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 */
13 struct 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
20 extern const struct blk_crypto_mode blk_crypto_modes[];
21
22 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
23
24 int blk_crypto_sysfs_register(struct gendisk *disk);
25
26 void blk_crypto_sysfs_unregister(struct gendisk *disk);
27
28 void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
29 unsigned int inc);
30
31 bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio);
32
33 bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
34 struct bio_crypt_ctx *bc2);
35
36 static 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
43 static 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
50 static 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
57 static inline void blk_crypto_rq_set_defaults(struct request *rq)
58 {
59 rq->crypt_ctx = NULL;
60 rq->crypt_keyslot = NULL;
61 }
62
63 static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
64 {
65 return rq->crypt_ctx;
66 }
67
68 static inline bool blk_crypto_rq_has_keyslot(struct request *rq)
69 {
70 return rq->crypt_keyslot;
71 }
72
73 blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
74 const struct blk_crypto_key *key,
75 struct blk_crypto_keyslot **slot_ptr);
76
77 void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot);
78
79 int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
80 const struct blk_crypto_key *key);
81
82 bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
83 const struct blk_crypto_config *cfg);
84
85 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
86
87 static inline int blk_crypto_sysfs_register(struct gendisk *disk)
88 {
89 return 0;
90 }
91
92 static inline void blk_crypto_sysfs_unregister(struct gendisk *disk)
93 {
94 }
95
96 static inline bool bio_crypt_rq_ctx_compatible(struct request *rq,
97 struct bio *bio)
98 {
99 return true;
100 }
101
102 static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
103 struct bio *bio)
104 {
105 return true;
106 }
107
108 static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
109 struct bio *bio)
110 {
111 return true;
112 }
113
114 static inline bool bio_crypt_ctx_merge_rq(struct request *req,
115 struct request *next)
116 {
117 return true;
118 }
119
120 static inline void blk_crypto_rq_set_defaults(struct request *rq) { }
121
122 static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
123 {
124 return false;
125 }
126
127 static inline bool blk_crypto_rq_has_keyslot(struct request *rq)
128 {
129 return false;
130 }
131
132 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
133
134 void __bio_crypt_advance(struct bio *bio, unsigned int bytes);
135 static inline void bio_crypt_advance(struct bio *bio, unsigned int bytes)
136 {
137 if (bio_has_crypt_ctx(bio))
138 __bio_crypt_advance(bio, bytes);
139 }
140
141 void __bio_crypt_free_ctx(struct bio *bio);
142 static inline void bio_crypt_free_ctx(struct bio *bio)
143 {
144 if (bio_has_crypt_ctx(bio))
145 __bio_crypt_free_ctx(bio);
146 }
147
148 static inline void bio_crypt_do_front_merge(struct request *rq,
149 struct bio *bio)
150 {
151 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
152 if (bio_has_crypt_ctx(bio))
153 memcpy(rq->crypt_ctx->bc_dun, bio->bi_crypt_context->bc_dun,
154 sizeof(rq->crypt_ctx->bc_dun));
155 #endif
156 }
157
158 bool __blk_crypto_bio_prep(struct bio **bio_ptr);
159 static inline bool blk_crypto_bio_prep(struct bio **bio_ptr)
160 {
161 if (bio_has_crypt_ctx(*bio_ptr))
162 return __blk_crypto_bio_prep(bio_ptr);
163 return true;
164 }
165
166 blk_status_t __blk_crypto_rq_get_keyslot(struct request *rq);
167 static inline blk_status_t blk_crypto_rq_get_keyslot(struct request *rq)
168 {
169 if (blk_crypto_rq_is_encrypted(rq))
170 return __blk_crypto_rq_get_keyslot(rq);
171 return BLK_STS_OK;
172 }
173
174 void __blk_crypto_rq_put_keyslot(struct request *rq);
175 static inline void blk_crypto_rq_put_keyslot(struct request *rq)
176 {
177 if (blk_crypto_rq_has_keyslot(rq))
178 __blk_crypto_rq_put_keyslot(rq);
179 }
180
181 void __blk_crypto_free_request(struct request *rq);
182 static inline void blk_crypto_free_request(struct request *rq)
183 {
184 if (blk_crypto_rq_is_encrypted(rq))
185 __blk_crypto_free_request(rq);
186 }
187
188 int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
189 gfp_t gfp_mask);
190 /**
191 * blk_crypto_rq_bio_prep - Prepare a request's crypt_ctx when its first bio
192 * is inserted
193 * @rq: The request to prepare
194 * @bio: The first bio being inserted into the request
195 * @gfp_mask: Memory allocation flags
196 *
197 * Return: 0 on success, -ENOMEM if out of memory. -ENOMEM is only possible if
198 * @gfp_mask doesn't include %__GFP_DIRECT_RECLAIM.
199 */
200 static inline int blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
201 gfp_t gfp_mask)
202 {
203 if (bio_has_crypt_ctx(bio))
204 return __blk_crypto_rq_bio_prep(rq, bio, gfp_mask);
205 return 0;
206 }
207
208 #ifdef CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK
209
210 int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num);
211
212 bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr);
213
214 int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key);
215
216 #else /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
217
218 static inline int
219 blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
220 {
221 pr_warn_once("crypto API fallback is disabled\n");
222 return -ENOPKG;
223 }
224
225 static inline bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
226 {
227 pr_warn_once("crypto API fallback disabled; failing request.\n");
228 (*bio_ptr)->bi_status = BLK_STS_NOTSUPP;
229 return false;
230 }
231
232 static inline int
233 blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
234 {
235 return 0;
236 }
237
238 #endif /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
239
240 #endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */
241
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