How to Remove X-headers

Alex Broens ms-list at alexb.ch
Thu Mar 12 08:47:28 GMT 2009


On 3/12/2009 9:35 AM, Glenn Steen wrote:
> 2009/3/11 Alex Broens <ms-list at alexb.ch>:
>> On 3/11/2009 10:50 PM, Glenn wrote:
>>> We use MailScanner and Postfix on a mail gateway server and forward mail
>>> to an internal Microsoft Exchange 2003 server.  Evidently, enough X-headers
>>> have accumulated in an Exchange database to cause a problem, so we need to
>>> remove X-headers before they are forwarded to the Exchange server.
>>>
>>> There is a line in MailScanner.conf that allows us to name whatever
>>> headers we want to remove ("Remove These Headers"), but this raises some
>>> questions.  If we just blanket remove all X-headers, won't this defeat
>>> features of MailScanner that depend on MailScanner adding headers?
>>>
>>> According to hints in the MailScanner rules directory, we should be able
>>> to use regular Perl expresssions to create a ruleset to exclude certain
>>> headers from the delete list.  My problem is that I don't have a clue how to
>>> write regular Perl expressions.  From what I've read online, for example,
>>> the lines below should be equivalent, but when I use the Perl expression in
>>> the ruleset it doesn't work.
>>>
>>> From:  [ipaddress]  X-MimeOLE:    ##this removes the X-MimeOLE header
>>>
>>> From:  [ipaddress]  /^XMime.*\:/  ##this doesn't
>>>
>>> I know this isn't a Perl forum, but I'm hoping that someone who has tried
>>> this can enlighten me.  If I could just get a simple expression to work, I
>>> might be able to build what I need.  Thanks.   -Glenn.
>> Before you start breaking MIME headers, who told you this or what MS KB
>> article covers this?
>>
> Apart from that... this would be the job of PF, IMO... Just a header
> check with an IGNORE... Something like:
> /^X-MimeOLE:/                                  IGNORE  # This drops
> the MIME type header
> .... would work nicely.

*normally* PF header checks happen before MS/SA see the msgs
removing some of these headers would do fun stuff with SA's rules.
OL would become the worst ratware  :-)
(rants left out on purpose :-)

Whatever, the reason you were given to do this feels like very bad advice.

> But do as Kai tells you, think carefully on what the ramifications of
> any such exclusion would be before implementing!
> There are quite a few examples of headers to remove on various
> postfix-related sites... Google and take your pick:-)
> 
> Cheers


More information about the MailScanner mailing list