^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright 2019 Google LLC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * DOC: The Keyslot Manager
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * Many devices with inline encryption support have a limited number of "slots"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * into which encryption contexts may be programmed, and requests can be tagged
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * with a slot number to specify the key to use for en/decryption.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * As the number of slots is limited, and programming keys is expensive on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * many inline encryption hardware, we don't want to program the same key into
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * multiple slots - if multiple requests are using the same key, we want to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * program just one slot with that key and use that slot for all requests.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * The keyslot manager manages these keyslots appropriately, and also acts as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * an abstraction between the inline encryption hardware and the upper layers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * Lower layer devices will set up a keyslot manager in their request queue
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * and tell it how to perform device specific operations like programming/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * evicting keys from keyslots.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * Upper layers will call blk_ksm_get_slot_for_key() to program a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * key into some slot in the inline encryption hardware.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #define pr_fmt(fmt) "blk-crypto: " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/keyslot-manager.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <linux/atomic.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #include <linux/pm_runtime.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #include <linux/wait.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #include <linux/blkdev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) struct blk_ksm_keyslot {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) atomic_t slot_refs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct list_head idle_slot_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) struct hlist_node hash_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) const struct blk_crypto_key *key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) struct blk_keyslot_manager *ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) static inline void blk_ksm_hw_enter(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) * Calling into the driver requires ksm->lock held and the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * resumed. But we must resume the device first, since that can acquire
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * and release ksm->lock via blk_ksm_reprogram_all_keys().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) if (ksm->dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) pm_runtime_get_sync(ksm->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) down_write(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) static inline void blk_ksm_hw_exit(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) up_write(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) if (ksm->dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) pm_runtime_put_sync(ksm->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static inline bool blk_ksm_is_passthrough(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) return ksm->num_slots == 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) * blk_ksm_init() - Initialize a keyslot manager
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) * @ksm: The keyslot_manager to initialize.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) * @num_slots: The number of key slots to manage.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) * Allocate memory for keyslots and initialize a keyslot manager. Called by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) * e.g. storage drivers to set up a keyslot manager in their request_queue.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) * Return: 0 on success, or else a negative error code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) unsigned int slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) unsigned int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) unsigned int slot_hashtable_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) memset(ksm, 0, sizeof(*ksm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) if (num_slots == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) ksm->slots = kvcalloc(num_slots, sizeof(ksm->slots[0]), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (!ksm->slots)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) ksm->num_slots = num_slots;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) init_rwsem(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) init_waitqueue_head(&ksm->idle_slots_wait_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) INIT_LIST_HEAD(&ksm->idle_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) for (slot = 0; slot < num_slots; slot++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) ksm->slots[slot].ksm = ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) list_add_tail(&ksm->slots[slot].idle_slot_node,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) &ksm->idle_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) spin_lock_init(&ksm->idle_slots_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) slot_hashtable_size = roundup_pow_of_two(num_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) * hash_ptr() assumes bits != 0, so ensure the hash table has at least 2
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) * buckets. This only makes a difference when there is only 1 keyslot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) if (slot_hashtable_size < 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) slot_hashtable_size = 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) ksm->log_slot_ht_size = ilog2(slot_hashtable_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) ksm->slot_hashtable = kvmalloc_array(slot_hashtable_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) sizeof(ksm->slot_hashtable[0]),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) if (!ksm->slot_hashtable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) goto err_destroy_ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) for (i = 0; i < slot_hashtable_size; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) INIT_HLIST_HEAD(&ksm->slot_hashtable[i]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) err_destroy_ksm:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) blk_ksm_destroy(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) EXPORT_SYMBOL_GPL(blk_ksm_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) static void blk_ksm_destroy_callback(void *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) blk_ksm_destroy(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * devm_blk_ksm_init() - Resource-managed blk_ksm_init()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) * @dev: The device which owns the blk_keyslot_manager.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) * @ksm: The blk_keyslot_manager to initialize.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) * @num_slots: The number of key slots to manage.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) * Like blk_ksm_init(), but causes blk_ksm_destroy() to be called automatically
