path: root/include
diff options
authorEric Biggers <>2020-07-09 23:20:38 -0700
committerHerbert Xu <>2020-07-16 21:49:08 +1000
commit7bcb2c99f8ed032cfb3f5596b4dccac6b1f501df (patch)
tree7d8e914c0368036db8f1d99a923387833546330a /include
parent4688111e78ed432b19c3cd6de545c83c47dc28b3 (diff)
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 <> ( Signed-off-by: Eric Biggers <> Signed-off-by: Herbert Xu <>
Diffstat (limited to 'include')
1 files changed, 16 insertions, 7 deletions
diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index 00a9cf98debe..da64c37482b4 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -116,7 +116,7 @@ struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
-int crypto_check_attr_type(struct rtattr **tb, u32 type);
+int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
const char *crypto_attr_alg_name(struct rtattr *rta);
int crypto_attr_u32(struct rtattr *rta, u32 *num);
int crypto_inst_setname(struct crypto_instance *inst, const char *name,
@@ -235,18 +235,27 @@ static inline struct crypto_async_request *crypto_get_backlog(
container_of(queue->backlog, struct crypto_async_request, list);
-static inline int crypto_requires_off(u32 type, u32 mask, u32 off)
+static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
- return (type ^ off) & mask & off;
+ return (algt->type ^ off) & algt->mask & off;
- * Returns CRYPTO_ALG_ASYNC if type/mask requires the use of sync algorithms.
- * Otherwise returns zero.
+ * When an algorithm uses another algorithm (e.g., if it's an instance of a
+ * template), these are the flags that should always be set on the "outer"
+ * algorithm if any "inner" algorithm has them set.
-static inline int crypto_requires_sync(u32 type, u32 mask)
+ * Given the type and mask that specify the flags restrictions on a template
+ * instance being created, return the mask that should be passed to
+ * crypto_grab_*() (along with type=0) to honor any request the user made to
+ * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
+ */
+static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
- return crypto_requires_off(type, mask, CRYPTO_ALG_ASYNC);
+ return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);