crypto: keywrap - convert to skcipher API
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@chronox.de> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>hifive-unleashed-5.1
Eric Biggers
Herbert Xu
parent
52e9368fe6
commit
6b611d98c6
198
crypto/keywrap.c
198
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;
|
||||
}
|
||||
inst = skcipher_alloc_instance_simple(tmpl, tb, &alg);
|
||||
if (IS_ERR(inst))
|
||||
return PTR_ERR(inst);
|
||||
|
||||
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 = 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);
|
||||
err = skcipher_register_instance(tmpl, inst);
|
||||
if (err)
|
||||
goto out_free_inst;
|
||||
goto out_put_alg;
|
||||
|
||||
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:
|
||||
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,
|
||||
};
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue