Implement #290 (Sisimai::Rhost Improvement)

lib/sisimai/fact.rb

@@ -386,6 +386,7 @@ def self.rise(**argvs)
           o['reason'] = '' if o['reason'].start_with?('onhold', 'undefined')
           re = ''; de = o['destination']
           re = Sisimai::Rhost.get(o) if Sisimai::Rhost.match(o['rhost'])
+
           if re.empty?
             # Failed to detect a bounce reason by the value of "rhost"
             re = Sisimai::Rhost.get(o, de) if Sisimai::Rhost.match(de)

lib/sisimai/rhost.rb

@@ -46,6 +46,7 @@ def get(argvs, proxy = nil)
         remotehost = proxy || argvs['rhost'].downcase
         rhostclass = ''
         modulename = ''
+        return '' if argvs['diagnosticcode'].empty?
 
         RhostClass.each_key do |e|
           # Try to match with each key of RhostClass
@@ -54,7 +55,7 @@ def get(argvs, proxy = nil)
           rhostclass = 'sisimai/rhost/' << e.downcase
           break
         end
-        return nil if rhostclass.empty?
+        return '' if rhostclass.empty?
 
         require rhostclass
         reasontext = Module.const_get(modulename).get(argvs)

lib/sisimai/rhost/apple.rb

@@ -68,9 +68,8 @@ class << self
         # @see      https://support.apple.com/en-us/102322
         #           https://www.postmastery.com/icloud-postmastery-page/
         #           https://smtpfieldmanual.com/provider/apple
+        # @since v5.0.4
         def get(argvs)
-          return argvs['reason'] unless argvs['reason'].empty?
-
           issuedcode = argvs['diagnosticcode'].downcase
           reasontext = ''
 

