crypto: vmac - use crypto_grab_cipher() and simplify error paths

Make the vmac64 template use the new function crypto_grab_cipher() to
initialize its cipher spawn.

This is needed to make all spawns be initialized in a consistent way.

This required making vmac_create() allocate the instance directly rather
than use shash_alloc_instance().

Also simplify the error handling by taking advantage of crypto_drop_*()
now accepting (as a no-op) spawns that haven't been initialized yet, and
by taking advantage of crypto_grab_*() now handling ERR_PTR() names.

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 19:59:03 -08:00 committed by Herbert Xu
parent 1d0459cd83
commit 3b4e73d8ca

View File

@ -618,6 +618,7 @@ static void vmac_exit_tfm(struct crypto_tfm *tfm)
static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
{
struct shash_instance *inst;
struct crypto_cipher_spawn *spawn;
struct crypto_alg *alg;
int err;
@ -625,25 +626,24 @@ static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
if (err)
return err;
alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
return PTR_ERR(alg);
inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
if (!inst)
return -ENOMEM;
spawn = shash_instance_ctx(inst);
err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),
crypto_attr_alg_name(tb[1]), 0, 0);
if (err)
goto err_free_inst;
alg = crypto_spawn_cipher_alg(spawn);
err = -EINVAL;
if (alg->cra_blocksize != VMAC_NONCEBYTES)
goto out_put_alg;
goto err_free_inst;
inst = shash_alloc_instance(tmpl->name, alg);
err = PTR_ERR(inst);
if (IS_ERR(inst))
goto out_put_alg;
err = crypto_init_spawn(shash_instance_ctx(inst), alg,
shash_crypto_instance(inst),
CRYPTO_ALG_TYPE_MASK);
err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);
if (err)
goto out_free_inst;
goto err_free_inst;
inst->alg.base.cra_priority = alg->cra_priority;
inst->alg.base.cra_blocksize = alg->cra_blocksize;
@ -662,12 +662,9 @@ static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
err = shash_register_instance(tmpl, inst);
if (err) {
out_free_inst:
err_free_inst:
shash_free_instance(shash_crypto_instance(inst));
}
out_put_alg:
crypto_mod_put(alg);
return err;
}