You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
325 lines
6.3 KiB
325 lines
6.3 KiB
/*
|
|
* Scatterlist Cryptographic API.
|
|
*
|
|
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
|
|
* Copyright (c) 2002 David S. Miller (davem@redhat.com)
|
|
* Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
|
|
*
|
|
* Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
|
|
* and Nettle, by Niels Möller.
|
|
*
|
|
* 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/compiler.h>
|
|
#include <linux/init.h>
|
|
#include <linux/crypto.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/kmod.h>
|
|
#include <linux/rwsem.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
#include "internal.h"
|
|
|
|
LIST_HEAD(crypto_alg_list);
|
|
DECLARE_RWSEM(crypto_alg_sem);
|
|
|
|
static inline int crypto_alg_get(struct crypto_alg *alg)
|
|
{
|
|
return try_module_get(alg->cra_module);
|
|
}
|
|
|
|
static inline void crypto_alg_put(struct crypto_alg *alg)
|
|
{
|
|
module_put(alg->cra_module);
|
|
}
|
|
|
|
static struct crypto_alg *crypto_alg_lookup(const char *name)
|
|
{
|
|
struct crypto_alg *q, *alg = NULL;
|
|
int best = -1;
|
|
|
|
if (!name)
|
|
return NULL;
|
|
|
|
down_read(&crypto_alg_sem);
|
|
|
|
list_for_each_entry(q, &crypto_alg_list, cra_list) {
|
|
int exact, fuzzy;
|
|
|
|
exact = !strcmp(q->cra_driver_name, name);
|
|
fuzzy = !strcmp(q->cra_name, name);
|
|
if (!exact && !(fuzzy && q->cra_priority > best))
|
|
continue;
|
|
|
|
if (unlikely(!crypto_alg_get(q)))
|
|
continue;
|
|
|
|
best = q->cra_priority;
|
|
if (alg)
|
|
crypto_alg_put(alg);
|
|
alg = q;
|
|
|
|
if (exact)
|
|
break;
|
|
}
|
|
|
|
up_read(&crypto_alg_sem);
|
|
return alg;
|
|
}
|
|
|
|
/* A far more intelligent version of this is planned. For now, just
|
|
* try an exact match on the name of the algorithm. */
|
|
static inline struct crypto_alg *crypto_alg_mod_lookup(const char *name)
|
|
{
|
|
return try_then_request_module(crypto_alg_lookup(name), name);
|
|
}
|
|
|
|
static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
|
|
{
|
|
tfm->crt_flags = flags & CRYPTO_TFM_REQ_MASK;
|
|
flags &= ~CRYPTO_TFM_REQ_MASK;
|
|
|
|
switch (crypto_tfm_alg_type(tfm)) {
|
|
case CRYPTO_ALG_TYPE_CIPHER:
|
|
return crypto_init_cipher_flags(tfm, flags);
|
|
|
|
case CRYPTO_ALG_TYPE_DIGEST:
|
|
return crypto_init_digest_flags(tfm, flags);
|
|
|
|
case CRYPTO_ALG_TYPE_COMPRESS:
|
|
return crypto_init_compress_flags(tfm, flags);
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
BUG();
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int crypto_init_ops(struct crypto_tfm *tfm)
|
|
{
|
|
switch (crypto_tfm_alg_type(tfm)) {
|
|
case CRYPTO_ALG_TYPE_CIPHER:
|
|
return crypto_init_cipher_ops(tfm);
|
|
|
|
case CRYPTO_ALG_TYPE_DIGEST:
|
|
return crypto_init_digest_ops(tfm);
|
|
|
|
case CRYPTO_ALG_TYPE_COMPRESS:
|
|
return crypto_init_compress_ops(tfm);
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
BUG();
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void crypto_exit_ops(struct crypto_tfm *tfm)
|
|
{
|
|
switch (crypto_tfm_alg_type(tfm)) {
|
|
case CRYPTO_ALG_TYPE_CIPHER:
|
|
crypto_exit_cipher_ops(tfm);
|
|
break;
|
|
|
|
case CRYPTO_ALG_TYPE_DIGEST:
|
|
crypto_exit_digest_ops(tfm);
|
|
break;
|
|
|
|
case CRYPTO_ALG_TYPE_COMPRESS:
|
|
crypto_exit_compress_ops(tfm);
|
|
break;
|
|
|
|
default:
|
|
BUG();
|
|
|
|
}
|
|
}
|
|
|
|
static unsigned int crypto_ctxsize(struct crypto_alg *alg, int flags)
|
|
{
|
|
