From: Eric Biggers <ebiggers@xxxxxxxxxx>
Convert the keywrap template from the deprecated "blkcipher" API to the
"skcipher" API, taking advantage of skcipher_alloc_instance_simple() to
simplify it considerably.
Cc: Stephan Mueller <smueller@xxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/keywrap.c | 198 ++++++++++++++++-------------------------------
1 file changed, 65 insertions(+), 133 deletions(-)
diff --git a/crypto/keywrap.c b/crypto/keywrap.c
index ec5c6a087c901..a5cfe610d8f40 100644
--- a/crypto/keywrap.c
+++ b/crypto/keywrap.c
@@ -56,7 +56,7 @@
* u8 *iv = data;
* u8 *pt = data + crypto_skcipher_ivsize(tfm);
* <ensure that pt contains the plaintext of size ptlen>
- * sg_init_one(&sg, ptdata, ptlen);
+ * sg_init_one(&sg, pt, ptlen);
* skcipher_request_set_crypt(req, &sg, &sg, ptlen, iv);
*
* ==> After encryption, data now contains full KW result as per SP800-38F.
@@ -70,8 +70,8 @@
* u8 *iv = data;
* u8 *ct = data + crypto_skcipher_ivsize(tfm);
* unsigned int ctlen = datalen - crypto_skcipher_ivsize(tfm);
- * sg_init_one(&sg, ctdata, ctlen);
- * skcipher_request_set_crypt(req, &sg, &sg, ptlen, iv);
+ * sg_init_one(&sg, ct, ctlen);
+ * skcipher_request_set_crypt(req, &sg, &sg, ctlen, iv);
*
* ==> After decryption (which hopefully does not return EBADMSG), the ct
* pointer now points to the plaintext of size ctlen.
@@ -87,10 +87,6 @@
#include <crypto/scatterwalk.h>
#include <crypto/internal/skcipher.h>
-struct crypto_kw_ctx {
- struct crypto_cipher *child;
-};
-
struct crypto_kw_block {
#define SEMIBSIZE 8
__be64 A;
@@ -124,16 +120,13 @@ static void crypto_kw_scatterlist_ff(struct scatter_walk *walk,
}
}
-static int crypto_kw_decrypt(struct blkcipher_desc *desc,
- struct scatterlist *dst, struct scatterlist *src,
- unsigned int nbytes)
+static int crypto_kw_decrypt(struct skcipher_request *req)
{
- struct crypto_blkcipher *tfm = desc->tfm;
- struct crypto_kw_ctx *ctx = crypto_blkcipher_ctx(tfm);
- struct crypto_cipher *child = ctx->child;
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
struct crypto_kw_block block;
- struct scatterlist *lsrc, *ldst;
- u64 t = 6 * ((nbytes) >> 3);
+ struct scatterlist *src, *dst;
+ u64 t = 6 * ((req->cryptlen) >> 3);
unsigned int i;
int ret = 0;
@@ -141,27 +134,27 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc,
* Require at least 2 semiblocks (note, the 3rd semiblock that is
* required by SP800-38F is the IV.
*/
- if (nbytes < (2 * SEMIBSIZE) || nbytes % SEMIBSIZE)
+ if (req->cryptlen < (2 * SEMIBSIZE) || req->cryptlen % SEMIBSIZE)
return -EINVAL;
/* Place the IV into block A */
- memcpy(&block.A, desc->info, SEMIBSIZE);
+ memcpy(&block.A, req->iv, SEMIBSIZE);
/*
* src scatterlist is read-only. dst scatterlist is r/w. During the
- * first loop, lsrc points to src and ldst to dst. For any
- * subsequent round, the code operates on dst only.
+ * first loop, src points to req->src and dst to req->dst. For any
+ * subsequent round, the code operates on req->dst only.
