// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   * Cryptographic API for algorithms (i.e., low-level API).
   *
   * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>

   */

  #include <crypto/algapi.h>

  #include <linux/err.h>

  #include <linux/errno.h>

  #include <linux/fips.h>

  #include <linux/init.h>
  #include <linux/kernel.h>

  #include <linux/list.h>

  #include <linux/module.h>

  #include <linux/rtnetlink.h>

  #include <linux/slab.h>

  #include <linux/string.h>
  
  #include "internal.h"

  static LIST_HEAD(crypto_template_list);

  static inline void crypto_check_module_sig(struct module *mod)
  {

  	if (fips_enabled && mod && !module_sig_ok(mod))

  		panic("Module %s signature verification failed in FIPS mode
  ",

  		      module_name(mod));

  }

  static int crypto_check_alg(struct crypto_alg *alg)

  {

  	crypto_check_module_sig(alg->cra_module);

  	if (!alg->cra_name[0] || !alg->cra_driver_name[0])
  		return -EINVAL;

  	if (alg->cra_alignmask & (alg->cra_alignmask + 1))
  		return -EINVAL;

  	/* General maximums for all algs. */
  	if (alg->cra_alignmask > MAX_ALGAPI_ALIGNMASK)

  		return -EINVAL;

  	if (alg->cra_blocksize > MAX_ALGAPI_BLOCKSIZE)
  		return -EINVAL;
  
  	/* Lower maximums for specific alg types. */

  	if (!alg->cra_type && (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
  			       CRYPTO_ALG_TYPE_CIPHER) {
  		if (alg->cra_alignmask > MAX_CIPHER_ALIGNMASK)
  			return -EINVAL;
  
  		if (alg->cra_blocksize > MAX_CIPHER_BLOCKSIZE)
  			return -EINVAL;
  	}

  	if (alg->cra_priority < 0)
  		return -EINVAL;

  	refcount_set(&alg->cra_refcnt, 1);

  	return 0;

  }

  static void crypto_free_instance(struct crypto_instance *inst)
  {

  	inst->alg.cra_type->free(inst);
  }

  static void crypto_destroy_instance(struct crypto_alg *alg)
  {
  	struct crypto_instance *inst = (void *)alg;
  	struct crypto_template *tmpl = inst->tmpl;

  	crypto_free_instance(inst);

  	crypto_tmpl_put(tmpl);
  }

  /*
   * This function adds a spawn to the list secondary_spawns which
   * will be used at the end of crypto_remove_spawns to unregister
   * instances, unless the spawn happens to be one that is depended
   * on by the new algorithm (nalg in crypto_remove_spawns).
   *
   * This function is also responsible for resurrecting any algorithms
   * in the dependency chain of nalg by unsetting n->dead.
   */

  static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
  					    struct list_head *stack,
  					    struct list_head *top,
  					    struct list_head *secondary_spawns)
  {
  	struct crypto_spawn *spawn, *n;

  	spawn = list_first_entry_or_null(stack, struct crypto_spawn, list);
  	if (!spawn)

  		return NULL;

  	n = list_prev_entry(spawn, list);
  	list_move(&spawn->list, secondary_spawns);

  	if (list_is_last(&n->list, stack))
  		return top;

  	n = list_next_entry(n, list);
  	if (!spawn->dead)
  		n->dead = false;

  	return &n->inst->alg.cra_users;

  }

  static void crypto_remove_instance(struct crypto_instance *inst,
  				   struct list_head *list)

  {

  	struct crypto_template *tmpl = inst->tmpl;

  	if (crypto_is_dead(&inst->alg))
  		return;

  	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;

  	if (!tmpl || !crypto_tmpl_get(tmpl))
  		return;

  	list_move(&inst->alg.cra_list, list);
  	hlist_del(&inst->list);
  	inst->alg.cra_destroy = crypto_destroy_instance;

  	BUG_ON(!list_empty(&inst->alg.cra_users));

  }

  /*
   * Given an algorithm alg, remove all algorithms that depend on it
   * through spawns.  If nalg is not null, then exempt any algorithms
   * that is depended on by nalg.  This is useful when nalg itself
   * depends on alg.
   */

  void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
  			  struct crypto_alg *nalg)

