(struct blk_crypto_profile *profile,
|
|
const struct blk_crypto_key *key,
|
|
unsigned int slot);
|
|
|
|
/**
|
|
* @keyslot_evict: Evict a key from the inline encryption hardware.
|
|
*
|
|
* If the device has keyslots, this function must evict the key from the
|
|
* specified @slot. The slot will contain @key, but there should be no
|
|
* need for the @key argument to be used as @slot should be sufficient.
|
|
* The keyslot is guaranteed to not be in-use by any I/O.
|
|
*
|
|
* If the device doesn't have keyslots itself, this function must evict
|
|
* @key from any underlying devices. @slot won't be valid in this case.
|
|
*
|
|
* If there are no keyslots and no underlying devices, this function
|
|
* isn't required.
|
|
*
|
|
* Must return 0 on success, or -errno on failure.
|
|
*/
|
|
int (*keyslot_evict)(struct blk_crypto_profile *profile,
|
|
const struct blk_crypto_key *key,
|
|
unsigned int slot);
|
|
};
|
|
|
|
/**
|
|
* struct blk_crypto_profile - inline encryption profile for a device
|
|
*
|
|
* This struct contains a storage device's inline encryption capabilities (e.g.
|
|
* the supported crypto algorithms), driver-provided functions to control the
|
|
* inline encryption hardware (e.g. programming and evicting keys), and optional
|
|
* device-independent keyslot management data.
|
|
*/
|
|
struct blk_crypto_profile {
|
|
|
|
/* public: Drivers must initialize the following fields. */
|
|
|
|
/**
|
|
* @ll_ops: Driver-provided functions to control the inline encryption
|
|
* hardware, e.g. program and evict keys.
|
|
*/
|
|
struct blk_crypto_ll_ops ll_ops;
|
|
|
|
/**
|
|
* @max_dun_bytes_supported: The maximum number of bytes supported for
|
|
* specifying the data unit number (DUN). Specifically, the range of
|
|
* supported DUNs is 0 through (1 << (8 * max_dun_bytes_supported)) - 1.
|
|
*/
|
|
unsigned int max_dun_bytes_supported;
|
|
|
|
/**
|
|
* @modes_supported: Array of bitmasks that specifies whether each
|
|
* combination of crypto mode and data unit size is supported.
|
|
* Specifically, the i'th bit of modes_supported[crypto_mode] is set if
|
|
* crypto_mode can be used with a data unit size of (1 << i). Note that
|
|
* only data unit sizes that are powers of 2 can be supported.
|
|
*/
|
|
unsigned int modes_supported[BLK_ENCRYPTION_MODE_MAX];
|
|
|
|
/**
|
|
* @dev: An optional device for runtime power management. If the driver
|
|
* provides this device, it will be runtime-resumed before any function
|
|
* in @ll_ops is called and will remain resumed during the call.
|
|
*/
|
|
struct device *dev;
|
|
|
|
/* private: The following fields shouldn't be accessed by drivers. */
|
|
|
|
/* Number of keyslots, or 0 if not applicable */
|
|
unsigned int num_slots;
|
|
|
|
/*
|
|
* Serializes all calls to functions in @ll_ops as well as all changes
|
|
* to @slot_hashtable. This can also be taken in read mode to look up
|
|
* keyslots while ensuring that they can't be changed concurrently.
|
|
*/
|
|
struct rw_semaphore lock;
|
|
struct lock_class_key lockdep_key;
|
|
|
|
/* List of idle slots, with least recently used slot at front */
|
|
wait_queue_head_t idle_slots_wait_queue;
|
|
struct list_head idle_slots;
|
|
spinlock_t idle_slots_lock;
|
|
|
|
/*
|
|
* Hash table which maps struct *blk_crypto_key to keyslots, so that we
|
|
* can find a key's keyslot in O(1) time rather than O(num_slots).
|
|
* Protected by 'lock'.
|
|
*/
|
|
struct hlist_head *slot_hashtable;
|
|
unsigned int log_slot_ht_size;
|
|
|
|
/* Per-keyslot data */
|
|
struct blk_crypto_keyslot *slots;
|
|
};
|
|
|
|
int blk_crypto_profile_init(struct blk_crypto_profile *profile,
|
|
unsigned int num_slots);
|
|
|
|
int devm_blk_crypto_profile_init(struct device *dev,
|
|
struct blk_crypto_profile *profile,
|
|
unsigned int num_slots);
|
|
|
|
unsigned int blk_crypto_keyslot_index(struct blk_crypto_keyslot *slot);
|
|
|
|
void blk_crypto_reprogram_all_keys(struct blk_crypto_profile *profile);
|
|
|
|
void blk_crypto_profile_destroy(struct blk_crypto_profile *profile);
|
|
|
|
void blk_crypto_intersect_capabilities(struct blk_crypto_profile *parent,
|
|
const struct blk_crypto_profile *child);
|
|
|
|
bool blk_crypto_has_capabilities(const struct blk_crypto_profile *target,
|
|
const struct blk_crypto_profile *reference);
|
|
|
|
void blk_crypto_update_capabilities(struct blk_crypto_profile *dst,
|
|
const struct blk_crypto_profile *src);
|
|
|
|
#endif /* __LINUX_BLK_CRYPTO_PROFILE_H */
|