crypto: add crypto_[un]register_shashes for [un]registering multiple shash entries at once

Add crypto_[un]register_shashes() to allow simplifying init/exit code of shash
crypto modules that register multiple algorithms.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/shash.c

@@ -629,6 +629,42 @@ int crypto_unregister_shash(struct shash_alg *alg)
 }
 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
 
+int crypto_register_shashes(struct shash_alg *algs, int count)
+{
+	int i, ret;
+
+	for (i = 0; i < count; i++) {
+		ret = crypto_register_shash(&algs[i]);
+		if (ret)
+			goto err;
+	}
+
+	return 0;
+
+err:
+	for (--i; i >= 0; --i)
+		crypto_unregister_shash(&algs[i]);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(crypto_register_shashes);
+
+int crypto_unregister_shashes(struct shash_alg *algs, int count)
+{
+	int i, ret;
+
+	for (i = count - 1; i >= 0; --i) {
+		ret = crypto_unregister_shash(&algs[i]);
+		if (ret)
+			pr_err("Failed to unregister %s %s: %d\n",
+			       algs[i].base.cra_driver_name,
+			       algs[i].base.cra_name, ret);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
+
 int shash_register_instance(struct crypto_template *tmpl,
 			    struct shash_instance *inst)
 {

include/crypto/internal/hash.h

@@ -83,6 +83,8 @@ struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask);
 
 int crypto_register_shash(struct shash_alg *alg);
 int crypto_unregister_shash(struct shash_alg *alg);
+int crypto_register_shashes(struct shash_alg *algs, int count);
+int crypto_unregister_shashes(struct shash_alg *algs, int count);
 int shash_register_instance(struct crypto_template *tmpl,
 			    struct shash_instance *inst);
 void shash_free_instance(struct crypto_instance *inst);