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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cryptographic API
*
* ARC4 Cipher Algorithm
*
* Jon Oberheide <jon@oberheide.org>
*/
#include <crypto/algapi.h>
#include <crypto/arc4.h>
#include <crypto/internal/skcipher.h>
#include <linux/init.h>
#include <linux/module.h>
static int crypto_arc4_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
unsigned int key_len)
{
struct arc4_ctx *ctx = crypto_skcipher_ctx(tfm);
return arc4_setkey(ctx, in_key, key_len);
}
static int crypto_arc4_crypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct arc4_ctx *ctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
int err;
err = skcipher_walk_virt(&walk, req, false);
while (walk.nbytes > 0) {
arc4_crypt(ctx, walk.dst.virt.addr, walk.src.virt.addr,
walk.nbytes);
err = skcipher_walk_done(&walk, 0);
}
return err;
}
static struct skcipher_alg arc4_alg = {
/*
* For legacy reasons, this is named "ecb(arc4)", not "arc4".
* Nevertheless it's actually a stream cipher, not a block cipher.
*/
.base.cra_name = "ecb(arc4)",
.base.cra_driver_name = "ecb(arc4)-generic",
.base.cra_priority = 100,
.base.cra_blocksize = ARC4_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct arc4_ctx),
.base.cra_module = THIS_MODULE,
.min_keysize = ARC4_MIN_KEY_SIZE,
.max_keysize = ARC4_MAX_KEY_SIZE,
.setkey = crypto_arc4_setkey,
.encrypt = crypto_arc4_crypt,
.decrypt = crypto_arc4_crypt,
};
static int __init arc4_init(void)
{
return crypto_register_skcipher(&arc4_alg);
}
static void __exit arc4_exit(void)
{
crypto_unregister_skcipher(&arc4_alg);
}
subsys_initcall(arc4_init);
module_exit(arc4_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ARC4 Cipher Algorithm");
MODULE_AUTHOR("Jon Oberheide <jon@oberheide.org>");
MODULE_ALIAS_CRYPTO("ecb(arc4)");
