Fixup railgun utils

Implement DsGetDcNamea to return current domain using example
railgun utils techniques.

lib/msf/core/post/windows/accounts.rb

@@ -5,6 +5,47 @@ module Windows
 
 module Accounts
 
+  GUID = [
+    ['Data1',:DWORD],
+    ['Data2',:WORD],
+    ['Data3',:WORD],
+    ['Data4','BYTE[8]']
+  ]
+
+  DOMAIN_CONTROLLER_INFO = [
+    ['DomainControllerName',:LPSTR],
+    ['DomainControllerAddress',:LPSTR],
+    ['DomainControllerAddressType',:ULONG],
+    ['DomainGuid',GUID],
+    ['DomainName',:LPSTR],
+    ['DnsForestName',:LPSTR],
+    ['Flags',:ULONG],
+    ['DcSiteName',:LPSTR],
+    ['ClientSiteName',:LPSTR]
+  ]
+
+  def get_domain(server_name=nil)
+    domain = nil
+    result = session.railgun.netapi32.DsGetDcNameA(
+      server_name,
+      nil,
+      nil,
+      nil,
+      0,
+      4)
+
+    begin
+      dc_info_addr = result['DomainControllerInfo']
+      dc_info = session.railgun.util.read_data(DOMAIN_CONTROLLER_INFO, dc_info_addr)
+      pointer = session.railgun.util.unpack_pointer(dc_info['DomainName'])
+      domain = session.railgun.util.read_string(pointer)
+    ensure
+      session.railgun.netapi32.NetApiBufferFree(dc_info_addr)
+    end
+
+    return domain
+  end
+
   ##
   # delete_user(username, server_name = nil)
   #

lib/msf/core/post/windows/ldap.rb

@@ -119,7 +119,7 @@ module LDAP
     bind_default_ldap_server(1) do |session_handle|
       print_status("Querying default naming context")
 
-      query_result = query_ldap(session_handle, "", 0, "(objectClass=computer)", ["defaultNamingContext"])
+      query_result = query_ldap(session_handle, "", 0, "(objectClass=*)", ["defaultNamingContext"])
       first_entry_fields = query_result[:results].first
       # Value from First Attribute of First Entry
       default_naming_context = first_entry_fields.first

lib/rex/post/meterpreter/extensions/stdapi/railgun/def/def_kernel32.rb

@@ -3668,11 +3668,11 @@ class Def_kernel32
     #	])
 
     dll.add_function( 'lstrlenA', 'DWORD',[
-      ["PCHAR","lpString","in"],
+      ["DWORD","lpString","in"],
       ])
 
     dll.add_function( 'lstrlenW', 'DWORD',[
-      ["PWCHAR","lpString","in"],
+      ["DWORD","lpString","in"],
       ])
 
 

lib/rex/post/meterpreter/extensions/stdapi/railgun/def/def_netapi32.rb

@@ -12,6 +12,19 @@ class Def_netapi32
   def self.create_dll(dll_path = 'netapi32')
     dll = DLL.new(dll_path, ApiConstants.manager)
 
+    dll.add_function('NetApiBufferFree','DWORD',[
+      ["LPVOID","Buffer","in"]
+    ])
+
+    dll.add_function('DsGetDcNameA', 'DWORD',[
+      ["PWCHAR","ComputerName","in"],
+      ["PWCHAR","DomainName","in"],
+      ["PBLOB","DomainGuid","in"],
+      ["PWCHAR","SiteName","in"],
+      ["DWORD","Flags","in"],
+      ["PDWORD","DomainControllerInfo","out"]
+    ])
+
     dll.add_function('NetUserDel', 'DWORD',[
       ["PWCHAR","servername","in"],
       ["PWCHAR","username","in"],

lib/rex/post/meterpreter/extensions/stdapi/railgun/util.rb

@@ -375,6 +375,19 @@ class  Util
     return str
   end
 
+  def read_string(pointer, length=nil)
+    if is_null_pointer(pointer)
+      return ''
+    end
+
+    unless length
+      length = railgun.kernel32.lstrlenA(pointer)['return']
+    end
+
+    chars = read_array(:CHAR, length, pointer)
+    return chars.join('')
+  end
+
   #
   # Read a given number of bytes from memory or from a provided buffer.
   #
@@ -513,10 +526,13 @@ class  Util
       return pointer_size
     end
 
+    if type.class == String
       if is_array_type?(type)
         element_type, length = split_array_type(type)
-
         return length * sizeof_type(element_type)
+      else
+        return sizeof_type(type.to_sym)
+      end
     end
 
     if is_struct_type?(type)
@@ -559,10 +575,8 @@ class  Util
   def struct_offsets(definition, offset)
     padding = 0
     offsets = []
-
     definition.each do |mapping|
       key, data_type = mapping
-
       if sizeof_type(data_type) > padding
         offset = offset + padding
       end
@@ -570,7 +584,6 @@ class  Util
       offsets.push(offset)
 
       offset = offset + sizeof_type(data_type)
-
       padding = calc_padding(offset)
     end
 
@@ -606,12 +619,11 @@ class  Util
     if type =~ /^(\w+)\[(\w+)\]$/
       element_type = $1
       length = $2
-
       unless length =~ /^\d+$/
         length = railgun.const(length)
       end
 
-      return element_type, length
+      return element_type.to_sym, length.to_i
     else
       raise "Can not split non-array type #{type}"
     end