1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright 2019 Google LLC
  4 */
  5
  6#ifndef __LINUX_BLK_CRYPTO_INTERNAL_H
  7#define __LINUX_BLK_CRYPTO_INTERNAL_H
  8
  9#include <linux/bio.h>
 10#include <linux/blk-mq.h>
 11
 12/* Represents a crypto mode supported by blk-crypto  */
 13struct blk_crypto_mode {
 14	const char *name; /* name of this mode, shown in sysfs */
 15	const char *cipher_str; /* crypto API name (for fallback case) */
 16	unsigned int keysize; /* key size in bytes */
 17	unsigned int ivsize; /* iv size in bytes */
 18};
 19
 20extern const struct blk_crypto_mode blk_crypto_modes[];
 21
 22#ifdef CONFIG_BLK_INLINE_ENCRYPTION
 23
 24int blk_crypto_sysfs_register(struct gendisk *disk);
 25
 26void blk_crypto_sysfs_unregister(struct gendisk *disk);
 27
 28void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
 29			     unsigned int inc);
 30
 31bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio);
 32
 33bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
 34			     struct bio_crypt_ctx *bc2);
 35
 36static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
 37						struct bio *bio)
 38{
 39	return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
 40				       bio->bi_crypt_context);
 41}
 42
 43static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
 44						 struct bio *bio)
 45{
 46	return bio_crypt_ctx_mergeable(bio->bi_crypt_context,
 47				       bio->bi_iter.bi_size, req->crypt_ctx);
 48}
 49
 50static inline bool bio_crypt_ctx_merge_rq(struct request *req,
 51					  struct request *next)
 52{
 53	return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
 54				       next->crypt_ctx);
 55}
 56
 57static inline void blk_crypto_rq_set_defaults(struct request *rq)
 58{
 59	rq->crypt_ctx = NULL;
 60	rq->crypt_keyslot = NULL;
 61}
 62
 63static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
 64{
 65	return rq->crypt_ctx;
 66}
 67
 68blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
 69				    const struct blk_crypto_key *key,
 70				    struct blk_crypto_keyslot **slot_ptr);
 71
 72void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot);
 73
 74int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
 75			   const struct blk_crypto_key *key);
 76
 77bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
 78				const struct blk_crypto_config *cfg);
 79
 80#else /* CONFIG_BLK_INLINE_ENCRYPTION */
 81
 82static inline int blk_crypto_sysfs_register(struct gendisk *disk)
 83{
 84	return 0;
 85}
 86
 87static inline void blk_crypto_sysfs_unregister(struct gendisk *disk)
 88{
 89}
 90
 91static inline bool bio_crypt_rq_ctx_compatible(struct request *rq,
 92					       struct bio *bio)
 93{
 94	return true;
 95}
 96
 97static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
 98						 struct bio *bio)
 99{
100	return true;
101}
102
103static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
104						struct bio *bio)
105{
106	return true;
107}
108
109static inline bool bio_crypt_ctx_merge_rq(struct request *req,
110					  struct request *next)
111{
112	return true;
113}
114
115static inline void blk_crypto_rq_set_defaults(struct request *rq) { }
116
117static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
118{
119	return false;
120}
121
122#endif /* CONFIG_BLK_INLINE_ENCRYPTION */
123
124void __bio_crypt_advance(struct bio *bio, unsigned int bytes);
125static inline void bio_crypt_advance(struct bio *bio, unsigned int bytes)
126{
127	if (bio_has_crypt_ctx(bio))
128		__bio_crypt_advance(bio, bytes);
129}
130
131void __bio_crypt_free_ctx(struct bio *bio);
132static inline void bio_crypt_free_ctx(struct bio *bio)
133{
134	if (bio_has_crypt_ctx(bio))
135		__bio_crypt_free_ctx(bio);
136}
137
138static inline void bio_crypt_do_front_merge(struct request *rq,
139					    struct bio *bio)
140{
141#ifdef CONFIG_BLK_INLINE_ENCRYPTION
142	if (bio_has_crypt_ctx(bio))
143		memcpy(rq->crypt_ctx->bc_dun, bio->bi_crypt_context->bc_dun,
144		       sizeof(rq->crypt_ctx->bc_dun));
145#endif
146}
147
148bool __blk_crypto_bio_prep(struct bio **bio_ptr);
149static inline bool blk_crypto_bio_prep(struct bio **bio_ptr)
150{
151	if (bio_has_crypt_ctx(*bio_ptr))
152		return __blk_crypto_bio_prep(bio_ptr);
153	return true;
154}
155
156blk_status_t __blk_crypto_init_request(struct request *rq);
157static inline blk_status_t blk_crypto_init_request(struct request *rq)
158{
159	if (blk_crypto_rq_is_encrypted(rq))
160		return __blk_crypto_init_request(rq);
161	return BLK_STS_OK;
162}
163
164void __blk_crypto_free_request(struct request *rq);
165static inline void blk_crypto_free_request(struct request *rq)
166{
167	if (blk_crypto_rq_is_encrypted(rq))
168		__blk_crypto_free_request(rq);
169}
170
171int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
172			     gfp_t gfp_mask);
173/**
174 * blk_crypto_rq_bio_prep - Prepare a request's crypt_ctx when its first bio
175 *			    is inserted
176 * @rq: The request to prepare
177 * @bio: The first bio being inserted into the request
178 * @gfp_mask: Memory allocation flags
179 *
180 * Return: 0 on success, -ENOMEM if out of memory.  -ENOMEM is only possible if
181 *	   @gfp_mask doesn't include %__GFP_DIRECT_RECLAIM.
182 */
183static inline int blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
184					 gfp_t gfp_mask)
185{
186	if (bio_has_crypt_ctx(bio))
187		return __blk_crypto_rq_bio_prep(rq, bio, gfp_mask);
188	return 0;
189}
190
191/**
192 * blk_crypto_insert_cloned_request - Prepare a cloned request to be inserted
193 *				      into a request queue.
194 * @rq: the request being queued
195 *
196 * Return: BLK_STS_OK on success, nonzero on error.
197 */
198static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq)
199{
200
201	if (blk_crypto_rq_is_encrypted(rq))
202		return blk_crypto_init_request(rq);
203	return BLK_STS_OK;
204}
205
206#ifdef CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK
207
208int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num);
209
210bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr);
211
212int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key);
213
214#else /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
215
216static inline int
217blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
218{
219	pr_warn_once("crypto API fallback is disabled\n");
220	return -ENOPKG;
221}
222
223static inline bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
224{
225	pr_warn_once("crypto API fallback disabled; failing request.\n");
226	(*bio_ptr)->bi_status = BLK_STS_NOTSUPP;
227	return false;
228}
229
230static inline int
231blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
232{
233	return 0;
234}
235
236#endif /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
237
238#endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */