zebra: Adding zapi client close notification

When zebra detects a client close, send a zapi client close
notification.

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

6 files changed, 74 insertions, 1 deletions

diff --git a/lib/log.c b/lib/log.c
index 7b37ba7f27..03ed23a04b 100644
--- a/lib/log.c
+++ b/lib/log.c
@@ -456,7 +456,8 @@ static const struct zebra_desc_table command_types[] = {
 	DESC_ENTRY(ZEBRA_NHG_ADD),
 	DESC_ENTRY(ZEBRA_NHG_DEL),
 	DESC_ENTRY(ZEBRA_NHG_NOTIFY_OWNER),
-	DESC_ENTRY(ZEBRA_ROUTE_NOTIFY_REQUEST)};
+	DESC_ENTRY(ZEBRA_ROUTE_NOTIFY_REQUEST),
+	DESC_ENTRY(ZEBRA_CLIENT_CLOSE_NOTIFY)};
 #undef DESC_ENTRY
 
 static const struct zebra_desc_table unknown = {0, "unknown", '?'};
diff --git a/lib/zclient.c b/lib/zclient.c
index 053014f86d..ba94b7fb99 100644
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -3528,6 +3528,23 @@ stream_failure:
 	return -1;
 }
 
+/* Utility to decode client close notify info */
+int zapi_client_close_notify_decode(struct stream *s,
+				    struct zapi_client_close_info *info)
+{
+	memset(info, 0, sizeof(*info));
+
+	STREAM_GETC(s, info->proto);
+	STREAM_GETW(s, info->instance);
+	STREAM_GETL(s, info->session_id);
+
+	return 0;
+
+stream_failure:
+
+	return -1;
+}
+
 /* Zebra client message read function. */
 static int zclient_read(struct thread *thread)
 {
@@ -3868,6 +3885,12 @@ static int zclient_read(struct thread *thread)
 		if (zclient->sr_policy_notify_status)
 			(*zclient->sr_policy_notify_status)(command, zclient,
 							    length, vrf_id);
+		break;
+	case ZEBRA_CLIENT_CLOSE_NOTIFY:
+		if (zclient->zebra_client_close_notify)
+			(*zclient->zebra_client_close_notify)(command, zclient,
+							      length, vrf_id);
+		break;
 	default:
 		break;
 	}
diff --git a/lib/zclient.h b/lib/zclient.h
index ae94237b76..33c1e732ee 100644
--- a/lib/zclient.h
+++ b/lib/zclient.h
@@ -220,6 +220,7 @@ typedef enum {
 	ZEBRA_OPAQUE_UNREGISTER,
 	ZEBRA_NEIGH_DISCOVER,
 	ZEBRA_ROUTE_NOTIFY_REQUEST,
+	ZEBRA_CLIENT_CLOSE_NOTIFY,
 } zebra_message_types_t;
 
 enum zebra_error_types {
@@ -377,6 +378,7 @@ struct zclient {
 	int (*opaque_register_handler)(ZAPI_CALLBACK_ARGS);
 	int (*opaque_unregister_handler)(ZAPI_CALLBACK_ARGS);
 	int (*sr_policy_notify_status)(ZAPI_CALLBACK_ARGS);
+	int (*zebra_client_close_notify)(ZAPI_CALLBACK_ARGS);
 };
 
 /* Zebra API message flag. */
@@ -1097,6 +1099,17 @@ zclient_send_neigh_discovery_req(struct zclient *zclient,
 				 const struct interface *ifp,
 				 const struct prefix *p);
 
+struct zapi_client_close_info {
+	/* Client session tuple */
+	uint8_t proto;
+	uint16_t instance;
+	uint32_t session_id;
+};
+
+/* Decode incoming client close notify */
+extern int zapi_client_close_notify_decode(struct stream *s,
+					   struct zapi_client_close_info *info);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index f7c123231e..c6210d14ac 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -2522,6 +2522,22 @@ int zsend_sr_policy_notify_status(uint32_t color, struct ipaddr *endpoint,
 	return zserv_send_message(client, s);
 }
 
+/* Send client close notify to client */
+int zsend_client_close_notify(struct zserv *client, struct zserv *closed_client)
+{
+	struct stream *s = stream_new(ZEBRA_MAX_PACKET_SIZ);
+
+	zclient_create_header(s, ZEBRA_CLIENT_CLOSE_NOTIFY, VRF_DEFAULT);
+
+	stream_putc(s, closed_client->proto);
+	stream_putw(s, closed_client->instance);
+	stream_putl(s, closed_client->session_id);
+
+	stream_putw_at(s, 0, stream_get_endp(s));
+
+	return zserv_send_message(client, s);
+}
+
 /* Send response to a table manager connect request to client */
 static void zread_table_manager_connect(struct zserv *client,
 					struct stream *msg, vrf_id_t vrf_id)
diff --git a/zebra/zapi_msg.h b/zebra/zapi_msg.h
index efc52059b6..9822d72022 100644
--- a/zebra/zapi_msg.h
+++ b/zebra/zapi_msg.h
@@ -105,6 +105,9 @@ extern int zsend_sr_policy_notify_status(uint32_t color,
 					 struct ipaddr *endpoint, char *name,
 					 int status);
 
+extern int zsend_client_close_notify(struct zserv *client,
+				     struct zserv *closed_client);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/zebra/zserv.c b/zebra/zserv.c
index 4b5791530d..c7b9433257 100644
--- a/zebra/zserv.c
+++ b/zebra/zserv.c
@@ -1300,6 +1300,21 @@ DEFUN (show_zebra_client_summary,
 	return CMD_SUCCESS;
 }
 
+static int zserv_client_close_cb(struct zserv *closed_client)
+{
+	struct listnode *node, *nnode;
+	struct zserv *client = NULL;
+
+	for (ALL_LIST_ELEMENTS(zrouter.client_list, node, nnode, client)) {
+		if (client->proto == closed_client->proto)
+			continue;
+
+		zsend_client_close_notify(client, closed_client);
+	}
+
+	return 0;
+}
+
 void zserv_init(void)
 {
 	/* Client list init. */
@@ -1312,4 +1327,6 @@ void zserv_init(void)
 
 	install_element(ENABLE_NODE, &show_zebra_client_cmd);
 	install_element(ENABLE_NODE, &show_zebra_client_summary_cmd);
+
+	hook_register(zserv_client_close, zserv_client_close_cb);
 }