1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright 2019 Google LLC
*/
#ifndef __LINUX_KEYSLOT_MANAGER_H
#define __LINUX_KEYSLOT_MANAGER_H
#include <linux/bio.h>
#include <linux/blk-crypto.h>
struct blk_keyslot_manager;
/**
* struct blk_ksm_ll_ops - functions to manage keyslots in hardware
* @keyslot_program: Program the specified key into the specified slot in the
* inline encryption hardware.
* @keyslot_evict: Evict key from the specified keyslot in the hardware.
* The key is provided so that e.g. dm layers can evict
* keys from the devices that they map over.
* Returns 0 on success, -errno otherwise.
*
* This structure should be provided by storage device drivers when they set up
* a keyslot manager - this structure holds the function ptrs that the keyslot
* manager will use to manipulate keyslots in the hardware.
*/
struct blk_ksm_ll_ops {
int (*keyslot_program)(struct blk_keyslot_manager *ksm,
const struct blk_crypto_key *key,
unsigned int slot);
int (*keyslot_evict)(struct blk_keyslot_manager *ksm,
const struct blk_crypto_key *key,
unsigned int slot);
};
struct blk_keyslot_manager {
/*
* The struct blk_ksm_ll_ops that this keyslot manager will use
* to perform operations like programming and evicting keys on the
* device
*/
struct blk_ksm_ll_ops ksm_ll_ops;
/*
* The maximum number of bytes supported for specifying the data unit
* number.
*/
unsigned int max_dun_bytes_supported;
/*
* Array of size BLK_ENCRYPTION_MODE_MAX of bitmasks that represents
* whether a crypto mode and data unit size are supported. The i'th
* bit of crypto_mode_supported[crypto_mode] is set iff a data unit
* size of (1 << i) is supported. We only support data unit sizes
* that are powers of 2.
*/
unsigned int crypto_modes_supported[BLK_ENCRYPTION_MODE_MAX];
/* Device for runtime power management (NULL if none) */
struct device *dev;
/* Here onwards are *private* fields for internal keyslot manager use */
unsigned int num_slots;
/* Protects programming and evicting keys from the device */
struct rw_semaphore lock;
/* 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_ksm_keyslot *slots;
};
int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots);
blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
const struct blk_crypto_key *key,
struct blk_ksm_keyslot **slot_ptr);
unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot);
void blk_ksm_put_slot(struct blk_ksm_keyslot *slot);
bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm,
const struct blk_crypto_config *cfg);
int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
const struct blk_crypto_key *key);
void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm);
void blk_ksm_destroy(struct blk_keyslot_manager *ksm);
void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent,
const struct blk_keyslot_manager *child);
void blk_ksm_init_passthrough(struct blk_keyslot_manager *ksm);
bool blk_ksm_is_superset(struct blk_keyslot_manager *ksm_superset,
struct blk_keyslot_manager *ksm_subset);
void blk_ksm_update_capabilities(struct blk_keyslot_manager *target_ksm,
struct blk_keyslot_manager *reference_ksm);
#endif /* __LINUX_KEYSLOT_MANAGER_H */
|