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/*
* Cryptographic API for algorithms (i.e., low-level API).
*
* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#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/rtnetlink.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "internal.h"
static void crypto_remove_final(struct list_head *list);
static LIST_HEAD(crypto_template_list);
void crypto_larval_error(const char *name, u32 type, u32 mask)
{
struct crypto_alg *alg;
alg = crypto_alg_lookup(name, type, mask);
if (alg) {
if (crypto_is_larval(alg)) {
struct crypto_larval *larval = (void *)alg;
complete_all(&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";
char *driver_name = alg->cra_driver_name;
int len;
if (*driver_name)
return 0;
len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME)
return -ENAMETOOLONG;
memcpy(driver_name + len, suffix, sizeof(suffix));
return 0;
}
static int crypto_check_alg(struct crypto_alg *alg)
{
if (alg->cra_alignmask & (alg->cra_alignmask + 1))
return -EINVAL;
if (alg->cra_blocksize > PAGE_SIZE / 8)
return -EINVAL;
if (alg->cra_priority < 0)
return -EINVAL;
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 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;
if (list_empty(stack))
return NULL;
spawn = list_first_entry(stack, struct crypto_spawn, list);
n = list_entry(spawn->list.next, struct crypto_spawn, list);
if (spawn->alg && &n->list != stack && !n->alg)
n->alg = (n->list.next == stack) ? alg :
&list_entry(n->list.next, struct crypto_spawn,
list)->inst->alg;
list_move(&spawn->list, secondary_spawns);
return &n->list == stack ? top : &n->inst->alg.cra_users;
}
static void crypto_remove_spawn(struct crypto_spawn *spawn,
struct list_head *list)
{
struct crypto_instance *inst = spawn->inst;
struct crypto_template *tmpl = inst->tmpl;
if (crypto_is_dead(&inst->alg))
return;
inst->alg.cra_flags |= CRYPTO_ALG_DEAD;
if (hlist_unhashed(&inst->list))
return;
if (!tmpl || !crypto_tmpl_get(tmpl))
return;
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;
BUG_ON(!list_empty(&inst->alg.cra_users));
}
static 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);
}
spawns = &top;
do {
while (!list_empty(spawns)) {
struct crypto_instance *inst;
spawn = list_first_entry(spawns, struct crypto_spawn,
list);
inst = spawn->inst;
BUG_ON(&inst->alg == alg);
list_move(&spawn->list, &stack);
if (&inst->alg == nalg)
break;
spawn->alg = NULL;
spawns = &inst->alg.cra_users;
}
} while ((spawns = crypto_more_spawns(alg, &stack, &top,
&secondary_spawns)));
list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
if (spawn->alg)
list_move(&spawn->list, &spawn->alg->cra_users);
else
crypto_remove_spawn(spawn, list);
}
}
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;
atomic_set(&alg->cra_refcnt, 1);
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;
atomic_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);
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);
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;
}
printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", 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;
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 (!crypto_mod_get(alg))
continue;
larval->adult = alg;
complete_all(&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, &list, alg);
}
complete:
complete_all(&test->completion);
unlock:
up_write(&crypto_alg_sem);
crypto_remove_final(&list);
}
EXPORT_SYMBOL_GPL(crypto_alg_tested);
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);
}
}
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_interruptible(&larval->completion);
WARN_ON(err);
out:
crypto_larval_kill(&larval->alg);
}
int crypto_register_alg(struct crypto_alg *alg)
{
struct crypto_larval *larval;
int err;
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;
crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
list_del_init(&alg->cra_list);
crypto_remove_spawns(alg, list, NULL);
return 0;
}
int 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 (ret)
return ret;
BUG_ON(atomic_read(&alg->cra_refcnt) != 1);
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)
{
struct crypto_larval *larval;
int err;
