block/blk-crypto-internal.h

   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 */