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
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+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,
+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