crypto: rsa-pkcs1pad - Require hash to be present

The only user of rsa-pkcs1pad always uses the hash so there is
no reason to support the case of not having a hash.

This patch also changes the digest info lookup so that it is
only done once during template instantiation rather than on each
operation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2016-06-29 19:32:23 +08:00
parent 127827b9c2
commit c0d20d22e0

View File

@ -92,13 +92,12 @@ static const struct rsa_asn1_template *rsa_lookup_asn1(const char *name)
struct pkcs1pad_ctx {
struct crypto_akcipher *child;
const char *hash_name;
unsigned int key_size;
};
struct pkcs1pad_inst_ctx {
struct crypto_akcipher_spawn spawn;
const char *hash_name;
const struct rsa_asn1_template *digest_info;
};
struct pkcs1pad_request {
@ -416,20 +415,16 @@ static int pkcs1pad_sign(struct akcipher_request *req)
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
const struct rsa_asn1_template *digest_info = NULL;
struct akcipher_instance *inst = akcipher_alg_instance(tfm);
struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
const struct rsa_asn1_template *digest_info = ictx->digest_info;
int err;
unsigned int ps_end, digest_size = 0;
if (!ctx->key_size)
return -EINVAL;
if (ctx->hash_name) {
digest_info = rsa_lookup_asn1(ctx->hash_name);
if (!digest_info)
return -EINVAL;
digest_size = digest_info->size;
}
if (req->src_len + digest_size > ctx->key_size - 11)
return -EOVERFLOW;
@ -462,10 +457,8 @@ static int pkcs1pad_sign(struct akcipher_request *req)
memset(req_ctx->in_buf + 1, 0xff, ps_end - 1);
req_ctx->in_buf[ps_end] = 0x00;
if (digest_info) {
memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data,
digest_info->size);
}
pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
ctx->key_size - 1 - req->src_len, req->src);
@ -499,7 +492,9 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
const struct rsa_asn1_template *digest_info;
struct akcipher_instance *inst = akcipher_alg_instance(tfm);
struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
const struct rsa_asn1_template *digest_info = ictx->digest_info;
unsigned int pos;
if (err == -EOVERFLOW)
@ -527,17 +522,11 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
goto done;
pos++;
if (ctx->hash_name) {
digest_info = rsa_lookup_asn1(ctx->hash_name);
if (!digest_info)
goto done;
if (memcmp(req_ctx->out_buf + pos, digest_info->data,
digest_info->size))
goto done;
pos += digest_info->size;
}
err = 0;
@ -626,12 +615,11 @@ static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm)
struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
struct crypto_akcipher *child_tfm;
child_tfm = crypto_spawn_akcipher(akcipher_instance_ctx(inst));
child_tfm = crypto_spawn_akcipher(&ictx->spawn);
if (IS_ERR(child_tfm))
return PTR_ERR(child_tfm);
ctx->child = child_tfm;
ctx->hash_name = ictx->hash_name;
return 0;
}
@ -648,12 +636,12 @@ static void pkcs1pad_free(struct akcipher_instance *inst)
struct crypto_akcipher_spawn *spawn = &ctx->spawn;
crypto_drop_akcipher(spawn);
kfree(ctx->hash_name);
kfree(inst);
}
static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
{
const struct rsa_asn1_template *digest_info;
struct crypto_attr_type *algt;
struct akcipher_instance *inst;
struct pkcs1pad_inst_ctx *ctx;
@ -676,7 +664,11 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
hash_name = crypto_attr_alg_name(tb[2]);
if (IS_ERR(hash_name))
hash_name = NULL;
return PTR_ERR(hash_name);
digest_info = rsa_lookup_asn1(hash_name);
if (!digest_info)
return -EINVAL;
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
@ -684,7 +676,7 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
ctx = akcipher_instance_ctx(inst);
spawn = &ctx->spawn;
ctx->hash_name = hash_name ? kstrdup(hash_name, GFP_KERNEL) : NULL;
ctx->digest_info = digest_info;
crypto_set_spawn(&spawn->base, akcipher_crypto_instance(inst));
err = crypto_grab_akcipher(spawn, rsa_alg_name, 0,
@ -696,27 +688,14 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
err = -ENAMETOOLONG;
if (!hash_name) {
if (snprintf(inst->alg.base.cra_name,
CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
rsa_alg->base.cra_name) >=
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 ||
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;
} else {
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 ||
snprintf(inst->alg.base.cra_driver_name,
CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s,%s)",
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_free_hash;
}
goto out_drop_alg;
inst->alg.base.cra_flags = rsa_alg->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
@ -738,12 +717,10 @@ static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
err = akcipher_register_instance(tmpl, inst);
if (err)
goto out_free_hash;
goto out_drop_alg;
return 0;
out_free_hash:
kfree(ctx->hash_name);
out_drop_alg:
crypto_drop_akcipher(spawn);
out_free_inst: