[CRYPTO] api: Add common instance initialisation code
This patch adds the helpers crypto_get_attr_alg and crypto_alloc_instance
which can be used by simple one-argument templates like hmac to process
input parameters and allocate instances.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/algapi.c b/crypto/algapi.c
index 36c4f1bd..c915300 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -16,6 +16,7 @@
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
+#include <linux/rtnetlink.h>
#include <linux/string.h>
#include "internal.h"
@@ -415,6 +416,58 @@
}
EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
+struct crypto_alg *crypto_get_attr_alg(void *param, unsigned int len,
+ u32 type, u32 mask)
+{
+ struct rtattr *rta = param;
+ struct crypto_attr_alg *alga;
+
+ if (!RTA_OK(rta, len))
+ return ERR_PTR(-EBADR);
+ if (rta->rta_type != CRYPTOA_ALG || RTA_PAYLOAD(rta) < sizeof(*alga))
+ return ERR_PTR(-EINVAL);
+
+ alga = RTA_DATA(rta);
+ alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;
+
+ return crypto_alg_mod_lookup(alga->name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_get_attr_alg);
+
+struct crypto_instance *crypto_alloc_instance(const char *name,
+ struct crypto_alg *alg)
+{
+ struct crypto_instance *inst;
+ struct crypto_spawn *spawn;
+ int err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+ if (!inst)
+ return ERR_PTR(-ENOMEM);
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
+ alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+ name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ spawn = crypto_instance_ctx(inst);
+ err = crypto_init_spawn(spawn, alg, inst);
+
+ if (err)
+ goto err_free_inst;
+
+ return inst;
+
+err_free_inst:
+ kfree(inst);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_instance);
+
static int __init crypto_algapi_init(void)
{
crypto_init_proc();