filter-senderscore8

Usage

Overview

The filter-senderscore filter for the OpenSMTPD (smtpd(8)) server filters sessions based on their SenderScores reputation score. Its options are:

-blockBelow score

Displays an error banner for sessions with a reputation score below score and then disconnects.

-blockPhase phase

Determines at which phase -blockBelow is triggered. The default is connect. Valid choices are connect, helo, ehlo, starttls, auth, mail-from, rcpt-to, and quit. Note that quit will result in a message at the end of a session and may only be used to warn the sender that its reputation is degrading, as it will not prevent transactions from succeeding.

-junkBelow score

Prepends a ‘X-Spam: yes’ header to messages for sessions with a reputation score below score.

-slowFactor factor

Delays all answers by this many milliseconds, where ‘score’ is the reputation score:

factor − ((factor ÷ 100) ∗ score)

-scoreHeader

Adds an ‘X-SenderScore’ header with the sender's reputation score if known.

Exit status

The filter-senderscore utility exits 0 on success, and >0 if an error occurs.

Examples

Adding the following to smtpd.conf enables filter-senderscore for all incoming connections.

filter "senderscore" proc-exec \
       "/usr/local/bin/filter-senderscore -blockBelow 50 \
                                          -junkBelow  80 \
                                          -slowFactor 1000"
listen on all filter "senderscore"