NAME

       opendmarc - DMARC email policy filter for MTAs

SYNOPSIS

       opendmarc  [-A]  [-c  configfile]  [-f] [-l] [-n] [-p socketspec] [-P pidfile] [-t file[,file[...]]]  [-u
       userid[:group]] [-v] [-V]

DESCRIPTION

       opendmarc implements the proposed DMARC specification for authentication  of  message  and  reporting  of
       observed traffic.

       opendmarc  uses  the  milter interface, originally distributed as part of version 8.11 of sendmail(8), to
       provide a DMARC processing service for mail transiting a milter-aware MTA.

       Most, if not all, of the command line options listed below can also be set using  a  configuration  file.
       See the -c option for details.

       opendmarc  relies  on  addition  of  Authentication-Results fields by upsteam filters on trusted hosts to
       collect input to the DMARC algorithm.  It does not itself do DKIM or SPF evaluation.

OPTIONS

       -A     Automatically re-start on failures.  Use with caution; if the  filter  fails  instantly  after  it
              starts,  this  can  cause  a  tight  fork(2) loop.  This can be mitigated using some values in the
              configuration file to limit restarting.  See opendmarc.conf(5).

       -c configfile
              Read the named configuration file.  See the opendmarc.conf(5) man page for details.  Values in the
              configuration  file are overridden when their equivalents are provided on the command line until a
              configuration reload occurs.  The OPERATION section describes  how  reloads  are  triggered.   The
              default  is  to  read a configuration file from /etc/opendmarc.conf if one exists, or otherwise to
              apply defaults to all values.

       -f     Normally opendmarc forks and exits immediately, leaving the service  running  in  the  background.
              This flag suppresses that behaviour so that it runs in the foreground.

       -l     Log via calls to syslog(3) any interesting activity.

       -n     Parse  the  configuration  file  and  command line arguments, reporting any errors found, and then
              exit.  The exit value will be 0 if the filter  would  start  up  without  complaint,  or  non-zero
              otherwise.

       -p socketspec
              Specifies  the  socket  that  should  be  established  by  the  filter to receive connections from
              sendmail(8) in order to provide service.  socketspec is in one  of  two  forms:  local:path  which
              creates a UNIX domain socket at the specified path, or inet:port[@host] or inet6:port[@host] which
              creates a TCP socket on the specified port within the specified protocol family.  If the  host  is
              not  given  as either a hostname or an IP address, the socket will be listening on all interfaces.
              If neither socket type is specified, local is assumed, meaning the parameter is interpreted  as  a
              path  at  which  the  socket  should be created.  If an IP address is used, it must be enclosed in
              square brackets.  This parameter is mandatory.

       -P pidfile
              Specifies a file into which the filter should write its process ID at startup.

       -t file[,file[,...]]
              Reads email messages from the named files and processes them as  if  they  were  received  by  the
              filter.   The  service  is  not started, and actions normally sent back to the MTA will instead be
              printed on standard output.

       -u userid[:group]
              Attempts to be come the specified userid before starting operations.  The process will be assigned
              all of the groups and primary group ID of the named userid unless an alternate group is specified.
              See the FILE PERMISSIONS section for more information.

       -v     Increase verbose output during test mode (see -t above).  May  be  specified  more  than  once  to
              request increasing amounts of output.

       -V     Print  the  version  number and supported canonicalization and signature algorithms, and then exit
              without doing anything else.

SIGNALS

       Upon receiving SIGUSR1, if the filter was started with a configuration file, it will be re-read  and  the
       new values used.  Note that any command line overrides provided at startup time will be lost when this is
       done.  Also, the following configuration file values (and their corresponding command line items, if any)
       are  not  reloaded through this process: AutoRestart (-A), AutoRestartCount, AutoRestartRate, Background,
       MilterDebug, PidFile (-P), Socket (-p), UMask, UserID (-u).  The filter does not automatically check  the
       configuration file for changes and reload.

VERSION

       This man page covers version 1.3.2 of opendmarc.

COPYRIGHT

       Copyright (c) 2012, The Trusted Domain Project.  All rights reserved.

SEE ALSO

       opendmarc.conf(5), sendmail(8)

       Sendmail Operations Guide

       RFC4408 - Sender Policy Framework

       RFC5321 - Simple Mail Transfer Protocol

       RFC5322 - Internet Messages

       RFC5451 - Message Header Field for Indicating Message Authentication Status

       RFC6376 - DomainKeys Identified Mail

       RFC6591 - Authentication Failure Reporting Using the Abuse Reporting Format

                                           The Trusted Domain Project                               opendmarc(8)