Fix missing #add_static API method

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

@@ -52,11 +52,17 @@ def add_static_hosts(entries = datastore['STATIC_ENTRIES'], type = 'A')
       data = entries.split(';')
     end
     data.each do |entry|
-      next if entry.gsub(/\s/,'').empty?
-      addr, names = entry.split(' ', 2)
+      next if entry.gsub(/\s/, '').empty?
+
+      address, names = entry.split(' ', 2)
       names.split.each do |name|
-        name << '.' unless name[-1] == '.' or name == '*'
-        service.cache.add_static(name, addr, type)
+        name << '.' unless name.end_with?('.') || name == '*'
+
+        unless Rex::Socket.is_ip_addr?(address.to_s) && (name.to_s.match(MATCH_HOSTNAME) || name == '*')
+          raise "Invalid parameters for static entry - #{name}, #{address}, #{type}"
+        end
+
+        service.cache.cache_record(Dnsruby::RR.create(name: name, type: type, address: address), expire: false)
       end
     end
     service.cache.records.select {|r,e| e == 0}

lib/rex/proto/dns/cache.rb

@@ -45,15 +45,22 @@ def find(search, type = Dnsruby::Types::A)
     # Add record to cache, only when "running"
     #
     # @param record [Dnsruby::RR] Record to cache
-    def cache_record(record)
+    def cache_record(record, expire: true)
       return unless @monitor_thread
-      if record.is_a?(Dnsruby::RR) and
-      (!record.respond_to?(:address) or Rex::Socket.is_ip_addr?(record.address.to_s)) and
-      record.name.to_s.match(MATCH_HOSTNAME)
-        add(record, ::Time.now.to_i + record.ttl)
-      else
-        raise "Invalid record for cache entry - #{record.inspect}"
+
+      unless record.is_a?(Dnsruby::RR)
+        raise "Invalid record for cache entry (not an RR) - #{record.inspect}"
+      end
+
+      unless (!record.respond_to?(:address) || Rex::Socket.is_ip_addr?(record.address.to_s))
+        raise "Invalid record for cache entry (no IP address) - #{record.inspect}"
       end
+
+      unless record.name.to_s.match(MATCH_HOSTNAME)
+        raise "Invalid record for cache entry (invalid hostname) - #{record.inspect}"
+      end
+
+      add(record, expire ? (::Time.now.to_i + record.ttl) : 0)
     end
 
     #