err = crypto_check_alg(&inst->alg);
if (err)
goto err;
inst->alg.cra_module = tmpl->module;
down_write(&crypto_alg_sem);
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);
int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg,
struct crypto_instance *inst, u32 mask)
{
int err = -EAGAIN;
spawn->inst = inst;
spawn->mask = mask;
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);
int crypto_init_spawn2(struct crypto_spawn *spawn, struct crypto_alg *alg,
struct crypto_instance *inst,
const struct crypto_type *frontend)
{
int err = -EINVAL;
if ((alg->cra_flags ^ frontend->type) & frontend->maskset)
goto out;
spawn->frontend = frontend;
err = crypto_init_spawn(spawn, alg, inst, frontend->maskset);
out:
return err;
}
EXPORT_SYMBOL_GPL(crypto_init_spawn2);
void crypto_drop_spawn(struct crypto_spawn *spawn)
{
if (!spawn->alg)
return;
down_write(&crypto_alg_sem);
list_del(&spawn->list);
up_write(&crypto_alg_sem);
}
EXPORT_SYMBOL_GPL(crypto_drop_spawn);
static struct crypto_alg *crypto_spawn_alg(struct crypto_spawn *spawn)
{
struct crypto_alg *alg;
struct crypto_alg *alg2;
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);
}
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);
int crypto_check_attr_type(struct rtattr **tb, u32 type)
{
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;
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);
struct crypto_alg *crypto_attr_alg2(struct rtattr *rta,
const struct crypto_type *frontend,
u32 type, u32 mask)
{
const char *name;
int err;
name = crypto_attr_alg_name(rta);
err = PTR_ERR(name);
if (IS_ERR(name))
return ERR_PTR(err);
return crypto_find_alg(name, frontend, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_attr_alg2);
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);
void *crypto_alloc_instance2(const char *name, struct crypto_alg *alg,
unsigned int head)
{
struct crypto_instance *inst;
char *p;
int err;
p = kzalloc(head + sizeof(*inst) + sizeof(struct crypto_spawn),
GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
inst = (void *)(p + head);
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;
return p;
err_free_inst:
kfree(p);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_alloc_instance2);
struct crypto_instance *crypto_alloc_instance(const char *name,
struct crypto_alg *alg)
{
struct crypto_instance *inst;
struct crypto_spawn *spawn;
int err;
inst = crypto_alloc_instance2(name, alg, 0);
if (IS_ERR(inst))
goto out;
spawn = crypto_instance_ctx(inst);
err = crypto_init_spawn(spawn, alg, inst,
CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
if (err)
goto err_free_inst;
return inst;
err_free_inst:
kfree(inst);
inst = ERR_PTR(err);
out:
return inst;
}
EXPORT_SYMBOL_GPL(crypto_alloc_instance);
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)) {
err = -EBUSY;
if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG))
goto out;
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_dequeue_request(struct crypto_queue *queue, unsigned int offset)
{
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 (char *)list_entry(request, struct crypto_async_request, list) -
offset;
}
EXPORT_SYMBOL_GPL(__crypto_dequeue_request);
struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
{
return __crypto_dequeue_request(queue, 0);
}
EXPORT_SYMBOL_GPL(crypto_dequeue_request);
int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm)
{
struct crypto_async_request *req;
list_for_each_entry(req, &queue->list, list) {
if (req->tfm == tfm)
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(crypto_tfm_in_queue);
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;
for (; size >= 4; size -= 4) {
c = be32_to_cpu(*--b) + 1;
*b = cpu_to_be32(c);
if (c)
return;
}
crypto_inc_byte(a, size);
}
EXPORT_SYMBOL_GPL(crypto_inc);
static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size)
{
for (; size; size--)
*a++ ^= *b++;
}
void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
{
u32 *a = (u32 *)dst;
u32 *b = (u32 *)src;
for (; size >= 4; size -= 4)
*a++ ^= *b++;
crypto_xor_byte((u8 *)a, (u8 *)b, size);
}
EXPORT_SYMBOL_GPL(crypto_xor);
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");
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