KEYS: asymmetric: Move sm2 code into x509_public_key

The sm2 certificate requires a modified digest.  Move the code
for the hashing from the signature verification path into the
code where we generate the digest.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 21 insertions, 8 deletions

diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
index 0b4943a4592b..6fdfc82e23a8 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -6,13 +6,15 @@
  */
 
 #define pr_fmt(fmt) "X.509: "fmt
+#include <crypto/hash.h>
+#include <crypto/sm2.h>
+#include <keys/asymmetric-parser.h>
+#include <keys/asymmetric-subtype.h>
+#include <keys/system_keyring.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
-#include <keys/asymmetric-subtype.h>
-#include <keys/asymmetric-parser.h>
-#include <keys/system_keyring.h>
-#include <crypto/hash.h>
+#include <linux/string.h>
 #include "asymmetric_keys.h"
 #include "x509_parser.h"
 
@@ -30,9 +32,6 @@ int x509_get_sig_params(struct x509_certificate *cert)
 
 	pr_devel("==>%s()\n", __func__);
 
-	sig->data = cert->tbs;
-	sig->data_size = cert->tbs_size;
-
 	sig->s = kmemdup(cert->raw_sig, cert->raw_sig_size, GFP_KERNEL);
 	if (!sig->s)
 		return -ENOMEM;
@@ -65,7 +64,21 @@ int x509_get_sig_params(struct x509_certificate *cert)
 
 	desc->tfm = tfm;
 
-	ret = crypto_shash_digest(desc, cert->tbs, cert->tbs_size, sig->digest);
+	if (strcmp(cert->pub->pkey_algo, "sm2") == 0) {
+		ret = strcmp(sig->hash_algo, "sm3") != 0 ? -EINVAL :
+		      crypto_shash_init(desc) ?:
+		      sm2_compute_z_digest(desc, cert->pub->key,
+					   cert->pub->keylen, sig->digest) ?:
+		      crypto_shash_init(desc) ?:
+		      crypto_shash_update(desc, sig->digest,
+					  sig->digest_size) ?:
+		      crypto_shash_finup(desc, cert->tbs, cert->tbs_size,
+					 sig->digest);
+	} else {
+		ret = crypto_shash_digest(desc, cert->tbs, cert->tbs_size,
+					  sig->digest);
+	}
+
 	if (ret < 0)
 		goto error_2;