肖建彬的博客

作者: 肖建彬 | 可以转载, 转载时务必以超链接形式标明文章原始出处和作者信息及版权声明
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Wietse Venema wrote to postfix-users@postfix.org:

What are Milters?
-----------------

Milters (mail input filters), introduced with Sendmail 8.10, look
at both SMTP commands and at message content.

Milters are applications that run outside of the MTA, and can can
instruct the MTA to {accept / reject / discard } {a connection /
command / message content}, to {delete / add} a {recipient / header},
and to replace a {header / entire message body}.

The purpose of adding this to Postfix is to enable the already
existing applications for Sendmail 8 to sign mail or to verify mail
authenticity (SenderID or DKIM) as well as already existing
applications for email content management.

Postfix status update.
----------------------

The first portion of Postfix Milter support for accept / reject /
discard is now 99% done, and I'm starting on the much smaller
portion that modifies message content.

For Postfix 2.3, the plan is to implement a large enough subset so
that the SenderID and DKIM plug-ins work, and to add the rest soon
after the 2.3 release.

Support for SenderID/DKIM plug-in is a requirement before Postfix
2.3 can be released.

The Postfix Milter implementation is pluggable; support for Sendmail
X filters can be added later (it's different), without having to
rip up existing code.

       Wietse

Postfix将要支持微软的senderid,和yahoo的domainkeys：）