MDN Construction from AS2/AS3 Message

When an AS2 or AS3 message requests for an MDN, it must have the following:

• AS2-To/AS2-From (or AS3-To/AS3-From)
• Disposition-Notification-To
• Message-ID

FREDI builds the MDN based on the field values of headers in the subject message, and errors discovered in it:

• Message Headers.  The following headers are created when an MDN is built.
  • MIME-Version. The default value is set to "1.0".
  • Date.  The default value is set to the current date.
  • Content-Type.  The default value is set to "multipart/report; report-type=disposition-notification; boundary="default.boundary.mdn".  However, the boundary of the MDN is whatever has been set on the subject message of the mailDocument object and concatenated with the string ".mdn".  That is, if the boundary was set to  "fredi.boundary", then the MDN boundary is "fredi.boundary.mdn".
  • AS2-From (or AS3-From).  The value set here is taken from the subject message header AS2-To (or AS3-To).
  • AS2-To (or AS3-To).  The value set here is taken from the subject message header AS2-From (or AS3-From) field
    
• 1st Body Part.  The first body part is created as follows:
  • No field header is created.
  • The human readable text depends on the existence of the following headers on the subject message:
    • Subject.  The value of this header is enclosed in quotes when inserted into the readable text.
    • AS2-To (or AS3-To).
    • Message-ID.
    • Date.  The value of the date header follow the Date syntax.  If the syntax is not valid then the current date is used.

    The values of these fields are inserted into the text as follows:
    

    The message [ with message ID <Message-ID>] [ sent on <Date>] [ to <AS2-To/AS3-To>] [ with subject <Subject>] has been processed.  This does not guarantee that the message has been read or understood.

    A bracketed phrase indicates that the phrase occurs only if the value of that field exists. For example, if the headers have the following values:
    • SUBJECT = "Syntax of MDN"
    • AS2-TO (or AS3-TO) = "James"
    • MESSAGE-ID = "123@global.com"
    • DATE = <Empty>

    The text would read:

    The message with message ID 123@global.com to James with subject "Syntax of MDN" has been processed.  This does not guarantee that the message has been read or understood.

     

• 2nd Body Part.  The second body part is created as a composite message and constructed as follows:
  • The Content-Type header is created and its value is set to "message/disposition-notification".
  • A body part is created in this body part and is constructed as follows:
    • Reporting-UA.  This header is created if the value assigned to the property Property_Reporting_UA in mailDocument exists.  The value of this header is set to the property value.
    • Original-Recipient.  This header is created if the subject message also has an Original-Recipient header with a value.  The value of this header is formed with the string "rfc822;" attached to the beginning of the value. For example, "rfc822; John <JSmith@somesite.com>" where "John <JSmith@somesite.com>" is the Original-Recipient of the subject message.  If a corresponding Original-Recipient header is not in the subject message or no value is present, then this header is omitted in the MDN.
    • Final-Recipient.  The value from the AS2-To field of the subject message is assigned to this header.  It is formed with the string "rfc822;" attached to the beginning of the value. For example, "rfc822; John" where "John" is the value taken from the AS2-To field.  If the header does not exist or contains no value, the  header is still created with an empty value.  However, if there is a value formed for this field, the value is also copied to the Original-Recipient header of the MDN -- any existing value previously determined is overwritten.
    • Original-Message-ID.  The value of this field is taken from the Message-ID field of the subject message.
    • Disposition.  The value of this header depends on how the MDN request was activated:
      • If the request was made through the required fields in the subject message (Disposition-Notification-To, Return-Path, Message-ID), then the field value is "automatic-action/MDN-sent-automatically;processed".
      • If the request was made by setting the EnableAcknowledgment to TRUE then the field value is set to "manual-action/MDN-sent-manually;processed".

      Furthermore, if there were errors detected in the subject message, a modifier is appended to the disposition value:

      • "Warning" if a warning was generated.
      • "Error" if a severe error was generated.

      The list of warnings or errors are then listed with Warning and Error headers. For example,
      

      Disposition: automatic-action/MDN-sent-automatically;processed/warning
      Warning: [DESCRIPTION:Internet message header 'Date' has invalid syntax value.][CODE:13921]
      Warning: [DESCRIPTION:Month value expected. 'Header:'Date''][CODE:13714]
      

    • Received-Content-MIC.  The MIC calculated is for the body of the subject message, and the resulting value is assigned to this header.  The subject message must have the following header and value for this header to be added to the MDN.
      • Disposition-Notification-Options.  The value of this header must be "signed-receipt-protocol=optional,pkcs7-signature; signed-receipt-micalg=optional,sha1".

      To prevent MIC calculation and omit this header, disable the option MailDocOpt_EnableMDN in the mailDocument object.  The Disposition-Notification-Options not only calculates the MIC but will digitally sign the MDN, requiring that a private key be specified to process the MDN.
      

• 3rd Body Part is not created.