Commit 21f3ca6c authored by Eric Biggers's avatar Eric Biggers Committed by Herbert Xu
Browse files

crypto: ofb - convert to skcipher_alloc_instance_simple() 



The OFB template just wraps a single block cipher algorithm, so simplify
it by converting it to use skcipher_alloc_instance_simple().

Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 6b611d98

crypto/ofb.c

+7 −112
Original line number Diff line number Diff line
@@ -13,35 +13,11 @@ 
#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/scatterlist.h>

#include <linux/slab.h>



struct crypto_ofb_ctx {

	struct crypto_cipher *child;

};





static int crypto_ofb_setkey(struct crypto_skcipher *parent, const u8 *key,

			     unsigned int keylen)

{

	struct crypto_ofb_ctx *ctx = crypto_skcipher_ctx(parent);

	struct crypto_cipher *child = ctx->child;

	int err;



	crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);

	crypto_cipher_set_flags(child, crypto_skcipher_get_flags(parent) &

				       CRYPTO_TFM_REQ_MASK);

	err = crypto_cipher_setkey(child, key, keylen);

	crypto_skcipher_set_flags(parent, crypto_cipher_get_flags(child) &

				  CRYPTO_TFM_RES_MASK);

	return err;

}



static int crypto_ofb_crypt(struct skcipher_request *req)

{

	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);

	struct crypto_ofb_ctx *ctx = crypto_skcipher_ctx(tfm);

	struct crypto_cipher *cipher = ctx->child;

	struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);

	const unsigned int bsize = crypto_cipher_blocksize(cipher);

	struct skcipher_walk walk;

	int err;
@@ -73,75 +49,15 @@ static int crypto_ofb_crypt(struct skcipher_request *req) 
	return err;

}



static int crypto_ofb_init_tfm(struct crypto_skcipher *tfm)

{

	struct skcipher_instance *inst = skcipher_alg_instance(tfm);

	struct crypto_spawn *spawn = skcipher_instance_ctx(inst);

	struct crypto_ofb_ctx *ctx = crypto_skcipher_ctx(tfm);

	struct crypto_cipher *cipher;



	cipher = crypto_spawn_cipher(spawn);

	if (IS_ERR(cipher))

		return PTR_ERR(cipher);



	ctx->child = cipher;

	return 0;

}



static void crypto_ofb_exit_tfm(struct crypto_skcipher *tfm)

{

	struct crypto_ofb_ctx *ctx = crypto_skcipher_ctx(tfm);



	crypto_free_cipher(ctx->child);

}



static void crypto_ofb_free(struct skcipher_instance *inst)

{

	crypto_drop_skcipher(skcipher_instance_ctx(inst));

	kfree(inst);

}



static int crypto_ofb_create(struct crypto_template *tmpl, struct rtattr **tb)

{

	struct skcipher_instance *inst;

	struct crypto_attr_type *algt;

	struct crypto_spawn *spawn;

	struct crypto_alg *alg;

	u32 mask;

	int err;



	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER);

	if (err)

		return err;



	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);

	if (!inst)

		return -ENOMEM;



	algt = crypto_get_attr_type(tb);

	err = PTR_ERR(algt);

	if (IS_ERR(algt))

		goto err_free_inst;



	mask = CRYPTO_ALG_TYPE_MASK |

		crypto_requires_off(algt->type, algt->mask,

				    CRYPTO_ALG_NEED_FALLBACK);



	alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, mask);

	err = PTR_ERR(alg);

	if (IS_ERR(alg))

		goto err_free_inst;



	spawn = skcipher_instance_ctx(inst);

	err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst),

				CRYPTO_ALG_TYPE_MASK);

	crypto_mod_put(alg);

	if (err)

		goto err_free_inst;



	err = crypto_inst_setname(skcipher_crypto_instance(inst), "ofb", alg);

	if (err)

		goto err_drop_spawn;

	inst = skcipher_alloc_instance_simple(tmpl, tb, &alg);

	if (IS_ERR(inst))

		return PTR_ERR(inst);



	/* OFB mode is a stream cipher. */

	inst->alg.base.cra_blocksize = 1;
@@ -152,36 +68,15 @@ static int crypto_ofb_create(struct crypto_template *tmpl, struct rtattr **tb) 
	 */

	inst->alg.chunksize = alg->cra_blocksize;



	inst->alg.base.cra_priority = alg->cra_priority;

	inst->alg.base.cra_alignmask = alg->cra_alignmask;



	inst->alg.ivsize = alg->cra_blocksize;

	inst->alg.min_keysize = alg->cra_cipher.cia_min_keysize;

	inst->alg.max_keysize = alg->cra_cipher.cia_max_keysize;



	inst->alg.base.cra_ctxsize = sizeof(struct crypto_ofb_ctx);



	inst->alg.init = crypto_ofb_init_tfm;

	inst->alg.exit = crypto_ofb_exit_tfm;



	inst->alg.setkey = crypto_ofb_setkey;

	inst->alg.encrypt = crypto_ofb_crypt;

	inst->alg.decrypt = crypto_ofb_crypt;



	inst->free = crypto_ofb_free;



	err = skcipher_register_instance(tmpl, inst);

	if (err)

		goto err_drop_spawn;

		inst->free(inst);



out:

	crypto_mod_put(alg);

	return err;



err_drop_spawn:

	crypto_drop_spawn(spawn);

err_free_inst:

	kfree(inst);

	goto out;

}



static struct crypto_template crypto_ofb_tmpl = {
@@ -204,5 +99,5 @@ module_init(crypto_ofb_module_init); 
module_exit(crypto_ofb_module_exit);



MODULE_LICENSE("GPL");

MODULE_DESCRIPTION("OFB block cipher algorithm");

MODULE_DESCRIPTION("OFB block cipher mode of operation");

MODULE_ALIAS_CRYPTO("ofb");

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