  {

  	u32 new_type = (nalg ?: alg)->cra_flags;

  	struct crypto_spawn *spawn, *n;
  	LIST_HEAD(secondary_spawns);

  	struct list_head *spawns;
  	LIST_HEAD(stack);
  	LIST_HEAD(top);

  	spawns = &alg->cra_users;

  	list_for_each_entry_safe(spawn, n, spawns, list) {
  		if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)

  			continue;

  		list_move(&spawn->list, &top);

  	}

  	/*
  	 * Perform a depth-first walk starting from alg through
  	 * the cra_users tree.  The list stack records the path
  	 * from alg to the current spawn.
  	 */

  	spawns = ⊤
  	do {
  		while (!list_empty(spawns)) {
  			struct crypto_instance *inst;
  
  			spawn = list_first_entry(spawns, struct crypto_spawn,
  						 list);
  			inst = spawn->inst;

  			list_move(&spawn->list, &stack);

  			spawn->dead = !spawn->registered || &inst->alg != nalg;
  
  			if (!spawn->registered)
  				break;
  
  			BUG_ON(&inst->alg == alg);

  
  			if (&inst->alg == nalg)
  				break;

  			spawns = &inst->alg.cra_users;

  
  			/*

  			 * Even if spawn->registered is true, the
  			 * instance itself may still be unregistered.
  			 * This is because it may have failed during
  			 * registration.  Therefore we still need to
  			 * make the following test.
  			 *

  			 * We may encounter an unregistered instance here, since
  			 * an instance's spawns are set up prior to the instance
  			 * being registered.  An unregistered instance will have
  			 * NULL ->cra_users.next, since ->cra_users isn't
  			 * properly initialized until registration.  But an
  			 * unregistered instance cannot have any users, so treat
  			 * it the same as ->cra_users being empty.
  			 */
  			if (spawns->next == NULL)
  				break;

  		}
  	} while ((spawns = crypto_more_spawns(alg, &stack, &top,
  					      &secondary_spawns)));

  	/*
  	 * Remove all instances that are marked as dead.  Also
  	 * complete the resurrection of the others by moving them
  	 * back to the cra_users list.
  	 */

  	list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {

  		if (!spawn->dead)

  			list_move(&spawn->list, &spawn->alg->cra_users);

  		else if (spawn->registered)

  			crypto_remove_instance(spawn->inst, list);

  	}
  }

  EXPORT_SYMBOL_GPL(crypto_remove_spawns);

  static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg)

  {
  	struct crypto_alg *q;

  	struct crypto_larval *larval;

  	int ret = -EAGAIN;
  
  	if (crypto_is_dead(alg))

  		goto err;

  
  	INIT_LIST_HEAD(&alg->cra_users);

  	/* No cheating! */
  	alg->cra_flags &= ~CRYPTO_ALG_TESTED;

  	ret = -EEXIST;

  	list_for_each_entry(q, &crypto_alg_list, cra_list) {

  		if (q == alg)

  			goto err;

  		if (crypto_is_moribund(q))
  			continue;

  		if (crypto_is_larval(q)) {
  			if (!strcmp(alg->cra_driver_name, q->cra_driver_name))
  				goto err;
  			continue;
  		}
  
  		if (!strcmp(q->cra_driver_name, alg->cra_name) ||
  		    !strcmp(q->cra_name, alg->cra_driver_name))
  			goto err;
  	}
  
  	larval = crypto_larval_alloc(alg->cra_name,
  				     alg->cra_flags | CRYPTO_ALG_TESTED, 0);
  	if (IS_ERR(larval))
  		goto out;
  
  	ret = -ENOENT;
  	larval->adult = crypto_mod_get(alg);
  	if (!larval->adult)
  		goto free_larval;

  	refcount_set(&larval->alg.cra_refcnt, 1);

  	memcpy(larval->alg.cra_driver_name, alg->cra_driver_name,
  	       CRYPTO_MAX_ALG_NAME);
  	larval->alg.cra_priority = alg->cra_priority;
  
  	list_add(&alg->cra_list, &crypto_alg_list);
  	list_add(&larval->alg.cra_list, &crypto_alg_list);

  	crypto_stats_init(alg);

  out:

  	return larval;
  