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) * on driver detach.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) * Return: 0 on success, or else a negative error code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) int devm_blk_ksm_init(struct device *dev, struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) unsigned int num_slots)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) int err = blk_ksm_init(ksm, num_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) return devm_add_action_or_reset(dev, blk_ksm_destroy_callback, ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) EXPORT_SYMBOL_GPL(devm_blk_ksm_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) static inline struct hlist_head *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) blk_ksm_hash_bucket_for_key(struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) const struct blk_crypto_key *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) return &ksm->slot_hashtable[hash_ptr(key, ksm->log_slot_ht_size)];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) static void blk_ksm_remove_slot_from_lru_list(struct blk_ksm_keyslot *slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) struct blk_keyslot_manager *ksm = slot->ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) spin_lock_irqsave(&ksm->idle_slots_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) list_del(&slot->idle_slot_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) spin_unlock_irqrestore(&ksm->idle_slots_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) static struct blk_ksm_keyslot *blk_ksm_find_keyslot(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) const struct blk_crypto_key *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) const struct hlist_head *head = blk_ksm_hash_bucket_for_key(ksm, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) struct blk_ksm_keyslot *slotp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) hlist_for_each_entry(slotp, head, hash_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) if (slotp->key == key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) return slotp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) static struct blk_ksm_keyslot *blk_ksm_find_and_grab_keyslot(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) const struct blk_crypto_key *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) struct blk_ksm_keyslot *slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) slot = blk_ksm_find_keyslot(ksm, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) if (!slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) if (atomic_inc_return(&slot->slot_refs) == 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) /* Took first reference to this slot; remove it from LRU list */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) blk_ksm_remove_slot_from_lru_list(slot);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) return slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) return slot - slot->ksm->slots;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) EXPORT_SYMBOL_GPL(blk_ksm_get_slot_idx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) * blk_ksm_get_slot_for_key() - Program a key into a keyslot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) * @ksm: The keyslot manager to program the key into.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) * @key: Pointer to the key object to program, including the raw key, crypto
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) * mode, and data unit size.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) * @slot_ptr: A pointer to return the pointer of the allocated keyslot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) * Get a keyslot that's been programmed with the specified key. If one already
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) * exists, return it with incremented refcount. Otherwise, wait for a keyslot
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) * to become idle and program it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) * Context: Process context. Takes and releases ksm->lock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) * Return: BLK_STS_OK on success (and keyslot is set to the pointer of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) * allocated keyslot), or some other blk_status_t otherwise (and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) * keyslot is set to NULL).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) const struct blk_crypto_key *key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) struct blk_ksm_keyslot **slot_ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) struct blk_ksm_keyslot *slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) int slot_idx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) *slot_ptr = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) if (blk_ksm_is_passthrough(ksm))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) return BLK_STS_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) down_read(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) slot = blk_ksm_find_and_grab_keyslot(ksm, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) up_read(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) if (slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) goto success;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) for (;;) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) blk_ksm_hw_enter(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) slot = blk_ksm_find_and_grab_keyslot(ksm, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) if (slot) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) goto success;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) * If we're here, that means there wasn't a slot that was
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) * already programmed with the key. So try to program it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) if (!list_empty(&ksm->idle_slots))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) wait_event(ksm->idle_slots_wait_queue,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) !list_empty(&ksm->idle_slots));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) slot = list_first_entry(&ksm->idle_slots, struct blk_ksm_keyslot,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) idle_slot_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) slot_idx = blk_ksm_get_slot_idx(slot);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot_idx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) wake_up(&ksm->idle_slots_wait_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) return errno_to_blk_status(err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) /* Move this slot to the hash list for the new key. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) if (slot->key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) hlist_del(&slot->hash_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) slot->key = key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) hlist_add_head(&slot->hash_node, blk_ksm_hash_bucket_for_key(ksm, key));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) atomic_set(&slot->slot_refs, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) blk_ksm_remove_slot_from_lru_list(slot);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) success:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) *slot_ptr = slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) return BLK_STS_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) * blk_ksm_put_slot() - Release a reference to a slot
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) * @slot: The keyslot to release the reference of.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) * Context: Any context.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) void blk_ksm_put_slot(struct blk_ksm_keyslot *slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) struct blk_keyslot_manager *ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) if (!slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) ksm = slot->ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) if (atomic_dec_and_lock_irqsave(&slot->slot_refs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) &ksm->idle_slots_lock, flags)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) list_add_tail(&slot->idle_slot_node, &ksm->idle_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) spin_unlock_irqrestore(&ksm->idle_slots_lock, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) wake_up(&ksm->idle_slots_wait_queue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) * blk_ksm_crypto_cfg_supported() - Find out if a crypto configuration is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) * supported by a ksm.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) * @ksm: The keyslot manager to check
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) * @cfg: The crypto configuration to check for.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) * Checks for crypto_mode/data unit size/dun bytes support.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) * Return: Whether or not this ksm supports the specified crypto config.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) const struct blk_crypto_config *cfg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) if (!ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) if (!(ksm->crypto_modes_supported[cfg->crypto_mode] &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) cfg->data_unit_size))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) if (ksm->max_dun_bytes_supported < cfg->dun_bytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) if (cfg->is_hw_wrapped) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) if (!(ksm->features & BLK_CRYPTO_FEATURE_WRAPPED_KEYS))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) if (!(ksm->features & BLK_CRYPTO_FEATURE_STANDARD_KEYS))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) * blk_ksm_evict_key() - Evict a key from the lower layer device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) * @ksm: The keyslot manager to evict from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) * @key: The key to evict
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) * Find the keyslot that the specified key was programmed into, and evict that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) * slot from the lower layer device. The slot must not be in use by any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) * in-flight IO when this function is called.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) * Context: Process context. Takes and releases ksm->lock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) * Return: 0 on success or if there's no keyslot with the specified key, -EBUSY
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) * if the keyslot is still in use, or another -errno value on other
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) * error.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) const struct blk_crypto_key *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) struct blk_ksm_keyslot *slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) int err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) if (blk_ksm_is_passthrough(ksm)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) if (ksm->ksm_ll_ops.keyslot_evict) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) blk_ksm_hw_enter(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) err = ksm->ksm_ll_ops.keyslot_evict(ksm, key, -1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) blk_ksm_hw_enter(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) slot = blk_ksm_find_keyslot(ksm, key);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) if (!slot)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) if (WARN_ON_ONCE(atomic_read(&slot->slot_refs) != 0)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) err = -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) err = ksm->ksm_ll_ops.keyslot_evict(ksm, key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) blk_ksm_get_slot_idx(slot));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) hlist_del(&slot->hash_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) slot->key = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) * blk_ksm_reprogram_all_keys() - Re-program all keyslots.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) * @ksm: The keyslot manager
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) * Re-program all keyslots that are supposed to have a key programmed. This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) * intended only for use by drivers for hardware that loses its keys on reset.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) * Context: Process context. Takes and releases ksm->lock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) unsigned int slot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) if (blk_ksm_is_passthrough(ksm))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) /* This is for device initialization, so don't resume the device */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) down_write(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) for (slot = 0; slot < ksm->num_slots; slot++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) const struct blk_crypto_key *key = ksm->slots[slot].key;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) if (!key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) WARN_ON(err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) up_write(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) EXPORT_SYMBOL_GPL(blk_ksm_reprogram_all_keys);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) void blk_ksm_destroy(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) if (!ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) kvfree(ksm->slot_hashtable);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) kvfree_sensitive(ksm->slots, sizeof(ksm->slots[0]) * ksm->num_slots);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) memzero_explicit(ksm, sizeof(*ksm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) EXPORT_SYMBOL_GPL(blk_ksm_destroy);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) if (blk_integrity_queue_supports_integrity(q)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) pr_warn("Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) q->ksm = ksm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) EXPORT_SYMBOL_GPL(blk_ksm_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) void blk_ksm_unregister(struct request_queue *q)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) q->ksm = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) * blk_ksm_derive_raw_secret() - Derive software secret from wrapped key
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) * @ksm: The keyslot manager
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) * @wrapped_key: The wrapped key
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) * @wrapped_key_size: Size of the wrapped key in bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) * @secret: (output) the software secret
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) * @secret_size: (output) the number of secret bytes to derive
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) * Given a hardware-wrapped key, ask the hardware to derive a secret which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) * software can use for cryptographic tasks other than inline encryption. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) * derived secret is guaranteed to be cryptographically isolated from the key
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) * with which any inline encryption with this wrapped key would actually be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) * done. I.e., both will be derived from the unwrapped key.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) * Return: 0 on success, -EOPNOTSUPP if hardware-wrapped keys are unsupported,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) * or another -errno code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) int blk_ksm_derive_raw_secret(struct blk_keyslot_manager *ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) const u8 *wrapped_key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) unsigned int wrapped_key_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) u8 *secret, unsigned int secret_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) if (ksm->ksm_ll_ops.derive_raw_secret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) blk_ksm_hw_enter(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) err = ksm->ksm_ll_ops.derive_raw_secret(ksm, wrapped_key,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) wrapped_key_size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) secret, secret_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) blk_ksm_hw_exit(ksm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) err = -EOPNOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) EXPORT_SYMBOL_GPL(blk_ksm_derive_raw_secret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) * blk_ksm_intersect_modes() - restrict supported modes by child device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) * @parent: The keyslot manager for parent device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) * @child: The keyslot manager for child device, or NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) * Clear any crypto mode support bits in @parent that aren't set in @child.