crypto: cipher - introduce crypto_cipher_spawn and crypto_grab_cipher()

Currently, "cipher" (single-block cipher) spawns are usually initialized
by using crypto_get_attr_alg() to look up the algorithm, then calling
crypto_init_spawn().  In one case, crypto_grab_spawn() is used directly.

The former way is different from how skcipher, aead, and akcipher spawns
are initialized (they use crypto_grab_*()), and for no good reason.
This difference introduces unnecessary complexity.

The crypto_grab_*() functions used to have some problems, like not
holding a reference to the algorithm and requiring the caller to
initialize spawn->base.inst.  But those problems are fixed now.

Also, the cipher spawns are not strongly typed; e.g., the API requires
that the user manually specify the flags CRYPTO_ALG_TYPE_CIPHER and
CRYPTO_ALG_TYPE_MASK.  Though the "cipher" algorithm type itself isn't
yet strongly typed, we can start by making the spawns strongly typed.

So, let's introduce a new 'struct crypto_cipher_spawn', and functions
crypto_grab_cipher() and crypto_drop_cipher() to grab and drop them.

Later patches will convert all cipher spawns to use these, then make
crypto_spawn_cipher() take 'struct crypto_cipher_spawn' as well, instead
of a bare 'struct crypto_spawn' as it currently does.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers 2020-01-02 19:58:51 -08:00 committed by Herbert Xu
parent 84a9c938e5
commit 0764ac2876

View File

@ -208,6 +208,31 @@ static inline void *crypto_instance_ctx(struct crypto_instance *inst)
return inst->__ctx;
}
struct crypto_cipher_spawn {
struct crypto_spawn base;
};
static inline int crypto_grab_cipher(struct crypto_cipher_spawn *spawn,
struct crypto_instance *inst,
const char *name, u32 type, u32 mask)
{
type &= ~CRYPTO_ALG_TYPE_MASK;
type |= CRYPTO_ALG_TYPE_CIPHER;
mask |= CRYPTO_ALG_TYPE_MASK;
return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
}
static inline void crypto_drop_cipher(struct crypto_cipher_spawn *spawn)
{
crypto_drop_spawn(&spawn->base);
}
static inline struct crypto_alg *crypto_spawn_cipher_alg(
struct crypto_cipher_spawn *spawn)
{
return spawn->base.alg;
}
static inline struct crypto_cipher *crypto_spawn_cipher(
struct crypto_spawn *spawn)
{