Re: How to stop a user from changing the 'From:' header.

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How to stop a user from changing the 'From:' he...
\ rodolfo (20 Sep 2007)
. \ mouss (20 Sep 2007)
. \ Victor Duchovni (20 Sep 2007)
. . \ Jay Chandler (20 Sep 2007)
. . . \ Victor Duchovni (20 Sep 2007)
. . . . \ Jay Chandler (20 Sep 2007)
. . . . . \ Victor Duchovni (20 Sep 2007)
. . . . . . \ Jay Chandler (21 Sep 2007)
. . . . . . . \ Victor Duchovni (21 Sep 2007)
. . \ rodolfo (20 Sep 2007)
. . . \ mouss (21 Sep 2007)

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Subject:	Re: How to stop a user from changing the 'From:' header.
Group:	Postfix-users
From:	mouss
Date:	21 Sep 2007

rodolfo wrote:
> On Thu, 20 Sep 2007, Victor Duchovni wrote:
>> No, Postfix can only constrain the envelope sender to match
>> the authenticated user,
>
>
> Thanks for the answer Victor. Which would be the effect of this
> restriction? (sorry if I sound too newbie)

see

http://www.postfix.org/postconf.5.html#reject_sender_login_mismatch
http://www.postfix.org/postconf.5.html#smtpd_sender_login_maps

this can be used to reject mail if the sender does not match the login,
as specified in smtpd_sender_login_maps.

if you have machines that send system logs (cron, ...) to the postfix
server, make sure to allow them to do so.