CA-113824: Prevent "xenapi" prefixed bridge monitoring

This patch also refactors the code for getting the prefix interfaces
that we do not want to be monitored. It now gets the list of prefixes
from xcp-networkd-conf file.
Also, it adds an example config file.

Signed-off-by: Ravi Pandey <[email protected]>

Author: ravippandey

networkd/network_monitor_thread.ml

@@ -25,6 +25,14 @@ open D
 (** Table for bonds status. *)
 let bonds_status : (string, (int * int)) Hashtbl.t = Hashtbl.create 10
 
+let monitor_blacklist = ref [
+	"dummy";
+	"xenbr";
+	"xapi";
+	"ovs-system";
+	"xenapi";
+]
+
 let xapi_rpc request =
 	Rpc_client.do_rpc_unix
 		~content_type:(Rpc_client.content_type_of_string "text/xml")
@@ -98,8 +106,17 @@ let get_link_stats () =
 
 	let cache = Link.cache_alloc s in
 	let links = Link.cache_to_list cache in
-	let devs = List.map (fun link ->
-		let name = standardise_name (Link.get_name link) in
+	let links =
+		List.map (fun link ->
+			(standardise_name (Link.get_name link)), link
+		) links |>
+		List.filter (fun (name,link) ->
+			let is_monitor_blacklisted = List.exists (fun s -> String.startswith s name) !monitor_blacklist ||
+						(String.startswith "eth" name && String.contains name '.') in
+			not is_monitor_blacklisted
+		) in
+
+	let devs = List.map (fun (name,link) ->
 		let convert x = Int64.of_int (Unsigned.UInt64.to_int x) in
 		let eth_stat = {default_stats with
 			rx_bytes = Link.get_stat link Link.RX_BYTES |> convert;
@@ -111,13 +128,6 @@ let get_link_stats () =
 		} in
 		name, eth_stat
 	) links in
-	let devs = List.filter (fun (name, _) ->
-		not(String.startswith "dummy" name) &&
-			not(String.startswith "xenbr" name) &&
-			not(String.startswith "xapi" name) &&
-			not(String.startswith "eth" name && String.contains name '.') &&
-			name <> "ovs-system"
-	) devs in
 
 	Cache.free cache;
 	Socket.close s;

networkd/networkd.ml

@@ -15,6 +15,7 @@
 open Pervasiveext
 open Fun
 open Network_utils
+open Xstringext
 
 module D = Debug.Make(struct let name = "networkd" end)
 open D
@@ -42,6 +43,10 @@ let resources = [
   }
 ]
 
+let options = [
+	"monitor_blacklist", Arg.String (fun x -> Network_monitor_thread.monitor_blacklist := String.split ',' x), (fun () -> String.concat "," !Network_monitor_thread.monitor_blacklist), "List of prefixes of interface names that are not to be monitored";
+]
+
 let start server =
 	Network_monitor_thread.start ();
 	Network_server.on_startup ();
@@ -70,7 +75,7 @@ let _ =
 	begin match Xcp_service.configure2
 		~name:Sys.argv.(0)
 		~version:Version.version
-		~doc ~resources () with
+		~doc ~options ~resources () with
 	| `Ok () -> ()
 	| `Error m ->
 		Printf.fprintf stderr "%s\n" m;

xcp-networkd.conf

@@ -0,0 +1,20 @@
+# Configuration file for xcp-networkd
+
+# Default paths to search for binaries
+# search-path=
+
+# The location of the inventory file
+#inventory = /etc/xensource-inventory
+
+# True to use the message switch; false for direct Unix domain socket
+# comms
+#use-switch = false
+
+#The location of brctl tool
+#brctl=/usr/sbin/brctl
+
+# The location for network config file in host
+#network-conf=/etc/xensource/network.conf
+
+#The list of prefix interfaces that are not to be monitored
+#monitor-blacklist=dummy,xenbr,xapi,ovs-system,xenapi