mgmtd: validate notify selectors to be xpaths that result to nodes

Also, only message interested backend clients about a path removal when last
supporting session is being removed from a given notification path.

Signed-off-by: Christian Hopps <chopps@labn.net>

diff --git a/mgmtd/mgmt_fe_adapter.c b/mgmtd/mgmt_fe_adapter.c
index 39686091e1d13e6b98d0f739b94e03f6215607b3..7c632ef230aead3f538f187b21b00f101765d09d 100644 (file)
--- a/mgmtd/mgmt_fe_adapter.c
+++ b/mgmtd/mgmt_fe_adapter.c
@@ -119,8 +119,8 @@ static uint64_t mgmt_fe_ns_string_remove_session(struct ns_string_head *head,
                if (!node)
                        continue;
                list_delete_node(ns->sessions, node);
-               clients |= mgmt_be_interested_clients(ns->s, MGMT_BE_XPATH_SUBSCR_TYPE_OPER);
                if (list_isempty(ns->sessions)) {
+                       clients |= mgmt_be_interested_clients(ns->s, MGMT_BE_XPATH_SUBSCR_TYPE_OPER);
                        ns_string_del(head, ns);
                        mgmt_fe_free_ns_string(ns);
                }
@@ -1642,6 +1642,7 @@ static void fe_adapter_handle_notify_select(struct mgmt_fe_session_ctx *session,
 {
        struct mgmt_msg_notify_select *msg = __msg;
        uint64_t req_id = msg->req_id;
+       struct nb_node **nb_nodes;
        const char **selectors = NULL;
        const char **new;
        const char **sp;
@@ -1656,6 +1657,19 @@ static void fe_adapter_handle_notify_select(struct mgmt_fe_session_ctx *session,
                        return;
                }
        }
+
+       /* Validate all selectors, they need to resolve to actual northbound_nodes */
+       darr_foreach_p (selectors, sp) {
+               nb_nodes = nb_nodes_find(*sp);
+               if (!nb_nodes) {
+                       fe_adapter_send_error(session, req_id, false, -EINVAL,
+                                             "Selector doesn't resolve to a node: %s", *sp);
+                       darr_free_free(selectors);
+                       return;
+               }
+               darr_free(nb_nodes);
+       }
+
        if (DEBUG_MODE_CHECK(&mgmt_debug_fe, DEBUG_MODE_ALL)) {
                selstr = frrstr_join(selectors, darr_len(selectors), ", ");
                if (!selstr)
@@ -1932,6 +1946,11 @@ void mgmt_fe_adapter_send_notify(struct mgmt_msg_notify_data *msg, size_t msglen
                }
        }
 
+       /*
+        * XXX if `is_root` should only send to each session one time, the code
+        * below will send multiple times if a session has multiple selectors.
+        */
+
        frr_each (ns_string, &mgmt_fe_ns_strings, ns) {
                if (!is_root) {
                        len = strlen(ns->s);