tighten up corner cases with option validation

Author: busterb

lib/msf/core/opt_base.rb

@@ -36,14 +36,14 @@ def initialize(in_name, attrs = [],
         self.required = required
         self.desc     = attrs.is_a?(String) ? attrs : desc
         self.enums    = [ *(enums) ].map { |x| x.to_s }
-        if default.nil? && enums.length > 0
-          self.default  = enums[0]
-        else
-          self.default = default
-        end
+        self.default  = default
         regex_temp    = regex
       else
-        self.required = attrs[0] || required
+        if attrs[0].nil?
+          self.required = required
+        else
+          self.required = attrs[0]
+        end
         self.desc     = attrs[1] || desc
         self.default  = attrs[2] || default
         self.enums    = attrs[3] || enums

lib/msf/core/opt_bool.rb

@@ -18,6 +18,8 @@ def type
 
     def valid?(value, check_empty: true)
       return false if check_empty && empty_required_value?(value)
+      return true if value.nil? && !required?
+
       !(value.nil? ||
         value.to_s.empty? ||
         value.to_s.match(ANY_REGEX).nil?)

lib/msf/core/opt_enum.rb

@@ -21,7 +21,7 @@ def valid?(value = self.value, check_empty: true)
       return false if check_empty && empty_required_value?(value)
       return true if value.nil? && !required?
 
-      (value && enums.include?(value.to_s))
+      !value.nil? && enums.include?(value.to_s)
     end
 
     def normalize(value = self.value)