lib/sisimai/rhost/cox.rb

@@ -6,16 +6,54 @@
     module Cox
       class << self
         ErrorCodes = {
-          # https://www.cox.com/residential/support/email-error-codes.html
-          'CXBL'      => 'blocked',       # The sending IP address has been blocked by Cox due to exhibiting spam-like behavior.
+          # CXBL
+          # - The sending IP address has been blocked by Cox due to exhibiting spam-like behavior.
+          # - Send an email request to Cox to ask for a sending IP address be unblocked.
+          #   Note: Cox has sole discretion whether to unblock the sending IP address.
+          'CXBL' => 'blocked',
+
+          # CXDNS
+          # - There was an issue with the connecting IP address Domain Name System (DNS).
+          # - The Reverse DNS (rDNS) lookup for your IP address is failing. 
+          #   - Confirm the IP address that sends your email.
+          #   - Check the rDNS of that IP address. If it passes, then wait 24 hours and try resending
+          #     your email.
+          'CXDNS' => 'requireptr',
+
+          # CXSNDR
+          # - There was a problem with the sender's domain.
+          # - Your email failed authentication checks against your sending domain's SPF, DomainKeys,
+          #   or DKIM policy.
+          'CXSNDR' => 'authfailure',
+
+          # CXSMTP
+          # - There was a violation of SMTP protocol.
+          # - Your email wasn't delivered because Cox was unable to verify that it came from a
+          #   legitimate email sender.
+          'CXSMTP' => 'rejected',
+
+          # CXCNCT
+          # - There was a connection issue from the IP address.
+          # - There is a limit to the number of concurrent SMTP connections per IP address to
+          #   protect the systems against attack. Ensure that the sending email server is not
+          #   opening more than 10 concurrent connections to avoid reaching this limit.
+          'CXCNCT' => 'toomanyconn',
+
+          # CXMXRT
+          #   - The sender has sent email to too many recipients and needs to wait before sending
+          #     more email.
+          #   - The email sender has exceeded the maximum number of sent email allowed.
+          'CXMXRT' => 'toomanyconn', 
+
+          # CDRBL
+          # - The sending IP address has been temporarily blocked by Cox due to exhibiting spam-like
+          #   behavior.
+          # - The block duration varies depending on reputation and other factors, but will not exceed
+          #   24 hours. Inspect email traffic for potential spam, and retry email delivery.
+          'CDRBL' => 'blocked',
+
           'CXTHRT'    => 'securityerror', # Email sending limited due to suspicious account activity.
           'CXMJ'      => 'securityerror', # Email sending blocked due to suspicious account activity on primary Cox account.
-          'CXDNS'     => 'blocked',       # There was an issue with the connecting IP address Domain Name System (DNS).
-          'CXSNDR'    => 'rejected',      # There was a problem with the sender's domain.
-          'CXSMTP'    => 'rejected',      # Your email wasn't delivered because Cox was unable to verify that it came from a legitimate email sender.
-          'CXCNCT'    => 'toomanyconn',   # There is a limit to the number of concurrent SMTP connections per IP address
-          'CXMXRT'    => 'toomanyconn',   # The email sender has exceeded the maximum number of sent email allowed.
-          'CDRBL'     => 'blocked',       # The sending IP address has been temporarily blocked by Cox due to exhibiting spam-like behavior.
           'IPBL0001'  => 'blocked',       # The sending IP address is listed in the Spamhaus Zen DNSBL.
           'IPBL0010'  => 'blocked',       # The sending IP is listed in the Return Path DNSBL.
           'IPBL0100'  => 'blocked',       # The sending IP is listed in the Invaluement ivmSIP DNSBL.
@@ -32,70 +70,81 @@
           'IPBL1110'  => 'blocked',       # The sending IP is in the Cloudmark CSI, Return Path and Invaluement ivmSIP DNSBLs.
           'IPBL1111'  => 'blocked',       # The sending IP is in the Cloudmark CSI, Spamhaus Zen, Return Path and Invaluement ivmSIP DNSBLs.
           'IPBL00001' => 'blocked',       # The sending IP address is listed on a Spamhaus blacklist. Check your status at Spamhaus.
+
           'URLBL011'  => 'spamdetected',  # A URL within the body of the message was found on blocklists SURBL and Spamhaus DBL.
           'URLBL101'  => 'spamdetected',  # A URL within the body of the message was found on blocklists SURBL and ivmURI.
           'URLBL110'  => 'spamdetected',  # A URL within the body of the message was found on blocklists Spamhaus DBL and ivmURI.
           'URLBL1001' => 'spamdetected',  # The URL is listed on a Spamhaus blacklist. Check your status at Spamhaus.
         }.freeze
         MessagesOf = {
           'blocked' => [
-            # Cox requires that all connecting email servers contain valid reverse DNS PTR records.
-            'rejected - no rDNS',
-            # An email client has repeatedly sent bad commands or invalid passwords resulting in a three-hour block of the client's IP address.
+            # - An email client has repeatedly sent bad commands or invalid passwords resulting in
+            #   a three-hour block of the client's IP address.
+            # - The sending IP address has exceeded the threshold of invalid recipients and has
+            #   been blocked.
             'cox too many bad commands from',
-            # The reverse DNS check of the sending server IP address has failed.
-            'DNS check failure - try again later',
-            # The sending IP address has exceeded the threshold of invalid recipients and has been blocked.
-            'Too many invalid recipients',
+            'too many invalid recipients',
           ],
-          'notaccept' => [
-            # Our systems are experiencing an issue which is causing a temporary inability to accept new email.
-            'ESMTP server temporarily not available',
+          'requireptr' => [
+            # - The reverse DNS check of the sending server IP address has failed.
+            # - Cox requires that all connecting email servers contain valid reverse DNS PTR records.
+            'dns check failure - try again later',
+            'rejected - no rdns',
           ],
           'policyviolation' => [
-            # The sending server has attempted to communicate too soon within the SMTP transaction
-            'ESMTP no data before greeting',
-            # The message has been rejected because it contains an attachment with one of the following prohibited
-            # file types, which commonly contain viruses: .shb, .shs, .vbe, .vbs, .wsc, .wsf, .wsh, .pif, .msc,
-            # .msi, .msp, .reg, .sct, .bat, .chm, .isp, .cpl, .js, .jse, .scr, .exe.
+            # - The sending server has attempted to communicate too soon within the SMTP transaction
+            # - The message has been rejected because it contains an attachment with one of the
+            #   following prohibited file types, which commonly contain viruses: .shb, .shs, .vbe,
+            #   .vbs, .wsc, .wsf, .wsh, .pif, .msc, .msi, .msp, .reg, .sct, .bat, .chm, .isp, .cpl,
+            #   .js, .jse, .scr, .exe.
+            'esmtp no data before greeting',
             'attachment extension is forbidden',
           ],
           'rejected' => [
             # Cox requires that all sender domains resolve to a valid MX or A-record within DNS.
             'sender rejected',
           ],
+          'systemerror' => [
+            # - Our systems are experiencing an issue which is causing a temporary inability to
+            #   accept new email.
+            'esmtp server temporarily not available',
+          ],
           'toomanyconn' => [
-            # The sending IP address has exceeded the five maximum concurrent connection limit.
+            # - The sending IP address has exceeded the five maximum concurrent connection limit.
+            # - The SMTP connection has exceeded the 100 email message threshold and was disconnected.
+            # - The sending IP address has exceeded one of these rate limits and has been temporarily
+            #   blocked.
             'too many sessions from',
-            # The SMTP connection has exceeded the 100 email message threshold and was disconnected.
             'requested action aborted: try again later',
-            # The sending IP address has exceeded one of these rate limits and has been temporarily blocked.
-            'Message threshold exceeded',
+            'message threshold exceeded',
           ],
           'userunknown' => [
-            'recipient rejected', # The intended recipient is not a valid Cox Email account.
+            # - The intended recipient is not a valid Cox Email account.
+            'recipient rejected',
           ],
         }.freeze
 
         # Detect bounce reason from https://cox.com/
         # @param    [Sisimai::Fact] argvs   Parsed email object
         # @return   [String, Nil]           The bounce reason at Cox
+        # @see      https://www.cox.com/residential/support/email-error-codes.html
         # @since v4.25.8
         def get(argvs)
-          statusmesg = argvs['diagnosticcode']
+          issuedcode = argvs['diagnosticcode']
           codenumber = 0
 
-          if cv = statusmesg.match(/AUP#([0-9A-Z]+)/)
+          if cv = issuedcode.match(/AUP#([0-9A-Z]+)/)
             # Capture the numeric part of the error code
             codenumber = cv[1]
           end
           reasontext = ErrorCodes[codenumber] || ''
 
+          issuedcode = argvs['diagnosticcode'].downcase
           if reasontext.empty?
             # The error code was not found in ErrorCodes
             MessagesOf.each_key do |e|
               # Try to find with each error message defined in MessagesOf
-              next unless MessagesOf[e].any? { |a| statusmesg.include?(a) }
+              next unless MessagesOf[e].any? { |a| issuedcode.include?(a) }
               reasontext = e
               break
             end