Use railgun helper functions

Author: Meatballs1

lib/msf/core/exploit/local/windows_kernel.rb

@@ -48,23 +48,23 @@ def find_haldispatchtable
   # @return [nil] If the name specified could not be found.
   #
   def find_sys_base(drvname)
-    if sysinfo['Architecture'] =~ /(x86|wow64)/i
-      ptr_size = 4
+    if session.railgun.util.pointer_size == 8
+      ptr = '<Q'
     else
-      ptr_size = 8
+      ptr = 'V'
     end
 
-    results = session.railgun.psapi.EnumDeviceDrivers(0, 0, ptr_size)
+    results = session.railgun.psapi.EnumDeviceDrivers(0, 0, session.railgun.util.pointer_size)
     unless results['return']
       print_error("EnumDeviceDrivers failed (error: #{results['GetLastError']} #{results['ErrorMessage']})")
       return nil
     end
-    results = session.railgun.psapi.EnumDeviceDrivers(results['lpcbNeeded'], results['lpcbNeeded'], ptr_size)
+    results = session.railgun.psapi.EnumDeviceDrivers(results['lpcbNeeded'], results['lpcbNeeded'], session.railgun.util.pointer_size)
     unless results['return']
       print_error("EnumDeviceDrivers failed (error: #{results['GetLastError']} #{results['ErrorMessage']})")
       return nil
     end
-    addresses = results['lpImageBase'][0..results['lpcbNeeded'] - 1].unpack((ptr_size == 4 ? 'V' : 'Q') + '*')
+    addresses = results['lpImageBase'][0..results['lpcbNeeded'] - 1].unpack("#{ptr}*")
 
     addresses.each do |address|
       results = session.railgun.psapi.GetDeviceDriverBaseNameA(address, 48, 48)