[CRYPTO] api: Add template registration
A crypto_template generates a crypto_alg object when given a set of
parameters. this patch adds the basic data structure fo templates
and code to handle their registration/deregistration.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/crypto/algapi.c b/crypto/algapi.c
index a65c6cc..232b37d 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -13,11 +13,14 @@
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/list.h>
#include <linux/module.h>
#include <linux/string.h>
#include "internal.h"
+static LIST_HEAD(crypto_template_list);
+
static inline int crypto_set_driver_name(struct crypto_alg *alg)
{
static const char suffix[] = "-generic";
@@ -35,11 +38,8 @@
return 0;
}
-int crypto_register_alg(struct crypto_alg *alg)
+static int crypto_check_alg(struct crypto_alg *alg)
{
- int ret;
- struct crypto_alg *q;
-
if (alg->cra_alignmask & (alg->cra_alignmask + 1))
return -EINVAL;
@@ -51,42 +51,52 @@
if (alg->cra_priority < 0)
return -EINVAL;
-
- ret = crypto_set_driver_name(alg);
- if (unlikely(ret))
- return ret;
- down_write(&crypto_alg_sem);
-
+ return crypto_set_driver_name(alg);
+}
+
+static int __crypto_register_alg(struct crypto_alg *alg)
+{
+ struct crypto_alg *q;
+ int ret = -EEXIST;
+
list_for_each_entry(q, &crypto_alg_list, cra_list) {
- if (q == alg) {
- ret = -EEXIST;
+ if (q == alg)
goto out;
- }
}
list_add(&alg->cra_list, &crypto_alg_list);
atomic_set(&alg->cra_refcnt, 1);
+ ret = 0;
out:
- up_write(&crypto_alg_sem);
return ret;
}
+
+int crypto_register_alg(struct crypto_alg *alg)
+{
+ int err;
+
+ err = crypto_check_alg(alg);
+ if (err)
+ return err;
+
+ down_write(&crypto_alg_sem);
+ err = __crypto_register_alg(alg);
+ up_write(&crypto_alg_sem);
+
+ return err;
+}
EXPORT_SYMBOL_GPL(crypto_register_alg);
int crypto_unregister_alg(struct crypto_alg *alg)
{
int ret = -ENOENT;
- struct crypto_alg *q;
down_write(&crypto_alg_sem);
- list_for_each_entry(q, &crypto_alg_list, cra_list) {
- if (alg == q) {
- list_del(&alg->cra_list);
- ret = 0;
- goto out;
- }
+ if (likely(!list_empty(&alg->cra_list))) {
+ list_del_init(&alg->cra_list);
+ ret = 0;
}
-out:
up_write(&crypto_alg_sem);
if (ret)
@@ -100,6 +110,108 @@
}
EXPORT_SYMBOL_GPL(crypto_unregister_alg);
+int crypto_register_template(struct crypto_template *tmpl)
+{
+ struct crypto_template *q;
+ int err = -EEXIST;
+
+ down_write(&crypto_alg_sem);
+
+ list_for_each_entry(q, &crypto_template_list, list) {
+ if (q == tmpl)
+ goto out;
+ }
+
+ list_add(&tmpl->list, &crypto_template_list);
+ err = 0;
+out:
+ up_write(&crypto_alg_sem);
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_register_template);
+
+void crypto_unregister_template(struct crypto_template *tmpl)
+{
+ struct crypto_instance *inst;
+ struct hlist_node *p, *n;
+ struct hlist_head *list;
+
+ down_write(&crypto_alg_sem);
+
+ BUG_ON(list_empty(&tmpl->list));
+ list_del_init(&tmpl->list);
+
+ list = &tmpl->instances;
+ hlist_for_each_entry(inst, p, list, list) {
+ BUG_ON(list_empty(&inst->alg.cra_list));
+ list_del_init(&inst->alg.cra_list);
+ }
+
+ up_write(&crypto_alg_sem);
+
+ hlist_for_each_entry_safe(inst, p, n, list, list) {
+ BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1);
+ tmpl->free(inst);
+ }
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_template);
+
+static struct crypto_template *__crypto_lookup_template(const char *name)
+{
+ struct crypto_template *q, *tmpl = NULL;
+
+ down_read(&crypto_alg_sem);
+ list_for_each_entry(q, &crypto_template_list, list) {
+ if (strcmp(q->name, name))
+ continue;
+ if (unlikely(!crypto_tmpl_get(q)))
+ continue;
+
+ tmpl = q;
+ break;
+ }
+ up_read(&crypto_alg_sem);
+
+ return tmpl;
+}
+
+struct crypto_template *crypto_lookup_template(const char *name)
+{
+ return try_then_request_module(__crypto_lookup_template(name), name);
+}
+EXPORT_SYMBOL_GPL(crypto_lookup_template);
+
+int crypto_register_instance(struct crypto_template *tmpl,
+ struct crypto_instance *inst)
+{
+ int err = -EINVAL;
+
+ if (inst->alg.cra_destroy)
+ goto err;
+
+ err = crypto_check_alg(&inst->alg);
+ if (err)
+ goto err;
+
+ inst->alg.cra_module = tmpl->module;
+
+ down_write(&crypto_alg_sem);
+
+ err = __crypto_register_alg(&inst->alg);
+ if (err)
+ goto unlock;
+
+ hlist_add_head(&inst->list, &tmpl->instances);
+ inst->tmpl = tmpl;
+
+unlock:
+ up_write(&crypto_alg_sem);
+
+err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_register_instance);
+
static int __init crypto_algapi_init(void)
{
crypto_init_proc();
diff --git a/crypto/internal.h b/crypto/internal.h
index 26f47d3..c3ab4a9 100644
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -19,11 +19,15 @@
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/list.h>
+#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include <asm/kmap_types.h>
+struct crypto_instance;
+struct crypto_template;
+
extern struct list_head crypto_alg_list;
extern struct rw_semaphore crypto_alg_sem;
@@ -112,5 +116,18 @@
void crypto_exit_cipher_ops(struct crypto_tfm *tfm);
void crypto_exit_compress_ops(struct crypto_tfm *tfm);
+int crypto_register_instance(struct crypto_template *tmpl,
+ struct crypto_instance *inst);
+
+static inline int crypto_tmpl_get(struct crypto_template *tmpl)
+{
+ return try_module_get(tmpl->module);
+}
+
+static inline void crypto_tmpl_put(struct crypto_template *tmpl)
+{
+ module_put(tmpl->module);
+}
+
#endif /* _CRYPTO_INTERNAL_H */
diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index ed68d49..ffec530 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -14,5 +14,36 @@
#include <linux/crypto.h>
+struct module;
+
+struct crypto_instance {
+ struct crypto_alg alg;
+
+ struct crypto_template *tmpl;
+ struct hlist_node list;
+
+ void *__ctx[] CRYPTO_MINALIGN_ATTR;
+};
+
+struct crypto_template {
+ struct list_head list;
+ struct hlist_head instances;
+ struct module *module;
+
+ struct crypto_instance *(*alloc)(void *param, unsigned int len);
+ void (*free)(struct crypto_instance *inst);
+
+ char name[CRYPTO_MAX_ALG_NAME];
+};
+
+int crypto_register_template(struct crypto_template *tmpl);
+void crypto_unregister_template(struct crypto_template *tmpl);
+struct crypto_template *crypto_lookup_template(const char *name);
+
+static inline void *crypto_instance_ctx(struct crypto_instance *inst)
+{
+ return inst->__ctx;
+}
+
#endif /* _CRYPTO_ALGAPI_H */