  free_larval:
  	kfree(larval);
  err:
  	larval = ERR_PTR(ret);
  	goto out;
  }
  
  void crypto_alg_tested(const char *name, int err)
  {
  	struct crypto_larval *test;
  	struct crypto_alg *alg;
  	struct crypto_alg *q;
  	LIST_HEAD(list);

  	bool best;

  
  	down_write(&crypto_alg_sem);
  	list_for_each_entry(q, &crypto_alg_list, cra_list) {

  		if (crypto_is_moribund(q) || !crypto_is_larval(q))

  			continue;
  
  		test = (struct crypto_larval *)q;
  
  		if (!strcmp(q->cra_driver_name, name))
  			goto found;
  	}

  	pr_err("alg: Unexpected test result for %s: %d
  ", name, err);

  	goto unlock;
  
  found:

  	q->cra_flags |= CRYPTO_ALG_DEAD;

  	alg = test->adult;
  	if (err || list_empty(&alg->cra_list))
  		goto complete;
  
  	alg->cra_flags |= CRYPTO_ALG_TESTED;

  	/* Only satisfy larval waiters if we are the best. */
  	best = true;
  	list_for_each_entry(q, &crypto_alg_list, cra_list) {
  		if (crypto_is_moribund(q) || !crypto_is_larval(q))
  			continue;
  
  		if (strcmp(alg->cra_name, q->cra_name))
  			continue;
  
  		if (q->cra_priority > alg->cra_priority) {
  			best = false;
  			break;
  		}
  	}

  	list_for_each_entry(q, &crypto_alg_list, cra_list) {
  		if (q == alg)
  			continue;

  
  		if (crypto_is_moribund(q))
  			continue;
  
  		if (crypto_is_larval(q)) {

  			struct crypto_larval *larval = (void *)q;

  			/*
  			 * Check to see if either our generic name or
  			 * specific name can satisfy the name requested
  			 * by the larval entry 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 (best && crypto_mod_get(alg))
  				larval->adult = alg;
  			else
  				larval->adult = ERR_PTR(-EAGAIN);

  			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, &list, alg);

  	}

  complete:
  	complete_all(&test->completion);

  unlock:
  	up_write(&crypto_alg_sem);
  
  	crypto_remove_final(&list);

  }

  EXPORT_SYMBOL_GPL(crypto_alg_tested);

  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);
  	}
  }

  EXPORT_SYMBOL_GPL(crypto_remove_final);

  static void crypto_wait_for_test(struct crypto_larval *larval)
  {
  	int err;
  
  	err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult);
  	if (err != NOTIFY_STOP) {
  		if (WARN_ON(err != NOTIFY_DONE))
  			goto out;
  		crypto_alg_tested(larval->alg.cra_driver_name, 0);
  	}

  	err = wait_for_completion_killable(&larval->completion);

  	WARN_ON(err);

  	if (!err)

  		crypto_notify(CRYPTO_MSG_ALG_LOADED, larval);

  
  out:
  	crypto_larval_kill(&larval->alg);
  }

  int crypto_register_alg(struct crypto_alg *alg)
  {

  	struct crypto_larval *larval;

  	int err;

  	alg->cra_flags &= ~CRYPTO_ALG_DEAD;

  	err = crypto_check_alg(alg);
  	if (err)
  		return err;
  
  	down_write(&crypto_alg_sem);

  	larval = __crypto_register_alg(alg);

  	up_write(&crypto_alg_sem);

  	if (IS_ERR(larval))
  		return PTR_ERR(larval);
  
  	crypto_wait_for_test(larval);
  	return 0;

  }

  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;

  	list_del_init(&alg->cra_list);

  	crypto_remove_spawns(alg, list, NULL);

  
  	return 0;
  }

  void crypto_unregister_alg(struct crypto_alg *alg)

  {

  	int ret;
  	LIST_HEAD(list);

  	down_write(&crypto_alg_sem);

  	ret = crypto_remove_alg(alg, &list);

  	up_write(&crypto_alg_sem);

  	if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name))
  		return;

