isisd: support for snmp

Add support for read only mib objects from RFC4444.

Signed-off-by: Lynne Morrison <lynne@voltanet.io>
Signed-off-by: Karen Schoener <karen@voltanet.io>

1 files changed, 74 insertions, 0 deletions

diff --git a/isisd/isis_circuit.c b/isisd/isis_circuit.c
index 4aac3f8880..62822cbf89 100644
--- a/isisd/isis_circuit.c
+++ b/isisd/isis_circuit.c
@@ -71,6 +71,48 @@ DEFINE_HOOK(isis_if_new_hook, (struct interface *ifp), (ifp))
 int isis_if_new_hook(struct interface *);
 int isis_if_delete_hook(struct interface *);
 
+static int isis_circuit_smmp_id_gen(struct isis_circuit *circuit)
+{
+	struct vrf *vrf = vrf_lookup_by_id(VRF_DEFAULT);
+	struct isis *isis = NULL;
+	uint32_t id;
+	uint32_t i;
+
+	isis = isis_lookup_by_vrfid(vrf->vrf_id);
+	if (isis == NULL)
+		return 0;
+
+	id = isis->snmp_circuit_id_last;
+	id++;
+
+	/* find next unused entry */
+	for (i = 0; i < SNMP_CIRCUITS_MAX; i++) {
+		if (id >= SNMP_CIRCUITS_MAX) {
+			id = 0;
+			continue;
+		}
+
+		if (id == 0)
+			continue;
+
+		if (isis->snmp_circuits[id] == NULL)
+			break;
+
+		id++;
+	}
+
+	if (i == SNMP_CIRCUITS_MAX) {
+		zlog_warn("Could not allocate a smmp-circuit-id");
+		return 0;
+	}
+
+	isis->snmp_circuits[id] = circuit;
+	isis->snmp_circuit_id_last = id;
+	circuit->snmp_id = id;
+
+	return 1;
+}
+
 struct isis_circuit *isis_circuit_new(struct isis *isis)
 {
 	struct isis_circuit *circuit;
@@ -80,6 +122,12 @@ struct isis_circuit *isis_circuit_new(struct isis *isis)
 
 	circuit->isis = isis;
 	/*
+	 * Note: if snmp-id generation failed circuit will fail
+	 * up operation
+	 */
+	isis_circuit_smmp_id_gen(circuit);
+
+	/*
 	 * Default values
 	 */
 #ifndef FABRICD
@@ -150,11 +198,18 @@ struct isis_circuit *isis_circuit_new(struct isis *isis)
 
 void isis_circuit_del(struct isis_circuit *circuit)
 {
+	struct isis *isis = NULL;
+
 	if (!circuit)
 		return;
 
 	QOBJ_UNREG(circuit);
 
+	if (circuit->interface) {
+		isis = isis_lookup_by_vrfid(circuit->interface->vrf_id);
+		isis->snmp_circuits[circuit->snmp_id] = NULL;
+	}
+
 	isis_circuit_if_unbind(circuit, circuit->interface);
 
 	circuit_mt_finish(circuit);
@@ -609,6 +664,7 @@ int isis_circuit_up(struct isis_circuit *circuit)
 		return ISIS_OK;
 
 	if (circuit->is_passive) {
+		circuit->last_uptime = time(NULL);
 		/* make sure the union fields are initialized, else we
 		 * could end with garbage values from a previous circuit
 		 * type, which would then cause a segfault when building
@@ -623,6 +679,13 @@ int isis_circuit_up(struct isis_circuit *circuit)
 		return ISIS_OK;
 	}
 
+	if (circuit->snmp_id == 0) {
+		/* We cannot bring circuit up if does not have snmp-id */
+		flog_err(EC_ISIS_CONFIG,
+			 "No snnmp-id: there are too many circuits:");
+		return ISIS_ERROR;
+	}
+
 	if (circuit->area->lsp_mtu > isis_circuit_pdu_size(circuit)) {
 		flog_err(
 			EC_ISIS_CONFIG,
@@ -722,6 +785,8 @@ int isis_circuit_up(struct isis_circuit *circuit)
 
 	circuit->tx_queue = isis_tx_queue_new(circuit, send_lsp);
 
+	circuit->last_uptime = time(NULL);
+
 #ifndef FABRICD
 	/* send northbound notification */
 	isis_notif_if_state_change(circuit, false);
@@ -828,6 +893,15 @@ void isis_circuit_down(struct isis_circuit *circuit)
 		thread_cancel(&circuit->u.p2p.t_send_p2p_hello);
 	}
 
+	/*
+	 * All adjacencies have to be gone, delete snmp list
+	 * and reset snmpd idx generator
+	 */
+	if (circuit->snmp_adj_list != NULL)
+		list_delete(&circuit->snmp_adj_list);
+
+	circuit->snmp_adj_idx_gen = 0;
+
 	/* Cancel all active threads */
 	thread_cancel(&circuit->t_send_csnp[0]);
 	thread_cancel(&circuit->t_send_csnp[1]);