*/
- lsrc = src;
- ldst = dst;
+ src = req->src;
+ dst = req->dst;
for (i = 0; i < 6; i++) {
struct scatter_walk src_walk, dst_walk;
- unsigned int tmp_nbytes = nbytes;
+ unsigned int nbytes = req->cryptlen;
- while (tmp_nbytes) {
- /* move pointer by tmp_nbytes in the SGL */
- crypto_kw_scatterlist_ff(&src_walk, lsrc, tmp_nbytes);
+ while (nbytes) {
+ /* move pointer by nbytes in the SGL */
+ crypto_kw_scatterlist_ff(&src_walk, src, nbytes);
/* get the source block */
scatterwalk_copychunks(&block.R, &src_walk, SEMIBSIZE,
false);
@@ -170,21 +163,21 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc,
block.A ^= cpu_to_be64(t);
t--;
/* perform KW operation: decrypt block */
- crypto_cipher_decrypt_one(child, (u8*)&block,
- (u8*)&block);
+ crypto_cipher_decrypt_one(cipher, (u8 *)&block,
+ (u8 *)&block);
- /* move pointer by tmp_nbytes in the SGL */
- crypto_kw_scatterlist_ff(&dst_walk, ldst, tmp_nbytes);
+ /* move pointer by nbytes in the SGL */
+ crypto_kw_scatterlist_ff(&dst_walk, dst, nbytes);
/* Copy block->R into place */
scatterwalk_copychunks(&block.R, &dst_walk, SEMIBSIZE,
true);
- tmp_nbytes -= SEMIBSIZE;
+ nbytes -= SEMIBSIZE;
}
/* we now start to operate on the dst SGL only */
- lsrc = dst;
- ldst = dst;
+ src = req->dst;
+ dst = req->dst;
}
/* Perform authentication check */
@@ -196,15 +189,12 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc,
return ret;
}
-static int crypto_kw_encrypt(struct blkcipher_desc *desc,
- struct scatterlist *dst, struct scatterlist *src,
- unsigned int nbytes)
+static int crypto_kw_encrypt(struct skcipher_request *req)
{
- struct crypto_blkcipher *tfm = desc->tfm;
- struct crypto_kw_ctx *ctx = crypto_blkcipher_ctx(tfm);
- struct crypto_cipher *child = ctx->child;
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
struct crypto_kw_block block;
- struct scatterlist *lsrc, *ldst;
+ struct scatterlist *src, *dst;
u64 t = 1;
unsigned int i;
@@ -214,7 +204,7 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc,
* This means that the dst memory must be one semiblock larger than src.
* Also ensure that the given data is aligned to semiblock.
*/
- if (nbytes < (2 * SEMIBSIZE) || nbytes % SEMIBSIZE)
+ if (req->cryptlen < (2 * SEMIBSIZE) || req->cryptlen % SEMIBSIZE)
return -EINVAL;
/*
@@ -225,26 +215,26 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc,
/*
* src scatterlist is read-only. dst scatterlist is r/w. During the
- * first loop, lsrc points to src and ldst to dst. For any
- * subsequent round, the code operates on dst only.
+ * first loop, src points to req->src and dst to req->dst. For any
+ * subsequent round, the code operates on req->dst only.
*/
- lsrc = src;
- ldst = dst;
+ src = req->src;
+ dst = req->dst;
for (i = 0; i < 6; i++) {
struct scatter_walk src_walk, dst_walk;
- unsigned int tmp_nbytes = nbytes;
+ unsigned int nbytes = req->cryptlen;
- scatterwalk_start(&src_walk, lsrc);
- scatterwalk_start(&dst_walk, ldst);
+ scatterwalk_start(&src_walk, src);
+ scatterwalk_start(&dst_walk, dst);
- while (tmp_nbytes) {
+ while (nbytes) {
/* get the source block */
scatterwalk_copychunks(&block.R, &src_walk, SEMIBSIZE,
false);
/* perform KW operation: encrypt block */
- crypto_cipher_encrypt_one(child, (u8 *)&block,
+ crypto_cipher_encrypt_one(cipher, (u8 *)&block,
(u8 *)&block);
/* perform KW operation: modify IV with counter */
block.A ^= cpu_to_be64(t);
@@ -254,117 +244,59 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc,
scatterwalk_copychunks(&block.R, &dst_walk, SEMIBSIZE,
true);
- tmp_nbytes -= SEMIBSIZE;
+ nbytes -= SEMIBSIZE;
}
/* we now start to operate on the dst SGL only */
- lsrc = dst;
- ldst = dst;
+ src = req->dst;
+ dst = req->dst;
}
/* establish the IV for the caller to pick up */
- memcpy(desc->info, &block.A, SEMIBSIZE);
+ memcpy(req->iv, &block.A, SEMIBSIZE);
memzero_explicit(&block, sizeof(struct crypto_kw_block));
return 0;
}
-static int crypto_kw_setkey(struct crypto_tfm *parent, const u8 *key,
- unsigned int keylen)
+static int crypto_kw_create(struct crypto_template *tmpl, struct rtattr **tb)
{
- struct crypto_kw_ctx *ctx = crypto_tfm_ctx(parent);
- struct crypto_cipher *child = ctx->child;
+ struct skcipher_instance *inst;
+ struct crypto_alg *alg;
int err;
- crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
- crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
- CRYPTO_TFM_REQ_MASK);
- err = crypto_cipher_setkey(child, key, keylen);
- crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
- CRYPTO_TFM_RES_MASK);
- return err;
-}
-
-static int crypto_kw_init_tfm(struct crypto_tfm *tfm)
-{
- struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
- struct crypto_spawn *spawn = crypto_instance_ctx(inst);
- struct crypto_kw_ctx *ctx = crypto_tfm_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_kw_exit_tfm(struct crypto_tfm *tfm)
-{
- struct crypto_kw_ctx *ctx = crypto_tfm_ctx(tfm);
-
- crypto_free_cipher(ctx->child);
-}
-
-static struct crypto_instance *crypto_kw_alloc(struct rtattr **tb)
-{
- struct crypto_instance *inst = NULL;
- struct crypto_alg *alg = NULL;
- int err;
-
- err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
- if (err)
- return ERR_PTR(err);
-
- alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
- CRYPTO_ALG_TYPE_MASK);
- if (IS_ERR(alg))
- return ERR_CAST(alg);
+ inst = skcipher_alloc_instance_simple(tmpl, tb, &alg);
+ if (IS_ERR(inst))
+ return PTR_ERR(inst);
- inst = ERR_PTR(-EINVAL);
+ err = -EINVAL;
/* Section 5.1 requirement for KW */
if (alg->cra_blocksize != sizeof(struct crypto_kw_block))
- goto err;
+ goto out_free_inst;
- inst = crypto_alloc_instance("kw", alg);
- if (IS_ERR(inst))
- goto err;
+ inst->alg.base.cra_blocksize = SEMIBSIZE;
+ inst->alg.base.cra_alignmask = 0;
+ inst->alg.ivsize = SEMIBSIZE;
- inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
- inst->alg.cra_priority = alg->cra_priority;
- inst->alg.cra_blocksize = SEMIBSIZE;
- inst->alg.cra_alignmask = 0;
- inst->alg.cra_type = &crypto_blkcipher_type;
- inst->alg.cra_blkcipher.ivsize = SEMIBSIZE;
- inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
- inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
+ inst->alg.encrypt = crypto_kw_encrypt;
+ inst->alg.decrypt = crypto_kw_decrypt;
- inst->alg.cra_ctxsize = sizeof(struct crypto_kw_ctx);
-
- inst->alg.cra_init = crypto_kw_init_tfm;
- inst->alg.cra_exit = crypto_kw_exit_tfm;
-
- inst->alg.cra_blkcipher.setkey = crypto_kw_setkey;
- inst->alg.cra_blkcipher.encrypt = crypto_kw_encrypt;
- inst->alg.cra_blkcipher.decrypt = crypto_kw_decrypt;
+ err = skcipher_register_instance(tmpl, inst);
+ if (err)
+ goto out_free_inst;
+ goto out_put_alg;
-err:
+out_free_inst:
+ inst->free(inst);
+out_put_alg:
crypto_mod_put(alg);
- return inst;
-}
-
-static void crypto_kw_free(struct crypto_instance *inst)
-{
- crypto_drop_spawn(crypto_instance_ctx(inst));
- kfree(inst);
+ return err;
}
static struct crypto_template crypto_kw_tmpl = {
.name = "kw",
- .alloc = crypto_kw_alloc,
- .free = crypto_kw_free,
+ .create = crypto_kw_create,
.module = THIS_MODULE,
};
--
2.20.1
