[PATCH 4/26] dm crypt: Use skcipher and ahash

From: Herbert Xu
Date: Sun Jan 24 2016 - 08:29:14 EST


This patch replaces uses of ablkcipher with skcipher, and the long
obsolete hash interface with ahash.

Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
---

drivers/md/dm-crypt.c | 93 +++++++++++++++++++++++++-------------------------
1 file changed, 48 insertions(+), 45 deletions(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 3147c8d..06a4e3c 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -28,6 +28,7 @@
#include <crypto/hash.h>
#include <crypto/md5.h>
#include <crypto/algapi.h>
+#include <crypto/skcipher.h>

#include <linux/device-mapper.h>

@@ -44,7 +45,7 @@ struct convert_context {
struct bvec_iter iter_out;
sector_t cc_sector;
atomic_t cc_pending;
- struct ablkcipher_request *req;
+ struct skcipher_request *req;
};

/*
@@ -86,7 +87,7 @@ struct crypt_iv_operations {
};

struct iv_essiv_private {
- struct crypto_hash *hash_tfm;
+ struct crypto_ahash *hash_tfm;
u8 *salt;
};

@@ -153,13 +154,13 @@ struct crypt_config {

/* ESSIV: struct crypto_cipher *essiv_tfm */
void *iv_private;
- struct crypto_ablkcipher **tfms;
+ struct crypto_skcipher **tfms;
unsigned tfms_count;

/*
* Layout of each crypto request:
*
- * struct ablkcipher_request
+ * struct skcipher_request
* context
* padding
* struct dm_crypt_request
@@ -189,7 +190,7 @@ static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
/*
* Use this to access cipher attributes that are the same for each CPU.
*/
-static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
+static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
{
return cc->tfms[0];
}
@@ -263,23 +264,25 @@ static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
static int crypt_iv_essiv_init(struct crypt_config *cc)
{
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
- struct hash_desc desc;
+ AHASH_REQUEST_ON_STACK(req, essiv->hash_tfm);
struct scatterlist sg;
struct crypto_cipher *essiv_tfm;
int err;

sg_init_one(&sg, cc->key, cc->key_size);
- desc.tfm = essiv->hash_tfm;
- desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ ahash_request_set_tfm(req, essiv->hash_tfm);
+ ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+ ahash_request_set_crypt(req, &sg, essiv->salt, cc->key_size);

- err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt);
+ err = crypto_ahash_digest(req);
+ ahash_request_zero(req);
if (err)
return err;

essiv_tfm = cc->iv_private;

err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
- crypto_hash_digestsize(essiv->hash_tfm));
+ crypto_ahash_digestsize(essiv->hash_tfm));
if (err)
return err;

@@ -290,7 +293,7 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
static int crypt_iv_essiv_wipe(struct crypt_config *cc)
{
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
- unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
+ unsigned salt_size = crypto_ahash_digestsize(essiv->hash_tfm);
struct crypto_cipher *essiv_tfm;
int r, err = 0;

@@ -320,7 +323,7 @@ static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
}

if (crypto_cipher_blocksize(essiv_tfm) !=
- crypto_ablkcipher_ivsize(any_tfm(cc))) {
+ crypto_skcipher_ivsize(any_tfm(cc))) {
ti->error = "Block size of ESSIV cipher does "
"not match IV size of block cipher";
crypto_free_cipher(essiv_tfm);
@@ -342,7 +345,7 @@ static void crypt_iv_essiv_dtr(struct crypt_config *cc)
struct crypto_cipher *essiv_tfm;
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;

- crypto_free_hash(essiv->hash_tfm);
+ crypto_free_ahash(essiv->hash_tfm);
essiv->hash_tfm = NULL;

kzfree(essiv->salt);
@@ -360,7 +363,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
struct crypto_cipher *essiv_tfm = NULL;
- struct crypto_hash *hash_tfm = NULL;
+ struct crypto_ahash *hash_tfm = NULL;
u8 *salt = NULL;
int err;

@@ -370,14 +373,14 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
}

/* Allocate hash algorithm */
- hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC);
+ hash_tfm = crypto_alloc_ahash(opts, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(hash_tfm)) {
ti->error = "Error initializing ESSIV hash";
err = PTR_ERR(hash_tfm);
goto bad;
}

- salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL);
+ salt = kzalloc(crypto_ahash_digestsize(hash_tfm), GFP_KERNEL);
if (!salt) {
ti->error = "Error kmallocing salt storage in ESSIV";
err = -ENOMEM;
@@ -388,7 +391,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
cc->iv_gen_private.essiv.hash_tfm = hash_tfm;

essiv_tfm = setup_essiv_cpu(cc, ti, salt,
- crypto_hash_digestsize(hash_tfm));
+ crypto_ahash_digestsize(hash_tfm));
if (IS_ERR(essiv_tfm)) {
crypt_iv_essiv_dtr(cc);
return PTR_ERR(essiv_tfm);
@@ -399,7 +402,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,

bad:
if (hash_tfm && !IS_ERR(hash_tfm))
- crypto_free_hash(hash_tfm);
+ crypto_free_ahash(hash_tfm);
kfree(salt);
return err;
}
@@ -419,7 +422,7 @@ static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
- unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
+ unsigned bs = crypto_skcipher_blocksize(any_tfm(cc));
int log = ilog2(bs);

