[PATCH 5/6] crypto: ahash - Set default reqsize from ahash_alg

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

Add a reqsize field to struct ahash_alg and use it to set the
default reqsize so that algorithms with a static reqsize are
not forced to create an init_tfm function.

Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
---
 crypto/ahash.c        | 4 ++++
 include/crypto/hash.h | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/crypto/ahash.c b/crypto/ahash.c
index b1c468797990..52dd45d6aeab 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -875,6 +875,7 @@ static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 	struct ahash_alg *alg = crypto_ahash_alg(hash);
 
 	crypto_ahash_set_statesize(hash, alg->halg.statesize);
+	crypto_ahash_set_reqsize(hash, alg->reqsize);
 
 	if (tfm->__crt_alg->cra_type == &crypto_shash_type)
 		return crypto_init_ahash_using_shash(tfm);
@@ -1040,6 +1041,9 @@ static int ahash_prepare_alg(struct ahash_alg *alg)
 	if (alg->halg.statesize == 0)
 		return -EINVAL;
 
+	if (alg->reqsize && alg->reqsize < alg->halg.statesize)
+		return -EINVAL;
+
 	err = hash_prepare_alg(&alg->halg);
 	if (err)
 		return err;
diff --git a/include/crypto/hash.h b/include/crypto/hash.h
index 0cdadd48d068..db232070a317 100644
--- a/include/crypto/hash.h
+++ b/include/crypto/hash.h
@@ -135,6 +135,7 @@ struct ahash_request {
  *	      This is a counterpart to @init_tfm, used to remove
  *	      various changes set in @init_tfm.
  * @clone_tfm: Copy transform into new object, may allocate memory.
+ * @reqsize: Size of the request context.
  * @halg: see struct hash_alg_common
  */
 struct ahash_alg {
@@ -151,6 +152,8 @@ struct ahash_alg {
 	void (*exit_tfm)(struct crypto_ahash *tfm);
 	int (*clone_tfm)(struct crypto_ahash *dst, struct crypto_ahash *src);
 
+	unsigned int reqsize;
+
 	struct hash_alg_common halg;
 };
 
-- 
2.39.5