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/cryptd.c b/crypto/cryptd.c
index 2832122..a1bea0f 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -191,17 +191,20 @@ static inline struct cryptd_queue *cryptd_get_queue(struct crypto_tfm *tfm)
return ictx->queue;
}
-static inline void cryptd_check_internal(struct rtattr **tb, u32 *type,
- u32 *mask)
+static void cryptd_type_and_mask(struct crypto_attr_type *algt,
+ u32 *type, u32 *mask)
{
- struct crypto_attr_type *algt;
+ /*
+ * cryptd is allowed to wrap internal algorithms, but in that case the
+ * resulting cryptd instance will be marked as internal as well.
+ */
+ *type = algt->type & CRYPTO_ALG_INTERNAL;
+ *mask = algt->mask & CRYPTO_ALG_INTERNAL;
- algt = crypto_get_attr_type(tb);
- if (IS_ERR(algt))
- return;
+ /* No point in cryptd wrapping an algorithm that's already async. */
+ *mask |= CRYPTO_ALG_ASYNC;
- *type |= algt->type & CRYPTO_ALG_INTERNAL;
- *mask |= algt->mask & CRYPTO_ALG_INTERNAL;
+ *mask |= crypto_algt_inherited_mask(algt);
}
static int cryptd_init_instance(struct crypto_instance *inst,
@@ -364,6 +367,7 @@ static void cryptd_skcipher_free(struct skcipher_instance *inst)
static int cryptd_create_skcipher(struct crypto_template *tmpl,
struct rtattr **tb,
+ struct crypto_attr_type *algt,
struct cryptd_queue *queue)
{
struct skcipherd_instance_ctx *ctx;
@@ -373,10 +377,7 @@ static int cryptd_create_skcipher(struct crypto_template *tmpl,
u32 mask;
int err;
- type = 0;
- mask = CRYPTO_ALG_ASYNC;
-
- cryptd_check_internal(tb, &type, &mask);
+ cryptd_type_and_mask(algt, &type, &mask);
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
@@ -395,9 +396,8 @@ static int cryptd_create_skcipher(struct crypto_template *tmpl,
if (err)
goto err_free_inst;
- inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC |
- (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);
-
+ inst->alg.base.cra_flags |= CRYPTO_ALG_ASYNC |
+ (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);
inst->alg.ivsize = crypto_skcipher_alg_ivsize(alg);
inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg);
inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
@@ -633,16 +633,17 @@ static void cryptd_hash_free(struct ahash_instance *inst)
}
static int cryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
+ struct crypto_attr_type *algt,
struct cryptd_queue *queue)
{
struct hashd_instance_ctx *ctx;
struct ahash_instance *inst;
struct shash_alg *alg;
- u32 type = 0;
- u32 mask = 0;
+ u32 type;
+ u32 mask;
int err;
- cryptd_check_internal(tb, &type, &mask);
+ cryptd_type_and_mask(algt, &type, &mask);
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
@@ -661,10 +662,9 @@ static int cryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
if (err)
goto err_free_inst;
- inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC |
- (alg->base.cra_flags & (CRYPTO_ALG_INTERNAL |
+ inst->alg.halg.base.cra_flags |= CRYPTO_ALG_ASYNC |
+ (alg->base.cra_flags & (CRYPTO_ALG_INTERNAL|
CRYPTO_ALG_OPTIONAL_KEY));
-
inst->alg.halg.digestsize = alg->digestsize;
inst->alg.halg.statesize = alg->statesize;
inst->alg.halg.base.cra_ctxsize = sizeof(struct cryptd_hash_ctx);
@@ -820,16 +820,17 @@ static void cryptd_aead_free(struct aead_instance *inst)
static int cryptd_create_aead(struct crypto_template *tmpl,
struct rtattr **tb,
+ struct crypto_attr_type *algt,
struct cryptd_queue *queue)
{
struct aead_instance_ctx *ctx;
struct aead_instance *inst;
struct aead_alg *alg;
- u32 type = 0;
- u32 mask = CRYPTO_ALG_ASYNC;
+ u32 type;
+ u32 mask;
int err;
- cryptd_check_internal(tb, &type, &mask);
+ cryptd_type_and_mask(algt, &type, &mask);
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
@@ -848,8 +849,8 @@ static int cryptd_create_aead(struct crypto_template *tmpl,
if (err)
goto err_free_inst;
- inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC |
- (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);
+ inst->alg.base.cra_flags |= CRYPTO_ALG_ASYNC |
+ (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);
inst->alg.base.cra_ctxsize = sizeof(struct cryptd_aead_ctx);
inst->alg.ivsize = crypto_aead_alg_ivsize(alg);
@@ -884,11 +885,11 @@ static int cryptd_create(struct crypto_template *tmpl, struct rtattr **tb)
switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
case CRYPTO_ALG_TYPE_SKCIPHER:
- return cryptd_create_skcipher(tmpl, tb, &queue);
+ return cryptd_create_skcipher(tmpl, tb, algt, &queue);
case CRYPTO_ALG_TYPE_HASH:
- return cryptd_create_hash(tmpl, tb, &queue);
+ return cryptd_create_hash(tmpl, tb, algt, &queue);
case CRYPTO_ALG_TYPE_AEAD:
- return cryptd_create_aead(tmpl, tb, &queue);
+ return cryptd_create_aead(tmpl, tb, algt, &queue);
}
return -EINVAL;