Commit 1472e5eb authored by Herbert Xu's avatar Herbert Xu
Browse files

[CRYPTO] gcm: Use crypto_grab_skcipher 



This patch converts the gcm algorithm over to crypto_grab_skcipher
which is a prerequisite for IV generation.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent d00aa19b

crypto/gcm.c

+23 −26
Original line number Diff line number Diff line
@@ -8,8 +8,8 @@ 
 * by the Free Software Foundation.

 */



#include <crypto/algapi.h>

#include <crypto/gf128mul.h>

#include <crypto/internal/skcipher.h>

#include <crypto/scatterwalk.h>

#include <linux/completion.h>

#include <linux/err.h>
@@ -18,10 +18,8 @@ 
#include <linux/module.h>

#include <linux/slab.h>



#include "internal.h"



struct gcm_instance_ctx {

	struct crypto_spawn ctr;

	struct crypto_skcipher_spawn ctr;

};



struct crypto_gcm_ctx {
@@ -386,7 +384,7 @@ static int crypto_gcm_init_tfm(struct crypto_tfm *tfm) 
	unsigned long align;

	int err;



	ctr = crypto_spawn_ablkcipher(&ictx->ctr);

	ctr = crypto_spawn_skcipher(&ictx->ctr);

	err = PTR_ERR(ctr);

	if (IS_ERR(ctr))

		return err;
@@ -431,15 +429,22 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, 
	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)

		return ERR_PTR(-EINVAL);



	ctr = crypto_alg_mod_lookup(ctr_name, CRYPTO_ALG_TYPE_BLKCIPHER,

				    CRYPTO_ALG_TYPE_MASK);

	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);

	if (!inst)

		return ERR_PTR(-ENOMEM);



	if (IS_ERR(ctr))

		return ERR_PTR(PTR_ERR(ctr));

	ctx = crypto_instance_ctx(inst);

	crypto_set_skcipher_spawn(&ctx->ctr, inst);

	err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,

				   crypto_requires_sync(algt->type,

							algt->mask));

	if (err)

		goto err_free_inst;



	ctr = crypto_skcipher_spawn_alg(&ctx->ctr);



	/* We only support 16-byte blocks. */

	if ((ctr->cra_type == &crypto_blkcipher_type ?

	     ctr->cra_blkcipher.ivsize : ctr->cra_ablkcipher.ivsize) != 16)

	if (ctr->cra_ablkcipher.ivsize != 16)

		goto out_put_ctr;



	/* Not a stream cipher? */
@@ -447,25 +452,16 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, 
	if (ctr->cra_blocksize != 1)

		goto out_put_ctr;



	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);

	err = -ENOMEM;

	if (!inst)

		goto out_put_ctr;



	err = -ENAMETOOLONG;

	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,

		     "gcm_base(%s)", ctr->cra_driver_name) >=

	    CRYPTO_MAX_ALG_NAME)

		goto err_free_inst;



	ctx = crypto_instance_ctx(inst);

	err = crypto_init_spawn(&ctx->ctr, ctr, inst, CRYPTO_ALG_TYPE_MASK);

	if (err)

		goto err_free_inst;

		goto out_put_ctr;



	memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME);



	inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;

	inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;

	inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC;

	inst->alg.cra_priority = ctr->cra_priority;

	inst->alg.cra_blocksize = 1;

	inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1);
@@ -480,11 +476,12 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, 
	inst->alg.cra_aead.decrypt = crypto_gcm_decrypt;



out:

	crypto_mod_put(ctr);

	return inst;



out_put_ctr:

	crypto_drop_skcipher(&ctx->ctr);

err_free_inst:

	kfree(inst);

out_put_ctr:

	inst = ERR_PTR(err);

	goto out;

}
@@ -516,7 +513,7 @@ static void crypto_gcm_free(struct crypto_instance *inst) 
{

	struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);



	crypto_drop_spawn(&ctx->ctr);

	crypto_drop_skcipher(&ctx->ctr);

	kfree(inst);

}