  	BUG_ON(refcount_read(&alg->cra_refcnt) != 1);

  	if (alg->cra_destroy)
  		alg->cra_destroy(alg);

  	crypto_remove_final(&list);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_alg);

  int crypto_register_algs(struct crypto_alg *algs, int count)
  {
  	int i, ret;
  
  	for (i = 0; i < count; i++) {
  		ret = crypto_register_alg(&algs[i]);
  		if (ret)
  			goto err;
  	}
  
  	return 0;
  
  err:
  	for (--i; i >= 0; --i)
  		crypto_unregister_alg(&algs[i]);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(crypto_register_algs);

  void crypto_unregister_algs(struct crypto_alg *algs, int count)

  {

  	int i;

  	for (i = 0; i < count; i++)
  		crypto_unregister_alg(&algs[i]);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_algs);

  int crypto_register_template(struct crypto_template *tmpl)
  {
  	struct crypto_template *q;
  	int err = -EEXIST;
  
  	down_write(&crypto_alg_sem);

  	crypto_check_module_sig(tmpl->module);

  	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);

  int crypto_register_templates(struct crypto_template *tmpls, int count)
  {
  	int i, err;
  
  	for (i = 0; i < count; i++) {
  		err = crypto_register_template(&tmpls[i]);
  		if (err)
  			goto out;
  	}
  	return 0;
  
  out:
  	for (--i; i >= 0; --i)
  		crypto_unregister_template(&tmpls[i]);
  	return err;
  }
  EXPORT_SYMBOL_GPL(crypto_register_templates);

  void crypto_unregister_template(struct crypto_template *tmpl)
  {
  	struct crypto_instance *inst;

  	struct hlist_node *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, list, list) {

  		int err = crypto_remove_alg(&inst->alg, &users);

  		BUG_ON(err);

  	}
  
  	up_write(&crypto_alg_sem);

  	hlist_for_each_entry_safe(inst, n, list, list) {

  		BUG_ON(refcount_read(&inst->alg.cra_refcnt) != 1);

  		crypto_free_instance(inst);

  	}

  	crypto_remove_final(&users);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_template);

  void crypto_unregister_templates(struct crypto_template *tmpls, int count)
  {
  	int i;
  
  	for (i = count - 1; i >= 0; --i)
  		crypto_unregister_template(&tmpls[i]);
  }
  EXPORT_SYMBOL_GPL(crypto_unregister_templates);

  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),
  				       "crypto-%s", name);

  }
  EXPORT_SYMBOL_GPL(crypto_lookup_template);
  
  int crypto_register_instance(struct crypto_template *tmpl,
  			     struct crypto_instance *inst)
  {

  	struct crypto_larval *larval;

  	struct crypto_spawn *spawn;

  	int err;

  	err = crypto_check_alg(&inst->alg);
  	if (err)

  		return err;

  	inst->alg.cra_module = tmpl->module;

  	inst->alg.cra_flags |= CRYPTO_ALG_INSTANCE;

  
  	down_write(&crypto_alg_sem);

  	larval = ERR_PTR(-EAGAIN);
  	for (spawn = inst->spawns; spawn;) {
  		struct crypto_spawn *next;
  
  		if (spawn->dead)
  			goto unlock;
  
  		next = spawn->next;
  		spawn->inst = inst;
  		spawn->registered = true;

  		crypto_mod_put(spawn->alg);

  
  		spawn = next;
  	}

  	larval = __crypto_register_alg(&inst->alg);
  	if (IS_ERR(larval))

  		goto unlock;
  
  	hlist_add_head(&inst->list, &tmpl->instances);
  	inst->tmpl = tmpl;
  
  unlock:
  	up_write(&crypto_alg_sem);

  	err = PTR_ERR(larval);
  	if (IS_ERR(larval))
  		goto err;
  
  	crypto_wait_for_test(larval);
  	err = 0;

  err:
  	return err;
  }
  EXPORT_SYMBOL_GPL(crypto_register_instance);

  void crypto_unregister_instance(struct crypto_instance *inst)

  {

  	LIST_HEAD(list);

  	down_write(&crypto_alg_sem);

  	crypto_remove_spawns(&inst->alg, &list, NULL);

  	crypto_remove_instance(inst, &list);

  
  	up_write(&crypto_alg_sem);

  	crypto_remove_final(&list);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_instance);

  int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
  		      const char *name, u32 type, u32 mask)

