s/qmail:

Section: Misc. Reference Manual Pages (qmail-postgrey)
Updated: 8
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NAME

qmail-postgrey - send SMTP connection data to greylisting server

SYNOPSIS

qmail-postgrey ip%netid;port Mail From: Rcpt To: TCPREMOTEIP TCPREMOTEHOST

DESCRIPTION

qmail-postgrey is usually invoked by qmail-smtpd automatically provissioning the SMTP connection information Mail From:, Rcpt To:, TCPREMOTEIP and TCPREMOTEHOST to a greylising server given by IPv4|IPv6%netid;port. port defaults to 60000 and thus can be omitted. IPv6 LLU addresses can be specified adding the netid name following the percentage sign.

GREYLISTING SERVER

Since there is neither a formal API defined for the greylisting lookup nor for the behavior and return codes of the greylisting server, qmail-postgrey only works well with David Schweikert's postgrey implementation.

Here, the server's response upon recognizing the triple CLIENT_IP, (SMTP envelope) SENDER and (SMTP envelope) RECIPIENT is either action=DUNNO, action=PREPEND or action=DEFER_IF_PERMIT and in case of the last, qmail-postgrey returns with 10 telling qmail-smtpd to respond to the client with a SMTP 450 greylisted reply code. Otherwise qmail-postgrey returns 0.

INVOCATION

Unlike for testing reasons, qmail-postgrey is called directly from qmail-smtpd in case the environment variable POSTGREY is defined and provissioned with the greylisting server's IP address (and perhaps netid and port) listening there.

The environment variable POSTGREY is typically defined within sslserver's cdb. Additionally, REPLY_GREYLISTED can be used as environment variable to provide some more descriptive information to the sending MTA which will eventually be visible in a bounce message.

CREDITS

qmail-postgrey and its integration into qmail-smtpd is based on Jan Mojzis implementation and used by permission.

This document was created by man2html, using the manual pages.
Time: 12:19:24 GMT, December 09, 2024