From: Eric Biggers <ebiggers@xxxxxxxxxx>
The CFB template just wraps a single block cipher algorithm, so simplify
it by converting it to use skcipher_alloc_instance_simple().
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/cfb.c | 127 ++++-----------------------------------------------
1 file changed, 9 insertions(+), 118 deletions(-)
diff --git a/crypto/cfb.c b/crypto/cfb.c
index 4abfe32ff8451..03ac847f6d6ab 100644
--- a/crypto/cfb.c
+++ b/crypto/cfb.c
@@ -25,28 +25,17 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/slab.h>
#include <linux/string.h>
-#include <linux/types.h>
-
-struct crypto_cfb_ctx {
- struct crypto_cipher *child;
-};
static unsigned int crypto_cfb_bsize(struct crypto_skcipher *tfm)
{
- struct crypto_cfb_ctx *ctx = crypto_skcipher_ctx(tfm);
- struct crypto_cipher *child = ctx->child;
-
- return crypto_cipher_blocksize(child);
+ return crypto_cipher_blocksize(skcipher_cipher_simple(tfm));
}
static void crypto_cfb_encrypt_one(struct crypto_skcipher *tfm,
const u8 *src, u8 *dst)
{
- struct crypto_cfb_ctx *ctx = crypto_skcipher_ctx(tfm);
-
- crypto_cipher_encrypt_one(ctx->child, dst, src);
+ crypto_cipher_encrypt_one(skcipher_cipher_simple(tfm), dst, src);
}
/* final encrypt and decrypt is the same */
@@ -186,22 +175,6 @@ static int crypto_cfb_decrypt_blocks(struct skcipher_walk *walk,
return crypto_cfb_decrypt_segment(walk, tfm);
}
-static int crypto_cfb_setkey(struct crypto_skcipher *parent, const u8 *key,
- unsigned int keylen)
-{
- struct crypto_cfb_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_cfb_decrypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
@@ -224,79 +197,18 @@ static int crypto_cfb_decrypt(struct skcipher_request *req)
return err;
}
-static int crypto_cfb_init_tfm(struct crypto_skcipher *tfm)
-{
- struct skcipher_instance *inst = skcipher_alg_instance(tfm);
- struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
- struct crypto_cfb_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_cfb_exit_tfm(struct crypto_skcipher *tfm)
-{
- struct crypto_cfb_ctx *ctx = crypto_skcipher_ctx(tfm);
-
- crypto_free_cipher(ctx->child);
-}
-
-static void crypto_cfb_free(struct skcipher_instance *inst)
-{
- crypto_drop_skcipher(skcipher_instance_ctx(inst));
- kfree(inst);
-}
-
static int crypto_cfb_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;
+ inst = skcipher_alloc_instance_simple(tmpl, tb, &alg);
+ if (IS_ERR(inst))
+ return PTR_ERR(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);
- if (err)
- goto err_put_alg;
-
- err = crypto_inst_setname(skcipher_crypto_instance(inst), "cfb", alg);
- if (err)
- goto err_drop_spawn;
-
- inst->alg.base.cra_priority = alg->cra_priority;
- /* we're a stream cipher independend of the crypto cra_blocksize */
+ /* CFB mode is a stream cipher. */
inst->alg.base.cra_blocksize = 1;
- inst->alg.base.cra_alignmask = alg->cra_alignmask;
/*
* To simplify the implementation, configure the skcipher walk to only
@@ -304,36 +216,15 @@ static int crypto_cfb_create(struct crypto_template *tmpl, struct rtattr **tb)
*/
inst->alg.chunksize = alg->cra_blocksize;
- 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_cfb_ctx);
-
- inst->alg.init = crypto_cfb_init_tfm;
- inst->alg.exit = crypto_cfb_exit_tfm;
-
- inst->alg.setkey = crypto_cfb_setkey;
inst->alg.encrypt = crypto_cfb_encrypt;
inst->alg.decrypt = crypto_cfb_decrypt;
- inst->free = crypto_cfb_free;
-
err = skcipher_register_instance(tmpl, inst);
if (err)
- goto err_drop_spawn;
- crypto_mod_put(alg);
-
-out:
- return err;
+ inst->free(inst);
-err_drop_spawn:
- crypto_drop_spawn(spawn);
-err_put_alg:
crypto_mod_put(alg);
-err_free_inst:
- kfree(inst);
- goto out;
+ return err;
}
static struct crypto_template crypto_cfb_tmpl = {
@@ -356,5 +247,5 @@ module_init(crypto_cfb_module_init);
module_exit(crypto_cfb_module_exit);
MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("CFB block cipher algorithm");
+MODULE_DESCRIPTION("CFB block cipher mode of operation");
MODULE_ALIAS_CRYPTO("cfb");
--
2.20.1