  {

  	struct crypto_alg *alg;

  	int err = -EAGAIN;

  	if (WARN_ON_ONCE(inst == NULL))
  		return -EINVAL;

  	/* Allow the result of crypto_attr_alg_name() to be passed directly */
  	if (IS_ERR(name))
  		return PTR_ERR(name);

  	alg = crypto_find_alg(name, spawn->frontend, type, mask);
  	if (IS_ERR(alg))
  		return PTR_ERR(alg);

  
  	down_write(&crypto_alg_sem);
  	if (!crypto_is_moribund(alg)) {
  		list_add(&spawn->list, &alg->cra_users);
  		spawn->alg = alg;

  		spawn->mask = mask;
  		spawn->next = inst->spawns;
  		inst->spawns = spawn;

  		inst->alg.cra_flags |=
  			(alg->cra_flags & CRYPTO_ALG_INHERITED_FLAGS);

  		err = 0;
  	}
  	up_write(&crypto_alg_sem);

  	if (err)
  		crypto_mod_put(alg);

  	return err;
  }
  EXPORT_SYMBOL_GPL(crypto_grab_spawn);

  void crypto_drop_spawn(struct crypto_spawn *spawn)
  {

  	if (!spawn->alg) /* not yet initialized? */
  		return;

  	down_write(&crypto_alg_sem);

  	if (!spawn->dead)

  		list_del(&spawn->list);

  	up_write(&crypto_alg_sem);

  	if (!spawn->registered)

  		crypto_mod_put(spawn->alg);

  }
  EXPORT_SYMBOL_GPL(crypto_drop_spawn);

  static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)

  {

  	struct crypto_alg *alg = ERR_PTR(-EAGAIN);
  	struct crypto_alg *target;
  	bool shoot = false;

  
  	down_read(&crypto_alg_sem);

  	if (!spawn->dead) {
  		alg = spawn->alg;
  		if (!crypto_mod_get(alg)) {
  			target = crypto_alg_get(alg);
  			shoot = true;
  			alg = ERR_PTR(-EAGAIN);
  		}

  	}

  	up_read(&crypto_alg_sem);

  	if (shoot) {
  		crypto_shoot_alg(target);
  		crypto_alg_put(target);
  	}
  
  	return alg;

  }
  
  struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
  				    u32 mask)
  {
  	struct crypto_alg *alg;
  	struct crypto_tfm *tfm;
  
  	alg = crypto_spawn_alg(spawn);
  	if (IS_ERR(alg))
  		return ERR_CAST(alg);

  	tfm = ERR_PTR(-EINVAL);
  	if (unlikely((alg->cra_flags ^ type) & mask))
  		goto out_put_alg;

  	tfm = __crypto_alloc_tfm(alg, type, mask);

  	if (IS_ERR(tfm))

  		goto out_put_alg;
  
  	return tfm;

  out_put_alg:
  	crypto_mod_put(alg);

  	return tfm;
  }
  EXPORT_SYMBOL_GPL(crypto_spawn_tfm);

  void *crypto_spawn_tfm2(struct crypto_spawn *spawn)
  {
  	struct crypto_alg *alg;
  	struct crypto_tfm *tfm;
  
  	alg = crypto_spawn_alg(spawn);
  	if (IS_ERR(alg))
  		return ERR_CAST(alg);
  
  	tfm = crypto_create_tfm(alg, spawn->frontend);
  	if (IS_ERR(tfm))
  		goto out_put_alg;
  
  	return tfm;
  
  out_put_alg:
  	crypto_mod_put(alg);
  	return tfm;
  }
  EXPORT_SYMBOL_GPL(crypto_spawn_tfm2);

  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);

  struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb)

  {

  	struct rtattr *rta = tb[0];

  	struct crypto_attr_type *algt;
  
  	if (!rta)
  		return ERR_PTR(-ENOENT);
  	if (RTA_PAYLOAD(rta) < sizeof(*algt))
  		return ERR_PTR(-EINVAL);

  	if (rta->rta_type != CRYPTOA_TYPE)
  		return ERR_PTR(-EINVAL);

  
  	algt = RTA_DATA(rta);
  
  	return algt;
  }
  EXPORT_SYMBOL_GPL(crypto_get_attr_type);

