crypto: algapi - use common mechanism for inheriting flags
The flag CRYPTO_ALG_ASYNC is "inherited" in the sense that when a
template is instantiated, the template will have CRYPTO_ALG_ASYNC set if
any of the algorithms it uses has CRYPTO_ALG_ASYNC set.
We'd like to add a second flag (CRYPTO_ALG_ALLOCATES_MEMORY) that gets
"inherited" in the same way. This is difficult because the handling of
CRYPTO_ALG_ASYNC is hardcoded everywhere. Address this by:
- Add CRYPTO_ALG_INHERITED_FLAGS, which contains the set of flags that
have these inheritance semantics.
- Add crypto_algt_inherited_mask(), for use by template ->create()
methods. It returns any of these flags that the user asked to be
unset and thus must be passed in the 'mask' to crypto_grab_*().
- Also modify crypto_check_attr_type() to handle computing the 'mask'
so that most templates can just use this.
- Make crypto_grab_*() propagate these flags to the template instance
being created so that templates don't have to do this themselves.
Make crypto/simd.c propagate these flags too, since it "wraps" another
algorithm, similar to a template.
Based on a patch by Mikulas Patocka <mpatocka@redhat.com>
(https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com).
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/ctr.c b/crypto/ctr.c
index 31ac4ae..ae8d88c 100644
--- a/crypto/ctr.c
+++ b/crypto/ctr.c
@@ -256,29 +256,22 @@ static void crypto_rfc3686_free(struct skcipher_instance *inst)
static int crypto_rfc3686_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
- struct crypto_attr_type *algt;
struct skcipher_instance *inst;
struct skcipher_alg *alg;
struct crypto_skcipher_spawn *spawn;
u32 mask;
-
int err;
- algt = crypto_get_attr_type(tb);
- if (IS_ERR(algt))
- return PTR_ERR(algt);
-
- if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
- return -EINVAL;
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
+ if (err)
+ return err;
+ mask |= crypto_requires_off(crypto_get_attr_type(tb),
+ CRYPTO_ALG_NEED_FALLBACK);
inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
if (!inst)
return -ENOMEM;
- mask = crypto_requires_sync(algt->type, algt->mask) |
- crypto_requires_off(algt->type, algt->mask,
- CRYPTO_ALG_NEED_FALLBACK);
-
spawn = skcipher_instance_ctx(inst);
err = crypto_grab_skcipher(spawn, skcipher_crypto_instance(inst),
@@ -310,8 +303,6 @@ static int crypto_rfc3686_create(struct crypto_template *tmpl,
inst->alg.base.cra_blocksize = 1;
inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
- inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
-
inst->alg.ivsize = CTR_RFC3686_IV_SIZE;
inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg);
inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) +