Commit 3b2f6df0 authored by Herbert Xu's avatar Herbert Xu
Browse files

crypto: hash - Export shash through ahash 



This patch allows shash algorithms to be used through the ahash
interface.  This is required before we can convert digest algorithms
over to shash.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 7b5a080b

crypto/shash.c

+143 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
 *

 */



#include <crypto/scatterwalk.h>

#include <crypto/internal/hash.h>

#include <linux/err.h>

#include <linux/kernel.h>
@@ -17,11 +18,15 @@ 
#include <linux/slab.h>

#include <linux/seq_file.h>



static const struct crypto_type crypto_shash_type;



static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm)

{

	return container_of(tfm, struct crypto_shash, base);

}



#include "internal.h"



static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,

				  unsigned int keylen)

{
@@ -167,6 +172,142 @@ int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 
}

EXPORT_SYMBOL_GPL(crypto_shash_digest);



static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,

			      unsigned int keylen)

{

	struct crypto_shash **ctx = crypto_ahash_ctx(tfm);



	return crypto_shash_setkey(*ctx, key, keylen);

}



static int shash_async_init(struct ahash_request *req)

{

	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));

	struct shash_desc *desc = ahash_request_ctx(req);



	desc->tfm = *ctx;

	desc->flags = req->base.flags;



	return crypto_shash_init(desc);

}



static int shash_async_update(struct ahash_request *req)

{

	struct shash_desc *desc = ahash_request_ctx(req);

	struct crypto_hash_walk walk;

	int 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);



	return nbytes;

}



static int shash_async_final(struct ahash_request *req)

{

	return crypto_shash_final(ahash_request_ctx(req), req->result);

}



static int shash_async_digest(struct ahash_request *req)

{

	struct scatterlist *sg = req->src;

	unsigned int offset = sg->offset;

	unsigned int nbytes = req->nbytes;

	int err;



	if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {

		struct crypto_shash **ctx =

			crypto_ahash_ctx(crypto_ahash_reqtfm(req));

		struct shash_desc *desc = ahash_request_ctx(req);

		void *data;



		desc->tfm = *ctx;

		desc->flags = req->base.flags;



		data = crypto_kmap(sg_page(sg), 0);

		err = crypto_shash_digest(desc, data + offset, nbytes,

					  req->result);

		crypto_kunmap(data, 0);

		crypto_yield(desc->flags);

		goto out;

	}



	err = shash_async_init(req);

	if (err)

		goto out;



	err = shash_async_update(req);

	if (err)

		goto out;



	err = shash_async_final(req);



out:

	return err;

}



static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)

{

	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);



	crypto_free_shash(*ctx);

}



static int crypto_init_shash_ops_async(struct crypto_tfm *tfm)

{

	struct crypto_alg *calg = tfm->__crt_alg;

	struct shash_alg *alg = __crypto_shash_alg(calg);

	struct ahash_tfm *crt = &tfm->crt_ahash;

	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);

	struct crypto_shash *shash;



	if (!crypto_mod_get(calg))

		return -EAGAIN;



	shash = __crypto_shash_cast(crypto_create_tfm(

		calg, &crypto_shash_type));

	if (IS_ERR(shash)) {

		crypto_mod_put(calg);

		return PTR_ERR(shash);

	}



	*ctx = shash;

	tfm->exit = crypto_exit_shash_ops_async;



	crt->init = shash_async_init;

	crt->update = shash_async_update;

	crt->final  = shash_async_final;

	crt->digest = shash_async_digest;

	crt->setkey = shash_async_setkey;



	crt->digestsize = alg->digestsize;

	crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);



	return 0;

}



static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)

{

	switch (mask & CRYPTO_ALG_TYPE_MASK) {

	case CRYPTO_ALG_TYPE_AHASH_MASK:

		return crypto_init_shash_ops_async(tfm);

	}



	return -EINVAL;

}



static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,

					 u32 mask)

{

	switch (mask & CRYPTO_ALG_TYPE_MASK) {

	case CRYPTO_ALG_TYPE_AHASH_MASK:

		return sizeof(struct crypto_shash *);

	}



	return 0;

}



static int crypto_shash_init_tfm(struct crypto_tfm *tfm,

				 const struct crypto_type *frontend)

{
@@ -194,7 +335,9 @@ static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 
}



static const struct crypto_type crypto_shash_type = {

	.ctxsize = crypto_shash_ctxsize,

	.extsize = crypto_shash_extsize,

	.init = crypto_init_shash_ops,

	.init_tfm = crypto_shash_init_tfm,

#ifdef CONFIG_PROC_FS

	.show = crypto_shash_show,

include/linux/crypto.h

+1 −1
Original line number Diff line number Diff line
@@ -38,8 +38,8 @@ 
#define CRYPTO_ALG_TYPE_DIGEST		0x00000008

#define CRYPTO_ALG_TYPE_HASH		0x00000009

#define CRYPTO_ALG_TYPE_AHASH		0x0000000a

#define CRYPTO_ALG_TYPE_SHASH		0x0000000b

#define CRYPTO_ALG_TYPE_RNG		0x0000000c

#define CRYPTO_ALG_TYPE_SHASH		0x0000000d



#define CRYPTO_ALG_TYPE_HASH_MASK	0x0000000e

#define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000c