utils: fix #16138 by checking if vhosts flag is set (#16141)

* utils: fix #16138 by checking if vhosts flag is set

* utils,node: fix defaults for rpcvhosts

* node,utils: address review concerns

cmd/utils/flags.go

@@ -400,7 +400,7 @@ var (
 	RPCVirtualHostsFlag = cli.StringFlag{
 		Name:  "rpcvhosts",
 		Usage: "Comma separated list of virtual hostnames from which to accept requests (server enforced). Accepts '*' wildcard.",
-		Value: "localhost",
+		Value: strings.Join(node.DefaultConfig.HTTPVirtualHosts, ","),
 	}
 	RPCApiFlag = cli.StringFlag{
 		Name:  "rpcapi",
@@ -695,9 +695,10 @@ func setHTTP(ctx *cli.Context, cfg *node.Config) {
 	if ctx.GlobalIsSet(RPCApiFlag.Name) {
 		cfg.HTTPModules = splitAndTrim(ctx.GlobalString(RPCApiFlag.Name))
 	}
-
+	if ctx.GlobalIsSet(RPCVirtualHostsFlag.Name) {
 		cfg.HTTPVirtualHosts = splitAndTrim(ctx.GlobalString(RPCVirtualHostsFlag.Name))
 	}
+}
 
 // setWS creates the WebSocket RPC listener interface string from the set
 // command line flags, returning empty if the HTTP endpoint is disabled.

node/defaults.go

@@ -38,6 +38,7 @@ var DefaultConfig = Config{
 	DataDir:          DefaultDataDir(),
 	HTTPPort:         DefaultHTTPPort,
 	HTTPModules:      []string{"net", "web3"},
+	HTTPVirtualHosts: []string{"localhost"},
 	WSPort:           DefaultWSPort,
 	WSModules:        []string{"net", "web3"},
 	P2P: p2p.Config{