NAME
dkimproxy.in - SMTP proxy for verifying DKIM signatures
DESCRIPTION
dkimproxy.in listens on the IP address and TCP port specified by its
first argument (the "listen" port), and sends the traffic it receives
onto the second argument (the "relay" port), with messages getting
verified and having an "Authentication-Results" header added to them.
SYNOPSIS
dkimproxy.in [options] LISTENADDR:PORT RELAYADDR:PORT
smtp options:
--conf_file=FILENAME
--listen=LISTENADDR:PORT
--relay=RELAYADDR:PORT
--reject-error
verification options:
--reject-fail
--hostname=HOSTNAME
daemon options:
--daemonize
--user=USER
--group=GROUP
--pidfile=PIDFILE
--min_servers=NUM
OPTIONS
--daemonize
If specified, the server will run in the background.
--group=GROUP
If specified, the daemonized process will setgid() to the specified
GROUP.
--hostname=HOSTNAME
Overrides the hostname used in the Authentication-Results header. This
header gets added to every verified message. Use this option if the
hostname that appears is not fully qualified or you want to use an
alternate name.
--pidfile=PIDFILE
Creates a PID file (a file containing the PID of the process) for the
daemonized process. This makes it possible to check the status of the
process, and to cleanly shut it down.
--reject-error
This option specifies what to do if an error occurs during verification
of a message. If this option is specified, the message will be rejected
with an SMTP error code. This will result in the MTA sending the
message to try again later, or bounce it back to the sender (depending
on the exact error code used). If this option is not specified, the
message will be passed through with an error listed in the
Authentication-Results header instead of the verification results.
--reject-fail
This option specifies what to do if verification fails and the sender
signing policy says to reject the message. If this option is specified,
the message will be rejected with an SMTP error code. This will result
in the sending MTA to bounce the message back to the sender. If this
option is not specified, the message will pass through as normal.
--user=USER
If specified, the daemonized process will setuid() to USER after
completing any necessary privileged operations, but before accepting
connections.
--min_servers=NUM
Number of process that DKIMproxy shall spawn and get ready for
filtering.
EXAMPLE
For example, if dkimproxy.in is started with:
dkimproxy.in --reject-fail --reject-error 127.0.0.1:10025
127.0.0.1:10026
the proxy will listen on port 10025 and send the verified messages to
some other SMTP service on port 10026.
CONFIGURATION FILE
Parameters can be stored in a separate file instead of specifying them
all on the command line. Use the conf_file option to specify the path
to the configuration file, e.g.
dkimproxy.in --conf_file=/etc/dkimproxy_in.conf
The format of the configuration file is one option per line: name of
the option, space, then the value of the option. E.g.
# this is an example config file
listen 127.0.0.1:10025
relay 127.0.0.1:10026
hostname myhost.example.com
reject_fail
is equivalent to
dkimproxy.out --hostname=myhost.example.com --reject-fail
127.0.0.1:10025 127.0.0.1:10026
SEE ALSO
dkimproxy.out(8), dkim_responder(1), dkimsign(1), dkimverify(1)
dkimproxy.in(8)