[PATCH v3 13/18] crypto: rsa-psspad: Get signature parameters from a given signature

Varad Gautam
2021-04-20T11:48:14Z

Implement akcipher_alg->set_sig_params for rsassa-psspad to receive the
salt length and MGF hash function for the signature being verified.

Signed-off-by: Varad Gautam <varad.gautam@suse.com>
---
crypto/rsa-psspad.c | 21 ++++++++++++++++++++-
include/crypto/internal/rsa-common.h | 2 ++
2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/crypto/rsa-psspad.c b/crypto/rsa-psspad.c
index 40bb6d1dd2067..0a9c0f9e9f0fe 100644
--- a/crypto/rsa-psspad.c
+++ b/crypto/rsa-psspad.c
@@ -9,6 +9,7 @@
#include <crypto/hash.h>
#include <crypto/internal/akcipher.h>
#include <crypto/internal/rsa-common.h>
+#include <crypto/public_key.h>

static bool psspad_check_hash_algo(const char *hash_algo)
{
@@ -52,6 +53,23 @@ static void psspad_free_shash(struct crypto_shash *hash_tfm, struct shash_desc *
crypto_free_shash(hash_tfm);
}

+static int psspad_set_sig_params(struct crypto_akcipher *tfm,
+ const void *sig,
+ unsigned int siglen)
+{
+ struct akcipher_instance *inst = akcipher_alg_instance(tfm);
+ struct rsapad_inst_ctx *ictx = akcipher_instance_ctx(inst);
+ const struct public_key_signature *s = sig;
+
+ if (!sig)
+ return -EINVAL;
+
+ ictx->salt_len = s->salt_length;
+ ictx->mgf_hash_algo = s->mgf_hash_algo;
+
+ return 0;
+}
+
static int psspad_s_v_e_d(struct akcipher_request *req)
{
return -EOPNOTSUPP;
@@ -67,7 +85,8 @@ static struct akcipher_alg psspad_alg = {
.verify = psspad_s_v_e_d,
.set_pub_key = rsapad_set_pub_key,
.set_priv_key = rsapad_set_priv_key,
- .max_size = rsapad_get_max_size
+ .max_size = rsapad_get_max_size,
+ .set_sig_params = psspad_set_sig_params
};

static int psspad_create(struct crypto_template *tmpl, struct rtattr **tb)
diff --git a/include/crypto/internal/rsa-common.h b/include/crypto/internal/rsa-common.h
index 4fa3cf5a989cc..8b7ba0174d5bf 100644
--- a/include/crypto/internal/rsa-common.h
+++ b/include/crypto/internal/rsa-common.h
@@ -26,6 +26,8 @@ struct rsapad_tfm_ctx {
struct rsapad_inst_ctx {
struct crypto_akcipher_spawn spawn;
const struct rsa_asn1_template *digest_info;
+ u16 salt_len;
+ const char *mgf_hash_algo;
};

struct rsapad_akciper_req_ctx {
--
2.30.2