Rewrite or delete headers

[Rouslan]

Hi folks,

Is there any way to remove or hide internal IP/Hostname in headers?

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Regards,
Rouslan

[Claus Aßmann]

Rouslan wrote:

> Is there any way to remove or hide internal IP/Hostname in headers?

Why?

PS: yes.
--
Note: please read the netiquette before posting. I will almost never
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[Lars Kellogg-Stedman]

>> Is there any way to remove or hide internal IP/Hostname in headers?
>
> Why?

Because one often wants to obscure the details of one's internal mail
environment, or prevent local smtp filters (e.g., those used for mail
filtering/virus scanning/etc) from resulting in a large number of
meaningless "Received:" headers, etc.

-- Lars

--
Lars Kellogg-Stedman <jn8g543...@jetable.net>
This email address will expire on 2005-11-21.

[Rouslan]

Exactly.

[Lars Kellogg-Stedman]

> Is there any way to remove or hide internal IP/Hostname in headers?

If you're just trying to remove the Received: headers, you could
configure your internal systems to not add the Received: header in the
first place.

You could probably write a custom filter to strip or obscure the
headers. This would probably be the most flexible solution. There are
milter bindings for Perl, Java, etc., so writing one shouldn't be too
bad.

-- Lars

--
Lars Kellogg-Stedman <1o4ibj7...@jetable.org>
This email address will expire on 2005-11-22.

[Rouslan]

Lars,

First off all thank you for your replies.

Lars Kellogg-Stedman wrote:
> If you're just trying to remove the Received: headers, you could
> configure your internal systems to not add the Received: header in the
> first place.

What do you mean? In my example headers: I sent e-mail from
my workstation in internal network. E-mail gateway runs sendmail 8.13.15
and
split DNS (bind with external/internal view statements). I think about
solution without milter usage, only via sendmail configuration.

> You could probably write a custom filter to strip or obscure the
> headers. This would probably be the most flexible solution. There are
> milter bindings for Perl, Java, etc., so writing one shouldn't be too
> bad.

Yes, I installed mimedefang, but I really have no time to configure it
now. If you know other milters that I may use, please write me.

Regards,
Rouslan

[Lars Kellogg-Stedman]

>> If you're just trying to remove the Received: headers, you could
>> configure your internal systems to not add the Received: header in the
>> first place.
>
> What do you mean?

I mean that you can configure Sendmail to not add the Received: header
when email passes through the system. See, for example:

http://lookleap.com/groups.google.com/a3

You can also configure Sendmail to pass your outgoing messages through
procmail, and use that to filter out headers:

http://lookleap.com/groups.google.com/a4

And you can also modify the sendmail source to do the same thing;
instructions for this are apparently in the O'Reilly sendmail book.

[Rouslan]

Excellent!

I replaced in sendmail.cf:
HReceived: $?sfrom $s $.$?_($?s$|from $.$_)

by:
HReceived: $?sfrom rshell.net (mail.rshell.net [192.115.133.35])

One note: this adds surplus header into received message, but is is not
critical. Thank you for an advice.

Regards,
Rouslan