Merge branch '37359-cablett-support-envelope-to' into 'master'

Accept Envelope-To header

Closes #37359

See merge request gitlab-org/gitlab!22354

changelogs/unreleased/37359-cablett-support-envelope-to.yml

+---
+title: Accept `Envelope-To` as possible location for Service Desk key
+merge_request: 22354
+author: Max Winterstein
+type: added

lib/gitlab/email/receiver.rb

@@ -66,7 +66,8 @@ module Gitlab
 
       def key_from_additional_headers(mail)
         find_key_from_references(mail) ||
-          find_key_from_delivered_to_header(mail)
+          find_key_from_delivered_to_header(mail) ||
+          find_key_from_envelope_to_header(mail)
       end
 
       def ensure_references_array(references)
@@ -96,6 +97,13 @@ module Gitlab
         end
       end
 
+      def find_key_from_envelope_to_header(mail)
+        Array(mail[:envelope_to]).find do |header|
+          key = Gitlab::IncomingEmail.key_from_address(header.value)
+          break key if key
+        end
+      end
+
       def ignore_auto_reply!(mail)
         if auto_submitted?(mail) || auto_replied?(mail)
           raise AutoGeneratedEmailError

spec/fixtures/emails/envelope_to_header.eml

+Return-Path: <jake@example.com>
+Received: from myserver.example.com ([unix socket]) by myserver (Cyrus v2.2.13-Debian-2.2.13-19+squeeze3) with LMTPA; Thu, 13 Jun 2013 17:03:50 -0400
+Received: from mail.example.com (mail.example.com [IPv6:2607:f8b0:4001:c03::234]) by myserver.example.com (8.14.3/8.14.3/Debian-9.4) with ESMTP id r5DL3nFJ016967 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for <incoming+gitlabhq/gitlabhq@example.com>; Thu, 13 Jun 2013 17:03:50 -0400
+Received: by myserver.example.com with SMTP id f4so21977375iea.25 for <incoming+gitlabhq/gitlabhq@appmail.example.com>; Thu, 13 Jun 2013 14:03:48 -0700
+Received: by 10.0.0.1 with HTTP; Thu, 13 Jun 2013 14:03:48 -0700
+From: "jake@example.com" <jake@example.com>
+To: "support@example.com" <support@example.com>
+Subject: Insert hilarious subject line here
+Date: Tue, 26 Nov 2019 14:22:41 +0000
+Message-ID: <7e2296f83dbf4de388cbf5f56f52c11f@EXDAG29-1.EXCHANGE.INT>
+Accept-Language: de-DE, en-US
+Content-Language: de-DE
+X-MS-Has-Attach:
+X-MS-TNEF-Correlator:
+x-ms-exchange-transport-fromentityheader: Hosted
+x-originating-ip: [62.96.54.178]
+Content-Type: multipart/alternative;
+	boundary="_000_7e2296f83dbf4de388cbf5f56f52c11fEXDAG291EXCHANGEINT_"
+MIME-Version: 1.0
+Envelope-To: incoming+gitlabhq/gitlabhq+auth_token@appmail.example.com
+
+--_000_7e2296f83dbf4de388cbf5f56f52c11fEXDAG291EXCHANGEINT_
+Content-Type: text/plain; charset="iso-8859-1"
+Content-Transfer-Encoding: quoted-printable
+
+
+
+--_000_7e2296f83dbf4de388cbf5f56f52c11fEXDAG291EXCHANGEINT_
+Content-Type: text/html; charset="iso-8859-1"
+Content-Transfer-Encoding: quoted-printable
+
+Look, a message with some alternate headers! We should really support them.

