[Mailman-Users] unparseable message

[Mark Sapiro]

Barry Finkel wrote:
>
>     The directory /var/lib/mailman/qfiles contains files.
>     It needs to be empty for the upgrade work properly.
>
>I looked at that directory, and I found a number of
>
>     bounces/xxxxx.bak

<snip>

>I looked at the logs and found an unparseable rejection message.
>I am including it below.  I am not sure what the problem is, but I
>believe that the 
>
>     content-type: message/rfc822
>
>attachment contains the beginning of the original MIME-encoded
>posting, and Mailman is getting confused with this MIME-within-MIME.
>Here is a message from the Mailman error log:
>
>     Uncaught runner exception: No terminating boundary and no trailing
>     empty line

<snip>
>
>------_=_NextPart_001_01C8A3A7.4B24E858--
>--orAt.4Is3ZceEe.1I4wvb.Aylgfr0--


Mailman (actually the Python email package) doesn,t like the fact that
there is no intervening empty line between the terminating boundary of
the message/rfc822 part and the terminating boundary of the outer
message.

Quoting from section 5.1.1 of RFC 2045

  The boundary may be followed by zero or more characters of linear
  whitespace. It is then terminated by either another CRLF and the
  header fields for the next part, or by two CRLFs, in which case
  there are no header fields for the next part.

The real issue here is that the bounce message was attempted to be
processed and logged as unparseable when it was received on 21 April,
but due to an error in 2.1.9, the .bak file for the unparseable
message wasn't removed.

The current Python email package is more forgiving and in fact does
parse this message, but because of incompatibilities with older Python
versions which are still supported by Mailman, we ship our Mailman
package with an older email package.

The sending MTA has sent a DSN which is not RFC 2045 compliant in that
the terminating boundary of the embedded message/rfc822 part is not
followed by two CRLFs. We should be more forgiving, and the current
email package is, but the initial fault is with the MTA that created a
non-compliant message.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan