Add Tight VNC auth type

scripts/vnc-info.nse

@@ -1,5 +1,6 @@
 local shortport = require "shortport"
 local stdnse = require "stdnse"
+local string = require "string"
 local vnc = require "vnc"
 
 description = [[
@@ -88,6 +89,48 @@ action = function(host, port)
     v:disconnect()
   end
 
+  if v:supportsSecType(v.sectypes.TIGHT) then
+    if not v.socket:get_info() then
+      -- reconnect if necessary
+      v:connect()
+      v:handshake()
+    end
+    status, data = v:handshake_tight()
+    if not status then
+      stdnse.debug1("Failed to handshake Tight: %s", data)
+    else
+      local mt = {
+        __tostring = function(t)
+          return string.format("%s %s (%d)", t.vendor, t.signature, t.code)
+        end
+      }
+      local tunnels = {}
+      for _, t in ipairs(v.tight.tunnels) do
+        setmetatable(t, mt)
+        tunnels[#tunnels+1] = t
+      end
+      if #tunnels > 0 then
+        result["Tight auth tunnels"] = tunnels
+      end
+      if #v.tight.types == 0 then
+        none_auth = true
+        result["Tight auth subtypes"] = {"None"}
+      else
+        local subtypes = {}
+        for _, t in ipairs(v.tight.types) do
+          if t.code == 1 then
+            none_auth = true
+          end
+          setmetatable(t, mt)
+          subtypes[#subtypes+1] = t
+        end
+        result["Tight auth subtypes"] = subtypes
+      end
+    end
+    -- Reset the connection for further tests
+    v:disconnect()
+  end
+
   if v:supportsSecType(v.sectypes.TLS) then
     if not v.socket:get_info() then
       -- reconnect if necessary