spec/fixtures/emails/forwarded_new_issue.eml

-Delivered-To: incoming+gitlabhq/gitlabhq+auth_token@appmail.adventuretime.ooo
-Return-Path: <jake@adventuretime.ooo>
-Received: from iceking.adventuretime.ooo ([unix socket]) by iceking (Cyrus v2.2.13-Debian-2.2.13-19+squeeze3) with LMTPA; Thu, 13 Jun 2013 17:03:50 -0400
-Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) by iceking.adventuretime.ooo (8.14.3/8.14.3/Debian-9.4) with ESMTP id r5DL3nFJ016967 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for <incoming+gitlabhq/gitlabhq@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 17:03:50 -0400
-Received: by mail-ie0-f180.google.com with SMTP id f4so21977375iea.25 for <incoming+gitlabhq/gitlabhq@appmail.adventuretime.ooo>; Thu, 13 Jun 2013 14:03:48 -0700
+Delivered-To: incoming+gitlabhq/gitlabhq+auth_token@appmail.example.com
+Return-Path: <jake@example.com>
+Received: from iceking.example.com ([unix socket]) by iceking (Cyrus v2.2.13-Debian-2.2.13-19+squeeze3) with LMTPA; Thu, 13 Jun 2013 17:03:50 -0400
+Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) by iceking.example.com (8.14.3/8.14.3/Debian-9.4) with ESMTP id r5DL3nFJ016967 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for <incoming+gitlabhq/gitlabhq@appmail.example.com>; Thu, 13 Jun 2013 17:03:50 -0400
+Received: by mail-ie0-f180.google.com with SMTP id f4so21977375iea.25 for <incoming+gitlabhq/gitlabhq@appmail.example.com>; Thu, 13 Jun 2013 14:03:48 -0700
 Received: by 10.0.0.1 with HTTP; Thu, 13 Jun 2013 14:03:48 -0700
 Date: Thu, 13 Jun 2013 17:03:48 -0400
-From: Jake the Dog <jake@adventuretime.ooo>
-Delivered-To: support@adventuretime.ooo
-To: support@adventuretime.ooo
+From: Jake the Dog <jake@example.com>
+Delivered-To: support@example.com
+To: support@example.com
 Message-ID: <CADkmRc+rNGAGGbV2iE5p918UVy4UyJqVcXRO2=otppgzduJSg@mail.gmail.com>
 Subject: New Issue by email
 Mime-Version: 1.0

spec/lib/gitlab/email/receiver_spec.rb

@@ -5,22 +5,27 @@ require 'spec_helper'
 describe Gitlab::Email::Receiver do
   include_context :email_shared_context
 
-  context "when the email contains a valid email address in a Delivered-To header" do
-    let(:email_raw) { fixture_file('emails/forwarded_new_issue.eml') }
+  context 'when the email contains a valid email address in a header' do
     let(:handler) { double(:handler) }
 
     before do
-      stub_incoming_email_setting(enabled: true, address: "incoming+%{key}@appmail.adventuretime.ooo")
-
       allow(handler).to receive(:execute)
       allow(handler).to receive(:metrics_params)
       allow(handler).to receive(:metrics_event)
+
+      stub_incoming_email_setting(enabled: true, address: "incoming+%{key}@appmail.example.com")
+    end
+
+    context 'when in a Delivered-To header' do
+      let(:email_raw) { fixture_file('emails/forwarded_new_issue.eml') }
+
+      it_behaves_like 'correctly finds the mail key'
     end
 
-    it "finds the mail key" do
-      expect(Gitlab::Email::Handler).to receive(:for).with(an_instance_of(Mail::Message), 'gitlabhq/gitlabhq+auth_token').and_return(handler)
+    context 'when in an Envelope-To header' do
+      let(:email_raw) { fixture_file('emails/envelope_to_header.eml') }
 
-      receiver.execute
+      it_behaves_like 'correctly finds the mail key'
     end
   end
 

spec/support/shared_examples/email_shared_examples.rb

+# frozen_string_literal: true
+
+shared_examples_for 'correctly finds the mail key' do
+  specify do
+    expect(Gitlab::Email::Handler).to receive(:for).with(an_instance_of(Mail::Message), 'gitlabhq/gitlabhq+auth_token').and_return(handler)
+
+    receiver.execute
+  end
+end