crypto: hash - Add crypto_ahash_has_setkey

commit a5596d6332787fd383b3b5427b41f94254430827 upstream.

This patch adds a way for ahash users to determine whether a key
is required by a crypto_ahash transform.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

3 files changed, 13 insertions, 2 deletions

diff --git a/crypto/ahash.c b/crypto/ahash.c
index 96c8e7cb680f..7fd8ecf71337 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -369,6 +369,7 @@ static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 	struct ahash_alg *alg = crypto_ahash_alg(hash);
 
 	hash->setkey = ahash_nosetkey;
+	hash->has_setkey = false;
 	hash->export = ahash_no_export;
 	hash->import = ahash_no_import;
 
@@ -381,8 +382,10 @@ static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 	hash->finup = alg->finup ?: ahash_def_finup;
 	hash->digest = alg->digest;
 
-	if (alg->setkey)
+	if (alg->setkey) {
 		hash->setkey = alg->setkey;
+		hash->has_setkey = true;
+	}
 	if (alg->export)
 		hash->export = alg->export;
 	if (alg->import)
diff --git a/crypto/shash.c b/crypto/shash.c
index f507294f2811..d15f35019c4b 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -354,8 +354,10 @@ int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
 	crt->finup = shash_async_finup;
 	crt->digest = shash_async_digest;
 
-	if (alg->setkey)
+	if (alg->setkey) {
 		crt->setkey = shash_async_setkey;
+		crt->has_setkey = true;
+	}
 	if (alg->export)
 		crt->export = shash_async_export;
 	if (alg->import)
diff --git a/include/crypto/hash.h b/include/crypto/hash.h
index 26cb1eb16f4c..c8c79878c082 100644
--- a/include/crypto/hash.h
+++ b/include/crypto/hash.h
@@ -94,6 +94,7 @@ struct crypto_ahash {
 		      unsigned int keylen);
 
 	unsigned int reqsize;
+	bool has_setkey;
 	struct crypto_tfm base;
 };
 
@@ -181,6 +182,11 @@ static inline void *ahash_request_ctx(struct ahash_request *req)
 
 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 			unsigned int keylen);
+static inline bool crypto_ahash_has_setkey(struct crypto_ahash *tfm)
+{
+	return tfm->has_setkey;
+}
+
 int crypto_ahash_finup(struct ahash_request *req);
 int crypto_ahash_final(struct ahash_request *req);
 int crypto_ahash_digest(struct ahash_request *req);