unsigned int len;
|
|
|
|
switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
|
|
default:
|
|
BUG();
|
|
|
|
case CRYPTO_ALG_TYPE_CIPHER:
|
|
len = crypto_cipher_ctxsize(alg, flags);
|
|
break;
|
|
|
|
case CRYPTO_ALG_TYPE_DIGEST:
|
|
len = crypto_digest_ctxsize(alg, flags);
|
|
break;
|
|
|
|
case CRYPTO_ALG_TYPE_COMPRESS:
|
|
len = crypto_compress_ctxsize(alg, flags);
|
|
break;
|
|
}
|
|
|
|
return len + alg->cra_alignmask;
|
|
}
|
|
|
|
struct crypto_tfm *crypto_alloc_tfm(const char *name, u32 flags)
|
|
{
|
|
struct crypto_tfm *tfm = NULL;
|
|
struct crypto_alg *alg;
|
|
unsigned int tfm_size;
|
|
|
|
alg = crypto_alg_mod_lookup(name);
|
|
if (alg == NULL)
|
|
goto out;
|
|
|
|
tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, flags);
|
|
tfm = kmalloc(tfm_size, GFP_KERNEL);
|
|
if (tfm == NULL)
|
|
goto out_put;
|
|
|
|
memset(tfm, 0, tfm_size);
|
|
|
|
tfm->__crt_alg = alg;
|
|
|
|
if (crypto_init_flags(tfm, flags))
|
|
goto out_free_tfm;
|
|
|
|
if (crypto_init_ops(tfm)) {
|
|
crypto_exit_ops(tfm);
|
|
goto out_free_tfm;
|
|
}
|
|
|
|
goto out;
|
|
|
|
out_free_tfm:
|
|
kfree(tfm);
|
|
tfm = NULL;
|
|
out_put:
|
|
crypto_alg_put(alg);
|
|
out:
|
|
return tfm;
|
|
}
|
|
|
|
void crypto_free_tfm(struct crypto_tfm *tfm)
|
|
{
|
|
struct crypto_alg *alg;
|
|
int size;
|
|
|
|
if (unlikely(!tfm))
|
|
return;
|
|
|
|
alg = tfm->__crt_alg;
|
|
size = sizeof(*tfm) + alg->cra_ctxsize;
|
|
|
|
crypto_exit_ops(tfm);
|
|
crypto_alg_put(alg);
|
|
memset(tfm, 0, size);
|
|
kfree(tfm);
|
|
}
|
|
|
|
static inline int crypto_set_driver_name(struct crypto_alg *alg)
|
|
{
|
|
static const char suffix[] = "-generic";
|
|
char *driver_name = (char *)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;
|
|
}
|
|
|
|
int crypto_register_alg(struct crypto_alg *alg)
|
|
{
|
|
int ret;
|
|
struct crypto_alg *q;
|
|
|
|
if (alg->cra_alignmask & (alg->cra_alignmask + 1))
|
|
return -EINVAL;
|
|
|
|
if (alg->cra_alignmask & alg->cra_blocksize)
|
|
return -EINVAL;
|
|
|
|
if (alg->cra_blocksize > PAGE_SIZE / 8)
|
|
return -EINVAL;
|
|
|
|
if (alg->cra_priority < 0)
|
|
return -EINVAL;
|
|
|
|
ret = crypto_set_driver_name(alg);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
|
|
down_write(&crypto_alg_sem);
|
|
|
|
list_for_each_entry(q, &crypto_alg_list, cra_list) {
|
|
if (!strcmp(q->cra_driver_name, alg->cra_driver_name)) {
|
|
ret = -EEXIST;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
list_add_tail(&alg->cra_list, &crypto_alg_list);
|
|
out:
|
|
up_write(&crypto_alg_sem);
|
|
return ret;
|
|
}
|
|
|
|
int crypto_unregister_alg(struct crypto_alg *alg)
|
|
{
|
|
int ret = -ENOENT;
|
|
struct crypto_alg *q;
|
|
|
|
BUG_ON(!alg->cra_module);
|
|
|
|
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:
|
|
up_write(&crypto_alg_sem);
|
|
return ret;
|
|
}
|
|
|
|
int crypto_alg_available(const char *name, u32 flags)
|
|
{
|
|
int ret = 0;
|
|
struct crypto_alg *alg = crypto_alg_mod_lookup(name);
|
|
|
|
if (alg) {
|
|
crypto_alg_put(alg);
|
|
ret = 1;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int __init init_crypto(void)
|
|
{
|
|
printk(KERN_INFO "Initializing Cryptographic API\n");
|
|
crypto_init_proc();
|
|
return 0;
|
|
}
|
|
|
|
__initcall(init_crypto);
|
|
|
|
EXPORT_SYMBOL_GPL(crypto_register_alg);
|
|
EXPORT_SYMBOL_GPL(crypto_unregister_alg);
|
|
EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
|
|
EXPORT_SYMBOL_GPL(crypto_free_tfm);
|
|
EXPORT_SYMBOL_GPL(crypto_alg_available);
|
|
|