From 9b1ed1e7e16a8f55a5bd7b7ce72195a08ca2968d Mon Sep 17 00:00:00 2001
From: wadabum <23560633+wadabum@users.noreply.github.com>
Date: Mon, 13 Mar 2023 12:41:51 +0100
Subject: [PATCH] Log access CRAM-MD5 authentication failures  (#2304)

see https://github.com/postalserver/postal/issues/1182#issuecomment-1360832523
---
 lib/postal/smtp_server/client.rb | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/postal/smtp_server/client.rb b/lib/postal/smtp_server/client.rb
index be9f074..916bd5b 100644
--- a/lib/postal/smtp_server/client.rb
+++ b/lib/postal/smtp_server/client.rb
@@ -228,7 +228,10 @@ module Postal
           username, password = Base64.decode64(data).split(' ', 2).map{ |a| a.chomp }
           org_permlink, server_permalink = username.split(/[\/\_]/, 2)
           server = ::Server.includes(:organization).where(:organizations => {:permalink => org_permlink}, :permalink => server_permalink).first
-          next '535 Denied' if server.nil?
+          if server.nil?
+            log "\e[33m WARN: AUTH failure for #{@ip_address}\e[0m"
+            next '535 Denied'
+          end
           grant = nil
           server.credentials.where(:type => 'SMTP').each do |credential|
             correct_response = OpenSSL::HMAC.hexdigest(CRAM_MD5_DIGEST, credential.key, challenge)
@@ -239,7 +242,11 @@ module Postal
               break
             end
           end
-          grant || '535 Denied'
+          if grant.nil?
+            log "\e[33m WARN: AUTH failure for #{@ip_address}\e[0m"
+            next "535 Denied"
+          end
+          grant
         end
 
         @proc = handler