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) * If @child is NULL, then all parent bits are cleared.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) * Only use this when setting up the keyslot manager for a layered device,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) * before it's been exposed yet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) const struct blk_keyslot_manager *child)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) if (child) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) unsigned int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) parent->max_dun_bytes_supported =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) min(parent->max_dun_bytes_supported,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) child->max_dun_bytes_supported);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) for (i = 0; i < ARRAY_SIZE(child->crypto_modes_supported);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) parent->crypto_modes_supported[i] &=
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) child->crypto_modes_supported[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) parent->features &= child->features;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) parent->max_dun_bytes_supported = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) memset(parent->crypto_modes_supported, 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) sizeof(parent->crypto_modes_supported));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) parent->features = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) EXPORT_SYMBOL_GPL(blk_ksm_intersect_modes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) * blk_ksm_is_superset() - Check if a KSM supports a superset of crypto modes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) * and DUN bytes that another KSM supports. Here,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) * "superset" refers to the mathematical meaning of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) * word - i.e. if two KSMs have the *same* capabilities,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) * they *are* considered supersets of each other.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) * @ksm_superset: The KSM that we want to verify is a superset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) * @ksm_subset: The KSM that we want to verify is a subset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) * Return: True if @ksm_superset supports a superset of the crypto modes and DUN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) * bytes that @ksm_subset supports.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) bool blk_ksm_is_superset(struct blk_keyslot_manager *ksm_superset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) struct blk_keyslot_manager *ksm_subset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) if (!ksm_subset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) if (!ksm_superset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) for (i = 0; i < ARRAY_SIZE(ksm_superset->crypto_modes_supported); i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) if (ksm_subset->crypto_modes_supported[i] &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) (~ksm_superset->crypto_modes_supported[i])) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) if (ksm_subset->max_dun_bytes_supported >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) ksm_superset->max_dun_bytes_supported) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) if (ksm_subset->features & ~ksm_superset->features)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) EXPORT_SYMBOL_GPL(blk_ksm_is_superset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) * blk_ksm_update_capabilities() - Update the restrictions of a KSM to those of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) * another KSM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) * @target_ksm: The KSM whose restrictions to update.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) * @reference_ksm: The KSM to whose restrictions this function will update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) * @target_ksm's restrictions to.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) * Blk-crypto requires that crypto capabilities that were
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) * advertised when a bio was created continue to be supported by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) * device until that bio is ended. This is turn means that a device cannot
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) * shrink its advertised crypto capabilities without any explicit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) * synchronization with upper layers. So if there's no such explicit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) * synchronization, @reference_ksm must support all the crypto capabilities that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) * @target_ksm does
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) * (i.e. we need blk_ksm_is_superset(@reference_ksm, @target_ksm) == true).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) * Note also that as long as the crypto capabilities are being expanded, the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) * order of updates becoming visible is not important because it's alright
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) * for blk-crypto to see stale values - they only cause blk-crypto to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) * believe that a crypto capability isn't supported when it actually is (which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) * might result in blk-crypto-fallback being used if available, or the bio being
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) * failed).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) void blk_ksm_update_capabilities(struct blk_keyslot_manager *target_ksm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) struct blk_keyslot_manager *reference_ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) memcpy(target_ksm->crypto_modes_supported,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) reference_ksm->crypto_modes_supported,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) sizeof(target_ksm->crypto_modes_supported));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) target_ksm->max_dun_bytes_supported =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) reference_ksm->max_dun_bytes_supported;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) target_ksm->features = reference_ksm->features;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) EXPORT_SYMBOL_GPL(blk_ksm_update_capabilities);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) * blk_ksm_init_passthrough() - Init a passthrough keyslot manager
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) * @ksm: The keyslot manager to init
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) * Initialize a passthrough keyslot manager.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) * Called by e.g. storage drivers to set up a keyslot manager in their
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) * request_queue, when the storage driver wants to manage its keys by itself.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) * This is useful for inline encryption hardware that doesn't have the concept
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) * of keyslots, and for layered devices.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) void blk_ksm_init_passthrough(struct blk_keyslot_manager *ksm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) memset(ksm, 0, sizeof(*ksm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) init_rwsem(&ksm->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) EXPORT_SYMBOL_GPL(blk_ksm_init_passthrough);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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