Always try to set ASN.1 parameters for CMS.

Try to set the ASN.1 parameters for CMS encryption even if the IV
length is zero as the underlying cipher should still set the type.

This will correctly result in errors if an attempt is made to use
an unsupported cipher type.
Reviewed-by: NRich Salz <rsalz@openssl.org>

crypto/cms/cms_enc.c

@@ -176,17 +176,20 @@ BIO *cms_EncryptedContent_init_bio(CMS_EncryptedContentInfo *ec)
         goto err;
     }
 
-    if (piv) {
-        calg->parameter = ASN1_TYPE_new();
-        if (calg->parameter == NULL) {
-            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
-            goto err;
-        }
-        if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) {
-            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
-                   CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
-            goto err;
-        }
+    calg->parameter = ASN1_TYPE_new();
+    if (calg->parameter == NULL) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
+        goto err;
+    }
+    if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+               CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
+        goto err;
+    }
+    /* If paremeter type not set omit parameter */
+    if (calg->parameter->type == V_ASN1_UNDEF) {
+        ASN1_TYPE_free(calg->parameter);
+        calg->parameter = NULL;
     }
     ok = 1;