crypto: hash - Make setkey optional

Since most cryptographic hash algorithms have no keys, this patch
makes the setkey function optional for ahash and shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

2 files changed, 10 insertions, 1 deletions

diff --git a/crypto/ahash.c b/crypto/ahash.c
index 9f98956b17fc..ba5292d69ebd 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -162,6 +162,12 @@ static int ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
         return ahash->setkey(tfm, key, keylen);
 }
 
+static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
+                          unsigned int keylen)
+{
+        return -ENOSYS;
+}
+
 int crypto_ahash_import(struct ahash_request *req, const u8 *in)
 {
         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
@@ -194,7 +200,7 @@ static int crypto_init_ahash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
         crt->update = alg->update;
         crt->final  = alg->final;
         crt->digest = alg->digest;
-        crt->setkey = ahash_setkey;
+        crt->setkey = alg->setkey ? ahash_setkey : ahash_nosetkey;
         crt->digestsize = alg->digestsize;
 
         return 0;
diff --git a/crypto/shash.c b/crypto/shash.c
index 50d69a4e4b61..c9df367332ff 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -55,6 +55,9 @@ int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
         struct shash_alg *shash = crypto_shash_alg(tfm);
         unsigned long alignmask = crypto_shash_alignmask(tfm);
 
+        if (!shash->setkey)
+                return -ENOSYS;
+
         if ((unsigned long)key & alignmask)
                 return shash_setkey_unaligned(tfm, key, keylen);