Commit 0708bb43 authored by Eric Biggers's avatar Eric Biggers Committed by Herbert Xu
Browse files

crypto: rsa-pkcs1pad - simplify error handling in pkcs1pad_create() 



Simplify the error handling in pkcs1pad_create() by taking advantage of
crypto_grab_akcipher() now handling an ERR_PTR() name and by taking
advantage of crypto_drop_akcipher() now accepting (as a no-op) a spawn
that hasn't been grabbed yet.

While we're at it, also simplify the way the hash_name optional argument
is handled.  We only need to check whether it's present in one place,
and we can just assign directly to ctx->digest_info.

Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 07b24c7c

crypto/rsa-pkcs1pad.c

+20 −39
Original line number Diff line number Diff line
@@ -596,14 +596,11 @@ static void pkcs1pad_free(struct akcipher_instance *inst) 


static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)

{

	const struct rsa_asn1_template *digest_info;

	struct crypto_attr_type *algt;

	u32 mask;

	struct akcipher_instance *inst;

	struct pkcs1pad_inst_ctx *ctx;

	struct crypto_akcipher_spawn *spawn;

	struct akcipher_alg *rsa_alg;

	const char *rsa_alg_name;

	const char *hash_name;

	int err;
@@ -616,60 +613,49 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb) 


	mask = crypto_requires_sync(algt->type, algt->mask);



	rsa_alg_name = crypto_attr_alg_name(tb[1]);

	if (IS_ERR(rsa_alg_name))

		return PTR_ERR(rsa_alg_name);



	hash_name = crypto_attr_alg_name(tb[2]);

	if (IS_ERR(hash_name))

		hash_name = NULL;



	if (hash_name) {

		digest_info = rsa_lookup_asn1(hash_name);

		if (!digest_info)

			return -EINVAL;

	} else

		digest_info = NULL;



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

	if (!inst)

		return -ENOMEM;



	ctx = akcipher_instance_ctx(inst);

	spawn = &ctx->spawn;

	ctx->digest_info = digest_info;



	err = crypto_grab_akcipher(spawn, akcipher_crypto_instance(inst),

				   rsa_alg_name, 0, mask);

	err = crypto_grab_akcipher(&ctx->spawn, akcipher_crypto_instance(inst),

				   crypto_attr_alg_name(tb[1]), 0, mask);

	if (err)

		goto out_free_inst;

		goto err_free_inst;



	rsa_alg = crypto_spawn_akcipher_alg(spawn);

	rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn);



	err = -ENAMETOOLONG;



	if (!hash_name) {

	hash_name = crypto_attr_alg_name(tb[2]);

	if (IS_ERR(hash_name)) {

		if (snprintf(inst->alg.base.cra_name,

			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",

			     rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)

			goto out_drop_alg;

			goto err_free_inst;



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

			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",

			     rsa_alg->base.cra_driver_name) >=

			     CRYPTO_MAX_ALG_NAME)

			goto out_drop_alg;

			goto err_free_inst;

	} else {

		ctx->digest_info = rsa_lookup_asn1(hash_name);

		if (!ctx->digest_info) {

			err = -EINVAL;

			goto err_free_inst;

		}



		if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,

			     "pkcs1pad(%s,%s)", rsa_alg->base.cra_name,

			     hash_name) >= CRYPTO_MAX_ALG_NAME)

			goto out_drop_alg;

			goto err_free_inst;



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

			     CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s,%s)",

			     rsa_alg->base.cra_driver_name,

			     hash_name) >= CRYPTO_MAX_ALG_NAME)

			goto out_drop_alg;

			goto err_free_inst;

	}



	inst->alg.base.cra_flags = rsa_alg->base.cra_flags & CRYPTO_ALG_ASYNC;
@@ -691,15 +677,10 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb) 
	inst->free = pkcs1pad_free;



	err = akcipher_register_instance(tmpl, inst);

	if (err)

		goto out_drop_alg;



	return 0;



out_drop_alg:

	crypto_drop_akcipher(spawn);

out_free_inst:

	kfree(inst);

	if (err) {

err_free_inst:

		pkcs1pad_free(inst);

	}

	return err;

}

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