  /**
   * crypto_check_attr_type() - check algorithm type and compute inherited mask
   * @tb: the template parameters
   * @type: the algorithm type the template would be instantiated as
   * @mask_ret: (output) the mask that should be passed to crypto_grab_*()
   *	      to restrict the flags of any inner algorithms
   *
   * Validate that the algorithm type the user requested is compatible with the
   * one the template would actually be instantiated as.  E.g., if the user is
   * doing crypto_alloc_shash("cbc(aes)", ...), this would return an error because
   * the "cbc" template creates an "skcipher" algorithm, not an "shash" algorithm.
   *
   * Also compute the mask to use to restrict the flags of any inner algorithms.
   *
   * Return: 0 on success; -errno on failure
   */
  int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret)

  {
  	struct crypto_attr_type *algt;
  
  	algt = crypto_get_attr_type(tb);
  	if (IS_ERR(algt))
  		return PTR_ERR(algt);
  
  	if ((algt->type ^ type) & algt->mask)
  		return -EINVAL;

  	*mask_ret = crypto_algt_inherited_mask(algt);

  	return 0;
  }
  EXPORT_SYMBOL_GPL(crypto_check_attr_type);

  const char *crypto_attr_alg_name(struct rtattr *rta)

  {

  	struct crypto_attr_alg *alga;

  	if (!rta)
  		return ERR_PTR(-ENOENT);
  	if (RTA_PAYLOAD(rta) < sizeof(*alga))

  		return ERR_PTR(-EINVAL);

  	if (rta->rta_type != CRYPTOA_ALG)
  		return ERR_PTR(-EINVAL);

  
  	alga = RTA_DATA(rta);
  	alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0;

  	return alga->name;
  }
  EXPORT_SYMBOL_GPL(crypto_attr_alg_name);

  int crypto_attr_u32(struct rtattr *rta, u32 *num)
  {
  	struct crypto_attr_u32 *nu32;
  
  	if (!rta)
  		return -ENOENT;
  	if (RTA_PAYLOAD(rta) < sizeof(*nu32))
  		return -EINVAL;
  	if (rta->rta_type != CRYPTOA_U32)
  		return -EINVAL;
  
  	nu32 = RTA_DATA(rta);
  	*num = nu32->num;
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(crypto_attr_u32);

  int crypto_inst_setname(struct crypto_instance *inst, const char *name,
  			struct crypto_alg *alg)
  {
  	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name,
  		     alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
  		return -ENAMETOOLONG;
  
  	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
  		     name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
  		return -ENAMETOOLONG;
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(crypto_inst_setname);

  void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen)
  {
  	INIT_LIST_HEAD(&queue->list);
  	queue->backlog = &queue->list;
  	queue->qlen = 0;
  	queue->max_qlen = max_qlen;
  }
  EXPORT_SYMBOL_GPL(crypto_init_queue);
  
  int crypto_enqueue_request(struct crypto_queue *queue,
  			   struct crypto_async_request *request)
  {
  	int err = -EINPROGRESS;
  
  	if (unlikely(queue->qlen >= queue->max_qlen)) {

  		if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) {
  			err = -ENOSPC;

  			goto out;

  		}
  		err = -EBUSY;

  		if (queue->backlog == &queue->list)
  			queue->backlog = &request->list;
  	}
  
  	queue->qlen++;
  	list_add_tail(&request->list, &queue->list);
  
  out:
  	return err;
  }
  EXPORT_SYMBOL_GPL(crypto_enqueue_request);

  void crypto_enqueue_request_head(struct crypto_queue *queue,
  				 struct crypto_async_request *request)
  {
  	queue->qlen++;
  	list_add(&request->list, &queue->list);
  }
  EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);

  struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)

  {
  	struct list_head *request;
  
  	if (unlikely(!queue->qlen))
  		return NULL;
  
  	queue->qlen--;
  
  	if (queue->backlog != &queue->list)
  		queue->backlog = queue->backlog->next;
  
  	request = queue->list.next;
  	list_del(request);

  	return list_entry(request, struct crypto_async_request, list);

