Call mstsc in WSL

plugins/hosts/linux/cap/rdp.rb

@@ -12,9 +12,13 @@ module VagrantPlugins
               "xfreerdp"
             elsif Vagrant::Util::Which.which("rdesktop")
               "rdesktop"
+            else
+              if Vagrant::Util::Platform.wsl?
+                "mstsc.exe"
               else
                 raise Vagrant::Errors::LinuxRDPClientNotFound
               end
+            end
 
           args = []
 
@@ -30,6 +34,17 @@ module VagrantPlugins
             args << "-p" << rdp_info[:password] if rdp_info[:password]
             args += rdp_info[:extra_args] if rdp_info[:extra_args]
             args << "#{rdp_info[:host]}:#{rdp_info[:port]}"
+          when "mstsc.exe"
+            # Setup password
+            cmdKeyArgs = [
+              "/add:#{rdp_info[:host]}:#{rdp_info[:port]}",
+              "/user:#{rdp_info[:username]}",
+              "/pass:#{rdp_info[:password]}",
+            ]
+            Vagrant::Util::Subprocess.execute("cmdkey.exe", *cmdKeyArgs)
+
+            args = ["/v:#{rdp_info[:host]}:#{rdp_info[:port]}"]
+            args += rdp_info[:extra_args] if rdp_info[:extra_args]
           end
 
           # Finally, run the client.