Keep other instances of via_string to the same convention

lib/msf/core/exploit/remote/dns/server.rb

@@ -102,7 +102,7 @@ module Server
   def start_service
     begin
 
-      comm = _determine_server_comm
+      comm = _determine_server_comm(datastore['SRVHOST'])
       self.service = Rex::ServiceManager.start(
         Rex::Proto::DNS::Server,
         datastore['SRVHOST'],

lib/msf/core/exploit/remote/socket_server.rb

@@ -148,7 +148,7 @@ protected
   #
   # Determines appropriate listener comm
   #
-  def _determine_server_comm(srv_comm = datastore['ListenerComm'].to_s)
+  def _determine_server_comm(ip, srv_comm = datastore['ListenerComm'].to_s)
     case srv_comm
     when 'local'
       comm = ::Rex::Socket::Comm::Local
@@ -157,7 +157,7 @@ protected
       raise(RuntimeError, "Socket Server Comm (Session #{srv_comm}) does not exist") unless comm
       raise(RuntimeError, "Socket Server Comm (Session #{srv_comm}) does not implement Rex::Socket::Comm") unless comm.is_a? ::Rex::Socket::Comm
     when nil, ''
-      comm = nil
+      comm = Rex::Socket::SwitchBoard.best_comm(ip)
     else
       raise(RuntimeError, "SocketServer Comm '#{srv_comm}' is invalid")
     end
@@ -165,13 +165,9 @@ protected
     comm
   end
 
-  def via_string_for_ip(ip, comm)
-    comm_used = comm
-    comm_used ||= Rex::Socket::SwitchBoard.best_comm(ip)
-    comm_used ||= Rex::Socket::Comm::Local
-
-    if comm_used.respond_to?(:type) && comm_used.respond_to?(:sid)
-      via = "via the #{comm_used.type} on session #{comm_used.sid}"
+  def via_string(comm)
+    if comm.respond_to?(:type) && comm.respond_to?(:sid)
+      via = "via the #{comm.type} on session #{comm.sid}"
     else
       via = ""
     end

lib/msf/core/exploit/remote/tcp_server.rb

@@ -57,7 +57,7 @@ module Exploit::Remote::TcpServer
   def start_service(*args)
     begin
 
-      comm = _determine_server_comm
+      comm = _determine_server_comm(srvhost)
 
       self.service = Rex::Socket::TcpServer.create(
         'LocalHost'      => srvhost,
@@ -106,7 +106,7 @@ module Exploit::Remote::TcpServer
       raise e
     end
 
-    via = via_string_for_ip(srvhost, comm)
+    via = via_string(comm)
     hoststr = Rex::Socket.is_ipv6?(srvhost) ? "[#{srvhost}]" : srvhost
     print_status("Started service listener on #{hoststr}:#{srvport} #{via}")
   end