  }
  EXPORT_SYMBOL_GPL(crypto_dequeue_request);

  static inline void crypto_inc_byte(u8 *a, unsigned int size)
  {
  	u8 *b = (a + size);
  	u8 c;
  
  	for (; size; size--) {
  		c = *--b + 1;
  		*b = c;
  		if (c)
  			break;
  	}
  }
  
  void crypto_inc(u8 *a, unsigned int size)
  {
  	__be32 *b = (__be32 *)(a + size);
  	u32 c;

  	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||

  	    IS_ALIGNED((unsigned long)b, __alignof__(*b)))

  		for (; size >= 4; size -= 4) {
  			c = be32_to_cpu(*--b) + 1;
  			*b = cpu_to_be32(c);

  			if (likely(c))

  				return;
  		}

  
  	crypto_inc_byte(a, size);
  }
  EXPORT_SYMBOL_GPL(crypto_inc);

  void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int len)

  {

  	int relalign = 0;
  
  	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
  		int size = sizeof(unsigned long);

  		int d = (((unsigned long)dst ^ (unsigned long)src1) |
  			 ((unsigned long)dst ^ (unsigned long)src2)) &
  			(size - 1);

  
  		relalign = d ? 1 << __ffs(d) : size;
  
  		/*
  		 * If we care about alignment, process as many bytes as
  		 * needed to advance dst and src to values whose alignments
  		 * equal their relative alignment. This will allow us to
  		 * process the remainder of the input using optimal strides.
  		 */
  		while (((unsigned long)dst & (relalign - 1)) && len > 0) {

  			*dst++ = *src1++ ^ *src2++;

  			len--;
  		}
  	}

  	while (IS_ENABLED(CONFIG_64BIT) && len >= 8 && !(relalign & 7)) {

  		*(u64 *)dst = *(u64 *)src1 ^  *(u64 *)src2;

  		dst += 8;

  		src1 += 8;
  		src2 += 8;

  		len -= 8;
  	}

  	while (len >= 4 && !(relalign & 3)) {

  		*(u32 *)dst = *(u32 *)src1 ^ *(u32 *)src2;

  		dst += 4;

  		src1 += 4;
  		src2 += 4;

  		len -= 4;
  	}
  
  	while (len >= 2 && !(relalign & 1)) {

  		*(u16 *)dst = *(u16 *)src1 ^ *(u16 *)src2;

  		dst += 2;

  		src1 += 2;
  		src2 += 2;

  		len -= 2;
  	}

  	while (len--)

  		*dst++ = *src1++ ^ *src2++;

  }

  EXPORT_SYMBOL_GPL(__crypto_xor);

  unsigned int crypto_alg_extsize(struct crypto_alg *alg)
  {

  	return alg->cra_ctxsize +
  	       (alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1));

  }
  EXPORT_SYMBOL_GPL(crypto_alg_extsize);

  int crypto_type_has_alg(const char *name, const struct crypto_type *frontend,
  			u32 type, u32 mask)
  {
  	int ret = 0;
  	struct crypto_alg *alg = crypto_find_alg(name, frontend, type, mask);
  
  	if (!IS_ERR(alg)) {
  		crypto_mod_put(alg);
  		ret = 1;
  	}
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(crypto_type_has_alg);

  #ifdef CONFIG_CRYPTO_STATS

  void crypto_stats_init(struct crypto_alg *alg)
  {
  	memset(&alg->stats, 0, sizeof(alg->stats));
  }
  EXPORT_SYMBOL_GPL(crypto_stats_init);

  void crypto_stats_get(struct crypto_alg *alg)
  {
  	crypto_alg_get(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_get);

  void crypto_stats_aead_encrypt(unsigned int cryptlen, struct crypto_alg *alg,
  			       int ret)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.aead.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.aead.encrypt_cnt);
  		atomic64_add(cryptlen, &alg->stats.aead.encrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_aead_encrypt);
  
  void crypto_stats_aead_decrypt(unsigned int cryptlen, struct crypto_alg *alg,
  			       int ret)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.aead.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.aead.decrypt_cnt);
  		atomic64_add(cryptlen, &alg->stats.aead.decrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_aead_decrypt);
  
