Provided by: opensmtpd-extras_5.7.1-1build1_i386 bug

NAME

     filter-pause — smtpd filter to pause on new connections

SYNOPSIS

     filter-pause [-s seconds]

DESCRIPTION

     filter-pause is a filter for smtpd(8) which can be used to pause on new
     connections before emitting the standard initial SMTP greeting.  This is
     useful to avoid the so called “slamming” technique used by some senders
     of spam mails.

     The options are as follows:

     -s seconds  Set the number of seconds to pause before sending the initial
                 greeting.  The accepted values are withing the range of 1s
                 and 300s.

                 The default seconds value is 5s.

     With filter-pause enabled, smtpd simply waits the specified amount of
     seconds on each new connection.  If the remote server starts sending SMTP
     commands before the greeting, the connection is rejected.  Otherwise, the
     connection is accepted and normally processed.

SEE ALSO

     filter_api(3), smtpd.conf(5), smtpd(8)

STANDARDS

     J. Klensin, Simple Mail Transfer Protocol, RFC 5321, October 2008.

HISTORY

     The first version of filter-pause was written in 2015.

AUTHORS

     Joerg Jung ⟨jung@openbsd.org