/* we need to calculate how far we must shift the sector count
@@ -816,27 +819,27 @@ static void crypt_convert_init(struct crypt_config *cc,
}

static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
- struct ablkcipher_request *req)
+ struct skcipher_request *req)
{
return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
}

-static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
+static struct skcipher_request *req_of_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
- return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
+ return (struct skcipher_request *)((char *)dmreq - cc->dmreq_start);
}

static u8 *iv_of_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
return (u8 *)ALIGN((unsigned long)(dmreq + 1),
- crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
+ crypto_skcipher_alignmask(any_tfm(cc)) + 1);
}

static int crypt_convert_block(struct crypt_config *cc,
struct convert_context *ctx,
- struct ablkcipher_request *req)
+ struct skcipher_request *req)
{
struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
@@ -866,13 +869,13 @@ static int crypt_convert_block(struct crypt_config *cc,
return r;
}

- ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
- 1 << SECTOR_SHIFT, iv);
+ skcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
+ 1 << SECTOR_SHIFT, iv);

if (bio_data_dir(ctx->bio_in) == WRITE)
- r = crypto_ablkcipher_encrypt(req);
+ r = crypto_skcipher_encrypt(req);
else
- r = crypto_ablkcipher_decrypt(req);
+ r = crypto_skcipher_decrypt(req);

if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
r = cc->iv_gen_ops->post(cc, iv, dmreq);
@@ -891,23 +894,23 @@ static void crypt_alloc_req(struct crypt_config *cc,
if (!ctx->req)
ctx->req = mempool_alloc(cc->req_pool, GFP_NOIO);

- ablkcipher_request_set_tfm(ctx->req, cc->tfms[key_index]);
+ skcipher_request_set_tfm(ctx->req, cc->tfms[key_index]);

/*
* Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
* requests if driver request queue is full.
*/
- ablkcipher_request_set_callback(ctx->req,
+ skcipher_request_set_callback(ctx->req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
kcryptd_async_done, dmreq_of_req(cc, ctx->req));
}

static void crypt_free_req(struct crypt_config *cc,
- struct ablkcipher_request *req, struct bio *base_bio)
+ struct skcipher_request *req, struct bio *base_bio)
{
struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);

- if ((struct ablkcipher_request *)(io + 1) != req)
+ if ((struct skcipher_request *)(io + 1) != req)
mempool_free(req, cc->req_pool);
}

@@ -1437,7 +1440,7 @@ static void crypt_free_tfms(struct crypt_config *cc)

for (i = 0; i < cc->tfms_count; i++)
if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) {
- crypto_free_ablkcipher(cc->tfms[i]);
+ crypto_free_skcipher(cc->tfms[i]);
cc->tfms[i] = NULL;
}

@@ -1450,13 +1453,13 @@ static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
unsigned i;
int err;

- cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *),
+ cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_skcipher *),
GFP_KERNEL);
if (!cc->tfms)
return -ENOMEM;

for (i = 0; i < cc->tfms_count; i++) {
- cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
+ cc->tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
if (IS_ERR(cc->tfms[i])) {
err = PTR_ERR(cc->tfms[i]);
crypt_free_tfms(cc);
@@ -1476,9 +1479,9 @@ static int crypt_setkey_allcpus(struct crypt_config *cc)
subkey_size = (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);

for (i = 0; i < cc->tfms_count; i++) {
- r = crypto_ablkcipher_setkey(cc->tfms[i],
- cc->key + (i * subkey_size),
- subkey_size);
+ r = crypto_skcipher_setkey(cc->tfms[i],
+ cc->key + (i * subkey_size),
+ subkey_size);
if (r)
err = r;
}
@@ -1645,7 +1648,7 @@ static int crypt_ctr_cipher(struct dm_target *ti,
}

/* Initialize IV */
- cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
+ cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
if (cc->iv_size)
/* at least a 64 bit sector number should fit in our buffer */
cc->iv_size = max(cc->iv_size,
@@ -1763,21 +1766,21 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
if (ret < 0)
goto bad;

- cc->dmreq_start = sizeof(struct ablkcipher_request);
- cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
+ cc->dmreq_start = sizeof(struct skcipher_request);
+ cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));

- if (crypto_ablkcipher_alignmask(any_tfm(cc)) < CRYPTO_MINALIGN) {
+ if (crypto_skcipher_alignmask(any_tfm(cc)) < CRYPTO_MINALIGN) {
/* Allocate the padding exactly */
iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
- & crypto_ablkcipher_alignmask(any_tfm(cc));
+ & crypto_skcipher_alignmask(any_tfm(cc));
} else {
/*
* If the cipher requires greater alignment than kmalloc
* alignment, we don't know the exact position of the
* initialization vector. We must assume worst case.
*/
- iv_size_padding = crypto_ablkcipher_alignmask(any_tfm(cc));
+ iv_size_padding = crypto_skcipher_alignmask(any_tfm(cc));
}

ret = -ENOMEM;
@@ -1922,7 +1925,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio)

io = dm_per_bio_data(bio, cc->per_bio_data_size);
crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
- io->ctx.req = (struct ablkcipher_request *)(io + 1);
+ io->ctx.req = (struct skcipher_request *)(io + 1);

if (bio_data_dir(io->base_bio) == READ) {
if (kcryptd_io_read(io, GFP_NOWAIT))