return field_size;
}
+size_t SM2_plaintext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len)
+{
+ const size_t field_size = EC_field_size(EC_KEY_get0_group(key));
+ const size_t md_size = EVP_MD_size(digest);
+
+ const size_t overhead = 10 + 2 * field_size + md_size;
+ if(msg_len <= overhead)
+ return 0;
+
+ return msg_len - overhead;
+}
+
size_t SM2_ciphertext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len)
{
- return 10 + 2 * EC_field_size(EC_KEY_get0_group(key)) +
- EVP_MD_size(digest) + msg_len;
+ const size_t field_size = EC_field_size(EC_KEY_get0_group(key));
+ const size_t md_size = EVP_MD_size(digest);
+ return 10 + 2 * field_size + md_size + msg_len;
}
int SM2_encrypt(const EC_KEY *key,
goto done;
rc = 1;
+ *ptext_len = msg_len;
done: