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>

1 files changed, 3 insertions, 0 deletions

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);