linux/block/blk-crypto-internal.h

202 lines
5.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright 2019 Google LLC
*/
#ifndef __LINUX_BLK_CRYPTO_INTERNAL_H
#define __LINUX_BLK_CRYPTO_INTERNAL_H
#include <linux/bio.h>
#include <linux/blkdev.h>
/* Represents a crypto mode supported by blk-crypto */
struct blk_crypto_mode {
const char *cipher_str; /* crypto API name (for fallback case) */
unsigned int keysize; /* key size in bytes */
unsigned int ivsize; /* iv size in bytes */
};
extern const struct blk_crypto_mode blk_crypto_modes[];
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
unsigned int inc);
bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio);
bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
struct bio_crypt_ctx *bc2);
static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
struct bio *bio)
{
return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
bio->bi_crypt_context);
}
static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
struct bio *bio)
{
return bio_crypt_ctx_mergeable(bio->bi_crypt_context,
bio->bi_iter.bi_size, req->crypt_ctx);
}
static inline bool bio_crypt_ctx_merge_rq(struct request *req,
struct request *next)
{
return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req),
next->crypt_ctx);
}
static inline void blk_crypto_rq_set_defaults(struct request *rq)
{
rq->crypt_ctx = NULL;
rq->crypt_keyslot = NULL;
}
static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
{
return rq->crypt_ctx;
}
#else /* CONFIG_BLK_INLINE_ENCRYPTION */
static inline bool bio_crypt_rq_ctx_compatible(struct request *rq,
struct bio *bio)
{
return true;
}
static inline bool bio_crypt_ctx_front_mergeable(struct request *req,
struct bio *bio)
{
return true;
}
static inline bool bio_crypt_ctx_back_mergeable(struct request *req,
struct bio *bio)
{
return true;
}
static inline bool bio_crypt_ctx_merge_rq(struct request *req,
struct request *next)
{
return true;
}
static inline void blk_crypto_rq_set_defaults(struct request *rq) { }
static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
{
return false;
}
#endif /* CONFIG_BLK_INLINE_ENCRYPTION */
void __bio_crypt_advance(struct bio *bio, unsigned int bytes);
static inline void bio_crypt_advance(struct bio *bio, unsigned int bytes)
{
if (bio_has_crypt_ctx(bio))
__bio_crypt_advance(bio, bytes);
}
void __bio_crypt_free_ctx(struct bio *bio);
static inline void bio_crypt_free_ctx(struct bio *bio)
{
if (bio_has_crypt_ctx(bio))
__bio_crypt_free_ctx(bio);
}
static inline void bio_crypt_do_front_merge(struct request *rq,
struct bio *bio)
{
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
if (bio_has_crypt_ctx(bio))
memcpy(rq->crypt_ctx->bc_dun, bio->bi_crypt_context->bc_dun,
sizeof(rq->crypt_ctx->bc_dun));
#endif
}
bool __blk_crypto_bio_prep(struct bio **bio_ptr);
static inline bool blk_crypto_bio_prep(struct bio **bio_ptr)
{
if (bio_has_crypt_ctx(*bio_ptr))
return __blk_crypto_bio_prep(bio_ptr);
return true;
}
blk_status_t __blk_crypto_init_request(struct request *rq);
static inline blk_status_t blk_crypto_init_request(struct request *rq)
{
if (blk_crypto_rq_is_encrypted(rq))
return __blk_crypto_init_request(rq);
return BLK_STS_OK;
}
void __blk_crypto_free_request(struct request *rq);
static inline void blk_crypto_free_request(struct request *rq)
{
if (blk_crypto_rq_is_encrypted(rq))
__blk_crypto_free_request(rq);
}
void __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
gfp_t gfp_mask);
static inline void blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
gfp_t gfp_mask)
{
if (bio_has_crypt_ctx(bio))
__blk_crypto_rq_bio_prep(rq, bio, gfp_mask);
}
/**
* blk_crypto_insert_cloned_request - Prepare a cloned request to be inserted
* into a request queue.
* @rq: the request being queued
*
* Return: BLK_STS_OK on success, nonzero on error.
*/
static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq)
{
if (blk_crypto_rq_is_encrypted(rq))
return blk_crypto_init_request(rq);
return BLK_STS_OK;
}
#ifdef CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK
int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num);
bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr);
int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key);
#else /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
static inline int
blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
{
pr_warn_once("crypto API fallback is disabled\n");
return -ENOPKG;
}
static inline bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
{
pr_warn_once("crypto API fallback disabled; failing request.\n");
(*bio_ptr)->bi_status = BLK_STS_NOTSUPP;
return false;
}
static inline int
blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
{
return 0;
}
#endif /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */
#endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */