[CRYPTO] api: Added spawns
[linux-2.6.git] / crypto / algapi.c
index a65c6cc..36c4f1b 100644 (file)
  *
  */
 
+#include <linux/err.h>
 #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);
+
+void crypto_larval_error(const char *name, u32 type, u32 mask)
+{
+       struct crypto_alg *alg;
+
+       down_read(&crypto_alg_sem);
+       alg = __crypto_alg_lookup(name, type, mask);
+       up_read(&crypto_alg_sem);
+
+       if (alg) {
+               if (crypto_is_larval(alg)) {
+                       struct crypto_larval *larval = (void *)alg;
+                       complete(&larval->completion);
+               }
+               crypto_mod_put(alg);
+       }
+}
+EXPORT_SYMBOL_GPL(crypto_larval_error);
+
 static inline int crypto_set_driver_name(struct crypto_alg *alg)
 {
        static const char suffix[] = "-generic";
@@ -35,11 +57,8 @@ static inline int crypto_set_driver_name(struct crypto_alg *alg)
        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 +70,161 @@ int crypto_register_alg(struct crypto_alg *alg)
 
        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 void crypto_destroy_instance(struct crypto_alg *alg)
+{
+       struct crypto_instance *inst = (void *)alg;
+       struct crypto_template *tmpl = inst->tmpl;
+
+       tmpl->free(inst);
+       crypto_tmpl_put(tmpl);
+}
+
+static void crypto_remove_spawns(struct list_head *spawns,
+                                struct list_head *list)
+{
+       struct crypto_spawn *spawn, *n;
+
+       list_for_each_entry_safe(spawn, n, spawns, list) {
+               struct crypto_instance *inst = spawn->inst;
+               struct crypto_template *tmpl = inst->tmpl;
+
+               list_del_init(&spawn->list);
+               spawn->alg = NULL;
+
+               if (crypto_is_dead(&inst->alg))
+                       continue;
+
+               inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
+               if (!tmpl || !crypto_tmpl_get(tmpl))
+                       continue;
+
+               crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg);
+               list_move(&inst->alg.cra_list, list);
+               hlist_del(&inst->list);
+               inst->alg.cra_destroy = crypto_destroy_instance;
+
+               if (!list_empty(&inst->alg.cra_users)) {
+                       if (&n->list == spawns)
+                               n = list_entry(inst->alg.cra_users.next,
+                                              typeof(*n), list);
+                       __list_splice(&inst->alg.cra_users, spawns->prev);
+               }
+       }
+}
+
+static int __crypto_register_alg(struct crypto_alg *alg,
+                                struct list_head *list)
+{
+       struct crypto_alg *q;
+       int ret = -EAGAIN;
+
+       if (crypto_is_dead(alg))
+               goto out;
+
+       INIT_LIST_HEAD(&alg->cra_users);
+
+       ret = -EEXIST;
+
+       atomic_set(&alg->cra_refcnt, 1);
        list_for_each_entry(q, &crypto_alg_list, cra_list) {
-               if (q == alg) {
-                       ret = -EEXIST;
+               if (q == alg)
                        goto out;
+
+               if (crypto_is_moribund(q))
+                       continue;
+
+               if (crypto_is_larval(q)) {
+                       struct crypto_larval *larval = (void *)q;
+
+                       if (strcmp(alg->cra_name, q->cra_name) &&
+                           strcmp(alg->cra_driver_name, q->cra_name))
+                               continue;
+
+                       if (larval->adult)
+                               continue;
+                       if ((q->cra_flags ^ alg->cra_flags) & larval->mask)
+                               continue;
+                       if (!crypto_mod_get(alg))
+                               continue;
+
+                       larval->adult = alg;
+                       complete(&larval->completion);
+                       continue;
                }
+
+               if (strcmp(alg->cra_name, q->cra_name))
+                       continue;
+
+               if (strcmp(alg->cra_driver_name, q->cra_driver_name) &&
+                   q->cra_priority > alg->cra_priority)
+                       continue;
+
+               crypto_remove_spawns(&q->cra_users, list);
        }
        
        list_add(&alg->cra_list, &crypto_alg_list);
-       atomic_set(&alg->cra_refcnt, 1);
+
+       crypto_notify(CRYPTO_MSG_ALG_REGISTER, alg);
+       ret = 0;
+
 out:   
-       up_write(&crypto_alg_sem);
        return ret;
 }
+
+static void crypto_remove_final(struct list_head *list)
+{
+       struct crypto_alg *alg;
+       struct crypto_alg *n;
+
+       list_for_each_entry_safe(alg, n, list, cra_list) {
+               list_del_init(&alg->cra_list);
+               crypto_alg_put(alg);
+       }
+}
+
+int crypto_register_alg(struct crypto_alg *alg)
+{
+       LIST_HEAD(list);
+       int err;
+
+       err = crypto_check_alg(alg);
+       if (err)
+               return err;
+
+       down_write(&crypto_alg_sem);
+       err = __crypto_register_alg(alg, &list);
+       up_write(&crypto_alg_sem);
+
+       crypto_remove_final(&list);
+       return err;
+}
 EXPORT_SYMBOL_GPL(crypto_register_alg);
 
+static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
+{
+       if (unlikely(list_empty(&alg->cra_list)))
+               return -ENOENT;
+
+       alg->cra_flags |= CRYPTO_ALG_DEAD;
+
+       crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
+       list_del_init(&alg->cra_list);
+       crypto_remove_spawns(&alg->cra_users, list);
+
+       return 0;
+}
+
 int crypto_unregister_alg(struct crypto_alg *alg)
 {
-       int ret = -ENOENT;
-       struct crypto_alg *q;
+       int ret;
+       LIST_HEAD(list);
        
        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;
-               }
-       }
-out:   
+       ret = crypto_remove_alg(alg, &list);
        up_write(&crypto_alg_sem);
 
        if (ret)
@@ -96,10 +234,187 @@ out:
        if (alg->cra_destroy)
                alg->cra_destroy(alg);
 
+       crypto_remove_final(&list);
        return 0;
 }
 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);
+       crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl);
+       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;
+       LIST_HEAD(users);
+
+       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) {
+               int err = crypto_remove_alg(&inst->alg, &users);
+               BUG_ON(err);
+       }
+
+       crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl);
+
+       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);
+       }
+       crypto_remove_final(&users);
+}
+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)
+{
+       LIST_HEAD(list);
+       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, &list);
+       if (err)
+               goto unlock;
+
+       hlist_add_head(&inst->list, &tmpl->instances);
+       inst->tmpl = tmpl;
+
+unlock:
+       up_write(&crypto_alg_sem);
+
+       crypto_remove_final(&list);
+
+err:
+       return err;
+}
+EXPORT_SYMBOL_GPL(crypto_register_instance);
+
+int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
+                     struct crypto_instance *inst)
+{
+       int err = -EAGAIN;
+
+       spawn->inst = inst;
+
+       down_write(&crypto_alg_sem);
+       if (!crypto_is_moribund(alg)) {
+               list_add(&spawn->list, &alg->cra_users);
+               spawn->alg = alg;
+               err = 0;
+       }
+       up_write(&crypto_alg_sem);
+
+       return err;
+}
+EXPORT_SYMBOL_GPL(crypto_init_spawn);
+
+void crypto_drop_spawn(struct crypto_spawn *spawn)
+{
+       down_write(&crypto_alg_sem);
+       list_del(&spawn->list);
+       up_write(&crypto_alg_sem);
+}
+EXPORT_SYMBOL_GPL(crypto_drop_spawn);
+
+struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn)
+{
+       struct crypto_alg *alg;
+       struct crypto_alg *alg2;
+       struct crypto_tfm *tfm;
+
+       down_read(&crypto_alg_sem);
+       alg = spawn->alg;
+       alg2 = alg;
+       if (alg2)
+               alg2 = crypto_mod_get(alg2);
+       up_read(&crypto_alg_sem);
+
+       if (!alg2) {
+               if (alg)
+                       crypto_shoot_alg(alg);
+               return ERR_PTR(-EAGAIN);
+       }
+
+       tfm = __crypto_alloc_tfm(alg, 0);
+       if (IS_ERR(tfm))
+               crypto_mod_put(alg);
+
+       return tfm;
+}
+EXPORT_SYMBOL_GPL(crypto_spawn_tfm);
+
+int crypto_register_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_register(&crypto_chain, nb);
+}
+EXPORT_SYMBOL_GPL(crypto_register_notifier);
+
+int crypto_unregister_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_unregister(&crypto_chain, nb);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_notifier);
+
 static int __init crypto_algapi_init(void)
 {
        crypto_init_proc();