don't add key_id to legacy private encrypted slap xml

lib/diaspora_federation/salmon/encrypted_slap.rb

@@ -114,7 +114,7 @@ module DiasporaFederation
         EncryptedSlap.new.tap do |slap|
           slap.author_id = author_id
 
-          magic_envelope = MagicEnvelope.new(entity, author_id)
+          magic_envelope = MagicEnvelope.new(entity)
           slap.cipher_params = magic_envelope.encrypt!
           slap.magic_envelope_xml = magic_envelope.envelop(privkey)
         end

lib/diaspora_federation/salmon/magic_envelope.rb

@@ -49,8 +49,8 @@ module DiasporaFederation
       # @param [Entity] payload Entity instance
       # @param [String] sender diaspora-ID of the sender
       # @raise [ArgumentError] if either argument is not of the right type
-      def initialize(payload, sender)
-        raise ArgumentError unless payload.is_a?(Entity) && sender.is_a?(String)
+      def initialize(payload, sender=nil)
+        raise ArgumentError unless payload.is_a?(Entity)
 
         @payload = payload
         @sender = sender
@@ -69,7 +69,7 @@ module DiasporaFederation
             xml["me"].data(Base64.urlsafe_encode64(payload_data), type: DATA_TYPE)
             xml["me"].encoding(ENCODING)
             xml["me"].alg(ALGORITHM)
-            xml["me"].sig(Base64.urlsafe_encode64(sign(privkey)), key_id: Base64.urlsafe_encode64(sender))
+            xml["me"].sig(Base64.urlsafe_encode64(sign(privkey)), key_id)
           }
         }
       end
@@ -132,6 +132,10 @@ module DiasporaFederation
         @payload_data ||= XmlPayload.pack(@payload).to_xml.strip
       end
 
+      def key_id
+        sender ? {key_id: Base64.urlsafe_encode64(sender)} : {}
+      end
+
       # Builds the xml root node of the magic envelope.
       #
       # @yield [xml] Invokes the block with the

spec/lib/diaspora_federation/salmon/encrypted_slap_spec.rb

@@ -87,6 +87,11 @@ module DiasporaFederation
           expect(doc1.xpath("d:diaspora/me:env", ns).to_xml).to eq(doc2.xpath("d:diaspora/me:env", ns).to_xml)
         end
 
+        it "does not add the sender to the magic envelope" do
+          doc = Nokogiri::XML::Document.parse(slap_xml)
+          expect(doc.at_xpath("d:diaspora/me:env/me:sig", ns)["key_id"]).to be_nil
+        end
+
         context "header" do
           subject {
             doc = Nokogiri::XML::Document.parse(slap_xml)