  void crypto_stats_akcipher_encrypt(unsigned int src_len, int ret,
  				   struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.akcipher.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.akcipher.encrypt_cnt);
  		atomic64_add(src_len, &alg->stats.akcipher.encrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_akcipher_encrypt);
  
  void crypto_stats_akcipher_decrypt(unsigned int src_len, int ret,
  				   struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.akcipher.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.akcipher.decrypt_cnt);
  		atomic64_add(src_len, &alg->stats.akcipher.decrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_akcipher_decrypt);
  
  void crypto_stats_akcipher_sign(int ret, struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY)

  		atomic64_inc(&alg->stats.akcipher.err_cnt);

  	else

  		atomic64_inc(&alg->stats.akcipher.sign_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_akcipher_sign);
  
  void crypto_stats_akcipher_verify(int ret, struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY)

  		atomic64_inc(&alg->stats.akcipher.err_cnt);

  	else

  		atomic64_inc(&alg->stats.akcipher.verify_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_akcipher_verify);
  
  void crypto_stats_compress(unsigned int slen, int ret, struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.compress.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.compress.compress_cnt);
  		atomic64_add(slen, &alg->stats.compress.compress_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_compress);
  
  void crypto_stats_decompress(unsigned int slen, int ret, struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.compress.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.compress.decompress_cnt);
  		atomic64_add(slen, &alg->stats.compress.decompress_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_decompress);
  
  void crypto_stats_ahash_update(unsigned int nbytes, int ret,
  			       struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY)

  		atomic64_inc(&alg->stats.hash.err_cnt);

  	else

  		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_ahash_update);
  
  void crypto_stats_ahash_final(unsigned int nbytes, int ret,
  			      struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.hash.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.hash.hash_cnt);
  		atomic64_add(nbytes, &alg->stats.hash.hash_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_ahash_final);
  
  void crypto_stats_kpp_set_secret(struct crypto_alg *alg, int ret)
  {
  	if (ret)

  		atomic64_inc(&alg->stats.kpp.err_cnt);

  	else

  		atomic64_inc(&alg->stats.kpp.setsecret_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_kpp_set_secret);
  
  void crypto_stats_kpp_generate_public_key(struct crypto_alg *alg, int ret)
  {
  	if (ret)

  		atomic64_inc(&alg->stats.kpp.err_cnt);

  	else

  		atomic64_inc(&alg->stats.kpp.generate_public_key_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_kpp_generate_public_key);
  
  void crypto_stats_kpp_compute_shared_secret(struct crypto_alg *alg, int ret)
  {
  	if (ret)

  		atomic64_inc(&alg->stats.kpp.err_cnt);

  	else

  		atomic64_inc(&alg->stats.kpp.compute_shared_secret_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_kpp_compute_shared_secret);
  
  void crypto_stats_rng_seed(struct crypto_alg *alg, int ret)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY)

  		atomic64_inc(&alg->stats.rng.err_cnt);

  	else

  		atomic64_inc(&alg->stats.rng.seed_cnt);

  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_rng_seed);
  
  void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen,
  			       int ret)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.rng.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.rng.generate_cnt);
  		atomic64_add(dlen, &alg->stats.rng.generate_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_rng_generate);
  
  void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret,
  				   struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.cipher.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.cipher.encrypt_cnt);
  		atomic64_add(cryptlen, &alg->stats.cipher.encrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_skcipher_encrypt);
  
  void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret,
  				   struct crypto_alg *alg)
  {
  	if (ret && ret != -EINPROGRESS && ret != -EBUSY) {

  		atomic64_inc(&alg->stats.cipher.err_cnt);

  	} else {

  		atomic64_inc(&alg->stats.cipher.decrypt_cnt);
  		atomic64_add(cryptlen, &alg->stats.cipher.decrypt_tlen);

  	}
  	crypto_alg_put(alg);
  }
  EXPORT_SYMBOL_GPL(crypto_stats_skcipher_decrypt);
  #endif

  static int __init crypto_algapi_init(void)
  {
  	crypto_init_proc();
  	return 0;
  }
  
  static void __exit crypto_algapi_exit(void)
  {
  	crypto_exit_proc();
  }
  
  module_init(crypto_algapi_init);
  module_exit(crypto_algapi_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Cryptographic algorithms API");