Policyd is an anti-spam plugin for Postfix that does greylisting, sender (envelope, SASL, or host/IP)-based throttling (on messages and/or volume per defined time unit), spam trap monitoring/blacklisting, HELO auto-blacklisting, and HELO randomization prevention (HRP).
License: GNU General Public License (GPL)
Changes:
This release adds greylisting support and auto-whitelisting. It adds auto-blacklisting based on count or count and percentage of auth vs. nonauth triplets. Bugs with the amavisd-new plugin have been fixed. SASL support has been added to policies.
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