[Mailman-Users] Newbie Question -- Attachments (again)

[Mark Sapiro]

Newman, Linda (newmanld) wrote:

>I have read through the FAQ and tried to locate every piece of information I
>could about MIME types and attachments, esp. reading 4.39, and I'm still
>confused, so am hoping that others can provide some simple clarification.
>
>What I'd like to do:
>   1) Prevent all attachments from going through.  (Note that if my settings
>below are too broad and will result in rejecting messages that aren't really
>attachments, let me know.)

See below.

>   2) Accept html, or real text format formatted messages without
>translating them to plain text.  However, if this means that other formats
>such as pdf, word, etc., would also have to be accepted, than I'd give up on
>html.

It doesn't, you can do it - except see below regarding
multipart/alternative.

>   3) Send a notice automatically to a sender if their attachment has been
>rejected.

I don't think you can do this if the whole message is not rejected.

>   4) Send the remaining plain text part of the message to the list without
>the attachment.

You can do this, but I don't think you can get a reject notice to the
poster in this case.

>My current 'Content Filtering' options (see below) are rejecting attachments
>and html-formatted messages.   The entire message is rejected -- even if
>there are remaining plain text parts.  RTF formatted messages are, however,
>converted to plain text.  No notice of a rejection is sent to the poster, so
>I've configured the last option to send the message to the e-list owner, so
>that the owner could manually notify users.

This will only work if the entire message is filtered and nothing is
left for the list.

>Note that I don't seem to have access to the unix shell.
>
>My current list Content Filtering options are as follows:
>
>Should Mailman filter the content of list traffic according to the settings
>below?   -- Yes

Right.

>Remove message attachments that have a matching content type.  <none listed>
>Remove message attachments that don't have a matching content type.  -- I've
>listed two types -- text/plain  <and, on a separate line> text/html

This won't work. It's too restrictive it will only allow single part
messages whose content-type is text/html or text/plain. You also need
to allow the text/plain and/or text/html parts from multipart
messages. Thus you must add to the above types

multipart/mixed
multipart/alternative

Also, you may wish to add

message/rfc822

to allow text/plain and text/html parts from some forwarded messages.

Note that allowing these types does not allow the entire multipart
through, it just alows its sub-parts to be examined rather than
deleted.

Further, note that if the message contains a multipart/alternative part
with both a text/plain alternative and a text/html alternative, only
the first alternative which is always supposed to be the text/plain
part.

To get HTML through to the list you either have to disallow text/plain
or make sure the HTML is not in a multipart/alternative part with a
text/plain alternative. This is difficult if not impossible to do with
some MUAs.

>Should Mailman convert text/html parts to plain text?	No

Good.

>Action to take when a message matches the content filtering rules.   Forward
>to List Owner

See above.

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