[RFC 4/7] crypto: use crypto_shash instead of crypto_hash incryptd hash

From: Huang Ying
Date: Thu Jun 11 2009 - 03:11:20 EST


crypto_hash interface has some issue and will be replaced by
crypto_shash. This patch replace crypto_hash in cryptd hash with
crypto_shash.

Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>

---
crypto/cryptd.c | 118 ++++++++++++++++++++++++++++++++++----------------------
1 file changed, 73 insertions(+), 45 deletions(-)

--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -14,12 +14,12 @@
#include <crypto/internal/hash.h>
#include <crypto/cryptd.h>
#include <crypto/crypto_wq.h>
+#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
-#include <linux/scatterlist.h>
#include <linux/sched.h>
#include <linux/slab.h>

@@ -48,11 +48,12 @@ struct cryptd_blkcipher_request_ctx {
};

struct cryptd_hash_ctx {
- struct crypto_hash *child;
+ struct crypto_shash *child;
};

struct cryptd_hash_request_ctx {
crypto_completion_t complete;
+ struct shash_desc desc;
};

static void cryptd_queue_worker(struct work_struct *work);
@@ -334,15 +335,15 @@ static int cryptd_hash_init_tfm(struct c
struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);
struct crypto_spawn *spawn = &ictx->spawn;
struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(tfm);
- struct crypto_hash *cipher;
+ struct crypto_shash *cipher;

- cipher = crypto_spawn_hash(spawn);
+ cipher = crypto_spawn_shash(spawn);
if (IS_ERR(cipher))
return PTR_ERR(cipher);

ctx->child = cipher;
- tfm->crt_ahash.reqsize =
- sizeof(struct cryptd_hash_request_ctx);
+ tfm->crt_ahash.reqsize = sizeof(struct cryptd_hash_request_ctx) +
+ crypto_shash_descsize(cipher);
return 0;
}

@@ -350,22 +351,22 @@ static void cryptd_hash_exit_tfm(struct
{
struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(tfm);

- crypto_free_hash(ctx->child);
+ crypto_free_shash(ctx->child);
}

static int cryptd_hash_setkey(struct crypto_ahash *parent,
const u8 *key, unsigned int keylen)
{
struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(parent);
- struct crypto_hash *child = ctx->child;
+ struct crypto_shash *child = ctx->child;
int err;

- crypto_hash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
- crypto_hash_set_flags(child, crypto_ahash_get_flags(parent) &
- CRYPTO_TFM_REQ_MASK);
- err = crypto_hash_setkey(child, key, keylen);
- crypto_ahash_set_flags(parent, crypto_hash_get_flags(child) &
- CRYPTO_TFM_RES_MASK);
+ crypto_shash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+ crypto_shash_set_flags(child, crypto_ahash_get_flags(parent) &
+ CRYPTO_TFM_REQ_MASK);
+ err = crypto_shash_setkey(child, key, keylen);
+ crypto_ahash_set_flags(parent, crypto_shash_get_flags(child) &
+ CRYPTO_TFM_RES_MASK);
return err;
}

@@ -386,20 +387,21 @@ static int cryptd_hash_enqueue(struct ah
static void cryptd_hash_init(struct crypto_async_request *req_async, int err)
{
struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
- struct crypto_hash *child = ctx->child;
+ struct crypto_shash *child = ctx->child;
struct ahash_request *req = ahash_request_cast(req_async);
struct cryptd_hash_request_ctx *rctx;
- struct hash_desc desc;
+ struct shash_desc *desc;

rctx = ahash_request_ctx(req);

if (unlikely(err == -EINPROGRESS))
goto out;

- desc.tfm = child;
- desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ desc = &rctx->desc;
+ desc->tfm = child;
+ desc->flags = req->base.flags | CRYPTO_TFM_REQ_MAY_SLEEP;

- err = crypto_hash_crt(child)->init(&desc);
+ err = crypto_shash_init(desc);

req->base.complete = rctx->complete;

@@ -416,23 +418,23 @@ static int cryptd_hash_init_enqueue(stru

static void cryptd_hash_update(struct crypto_async_request *req_async, int err)
{
- struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
- struct crypto_hash *child = ctx->child;
struct ahash_request *req = ahash_request_cast(req_async);
struct cryptd_hash_request_ctx *rctx;
- struct hash_desc desc;
+ struct shash_desc *desc;
+ struct crypto_hash_walk walk;
+ int nbytes;

rctx = ahash_request_ctx(req);

if (unlikely(err == -EINPROGRESS))
goto out;

- desc.tfm = child;
- desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ desc = &rctx->desc;

- err = crypto_hash_crt(child)->update(&desc,
- req->src,
- req->nbytes);
+ for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+ nbytes = crypto_hash_walk_done(&walk, nbytes))
+ nbytes = crypto_shash_update(desc, walk.data, nbytes);
+ err = nbytes;

req->base.complete = rctx->complete;

@@ -449,21 +451,18 @@ static int cryptd_hash_update_enqueue(st

static void cryptd_hash_final(struct crypto_async_request *req_async, int err)
{
- struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
- struct crypto_hash *child = ctx->child;
struct ahash_request *req = ahash_request_cast(req_async);
struct cryptd_hash_request_ctx *rctx;
- struct hash_desc desc;
+ struct shash_desc *desc;

rctx = ahash_request_ctx(req);

if (unlikely(err == -EINPROGRESS))
goto out;

- desc.tfm = child;
- desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ desc = &rctx->desc;

- err = crypto_hash_crt(child)->final(&desc, req->result);
+ err = crypto_shash_final(desc, req->result);

req->base.complete = rctx->complete;

@@ -481,23 +480,49 @@ static int cryptd_hash_final_enqueue(str
static void cryptd_hash_digest(struct crypto_async_request *req_async, int err)
{
struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
- struct crypto_hash *child = ctx->child;
- struct ahash_request *req = ahash_request_cast(req_async);
+ struct crypto_shash *child = ctx->child;
+ struct ahash_request *req = ahash_request_cast(req_async);
struct cryptd_hash_request_ctx *rctx;
- struct hash_desc desc;
+ struct shash_desc *desc;
+ struct crypto_hash_walk walk;
+ int nbytes;
+ unsigned int n = req->nbytes;
+ struct scatterlist *sg = req->src;
+ unsigned int offset = sg->offset;

rctx = ahash_request_ctx(req);

if (unlikely(err == -EINPROGRESS))
goto out;

- desc.tfm = child;
- desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ desc = &rctx->desc;
+ desc->tfm = child;
+ desc->flags = req->base.flags | CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ if (n < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
+ void *data;
+
+ data = crypto_kmap(sg_page(sg), 0);
+ err = crypto_shash_digest(desc, data + offset, n,
+ req->result);
+ crypto_kunmap(data, 0);
+ crypto_yield(desc->flags);
+ goto out;
+ }

- err = crypto_hash_crt(child)->digest(&desc,
- req->src,
- req->nbytes,
- req->result);
+ err = crypto_shash_init(desc);
+ if (err)
+ goto out;
+
+ for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+ nbytes = crypto_hash_walk_done(&walk, nbytes))
+ nbytes = crypto_shash_update(desc, walk.data, nbytes);
+ if (nbytes) {
+ err = nbytes;
+ goto out;
+ }
+
+ err = crypto_shash_final(desc, req->result);

req->base.complete = rctx->complete;

@@ -517,12 +542,15 @@ static struct crypto_instance *cryptd_al
{
struct crypto_instance *inst;
struct crypto_alg *alg;
+ struct shash_alg *salg;

- alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_HASH,
- CRYPTO_ALG_TYPE_HASH_MASK);
+ alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_SHASH,
+ CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
return ERR_PTR(PTR_ERR(alg));

+ salg = __crypto_shash_alg(alg);
+
inst = cryptd_alloc_instance(alg, queue);
if (IS_ERR(inst))
goto out_put_alg;
@@ -530,7 +558,7 @@ static struct crypto_instance *cryptd_al
inst->alg.cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC;
inst->alg.cra_type = &crypto_ahash_type;

- inst->alg.cra_ahash.digestsize = alg->cra_hash.digestsize;
+ inst->alg.cra_ahash.digestsize = salg->digestsize;
inst->alg.cra_ctxsize = sizeof(struct cryptd_hash_ctx);

inst->alg.cra_init = cryptd_hash_init_tfm;


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