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