[Minor] Improve encryption requirement error code

src/libutil/http.c

@@ -45,6 +45,7 @@ enum rspamd_http_priv_flags {
 	RSPAMD_HTTP_CONN_FLAG_NEW_HEADER = 1 << 1,
 	RSPAMD_HTTP_CONN_FLAG_RESETED = 1 << 2,
 	RSPAMD_HTTP_CONN_FLAG_TOO_LARGE = 1 << 3,
+	RSPAMD_HTTP_CONN_FLAG_ENCRYPTION_NEEDED = 1 << 4,
 };
 
 #define IS_CONN_ENCRYPTED(c) ((c)->flags & RSPAMD_HTTP_CONN_FLAG_ENCRYPTED)
@@ -915,6 +916,7 @@ rspamd_http_on_message_complete (http_parser * parser)
 	priv = conn->priv;
 
 	if ((conn->opts & RSPAMD_HTTP_REQUIRE_ENCRYPTION) && !IS_CONN_ENCRYPTED (priv)) {
+		priv->flags |= RSPAMD_HTTP_CONN_FLAG_ENCRYPTION_NEEDED;
 		msg_err ("unencrypted connection when encryption has been requested");
 		return -1;
 	}
@@ -1185,8 +1187,12 @@ rspamd_http_event_handler (int fd, short what, gpointer ud)
 							"Request entity too large: %zu",
 							(size_t)priv->parser.content_length);
 				}
+				else if (priv->flags & RSPAMD_HTTP_CONN_FLAG_ENCRYPTION_NEEDED) {
+					err = g_error_new (HTTP_ERROR, 400,
+							"Encryption required");
+				}
 				else {
-					err = g_error_new (HTTP_ERROR, priv->parser.http_errno,
+					err = g_error_new (HTTP_ERROR, 500 + priv->parser.http_errno,
 							"HTTP parser error: %s",
 							http_errno_description (priv->parser.http_errno));
 				}