Try a better way with MettleConfig

This will obviously affect stageless payloads, but that's okay, since
there's no stage! Thanks to @mkienow-r7 for the nudge. <3

lib/msf/base/sessions/mettle_config.rb

@@ -94,6 +94,16 @@ module Msf
         opts.slice(:uuid, :session_guid, :uri, :debug, :log_file, :name)
       end
 
+      # Stage encoding is not safe for Mettle (doesn't apply to stageless)
+      def encode_stage?
+        if datastore['EnableStageEncoding'] && !@warned
+          print_warning("Stage encoding is not currently supported for #{refname}")
+          @warned = true
+        end
+
+        false
+      end
+
     end
   end
 end

modules/payloads/stages/linux/aarch64/meterpreter.rb

@@ -115,14 +115,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('aarch64-linux-musl',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end

modules/payloads/stages/linux/armle/meterpreter.rb

@@ -84,14 +84,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('armv5l-linux-musleabi',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end

modules/payloads/stages/linux/mipsbe/meterpreter.rb

@@ -95,14 +95,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('mips-linux-muslsf',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end

modules/payloads/stages/linux/mipsle/meterpreter.rb

@@ -96,14 +96,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('mipsel-linux-muslsf',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end

modules/payloads/stages/linux/x64/meterpreter.rb

@@ -92,14 +92,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('x86_64-linux-musl',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end

modules/payloads/stages/linux/x86/meterpreter.rb

@@ -95,14 +95,4 @@ module MetasploitModule
     MetasploitPayloads::Mettle.new('i486-linux-musl',
       generate_config(opts.merge({scheme: 'tcp'}))).to_binary :process_image
   end
-
-  # Stage encoding is not safe for this payload
-  def encode_stage?
-    if datastore['EnableStageEncoding'] && !@warned
-      print_warning("Stage encoding is not currently supported for #{refname}")
-      @warned = true
-    end
-
-    false
-  end
 end